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GlaucomaLONG TERM EFFECT OF APRACLONIDINE Araujo SV. Bond JB. Wilson RP. Moster MR. Schmidt CM. Spaeth GL. British Journal of Ophthalmology. 79(12):1098-1101, 1995 Dec. Aims To evaluate the effect of the chronic use of apraclonidine 0.5% on the intraocular pressure (IOP) of patients with glaucoma; also, to study the side effect profile of this drug when used chronically. Methods All patients who had uncontrolled IOP, who were either already on glaucoma medications, or who were intolerant of other glaucoma medications were enrolled. A total of 185 patients were started on apraclonidine 0.5% two to three times a day in one eye. Results Follow up extended to 35 weeks. The mean difference in IOP between treated and control eyes was 2.1 (SD 5.0) mm Hg. A similar IOP lowering effect was obtained comparing IOP difference from baseline in the treated eye only. Conclusion By the end of the follow up period, 46% of patients were still on the medication. The drug was stopped in 23% of patients because of side effects and in 31% of patients because of failure to lower IOP significantly.
GlaucomaComparison of Latanoprost and Timolol in Patients with Ocular Hypertension and Glaucoma: A Six-month, Masked, Multicenter Trial in the United States Camras, C., the U.S. Latanoprost Study Group Ophthalmology, 1996;103:138-147 Prostaglandins are a class of molecules that have been around for some years. In the past decade, synthetic analogues have been tested for biological effect. PG F2alpha is an interesting compound with a myriad of effects. Perhaps its most studied property is its effect on uterine muscle during childbirth, promoting intense contractions. An analogue has been tested in the eye and found to decrease intraocular pressure. Pilot studies showed it lowered intraocular pressure in humans. These were short duration studies involving small sample sizes. This paper looks at a larger sample size followed over a six month period comparing the pressure lowering effect of once daily 0.005% Latanoprost to Timolol 0.5% given twice daily. 268 patients were enrolled. Criteria for inclusion were stringent. Some of these criteria were the presence of ocular hypertension (OHT), primary open angle glaucoma (POAG), exfoliation syndrome (PXE) or pigment dispersion syndrome (PDS) in at least one eye. Exclusion criteria of note: currently pregnant or breast feeding; concurrent use of a non-glaucoma eye mediciation; narrow angles or synechiae on gonioscopy; less than 6 months status post glaucoma surgery (,aser or otherwise); recent ocular inflammation; known allergy or contraindication for either drug; history of non-compliance; and medically unstable. All patients enrolled were judged by the examiners to be stable enough to participate in the study for the full duration. Selection was limited further to patients with an IOP greater than 21 on a maximum of one glaucoma mediciation. No person with rapid visual loss or severely elevated pressure was selected. Methods:Current glaucoma medication (if any) was terminated a reasonable period of time was allowed to lapse prior to randomization. 140 of the subjects were given Timolol 0.5% every twelve hours. 128 were given 0.005% Latanoprost at night and twelve hours later, the vehicle alone, without medication was given. Each patient was given two bottles to ensure they were masked as to which treatment arm they were part of. Follow-up examinations were performed at 2 weeks, 6 weeks, and at the 3, 4 5 and 6 month intervals.Results:10 subjects were dropped from each arm. Latanoprost had 2 patients with allergic blepharitis, as did the Timolol arm. 4 (3%) Latanoprost patients were withdrawn for palpitations (1), ulcer symptoms (1) and maculopapular rash (2). 3 Timolol subject were withdrawn palpitations, shortness of breath (and ensuing bypass surgery) and one status post mastectomy for breast cancer. 4 Timolol patients were withdrawn because thier pressures were inadequately controlled. No outright treatment failures were noted in the Latanoprost group.Effect on intraocular pressure: 6 months Latanoprost - 6.7+/- 3.4 mmHg (27%) Timolol 4.9+/- 2.9 mmHg (20%) No significant difference in ocular symptoms/complaints were noted between the two medications. This is the third paper to clearly show 0.005% Latanoprost given once daily is more effective than Timolol 0.5% given twice daily over a six month period. It may become the first line therapy for the treatment of glaucoma.
GlaucomaIncomplete Elimination of Exercise-Induced Pigment Dispersion by Laser Iridotomy in Pigment DispersionSyndrome William L. Haynes, M.D., Wallace L.M. Alward, M.D., Celso Tello, M.D., Jeffrey M. Liebmann, M.D., Robert Ritch, M.D. Ophthalmic Surg, 1995;26:484-486 A 33-year old man with PDS and a marked peripheral iris concavity had bilaterally symmetric, marked pigment dispersion into the anterior chamber accompanied by IOP elevation into the mid 30s in both eyes after playing basketball. The pigment dispersion and pressure rise were inhibited by pretreatment with 0.5% pilocarpine but not by 0.5% thymoxamine. 4 The peripheral iris concavity was also reversed by 0.5% pilocarpine, but not by 0.5% thymoxamine. Laser iridotomy OD eliminated the concave iris configuration in the untreated state. Exercise testing was repeated several weeks later. Prior to exercise, IOP was 18 mmHg OD and 19 mmHg OS, and there was no detectable pigment in the anterior chamber in either eye. Thirty minutes after playing basketball for two hours, anterior chamber pigment was 2+ OD and 4+ OS and IOP was 21 mmHg OD and 36 mmHg OS. Two weeks later he underwent exercise testing after pretreatment with one drop of 0.5% pilocarpine OU. Prior to exercise, IOP was 17 mmHg OD and 19 mmHg OS, and there was no detectable anterior chamber pigment in either eye. Thirty minutes after exercise, there was still no detectable anterior chamber pigment in either eye and IOP was 15 mmHg OD and 17 mmHg OS. Gonioscopy revealed a flat iris contour OD, while that OS was slightly convex. Ultrasound biomicroscopy (UBM) was performed OU before and after treatment with pilocarpine. The iris configuration OD was planar both before and after pilocarpine. The peripheral iris OS was concave prior to pilocarpine and became convex after treatment. Some patients with PDS have a burst of pigment liberation into the anterior chamber accompanied by a sudden rise in IOP after pharmacologic pupillary dilation or after exercise. 2, 4, 5, 9, 11 Pretreatment with pilocarpine before exercise can prevent this phenomenon, presumably by elimination of iridozonular contact. 4 Miotics not only lower IOP, but produce relative pupillary block, eliminating iridozonular contact. UBM of eyes with PDA has shown that pilocarpine not only eliminates the peripheral iris concavity and iridozonular contact, but causes a slightly convex contour. 10 Ideally, treatment would not only lower IOP but would eliminate iridozonular contact. Patients treated for prolonged periods with miotics develop reversal of the pigment signs of PDS and normalization of intraocular pressure. 12 Younger patients often cannot tolerate miotic drops, which produce accommodative spasm and blurred vision, but, in our experience, do well with pilocarpine Ocuserts, which deliver a sustained, low concentration of pilocarpine. 13, 14 More recently, laser iridotomy has been noted to eliminate the iris concavity. 1, 7, 8 Flattening of the iris concavity after iridotomy has been confirmed by UBM. 3, 10 There appear to be exceptions, however. 6 It has been hypothesisized that a reverse pupillary block prevents free passage of aqueous between the posterior and anterior chambers, resulting in a higher pressure in the anterior chamber than in the posterior chamber. 1, 7 Iridotomy equalizes the pressure differential between the two compartments. In our patient, laser iridotomy eliminated the iris concavity and produced a planar configuration, while pilocarpine produced a convex one. After exercise, there was moderate pigment liberation into the anterior chamber and a slight rise in IOP in the eye which had had the iridotomy, while pilocarpine in the fellow eye again completely prevented this phenomenon. Topical pilocarpine administered to the eye which had had the iridotomy successfully prevented pigment liberation during exercise. The fact that pigment liberation can still occur after iridotomy raises the possibility that pigment dispersion may be a result not only of the posterior concavity of the iris, but also of iris flaccidity. Miotic-induced relative pupillary block appears more effective than iridotomy alone at eliminating pigment liberation during vigrous exercise. Further investigation comparing the long-term effectiveness of miotic treatment and iridotomy at preventing progression of pigment dispersion appears warranted. REFERENCES
GlaucomaExperience with the Baerveldt Glaucoma Implant in Treating Neovascular Glaucoma Lloyd MA. Baerveldt G. Heuer DK. Minckler DS. Martone JF Ophthalmology ,July, 1995;102(7):1107-1118 In this study, 100 patients (103 eyes) who previously underwent Baerveldt implantation for glaucoma unresponsive to maximum medical therapy were retrospectively examined. The reasons for glaucoma were varied. 33% had neovascular glaucoma, 15% had congenital glaucoma and 15% had open angle glaucoma. The ethnic mix was also varied with 69% being white, 15% hispanic, 12% black and 5% asian. The phakic status was equally varied with 39% phakic, 39% pseudophakic and 22% aphakic. As for the Baerveldt size, slightly more than half had the 350mm implant. One additional important factor was that 28 eyes had undergone penetrating keratoplasty either prior to or during the surgical procedure for the Baerveldt. Criticisms:The study is retrospective. The title refers to the authors experience with neovascular glaucoma yet this diagnosis represents only 33% of the cases. The ideal study would be a prospective study using one sized Baerveldt implant (350mm according to the study), only one preÐoperative diagnosis, one implantation technique including tube inclusion during the early (question hypertensive) phase. I would also exclude patients who have undergone or require penetrating keratoplasty. 8 of the 28 eyes requiring penetrating keratoplasty prior to or during the surgical procedure ultimately rejected or failed. Given the restrictions for creating such a study, the results obtained may be the best data we can obtain. Positive Findings:Initial studies reported success rates with shunting devices from 58 to 83%. The overall success rate in this retrospective study was 72%. Success was defined as a pressure less than or equal to 21 mm of mercury. In order to be considered successful, no further surgical intervention including laser could be undertaken. In addition, loss of light perception vision qualified a patient as a failure. Use of glaucoma medications postÐoperatively was not an element of the author's qualification for success. 43% of the eyes required medication postÐoperatively. For intractable glaucomas having such devastating diseases as neovascular glaucoma or glaucoma refractory to standard guarded trabeculectomy procedures, the Baerveldt implant offers a reasonable alternative. It is easier to implant compared to a double plated molteno. However, as with all shunting devices the complication rate is fairly high. Diligent care and prompt intervention will minimize the long term consequences and one may begin to approach the excellent success rates the authors have achieved.
GlaucomaTreatment of Postfiltration Bleb Leaks with Autologous Blood M. Fran Smith, MD, Raymond G. Magauran, III, MD, Janet Betchkal, MD, J. William Doyle, MD, PhD Ophthalmology 1995;102:868-871 Six patients with persistent and recurrent bleb leaks were enrolled. Four had guarded trabeculectomy surgery with Mitomycin C augmentation, two had full thickness procedures. Each subject, with appropriate sterile techniques adhered to, had 2-3 ml of whole blood drawn from the antecubital vein using a 27 gauge needle. This was exchanged for a 30 gauge needle and directed into the subconjunctival tissue medial and lateral to the bleb. In each position .5 to 1ml of whole blood was injected. The blebs were not entered and all needle entry sites were seidel negative. The blood encircled the blebs; heme did not track into the bleb through a subconjunctival plane. The theory put forward is that the non-cellular components of whole blood diffuse in a subconjunctival plane, aiding the resolution of the leak. (This deserves further investigation and a follow-up paper was presented at ARVO using a rabbit model by J. William Doyle, MD, PhD et al.) Four of the six blebs remained leak free after 4-14 months follow-up, with IOPs 8-12 mmHg. Peribleb, autologous blood can be employed to control problematic bleb leaks prior to and possibly instead of surgical revision.
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