Bilateral Retrobulbar Optic Neuropathy Research Articles

Ocular toxicity among patients taking anti-tubercular treatment.

Tuberculosis remains a major public health problem in Nepal and anti-tubercular drugs used for the treatment of pulmonary and extrapulmonary tuberculosis can be associated with ocular toxicity. This prospective study aimed to evaluate the incidence of ocular toxicity among patients receiving anti-tubercular therapy and to assess the change in visual functions and ocular imaging before and after use of anti-tubercular therapy. A total of 89 eyes of 45 TB patients taking anti-tubercular therapy were enrolled. Detailed history and examination including best-corrected visual acuity (BCVA), colour vision (Farnsworth D-15t), contrast sensitivity (Pelli-Robson chart), Goldman visual field analysis and spectral domain optical coherence tomography for retinal nerve fibre layer (RNFL) analysis were assessed at baseline and at 6 months after starting anti-tubercular therapy. Visual evoked potential (VEP) was performed in suspected cases. The mean age of the patients was 29.13±14.00 years and 62.2% were males. The mean weight of the subjects was 54.37±10.36 kg, mean daily dosage of ethambutol was 17.91±1.74 mg/day/kg and mean administration duration was 2.71±1.54 months. The incidence of ocular toxicity was 2.24%. Bilateral retrobulbar optic neuropathy occurred in a 27-year female of 55 kg receiving ethambutol (20 mg/kg/day) for 6 months for Pott's spine. Her best-corrected visual acuity in both eyes was reduced to 6/36 from 6/6 and developed non-specific color vision defect, decreased contrast sensitivity, bilateral cecocentral visual field defect and mean decrease in retinal nerve fibre layer thickness compared to the baseline data. In rest cases, a statistically significant decrease in mean retinal nerve fibre layer thickness in both eyes suggested the evidence of subclinical toxicity. Though less common, ethambutol toxicity can occur in patients under anti-tubercular therapy in the form of retrobulbar optic neuritis. Decreased contrast sensitivity and thinning in the mean retinal nerve fibre layer thickness can be the indicator of subclinical toxicity.

Macular ganglion cell complex measurement in bilateral retrobulbar optic neuropathy without a relative afferent pupillary defect.

PurposeThis study aimed to demonstrate the clinical usefulness of measuring the macular ganglion cell complex (GCC) for the early detection of axonal loss in eyes with bilateral retrobulbar optic neuropathies.Patients and methodsWe retrospectively reviewed the medical records of three patients with bilateral toxic, ischemic, or infiltrative retrobulbar optic neuropathy.ResultsNo relative afferent pupillary defect was detected in any patients. The results of the fundus examinations were unremarkable at the initial presentation except for slight optic disk pallor in the right eye of Case 3. Magnetic resonance imaging showed no abnormal findings in Cases 1 and 2. Measurement of the macular GCC clarified the presence of axonal loss in all three cases with diagnostic uncertainty. Although reduction in the macular GCC thickness was not observed initially in Case 2, it became evident later when both optic disks still appeared normal.ConclusionA reduction in the macular GCC thickness seemed to precede the appearance of optic disk pallor and occurs regardless of toxic, ischemic, or infiltrative retrobulbar optic neuropathy. The current case series suggested that measurement of the macular GCC facilitated early differentiation between bilateral retrobulbar optic neuropathy and nonorganic visual loss, which can otherwise be challenging in some cases.

Bilateral retrobulbar optic neuropathy as the only sign of zoledronic acid toxicity

IntroductionBisphosphonates may rarely cause ocular adverse effects and retrobulbar optic neuropathy (RON) secondary to zoledronic acid is very rare. Case reportA 67-year-old man was referred because of progressive and painless decrease vision in the left eye. He had been treated with 7 cycles of zoledronic acid infusions because of metastatic prostate cancer. On examination, VA was 20/20 in the right eye (OD) and 20/50 in the left eye (OS). The optic nerve was unremarkable OU. Pattern visual evoked potentials (pVEP) and electroretinography were performed with the result of VEP responses abolished in OS, and the VEP waveform within the normal range amplitude and delayed peak latencies in OD. Due to the high suspicion of bilateral RON secondary to zoledronic acid, we decided to discontinue the treatment. Two months later, VA was 20/20 OD and hand motions OS, with relative afferent pupillary defect and a pallor of the optic disc in OS. The diagnosis of bilateral RON secondary to zoledronic acid infusions was confirmed, and it was only partially reversible. DiscussionZoledronic acid is a potent new generation bisphosphonate increasingly used in oncologic patients and it is usually well tolerated. Optic nerve toxicity is not a side effect recognised by either the Food and Drug Administration or the drug manufacturers, and to our knowledge, this is the first case of zoledronic acid-related bilateral RON with late onset.In conclusion, patients treated with bisphosphonates should be informed about the possibility of ocular side-effects, and ophthalmologists should be consider discontinuing the drug.

Progressive outer retinal necrosis in an immunocompromised patient presenting with bilateral retrobulbar optic neuritis

Abstract Background: Progressive outer retinal necrosis (PORN) is a necrotizing chorioretinopathy caused by herpes simplex virus, varicella-zoster virus, or cytomegalovirus. Objective: To describe the clinical morphology of PORN presenting with asymmetrical isolated bilateral retrobulbar optic neuropathy. Method: The medical records of a 45-year-old human immunodeficiency virus infected patient presenting with bilateral visual loss at King Chulalongkorn Memorial Hospital were reviewed with respect for the privacy of patient. Result: Gradual visual loss progressed to no light perception in the right eye and 20/200 in the left eye within 1 month. The patient was initially diagnosed with retrobulbar optic neuritis in both eyes. The investigations included MRI, vitreous tapping, lumbar puncture, and serological testing. MRI elicited enhancement around both optic nerves, which suggested optic neuritis. Thereafter, multifocal areas of retinal necrosis developed with rapid progression and additional cutaneous zoster lesions were established. These findings led to a diagnosis of PORN. The patient was promptly treated with intravenous ganciclovir, anti-retroviral therapy, and vitrectomy with endophotocoagulation and silicone injection. Unfortunately, his visual prognosis in the left eye was still poor Conclusion: PORN was uncommonly present with bilateral isolated optic neuropathy before retinal lesions developed. Retrobulbar optic neuropathy from herpetic infection in immunocompromised patients should be considered despite a normal fundus at initial presentation. Early diagnosis and prompt intervention may preserve vision. This case demonstrates the importance of careful physical examination and follow up of retinal lesions.

Disulfiram-induced Bilateral Optic Disc Oedema with Disc-Related Visual Field Loss and Sparing of Central Vision

Disulfiram (Antabuse) is a synthetic compound used in the treatment of chronic alcohol addiction. Bilateral retrobulbar optic neuropathy with visual loss has been reported in patients receiving disulfiram. We describe the case of a 37-year-old man with bilateral optic disc oedema occurring after beginning a regimen of disulfiram. There were visual field defects as seen with local disease of the optic disc but not central visual loss as occurs typically in toxic optic neuropathy. Optic disc oedema improved promptly after discontinuation of the drug. After excluding all other causes of bilaterally swollen optic discs, ophthalmologists should be aware of this rare adverse effect of disulfiram in chronic alcoholics who develop bilateral optic disc oedema.

Folic acid deficiency optic neuropathy: A case report

IntroductionNutritional optic neuropathies are uncommon and can be associated with gradual visual loss and optic atrophy or sudden vision loss and optic disc swelling.Case presentationA 44-year-old woman presented with a 4-week history of progressive visual loss and was noted to have bilateral retrobulbar optic neuropathy. No other clinical abnormality was noted. Investigations revealed severe folate deficiency with normal vitamin B12 levels. Her alcohol and tobacco consumption was moderate and subsequent correction of folate levels with oral supplementation has led to improvement in her visual acuity.ConclusionThis case highlights an unusual presentation of folic acid deficiency that may present to the general physician.

Primary Sinonasal Undifferentiated Carcinoma Presenting With Bilateral Retrobulbar Optic Neuropathy

A 43-year-old man presented with acute bilateral visual loss. Ophthalmologic examination revealed no light perception in the right eye and a visual acuity of 20/50 in the left eye with a right afferent pupillary defect. Ophthalmoscopic examination was normal. Brain MRI showed an intracranial but extra-axial mass in the floor of the anterior cranial fossa extending along the olfactory groove and into the sinonasal vault. Endoscopic biopsy showed a high-grade neoplasm consistent with sinonasal undifferentiated carcinoma. This case report highlights an unusual clinical presentation for this rare and aggressive neoplasm.

A case of parainfectious retrobulbar neuritis with neuroimaging appearances of carcinomatous infiltration

A case of bilateral retrobulbar optic neuropathy in a 68-year-old female is presented. The initial clinical impression and optic nerve neuroimaging appearances were suggestive of carcinomatous infiltration. The subsequent favourable progress with a short course of high-dose corticosteroids was consistent with a parainfectious aetiology. Parainfectious optic neuritis is reviewed and the role of neuroimaging discussed.

Mieloneuropatía periférica y óptica en un paciente alcohólico deficiente en ácido fólico

In Western countries, neurological disorders secondary to toxic nutritional problems usually present as isolated cases that are generally associated to identifiable causes (alcoholism, eating disorders, absorption disorders, use of medicines) that reduce the availability of basic nutrients, especially B group vitamins, but also folic acid (FA). The optic nerves and the peripheral axons are frequent target organs in this type of pathology, but leukoencephalopathy and spinal cord involvement may also appear, often in combination. We describe the case of a 38-year-old female smoker with a heavy alcohol habit, who developed a subacute clinical pattern of, predominantly axonal, sensitive peripheral polyneuropathy, with vegetative fibre involvement. She also presented involvement of the posterior spinal cord, which gave rise to an ataxic disorder in the gait, as well as a severe bilateral retrobulbar optic neuropathy. Likewise, she presented macrocytosis (MCV: 118) due to megaloblastosis. She was also found to have a FA deficit but a normal vitamin B12 metabolism. With the help of supplementary vitamins, stopping drinking and the regularisation of her diet, the patient presented progressive clinical improvement, and was able to walk without support at 3 months and almost completely recovered her sight, which was corroborated by an improvement in the studies of both visual and somatosensorial evoked potentials. In our community, alcoholism is a frequent cause of nutritional deficiencies, which lead to neurological problems. FA is one of the nutrients that become deficient in alcoholics. More and more descriptions are being reported of peripheral polyneuropathy, retrobulbular optic neuropathy, myelopathy or leukoencephalopathy associated to FA deficiency, above all in patients with a history of alcoholism.