Summary of medical doctoral thesis study on the efficacy of surgical treatment for recurrent retinal detachment

Evaluate the result of surgical treatment and related factors of recurrent retinal detachment MEANING AND NEW CONTRIBUTION - This is the first study of recurrent retinal detachment in

HANOI MEDICAL UNIVERSITY

BUI HUU QUANG

STUDY ON THE EFFICACY OF SURGICAL TREATMENT FOR

RECURRENT RETINAL DETACHMENT

Speciality: Ophthalmology Code: 62720157

SUMMARY OF MEDICAL DOCTORAL THESIS

HANOI – 2020

MINISTRY OF EDUCATION AND

TRAINING

MINISTRY OF HEALTH

THE THESIS WAS PRESENTED AT HANOI MEDICAL

At Hanoi Medical University

At the time of day month year 2020

The thesis can be found at:

1 Vietnam National Library

2 Library of Hanoi Medical University

BACKGROUND

Primary retinal detachment is a serious disease that is difficult to treat, its prevalence is about 1 case / 10000 people a year The disease can cause blindness if not treated properly or in case of treatment failure Since the 1970s, the introduction of vitrectomy technique has made a fundamental change in the treatment of retinal detachment (RD) However, RD is still a severe disease that is difficult to treat, and the failure rate varies according to the clinical forms of retinal detachment There may be almost no failure in the case of simple retinal detachment without vitreo-retinal proliferation (PVR) but can reach 50% in more severe forms According to Girard et al (1994), the relapse rate was about 4.75% in a study of 1136 retinal redetachment eyes in 1073 patients Recurrent retinal detachment (RRD) can occur very early after retinal detachment or later after months or years The characteristics of RRD are much more clinically complex as well as more difficult to manage

In Vietnam, there have been a number of reports on RRD that many authors mentioned clinical, etiology, treatment methods However, there has not been a comprehensive clinical study of the causes of RRD and the treatment of RRD Therefore, we conduct research topics

"Study on the efficacy of surgical treatment for recurrent retinal detachment" aim to:

1 Describe the clinical features of recurrent retinal detachment

2 Find out the causes of recurrent retinal detachment

3 Evaluate the result of surgical treatment and related factors of recurrent retinal detachment

MEANING AND NEW CONTRIBUTION

- This is the first study of recurrent retinal detachment in Vietnam with a sufficiently large number of patients and a relatively long follow-

up period

- The study has summarized the clinical characteristics of recurrent retinal detachment quite comprehensively and the treatments corresponding to each morphology, thereby pointing out the relationships between clinical characteristics and surgical results

- The study has initially assessed the results of surgical methods to treat recurrent retinal detachment The study has drawn a number of suitable surgical indications for each particularly recurrent retinal

detachment The surgical methods applied to achieve a high rate of retinal reatachment after surgery and improved vision for patients

THESIS STRUCTURE

The thesis consists of 131 pages Introduction 2 pages, an overview

of literature 44 pages, subject and methodology 16 pages, research results 32 pages, discussion 33 pages, conclusion 2 pages, future works

1 page In the thesis, there are 31 tables, 11 charts, 6 figures, and 9 illustrations with 2 photo pages The thesis uses 105 references including 15 Vietnamese, 14 French, the rest are English, including 23 documents in the past 10 years

Chapter 1 AN OVERVIEW OF LITERATURE

1.1 Recurrent retinal detachment

1.1.1 The concept of Recurrent retinal detachment

Recurrent retinal detachment is phenominent of a RD successfully operated then because of any reason the retina was redetached The concerpt of recurrent retinal detachment is still controversy Some cases were misunderstood between recurrent retinal detachment and the failure of operation.Distintion of this different is not really clear They suposed that after a good operation, retina was reatached but some risk factors make retina redetached again, it could be considered as a recurrent retinal detachment

1.2 Clinical characteristics of recurrent retinal detachment

Time varies with each study of the different authors:

According to Foster (2002), 3 days

According to Benson (1988) before 6 weeks, after 6 weeks

According to Hilton (1989) after 6 months

1.2.1 Symptoms of recurrent retinal detachment

- Mechanical symptoms

- Physical symptoms

1.3 Causes of recurrent retinal detachment

1.3.1 The cause belongs to the tear

1.3.1.1 Missing tears

1.3.1.2 Reopen the old tear

According to Sicault (1968): 8.4% due to reopening old tear

According to Smiddy in the study of 26 cases, the author found that:

30.8% misplaced retinal tear site, 19.2% misplaced but not protruding enough to support the retina to reattache

1.3.1.3 Due to the new tear When impacted on the eyeball and the

retina DK causes the shrinkage into the retina DK as the reason of the retinal tearing

1.3.1.4 Risk factors of surgery with Recurrent retinal detchment

* Influence of chorioretinal adhesion: Cryotherapy and photocoagulation overdose

* Time of new tear formation

- Peroperative: shrinkage due to surgical operations

- Postoperative early: due to strong pulling of the air balloon, the patient's posture is not good

- Postoperative late: due to the traction of vitreoretinal proliferation

* New types of tear

* Complications during, after surgery, handle complications

1.3.1.5 Relevant factors of the patient's compliance to postoprerative posture

Follow correct postoperative posture helps to heal the tear, It is found that the inflammatory reaction will reach a maximum from day 2 to 8-

10 days after surgery

1.3.2 Cause by vitreous condition

- Shrinking vitreous body

- Transformation of vitreous body: liquerfaction of vitreous body,

- Due to the postoperative inflammatory reaction

- Due to the vitrectomy

1.3.2.1 Cause by vitreoretinal proliferation

According to the retina association since 1983, vitreoretinal proliferation is a mask of vitreous traction, preretinal membrane mask

of preretinal proliferation Vitreoretinal proliferation causes a retinal detachment complication and is the cause of 75% of surgical failure

* The hypothesis that pathogenesis of vitreoretinal proliferation is a

process similar to the process of scarring elsewhere in the body includes:

- Inflammatory phase characterized by platelet activity

- Synthesis stage: F.G.F (Fibroblast Growth Factors)

- Stage of shrinkage: due to the shrinkage, it leads to the risk of reopening treated tear and creating new ones

1.3.2.2 Risk factors causing PVR in Rhegmatogenous retinal detachment

* Favorable factors for vitreoretinal proliferation

- The degree of pigment epithelial revealed in RD: tear

- Inflammatory reaction before and after surgery

- Posterior vitreous detachment is not completely

- Time to delay RD surgery

- Hemorrhage in the vitreous, anterior chamber and under the retina

- Surgical operations such as coagulation or laser can cause PVR

* Clinical factors out of risk factors of vitreoretinal proliferation

in operation

According to Bonnet: -Increased DKVM before surgery in stage C

- The circular expansion of the tear has a flap width of 90 degrees or more

- The flanging and fixing of a flap with a flap has a risk of about 26.5%

- Black choroid before surgery, but this is still being debated

1.4 Treatment of recurrent retinal detachment

1.4.1 Rule of treatment

- The first is surgery to re-attache the retina

- The second is the treatment of vitreoretinal proliferation

1.4.2 The treatment of relapses

1.4.2.1 Examining and detecting the cause recurrent retinal detachment

1.4.2.2 Internally medical treatment

Summary of research by Ghasemi Falavarjanin et al 2014 on medical treatment of anti-inflammatory drugs, corticosteroids, restriction of inflammatory reactions, Bevacizumab usually takes 6-12 weeks

1.4.2.3 Surgical treatment

Some techniques used in RD surgery: the previous surgery may

make the changes of anatomical landmarks, scarring between the membranes

* Examination :

* Preparation for surgery

* Surgical operations:

* Causes sticky inflammatory reaction:

- Cryotherapy from outside the sclera around the tear

- Photocoagulation: also according to general principles, can use intraocular laser, or external

* External indentation

* Scleral buckling

* Drainage under the retina

* Vitrectomy: Vitrectomy is indicated in case of vitreous opacity,

vitreoretinal traction, peelling and cutting preretinal membrane

2.1.1 Selection criteria

- Patients who have rhegmatogenous retinal detachment treated, retina is attached after discharge then got a redetachment Having complete medical records of previous surgery Agreed to participate in the study

2.1.2 Exclusion criteria:

- Patients have other retinal pathologies such as diabetis retinopathy

or other cause as trauma, uveitis or other operative complication like endophthalmitis

- Children are younger than 6 years old, Old people are too old and weak combine with sever systemical deseases

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Sample size n ≈ 62 eyes

Sample selection: take a sufficient number of patients from the starting time of the study until the sample size is reached, according to patient selection criteria

2.2.3 Research facilities

2.2.3.1 Instrument for examining and evaluating results

2.2.3.2 Surgical facilities

2.2.4 Method of implementation

2.2.4.1 Evaluation before surgery

* Identify the cause of recurrent retinal detachment

Clinical morphology of recurrent retinal detachment:

* Identify the cause of retinal recurrence

Clinical morphology of BVMTP often has:

+ Open the old tear or not: observe whether the tear is located in the old scar area due to laser or freezing

+ New tear or not: usually outside the old surgical area, outside the belt + Vitreoretinal proliferation, appear sooner or later

Physical function symptoms Symptoms attached

* Subclinical

2.2.4.2 Indications for surgery

Our indications are based on a patient’s retinal detachment, specifically as follows:

- Surgical method: External scleral indentation Vitrectomy + Gaz or Silcon and combine Scleral buckle Vitrectomy + Gaz or Silicon without scleral buckle.depend on each case

2.2.4.3 Conducting surgery

2.2.4.4 Postoperative care and follow up after treatment

2.2.4.5 Management of surgical complications

- Visual acuity: we classify into the following groups

+ From LP to smaller than CF 1 meter

+ From CF 1m to <CF 3m

+ From CF 3m to 20/200

+ From 20/200 to < 20/80

+ From 20/80 to 20/40

+ From > 20/40 and above

- Vision is converted from Snellen table to logMAR table, respectively, to calculate the average value

- Intraocular pressure: Intraocular pressure is measured with a

Maclacov tonometer and divided into the following groups:

Areas of retinal detachment: Evaluation of retinal detachment areas

by quadrant: 1,2,3,4 quadrants or posterior pole retinal detachment

Macular situation: attached or detached

Number of retinal tears

Morphology of retinal tear: according to the following 5 forms:

o Tear-shaped horseshoe with a flap

o Retinal hole on degenerative background

o Giant tear

o Retinal break

o The macula hole

The location of the tear in the quadrant: the tear is located in what kind of

quadrant (upper tempral, lower tempral, upper nasal, lower nasal)

Tear size:

o Minor tear: under 1 hour arc

o Average tear: 1-3 hours arc

o Large tear: over 3 hours arc

Evaluation of vitrolretinal proliferation : according to the classification of the World Retina Society in 1983

Combined lesions: Vitreous hemorhage or choroidal detachment

2.3.3.2 Causes of recurrent retinal detachment

- Reopen the old tear – new retinant tear – vitreous retrolretinant proliferation – silicon oil under retina – macular hole

2.2.6.3 Surgical results

- Evaluating retinal attachment results

+ Attached retina: As clinically and echography retina is is completely attached from centre to periphery after 1 month postop + Not attached retina: As clinically and echography retina is detached in every level

- Evaluating visual acuity results: Corrected visual acuity was

documented at the discharge time and follow up times as same

as document before operation

– Evaluating IOP results: IOP was measured by Maclakov

tonometer and evaluation as before operation

- Complications: - As peroperation

- As postoperation later on 6 months

- Completement surgery: scleral buckle, inject heavy oil such as PFCL (Decalin)

2.2.7 Data analysis

Data were processed by SPSS 18.0 statistical software Compare the average using the T-student verification algorithm The qualitative variables are compared proportionally with the test algorithm χ2 The difference is considered to be statistically significant when p <0.05

2.2.8 Research ethics

Chapter 3 RESULT

Through a study of 62 eyes on 62 patients with recurrent retinal detachment and treated at the Department of Trauma and Vitreoretinal Department – Vietnam National Ophthalmology Hospital from January

2013 to September 2015, we obtained the following results:

3.1 Patient characteristics

3.1.1 Distribution of patients by age and gender

- There are 40 male patients, accounting for 64.5% 22 female patients, accounted for 35.5% The difference was statistically significant with p <0.05 The average age is around 49.9 ± 20 with the lowest age being 8 and the highest age being 80

3.1.2 The interval time for recurrent retinal detachment after the previous surgery

About 1-3 months after the previous surgery, there were 47 redetached eyes accounting for 75.8% In 3 to 6 months, there are 10

eyes, accounting for 16.2%, and over 6 months, 3 eyes account for 4.8% This difference is statistically significant with p <0.05

3.1.3 Time to hospitalization after the first symptoms

Patients with RRD usually admitted the hospital in about 1 week, there are 31 patients accounting for 50%, in about 1 week; there are 30 patients who came after 1 month, accounting for 48.4% The differences between the above groups are statistically significant with p <0.05

3.1.4 Number of time for previous retinal surgery

The eyes had surgery once, 40 eyes accounted for 64.5%, twice had 18 patients accounting for 29.1%, 3 times accounted for 3.2%, 4 times with

2 accounted for 3.2% The percentage of the difference between the groups has statistical significance (p <0.05)

3.1.5 Mechanical symptoms

Symptoms of blurred vision - 100% Loss and narrowing of the eyesight were seen in 41 patients (66.7%) Transfiguration symptoms accounted for 25.8%, flashing signs in 6 patients accounted for 9.7% and 20 patients showed signs of pain The differences between the above groups were statistically significant with p <0.05

3.1.6 Functional and physical symptoms

3.1.6.1 Vision condition of the patient upon admission

Among CF group <3m, account for 56.5%, 12( 19,4%) patients with HM, patients with visual acuity from CF 3m to 20/200 have 10 patients accounting for 16.1%, vision range 20 / 200 - 20/80 have 1 patient Visual acuity 20/80 - 20/60 and> 20/60 have 1 patient accounting for 1.6%

3.1.6.2 The patient's IOP at admission

Patients mainly with low IOP

38 patients accounting for 61.3% Normal eye pressure from 16 - 24mmHg (38.7%) and low eye pressure below 16mmHg The difference between the levels is statistically significant (p <0.05)

3.1.6.3 Crystalline lens condition

The IOL group had 18 eyes, accounting for 29%, the group of remained crystalline lenses had the majority with 40 eyes (64.3%), the group who had the IOL without surgery had 4 patients accounting for 6.5% The difference between the statistically significant (p <0.05)

3.1.6.4 Vitreous condition

- 50 patients (80.6%) were cloudy due to pigmentation

- 12 patients (19.4%) were cloudy due to hemorrhage

The difference between the 2 groups is statistically significant (p <0.05)

3.1.6.5 Areas of retinal detachment

Detached retinal area over 2 quadrants accounting for 90,5%, 6 patient have 1 quadrant of detached retina accouting for 9,7%

3.1.6.6 Macular condition

We found that all most of patient have detachment over macular area (89%), 6 patients have macular hole, 13 patients have no detached macular area accounting for 21% The difference between groups is statistically significant with p <0.05

3.1.6.7 Retinal lesions

* Number of tear:

38 patients with 1 tear accounted for the majority - 61.4%, 3 patients had 2 retinal tears - 8%, and 1 patient had 3 retinal tears accounting for 1.6% 18 patients have not recorded the tear accounted for 29%

* retinal tear location:

- Locating on the temporal side accounts for the majority - 73.8% of which the lower temporal side is more

* Retinal tearing and morphology:

- 29 tractioned tears is 69,05%, 8 (19,05) tears were caused by peripheral atrophy degeneration, 5(11,9%) macular holes , No case

of retinal roof break

3.1.6.8 Vitreoretinal proliferation

The stage C and above group C with 28 patients accounted for 45.1%, 21 groups of vitreoretinal proliferation in stage B, accounted for 33.9% and 13 patients in stage A, accounted for 21.5% The difference between group is statistically significant with p <0.05

3.1.7 Subclinical results

3.1.7.1 Ultrasonic

Among the 52/62 patients (83.8%) who had an ultrasonic procedure

We found that the status of mobile retina was 59.6%, retina was less and non-mobile accounted for 40.4%

3.1.7.2.Electroretinography

- 57 cases with flat completely ERG were 91,9%,

- 5 cases with sever decrease ERG

The difference between two groups is statistically significant with p <0.01

3.2 Causes of recurrent retinal detachment

3.2.1 The retinal lesions are related to the cause of RRD

- Reopening the old tear seen in 12 patients accounting for 19.4%

- New tear seen in 19 patients accounted for 30.6%

- Vitreoretinal proliferation in stage B + C in 49 patients, accounting for 79%

- There are 6 patients with macula (accounting for 9.7%)

- 3 patients with silicon oil under retina accounted for 4.8%

The difference between groups is statistically significant with p <0.05

3.2.2 Related retinal lesions and relapse time

According to the study, during the period of 1 to 3 months, there were

39 patients accounting for 46.8% (n = 62), 14 new tears (22.6%), and 9 open old tears (14.5%) At other periods there are less retinal lesions

3.2.3 Related retinal tears to vitreous causes and retinal causes

47 Tractioned tears and macular holes accounting for 75,8%,

15 Atrophy degeneration tears accounting for 24,2%

The difference between groups is statistically significant with p <0.01 3.2.4 Related surgical methods to RRD

Vitrectomy+ gaz accounting for 40,3% Drainage fluid + Gaz accounting for 21% Scleral buckling accounting for 19,4% Vitrectomy+ Gaz combined scleral buckling accounting for 3,2% Vitrectomy + silicon oil + scleral buckling accounting for 16.1%

3.3 Surgical results

3.3.1 Indication of surgical methods for the study patient group

- 38 (61,3%) patients selected for vitrectomy + gaz or silicon oil and combined with sclera buckling

- 18 (29%) patients indicated for vitrectomy + gaz or silicon oil

- 6 (9.7%) patients indicated for External indentation and drainage fluid under retina detachment

- In scleral buckle surgery: At the 1month postop time retina not reattached in 2/6 cases, there fluid under retina After 2 month postop time all most patient has retina reattached completely 6/6 However the indication for this method is not freequent in RRD treatment: 6/62 (9.7%)