Ocular changes associated with topiramate

Psychotropic Drug-Induced Glaucoma: A Practical Guide to Diagnosis and Management

This article provides a practical review of the diagnosis and management of angle closure induced by psychotropic agents, including tricyclic antidepressants, antipsychotics and anticonvulsants. Selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, monoamine oxidase inhibitors and antipsychotics may trigger angle closure by influencing pupil configuration through adrenergic, anticholinergic, serotonergic or dopaminergic mechanisms. Patients with narrow iridocorneal angles are at risk, and these are more common in people with hypermetropia (near-sightedness), older people and individuals with an Asian background. These patients may benefit from a laser peripheral iridotomy, either prophylactically or to relieve an acute angle-closure episode. An idiosyncratic reaction to medications such as topiramate may lead to angle closure through an alternate mechanism, leading to a uveal effusion. Ophthalmological review may be considered prior to commencing medications in high-risk patients.

Transient myopic shift due to ciliary body detachment as the sole ocular manifestation of hypertensive emergency - A case report

Purpose

Hypertensive emergency usually presents to ophthalmologists in the form of hypertensive retinopathy. We present a case of hypertensive emergency that presented as bilateral transient myopic shift due to ciliary body detachment in the absence of any retinal pathology. The purpose of this paper is to showcase another ocular manifestation of hypertensive emergency.

Observations

A 35 year-old female with a blood pressure of 192/114 mmHg presented to the emergency department with headache and acute onset blurry vision. Computed Tomography (CT) of the head, and lumbar puncture were within normal limits. Visual acuity was counting fingers in the right eye and 6/90 in the left eye, both of which improved to 6/9 with −5.00 diopters spherical correction in the right eye, and −4.75 diopters correction in the left eye. Intraocular pressures were normal. Anterior chambers were shallow, and there were no retinal changes on dilated fundus examination. Enhanced-depth optical coherence tomography (EDI-OCT) showed bilateral increased choroidal thickness and ultrasound biomicroscopy (UBM) showed 360° ciliary body detachment with angle closure. With improved blood pressure control, her ciliary body detachment resolved and her refractive error returned to baseline.

Conclusions

& Importance: Hypertensive emergency may present with choroidal thickening with anterior ciliary body rotation and detachment. A review of medications is important, as this presentation has also been reported as a rare side effect of sulphonamide drugs. In the absence of retinopathy, UBM and EDI-OCT imaging should be considered in the acutely hypertensive patient presenting with myopic shift.

Evaluation of Ocular Side Effects in the Patients on Topiramate Therapy for Control of Migrainous Headache

INTRODUCTION

Topiramate, a sulfa-derivative monosaccharide, is an antiepileptic drug which is administered in the control of migraine. It is reported to cause various ocular side effects such as visual field defect and myopic shift. To investigate the alterations in refractive error, properties of the cornea and changes in the anterior chamber in patients that receive Topiramate for migraine control.

MATERIALS AND METHODS

This is a hospital-based, non-interventional, observational study that is conducted at Imam Hossein Hospital, affiliated to Shahid Beheshti University of Medical Sciences, Department of Neurology, in collaboration with the department of Ophthalmology. Thirty three consecutive patients with the diagnosis of migraine that were candidate for Topiramate therapy were recruited. Patients with history of ocular trauma or surgery, keratoconus, glaucoma, congenital ocular malformations and any history of unexplained visual loss were excluded. After thorough ophthalmic examination, all the patients underwent central corneal thickness (CCT) measurement, and Pentacam imaging (Scheimpflug camera) at the baseline. Various parameters were extracted and used for analysis. Anterior chamber volume (ACV), anterior chamber depth (ACD), and anterior chamber angle (ACA) measurement was performed. These measurements were repeated on day 30(th) and 90(th) after the initiation of Topiramate therapy. According to the normality tests, parameters with normal distribution were analysed using the repeated measures test and the remaining parameters (with non-normal distribution) were analysed using the non-parametric k-sample test. A p-value< 0.05 was considered statistically significant, according to Bonferroni post hoc correction.

RESULTS

There were 66 eyes of 33 patients under the diagnosis of migrainous headache, that Topiramate was initiated for headache control, included in the study. The mean value of refractive error had a statistically significant myopic change, from -0.23 diopters (D) at the baseline to -0.61 D at the 90(th) day of follow-up period (p-value < 0.001). Mean CCT was 531.43 μm at the baseline and increased to 534.72 μm at the 30(th) day, and 537.51 μm at the 90(th) day after the administration of Topiramate (p-value=0.001). Mean value of other parameters, ACV, ACD, and ACA, did not reveal statistically significant change.

CONCLUSION

Myopic shift and gradually increasing CCT in the patients after Topiramate administration should be considered before any refractive surgery. We found no gradual change in the anterior chamber and angle parameters in our patients in the 90 days of follow up. More studies with a longer duration of follow-up are needed to elucidate dose-dependent ocular manifestations.

Chronic cocaine effects in retinal metabolism and electrophysiology: treatment with topiramate

PURPOSE

Cocaine abuse is a major public health problem with multiple-related complications. Indeed, cocaine can affect almost every organ of the human body, but little is known about its effects on the visual system. The main purpose of this work was to study if topiramate was able to reverse changes in retinal metabolism and retinal function induced by chronic cocaine exposure in adult rats.

MATERIALS AND METHODS

Sixteen Wistar rats were treated with a daily oral dose of cocaine during 36 days. Sixteen rats receiving NaCl 0.9% served as controls. Eight control and eight cocaine animals were administered topiramate from day 18 to day 36 of the experiment. Malondialdehyde (MDA), glutathione (GSH) and glutamate content, as well as glutathione peroxidase (GPx) activity in retina tissue homogenates were determined. Retinal function was assessed by electroretinogram (ERG).

RESULTS

Glutamate concentration was increased in the retinas of cocaine-treated rats. No changes in oxidative stress parameters were observed in the retinas of cocaine-treated rats when compared with the control ones. Cocaine induced a decrease in the a-wave and b-wave ERG amplitude. The administration of topiramate reversed cocaine-induced increase in glutamate concentration and had little effect on a-wave and b-wave ERG amplitude. Topiramate, a drug used during the last decade for the treatment of epileptic seizures, is able to reverse the cocaine-induced alterations observed in retinal glutamate concentration.

CONCLUSIONS

We can conclude that retinal glutamate metabolism and function may be affected by exposure to cocaine. We confirm that topiramate, a treatment recently proposed for cocaine dependence, is also able to recover partially cocaine-induced changes in the retina.

Evaluation of the retinal changes in patients with chronic migraine

The aim of this study was to investigate retinal nerve fiber layer (RNFL) thickness and macular changes (central subfield thickness, cube average thickness, cube volume) in patients with chronic migraine (CM) without visual impairment using spectral-domain optical coherence tomography (SD-OCT) and to compare the results to healthy controls. A total of 80 subjects, including 40 CM patients (24 females, 16 males, [corrected] at 19-36 years of age) with no migraine prophylactic treatment and 40 healthy controls (22 females, 18 males, [corrected] at 20-40 years of age) were enrolled. Both eyes of patients with CM and controls were imaged using Cirrus HD SD-OCT (Carl Zeiss Meditec, Dublin, CA, USA). The average RNFL thickness was not significantly thinner in patients with CM. The mean average RNFL thickness was 83 ± 10.5 μm in CM patients and 85 ± 9.6 μm in healthy controls (p = 0.648), but superior quadrant RNFL thickness in the CM patients was significantly lower than healthy controls. The mean superior RNFL thickness was 86 ± 6.7 μm in CM patients and 108 ± 7.3 μm in controls (p < 0.001). Illness duration and frequency of the attacks were not affected by RNFL thickness. No significant differences were detected in macular changes between CM patients and healthy controls. In our study, the thickness of superior RNFL was found to be thinner in CM patients. This implies that longitudinal follow-up is needed to clarify whether RNFL thinning, in migraine patients, is related to a progressive loss of axons and retinal ganglion cells.

Topiramate maculopathy

The purpose of this study is to present the first case of a pure 'topiramate maculopathy' without acute glaucoma and/or myopia, which form the classical syndrome.

DESIGN

Interventional/observational case report.

SETTING

Institutional University Teaching Hospital.

PATIENT

A 22-year-old American female, after taking 100 mg of topiramate (Topamax®) a day for 6 days because of a migraine attack, complained of severe visual acuity deterioration of sudden onset in both eyes, regardless of distance (far or near), during the span of 1 day. A complete ocular examination was carried out. Best-corrected visual acuity (BCVA) in the right eye was hand motion and in the left eye was counting fingers. Cycloplegic refraction and pinhole did not improve the visual acuity of patient's eyes. The anterior chamber depth was normal in both eyes. Tonometry was 14 mmHg in both eyes. Fundus biomicroscopy disclosed a maculopathy with macular striae and a cellophane-like reflex. Optical coherence tomography (OCT) showed an undulating profile with congruent retinal folds and choroidal layers plicae. INTERVENTIONAL/OBSERVATION PROCEDURE: Immediate discontinuation of Topamax and steroid therapy.

MAIN OUTCOME MEASURES

BCVA, cycloplegic refraction, tonometry, fundus photography, and OCT. Three days after suspension of Topomax and steroid therapy the patient's BCVA was 6/6 in both eyes. Tonometry was 14 mmHg in both eyes. Fundus appearance and OCT features were nearly normal. After 2 years of follow-up, the patient's BCVA, tonometry, macula, and OCT are stable in both eyes. In conclusion, an isolated (unassociated with glaucoma and/or induced myopia) acute maculopathy, previously known as being part of a rare syndrome, has been identified, described, and documented.

Topiramate and the vision: a systematic review

BACKGROUND AND PURPOSE

Topiramate (TPM) is a sulfa-derivative monosaccharide that is used mainly for treating epilepsy and preventing migraine. Within the gamut of side effects attributable to this drug, ophthalmologic manifestations are of crucial importance. In this study, for the first time, the aim was to provide a systematic literature review regarding this issue.

METHODS

For the time period 1996-2011, a PubMed search was made for the studies concerning the adverse/beneficial effects of TPM on vision. Overall, 404 citations out of a total of 2756 TPM-related studies were examined for relevance.

RESULTS

A total of 74 relevant studies were reviewed, 65 of which comprise small observational studies describing the ophthalmic side effects of TPM in 84 patients. Of these patients, 66 were affected by ciliochoroidal effusion syndrome as the cardinal ocular side effect of TPM (17 cases of myopic shift and 49 cases of angle closure glaucoma). A comprehensive statistical analysis is provided on these 66 subjects. Other rare side effects of TPM on the vision were also reviewed, including massive choroidal effusion, ocular inflammatory reactions, visual field defects, probable effects on retina, cornea, and sclera, and neuroophthalmologic complications. In addition, a framework is provided to classify these results.

DISCUSSION

Due to the expanding spectrum of indications for the administration of TPM, neurologists and psychiatrists should be aware of its diverse ocular side effects. In conclusion, ocular complications following this drug should be taken seriously and be subjected to ophthalmic counseling.