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N Sarvananthan

Publications and source records attributed to N Sarvananthan.

6 recordsLinked to original sources
PubMed2006

Survey of management of acquired nystagmus in the United Kingdom.

PURPOSE: To determine the current management of acquired nystagmus by ophthalmologists and neurologists. METHODS: Questionnaires were sent to ophthalmologists (850) and neurologists (434) in the United Kingdom. Estimated numbers of patients seen with acquired nystagmus, treatment options used, and the results of treatment of the patients were collected. RESULTS: Response rate was 37% for ophthalmologists and 34% for neurologists. The most common causes of acquired nystagmus were estimated to be multiple sclerosis and stroke. 58% of ophthalmologists and 94.5% of neurologists reported seeing patients with nystagmus. The most commonly used medical treatment was gabapentin and baclofen. Other drugs used were clonazepam, carbamazepine, benzhexol, ondansetrone, buspirone, memantine, and botulinum toxin (n=3). Eleven ophthalmologists and 52 neurologists noted symptomatic improvement with medical treatment. Eleven ophthalmologists and 44 neurologists noted improvement in visual acuity (VA). Occurrence of side effects noted with baclofen and gabapentin treatments were similar. CONCLUSION: A variety of drugs are used to treat acquired nystagmus in the UK. Baclofen and gabapentin are the drugs most commonly used and are reported to cause significant improvement in symptoms and VA. Better knowledge of the action of drugs in nystagmus is needed to establish guidelines and to give patients wider access to treatment.

Amines↗
PubMed2006

The effects of gabapentin and memantine in acquired and congenital nystagmus: a retrospective study.

BACKGROUND: Pharmacological treatment has been successful in some forms of acquired neurological nystagmus. However, drugs are not known to be effective in idiopathic infantile nystagmus or nystagmus associated with ocular diseases. METHODS: The authors retrospectively analysed Snellen visual acuity (VA), subjective visual function, and eye movement recordings of 23 patients with nystagmus (13 secondary to multiple sclerosis, three associated with other neurological diseases, two idiopathic infantile, and five with associated ocular diseases) treated with gabapentin or memantine. RESULTS: With gabapentin, 10 of 13 patients with nystagmus secondary to multiple sclerosis (MS) showed some improvement. Memantine improved the VA in all three patients with MS who did not improve on gabapentin. There was no change of nystagmus in other neurological disorders. Patients with congenital nystagmus showed reduction of nystagmus and their VA changes depended on the ocular pathology. CONCLUSION: Gabapentin and memantine may be effective in acquired nystagmus secondary to MS. To the authors' knowledge this is the first series of patients showing that gabapentin is effective in improving nystagmus in congenital nystagmus/nystagmus associated with ocular pathology. Memantine may be useful as an alternative drug in treating patients with nystagmus.

Adolescent↗
PubMed2000

Does ethnic origin influence the incidence or severity of keratoconus?

PURPOSE: Keratoconus affects all races, yet very little information exists as to the relative frequency in patients of different ethnic origin. We aimed to establish the incidence and severity of keratoconus in Asian and white patients. METHODS: The hospital records of the ophthalmology department of a large Midlands hospital with a catchment population of approximately 900,000 (87% white, 11% Asian, 2% other) were examined retrospectively for the 10 year period from 1989 to 1998. RESULTS: For the age group 10-44 years the prevalence of keratoconus in Asians and whites was 229 and 57 per 100,000 respectively, a relative prevalence of 4 to 1. The incidence of keratoconus in the same age group was 19.6 and 4.5 per 100,000 per year respectively, a relative incidence of 4.4 to 1. Asians were significantly younger at presentation compared with whites (mean 22.3 +/- 6.5 vs 26.5 +/- 8.5 years, p < 0.0001). A first corneal graft was carried out on 14% of the Asian and 15% of the white patients. Of those having grafts, Asians were significantly younger than white patients at the time of diagnosis (mean 19.1 +/- 4.8 vs 25.7 +/- 7.3 years, p = 0.005) and at operation (mean 21.4 +/- 5.0 vs 28.7 +/- 7.7 years, p = 0.004). The interval from diagnosis to operation, though shorter for Asians, was not significantly different (mean 1.8 +/- 1.4 vs 2.5 +/- 1.7 years, p = 0.2). CONCLUSION: The results show previously unrecognised racial differences in the hospital presentation of keratoconus in the UK. Compared with white patients, Asians have a fourfold increase in incidence, are younger at presentation and require corneal grafting at an earlier age.

Adolescent↗
PubMed1999

Synthetic hydroxyapatite orbital implants: a clinical and MRI evaluation.

PURPOSE: Coralline hydroxypatite orbital implants have been used since the 1980s. More recently, synthetic hydroxyapatite orbital implants have been used, in both primary and secondary orbital implantation surgery. The implant may be drilled and pegged, if required, after adequate vascularisation of the implant has occurred. In this study we evaluated the clinical results and vascularisation of synthetic hydroxyapatite orbital implants. METHODS: Twelve consecutive patients who had synthetic hydroxyapaptite orbital implants were evaluated clinically and 8 of these patients had orbital magnetic resonance imaging (MRI) scans with intravenous gadolinium performed at least 9 months post-operatively to assess vascularisation of the implant. Six patients had primary orbital implants at the time of enucleation and 6 patients had secondary implants. RESULTS: No significant complications occurred following insertion of the synthetic hydroxyapatite orbital implants. All patients reported cosmetic satisfaction with the results of surgery. MRI scans revealed inhomogeneous enhancement in 3 of the 4 patients receiving primary implants. All patients with secondary implants and 1 patients who had a primary implant had moderate to large areas of poor enhancement in the implant. CONCLUSION: Synthetic hydroxyapatite implants gave good clinical results but variable vascularisation occurs, especially with secondary implants.

Adolescent↗