Vascular risk factors for central retinal artery occlusion.

PURPOSE: To determine the proportion of patients presenting with thromboembolic central retinal artery occlusion (CRAO) who had undiagnosed vascular risk factors amenable to modification. METHODS: A retrospective audit of consecutive patients with non-arteritic/thromboembolic CRAO presenting between 1997 and 2008 in a single tertiary teaching hospital. RESULTS: Thirty-three patients with non-arteritic CRAO were identified. Twenty-one patients (64%) had at least one new vascular risk factor found after the retinal occlusive event, with hyperlipidemia being the most common undiagnosed vascular risk factor at the time of the sentinel CRAO event (36%). Nine patients (27%) had newly diagnosed hypertension or previous diagnosis of hypertension but not optimally controlled. To better control their vascular risk factors 18 patients (54%) were given a new or altered medication. Nine patients had more than 50% of ipsilateral carotid stenosis ; six of these proceeded with carotid endarterectomy or stenting. One patient had significant new echocardiogram finding. Systemic ischaemic event post CRAO occurred in two patients with stroke and acute coronary syndrome. CONCLUSIONS: Patients presenting with CRAO often have a previously undiagnosed vascular risk factor that may be amenable to medical or surgical treatment. As this population is at a high risk of secondary ischaemic events, risk factor modification is prudent.

Central retinal artery occlusion: timing and mode of presentation.

BACKGROUND AND PURPOSE: Central retinal artery occlusion (CRAO) is a sudden, frequently irreversible, monocular vision loss, analogous to acute cerebral ischaemia. Thrombolysis may improve visual outcomes, but it is unclear what the acceptable timing of administration should be. We aim to ascertain, through audit, the timing and mode of presentation of individuals with potentially thrombolysable CRAOs. METHODS: A retrospective audit of patients with acute thromboembolic CRAO. RESULTS: Thirty-one patients were identified. Mean time from onset of vision loss to presentation was 31 +/- 65 h. Eighteen patients (58%) presented within 20 h of vision loss, and the majority presented first to a general practitioner. Fifteen patients (48%) were reviewed by an in-hospital ophthalmologist within 20 h of vision loss. The mean delay from the referring source to assessment by an in-hospital ophthalmologist was 5.2 h (median 3.3 h, range 50 min to 24 h). This delay was, on average, shorter for patients referred directly to an ophthalmology clinic. CONCLUSIONS: Just under half (48%) of our cohort of CRAO patients were reviewed by an in-hospital ophthalmologist within the 20-h therapeutic time window for thrombolytic therapy and thus could qualify for inclusion in a randomized controlled trial according to EAGLE inclusion criteria. If thrombolysis is proven to be a feasible and safe treatment in CRAO then public awareness should be raised of the symptoms and an efficient direct referral pathway to an in-hospital ophthalmologist established to aid treatment delivery.

Prevalence of exfoliation syndrome in central Sri Lanka: the Kandy Eye Study.

AIMS: To report the prevalence and correlates of exfoliation syndrome (XFS) in central, rural Sri Lanka. METHODS: A population-based, cross-sectional ophthalmic survey of inhabitants 40 years of age and over from villages in the Kandy District was conducted. Selection was randomised using a cluster sampling process. 1721 eligible participants were identified, 1375 participated. A detailed ophthalmic history and examination including ocular biometry was made of each participant. RESULTS: The prevalence of XFS was estimated to be 1.1% (95% CI 0.5 to 1.5%; 22 eyes). XFS was bilateral in eight subjects, unilateral in six subjects. Univariate analysis demonstrated a significant association between XFS and increasing age (p<0.001), increasing intraocular pressure (odds ratio 1.2; 95% CI 1.09 to 1.27; p<0.001), nuclear cataracts (odds ratio 1.92; 95% CI 1.47 to 2.51; p<0.001), visual impairment (odds ratio 9.72; 95% CI 3.01 to 31.44; p<0.001) and a history of hypertension (odds ratio 3.89; 95% CI 1.14 to 13.16; p = 0.030). CONCLUSION: XFS in this Sri Lankan population was associated with advanced age, raised intraocular pressure, nuclear cataracts, hypertension and visual impairment.

Maintenance of eupnea and gasping following alterations in potassium ion concentration of perfusates of in situ rat preparation.

Levels of extracellular potassium ion, above those in vivo, are required for the generation of rhythmic activities of in vitro preparations. Our purpose was to define whether hyperkalemia in the perfusate of an in situ preparation was likewise necessary for the expression of eupnea and gasping. Studies were performed using the in situ preparation of the juvenile rat, in which activity of the phrenic nerve was recorded as an index of the respiratory rhythm. Eupnea and gasping were impervious to modifications of potassium ion of the perfusate. Eupnea was maintained uninterrupted for more than 60 min whether the total concentration of potassium was hypokalemic (2.75 mM), normokalemic (4.0 mM), or hyperkalemic (6.25 and 7.75 mM). Gasping, with identical characteristics, was elicited at any concentration of potassium ion. We conclude that both eupnea and gasping are unaffected by modest changes in the concentration of potassium ion in the perfusate with which the in situ rat preparation is maintained. These results add further support to the conclusion that the in situ preparation represents a model that accurately reproduces mechanisms of rhythm generation of both eupnea and gasping in vivo.

Cerebral dominance and schizophrenia-spectrum disorders in adults with intellectual disability.

Studies of the general population without intellectual disability have suggested an association between atypical handedness and schizophrenia-spectrum disorders (SSDs). Mixed handedness is taken as an index of diminished cerebral dominance or laterality. The present study addressed the question of whether such findings extend to the neurodevelopmentally 'at risk' population of adults with intellectual disability and SSDs compared with appropriate controls. Fourteen patients with a dual diagnosis of intellectual disability and SSD were compared with 14 controls with intellectual disability alone. Assessments of self-reported hand preference and relative hand skill were completed. Self-report of hand preference revealed highly significantly greater mixed-handedness in the SSD group. Furthermore, relative hand skill performance was significantly diminished for the dominant hand. The discrepancy between dominant and non-dominant hand functioning was lower in the SSD group and this association was highly significant. The results of the present study support the usefulness of such detailed laterality assessment in this population. Mixed laterality, over and above that of the population with general intellectual disability and developmental disorder, was associated with SSD. These results are consistent with the neurodevelopmental hypothesis of schizophrenia and its cognitive neuropsychiatric/neuropsychological sequelae.

A systematic review of the evidence base for lifestyle planning in adults with learning disabilities: implications for other disabled populations.

OBJECTIVE: To carry out the first systematic review of the evidence base for lifestyle planning (LP) approaches in adults with learning disability/developmental disorder and to discuss implications for other handicapped/disabled groups. METHOD: Exhaustive review of relevant electronic databases, supplemented by appropriate hand-searching of journals and correspondence with key researchers. We gathered information from any papers reporting clear outcome measures. Quantitative and qualitative aspects of relevant studies are appraised. RESULTS: There are no randomized controlled trials of lifestyle planning in adults with learning disability/developmental disorder. There was one controlled trial. Five studies, with a total of 108 subjects clearly identified, report on some outcome data. CONCLUSIONS: There is surprisingly little evidence to support any form of lifestyle planning or lifestyle planning in general in the learning disability population. No statistically significant findings on positive outcomes with good statistical power exist. Limited data are presented to suggest certain desirable features of some methods of lifestyle planning in terms of process or outcome. However, there may be good ethical reasons for pursuing lifestyle planning with certain patient groups. Suggestions are made as to how further research may add to the evidence base for or against effective outcomes in different forms of lifestyle planning.