Year : 1990 | Volume
: 38 | Issue : 4 | Page : 150-
Lasers in glaucoma II
Dr. Rajendra Prasad Centre for Ophthalmic Sciences, A. I. I.M.S., New Delhi 1100029, India
N N Sood
Dr. Rajendra Prasad Centre for Ophthalmic Sciences, A. I. I.M.S., New Delhi 1100029
|How to cite this article:
Sood N N. Lasers in glaucoma II.Indian J Ophthalmol 1990;38:150-150
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Sood N N. Lasers in glaucoma II. Indian J Ophthalmol [serial online] 1990 [cited 2024 Feb 27 ];38:150-150
Available from: https://journals.lww.com/ijo/pages/default.aspx/text.asp?1990/38/4/150/24516
The use of lasers is slowly pervading all subspecialities of Ophthalmology, especially glaucoma. The ad�vantages of a noninvasive technique over surgery are obvious, but unfortunately the worldwide follow up of laser procedures is relatively short, as compared to established surgical methodologies. The varying effec�tivity and the modifications required in different racial groups and subgroups are now coming to the fore. The need of the hour for us today, is a collation of Indian data regarding laser parameters, effectivity, duration of ac�tion and complications encountered, to give us a clearer picture of these procedures in Indian eyes.
In a recent survey on the usage of lasers in India, our respondents informed us that almost 50% of them were using lasers in the therapy of glaucoma, but mostly for iridotomies. A few centers were practicing argon laser tabeculoplasties but only a couple were using the tech�niques of gonioplasty, cyclophotocoagulation, photosclerostomy etc. The lenses most commonly used were the Abraham/Wise, and the special c..drtz lenses with the YAG laser.
Laser iridotomies are of proven value in angle closure glaucoma i.e. in fellow eyes, subacute and acute eyes. In chronic angle closure glaucoma the effectivity is limited by the extent of trabecular damage that has already occurred. YAG laser iridotomies seem to be easier to perform and maintain their patency better in Indian eyes. We would also recommend the more fre�quent use of argon laser trabeculoplasty, gonioplasty, photosclerostomy and suturotomies in the management of patients having glaucoma. For these techniques no special equipment or elaborate technique is required and the Goldmann 3 mirror lens or Zeiss 4 mirror can be successfully used.
Argon laser trabeculoplasty in patients with open angle glaucoma can be used to postpone or pre-empt surgery for systemic, socioeconomic or other reasons. Very few patients develop a post laser rise in intraocular pressure, following a 180� anterior trabeculoplasty, and the effec�tivity ranges between 60-65% at the end of 1 year. Close follow up is however mandatory as 10% of eyes continue to fail per year.
Gonioplasty has been found to be of significant use in patients with nanophthalmos, plateau iris syndrome, unresolved acute attacks etc. and is also effective in patients with angle closure glaucoma having peripheral anterior synechiae of less than 180� including a third of patients with documented chronic angle closure glaucoma. Reapplication of laser burns may be re�quired in 3-6 months.
Photosclerostomy in patients with failed filtering surgeries has been shown to be very effective, especial�ly within first 6-8 weeks following surgery. This may be done, with conventionally available argon/YAG lasers depending on the pigmentation of the tissue blocking the sclerotomy. Cyclophotocoagulation of at least 180� is required in Indian eyes and the end point of therapy is pitting, with minimal blanching, as compared to just pitting in caucasian eyes. Vitreolysis has been found to be the therapy of choice in malignant glaucoma.
The complication rate following trrabeculectomies is low, but in this age of perfection, the drive is on to reduce this to an unavoidable minimum. The occurrence of shallow/ flat anterior chambers postoperatively can now be done away with, by applying more 8/0 or 10/0 monofilament nylon sutures to the scleral flap, maintain�ing the anterior chamber in the early postoperative phase and by using the argon laser to do a titrated suturotomy depending on the patients intraocular pres�sure and depth of the anterior chamber, in the pos�toperative period.
Lasers are slowly replacing many glaucoma surgeries. In open angle glaucoma today, primary medical therapy followed by argon laser therapy is the management of choice. In angle closure glaucoma, surgical iridectomies are passing into the annals of history and gonioplasty with or without trabeculoplasty, is aiming to treat even those patients who would have equired a trabeculec�tomy. Further innovations in, laser technology envisag�ing the use of lasers to perform primary sclerotomies and goniotomies either by the ab externo approach .with excimer lasers or the ab intergo approach with the use of endolaser probes. Surgery is slowly being relegated by this tide of newer laser techniques to the status of last ditch procedure.
We must ensure that we stay ahead of this new wave and provide our patients the best laser care, suited to Indian eyes.