Slow Coagulation Trans-Scleral Cyclophotocoagulation Versus Trabeculectomy in Medically Uncontrolled Open-Angle Glaucoma in Pseudophakic Patients
Phase: NA
Conditions: Glaucoma, Open Angle
Sponsor: Minia University

1 
 
 
 كلٌه
الطب 
 
قسم طب وجراحة العٌن                                                     
 
 
عنوان الرسالة باللغة العربية 
     
"التخثر البطيء عبر الصلبة للتخثير الضوئي للجسم الهدبي مقابل 
استئصال الشبكة التربيقية في حاالت المياه الزرقاء مفتوحة الزاوية غير المتحكم 
فيها عالجي  ا لدى المرضى الذين خضعوا 
 لزرع عدسة إصطناعية بعد إزالة عدسة
العين"
 
 
Title of the study 
 
“Slow Coagulation Trans-Scleral Cyclophotocoagulation versus 
Trabeculectomy 
in 
Medically 
Uncontrolled 
Open-Angle 
Glaucoma in Pseudophakic Patients" 
 
خطت بحث يقديت 
Protocol of a thesis  submitted 
نكهيت انطب 
to the faculty of medicine 
جايعت انًنيا 
Minia University 
 كجسء يكًم 
for partial fulfillment of the 
نهحصول عهى درجت ان
دكتوراة 
requirement of MD degree 
في طب و جراحت انعين 
in Ophthalmology 
 
يقديت ين 
 حازو يحًد يحًد عبدانعسيس 
 يدرش يساعد بقسى طب وجراحت
انعين كهيت انطب جايعت انًنيا 
 
 
By 
Hazem Mohamed Mohamed Abd El-Aziz 
Assistant lecture in ophthalmology 
department at faculty of medicine 
Minia University.  
 
   
 

2 
 
                    المشرفون         
Supervisors
 
 
Dr. Ahmed Mostafa Eid Desoky                     أ.د
. أحمد مصطفي عيد دسىقي                       
 
Professor of Ophthalmology  أستاذ طب وجراحة العٌن 
                                                 
 
Faculty of Medicine, Minia University                                         
 كلٌة الطب جامعة
المنٌا 
 
Dr. Riham Samy Hanafy Mahmoud Allam                   أ.د ريهام سامي حنفي محمىد عالم  
Professor of Ophthalmology  أستاذ طب وجراحة العٌن 
                                                 
 
Faculty of Medicine, Cairo University                                         
 كلٌة الطب جامعة
القاهرة 
 
 Dr. Mohamed Tarek A. Moustafa أ.د.م محمد طارق عبدالقاد
ر محمد 
            مصطفي      
    
  
Assisstant Professor of Ophthalmology                             
 أستاذ مساعد
طب و جراح
ة العٌن 
 
Faculty of Medicine, Minia University                                          كلٌة الطب جامعة المنٌا 
 
Dr. Amr Ahmed Mohamed Abdelrahman 
 د. عمرو أحمد محمد
عبدالرحمن                       
 
 
Lecturer of Ophthalmology                                                        مدرس طب وجراحة العٌن 
 
Faculty of Medicine, Minia University                                          كلٌه الطب جامعه المنٌا
      
      
 
 
 
 
 
 

3 
 
Introduction 
             
Glaucoma is an optic neuropathy that is characterized by progressive structural and 
functional neuropathy.(1) It is a leading cause of irreversible blindness worldwide.(2)  
Open angle glaucoma (OAG) is the commonest subtype of glaucoma. The number of 
patients diagnosed with POAG was estimated 52.68 million in 2020 and expected to be 79.76 
million in 2040.(3) 
The management of OAG in patients with pseudophakia aims to lower intraocular 
pressure (IOP), which is the major modifiable risk factor for glaucoma progression.(4) This can 
be achieved by different modalities including medical, laser or surgical methods.(5) 
In many cases medical therapy can provide an effective IOP control, while surgery and 
laser are still indicated when the medical treatment fails to lower IOP sufficiently, or if the 
patient is not compliant with treatment.(6) 
Trabeculectomy with mitomycin C (MMC) is a filtration procedure that reduces IOP by 
creating a connection between the anterior chamber and the sub-conjunctival space after excision 
of a part of the trabecular meshwork. Pseudophakic eyes with OAG have a higher risk for 
surgical failure of trabeculectomy with MMC than the phakic eyes.(7) Also it is associated with a 
higher incidence of complications as hypotony, lost anterior chamber or supra-choroidal 
effusion.(8) 
Laser therapy, as a cyclodestructive procedure, lowers IOP by reducing aqueous humor 
production. This is achieved through the application of diode laser energy to the sclera, which is 
absorbed by the melanin pigment in the ciliary processes, resulting in coagulative necrosis of the 
ciliary body. Historically, this treatment was regarded as a last-resort option for eyes with very 
limited visual potential due to the significant risks of uncontrolled inflammation and phthisis 
bulbi.(9)  
 Now, with recent advances in laser probes and laser settings, the safety of trans-scleral 
cyclo-destruction has improved, rendering it a viable non-invasive option for a broader spectrum 
of patients including those with good visual acuity (VA) and as a primary procedure in 
management of OAG with pseudophakia.(10) 
Two approaches are commonly used to deliver laser energy using continuous wave trans-
scleral cyclo-photocoagulation (CW-TSCPC): the conventional "pop" technique, where laser 
energy is initially increased until an audible, explosive, cavitating tissue-derived "pop" is heard. 
The laser power is then reduced until these pops are no longer audible. This method typically 

4 
 
begins with a laser energy setting of approximately 1750–2000 mW, applied for a short duration 
of 2 seconds,(11) and the treatment is delivered circumferentially along the limbus. In contrast, 
slow coagulation (SC) CW-TSCPC utilizes a lower amount of diode laser energy over an 
extended period, approximately 1250 mW over 4 seconds.(11, 12) 
Previous results comparing the outcomes of the slow coagulation approach with the 
conventional high-energy pop approach found a lower incidence of postoperative complications 
in the slow coagulation group and comparable IOP- lowering effects between both groups.(11) 
Although conventional CPC may have previously been reserved for blind painful eyes or eyes 
which have already failed prior glaucoma surgery, recent literature supports slow coagulation 
TSCPC (SC-TSCPC) as a reasonable primary option to lower IOP in eyes without prior 
incisional glaucoma surgery.(13, 14) 
There have been few reports of SC-TSCPC being used as a primary surgical treatment in 
patients with glaucoma,(15, 16) and few studies published in the literature documenting the 
effect of SC-TSCPC in patients with good VA.(17) 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

5 
 
Aim of the study 
 This study aims to evaluate and compare the safety and efficacy (IOP 
control) of SC-TSCPC versus trabeculectomy with MMC in the 
management of medically uncontrolled OAG in pseudophakic eyes. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

6 
 
Patients and methods 
 Study design: 
The current study is a prospective, comparative, interventional, randomized 
clinical study. 
 Study Population:  
Study participants:  
Will be 50 eyes of 50 patients with medically uncontrolled POAG, 25 
patients will be subjected to SC-TSCPC (group A), while the other 25 
patients will undergo trabeculectomy with MMC (group B). 
Randomization:  
Simple randomization will be done to get two equal groups. Cases will be 
randomly allocated to the groups through closed envelope system in which 
we will put 25 cards with symbol A and another 25 cards with symbol B in 
closed envelope. One card will be taken randomly and then will be allocated 
in the group according to the symbole in the card choosen. 
 Ethical approval: 
All patients included in this study will be verbally briefed about the details 
and the nature of the study & will sign a written consent according to the 
local Ethics Committee of Minia University Faculty of Medicine. 
 Place of the study:  
The study will be conducted in Ophthalmology department, Minia university 
Hospital, Egypt.  
 
 
 
 
 

7 
 
 Inclusion criteria: 
1. Patients above 40 years old with POAG who underwent previous 
uncomplicated cataract surgery with intraocular lens implantation. 
2. Pseudophakic patients with medically uncontrolled glaucoma in spite of the 
use of two anti-glaucoma medications or intolerance to medical therapy.  
3. Glaucoma patients with the following characteristics: 
 Visual field testing with defects in both the superior and 
inferior hemi-fields outside the central 5 degrees of fixation. 
 Mean deviation (MD) on standard automated perimetry (SAP) 
ranges between -6 dB and -12 dB. 
 
Exclusion criteria: 
1. Patients with history of previous glaucoma surgery.  
2. Patients who have used topical steroids within the last three months. 
3. Patients with significant media opacity, such as corneal opacity, that 
obstructs fundoscopic examination. 
4. Patients with ocular diseases as uveitis. 
5. Patients with severe ocular surface disorders as ocular cicatricial 
pemphigoid. 
6. Aphakic patients. 
7. Ocular interventions apart from YAG posterior capsulotomy. 
 Ophthalmic examination: 
All patients will be subjected to the following: 
(A)History: 
 Complete medical history 
 Family history of glaucoma. 

8 
 
 History of medications especially topical anti-glaucoma drugs (number of 
bottles, duration of treatment, & presence of any of side effects of these 
drops) also history of any systemic medications that may affect the IOP as 
systemic beta blockers for hypertension. 
 (B)pre-operative examination:  
All patients will undergo a comprehensive ocular examination including: 
 Uncorrected visual acuity (UCVA). 
 Best corrected visual acuity (BCVA) by log MAR scale. 
 Intraocular pressure by a calibrated Goldman-Applanation Tonometer.  
 Anterior segment examination using slit-lamp bio-microscopy. 
 Gonioscopic examination using Goldmann 3 mirror contact gonio lens. 
 Fundus biomicroscopy using a +78 D condensing lens for assessment of optic 
disc changes.  
 Measurement of central corneal thickness using Pentacam. 
 Optical coherence tomography of the macula (OCT macula). 
 Optical coherence tomography of the optic nerve head (OCT-ONH). 
 Visual field examination with Humphrey visual field analyzer. 
(C) Description of Surgical Procedure: 
         SC-TSCPC will be performed under local anaesthesia using topical 4% 
lidnocaine. All patients will receive 10 mg diazepam intramuscular half an hour 
before the procedure. A semiconductor diode laser system (wavelength 810 nm) 
will be used. A 600 μm-diameter laser delivery probe (G-probe) will be centered 
1.5 mm behind the surgical limbus and orientated parallel to the visual axis. 
         The technique will be standardized (energy: 1250 mW; duration: 4 seconds; 
24 applications). The applications will be divided into 2 arcs (upper and lower). 
For each arc, 12 spots will be applied over the ciliary body shadow sparing the 3 
and 9 o’clock meridians.  

9 
 
 
Following SC-TSCPC, prednisolone 1% eye drops four times a day, and 
ciprofloxacin 0.3% drops four times a day for the prophylaxis of conjunctival 
infection due to any possible clinical or subclinical conjunctival burn. 
Antiglaucoma medications will be tapered according to measured IOP. 
 
While trabeculectomy will be done according to Moorfields Safer Surgery 
System with MMC application with concentration 0.03.(18) 
 
(D) post-operative examination: 
1-IOP is measured by ICare tonometer. 
 The schedule of IOP measurement will be done 2 weeks, 1 month, 3 months 
and then 6 months. 
2-Postoperative assessment of the eye after the procedures: 
 Slit lamp examination: 
 To assess the anterior chamber as regarding its depth (whether 
normal or shallow & if there is any irido-corneal touch) & its content 
to exclude hyphemia or reaction. 
  Also, to assess the morphology of the bleb after trabeculectomy 
whether it diffuse, thin & avascular or not. 
 
3- Postoperative investigations: 
 OCT macula at 1 month post-operatively with comparing its parameters to 
their values pre-operatively to detect macular edema. 
 OCT-ONH after 6 months. 
 Visual field examination after 6 months. 
 
 

10 
 
 
 Statistical Analysis: 
 Data obtained will be compared for each group. 
 Results will be analysed using IBM SPSS. 
 P value < 0.05 will be considered significant. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

11 
 
 
References 
1. 
Mélik Parsadaniantz S, Réaux-le Goazigo A, Sapienza A, Habas C, Baudouin C. Glaucoma: 
a degenerative optic neuropathy related to neuroinflammation? Cells. 2020;9(3):535. 
2. 
Tham Y-C, Li X, Wong TY, Quigley HA, Aung T, Cheng C-Y. Global prevalence of glaucoma 
and projections of glaucoma burden through 2040: a systematic review and meta-analysis. 
Ophthalmology. 2014;121(11):2081-90. 
3. 
Zhang N, Wang J, Li Y, Jiang B. Prevalence of primary open angle glaucoma in the last 20 
years: a meta-analysis and systematic review. Scientific reports. 2021;11(1):13762. 
4. 
Weinreb RN, Aung T, Medeiros FA. The pathophysiology and treatment of glaucoma: a 
review. Jama. 2014;311(18):1901-11. 
5. 
Pantalon A, Feraru C, Tarcoveanu F, Chiselita D. Success of primary trabeculectomy in 
advanced open angle glaucoma. Clinical Ophthalmology. 2021:2219-29. 
6. 
Correia Barbosa R, Gonçalves R, Bastos R, Alves Pereira S, Basto R, Viana AR, et al. 
Trabeculectomy Vs Non‐penetrating Deep Sclerectomy for the Surgical Treatment of Open-
Angle Glaucoma: A Long-Term Report of 201 Eyes. Clinical Ophthalmology. 2023:1619-27. 
7. 
Takihara Y, Inatani M, Seto T, Iwao K, Iwao M, Inoue T, et al. Trabeculectomy with 
mitomycin for open-angle glaucoma in phakic vs pseudophakic eyes after phacoemulsification. 
Archives of Ophthalmology. 2011;129(2):152-7. 
8. 
Oh LJ, Wong E, Lam J, Clement CI. Comparison of bleb morphology between 
trabeculectomy and deep sclerectomy using a clinical grading scale and anterior segment 
optical coherence tomography. Clinical & Experimental Ophthalmology. 2017;45(7):701-7. 
9. 
Conlon R, Saheb H, Ahmed IIK. Glaucoma treatment trends: a review. Canadian Journal 
of Ophthalmology. 2017;52(1):114-24. 
10. 
Moussa K, Feinstein M, Pekmezci M, Lee JH, Bloomer M, Oldenburg C, et al. Histologic 
changes following continuous wave and micropulse transscleral cyclophotocoagulation: a 
randomized comparative study. Translational vision science & technology. 2020;9(5):22-. 
11. 
Duerr ER, Sayed MS, Moster SJ, Holley TD, Peiyao J, Vanner EA, et al. Transscleral diode 
laser cyclophotocoagulation: a comparison of slow coagulation and standard coagulation 
techniques. Ophthalmology Glaucoma. 2018;1(2):115-22. 
12. 
Khodeiry MM, Liu X, Lee RK. Clinical outcomes of slow-coagulation continuous-wave 
transscleral cyclophotocoagulation laser for treatment of glaucoma. Current opinion in 
ophthalmology. 2022;33(3):237-42. 
13. 
Sheheitli H, Persad PJ, Feuer WJ, Sayed MS, Lee RK. Treatment outcomes of primary 
transscleral cyclophotocoagulation. Ophthalmology Glaucoma. 2021;4(5):472-81. 
14. 
Quigley HA. The need for rigor in evaluating micropulse and other new procedures. 
Ophthalmology Glaucoma. 2020;3(3):171-3. 
15. 
Egbert PR, Fiadoyor S, Budenz DL, Dadzie P, Byrd S. Diode laser transscleral 
cyclophotocoagulation as a primary surgical treatment for primary open-angle glaucoma. 
Archives of Ophthalmology. 2001;119(3):345-50. 
16. 
Kramp K, Vick H-P, Guthoff R. Transscleral diode laser contact cyclophotocoagulation in 
the treatment of different glaucomas, also as primary surgery. Graefe’s Archive for Clinical and 
Experimental Ophthalmology. 2002;240:698-703. 

12 
 
17. 
Rotchford AP, Jayasawal R, Madhusudhan S, Ho S, King A, Vernon S. Transscleral diode 
laser cycloablation in patients with good vision. British Journal of Ophthalmology. 
2010;94(9):1180-3. 
18. 
Dhingra S, Khaw PT. The moorfields safer surgery system. Middle East African journal of 
ophthalmology. 2009;16(3):112-5. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

13 
 
 
 
 
الملخص العربي 
 
     
  الجلوكوما هو اعتالل العصب البصري الذي ٌتمٌز بالتدهور الهٌكلً والوظٌفً التدرٌجً للعصب البصري . إنه أحد األسباب
.الرئٌسٌة للعمً الغٌر قابل للعالج فً جمٌع أنحاء العالم  
       
 الجلوكوما ذات الزاوٌة المفتوحة هً النوع الفرعً األكثر شٌوعًا من الجلوكوما. وقدر عدد األشخاص الذٌن تم تشخٌص إصابتهم
 بالجلوكوما ذات الزاوٌة المفتوحة بنحو86.25
 
 ملٌونًا فً عام6262
 ومن الم توقع أن ٌصل إلى97.92
 
 ملٌونًا فً عام6202
.
 
        
 فً الجلوكوما ذات الزاوٌة المفتوحة ، ٌظل الحفاظ على الرؤٌة هو هدف العالج من خالل تصحٌح عامل الخطر الوحٌد القابل
للعالج فً الجلوكوما وهو ضغط العٌن. ٌمكن تحقٌق ذلك من خالل طرق مختلفة بما فً ذلك الطرق الطبٌة أ
و اللٌزر أو الجراحٌة.
  
ف فً كثٌر من الحاالت، ٌمكن أن توفر العالجات الطبٌة واللٌزر تحكمًا فعاالً فً ضغط العٌن، بٌنما ال تزال الجراحة ضرورٌة عندما
تفشل 
ًاالول 
 فً خفض ضغط العٌن بشكل كافٍ، أو إذا لم ٌكن المرٌض
ملتزما ب
تلك الطرق العالجٌة  
        إ ن
استئصال التر
بٌق مع اضافة مادة ال 
 مٌتومٌسٌن هو إجراء ترشٌح ٌقلل من ضغط العٌن عن طرٌق إنشاء اتصال بٌن الغرفة
 ،األمامٌة والحٌز تحت الملتحمة بعد استئصال جزء من الشبكة التربٌقٌة. لسوء الحظ، على الرغم من أنه ٌقلل من ضغط العٌن بشكل فعال
إال أنه ٌرتبط بارتفاع معدل حدوث المضاع فات مثل انخفاض
ضغط العٌن ، أو فقدان الغرفة األمامٌة أو
االرتشاح فوق المشٌمٌة.
  
        
 إن العالج باللٌزر كإجراء مدمر ٌخفض ضغط العٌن عن طرٌق تقلٌل إنتاج السائل المائً حٌث ٌتم إمتصاص اللٌزر
 ًالمطبق علً الصلبة بواسطة صبغة المٌالنٌن فً الجسم الهدبً مما ٌؤدي إل تخثر الجسم الهدبً وكان ٌعتبر ذات ٌوم هو
  .الخٌار األخٌر فً العٌون ذات اإلمكانٌات البصرٌة المنخفضة للغاٌة بسبب المخاطر المرتبطة بشدة اإللتهاب وضمور العٌن
        االن ومع التطورات األخٌرة فً إعدادات اللٌزر تحسنت سالمة تدمٌر الجسم الهدبً عبر الصلبة مما ٌجعله 
 خٌارا غٌر
 جراحً قابل للتطبٌق لمجموعة أوسع من المرضً بما فً ذلك مرضً الزاوٌة المفتوحة مع وجود عدسة إصطناعٌة داخل
.العٌن 
         
 "تستخدم طرٌقتان بشكل شائع لتوصٌل طاقة اللٌزر بإستخدام التخثر الضوئً المستمر عبر الصلبة: تقنٌة "الفرقعة
 التقلٌدٌة حٌث ٌتم زٌادة طاقة اللٌزر حتً ٌتم سماع فرقعة مشتقة من األنسجة ثم ٌتم تقلٌل الطاقة حتً ال ٌتم سماعها بعد. لذا
 ًبدءا بقوة طاقة اللٌزر حوال0982
-
6222
 
 مللً واط لفترة زمنٌة قصٌرة6 
 ثانٌة.علً النقٌض من ذلك ٌستخدم التخثر
الضوئً البطئ  والذي ٌستخدم كمٌة أقل من الطاقة علً مدي فت ًرة ممتدة حوال0682
 
 مللً واط علً مدي0 
.ثوان 
         
 أظهرت النتائج الحدٌثة التً قارنت بٌن نتائج نهج التخثر البطئ والنهج التقلٌدي انخفاض معدل حدوث المضاعفات
 بعد الجراحة فً مجموعة التخثر البطئ. التخثر التقلٌدي كان ٌستخدم سابقا فً العٌون المؤلمة العمٌاء والعٌون التً فشلت فٌها
جراحات الجلوكوما السابقة إ ًال أن التخثر البطئ أصبح خٌار معقول لخفض ضغط العٌن دون اللجوء إلً الجراحة ف
.المرضً الذٌن لدٌهم حدة إبصار جٌدة