Moshe Lazar

Retinal vein occlusion associated with methylenetetrahydrofolate reductase mutation

OBJECTIVEnTo report on the occurrence of methylenetetrahydrofolate reductase (MTHFR) deficiency in patients with retinal vein occlusion (RVO).nnnDESIGNnProspective case seriesnnnPARTICIPANTSnFifty-nine consecutive patients with newly diagnosed RVO seen at the Retina Unit in the Tel Aviv Medical Center during 1997. METHODS/TESTING: Interviews and multiple blood analyses were done. Data were compared to the reported incidence of MTHFR deficiency in the Israeli population at large.nnnRESULTSnTwenty-six patients (44.1%) were heterozygotes and 11 (18.6%) were homozygotes for 677C-T mutation in MTHFR. The MTHFR 677C-T homozygosity was documented as being present in 10.4% of healthy individuals in the Israeli population. The difference in homozygosity was found to be statistically significant (P = 0.038).nnnCONCLUSIONSnRetinal vein occlusion may be associated with a mutation in MTHFR.

Retinal pathology occurring after excimer laser surgery or phakic intraocular lens implantation: evaluation of possible relationship.

The increasing number of patients undergoing refractive surgery has led to an awareness of the potential retinal complications of these procedures. The purpose of this review is to summarize the reports of retinal pathology and myopic maculopathy that have occurred after excimer refractive surgery or implantation of phakic intraocular lenses, and to evaluate theoretical pathogenetic mechanisms. We found it reasonable to conclude that retinal detachments and macular hemorrhages are not caused by laser surgery, but are rather characteristic of the natural history in the myopic eye. However, although there is no clear-cut evidence for a cause-and-effect relationship between excimer laser surgery and retinal pathology, it is very important to inform patients that refractive surgery only corrects the refractive aspect of myopia, and that the myopia itself still has the potential for serious complications.

Effect of sub-Tenon’s and peribulbar anesthesia on intraocular pressure and ocular pulse amplitude

Purpose: To compare the effect of peribulbar and sub‐Tenons anesthesia on intraocular pressure (IOP) and ocular pulse amplitude (OPA) in the injected eye and the fellow noninjected (control) eye. Setting: Tel Aviv Medical Center, Tel Aviv, Israel. Methods: This prospective study measured IOP and OPA at baseline and 1 and 10 minutes after administration of lidocaine anesthesia in 40 consecutive adult patients having elective cataract surgery. Results: The IOP remained stable throughout the study with both modes of anesthesia. One minute after injection of the anesthetic agent, the OPA was significantly decreased in the injected eyes in both the sub‐Tenons (24%; P < .05) and peribulbar (25%; P < .05) groups. The decrease in the OPA in the sub‐Tenons group (14%; P < .05) was detectable after 10 minutes in the control eyes. In the peribulbar anesthesia group, the OPA in the control eyes increased significantly (9%; P < .05) 1 minute after injection of the anesthetic agent, returning to preinjection levels 10 minutes after the injection. Conclusions: The OPA in the eyes in which lidocaine was injected decreased significantly in both the sub‐Tenons and peribulbar groups. These findings have implications for the management of patients whose ocular circulation may be compromised.

Bilateral Retinal Vein Occlusion Associated With 5,10-Methylenetetrahydrofolate Reductase Mutation

PURPOSEnTo report on the occurrence of 5,10-methylenetetrahydrofolate reductase (MTHFR) deficiency, known to cause mild to moderate hyperhomocystinemia and increased risk of vascular occlusive disease, in a young patient with bilateral central retinal vein occlusion.nnnMETHODSnA 25-year-old man was initially examined with central retinal vein occlusion in the right eye, followed 4 months later by a central retinal vein occlusion in the left eye. Studies for risk factors predisposing to thrombosis were performed.nnnRESULTSnHematologic studies failed to detect any pathology. However, the patient was found to be homozygous for 677C-T mutation in MTHFR enzyme.nnnCONCLUSIONnCentral retinal vein occlusion may be associated with a mutation in MTHFR.

Effectiveness of sub-Tenon’s versus peribulbar anesthesia in extracapsular cataract surgery ☆

PURPOSEnTo compare the effectiveness of sub-Tenons versus peribulbar anesthesia in extracapsular cataract surgery.nnnSETTINGnDepartment of Ophthalmology and the Maccabi Eye Institute, Tel Aviv, Israel.nnnMETHODSnSixty-four consecutive patients who had extracapsular cataract surgery were randomized to have sub-Tenons or peribulbar anesthesia. Intraocular pressure (IOP) was measured before and 1 and 10 minutes after injection. The motility of the rectus muscles was evaluated before and 20 minutes after the injection, and the patients anxiety level was recorded immediately after the injection. Pain was assessed intraoperatively and 1 and 24 hours postoperatively by patient self-grading.nnnRESULTSnOne minute after the injection, IOP increased significantly in the peribulbar group (mean 7.97 mm Hg +/- 8.80 [SD]) (P < .05). There was no significant increase in the sub-Tenons injection group (mean 0.12 +/- 3.09 mm Hg). In both groups, IOP returned to preinjection levels by 10 minutes postoperatively. Patients with peribulbar anesthesia reported a significantly higher level of anxiety than those who had sub-Tenons anesthesia (P < .05). Although the intraoperative pain levels were the same, the sub-Tenons group reported significantly higher levels of pain 1 and 24 hours postoperatively; 16% in the sub-Tenons group and none in the peribulbar group reported moderate pain 24 hours after anesthesia. Ocular motility was the same except for the inferior rectus muscle, which was less motile on average in the peribulbar group.nnnCONCLUSIONnSub-Tenons anesthesia led to less IOP elevation than peribulbar anesthesia and provided similarly good globe immobilization and approximately the same pain levels intraoperatively.

Characteristics and outcomes of paediatric rhegmatogenous retinal detachment treated by segmental scleral buckling plus an encircling element.

Purpose To evaluate the outcome of paediatric rhegmatogenous retinal detachment treated by segmentai scierai buckling plus an encircling element.Methods A retrospective review was carried out of 15 consecutive paediatric patients (16 eyes).Results Thirteen of the 15 patients were male (87%), 2 (13%) were female. Their average age was 10.9 years (range 6-18 years; median 10 years). Retinal detachment was caused by trauma in 9 of 16 eyes (56%), high myopia in 5 of 16 eyes (31%) and had an unknown cause in 2 of 16 eyes (13%). Diagnosis was delayed by more than 1 month in 10 of 16 eyes (63%). The visual acuity was 6/60 or worse and the macula was detached on presentation in 13 of 16 eyes (81%). Two of 16 eyes (13%) had mild proliferative vitreoretinopathy. Final reattachment was achieved in all cases. Of 11 eyes with a follow-up of 6 months or more, there was improvement in visual acuity in 7 (63%), and a best-corrected visual acuity of 6/20 or better in 5 (46%).Conclusion Paediatric rhegmatogenous retinal detachment is characterised by a delay in diagnosis and a high degree of macular involvement on presentation. Anatomical reattachment with segmentai scierai buckling plus an encircling element was successful in all eyes, and improvement of visual acuity was achieved in one-half of the eyes which had a follow-up of 6 months or more.

Delay of Corneal Wound Healing in Patients Treated with Colchicine

BACKGROUNDnColchicine has a known adverse effect on wound healing through its inhibitory effect on tubulin-dependent cell functions and through collagenase activation. In the cornea, it has been shown in animal and in vitro studies to inhibit epithelium mitosis, fibroblast mitosis and migration, as well as to reduce collagen deposition. The authors report on two patients with corneal ulcers refractory to conventional treatment while the patients were undergoing oral colchicine therapy.nnnCASE REPORTSnThe first patient was an 86-year-old woman who had been treated with oral colchicine because of rheumatoid arthritis. She was admitted to the authors department with a deep corneal ulcer in the right eye for which she had been treated for 3 weeks with local antibiotics without any improvement. The second patient, a 60-year-old woman, was hospitalized because of a corneal ulcer in her left eye. She had been receiving oral colchicine therapy for mixed connective tissue disease. Treatment with local antibiotics was initiated but the condition of the eye worsened, ultimately resulting in corneal perforation.nnnRESULTSnWithdrawal of oral colchicine therapy was followed by rapid corneal wound healing in both patients.nnnCONCLUSIONnThe findings in these two patients suggest that colchicine may delay corneal wound healing. The authors suggest that in patients with corneal ulcers refractory to conventional treatment who are receiving colchicine, cessation of colchicine therapy should be considered.

Clonidine provides an allergy-free alternative in glaucoma patients with proven allergy to apraclonidine

Abstractu2002· Purpose: The aim of this study was to determine allergic responses to clonidine hydrochloride 0.25% in glaucoma patients with proven allergic reaction to apraclonidine 0.5%.u2002· Methods: Fifteen consecutive glaucoma patients with allergic reaction to apraclonidine were prospectively challenged with clonidine hydrochloride 0.25% and evaluated for recurrence of allergic reactions and efficacy of treatment. Intraocular pressure (IOP), conjunctival hyperemia, blood pressure and resting pulse rate were determined at baseline and after 1, 3, 6 and 12 months.u2002· Results: None of the patients developed ocular allergic reaction during 12 months on clonidine therapy. Blood pressure and pulse rate did not change significantly with clonidine treatment. Clonidine caused a significant reduction of IOP from baseline. In one patient, topical clonidine caused fatigue, dizziness and dry mouth.u2002· Conclusion: Clonidine did not cause allergic reaction in patients with proven allergy to apraclonidine, indicating that there is no cross-reactivity with apraclonidine. Due to the small series, however, we cannot assume that allergy will not occur with clonidine 0.25% given time and a larger number of patients.

Capsular bag distension associated with sulcus implantation of intraocular lenses

Abstract Capsular bag distension syndrome after endophacoemulsification and in‐the‐bag intraocular lens (IOL) implantation has been reported. We describe 2 cases in which sulcus implantation of a posterior chamber IOL caused marked capsular bag distension. Both cases resolved with conservative treatment or a neodymium:YAG posterior capsulotomy.

Dapiprazole for patients with night haloes after excimer keratectomy.

Abstract• Background: Haloes causing difficulties during night driving are one of the common complications of photorefractive keratectomy (PRK). The presumed reason for this phenomenon is the different refraction of light through the treated and untreated areas of the cornea. Its magnitude is proportional to the ratio between the treated area and pupil size. At nighttime, when the pupil dilates, rays from treated and untreated areas of the cornea reach the retina at different foci and produce haloes. We investigated whether dapiprazole, a miotic α-blocker drug, would be helpful in reducing night haloes in patients after PRK. • Methods: Twenty-four patients who complained of night haloes after PRK participated in our study. All were given dapiprazole 0.5% before night driving. Change in pupil size was recorded, and all patients completed a questionnaire on changes in the severity of haloes after instillation of dapiprazole. • Results: Improvement was described as very significant in five patients, moderate in ten and slight in seven. There was no improvement in two patients. The only side effect was slight irritation, which resolved within 1 h. • Conclusion: Our results demonstrate that dapiprazole improves the subjective discomfort caused by night haloes in post-PRK patients.