Yair Alster

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

PURPOSE To compare the effectiveness of sub-Tenons versus peribulbar anesthesia in extracapsular cataract surgery. SETTING Department of Ophthalmology and the Maccabi Eye Institute, Tel Aviv, Israel. METHODS Sixty-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. RESULTS One 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. CONCLUSION Sub-Tenons anesthesia led to less IOP elevation than peribulbar anesthesia and provided similarly good globe immobilization and approximately the same pain levels intraoperatively.

Interferon alpha-2a for proliferative diabetic retinopathy after complete laser panretinal photocoagulation treatment.

BACKGROUND AND OBJECTIVE The aim of this study was to investigate the effect of interferon alpha-2a, an angiogenesis inhibitor, on eyes with active neovascularization after complete laser panretinal photocoagulation treatment. PATIENTS AND METHODS Eight patients with active neovascularization persisting for 6 months or more after completion of full panretinal photocoagulation were included in the study. All patients were treated with subcutaneous injections of 6 million international units of interferon alpha-2a, 3 times a week, for an average period of 10 months. Visual acuity, contrast sensitivity, blood tests, fundus photographs, fluorescein angiography, and physical examination were performed periodically. The main outcome measures were visual acuity and extent of neovascularization as assessed by fundus photography and fluorescein angiography. RESULTS The 5 men and 3 women (mean age, 60 years) had a mean duration of diabetes of 19 years. The average study follow-up was 42.2 +/- 8.7 weeks. Visual acuity and extent of neovascularization improved or remained stable in 7 patients. In none of the patients was there progression of neovascularization, but in 1 patient it could not be assessed due to vitreous hemorrhage. Most patients had malaise during the first weeks of treatment, but none of the patients suffered from nonreversible side effects associated with interferon alpha-2a. CONCLUSION This pilot study provides evidence that interferon alpha-2a might have a role in the regression of proliferative diabetic retinopathy and that further investigation is warranted.

Macular hole secondary to branch retinal vein occlusion diagnosed by Retinal Thickness Analyzer.

The Retinal Thickness Analyzer is a laser slit biomicroscopy imaging device that produces accurate measurements of retinal thickness and displays the images in a two-dimensional pattern, superimposed on a fundus image. This article reports a patient with decreased vision following branch retinal vein occlusion in whom the Retinal Thickness Analyzer was used to establish the diagnosis of a macular lamellar hole that was not apparent clinically.

Intraocular penetration of vancomycin eye drops after application to the medial canthus with closed lids

AIMS To investigate the intraocular penetration of vancomycin eye drops and to compare the conventional method of drop instillation to the lower cul de sac with applying drops to the medial canthus with closed lids. METHODS This prospective randomised trial evaluated 53 eyes of 53 patients who had undergone extracapsular cataract extraction (ECCE) with intraocular lens implantation. Vancomycin (50 mg/ml) eye drops were applied to either the lower cul de sac with open lids (conventional method), or to the medial canthus with the patient in a supine position and with closed lids. After paracentesis performed during ECCE, an aqueous humour sample was taken and vancomycin concentration was measured using the TDX vancomycin assay (fluorescence polarisation immunoassay). RESULTS Vancomycin concentration in the anterior chamber were above the minimal inhibitory concentration for Gram positive bacteria in the two methods of drop instillation examined (2.04 (SD 1.9) μg/ml and 1.49 (1.1) μg/ml in the open and closed methods, respectively (p =0.202)). CONCLUSIONS Vancomycin (50 mg/ml) reaches therapeutic concentration in the anterior chamber after topical drop application. Comparable concentrations were reached when drops were applied in either the lower cul de sac or to the medial canthus with closed lids. The latter method is proposed as likely to improve patient compliance.

Preferential Hyperacuity Perimetry to detect hydroxychloroquine retinal toxicity.

Purpose: To determine if Preferential Hyperacuity Perimetry (PHP) testing can detect the presence of retinal toxicity due to hydroxychloroquine (HCQ) or chloroquine administration. Methods: Fifteen patients were divided into three groups. Five patients had confirmed HCQ or chloroquine toxicity, five patients had suspected HCQ toxicity, and five patients had history of long-term use of HCQ or chloroquine but no evidence of toxicity. All patients underwent PHP testing. Results: All patients with either known or suspected toxicity based upon standardized visual field testing and/or fluorescein angiography demonstrated significant hyperacuity defects on PHP testing. None of the patients on long-term HCQ therapy, without clinical suspicion of toxicity, demonstrated a PHP hyperacuity defect. Conclusion: Results of this pilot study with patients with known or suspected HCQ or chloroquine toxicity suggest that PHP may be a useful adjunct for testing of patients suspicious for toxicity due to these medications. Further testing is warranted.

Colchicine in tear fluid of treated patients with familial Mediterranean fever.

Purpose. The study aimed to determine whether detectable concentrations of colchicine are present in the tear fluid of treated patients with familial Mediterranean fever (FMF) and thus demonstrate a possible route by which colchicine reaches the corneal surface. Methods. Tear fluid samples (50–100 &mgr;L) were collected from eight FMF patients on long-term colchicine treatment. Colchicine tear fluid concentrations were determined in all patients by radioimmunoassay using goat anticolchicine antibodies and [3H]colchicine (Dupont, Wilmington, DE). Results. Detectable concentrations of colchicine, with no apparent effect on the ocular surface, were found in all tear fluid samples (median, 0.46 ng/mL; range, 0.24–1.05 ng/mL). Conclusions. This study provides evidence of the route by which colchicine, given systemically, reaches the corneal surface and thus gives credence to the possible inhibitory effect of this drug on corneal wound healing in the cases described in the literature.

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.

Visual loss following high-dose cytosine arabinoside (ARA-C)

To the Editor: Cytosine arabinoside (ARA-C) is a pyrimidine analog of proven bene®t in the treatment of acute myelogenous leukemia (AML) including central nervous system involvement. Since the introduction of high-dose regimens, neurologic toxicity of intravenous ARA-C has become noticeable (1, 2). Important predisposing risk factors include cumulative doses, age >60 yr, renal impairment and hepatic dysfunction (3). The neurotoxicity is predominantly cerebellar and manifested as dysarthria, ataxia and lack of coordination (1, 2). Less commonly cerebral toxicity manifests as somnolence and confusion or psychosis; seizures have been described and, rarely, peripheral neuropathy (4). Spontaneous recovery occurs in most patients after stopping the drug. We describe a case of persistent optic neuropathy leading to severe visual loss following administration of high-dose ARA-C. A 33-yr-old woman was diagnosed with AML (M4 subtype). She received induction therapy with a combination of low-dose ARA-C (continuous infusion at 100 mg/m for 7 d), idarubicin and etoposide. Post-induction she developed sepsis and transient renal failure attributed to the use of aminoglycosides (creatinine up to 265 mmol/L). After recovery, her bone marrow aspiration (BMA) revealed a complete remission, and highdose ARA-C (3 g/m every 12 h for 3 alternate days) was given as a consolidation therapy. One week later the patient developed fever 39uC and neurological symptoms: ataxia, dysarthria and a lack of coordination compatible with a diagnosis of acute cerebellitis. Computerized tomography (CT) of the brain and lumbar puncture (LP) were normal. EEG was not contributory. The patient received antibiotics, with improvement of the fever and neurologic symptoms. However, a week later she developed a gradual loss of vision in both eyes which progressed to severe visual loss (®nger counting and 1/18 in the right and left eyes, respectively). Fundus examination showed blurring and swelling of the disc margins with scattered retinal hemorrhages. Repeat brain CT and MRI showed no signs of leukemic in®ltration. LP was normal and BMA showed no evidence of leukemia. During the next 4 months her visual acuity gradually improved to 1/ 6 and 20/130 in the right and left eyes, respectively. A right relative afferent pupillary defect (+1) was observed. Optic disc swelling resolved and temporal optic pallor was observed. Most retinal hemorrhages have resolved. She is still in complete remission of the leukemia. The mechanism of ARA-C neurotoxicity is unknown. High CSF levels of ARA-C and its active metabolites are achieved after systemic highdose therapy. In the absence of cytidine deaminase from the CNS, ARA-C is not catabolized to the inactive metabolite uracil arabinoside. Thus, supratherapeutic levels of the drug can be maintained in the CSF for the duration of high-dose ARA-C therapy, although no study had shown signi®cant association between neurotoxicity and plasma or CSF drug levels (4). Neurotoxicity of ARA-C, especially cerebellar dysfunction, have been extensively reported with an incidence of 10±15% (1, 2, 5). Optic neuropathy has been described once before (5). In our case there was a strong temporal relationship between the administration of high-dose ARA-C and the occurrence of visual loss. Leukemic involvement and infection of CNS were excluded. Neurotoxicity from high-dose ARA-C has been usually noted 3±8 d after initiation of the treatment (4). In our case cerebellar dysfunction appeared 1 wk after treatment with ARA-C, and visual loss appeared a week later. The dosage of ARA-C precipitating neurotoxicity is usually in the range of 36 g/m, but the syndrome has been reported with cumulative dose as low as 15 g/m (1, 5). Our patient received 18 g/m. The transient impairment of renal function in our patient could have contributed to the development of neurotoxicity. Eur J Haematol 2000: 64: 208±209 Printed in UK. All rights reserved Copyright # Munksgaard 2000

A novel high-resolution kinetic method for visual field mapping of scotoma in age-related macular degeneration.

BACKGROUND AND OBJECTIVE To examine a new high-resolution kinetic mapping method for scotoma in age-related macular degeneration. PATIENTS AND METHODS A computer-based program for kinetic visual field mapping was tested in 10 healthy subjects and 14 patients with age-related macular degeneration and fixed preferred retinal locus. The stimulus was presented using a back projector on a screen located 40 cm from the subject. The findings were then compared with static results. RESULTS Control group mapping revealed good congruency with the anatomic blind spot. Mapping of the 14 patients with age-related macular degeneration was rapid and revealed good accuracy. The average deviation of the mapping border from the anatomic scotoma border was no more than 3.1% of the scotoma radius. Static mapping of 7 of the patients with age-related macular degeneration was longer and revealed lower accuracy. CONCLUSIONS The proposed method is more rapid, accurate, and consistent than static mapping. It allows accurate mapping of central scotoma with suprathreshold stimulus, and may be used in the future for detecting the early stages of age-related macular degeneration using subthreshold stimulus.