Structural neuroimaging correlates of allelic variation of the BDNF val66met polymorphism.

BACKGROUND: The brain-derived neurotrophic factor (BDNF) val66met polymorphism is associated with altered activity dependent secretion of BDNF and a variable influence on brain morphology and cognition. Although a met-dose effect is generally assumed, to date the paucity of met-homozygotes have limited our understanding of the role of the met-allele on brain structure. METHODS: To investigate this phenomenon, we recruited sixty normal healthy subjects, twenty in each genotypic group (val/val, val/met and met/met). Global and local morphology were assessed using voxel based morphometry and surface reconstruction methods. White matter organisation was also investigated using tract-based spatial statistics and constrained spherical deconvolution tractography. RESULTS: Morphological analysis revealed an "inverted-U" shaped profile of cortical changes, with val/met heterozygotes most different relative to the two homozygous groups. These results were evident at a global and local level as well as in tractography analysis of white matter fibre bundles. CONCLUSION: In contrast to our expectations, we found no evidence of a linear met-dose effect on brain structure, rather our results support the view that the heterozygotic BDNF val66met genotype is associated with cortical morphology that is more distinct from the BDNF val66met homozygotes. These results may prove significant in furthering our understanding of the role of the BDNF met-allele in disorders such as Alzheimer's disease and depression.

Analysis of cataract referrals from community optometrists and general practitioners and subsequent clinic visit outcomes in a university hospital in the west of Ireland.

BACKGROUND: Studies published from hospitals in other countries have reported rates of between 69 and 90% of cataract referrals being listed for surgery (1-3). This potentially represents unnecessary outpatient appointments, time off work and transport costs for patients and carers (2). AIMS: Our first primary endpoint was to assess the number of cataract referrals listed for surgery. Our second primary endpoint was to assess the number of cataract referrals which included the following: (i) that visual loss from the cataract resulted in a detrimental effect on the patient's lifestyle, (ii) that the patient was willing to have surgery and (iii) that the patient was symptomatic from their cataract. METHODS: This project followed the Declaration of Helsinki. This was a retrospective study. RESULTS: Between February 2021 and February 2022, 198 patients were seen in Mr. PM's cataract clinic. Overall, 129 patients (67.5%) were listed for cataract surgery. Forty-seven referrals (23.7%) reported that the cataract was having a detrimental effect on the patient's life and these patients were more likely to be listed for surgery (93.6% vs. 59.2%, p = 0.00). Twenty-five referrals (12.6%) reported that the patient was willing to undergo surgery and these patients were more likely to be listed for surgery (88% vs. 64.8%, p = 0.02). A total of 130 referrals (65.7%) reported that the patient was symptomatic from their cataract and these patients were more likely to be listed for surgery (81.5% vs. 38.3%, p = 0.00). CONCLUSIONS: It is possible that an appropriately focussed referral form will aid in triaging cataract referrals and potentially reduce unnecessary appointments.

Virtual triaging in an eye emergency department during the COVID-19 pandemic.

AIM: The aim of this audit was to assess the effect of new guidelines on virtual triage referrals to an Irish eye emergency department (EED) during the COVID-19 pandemic. METHODS: A retrospective phone triage referral and clinical note audit was performed to assess outcomes of phone triaging in October. Guidelines for phone triage were formulated with particular regard to what conditions should be seen in EED, treated over the phone or sent straight to outpatients clinic or minor procedures. A prospective phone triage referral and case note audit was then done to assess outcomes after introduction of the guidelines in November. RESULTS: A total of 1700 patients were referred to the eye emergency department, 861 in October and 839 in November. A total of 577 patients were triaged for in-person EED review in November, compared to 692 prior to implementation of guidelines (p < 0.05). The number of patients referred straight to outpatients (p < 0.05) and treated over the phone (p < 0.05) was also significantly increased. Ultimately, the number of conditions unnecessarily triaged to EED, as per the guidelines implemented, was significantly reduced (p < 0.05). CONCLUSION: This audit addressed the need to reduce footfall during the COVID-19 pandemic, identified suitable avenues of referrals for certain conditions, and demonstrated that these guidelines significantly reduced the number of patients presenting to EED with conditions amenable to phone review or clinic follow-up.