|Year : 1988 | Volume
| Issue : 2 | Page : 63
The impact of lasers on glaucoma management
NN Sood, Ramanjit Sihota
R P. Centre for Ophthalmic Sciences, AI.I.M.S. Ansari Nagar, New Delhi-110029, India
N N Sood
R P. Centre for Ophthalmic Sciences, AI.I.M.S. Ansari Nagar, New Delhi-110029
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Sood N N, Sihota R. The impact of lasers on glaucoma management. Indian J Ophthalmol 1988;36:63
The advent of lasers has opened exciting and alternative possibilities- in the management of glaucoma. ,, The lack of availability of adequate number of machines in the country as also the pre occupation with treatment of posterior segment disorders perhaps delayed its use for glaucoma Another factor that soon came to light was the inadequate response of Argon lasers for iridotomy in cases of angle closure glaucoma. , It is a well known fact that angle closure glaucoma is as frequent as open angle glaucoma, tends to occur in younger individuals and is related to the shallower AC. depth in Indians.  With the availability of Yag lasers in the country the non invasive approach for A.C.G. has been revolutionised. Argon laser iridotomy is more difficult and more often associated with closures due to proliferation of pigment epithelium in dark brown iridis of Indian eyes. Nd Yag laser causes disruption of tissue and the opening in the pigment epithelial layer is larger than the stromal, assuring a long term patency is almost all eyes. Nd. Yag (mode locked) iridotomies require a power of 3-5 mJ in Indian eyes and 85% of patients need only one sitting and 15% need two sittings.  Microhyphaemas are a common feature, especially with Q switched Nd Yag lasers and need pretreatment with-Argon laser. Care is needed in carrying out the iridotomies in extremely shallow AC's in the peripheral area, as temporary dysfunction of the corneal endothelium may occur. This non- invasive approach is attractive both to the ophthalmologists and the patients, being an out patient procedure, the risk of complications being less as compared to surgical iridotomy. , Laser iridotomy is effective and safe. Until such time that more institutions are equipped with lasers both surgical and laser iridectomies would continue. However, in certain situations it would be preferable to refer cases to centres for laser iridotomy viz one eyed cases needing iridectomy, other eye having developed malignant glaucoma and cases of nanophthairnos.
Argon laser trabeculoplasty on the other hand may only postpone the surgery or decrease the medications for those on maximal medical therapy in cases of OAG. , ALT is currently also being evaluated as a primary therapy for cases of OAG. It needs to be appreciated that these patients with OAG who are not suitable for medical treatment should not be subjected to ALT as drug therapy may need to be continued after ALT.
Another laser procedure that is reasonably established is Laser iridoplasty (gonioplasty) for cases of plateau iris, nanophthalmos and case of OAG with narrow entry to enable A LL f. to be carried out.
Iris and Goniophotocoagulation with/ without prior retinal photocoagulation is helpful in cases of neovascular glaucoma. Photocoagulation of ciliary process by Argon laser may be especially useful in cases of aphakic malignant glaucoma
Lasers now form a basic element of current glaucoma care and the liberalization of import of laser equipment by the Government of India is a welcome step. A reorientation of gonioscopy and a more efficient utilization of laser machines already available in the country is called for. Carbon-dioxide lasers and tunable dye lasers are adding new dimensions to management strategies. Will these replace the surgeon s knife ? Such possibilities are on the horizon.
ACG - Angle Closure Glaucoma OAG - Open Angle Glaucoma
ALT - Argon Laser Trabeculoplasty AC - Anterior Chamber
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