Cerebral malaria: insight into pathology from optical coherence tomography.

We aimed to investigate structural retinal changes in malarial retinopathy (MR) using hand-held optical coherence tomography (HH-OCT) to assess its diagnostic potential. Children with MR (n = 43) underwent ophthalmoscopy, fluorescein angiography and HH-OCT during admission, 1-month (n = 31) and 1-year (n = 8) post-discharge. Controls were comatose patients without malaria (n = 6) and age/sex-matched healthy children (n = 43). OCT changes and retinal layer thicknesses were compared. On HH-OCT, hyper-reflective areas (HRAs) were seen in the inner retina of 81% of MR patients, corresponding to ischaemic retinal whitening on fundus photography. Cotton wool spots were present in 37% and abnormal hyper-reflective dots, co-localized to capillary plexus, in 93%. Hyper-reflective vessel walls were present in 84%, and intra-retinal cysts in 9%. Vascular changes and cysts resolved within 48 h. HRAs developed into retinal thinning at 1 month (p = 0.027) which was more pronounced after 1 year (p = 0.009). Ischaemic retinal whitening is located within inner retinal layers, distinguishing it from cotton wool spots. Vascular hyper-reflectivity may represent the sequestration of parasitized erythrocytes in vessels, a key CM feature. The mechanisms of post-ischemic retinal atrophy and cerebral atrophy with cognitive impairment may be similar in CM survivors. HH-OCT has the potential for monitoring patients, treatment response and predicting neurological deficits.

Economic modelling of immediately sequential bilateral cataract surgery (ISBCS) in the National Health Service based on possible improvements in surgical efficiency.

OBJECTIVE: To test a hypothesis that operating room (OR) productivity in the National Health Service (NHS) can be improved with the introduction of immediately sequential bilateral cataract surgery (ISBCS). METHODS AND ANALYSIS: Previously published time and motion data of 140 unilateral cataract surgeries conducted at five different NHS locations were reanalysed to construct a hypothetical model where only ISBCS (±one unilateral case) were conducted while maintaining time durations of all key tasks previously studied. Possible time efficiency savings were calculated for the ISBCS model and percentage increases in numbers of eyes operated per 4-hour theatre session calculated. Gains in efficiency were correlated with factors from the baseline data to predict which settings could improve efficiency most by undertaking ISBCS. RESULTS: Based on remodelling our time and motion study (TMS) data as hypothetical ISBCS cases, we could expect a mean 16% reduction (range 9.8%-17.8%) in the time taken for two cataract operations, translating into a mean 54% improvement (range 38%-67%) in number of cases currently performed per list and an 18% improvement (range 9%-28%) even if the number of unilateral cases per list had been fully maximised. An average number of four ISBCS cases per list (range 3-6) were required to achieve sufficient time savings to allow an extra unilateral surgery to be conducted. CONCLUSION: The introduction of routine ISBCS has the potential to improve the productivity of cataract surgery within the NHS, with efficiencies being possible in both high-volume and low-volume surgical models.

Cataract surgery and dry eye disease: A review.

AIM: To review published literature concerning cataract surgery and dry eye disease (DED). METHODS: A search was undertaken using the following: PubMed (all years), Web of Science (all years), Ovid MEDLINE(R) (1946 to 12 December 2019), Ovid MEDLINE(R) Daily Update 10 December 2019, MEDLINE and MEDLINE non-indexed items, Embase (1974-2019, week 49), Ovid MEDLINE (R) and Epub Ahead of Print, In-Process and Other Non-Indexed Citations and Daily (1946 to 12 December 2019), CENTRAL (including Cochrane Eyes and Vision Trials Register; Cochrane Library: Issue 12 of 12 December 2019), metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrial.gov) and WHO International Clinical Trials Registry Platform (www.who.int/ictrp/search/en). Search terms included 'cataract surgery', 'phacoemulsification' and 'cataract extraction', combined with 'dry eyes' and 'ocular surface'. Relevant in-article references not returned in our searches were also considered. RESULTS: Publications identified included systematic reviews, meta-analysis, randomized controlled trials, cohort studies, case series and laboratory-based studies. Published data highlighting the burden of DED both prior and following cataract surgery were reviewed as well as studies highlighting the effects of cataract surgery on the ocular surface, intra-operative measures to reduce deleterious effects on the ocular surface and current evidence on the management options of post-operative DED. CONCLUSIONS: DED is common and can be exacerbated by cataract surgery. Ophthalmologists need to assess for pre-existing DED and instigate treatment before surgery; be aware of reduced accuracy of measurements for surgical planning in the presence of DED; limit intra-operative surgical factors damaging to the ocular surface; and consider management to reduce DED post-operatively.

Acceptability of immediate sequential bilateral cataract surgery (ISBCS) in a public health care setting before and after COVID-19: a prospective patient questionnaire survey.

OBJECTIVE: To ascertain patient acceptance of immediate sequential bilateral cataract surgery (ISBCS) in the National Health Service (NHS). METHODS: A survey was devised using a 5-point Likert scale for questions related to ISBCS, which patients undertook during their cataract outpatient appointment pre-COVID-19 lockdown and by telephone during the lockdown. RESULTS: Questionnaires were completed for 267 patients. Most respondents were aged over 71 (51%) and were female individuals (60%). Forty-five per cent agreed/strongly agreed with opting for ISBCS. A positive correlation was identified between opting for ISBCS and convenience to the patient (r=0.76, p<0.01) and family/carer/partner (r=0.71, p<0.01) and wanting to limit numbers of hospital visits (r=0.57, p<0.01). Fifty per cent agreed/strongly agreed that they were worried about the risk of simultaneous bilateral ocular complications, with this correlating with being less likely to opt for ISBCS (r=-0.49, p<0.01) and being scared of ISBCS (r=0.67, p<0.01). During COVID-19 lockdown, patients were less likely to want to minimise the time taken off work (p<0.05) and less intolerant of a prolonged hospital visit (p<0.05). Only 23% of respondents agreed/strongly agreed that they had familiarity with ISBCS. CONCLUSIONS: ISBCS was acceptable to 45% of our sampled population, suggesting limited routine implementation in the NHS is possible. Convenience and reduction in hospital visits appeared to contribute to this acceptance. Half of the patients expressed concern regarding bilateral complications and such concerns need addressing. Some attitudes did appear to change during the COVID-19 lockdown period. The familiarity of the concept of ISBCS is low suggesting the need for patient education.

Cardiac arrest following paracetamol overdose complicated by hypokalaemia.

We present a case of paracetamol overdose in a 34-year-old female with a history of depression and alcoholism. Following treatment with N-acetylcysteine (Parvolex®) our patient developed ventricular tachycardia resulting in cardiac arrest from which she was successfully resuscitated. Subsequent ECG demonstrated prolongation of the QTc interval and repeat blood tests revealed a significant fall in serum potassium from 4.2mmol/l on admission to 2.2mmol/l. The possible mechanisms contributing to the development of hypokalaemia after overdose with paracetamol are discussed. The existing literature relating to paracetamol-induced hypokalaemia is briefly reviewed.