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Causal factors responsible for optic and peripheral neuropathy, which plague the people inhabiting the tobacco-growing western province of Pinar del Rico, Cuba, may include toxic substances such as tobacco-alcohol or 'nutritional' amblyopia and cyanide from cassava. Deterioration in trade relations between Cuba and European countries, leading to food shortage and dietary changes among the Cuban population, may have contributed to this neuropathic illness which is associated with vitamin-B deficiency.

Reliable visual field testing is the gold standard in identifying future vision loss in patients with Idiopathic Intracranial hypertension (IIH). However, when field performance is unreliable, GCC analysis may be useful. We evaluated IIH patients over three visits: initial visit, follow-up visit and a third visit, almost 1 year later. We evaluated mean deviation (MD), GCC and RNFL at presentation and the second visit and compared it to the mean deviation (MD) on fields at the third visit. As early as the second visit, GCC loss correlated with visual field results seen at the third visit. [ABSTRACT FROM AUTHOR]

Purpose To determine whether a pattern of altitudinal ganglion cell loss, as detected and measured by optical coherence tomography (OCT), can be used to distinguish non-arteritic ischaemic optic neuropathy (NAION) from optic neuritis (ON) during the acute phase, and whether the rate or severity of ganglion cell loss differs between the two diseases. Methods We performed a retrospective, case-control study of 44 patients (50 eyes) with ON or NAION and 44 age-matched controls. Non-arteritic ischaemic optic neuropathy and ON patients had OCT at presentation and four consecutive follow-up visits. Controls had OCT at one point in time. The ganglion cell complex (GCC) was evaluated in the macula, and the retinal nerve fibre layer (RNFL) was evaluated in the peripapillary region. Ganglion cell complex thickness, RNFL thickness and GCC mean superior and inferior hemispheric difference were compared between NAION and ON patients at each time-point using unpaired t-tests and between disease and control subjects at first measurement using paired t-tests. Results Mean time from onset of symptoms to initial presentation was 10.7 ± 6.6 days in NAION and 11.7 ± 8.6 days in ON (p = 0.67). There was a significantly greater vertical hemispheric difference in GCC thickness in NAION patients than ON patients at all time-points (5.5-10.7 μm versus 3.1-3.6 μm, p = 0.01-0.049). Mean GCC thickness was significantly decreased at less than 2 weeks after onset in NAION compared to age-matched controls (72.1 μm versus 82.1 μm, p < 0.001), as well as in ON compared to age-matched controls (74.3 μm versus 84.5 μm, p < 0.001). Progression and severity of GCC and RNFL loss did not differ significantly between NAION and ON. Conclusion A quantitative comparison of mean superior and inferior hemispheric GCC thickness with OCT may be used to distinguish NAION from ON. [ABSTRACT FROM AUTHOR]

The objective of this study was to describe the changes in the retinal ganglion cell complex (GCC) relative to the retinal nerve fibre layer (RNFL) over time in Leber hereditary optic neuropathy (LHON) patients. Average RNFL and GCC thickness was measured in seven patients in the early acute (123, 68.4 μm), late acute (113.5, 57.4 μm), and chronic (72.7, 50.8 μm) phases. Patients showed thinning of the GCC with RNFL swelling in the early acute phase. GCC thinning became severe within weeks and persisted. RNFL swelling normalised during the late acute phase with eventual thinning in the chronic phase. GCC changes appear at the commencement of visual loss and in some cases prior to vision loss. These findings define an optical coherence tomography (OCT) profile in LHON. [ABSTRACT FROM PUBLISHER]

Following the epidemic of optic and peripheral neuropathy, which occurred in Cuba between 1991 and 1993, a number of patients have been re-evaluated, including testing with optical coherence tomography (OCT) and electrophysiology. At the same time, a number of patients with Leber’s hereditary optic neuropathy have also been evaluated. The purpose of this study was to detect residual loss of retinal nerve fibre layer (RNFL) in patients who suffered Cuban epidemic optic neuropathy (CEON), and to compare these findings with those in patients with Leber’s hereditary optic neuropathy (LHON). Optical coherence tomography as well as clinical examinations were performed on 11 patients diagnosed with CEON 15 years following the epidemic and 14 patients with LHON. OCT in CEON patients showed thinning of the RNFL in the temporal sector and normal thickness in other quadrants. However, patients with chronic LHON had more diffuse RNFL loss throughout the retina. OCT findings corresponded with clinical findings in CEON and LHON. There was drop out of the papillomacular bundle in both diseases. Two patients in the acute stages of LHON and three LHON carriers showed thinning of the temporal RNFL only. This is the first report of OCT in CEON that shows residual damage in the papillomacular bundle compared with chronic LHON where there is more diffuse and progressive loss of the RNFL. The importance of OCT for the diagnosis and evaluation of similar optic neuropathies is emphasised. [ABSTRACT FROM AUTHOR]

Epileptic activity can lead to the hallucination of simple forms like lights, colors, and shapes, or complex scenes. The alteration of a perceived form, called metamorphopsia, and the recurrence of a perceived image, called palinopsia, are more generally associated with structural lesions. However, in a 38-year-old woman, a structural lesion resulted in metamorphopsia and palinopsia only when periodic lateralized epileptiform discharges (PLEDs) were present. The patient had a malignant astrocytoma in the right parietal area and experienced occasional seizure activity. Astrocytoma is a tumor composed of astrocytes, which are cells that make up the supporting elements of the nervous system. The patient noticed that sometimes when looking from one object to the next, features of the first object would be superimposed on the second. Sometimes previously seen items would float in from the left and superimpose themselves on objects currently in the visual field. The visual disturbances and the PLEDs resolved slowly over time. Although most of the symptoms of PLEDs have little to do with complex visual phenomena, in this case, where the patient had a serious structural lesion, the PLEDs seemed to be necessary for the manifestation of the visual symptoms. (Consumer Summary produced by Reliance Medical Information, Inc.)

Abstract: Bernard Schwartz, MD, PhD (1927–2007) was first and foremost a scholar. He was a teacher, serving as Professor of ophthalmology for many years at Tufts University; an administrator, chairing the department of ophthalmology for over 20 years; a clinician, practicing primarily in the field of glaucoma; a scientist with a broad interest in ophthalmic research; an historian, especially of medical history; and an editor, primarily of Survey of Ophthalmology. Throughout all of his activities, the central theme was always scholarship. [Copyright &y& Elsevier]

Abstract: Charles Bonnet (1720–1792) was an eminent naturalist and philosopher whose contributions to botany and philosophy were highly regarded and honored by his contemporaries in the scientific community of his era in France and England. In1760 he first described and analyzed formed visual hallucinations experienced by his grandfather. The syndrome was named after Bonnet in 1937 by George de Mosier, another native of Geneva, Switzerland. [Copyright &y& Elsevier]

The antiarrhythmic agent, amiodarone (Cordone*, Pacerone*), has been reported to cause optic neuropathy. However, the clinical manifestations are similar to non-arteritic anterior ischemic optic neuropathy (AION), which makes diagnosing amiodarone optic neuropathy difficult. There is controversy whether or not amiodarone optic neuropathy actually exists as a distinct entity. The clinical manifestations and the proposed pathophysiology of amiodarone optic neuropathy are discussed. [ABSTRACT FROM AUTHOR]