|Year : 1988 | Volume
| Issue : 4 | Page : 158-161
A prospective comparison between trabeculectomy, Scheie's sclerostomy under scleral flap operation and thermal (Sub Scleral Scheie's) procedure
Jagmeet Kaur, Gurdeep Singh
E-1/100, Arera Colony, Bhopal - 462 016, India
E-1/100, Arera Colony, Bhopal - 462 016
Source of Support: None, Conflict of Interest: None
A comparative study of trabeculectomy, Scheie's operation and Sub Scleral Scheie's operation (Thermal Sclerostomy under Scleral flap) is presented in this study. Results on thirty eyes divided into three groups of 10 each were evaluated. It was observed that Scheie's operation was the easiest to perform while trabeculectomy required more precision and better magnification for the proper dissection of trabecular tissue while Sub-Scleral' Scheie's operation was a relatively easier procedure. There was early formation of anterior chamber post operatively in trabeculectomy and Sub-Scleral Scheie's procedure, and relatively delayed formation in classical Scheis's operation.
The type of blebs following trabeculectomy and Sub-Scleral Scheie's procedure were diffuse and thick (Type 1 and II1 while those after Scheie's operation were comparatively large and cystic (Type III). These are not only cosmetically less satisfactory but also have the potential risk of perforation and late infection
Intra ocular pressure was controlled with all procedures. However the incidence of hypotony was least after trabeculectomy and maximum after Scheie's operation. It was mid-way in the group of cases operated by Sub-Scleral Scheie's procedure.
Modified Scheic's procedure under a scleral flap thus combines the advantages of Trabeculectomy with the ease of performance of Scheie's operation and thus could be taken up as a valuable alternative procedure in the choice of glaucoma surgery. This study in no way provides a full answer to which surgical procedure is ideal but it will definitely help a surgeon to decide which procedure is more appropriate for a particular case.
|How to cite this article:|
Kaur J, Singh G. A prospective comparison between trabeculectomy, Scheie's sclerostomy under scleral flap operation and thermal (Sub Scleral Scheie's) procedure. Indian J Ophthalmol 1988;36:158-61
|How to cite this URL:|
Kaur J, Singh G. A prospective comparison between trabeculectomy, Scheie's sclerostomy under scleral flap operation and thermal (Sub Scleral Scheie's) procedure. Indian J Ophthalmol [serial online] 1988 [cited 2020 Apr 1];36:158-61. Available from: http://www.ijo.in/text.asp?1988/36/4/158/26121
| Introduction|| |
Despite the introduction of effective medications, there are certain problems like lack of effective response to drugs like miotics and betablockers, non compliance to medical therapy in some people and lack of follow up of cases especially in rural areas. These problems lead us to early surgical management especially in cases where sufficient medical therapy has already been given.
The fact that during the last few decades a large number of operations have been designed for the relief of glaucoma, suggests that we have not yet found an ideal surgical procedure.
In this study we have tried to evaluate and compare three operations i.e. Trabeculectomy, Scheie's procedure and Thermal sclerostomy under a scleral flap.
The evaluation was based on
1. Ease of performance/problems during surgery.
2. Reliable and permanent effect in maintaining the IOP within safe limits.
3. Lack of immediate and late complication like shallow anterior chamber hyphaema and lenticular
4. Nature of bleb and cosmetic satisfaction
5. Preservation of good surgical field for possible future operation.
| Material and Methods|| |
This study covers 29 cases (30 eyes) mostly comprising of primary glaucoma with open and narrow angles. There was one case each of secondary and juvenile glaucoma. The cases were divided at random into three groups of ten each. Each group was managed with one of the three surgical procedures and followed up for approximately two years. All the surgeries were performed by the same surgeon. Pre-operative examination included a thorough external ocular examination with slit lamp, Goldmann applanation tonometery, gonioscopy, fundus examination and Goldmann perimetry, if possible.
The indications for surgery were progressive visual field loss with progressive cupping, failure of medical therapy or when the surgeon felt that the patient would not follow the medical regime properly.
The surgical technique for trabeculectomy and Scheie's operations were as described by Cairns' and Scheie's  respectively. In the third group of patients where the Sub-Scleral Scheie's operation was adopted the detailed procedure was as follows:
A limbal based conjunctival flap with one half thickness scleral flap of 5 mm x 4 mm was prepared. 1 mm away from the limbus and under the scleral flap a 2.5 mm - 3 mm wide incision was made on the sclera. Both the lips of the incised sclera were cauterised, the posterior lip more than the anterior. The anterior chamber was then perforated with a blade and a peripheral iridectomy was done. The scleral flap was sutured with four 8-0 virgin silk sutures and the conjunctival flap with 6-0 continuous chromic catgut sutures. In all the procedures the anterior chamber was reformed with balanced salt solution and the eyes were dressed with 1% Altropine and Chloromycetin applicaps.
Post-operative care was essentially the same for all the eyes and consisted of topical 0.1% Dexamethesone four times a day, 1 % Altropine BD and antibiotic drop also given 4-5 times a day.
The patient was on an average kept in the hospital for about 10 days and a record of post operative tension, examination of the anterior and posterior segment of the eye and visual acuity etc. was maintained.
The first follow up was usually done after one week and then monthly follow up was done in all the cases and particular attention was paid to the visual recovery, condition of the anterior chamber, intra ocular pressure and nature of the filtering blebs.
| Results|| |
The comparative results of the three procedures are summarised in [Table - 1][Table - 2][Table - 3][Table - 4][Table - 5][Table - 6][Table7].
The maximum number of cases had an interaocular pressure between 40.1 to 50 mm Hg. i.e. 9 patient, of which 3 each were subjected to Scheie's, Trabeculectomy and Theremal Sclerostomy under scleral flap.
| Discussion|| |
A large number of surgical procedures which have been introduced for the control of raised tension in glaucoma, is testimony to the fact that the ideal operation which should preserve eye functions, maintain the TOP within normal limits and retain the integrity of the globe has not yet been developed.
Various surgeons have advocated many types of surgical procedure and there are numerous comparative studies between various procedures.
(A) Intra Ocular Pressure
S.M. Drance and C. Vargas  while comparing Scheie's operation with trabeculectomy found no significant difference in the control of IOP by the two procedures.
Spaeth et a1  noted that the IOP, 3 years after Scheie's operation in patients with primary open angle glaucoma was 12.3±6 in comparision with 16.6±7 mm Hg, treated with trabeculectomy.
In our series of 30 eyes (ref [Table - 5]) the IOP was controlled in all the cases except one in which it was 24.4 mm Hg. This case was operated by trabeculectomy.
Excessive filteration (hypotony) was observed in two cases and both the cases were operated by Scheie's procedure. The over all best control was observed in the group operated by Sub-Scleral Scheie's procedure.
(B) Depth of the Anterior Chamber
Delayed formation of the anterior chamber has been a known complication of Scheie's operation. G.L. Speath  in a series of 15 cases found that the incidence of flat anterior chamber was much higher in the group of cases operated by Scheie's procedure than those operated by trabeculectomy.
Rollins David  in a series of 48 eyes operated by trabeculectomy showed that shallow anterier chambers were observed in 8.5% of the cases.
In our series also the incidence of shallow anterior chamber on the first post-operative day in the group of cases operated by Scheie's procedure coincides with those of Spaeth et al.
The maximum number of cases (80%) showed formed anterior chamber on first post-operative day after trabeculectomy. It was formed by the 7th day in all cases except one (10%) which was operated by Scheie's procedure. Air injection was done to reform it. (Ref. [Table - 6]).
(C) Nature and Type of Filtering Blebs
Filtering surgery in glaucoma is aimed at obtaining a diffuse and permanent filteration cicatrix with a regulated intra ocular pressure. Sometimes large cystic blebs are formed after these surgeries which may cause visual disturbances, foreign body sensation and which carry a grave risk of infection.
Pierre Blondeau and C.D. Phelps  in their series of cases found more raised, thin and cystic blebs with late infection in cases operated by Scheie's procedure as compared to those in which trabeculectomy was done.
Thyer and Wilson  in their preliminary study noted bleb formation in 72% cases operated by trabeculectomy.
In the present study depending on the nature of the bleb we classified them into three types.
Type - I Bleb extremely small and diffuse
Type - II Bleb medium sized, thick and diffuse Type - III Bleb large raised and cystic.
Reference [Table - 5], we found that Type III bleb were seen in 20% of the eyes and all these cases were operated by Seheie's technique. Type II blebs were seen in most of the eyes (70%) while type I blebs were seen in 10% of the cases (3 eyes), two of which were operated by trabeculectomy and one by sub scleral scheie's procedure.
(D) Visual Acuity and Lenticular Changes Reference [Table - 6][Table - 7].
In our series visual acuity remained the same in 90% of the eyes operated by Scheie's operation while in 10% it deteriorated.
In the group of cases where trabeculectomy was done there was improvement in both the eyes of a case of juvenile glaucoma, while in the third grop also one eye showed improvement in visual acuity. In all these cases the improvement was due to clearing of corneal oedema.
Drance and Vargas  found a reduction in the visual acuity in 30% of the eyes operated by Scheie's procedure and 11% in those operated by trabeculectomy. Lorraine JB et al  in their series found that the visual acuity post operatively was unchanged or decreased in 56% of cases and showed improvement in 29% cases after Sub Scleral Scheie's procedures.
Post operative lenticular opacification has been studied extensively after filtering surgeries by H.B. Sugar  and various mechanisms have been blamed for this complication.
In our series, only in one case was an increase in the lenticular opacity observed. This case showed a consistently shallow Anterior chamber and air injection had to be done on the 7th post operative day. This secondary procedure could have been a cause of increased lenticular opacity in this case.
In the present study, the least amount of complications were seen in the group of cases where thermal sclerostomy under a scleral flap was employed as the filtering procedure.
| References|| |
Cairns JE: Trabeculectomy, preliminary of a new method. Amer. J. Ophthal. 66: 673-679, 1968.
Scheie HS. Retraction of scleral wound edges as a fistulising procedure for glaucoma. Amer. J. Ophthal. 45: 220, 1958.
Drance SM, Vargas E. Trabeculectomy and thermosclerostomy. A comparision of two procedures. Can. J. Ophthal. 8: 413-5, 1973.
Spaeth G.L. et al: Trabeculectomy, a re-evaluation after 3 years and a comparision with Scheie's procedure. Trans Am. Acad. ophthalotolaryngol. 79: 349-61, 1975.
Spaeth G.L. and Effie Poryzees: A comparision between peripheral iridectomy with thermal sclerostomy and tral-eculectomy A controlled study. Brit. J. Ophthal-65:.783-89, 1981.
Rollins D.E. and Drance SM. Symposium on glaucoma transactions of the New Orleans Academy of Ophthalmology, 295. The C V Mosby company, London. 1981.
Pierre Blondeau and C.D.Phelps. Trabeculectomy Vs Thermosclerostomy: Randomized Prospective clinical Trial. Arch. Ophthal. 99: 810-816, 1981.
Thyer HW and Wilson P. Brit.J.Ophthal. 56: 37, 1972.
Lorraine J.B. et al. Role of Sub Scleral Scheie's procedure in glaucoma surgery: Ophthalmic surgery Dec. Vol.17, No. 121986.
Sugar H.S. Post operative cataract in successfully filtering glaucomatous eyes. Amer.J.Opfithal 69: 740-6, 1970.
[Table - 1], [Table - 2], [Table - 3], [Table - 4], [Table - 5], [Table - 6], [Table - 7]