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Purpose: To report prevalence and risk factor associations for age-related macular degeneration (AMD) and AMD features from multimodal retinal grading in a multidisciplinary longitudinal population-based study of aging in Northern Ireland., Study Design: Population-based longitudinal cohort study., Methods: Retinal imaging at the Norther Ireland Cohort for the Longitudinal Aging Study health assessment included stereo Colour Fundus Photography (CFP) (Canon CX-1, Tokyo, Japan) and Spectral-Domain Optical Coherence Tomography (SD-OCT) ((Heidelberg Retinal Angopgraph (HRA)+OCT; Heidelberg Engineering, Heidelberg, Germany). Medical history and demographic information was obtained during a home interview. Descriptive statistics were used to describe the prevalence of AMD and individual AMD features. Multiple imputation followed by multiple regression modelling was used to explore risk factor associations including relationships with AMD genetic risk score., Results: Retinal images from 3386 participants were available for analysis. Mean age of the sample was 63.4 (SD 9.01, range: 36-99). Population weighted prevalence of AMD using colour grading in those over 55 years was: no drusen: 6 0.4%; drusen <63 μm: 15.9%; drusen 63-125 µm: 13.7%; drusen >125 µm or pigmentary changes: 8.3%; late AMD: 1.6%. Prevalence of AMD features in those over 55 years was: OCT drusen 27.5%, complete outer retinal pigment epithelium and outer retinal atrophy (cRORA) on OCT was 4.3%, reticular drusen 3.2% and subretinal drusenoid deposits 25.7%. The genetic risk score was significantly associated with drusen and cRORA but less so for SDD alone and non-significant for hyperpigmentation or vitelliform lesions., Conclusions: Multimodal imaging-based classification has provided evidence of some divergence of genetic risk associations between classical drusen and SDD. Our findings support an urgent review of current AMD severity classification systems., Competing Interests: Competing interests: Ruth Hogg: Optos PLC and Novartis; UC: Bayer. These all relate to non-restrictive grants awarded to QUB to support the retinal grading of this study., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY. Published by BMJ.)

Background: Research is needed to identify the unmet disease education and communication needs of people with multiple sclerosis (PwMS) to support informed decision-making, enable self-management and maintain independence for PwMS for as long as possible., Methods: An Expert Steering Group co-developed two studies for PwMS aged 18 years and over: a qualitative, online, patient community activity and a quantitative anonymised online survey. The quantitative survey was conducted in the UK from 12 September 2019 to 18 November 2019 amongst PwMS recruited via the Multiple Sclerosis (MS) Trust newsletter and their closed Facebook group. Questions explored the goals, desires, and knowledge gaps of PwMS. Self-reported data from people with relapsing-remitting multiple sclerosis (RRMS) were collated and reviewed, and discussed by the Steering Group. This paper presents descriptive statistics of the quantitative survey findings., Results: The sample consisted of 117 participants with RRMS. Most respondents (73%) had personal goals related to lifestyle and many (69%) were concerned about maintaining independence. More than half of respondents were worried about planning for the future in relation to income (56%), housing (40%) and most respondents also indicated MS had a negative impact on their lives, including their work life (73%) and social life (69%). Limited occupational support was forthcoming (17% were not provided with any support and only 27% report their work environment being adjusted to suit their needs). The ability to plan for the future and to understand the course of MS were highlighted as key priorities by respondents. A positive trend was observed between those who felt able to plan for the future and their knowledge of MS progression. The proportion of patients who report knowing a 'great deal' about MS prognosis and disability progression was low (16% and 9%, respectively), suggesting an increased role for clinical teams to provide information and education for PwMS. Communication between respondents and their clinical teams highlighted the role of specialist nurses for PwMS to provide holistic, informative support and demonstrated the level of comfort that PwMS have in discussing less clinical topics with these providers., Conclusion: This UK nationwide survey highlighted some of the unmet needs in disease education and communication in a subgroup of UK patients with RRMS, which can impact quality of life. Discussing goals and planning alongside prognosis and disability progression with MS care teams may enable people with RRMS not only to make informed treatment decisions, but also to self-manage and plan for the future, factors which are important to maintain independence., Competing Interests: Declaration of Competing Interest Jordanne Florio-Smith is a current employee of Roche Products Ltd UK and owns stocks and stock options in Roche Mavis Ayer has received consulting fees and speaker fees from Roche, Novartis, Merck, Janssen, Sanofi, Biogen; support for participating in conferences from Roche, Novartis, Merck, Sanofi, Biogen; participated in advisory boards/data safety monitoring boards with Roche, Novartis, Merck, Janssen, Sanofi, Biogen; equipment and/or services from Biogen and Roche; chair of MMSNA Samantha Colhoun has received speaker fees from Novartis Nicola Daykin has received consulting fees from and participated in advisory boards with Roche; speaker fees from Janssen; payment for manuscript writing from Journal of Prescribing Practice; co-chair and policy advisor of MMSNA Brenda Hamill Ayer has received consulting fees and support for participating in conferences from Roche Xierong Liu – none apart from employee of IPSOS MORI Emma Rogers – none apart from ex-employee of IPSOS MORI Alison Thomson has received speaker fees from Novartis; payment for advisory boards from Novartis, Biogen Roberta Pace Balzan is a current employee of Roche Products Ltd UK and owns stocks and stock options in Roche The study and its publication were funded by Roche Products Ltd, and conducted by Ipsos MORI, (Copyright © 2023. Published by Elsevier B.V.)

Background/objectives: This study aims to describe the grading methods and baseline characteristics for UK Biobank (UKBB) participants who underwent retinal imaging in 2009-2010, and to characterise individuals with retinal features suggestive of age-related macular degeneration (AMD), glaucoma and retinopathy., Methods: Non-mydriatic colour fundus photographs and macular optical coherence tomography (OCT) scans were manually graded by Central Administrative Research Facility certified graders and quality assured by clinicians of the Network of Ophthalmic Reading Centres UK. Captured retinal features included those associated with AMD (≥1 drusen, pigmentary changes, geographic atrophy or exudative AMD; either imaging modality), glaucoma (≥0.7 cup-disc ratio, ≥0.2 cup-disc ratio difference between eyes, other abnormal disc features; photographs only) and retinopathy (characteristic features of diabetic retinopathy with or without microaneurysms; either imaging modality). Suspected cases of these conditions were characterised with reference to diagnostic records, physical and biochemical measurements., Results: Among 68,514 UKBB participants who underwent retinal imaging, the mean age was 57.3 years (standard deviation 8.2), 45.7% were men and 90.6% were of White ethnicity. A total of 64,367 participants had gradable colour fundus photographs and 68,281 had gradable OCT scans in at least one eye. Retinal features suggestive of AMD and glaucoma were identified in 15,176 and 2184 participants, of whom 125 (0.8%) and 188 (8.6%), respectively, had a recorded diagnosis. Of 264 participants identified to have retinopathy with microaneurysms, 251 (95.1%) had either diabetes or hypertension., Conclusions: This dataset represents a valuable addition to what is currently available in UKBB, providing important insights to both ocular and systemic health., (© 2022. The Author(s).)

Glaucoma is a progressive eye disease that results in permanent vision loss, and the vertical cup to disc ratio (vCDR) in colour fundus images is essential in glaucoma screening and assessment. Previous fully supervised convolution neural networks segment the optic disc (OD) and optic cup (OC) from color fundus images and then calculate the vCDR offline. However, they rely on a large set of labeled masks for training, which is expensive and time-consuming to acquire. To address this, we propose a weakly and semi-supervised graph-based network that investigates geometric associations and domain knowledge between segmentation probability maps (PM), modified signed distance function representations (mSDF), and boundary region of interest characteristics (B-ROI) in three aspects. Firstly, we propose a novel Dual Adaptive Graph Convolutional Network (DAGCN) to reason the long-range features of the PM and the mSDF w.r.t. the regional uniformity. Secondly, we propose a dual consistency regularization-based semi-supervised learning paradigm. The regional consistency between the PM and the mSDF, and the marginal consistency between the derived B-ROI from each of them boost the proposed model's performance due to the inherent geometric associations. Thirdly, we exploit the task-specific domain knowledge via the oval shapes of OD & OC, where a differentiable vCDR estimating layer is proposed. Furthermore, without additional annotations, the supervision on vCDR serves as weakly-supervisions for segmentation tasks. Experiments on six large-scale datasets demonstrate our model's superior performance on OD & OC segmentation and vCDR estimation. The implementation code has been made available.https://github.com/smallmax00/Dual&#95;Adaptive&#95;Graph&#95;Reasoning.

Purpose: To describe the frequency of long-term morphologic features and their relationships with visual function in participants who exited the Inhibition of VEGF in Age-Related Choroidal Neovascularisation (IVAN; ISRCTN92166560) trial., Design: Multicenter cohort study up to 7 years after enrollment., Participants: Patients enrolled in the IVAN trial, excluding participants who died or withdrew during the trial., Methods: Multimodal fundus images, best-corrected visual acuity (BCVA), and low-luminance visual acuity (LLVA) were obtained for a subset of 199 participants who attended a research visit. Clinical sites (n = 20) also provided all visual acuity and clinical information from usual care records for 532 participants and submitted the most recent color, OCT, and other fundus images for 468 participants to a reading center., Main Outcome Measures: Assessed the following from the most recent images: intralesional macular atrophy (ILMA) within the footprint of the neovascular lesion; hyperreflective material (HRM); intraretinal fluid (IRF); subretinal fluid (SRF); pigment epithelial detachment (PED); and disorganized retinal outer layers (DROLs). Cross-sectional relationships between morphologic features and BCVA/LLVA were estimated., Results: Intralesional macular atrophy was present in 31.8% of the study eyes at IVAN exit (mean follow-up, 1.96 years) and 89.5% at the most recent imaging visit (mean follow-up, 6.18 years). Hyperreflective material, IRF, SRF, PED, and DROLs were present in 78.8%, 47.7%, 7.6%, 94.5%, and 55% of the study eyes, respectively. In the subset with complete imaging data, in eyes without DROL, the BCVA was worst in the thinnest outer fovea tertile (thinnest minus middle and thickest tertiles, -19.7 and -19.5 letters, respectively), whereas in eyes with DROL, the BCVA was worst in the thickest (thinnest and middle tertiles minus thickest, 12.5 and 12.2, respectively). Regression models showed that the presence of ILMA and HRM was independently associated with BCVA (22 letters worse [95% confidence interval {CI}, -11.2 to -32.8; P < 0.001] and 9.8 letters worse [95% CI, -0.1 to -19.4; P = 0.047], respectively). Subretinal fluid and foveal PED were associated with better BCVA (5.9 letters [95% CI, -7.9 to 19.7; P = 0.399] and 6.4 letters [95% CI, -1.1 to 14.0; P = 0.094], respectively). The model with LLVA was similar. A sensitivity analysis involving the entire eligible cohort yielded similar estimates., Conclusions: Macular atrophy and HRM were common after 7 years of follow-up and strongly associated with visual outcomes., (Crown Copyright © 2022. Published by Elsevier Inc. All rights reserved.)

Importance: Eyes with proliferative diabetic retinopathy have a variable response to treatment with panretinal photocoagulation (PRP) or anti-vascular endothelial growth factor agents. The location of neovascularization (NV) is associated with outcomes (eg, patients with disc NV [NVD] have poorer visual prognosis than those with NV elsewhere [NVE])., Objective: To investigate the distribution of NV in patients with proliferative diabetic retinopathy and the topographical response of NV to treatment with aflibercept or PRP., Design, Setting, and Participants: This post hoc analysis of the phase 2b randomized clinical single-masked multicenter noninferiority Clinical Efficacy and Mechanistic Evaluation of Aflibercept for Proliferative Diabetic Retinopathy (CLARITY) trial was conducted from November 1, 2019, to September 1, 2020, among 120 treatment-naive patients with proliferative diabetic retinopathy to evaluate the topography of NVD and NVE in 4 quadrants of the retina on color fundus photography at baseline and at 12 and 52 weeks after treatment., Exposures: In the CLARITY trial, patients were randomized to receive intravitreal aflibercept (2 mg/0.05 mL at baseline, 4 weeks, and 8 weeks, and as needed from 12 weeks onward) or PRP (completed in initial fractionated sessions and then on an as-needed basis when reviewed every 8 weeks)., Main Outcomes and Measures: Main outcomes were per-retinal quadrant frequencies of NV at baseline and frequencies of patterns of regression, recurrence, and new occurrence at 12-week and 52-week unmasked follow-up., Results: The study included 120 treatment-naive patients (75 men; mean [SD] age, 54.8 [14.6] years) with proliferative diabetic retinopathy (there was a 1:1 ratio of eyes to patients). At baseline, NVD with or without NVE was observed in 42 eyes (35.0%), and NVE only was found in 78 eyes (65.0%); NVE had a predilection for the nasal quadrant (64 [53.3%]). Rates of regression with treatment were higher among eyes with NVE (89 of 102 [87.3%]) compared with eyes with NVD (23 of 43 [53.5%]) by 52 weeks, with NVD being more resistant to either treatment with higher rates of persistence than NVE (20 of 39 [51.3%] vs 29 of 100 [29.0%]). Considering NVE, the regression rate in the temporal quadrant was lowest (32 of 42 [76.2%]). Eyes treated with aflibercept showed higher rates of regression of NVE compared with those treated with PRP (50 of 52 [96.2%] vs 39 of 50 [78.0%]; difference, 18.2% [95% CI, 5.5%-30.8%]; P = .01), but no difference was found for NVD (11 of 17 [64.7%] vs 12 of 26 [46.2%]; difference, 18.6% [95% CI, -11.2% to 48.3%]; P = .23)., Conclusions and Relevance: This post hoc analysis found that NVD is less frequent but is associated with more resistance to currently available treatments than NVE. Aflibercept was superior to PRP for treating NVE, but neither treatment was particularly effective against NVD by 52 weeks. Future treatments are needed to better target NVD, which has poorer visual prognosis., Trial Registration: isrctn.org Identifier: ISRCTN32207582.

Purpose: To describe the prevalence of vitreomacular interface (VMI) features and their associated risk factors in the Northern Ireland Cohort for the Longitudinal Study of Ageing (NICOLA) Study., Design: Cross-sectional population-based study., Participants: Noninstitutionalized Northern Irish adults 40 years of age or older., Methods: Using geographic stratification, a representative sample of people in Northern Ireland was invited to participate in the NICOLA Study. SD OCT images of participants were graded for vitreomacular traction (VMT), macular hole (MH), and epiretinal membrane (ERM) according to the International Vitreomacular Traction Study Group. A subsample was graded in more detail to estimate the prevalence of VMA and VMA area detailing size and location of VMA. Descriptive analysis and risk factors for each VMI feature were determined using generalized estimating equations. Results were standardized to the Northern Ireland population census (2011)., Main Outcome Measures: Cohort profile, standardized prevalence, and risk factor associations of each VMI feature., Results: Three thousand three hundred fifty-one NICOLA participants had gradable SD OCT images available for at least 1 eye. The prevalence of VMT was 0.5% (CI, 0.31%-0.70%), that for MH was 0.3% (CI, 0.23%-0.52%), and that for ERM was 7.6% (CI, 7.0%-8.3%). A detailed VMA analysis was performed on a subsample consisting of the first 1481 participants. The prevalence of VMA was 22.6% (CI, 21.1-24.2), and VMA area ranged from 0.25 to 42.7 mm 2 (mean, 12.53 mm 2 ; standard deviation, 6.90 mm 2 ). In multivariate analyses, increased age was associated with an increased odds ratio (OR) of VMT, MH, and ERM. VMA area was positively associated with younger age and normal blood pressure. ERM and MH were present more often in more myopic eyes, associated with an increase in levels of high-density lipoprotein (HDL) cholesterol and triglycerides., Conclusions: The epidemiologic characteristics of VMI features indicated that VMI interactions throughout life are age dependent. Vitreous separation reduced to a greater extent in the horizontal meridians compared with the vertical, differing from previous studies. Future longitudinal studies of the evolution of these VMI changes over time would be of great interest., (Copyright © 2020 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To report on the development and progression of macular atrophy (MA) and its relationship with morphologic and functional measures in study and fellow eyes in the Inhibition of vascular endothelial growth factor (VEGF) in Age-related Choroidal Neovascularisation trial., Design: Reading center analysis of data from a randomized controlled trial., Participants: Participants with previously untreated neovascular age-related macular degeneration (nAMD) in the study eye., Methods: Color, fluorescein angiography (FA) and OCT images acquired at baseline and during the 2-year follow-up were graded systematically for presence of MA. Regression models were constructed to explore relationships between MA and lesion morphology and vision measures (best-corrected distance and near acuity, reading speed and index, contrast sensitivity)., Main Outcome Measures: Primary outcome was development of intralesional MA (≥175 μm greatest linear dimension of choroidal vessels seen on FA and/or color, aided by OCT) lying within the maximum footprint of the neovascular lesion., Results: Study eye data were available for 594 of 610 participants; 57 (9.6%) showed intralesional MA at baseline. Incident intralesional MA occurred in 24.4% by the final visit and extralesional MA in only 1.54%. In fellow eyes, an established nAMD lesion was present at baseline in 248 of whom 42 (16.9%) showed intralesional MA at baseline and 32 (12.9%) developed incident intralesional MA. The odds of incident intralesional MA by final visit were lower in study eyes that had ≥50% classic CNV at baseline (odds ratio [OR], 0.39; 95% confidence interval [CI], 0.19-0.80; P = 0.010), subretinal fluid at final visit (OR, 0.41; 95% CI, 0.25-0.76; P = 0.004), or pigment epithelial detachment at final visit (OR, 0.40; 95% CI, 0.21-0.74; P = 0.004). Secondary analyses of incident or progressed intralesional MA in study eyes supported these findings, with odds increasing if the fellow eye had baseline intralesional MA (OR, 2.43; 95% CI, 1.09-5.44; P = 0.030). No significant associations were observed between development of intralesional MA and any other morphologic or visual function measure., Conclusions: Macular atrophy frequently develops within an nAMD lesion in eyes receiving anti-VEGF therapy over 2 years. No associations between incident MA and drug or treatment frequency or visual function were detected, providing some reassurance to clinicians; however, the longer-term effects remain unknown., (Copyright © 2018 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare diagnostic accuracy of confocal infrared reflectance (IR), with and without optical coherence tomography (OCT), to colour fundus photography (CFP) in the Northern Ireland Cohort for the Longitudinal Study of Ageing (NICOLA) Study., Methods: Cross-sectional observational study of participants in NICOLA. CFP, IR and IR/OCT of 640 eyes were graded for hard, soft and reticular pseudodrusen; geographic atrophy; choroidal neovascularisation; naevus; epiretinal membrane; and haemorrhages. Test characteristics (sensitivity and specificity) for each imaging modality with respect to each retinal feature were calculated., Results: With CFP as the reference standard, sensitivity of IR by itself ranged from 75% for RPD to 93.5% for hard drusen and specificity was above 90% for all features except hard drusen (71.7%). For IR combined with OCT, sensitivity ranged from 80% for choroidal neovascularisation to 96.5% for hard drusen. When IR alone was the reference standard, CFP sensitivity was high for naevi (97.5%) but reduced markedly for epiretinal membrane (48.5%). When the combination of IR and OCT was the reference standard, sensitivity for CFP was least for epiretinal membrane (31.5%), low for geographic atrophy and reticular pseudodrusen (77.8% and 76.2% respectively) and high for all other lesion types., Conclusion: Our findings support the use of confocal IR with OCT as a screening tool for a variety of features of macular disease in community optometric practice., (© 2018 The Authors Ophthalmic & Physiological Optics © 2018 The College of Optometrists.)

The purpose of this investigation was to determine if speech intelligibility improved when divers made specific modifications to their speaking patterns while in a hyperbaric helium-oxygen (heliox) environment. Divers were trained to produce a variety of sentences using speech with three types of alterations: (1) slowed rate, (2) increased loudness, and (3) a combination of slightly slowed rate, a minimal increase in loudness, increased pause time, and greater mouth opening (composite strategy). Both diver and non-diver listeners judged these sentences for intelligibility. In addition, acoustic analysis of the cues for the identification of voicing, place, and manner of articulation was conducted to determine if such cues might become more audible in the speech signal when repair strategies were used. Both perceptual and acoustic results showed the composite method to be the best for natural-sounding, intelligible speech. It had the effect of slowing rate and increasing loudness just enough to increase intelligibility without causing distortion. It was concluded that teaching divers to produce speech using this method would be a worthwhile investment for improving speech intelligibility.

The Speech Intelligibility Index (SII) was measured for Navy divers participating in two saturation deep dives and for a group of nondivers to test different communication systems and their components. These SIIs were validated using the Speech Perception in Noise (SPIN) test and the Griffiths version of the Modified Rhyme Test (GMRT). Our goal was to determine if either of these assessments was sensitive enough to provide an objective measure of speech intelligibility when speech was processed through different helmets and helium speech unscramblers (HSUs). Results indicated that SII values and percent intelligibility decreased incrementally as background noise level increased. SIIs were very reliable across the different groups of subjects indicating that the SII was a strong measurement for predicting speech intelligibility to compare linear system components such as helmets. The SII was not useful in measuring intelligibility through nonlinear devices such as HSUs. The speech intelligibility scores on the GMRT and SPIN tests were useful when the system component being compared had a large measurable difference, such as in helmet type. However, when the differences were more subtle, such as differences in HSUs, neither the SPIN nor the GMRT appeared sensitive enough to make such distinctions. These results have theoretical as well as practical value for measuring the quality and intelligibility of helium speech enhancement systems.

Purpose: Because iatrogenic injury to an underlying inflatable implant may be induced by electrocautery incision of the tunica during tunical release or cylinder reexploration, safe electrocautery guidelines are needed., Materials and Methods: For the in vitro model silicone and polyurethane elastomer lined inflatable penile prosthetic cylinders were used, and cutting and coagulation electrocautery was applied directly on the device, on a tissue-implant interface, and at minimal, partial or full inflation with saline. For the in vivo study 10 patients with underlying inflatable prosthetic cylinders underwent tunical releases for treatment of secondary penile curvature (7) and reexploration for a malpositioned device (3) with a minimum 1 year of followup., Results: In the in vitro study electrocautery injuries either did not occur when applied directly to silicone and polyurethane elastomer lined devices, occurred in both devices in the presence of a tissue-implant interface, occurred in polyurethane elastomer lined devices at a far less thermal energy setting than with silicone, occurred in both implants at lower wattages with increasing saline inflation or did not occur in 100% of polyurethane elastomer lined devices when coagulation electrocautery was less than 65 watts. In the in vivo study, by adhering to the aforementioned principles and using novel surgical techniques, no device malfunctions were created intraoperatively or observed within a mean followup of 22 months., Conclusions: Electrocautery can be used safely to create a tunical incision with any underlying inflatable cylinder. To avoid electrocautery injury, based on the clinical study results in polyurethane elastomer lined devices, one should deflate the cylinder before electrocautery, use coagulation current at 35 watts, apply the electrocautery only to the outer longitudinal tunical layer, bluntly dissect through the inner circular layer, and elevate the tunica, protect the device and incise the tissue under direct vision.

The purpose of this study was to compare the appropriateness and effectiveness of the speech perception in noise (SPIN) test and the Griffiths version of the modified rhyme test (GMRT) in assessing Navy divers' speech understanding using communication systems containing different helium speech unscramblers (HSUs), one of which produces, by subjective observations, more intelligible output than the other. Divers participating in a saturation deep dive and a group of nondivers using digital audio tape recordings of the stimuli used by the divers were tested. Mean percent correct scores on the SPIN and GMRT lists within two listening conditions (taped, topside-diver and live-voice, diver-diver) were almost identical. Listeners scored better on both tests in the topside-diver condition than in the diver-diver condition. The majority of the SPIN errors were on low-predictability items that are void of context. Context clearly played a role in measuring the performance of these subjects, at least for the SPIN test. No significant differences were measured between the two HSUs, although a trend was seen favoring one HSU over the other for the divers. These results have theoretical as well as practical value for measuring the quality and intelligibility of helium speech enhancement systems.

This report describes a case of hereditary persistence of fetal hemoglobin (HPFH) presenting initially as a marginal placental abruption in a primiparous woman at 27 weeks gestation. Persistent but erratic elevation of percent hemoglobin F positive cells, as determined by a modified Kleihauer-Betke method, complicated the remainder of her pregnancy. The clinical impression of placental abruption with possible extension could not be documented by ultrasound or examination of the placenta at delivery. Hemoglobin electrophoresis followed by quantitative fetal hemoglobin first suggested the diagnosis of HPFH, which was confirmed seven months postpartum. Furthermore, the magnitude of percent positive F-cells could be profoundly altered by subtle changes in pH of the acid elution reagent. This case demonstrates that positive acid elution tests for maternal-fetal transfusion may be caused by elevated maternal hemoglobin F. Erratic results, elevated quantitative hemoglobin-F and sensitivity to reagent pH should alert the pathologist to this diagnosis and alter clinical management.

The capillary microhematocrit test is widely used to screen pediatric patients for anemia. Recently, it has been suggested that this method produces spuriously elevated values compared with venous hematocrits measured by a Coulter electronic counter and might consequently fail to detect children who are truly anemic. To address this issue we studied 66 white children 9 months to 14 years of age whose capillary hematocrits were either below, equal to, or one or two points above the lower limit of normal for age. Venous specimens were obtained simultaneously with the capillary sample; hemoglobin, hematocrit, and mean corpuscular volume results were obtained using a Coulter electronic counter. Using published standards of venous hemoglobin, we determined the sensitivity, specificity, and predictive values of the capillary microhematocrit in this population of patients with low or borderline values. Twenty of the 66 patients had venous hemoglobin values less than the lower limit of normal. The sensitivity of the microhematocrit was 90.0%; the specificity was 43.5%. The predictive values for a normal (negative) hematocrit was 90.1%; the predictive value for a low (positive) hematocrit was 40.9%. We conclude that the microhematocrit method using capillary blood will miss very few patients with significantly low venous hemoglobin values and is thus an acceptable screening test for anemia. Because it does not require expensive equipment or special skill to obtain the specimen or perform the test, it is ideal for physicians' offices or nonhospital-based clinics.

Preschool and kindergarten hearing screening programs rely primarily on pure tone audiometry though its reliability with this population has been questioned. Some experts have suggested speech reception testing may be a better indicator of hearing in young children. This study compared screening results on 576 students tested with both pure tone and Verbal Auditory Screening for Children (VASC), a speech reception-based audiometer, and findings of 43 students who could not respond to pure tone testing but did complete VASC. Data indicate VASC was more effective in identifying possible hearing deficits in young children being tested in a screening environment.

Brugia malayi microfilariae of specified ages were obtained from gerbils implanted with fertile adult worms. Such microfilariae were tested for their capacity to infect mosquitoes. A strong age dependence was found for the microfilariae's capacity to: penetrate the mosquito midgut, exsheath in response to 20 mM calcium, and develop to third stage larvae in the mosquito. In addition, differences were found between 2-day-old microfilariae and controls (from larva-infected gerbils) in their reactivities with a series of monoclonal antibodies. Thus, defined immunochemical changes occur in microfilariae as they assume functional maturity.

Factor VIII von Willebrand factor was studied by the immunoperoxidase method in 38 cases of first-trimester therapeutic abortion and two cases of early second-trimester therapeutic abortion. Positive immunostaining was observed in endothelial cells at all gestational ages studied. The findings demonstrate the presence of factor VIII von Willebrand factor in endothelial cells as early as four weeks' gestational age.