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ARTICLES |
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Year : 1981 | Volume
: 29
| Issue : 3 | Page : 157-160 |
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Transciliary filtration for intractable glaucoma
Daljit Singh, Arun Verma, Mohindar Singh
Department of Ophthalmology, Medical College, Amritsar, India
Correspondence Address: Daljit Singh Department of Ophthalmology, Medical College, Amritsar India
Source of Support: None, Conflict of Interest: None | Check |
PMID: 7346420
How to cite this article: Singh D, Verma A, Singh M. Transciliary filtration for intractable glaucoma. Indian J Ophthalmol 1981;29:157-60 |
A new non-conventional filtration procedure "Transciliary Filtration" has been devised by us and utilized in cases of far advanced glaucoma or absolute glaucoma and other cases in which conventional surgery had failed or was most likely to fail.
Materials and methods | | |
A total of 27 cases have been treated by this method so far, out of which 12 cases were males and 15 females.
Their ages ranged between 30 to 70 years, the majority (55.5%) of them being in the age group of 51 to 60.
Out of these 27 cases, 9 (33.3%) cases were aphakic. 8 (29.6%) cases had under gone repeated surgery for glaucoma and were still uncontrolled.
Clinical Findings
The anterior chamber was absent in 6 (22.2%) cases, shallow in 13 (48.1%) cases and normal in 1 (3.8%) case. The anterior segment was completely disorganized in 7 (35.9%) cases with vitreous touching the back of cornea. The iris pattern was normal in 5 (18.5%) cases only. Iris atrophy was present in 22 (81.5%) cases. Extensive synechiae were seen in 12 (44.4%) cases. The pupil was dilated and fixed in 19 (70.3%) cases. 2 (7.4%) cases had complete pupillary membranes. 6 (22.3%) cases had sluggishly reacting pupil. The lens was normal in 2 (7.4%) cases, cataractous in 16 (59.2%) cases and absent (aphakic) in 9 (33.3%) cases. Except in one case of aphakic glaucoma, fundus was not visible in any case. In all cases the tension was more than 40 mm Hg. Schiotz. The present study was conducted only in those cases who had little or no vision. [Table - 1] shows the various types of glaucomas.
Operative technique : Pre-operatice management : The intraocular pressure is controlled with medical means. Antibiotic and steroid drops are instilled frequently.
Steps of Operation
- An 8 to 10 mm conjunctival flap is fashioned towards but not upto the limbus.
- With the help of a razor blade, a half thickness triangular scleral flap, each side about 4-5 mm long, with the base towards and about 3½-4 mm away from the limbus is fashioned. While making the scleral flap, the anterior ciliary vessels are avoided [Figure - 1].
- A 1 to 1½ mm square opening is made in the deeper layers of the sclera, near the base of the flap and the ciliary body exposed in the area of pars plana [Figure - 2].
- The exposed uveal tissue is cauterized with a hot probe [Figure - 3].
- A small nick is given in the cauterized uveal tissue till a small ooze of aqueous is seen. A square piece of uveal tissue is removed with forceps and scissors. If vitrectomy is desired then after the exposed uveal tissue is removed the vitreous is made to bulge out by pressure.
- The scleral flap is stitched back to its original place by a stich at the apex of the riangle.
- The conjunctival flap is sutured.
At the end of operation, subconjunctival injection of 2 mgm dexamethasone is given, antibiotic ointment instilled and the eye bandaged.
The patients are generally discharged on the 4-5th day. They are prescribed local steroid drops for about one month.
Observations | | |
Operative Complications : There was no significant operative complication. Intentional vitrectomy was done in 8 (29.6%) cases, unintentional vitrectomy was done in 4 (14.8%) cases and no vitrectomy in 15 (55.6%) cases.
Post-Operative Complicatians : No post-operative complication was encountered in any of the cases. All patients experienced dramatic relief of pain within the first 24 hours, which did not reccur.
Follow Up: The patients have been followed from 3 to 9 months. The control of intra ocular pressure was adequate [Table - 2][Table - 3].
Out of the three patients with good vision, one had lens-induced glaucoma and her cataract was removed one month later. The other two cases suffered from aphakic glaucoma.
Discussion | | |
Routine filtration operations are likely to fail in great majority of advanced glaucoma cases because there is considerable damage to the anterior segment. The operation of "Transciliary Filtration" employs an opening in the posterior segment in the region of the pars plana. The choice of this site is based on the following considerations
Anatomic and physiologic considerations The pars plana of the ciliary body is the least vascularized part of the uveal tract. It is unrelated the angle of the anterior chamber and is also away from the lens. It is very close to the site of formation of the aqueous. An opening in this region provides almost direct passage outwards. There is no risk of uveal tissue prolapse, because the ciliary body is fixed all around. The use of mydriatics or cycloplegics is quite in order. Surgery through this area causes little or no bleeding. The sclera over it is also far less vascular. The total amount of aqueous in a normal eye is about 330 cμl., out of which only 80 cμl. is present in the posterior chamber. This quantity may be increased considerably in many cases of glaucoma, especially when there is angle closure with shallow or absent anterior chamber. It should be remembered that the aqueous is formed at the rate of 2 cμl. per minute. A 12 micron patent channel can drain away this amount of fluid and keep the pressure normal, provided the fluid is absorbed by the subconjunctival tissues.
Filtration in the pars plana area does not cause loss of anterior chamber, nor does it effect the integrity of the existing channels of drainage. On the other hand it has a tendency to deepen the the anterior chamber by reducing the pressure in the posterior chamber, as was observed by us in a few cases.
Pathologic considerations : surgery through this relatively avascular area causes little or no inflammatory reaction. Buettner[2] studied the formation of proliferative tissue in the region of pars plans after operation. Fibrovascular ingrowths along the sclerotomy site in this region was always limited. These slight proliferative changes appeared to originate from the subepithelial layer of pars plana and sclera (both relatively avascular structures). He also studied cases of vitrectomy and lensectomy through pars plana and concluded that surgery at this site did not contribute to any intraocular inflammation. The complete absence of inflammatory reaction in all our cases confirms these observations.
Clinical considerations : The relief of pain is dramatic and lasting even in those cases where the tension remained elevated.
We all are faced sometimes with the problem of an eye with advanced glaucoma which still has some useful vision left, but due to the complicated nature of glaucoma (usually aphakic) or due to previous surgical failure, we have to finally choose an operation which should give him relief from pain. In the present study, two aphakic patients and one lens induced glaucoma case had intense pain and the vision was finger counting. After operation, the pain disappeared and the final corrected vision improved remarkably in all of them.
In the present study, no case was given any anti-glaucoma medication in the post-operative period, even in those who had elevated tension after operation.
Subjective relief of pain, disappearance of ciliary congestion, improvement of corneal oedema and lowering of intraocular pressure are all reasonably convincing data that "Transciliary Filtration" works satisfactorily as an antiglaucoma operation, at least for types of cases discussed.
It is however too early to show undue enthusiasm about the results and the utility of the procedure as a routine in glaucoma cases.
References | | |
1. | Watson, P.G., 1977, Controversy in Ophthalmology ; Pg. 190, W.B. Saunders Company, Philadelphia. |
2. | Buettner, H., 1977. Arch. Ophthalmol. 95 : 2031 |
[Figure - 1], [Figure - 2], [Figure - 3]
[Table - 1], [Table - 2], [Table - 3]
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