Ebook Diagnostic pediatric ultrasound: Part 2

(BQ) Part 2 book Diagnostic pediatric ultrasound presents the following contents: Spleen, pediatric intestinal ultrasonography, pancreas, kidneys, adrenal glands, sonography of the female genital tract, male genital tract, musculoskeletal ultrasound, ultrasound guided inter ventional procedures - biopsy and drainage

| 11.05.15 - 18:17

10 Spleen

Samuel Stafrace

The spleen is a pyramid-shaped organ normally located in the

left upper quadrant It forms part of and is the largest organ

within the lymphoproliferative system It plays a major role in

the immune system and also functions as a filter of damaged

and abnormal red blood cells

Imaging of the spleen starts and often rests very much with

ultrasound Depending on a child’s age, this organ can be

imaged with transducers of different frequencies Exquisite

images can be obtained with higher frequency, particularly in

the younger child

Requests for examining this organ are often related to a

clini-cally palpable increase in its size Other frequent indications are

for the assessment of hematologic conditions and in the setting

of trauma The assessment and measurement of the spleen are

part of the normal ultrasound examination of the pediatric

abdomen

This chapter describes the normal appearances, variants,

and most common pathologies of the spleen as seen with

ultrasound

10.1 Normal Anatomy and

Variants

10.1.1 Embryology

The spleen begins to develop at the fifth week of fetal life It

develops from multiple cellular nests located within the dorsal

mesogastrium (▶Fig 10.1) Symmetrical splenic precursors are

thought to exist with preferential development of the left sided

splenic tissue These cellular nests eventually fuse to form a

sin-gle organ The small anterior notch often seen in the anterior

aspect of the spleen is thought to result from this fusion

pro-cess The presence of accessory small spleens (splenunculi),

seen in about 10% of normal individuals, results from

incomplete fusion of all the splenic tissue into one organ

Given its embryonal development in the dorsal trium, the final location of splenic tissue is very much depen-dent on normal situs and normal bowel rotation At 8 weeks’gestation, the liver rotates to the right, and the stomach andspleen rotate to the left The peritoneal reflections betweenthese organs follow their rotational movement

mesogas-10.1.2 Anatomical Considerations

The final anatomical splenic position and the layout of its ciated peritoneal reflections are demonstrated in ▶Fig 10.2.The spleen is surrounded by peritoneum, with folds that meet

asso-in positions anterior and posterior to the organ The splenic ligament connects the spleen with the greater curvature

gastro-of the stomach anteriorly The lienorenal ligament in turn nects the spleen to the retroperitoneum posteriorly The tail ofthe pancreas is partly located within this latter peritonealreflection and can be easily seen in close relation to the splenichilum on ultrasound The splenic hilum effectively points medi-ally between the stomach and the left kidney, both of whichleave an indentation Medial to the gastrosplenic and lienorenalligaments is the lateral aspect of the lesser sac of the peritonealcavity Further peritoneal reflections run from the spleen supe-riorly to the diaphragm (phrenicosplenic ligament) and inferi-orly to the colon (splenocolic ligament)

con-Superiorly, the spleen is related to the diaphragm, lying in aconcavity within the left hemidiaphragm Anteriorly, the organ

is related to the stomach and left colon Posteriorly lie the phragm, left pleura, lung base, and chest wall

dia-Arterial blood supply comes through the splenic artery,which is a branch of the celiac trunk of the aorta This coursesbehind the pancreas and reaches the spleen through the lie-norenal ligament The splenic artery divides into a number ofbranches before entering the spleen This is described to followtwo main patterns In the distributed type (70%), the primarytrunk is short and many long branches reach the splenic hilum

Liver

Stomach

Spleen

Fig 10.1 Developmental status of the spleen within the dorsal

mesogastrium at 5 weeks’ gestational age

LKLRLS

GH

GSFL

Spleen

Fig 10.2 Anatomical drawing demonstrating the final position of thespleen with the associated peritoneal reflections AO, aorta; IVC, inferiorvena cava; FL, falciform ligament; GH, gastrohepatic ligament; GS,gastrosplenic ligament; LR, lienorenal ligament; LS, lesser sac; LK, leftkidney; RK, right kidney

Alternatively, in the magistral type (30%), the main trunk is long

with short arterial branches at the hilum The splenic vein

forms in the lienorenal ligament from venous tributaries, which

leave the spleen at the hilum The unified vein travels with the

artery behind the pancreas to join with the superior mesenteric

vein and form the portal vein

Histologically, the spleen is formed by a fibrous capsule that

supplies a network of trabeculations serving as a supportive

framework for the functional tissue The functional tissue

con-sists of two types The white pulp (which derives its name from

its appearance on gross pathology specimens) consists of

groups of lymphocytes and lymphoid follicles The red pulp

comprises the remainder of the spleen (approximately 75% of

the volume) and is composed of venous sinusoids through

which the blood slowly filters

10.1.3 Technique and Normal

Ultrasound Appearances

On interrogation with ultrasound, the normally located spleen

is identified in the left upper quadrant, above the left kidney

and under the left hemidiaphragm, either through a window

under the left lower rib margin or through the lower intercostal

spaces Images should be obtained in the transverse and coronal

oblique planes along the length of the organ (▶Fig 10.3 and

▶Fig 10.4) These images can generally be obtained in the

supine position, although rotating the child into the lateral

decubitus position (▶Fig 10.5) can assist in obtaining a suitable

window when imaging in the supine position is proving di

ffi-cult Occasionally, the lung and pleura can partially obscure the

down the lower left intercostal spaces until the organ comesinto view (▶Fig 10.6; Video 10.6)

10.1.4 Echogenicity and Changes in Echogenicity with Age

As a rule of thumb, the spleen is expected to have echogenicitysimilar to that of the liver and appear more echogenic than theadjacent kidney This is assuming that the hepatic and renalechogenicity is normal when these organs are used as a com-parison for assessing the echogenic appearance of the spleen

The spleen appears diffusely homogeneous When it is uated with higher-frequency probes, the echotexture canappear rather heterogeneous, and this finding should not bemisinterpreted as pathology (▶Fig 10.7) The degree of hetero-geneity ranges from mild granularity to better-defined tinyareas of hypoechogenicity throughout the organ Some authorshave clearly demonstrated that these heterogeneous appearan-ces change with age and are best identified in children betweenthe ages of 1 and 5 years Such appearances are attributed tothe presence of white pulp/lymphoid follicles in the spleen,which are thought to account for the tiny focal areas of lowechogenicity described

eval-The inability to demonstrate such heterogeneity in infants isthought to result from the immaturity of the organ at this ten-der age Difficulty in seeing such detail in older children mayresult from their increased size, reducing the resolutionobtained, although the literature indicates that the chances ofdemonstrating such heterogeneity increases both with age andwith organ size

Fig 10.3a,b Normal transverse ultrasound images of the spleen a Position of the probe in the left lateral aspect b Corresponding ultrasound image.The stomach (St) can be seen anterior to the spleen

| 11.05.15 - 18:17

Fig 10.4a–c Normal coronal oblique ultrasound images of the spleen a Position of the ultrasound probe b Corresponding ultrasound image

c The left kidney (LK) anterior to the spleen is visualized in the more coronal posterior plane

Fig 10.5 The lateral decubitus position can be helpful when images of

the spleen are obtained, particularly in the coronal/coronal oblique

Spleen

10.1.5 Vascularity

When interrogated with color Doppler ultrasound, the spleen

appears hyperemic The splenic artery is seen to arise from the

celiac trunk and can be followed along its course behind the

pancreas into the lienorenal ligament and splenic hilum, where

its branches can be identified (▶Fig 10.8) Similarly, the

drain-ing venous tributaries are seen in the splenic hilum formdrain-ing the

splenic vein This can be followed behind the pancreas close to

the artery to its junction with the superior mesenteric vein

(▶Fig 10.9)

10.1.6 Normal Variants

Splenunculi

In around 10% of healthy individuals, failure of all the

embry-onic splenic tissue to join and form a single spleen may result in

the presence of a small round or oval area of normal splenic

tis-sue adjacent to the main splenic organ, known as an accessory

spleen or splenunculus If multiple areas are present, these

are referred to as splenunculi (▶Fig 10.10) These are often

identified incidentally on scanning Their echogenicity is similar

to that of the main spleen Splenunculi derive their blood ply from branches of the splenic artery

sup-Splenunculi are common and often of no clinical significance.They rarely can present with torsion and infarction(▶Fig 10.11) They can also significantly enlarge and becomehypertrophic, assuming the function of the larger spleen, inhematopoietic conditions after a splenectomy, resulting inrecurrent hypersplenism

Splenic Notch

A small notch/cleft can occasionally be identified on the medialaspect of the undersurface of the spleen (▶Fig 10.12) This isthought to be a remnant from the fusion of the splenic nests oftissue during embryonal development This is easier to appreci-ate in cross-sectional imaging than with ultrasound In thecontext of trauma, the notch can be mistaken for a peripherallaceration However, one would expect some free fluid/hemo-peritoneum adjacent to such a finding in the case of an acutetraumatic laceration

Fig 10.6 Coronal oblique ultrasound image demonstrating artifact

from the lung (white arrows), which obscures visualization of the spleen

(black arrow)

Fig 10.7 Coronal oblique image of the spleen obtained with a frequency (12 MHz) planar probe in a 4-year-old child The subtle,diffuse, heterogeneous appearances throughout the organ should not

high-be misinterpreted as pathology

| 11.05.15 - 18:17

Fig 10.8a–c Normal appearances of the splenic arterial blood supply a Transverse midline ultrasound image of the retroperitoneum b Same imageplane with color Doppler In both images (a and b) the splenic artery can be seen originating from the celiac trunk and coursing behind the pancreastoward the left (arrows) c Coronal oblique image at the splenic hilum with color Doppler showing the distal splenic artery (arrows) and its brancheswithin the spleen (arrowheads)

Spleen

Fig 10.9a–c Normal appearances of the splenic venous drainage a Transverse midline ultrasound image of the retroperitoneum b Same image planewith color Doppler In both images (a and b) the distal splenic vein (white arrows) can be seen behind the body of the pancreas, forming the portal vein(black arrow) after it joins with the superior mesenteric vein (out of plane) behind the neck of the pancreas c Coronal oblique image at the splenichilum with color Doppler showing the venous tributaries in the hilum (arrows) These join to form one splenic vein.

| 11.05.15 - 18:17

Fig 10.10a,b Curvilinear (a) and planar high-frequency (b) coronal

oblique ultrasound images from a normal 10-year-old boy

demon-strating an accessory spleen at the splenic hilum (arrows) Note that

the echogenicity and texture of the splenunculus and the larger spleen

are similar with both probes

Fig 10.11a,b Fifteen-year-old boy presenting with acute abdominalpain and fever a Transverse ultrasound image demonstrates an ovalhypoechoic mass in the left upper quadrant (arrows) b Axial computedtomography after contrast shows that the nonenhancing mass (whitearrows) lies anterior to the normal spleen (black arrow) This massrepresented an infarcted torted splenunculus

Spleen

10.1.7 Normal Splenic Size

The spleen grows with the growing child Normal data areavailable for splenic length in premature infants, neonates, andolder children (▶Table 10.1 and ▶Table 10.2) ▶Fig 10.13demonstrates the appropriate method of measuring the spleen

in the coronal plane At birth, the spleen measures between 2.5and 4.9 cm in length At full growth, the spleen is expected tomeasure between 8.7 and 11.0 cm in a girl and 9.5 and 12.5 cm

in a boy

Tips from the Pro

●The spleen should be assessed systematically in two planes

Always measure and document the craniocaudal length ofthe spleen Do get into the habit of assessing the splenicechotexture with a higher-frequency probe Although thismay not allow the full depth of the spleen to be assessed, itprovides great views of the echotexture and makes it possi-ble to detect subtle lesions that, when small and diffuse, maynot be seen with standard probes and settings Do not mis-take the normal heterogeneity seen with higher-frequencyprobes for pathology

Fig 10.13 Coronal oblique ultrasound image in a normal 10-year-oldchild demonstrating the appropriate method for measuring the length

of the spleen

Fig 10.12 Axial computed tomographic scan demonstrating a splenic

cleft/notch (arrow), which should not be misinterpreted as pathology

Table 10.1 Splenic length in premature infants and neonates

Splenic length (cm)Gestational age

(weeks)

No of patients Mean length

(± 1 SD)

Minimum–maximum

24–31 29 2.4 (0.4) 1.6–3.2

32–35 34 2.8 (0.5) 1.7–4.0

36–37 35 3.3 (0.4) 2.6–4.2

38–41 155 3.4 (0.5) 2.4–4.9

Abbreviation: SD, standard deviation Source: Reprinted with permission

of Elsevier from Soyupak SK, Narli N, Yapicioglu H, Satar M, Aksungur

EH Sonographic measurements of the liver, spleen and kidney

dimensions in the healthy term and preterm newborns Eur J Radiol

2002;43(1):73–78 Note: This study was performed in 261 healthy

newborn infants Craniocaudal dimensions of the spleen were

deter-mined with ultrasonography

The splenic peritoneal ligaments, which are pivotal in

support-ing the spleen, may be elongated, allowsupport-ing the spleen to be

dis-placed inferiorly from its expected location, even down to the

pelvis An abnormally located spleen can be detected

inciden-tally during a routine ultrasound examination or palpated

clini-cally and may be suspected to represent an abdominal mass

A wandering spleen may present with abdominal pain in either

of two different clinical scenarios: recurrent abdominal pain

from intermittent torsion or severe acute pain from torsion,

secondary ischemia and infarction of part or all of the spleen

In the scenario of torsion, an ultrasound examination shows

the spleen to be absent from its normal location in the left

upper quadrant Once identified, the spleen is found to be

enlarged, with a heterogeneous appearance Focal infarctions

appear as areas of lower echogenicity with absence of flow on

interrogation with color Doppler A whirlpool appearance of the

vascular blood supply at the hilum and secondary ascites can be

seen (▶Fig 10.14)

Splenic Fusion Abnormalities

Splenogonadal fusion is a rare developmental anomaly in which

aberrant splenic tissue is fused to ovarian or testicular tissue

Congenital fusion of splenic tissue with the kidneys nal fusion) has also been rarely described

(splenore-Splenosis

After traumatic rupture of the spleen or occasionally after gical splenectomy, splenic cells can seed within the peritonealcavity and enlarge into functional masses of splenic tissue Thesplenic nodules/masses can be found anywhere in the perito-neal cavity Extra-abdominal splenosis in the thoracic cavity isalso described Such nodules may mimic other pathology (e.g.,lymphoma) and can result in complications such as torsion orrecurrence of hemolytic disease after splenectomy

sur-Rotation Abnormalities and Heterotaxy Syndrome

In complete situs inversus, the splenic tissue is located in theright upper quadrant and the liver in the left upper quadrant.All the vascular structures and solid organs are inverted in amirror image of the norm In such cases, one may find multiplesplenules on the right instead of a spleen (▶Fig 10.15)Heterotaxy syndrome is characterized by visceral mal-position and indeterminate atrial arrangement This spectrum

of conditions is generally rather simply classified as heterotaxysyndrome with asplenia or heterotaxy syndrome with polysple-nia, although patients with heterotaxy syndrome may not fitinto either category, and a number of anomalies may be present

in both groups

Table 10.2 Splenic length in childhood

Spleen length (cm) Spleen length (cm)Age and sex Number Mean SD Min-max Age and sex Number Mean SD Min-maxAge and sex Number Mean SD Min-max Age and sex Number Mean SD Min-max

F, female; M, male; SD, standard deviation

Source: Robben S Van Rijn R Normal values In: Differential diagnosis in Paediatric Radiology Stuttgart: Thieme Medical Publishers 2001:636–637

Spleen

Fig 10.14a–d Wandering spleen presenting with torsion and focal infarction in an infant a Longitudinal panoramic view of the lower abdomen andpelvis demonstrating the displaced enlarged spleen in the pelvis (white arrow), extending behind the bladder (black arrow) b, c Color Doppler axial andlongitudinal views of the vascular pedicle with whirlpool appearances (arrows) d Focal hypoechoic areas in the upper pole with absence of Dopplersignal are in keeping with areas of infarction (arrows).

| 11.05.15 - 18:18

Fig 10.15a–e Situs inversus with multiple splenules/polysplenia a Plain chest X-ray demonstrating dextrocardia with a left-sided liver b Transverseultrasound of the left upper quadrant demonstrating a left-sided liver that is a mirror image of normal c Left-sided transverse ultrasound imageshowing the gallbladder (black arrow) located in the left upper quadrant d, e Longitudinal images of the right upper quadrant demonstrating multipleright-sided splenunculi (arrows) As the spleen develops in the dorsal mesogastrium, these would be located on the same side of the stomach

Spleen

In heterotaxy syndrome with asplenia, as the name suggests,

there is absence of the spleen or splenic tissue This is also

referred to as right-sided isomerism In the chest, the bronchial

tree follows the right-sided pattern bilaterally, and there are

bilateral systemic atria Complex cardiac malformations are

common The spectrum of abnormalities in the abdomen

includes absence of the spleen, a midline location of the liver,

an indeterminate position of the stomach, and a location of the

aorta and inferior vena cava on the same side of the spine

Clinically, apart from all the issues related to the above

anoma-lies, the absence of splenic tissue predisposes such children to

sepsis

In heterotaxy syndrome with polysplenia, multiple small

spleens/splenunculi are seen, with no large single splenic organ

(▶Fig 10.16 and▶Fig 10.17) This is also referred to as

bilat-eral left-sidedness or left isomerism because the bronchial tree

follows the left-sided pattern and there are usually bilateral

pulmonary atria The spectrum of abnormalities in the

abdo-men include a central liver, indeterminate position of the

stom-ach, extrahepatic biliary atresia, interruption of the inferior

vena cava with continuation of the azygos system, and the

pres-ence of common celiac and mesenteric arteries In 90% of cases,

cardiovascular anomalies are present There are described cases

in which other features of left isomerism are present without

an increased number of spleens The accessory splenic tissue

does not necessarily have to lie in the left upper quadrant but

may even be seen in the right upper quadrant dependant on

the location of the stomach These splenic anomalies in

hetero-taxy syndromes can be explained from an embryological

aspect It has been demonstrated that splenic tissue precursors

exist at both sides of the midline but, in normal cases, there is

preferential unilateral development of the left sided tissue

Therefore, in bilateral left sidedness one would expect the end

result to be increased/accessory splenic tissue In bilateral right

sidedness the end result would be the absence of splenic tissue

The incidence of malrotation and nonrotation (▶Fig 10.17)

is increased throughout the spectrum of heterotaxy syndromes

Abnormal Location of a Normal Spleen

Secondary to Disease

Occasionally, the spleen can be displaced from its normal

location by other pathologic processes, such as left-sided

ret-roperitoneal masses ▶Fig 10.18 demonstrates a normal

spleen displaced by neuroblastoma in a 2-year-old child The

normal spleen never returned to its normal location, even

after treatment

10.2.2 Abnormalities of Size

Enlargement of the spleen is a nonspecific finding A small

number of children can have a normal palpable spleen under

the rib margin Abnormalities in the splenic size may be

sec-ondary to generalized enlargement of the spleen or to focal

Generalized Splenomegaly

In generalized splenomegaly, the spleen increases in size in allplanes, but elongation is evident mostly in the craniocaudaldimension Measurements should be obtained as demonstrated

in▶Fig 10.13 Indications of enlargement include a rounded,bulky lower splenic pole and extension of the spleen beyondthe lower pole of the left kidney Given the constant gradualincrease in size with growth in children, unlike in the adultpopulation, it is less useful to classify causes of enlargementaccording to the degree of splenomegaly Pathologically, themost common causes of splenomegaly are infection(▶Fig 10.19), malignancy, hemolytic anemia (▶Fig 10.20),storage disorders, and portal hypertension (▶Fig 10.21)

▶Table 10.3 outlines the most common causes of splenomegaly

in children

Focal/Localized Abnormalities

Splenic CystsSimple cysts in the spleen are often identified incidentally,although when large, these can present with splenomegaly ormass effect Cysts in the spleen can be congenital or acquired(see box Possible causes of cysts in the spleen) Congenitalcysts are also referred to as epithelial or epidermoid cysts Onultrasound, these typically appear as well-defined, round oroval, anechoic thin-walled areas with posterior acoustic shad-owing surrounded by normal splenic tissue Internal echoes canalso be demonstrated On interrogation with Doppler ultra-sound, there is an absence of blood supply within these lesions.Congenital cysts can be detected antenatally, and it can be quitechallenging to be specific about the anatomical location of thecyst (▶Fig 10.22 and▶Fig 10.23)

Table 10.3 Causes of pediatric generalized splenomegalyCause Examples

Infection Viral infection (e.g., Epstein–Barr virus)

Bacterial infection (e.g., tuberculosis, brucellosis;

▶Fig 10.19)Fungal infection (e.g., candidiasis)Protozoal infection

Hematopoieticconditions

Abnormal red blood cells (e.g., spherocytosis;

▶Fig 10.20)Hematopoietic activity of the spleenMalignancy Lymphoma, either generalized enlargement or

focal lesions; typically hypoechoic lesions with noDoppler within (▶Fig 10.32)

Storage disorders Gaucher syndrome; Niemann–Pick diseasePortal hypertension Most frequent in cases of previous portal vein

thrombosis (▶Fig 10.21)

| 11.05.15 - 18:18

Fig 10.16a–c Heterotaxy syndrome with polysplenia in a 15-year-old a Reformatted coronal computed tomographic (CT) scan demonstrating anormal left-sided cardiac apex (white arrow), a left-sided liver, and a right-sided stomach (black arrow) b Reformatted coronal CT scan demonstratingmultiple small splenules (splenunculi) in the right upper quadrant (arrows) c Equivalent right-sided longitudinal ultrasound image demonstrating thesame splenules in the right upper quadrant (arrows)

Spleen

Fig 10.17a–d Heterotaxy syndrome with polysplenia in a neonate a Chest X-ray demonstrates dextrocardia A bilateral left-sided bronchial patterncan be seen b Midline transverse ultrasound image demonstrating a central liver c Oblique coronal ultrasound image demonstrating numerous

adjacent splenules in the left upper quadrant (arrows) d Image from barium follow-through examination demonstrating a left-sided stomach and

nonrotation of the bowel, with the small bowel located in the right side of the abdomen

○Secondary to infection: pyogenic abscess, echinococcosis,

fungal microabscesses (small and multiple;▶Fig 10.25)

○Secondary to traumatic contusion (▶Fig 10.24)

○Secondary to previous splenic infarction

○Cystic benign tumor (e.g., hemangioma)

○Lymphangioma (may appear as predominantly cystic,

characteristically with septa;▶Fig 10.28)

○Pancreatic pseudocyst

●Cystic metastasis (rare)

Acquired cysts (pseudocysts) may be the end result of a matic contusion, infection, or infarction (▶Fig 10.24) Patientswith traumatic cysts would be expected to have a relevanthistory, and previous imaging at the time of trauma may beavailable, although not always The ultrasound appearance ofthese can be completely identical to that of true congenitalsplenic cysts Cysts that are clearly thick-walled and/or containirregular contents are more likely to be infective One furtherconsideration would be a simple cyst that has subsequentlybled

trau-Pyogenic Splenic Abscesses

A pyogenic splenic abscess can result from focal infection in thespleen with secondary necrotic breakdown into an infectedcyst Secondary septic abscesses in the spleen are described in amyriad of distant infections (e.g., subacute bacterial endocardi-tis, urinary tract infections, respiratory tract infections) Sec-ondary infection may also develop in a previously sterile cyst,

in a splenic infarct, or in a traumatic hematoma The historyand previous imaging can help in this scenario Patients withhemoglobinopathies are at increased risk for splenic abscesses.Findings suggesting infection are an ill-defined complex cystwith heterogeneous echogenic contents and possibly septa inthe context of a child with sepsis

Multiple AbscessesFungal microabscesses typically show up as multiple tiny, hypo-echoic cystic areas in the spleen (▶Fig 10.25) In the correctclinical context, such as a child with febrile neutropenia, suchappearances are very characteristic and should be activelysought This may not be appreciated unless the organ is care-fully assessed with a higher-frequency probe

Solid Focal Heterogeneities in the Spleen (Solid Splenic Abnormalities)

The majority of solid masses in the spleen in children is benign

▶Table 10.4 outlines the differential diagnosis for hypoechoicand hyperechoic solid lesions in the spleen The following sec-tion describes in detail some of the most common causes

Hemangiomas

Hemangiomas are nonencapsulated vascular channels of ble size that are thought to arise congenitally They are most

varia-Fig 10.18a,b Abnormal location of a normal spleen after resection of a

large intra-abdominal neuroblastoma a Axial T2 magnetic resonance

(MR) image showing the location of the spleen (white arrows) to be

medial to the normal, expected position Note residual disease in the

left paraspinal region (black arrow) b MR imaging ADC (apparent

diffusion coefficient) map showing normal, expected restricted

diffusion of the spleen (arrows)

Spleen

Fig 10.19a–d Confirmed brucellosis in a 10-year-old a, b Coronal oblique ultrasound images of the left upper quadrant demonstrating a significantlyenlarged spleen (measuring up to 17 cm) Note that the distal pole of the spleen extends beyond the lower pole of the left kidney (arrows).

c Longitudinal ultrasound image of the gallbladder demonstrating associated marked edema of the gallbladder wall (arrows) d Transverse image atthe liver hilum demonstrating associated periportal lymphadenopathy (arrows)

| 11.05.15 - 18:18

Table 10.4 Solid lesions of the spleen

Hypoechogenic solid lesions Hyperechogenic solid lesions

● Hemangioma (hypervascular on Doppler;▶Fig 10.27)

● Hamartoma (▶Fig 10.30)

● Inflammatory pseudotumor (hypervascular)

● Vascular tumors (with heterogeneous appearances), such as

hemangioendothelioma (▶Fig 10.31), lymphoma (▶Fig 10.32;

Video 10.32), leiomyoma (▶Fig 10.33), Langerhans cellhistiocytosis (▶Fig 10.36)

● Peliosis

● Storage disorders (e.g., Gaucher disease)

● Infarction (may mimic mass in early stage)

● Infection (before breakdown into abscess may mimic a mass)

●Calcifications (see box Causes of focal calcifications in the spleen(may be single or multiple))

●Hemangioma (▶Fig 10.26)

●Lymphangioma (▶Fig 10.28)

●Vascular tumors (with heterogeneous appearances), such ashemangioendothelioma (▶Fig 10.31)

●Storage disorders (rarely increased echogenicity)

●Acute hematoma (may mimic hyperechoic mass lesion;▶Fig 10.38)

Fig 10.21a–c Splenomegaly in a 14-year-old with portal hypertension a Coronal oblique ultrasound image of the left upper quadrant demonstrating

a significantly enlarged spleen (measuring up to 18 cm) b Coronal oblique ultrasound image at the liver hilum showing enlargement of the portal vein(arrows) c Doppler ultrasound evaluation of the falciform ligament demonstrates venous flow, in keeping with venous recanalization (arrow)

Spleen

often small and identified incidentally, but they may be large

and complicated by excess red blood cell breakdown The

ultra-sound appearances are nonspecific, and these masses most

commonly appear hyperechoic in comparison with the rest of

the spleen (▶Fig 10.26) They may also appear hypoechoic

(▶Fig 10.27) or isoechoic, or rarely as cystic lesions

Hemangi-omas typically demonstrate increased Doppler flow

Lymphangiomas

Pathologically, lymphangiomas consist of abnormal dilated cular channels of the lymphatic system They can occur in isola-tion, involving only the spleen (▶Fig 10.28), or can be multiple

vas-or part of a mvas-ore generalized process referred to as giomatosis (▶Fig 10.29) Focal lymphangiomas can havevarying appearances on ultrasound, depending on the size ofthe cystic spaces containing lymph Typically, such lesions dem-onstrate septate hypoechoic cystic areas, as in other regions ofthe body, or less commonly are seen as solid, hyperechoicabnormalities (microcystic, in which case the cysts are not wellappreciated) Calcifications may occasionally be seen in thesepta/walls of the lesion

lymphan-Splenoma/Hamartoma

This is the most common benign tumor mass in the spleen,thought pathologically to consist of unorganized vascular chan-nels with intervening disorganized stroma with or withoutlymphoid follicles The ultrasound appearances are nonspecific,and such masses can appear hyper- or hypoechoic on ultra-sound Hamartomas can have cystic elements and calcifications.There is retained blood supply on interrogation of the solidcomponents with Doppler ultrasound (▶Fig 10.30)

Other Vascular Tumors of the Spleen

Because it is such a vascular organ, the spleen is affected by anumber of tumors of vascular origin Littoral cell angiomasand hamartomas (see above) occur in the spleen Other hyper-vascular tumors described include hemangioendothelioma(▶Fig 10.31), sclerosing angiomatoid nodular transformation,and angiosarcoma (malignant outcome)

Splenic Focal Abnormalities Associated with Storage Disorders

Rare storage disorders such as Gaucher disease and Newman–Pick disease can involve the spleen Focal splenic ultrasoundlesions are identified These appear as hypoechoic, hyperechoic,

or mixed hypo- and hyperechoic abnormalities and can alter inappearance with treatment

Lymphoma

The spleen can be involved in lymphoma Appearances are able and nonspecific, either with a generalized increase in thesize of the organ or with focal single or multiple masses appre-ciated on ultrasound Focal masses generally appear hypoechoicand can be hypovascular when interrogated with Doppler ultra-sound (▶Fig 10.32)

vari-Tips from the Pro

●When a solid lesion is identified in the spleen, evaluate theDoppler characteristics of the mass This may help shortenthe differential diagnosis Absence of Doppler signal does not

Fig 10.22a,b a Longitudinal ultrasound of a neonate with a cyst at the

splenic hilum (arrows) This was detected on antenatal scans Note the

absence of Doppler signal within the cyst b Axial T2 magnetic

resonance image demonstrates the location of the cyst in the medial

aspect of the splenic hilum (arrows) It can be difficult to identify the

organ of origin of such a cyst if the cyst is not surrounded by a rim of

normal tissue from the organ of origin

| 11.05.15 - 18:18

Fig 10.23a–d Sixteen-year-old with learning disabilities and long-term issues with swallowing a Abdominal radiograph from a barium follow-throughseries shows evident splenomegaly (arrows) and displacement of the duodenum and small bowel to the right b, c Transverse ultrasound imagesdemonstrating a large complex cystic lesion in the spleen (arrows) with posterior acoustic enhancement d Coronal oblique image of the samecomplex cyst (arrows) The spleen was subsequently removed, and the cyst proved to be a congenital epidermoid cyst

Spleen

Fig 10.24 Coronal oblique ultrasound image showing a complex

posttraumatic splenic cyst with echogenic cellular contents (arrows) in

a 14-year-old patient

Fig 10.25a,b Fungal microabscesses in the spleen Three-year-old immunosuppressed child with persistent fever (a) Coronal oblique image of thespleen obtained with a curvilinear probe (b, c) Images obtained with a higher-frequency planar probe (continued)

| 11.05.15 - 18:18

Fig 10.25c–e (continued) (d) Higher-frequency image with color Doppler interrogation Multiple focal hypoechoic areas are diffusely spreadthroughout the spleen These were subsequently shown to represent Candida microabscesses (e) Eight-year-old girl with confirmed Candidainfection Higher-frequency image of the lower pole of the spleen demonstrates a focal, well-defined hypoechoic area containing centralechogenicities that probably represent early calcifications

Spleen

Fig 10.26a–c Four-year-old girl with a typical splenic hemangioma a Coronal oblique curvilinear probe ultrasound image b Coronal oblique frequency ultrasound image These images demonstrate a focal round area of increased echogenicity within the splenic lower pole (arrows).

higher-c Transverse higher-frequenhigher-cy ultrasound image with Doppler interrogation demonstrates inhigher-creased Doppler blood flow within the hemangioma

(arrows)

| 11.05.15 - 18:18

Fig 10.27a–c Twelve-year-old girl with an incidental splenic hemangioma a Coronal oblique curvilinear probe ultrasound image b Coronal obliquehigher-frequency ultrasound image These images demonstrate a focal round area of slightly decreased echogenicity within the center of the spleen(arrows) c Transverse higher-frequency ultrasound image with Doppler interrogation demonstrates increased Doppler blood flow within thehemangioma (arrows)

Spleen

| 11.05.15 - 18:18

Calcifications in the Spleen

Calcifications are commonly identified in the spleen on

ultra-sound examination These appear as focal echogenicities that

demonstrate posterior acoustic shadowing and are commonly

multiple, although they can be seen in isolation When

identi-fied, calcifications are nonspecific, although they most likely

arise from an infective cause such as histoplasmosis

(▶Fig 10.34), previous tuberculosis infection, previous fungal

infection (▶Fig 10.35) or from Langerhans cell histiocytosis

(▶Fig 10.36) The Box Causes of focal calcifications in the

spleen (may be single or multiple) outlines the broader di

ffer-ential diagnosis for calcifications in the spleen

Causes of focal calcifications in the spleen (may be single or multiple)

●Previous infection (typically small multifocal calcifications),such as

○histoplasmosis (▶Fig 10.34)

○Tuberculosis/atypical mycobacterial infection

○Candida albicans infection (▶Fig 10.35)

○Brucellosis

○Echinococcosis

○Toxoplasmosis

○Viral infection (e.g., cytomegalovirus infection, rubella)

○Human immunodeficiency virus (HIV) infection (typicallyvascular)

○Cat-scratch disease (Bartonella)

○Previous pyogenic abscess

●In association with vascular tumors (e.g., hemangioma,lymphangioma, inflammatory pseudotumor)

●After trauma/hematoma

●After infarction

●Langerhans cell histiocytosis (▶Fig 10.36)

●Sickle cell disease

10.2.3 Traumatic Injury of the Spleen

The spleen is one of the most commonly affected organs inabdominal trauma Traumatic injury of the spleen can resultfrom a number of mechanisms In children, it is most com-monly related to motor vehicle accidents, falls, and sports(including bicycle riding) Pathophysiologically, blunt traumacan result in a torsional movement related to the relative mobil-ity of the spleen on its ligaments This can lead to injury of theblood supply at the hilum, with hematoma formation in thislocation (▶Fig 10.37) Alternatively, the spleen can be injured

by compression from the rib cage or direct penetration fromfractured ribs Finally, iatrogenic injury during surgery is alsoinfrequently identified

Splenic hematomas/contusions are focal microscopic chymal lesions Lacerations are linear areas of disruption withinthe structure of the spleen These can extend to the splenicmargin and the splenic capsule may remain intact or be dis-rupted Hematomas are often associated with lacerations andcan be contained by an intact capsule (referred to as a sub-capsular hematoma) If a laceration extends across two surfaces

paren-of the spleen, it is referred to as a splenic rupture The presence

of hemoperitoneum suggests capsular rupture

On ultrasound, hematomas/contusions (▶Fig 10.38) are seen

as areas of altered echogenicity with no vascular flow within Inthe initial stages, they appear as hyperechoic oval areas andbecome hypoechoic as they resolve Lacerations are seen as lin-ear areas of hypoechogenicity often extending to the capsularmargin (▶Fig 10.38 and▶Fig 10.39) In traumatic injury of

Fig 10.29a,b Three-year-old boy with lymphangiomatosis a Coronal

oblique curvilinear probe ultrasound image of the spleen demonstrates

a heterogeneous echotexture throughout the organ b Axial T2

blade-triggered magnetic resonance image demonstrates abnormal

serpigi-nous high signal throughout the spleen Abnormal soft tissue of similar

signal is seen in the retrocrural spaces (arrows)

Spleen

Fig 10.30a–c Eleven-year-old child with an incidental splenic hamartoma a Coronal oblique curvilinear probe ultrasound image of the spleen

demonstrates a focal, heterogeneous, mostly hypoechoic lesion in the subdiaphragmatic portion of the spleen (arrows) b Higher-frequency planarprobe image better shows the slight heterogeneity within this lesion c Power Doppler interrogation of this area of the spleen demonstrates retainedblood supply within the mass

| 11.05.15 - 18:18

Fig 10.31a–e Three-year-old boy with confirmed hemangioendothelioma involving the liver and spleen a Axial ultrasound image demonstrating thelesion in the spleen (calipers) b Coronal oblique image demonstrating the same mass arising from the lower pole of the spleen (arrows) This has aheterogeneous appearance with some focal hypoechoic areas within it c, d Appearances of the masses in the liver and spleen on axial T1 and T2magnetic resonance imaging e The splenic lesion on an anterior coronal T2 image

Spleen

Fig 10.32a–d Eleven-year-old boy with lymphoma Coronal oblique ultrasound image (a) and transverse ultrasound image (b) demonstrate multiplefocal hypoechoic lesions (arrows) c High-frequency planar ultrasound image with Doppler interrogation demonstrates absence of Doppler flow withinthese lesions d: Corresponding computed tomographic scan also shows lymph nodes at the liver hilum (arrows).

| 11.05.15 - 18:18

Fig 10.33a,b Leiomyoma of the spleen Transverse (a) and coronal (b)

oblique images from an 8-month-old boy with an incidental,

well-defined, heterogeneous, mainly hypoechoic mass in the spleen

(arrows) The ultrasound appearances are suggestive of a hamartoma

However, at partial splenectomy, this lesion was found to be a

leiomyoma

Fig 10.34a,b Eleven-year-old child with confirmed histoplasmosis

a Coronal oblique ultrasound image of the spleen with a standardcurvilinear probe shows multiple focal echogenicities (arrows) in thespleen, in keeping with small, calcified foci b Detailed ultrasoundimage with planar higher-frequency probe better appreciates theposterior acoustic shadowing, characteristic of calcifications (arrow)

Spleen

Fig 10.35a–d Ten-year-old girl with a history of previous leukemia and fungal infection a, b Coronal oblique ultrasound images of the spleen with astandard curvilinear probe demonstrate multiple focal calcifications in the spleen (arrows) c Similar appearances on an image obtained with a higher-frequency planar probe (arrow, calcification) d On a transverse ultrasound image of the epigastric region, the liver has a similar appearance, with morediffuse calcified foci.

| 11.05.15 - 18:18

the spleen, fluid/hemorrhage is often seen around the spleenitself and tracking down to the pelvis along the left paracolicgutter The presence of fluid further confirms that the intra-splenic abnormalities identified are likely traumatic in origin(▶Fig 10.38) Vascular injury can lead to traumatic pseudoa-neurysms (▶Fig 10.39) and assessment of the spleen withcolor Doppler is important in the setting of trauma and theimmediate aftermath Previous injury to the spleen can presentlate as intraparenchymal cysts

Although computed tomography is considered the gold dard for assessing the spleen in the setting of trauma, ultra-sound has a major role in assessing the spleen in the stablechild with trauma If the splenic parenchymal echogenicity andcolor Doppler appearance are normal and free fluid/hemoperi-toneum is absent, splenic injury is unlikely

stan-10.3 Acknowledgements

We would like to thank the following radiologists for sharingcases published in this chapter: Dr Erik Beek (Utrecht, TheNetherlands); Prof Jean-Francois Chateil (Bordeaux, France);

Dr Pablo Caro (Dublin, Ireland); Dr Veronica Donoghue (Dublin,Ireland); Dr Ingmar Gassner (Innsbruck, Austria); Dr KieranMcHugh (London, United Kingdom); Prof Rick R Van Rijn(Amsterdam, The Netherlands); and Dr Marina Vakaki (Athens,Greece) We would also like to thank Mr David Adams (Aber-deen, United Kingdom) for help with the anatomical drawings

Fig 10.36a,b One-month-old infant with confirmed Langerhans cell

histiocytosis a Coronal oblique ultrasound image of the spleen

demonstrates a group of adjacent small calcifications (arrow) located

within the central area of a slightly hypoechoic mass close to the

splenic hilum Note the associated posterior acoustic shadowing b

More detailed ultrasound image obtained with a higher-frequency

planar probe better appreciates the hypoechoic mass (arrows) with

multiple central calcifications

Spleen

Fig 10.37a–d Perisplenic hematoma in a 14-year-old girl with blunt abdominal trauma a Coronal oblique ultrasound image demonstrates focal areas

of decreased echogenicity in the splenic hilum, representing perisplenic hematoma (arrows) b Coronal oblique ultrasound image of the lower pole ofthe spleen demonstrates further fluid, with some septa around this area (arrows) c Transverse ultrasound image demonstrates the appearance of theperisplenic hematoma in this different plane (arrows) d Coronal oblique ultrasound image with color Doppler demonstrates normal Doppler signal inthe splenic parenchyma

| 11.05.15 - 18:18

Fig 10.38a–d Ten-year-old boy with blunt abdominal trauma a Coronal oblique ultrasound image demonstrates a focal area of increasedechogenicity, in keeping with a small hematoma (white arrows) The associated adjacent area of low echogenicity is in keeping with a laceration (blackarrows) b Transverse ultrasound image of the spleen shows the laceration (white arrows) to extend to the splenic hilum (black arrow) c Coronal obliqueultrasound image with color Doppler interrogation demonstrates an absence of color Doppler flow within the area of the laceration (white arrows)

d Coronal oblique ultrasound image of the splenic lower pole demonstrates associated free fluid (white arrows) around the spleen, which is commonlyseen in the context of traumatic changes in the splenic parenchyma

Spleen

Fig 10.39a–c Splenic pseudoaneurysm and laceration in a 14-year-old boy with blunt abdominal trauma a Coronal oblique ultrasound image

demonstrates a well defined focal oval area of decreased echogenicity in the splenic parenchyma (white arrow) just adjacent to a larger, more poorlydefined area of subtly decreased attenuation (black-rimmed arrows) b Same image with color Doppler interrogation demonstrating increased

| 11.05.15 - 18:18

Recommended Readings

Abbott RM, Levy AD, Aguilera NS, Gorospe L, Thompson WM From the archives of

the AFIP: primary vascular neoplasms of the spleen: radiologic-pathologic

corre-lation Radiographics 2004; 24: 1137 –1163

Al Ahmad A, Jourabian M, Pipelzadeh M Splenorenal fusion in a 26-month-old girl.

Pediatr Radiol 2009; 39: 735 –738

Applegate KE, Goske MJ, Pierce G, Murphy D Situs revisited: imaging of the

hetero-taxy syndrome Radiographics 1999; 19: 837–852, discussion 853–854

Benter T, Klühs L, Teichgräber U Sonography of the spleen J Ultrasound Med 2011;

30: 1281 –1293

Berrocal Frutos T, del Pozo Garcia G, Albillow Merino JC The abdomen and

gastro-intestinal tract In: van Rijn RR, Blickman JG, eds Differential Diagnosis in

Pediat-ric Imaging New York, NY: Thieme Medical Publishers; 2011:167–172

Brook I, Frazier EH Microbiology of liver and spleen abscesses J Med Microbiol

1998; 47: 1075 –1080

Brown CV, Virgilio GR, Vazquez WD Wandering spleen and its complications in

chil-dren: a case series and review of the literature J Pediatr Surg 2003; 38: 1676 –

1679

Chippington S, McHugh K, Vellodi A Splenic nodules in paediatric Gaucher disease

treated by enzyme replacement therapy Pediatr Radiol 2008; 38: 657–660

Doria AS, Daneman A, Moineddin R et al High-frequency sonographic patterns of

the spleen in children Radiology 2006; 240: 821 –827

Duddy MJ, Calder CJ Cystic haemangioma of the spleen: findings on ultrasound and

computed tomography Br J Radiol 1989; 62: 180–182

Hwajeong L, Koichi M Hamartoma of the spleen Arch Pathol Lab Med 2009;

133:147(96);151

Hollingsworth CL, Rice HE Hereditary spherocytosis and partial splenectomy in

chil-dren: review of surgical technique and the role of imaging Pediatr Radiol 2010;

40: 1177–1183

Gozman A Pediatric splenomegaly In: Arceci RJ, ed Medscape http://emedicine.

medscape.com/article/958739-overview Accessed February 22, 2014

Impellizzeri P, Montalto AS, Borruto FA et al Accessory spleen torsion: rare cause of

acute abdomen in children and review of literature J Pediatr Surg 2009; 44: e15 –

e18

Kanwar VS, Aceci RJ Pediatric splenomegaly Medscape Radiology Available online

at: www.emedicine.com/article/958739

Karaman MI, Gonzales ET, Jr Splenogonadal fusion: report of 2 cases and review of

the literature J Urol 1996; 155: 309 –311

Komatsuda T, Ishida H, Konno K et al Splenic lymphangioma: US and CT diagnosis and clinical manifestations Abdom Imaging 1999; 24: 414–417

Körner M, Krötz MM, Degenhart C, Pfeifer KJ, Reiser MF, Linsenmaier U Current role

of emergency ultrasound in patients with major trauma Radiographics 2008; 28:

225 –242 Lachman RS Taybi and Lachman ’s Radiology of Syndromes, Metabolic Disorders and Skeletal Dysplasias 5th ed Philadelphia, PA: Mosby Elsevier; 2007:63 –65 and 645–647

Lee H, Maeda K Hamartoma of the spleen Arch Pathol Lab Med 2009; 133: 147–151 Lynn KN, Werder GM, Callaghan RM, Sullivan AN, Jafri ZH, Bloom DA Pediatric blunt splenic trauma: a comprehensive review Pediatr Radiol 2009; 39: 904 –916, quiz

1029 –1030 Mathurin J, Lallemand D Splenosis simulating an abdominal lymphoma Pediatr Radiol 1990; 21: 69–70

Paterson A, Frush DP, Donnelly LF, Foss JN, O’Hara SM, Bisset GS, III A ented approach to splenic imaging in infants and children Radiographics 1999; 19: 1465 –1485

pattern-ori-Patterson KD, Drysdale TA, Krieg PA Embryonic origins of spleen asymmetry opment 2000; 127:167-175

Devel-Pomara G Splenogonadal fusion: a rare extratesticular scrotal mass Letter to the editor Radiographics 2004; 24:417

Poulin EC, Thibault C The anatomical basis for laparoscopic splenectomy Can J Surg 1993; 36: 484 –488

Riera M, Buczacki S, Khan ZAJ Splenic regeneration following splenectomy and impact on sepsis: a clinical review J R Soc Med 2009; 102: 139–142

Robben S Van Rijn R Differential diagnosis in Paediatric Imaging Sttutgart: Thieme Medical Publishers 2001:625-659

Schoenwolf GC, Bleyl SB, Brauer PR, Francis-West PH Development of the intestinal tract In: Larsen ’s Human Embryology 4th ed Philadelphia, PA: Church- ill Livingstone Elsevier; 2009:435–477

gastro-Standring S, Borley NR, Healy JC, Collins P, Wigley C, The Spleen In: Gray’s Anatomy: The Anatomical Basis of Clinical Practice 40th ed Philadelphia, PA: Churchill Liv- ingstone Elsevier; 2008:1191 –1195

Toma P, Granata C, Rossi A, Garaventa A Multimodality imaging of Hodgkin disease and non-Hodgkin lymphomas in children Radiographics 2007; 27: 1335 –1354 Wadsworth DT, Newman B, Abramson SJ, Carpenter BL, Lorenzo RL Splenic lym- phangiomatosis in children Radiology 1997; 202: 173–176

Xu WL, Li SL, Wang Y, Li M, Niu AG Role of color Doppler flow imaging in applicable anatomy of spleen vessels World J Gastroenterol 2009; 15: 607 –611

Spleen

Chapter 11

Pediatric Intestinal Ultrasonography

| 11.05.15 - 18:18

11 Pediatric Intestinal Ultrasonography

Simon Robben

Ultrasonography (US) is the imaging modality of choice for the

initial evaluation of intestinal diseases in children for many

reasons:

●It is relatively inexpensive

●It is patient-friendly

●It lacks radiation and motion artifacts

●The small size of the child compensates for the limited

penetration of sound waves

●The small size of the child facilitates the use of

high-frequency transducers

●US involves direct contact with the patient, offering a unique

opportunity to ask specific questions and perform additional

physical examination, emphasizing the role of the radiologist

as a clinician

●Flow studies are possible with the Doppler mode

●Real-time imaging allows visualization of movements (e.g.,

peristalsis)

Actually, US has become the most important imaging technique

in children and can be considered the workhorse of pediatric

radiology

Initially, US of the stomach and intestines was not popular for

obvious reasons: bowel gas has the annoying characteristic of

reflecting all sound waves or creating artifacts because of its

abnormally low acoustic impedance However, increased

knowledge, improved technique (e.g., graded compression),

improved hardware (high-frequency transducers), and

improved software (adaptive imaging, compound imaging)

have changed this concept Nowadays, it is impossible to

imag-ine US without intestinal US, especially in pediatrics!

The hallmark of intestinal ultrasonography is the“gut

signa-ture.” This is the characteristic appearance of the layers of the

gut (▶Table 11.1;▶Fig 11.1) The wall of the intestine is

con-sidered stratified when the submucosal echogenicity is present

and the mucosa, submucosa, and muscularis propria are

sepa-rately visible Nonstratification means indistinctness of the

mucosa and submucosa or of all layers

Here are some practical tips for a successful intestinal

ultra-sonographic examination:

●Have patience Infants have limited sympathy for the

work-load of a pediatric radiologist

●Use graded compression whenever necessary, always

realiz-ing that children are not as delicate as porcelain (▶Fig 11.2;

Video 11.2) If they can withstand vaginal delivery, they can

tolerate serious graded compression

●Use warm ultrasound gel It is almost unimaginable how apeacefully sleeping infant can be turned into a raging beastsolely by administering cold gel to its belly

●Take advantage of domestic sedation whenever possible Apacifier with a few drops of syrup will do the trick The infantwill stop crying and relax the abdomen We have syrup inevery US room Some parents object to the administration ofnonsterile, cariogenic, obesity-inducing drugs that inevitablywill lead to overindulgence For these reluctant parents, ster-ile sucrose (24%) is available in the neonatal intensive careunit in single-patient twist cap vials for the same purposeand the same results at a greater expense (▶Fig 11.3)

●Start the examination with a structure that always will berecognized—the descending colon That will give youconfidence

●A small amount of peritoneal fluid at the base of the cecumand behind the bladder is physiologic in children

●Try to hold the transducer still for a while, and try to ate the bowel movements (or absence of peristalsis) and thepassage of gas bubbles through vessels or a fistula Gentlecompression of the transducer at a fixed position will revealfluctuation of unexpected pus

appreci-●Make liberal use of color Doppler US It may reveal the solidnature of hypoechoic infiltrates or lymph nodes (simulatingfluid) and the avascularity of an apparently normal bowelloop

●Observe at least the following: length of the affected segment,wall thickness, degree of stratification, vascularity, presence

of peritoneal fluid (and its clarity), and peristalsis

●Be aware of hyperechoic islands of mesentery or omentumwith hypoechoic surroundings (▶Fig 11.4; Video 11.4) Inour experience, they are virtually pathognomonic for infiltra-tive pathology (inflammatory or neoplastic)

●Always be aware of this:“An uncommon presentation of acommon disease is more common than a common presenta-tion of an uncommon disease” (▶Fig 11.48 and▶Fig 11.49)

This chapter provides an overview of the diagnostic potential ofpediatric gastrointestinal US

11.1 Esophagus

Endoscopic US is a useful technique to evaluate the esophagealwall and its adjacent mediastinum in a variety of congenital andacquired diseases However, it is an invasive method thatrequires sedation or anesthesia and will not be discussed in thischapter on conventional US

The cervical esophagus can be visualized by conventional US

in all children as an oval structure between the trachea and tebral column It can be seen to a better advantage by using thethyroid gland as an acoustic window and rotating the head 45degrees to the opposite site (▶Fig 11.1a) The esophageal wallcan be recognized by its gut signature with five clearly definedlayers (▶Table 11.1) The mean wall thickness is 2.8 mm (range,2.2–3.8 mm) at all ages

ver-Table 11.1 Gut signature

Layer Echogenicity

Mucosal surface Hyperechoic

Mucosa Hypoechoic

Submucosa Hyperechoic

Muscularis propria Hypoechoic

Serosal surface Hyperechoic

Fig 11.1a–d Gut signature in the esophagus (arrow, a), stomach (b), ileum (c), and appendix (arrow, d) T, trachea.

| 11.05.15 - 18:18

Fig 11.3a,b Syrup (not diluted!) and pacifier (a) and a single-patient vial of 24% sucrose (b) for annoying infants

Fig 11.2a,b Juvenile polyp in the descending colon Without compression, a normal descending colon is seen filled with gas (a) Mild compressionreveals a juvenile polyp (between arrows, b)

Pediatric Intestinal Ultrasonography