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Background and Purpose: Thresholds for abnormal transcranial Doppler cerebrovascular reactivity (CVR) studies are poorly understood, especially for patients with cerebrovascular disease. Using a real‐world cohort with cerebral arterial stenosis, we sought to describe a clinically significant threshold for carbon dioxide reactivity (CO2R) and vasomotor range (VMR). Methods: CVR studies were performed during conditions of breathing room air normally, breathing 8% carbon dioxide air mixture, and hyperventilation. The mean and standard deviation (SD) of CO2R and VMR were calculated for the unaffected side in patients with unilateral stenosis; a deviation of 2 SDs below the mean was chosen as the threshold for abnormal. Receiver operating characteristic (ROC) curves for both sides for patients with unilateral and bilateral stenosis were evaluated for sensitivity (Sn) and specificity (Sp). Results: A total of 133 consecutive CVR studies were performed on 62 patients with stenosis with mean±SD age 55±16 years. Comorbidities included hypertension (60%), diabetes (15%), stroke (40%), and smoking (35%). In patients with unilateral stenosis, mean±SD CO2R for the unaffected side was 1.86±0.53%, defining abnormal CO2R as <0.80%. Mean±SD CO2R for the affected side was 1.27±0.90%. The CO2R threshold predicted abnormal acetazolamide single‐photon emission computed tomography (SPECT) (Sn =.73, Sp =.79), CT/MRI perfusion abnormality (Sn =.42, Sp =.77), infarction on MRI (Sn =.45, Sp =.76), and pressure‐dependent exam (Sn =.50, Sp =.76). For the unaffected side, mean±SD VMR was 39.5±15.8%, defining abnormal VMR as <7.9%. For the affected side, mean±SD VMR was 26.5±17.8%. The VMR threshold predicted abnormal acetazolamide SPECT (Sn =.46, Sp =.94), infarction on MRI (Sn =.27, Sp =.94), and pressure‐dependent exam (Sn =.31, Sp =.90). Conclusions: In patients with multiple vascular risk factors, a reasonable threshold for clinically significant abnormal CO2R is <0.80% and VMR is <7.9%. Noninvasive CVR may aid in diagnosing and risk stratifying patients with stenosis. [ABSTRACT FROM AUTHOR]

This study introduces a hybrid analytical super-resolution (SR) pipeline aimed at enhancing the resolution of medical magnetic resonance imaging (MRI) scans. The primary objective is to overcome the limitations of clinical MRI resolution without the need for additional expensive hardware. The proposed pipeline involves three key steps: pre-processing to re-slice and register the image stacks; SR reconstruction to combine information from three orthogonal image stacks to generate a high-resolution image stack; and post-processing using an artefact reduction convolutional neural network (ARCNN) to reduce the block artefacts introduced during SR reconstruction. The workflow was validated on a dataset of six knee MRIs obtained at high resolution using various sequences. Quantitative analysis of the method revealed promising results, showing an average mean error of 1.40 ± 2.22% in voxel intensities between the SR denoised images and the original high-resolution images. Qualitatively, the method improved out-of-plane resolution while preserving in-plane image quality. The hybrid SR pipeline also displayed robustness across different MRI sequences, demonstrating potential for clinical application in orthopaedics and beyond. Although computationally intensive, this method offers a viable alternative to costly hardware upgrades and holds promise for improving diagnostic accuracy and generating more anatomically accurate models of the human body. [ABSTRACT FROM AUTHOR]

Background: The use of larger femoral heads in total hip replacement (THR) has increased over the last decade. While the relationship between increasing head size and increased stability is well known, the risk of revision with increasing head size remains poorly understood. The aim of this study was to compare the outcome of total hip joint replacement with 32-mm and 36-mm heads. Methods: We carried out a 20-year retrospective analysis of prospective data from the New Zealand Joint Registry (NZJR). All primary total hip replacements registered between January 1999 and December 2018 were included. We compared the rate of revision of 32-mm and 36-mm heads in THR. Sub-group analysis included comparisons of bearing type and all-cause revision. Results: 60,051 primary THRs met our inclusion criteria. The revision rate per 100 component years was significantly higher with a 36-mm head than with a 32-mm head (0.649 vs. 0.534, p < 0.001). Subgroup analysis of bearing type showed no significant differences in revision rates for all combinations of 36-mm heads when compared to 32-mm (p = 0.074–0.92), with the exception of metal-on-metal (MoM); p = 0.038. When MoM was removed there was no significant difference in revision rates per 100 component years between 32-mm and 36-mm heads, 0.528 versus 0.578 (p = 0.099). Conclusions: Increasing head size from 32 mm to 36 mm results in no significant increase in revision in all bearing combinations except MoM. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.apergo.2005.10.003 Byline: Andrew Monk (a), Kate Hone (b), Lorna Lines (b), Alan Dowdall (b), Gordon Baxter (a), Mark Blythe (c), Peter Wright (c) Keywords: Risk management; Risk analysis; Domestic technology; Disabilities; Elderly; Independent living; Dependability Abstract: Information and communication technology applications can help increase the independence and quality of life of older people, or people with disabilities who live in their own homes. A risk management framework is proposed to assist in selecting applications that match the needs and wishes of particular individuals. Risk comprises two components: the likelihood of the occurrence of harm and the consequences of that harm. In the home, the social and psychological harms are as important as the physical ones. The importance of the harm (e.g., injury) is conditioned by its consequences (e.g., distress, costly medical treatment). We identify six generic types of harm (including dependency, loneliness, fear and debt) and four generic consequences (including distress and loss of confidence in ability to live independently). The resultant client-centred framework offers a systematic basis for selecting and evaluating technology for independent living. Author Affiliation: (a) Centre for Usable Home Technology, Department of Psychology, University of York, York YO10 5DD, UK (b) Department of Information Systems and Computing, Brunel University (c) Department of Computer Science, University of York, UK Article History: Received 19 August 2004; Accepted 31 October 2005

Background: The hamstring tendon is frequently used to reconstruct the anterior cruciate ligament (ACL), but there is a lack of consensus on the optimal method of fixation. Registry studies have shown that the type of femoral fixation device can influence the risk of revision ACL reconstruction (ACLR), but it is unclear whether the type of tibial fixation has an effect. In New Zealand, over 95% of hamstring tendon grafts are fixed with an adjustable loop suspensory device on the femoral side, with variable usage between suspensory and interference devices, with or without a sheath, on the tibial side. Purpose: To investigate the association between the type of tibial fixation device and the risk of revision ACLR. Study Design: Cohort Study; Level of evidence, 2. Methods: Prospective data recorded in the New Zealand ACL Registry were analyzed. Only primary ACLRs performed with a hamstring tendon autograft fixed with a suspensory device on the femoral side were included. A Cox regression survival analysis with adjustment for patient factors was performed to analyze the effects of the type of tibial fixation device, the number of graft strands, and graft diameter on the risk of revision. Results: A total of 6145 primary ACLRs performed between 2014 and 2019 were analyzed. A total of 59.6% of hamstring tendon autografts were fixed with a suspensory device on the tibial side (n = 3662), 17.6% with an interference screw with a sheath (n = 1079), and 22.8% with an interference screw without a sheath (n = 1404). When compared with suspensory devices, a higher revision risk was observed when using an interference screw with a sheath (adjusted hazard ratio [HR], 2.05; P =.009) and without a sheath (adjusted HR, 1.81; P =.044). The number of graft strands and a graft diameter of ≥8 mm were associated with the rate of revision on the univariate analysis; however, after adjusting for confounding variables on the multivariate analysis, they did not significantly influence the risk of revision. Conclusion: In this study of hamstring tendon autografts fixed with an adjustable loop suspensory device on the femoral side during primary ACLR, the use of an interference screw, with or without a sheath, on the tibial side resulted in a higher revision rate when compared with a suspensory device. [ABSTRACT FROM AUTHOR]

Background: In primary anterior cruciate ligament (ACL) reconstruction, a bone–patellar tendon–bone (BTB) autograft is associated with lower ipsilateral failure rates. BTB autografts are associated with a higher rate of contralateral ACL injuries, which some clinicians view as a marker of success of the BTB autograft. However, there is a lack of evidence on whether BTB autografts improve the rate of return to activity and sport. Purpose: To compare the rate of return to preinjury activity levels in high-activity patients after ACL reconstruction with BTB autograft or hamstring tendon autograft. Study Design: Cohort study; Level of evidence, 3. Methods: In a high-activity cohort of patients recorded between 2014 and 2018 in the New Zealand ACL Registry, prospectively collected data on preinjury and postoperative Marx activity scores were analyzed. The proportion of patients who returned to their preinjury activity levels at 1- and 2-year follow-up was compared between graft types. Results: Overall, 11.3% (208/1844) of patients returned to their preinjury activity levels at 1-year follow-up, and 15.5% (184/1190) returned at 2-year follow-up. At 1-year follow-up, 17.2% of patients with a BTB autograft returned to their preinjury activity levels compared with 9.3% of patients with a hamstring tendon autograft (adjusted odds ratio, 1.59 [95% CI, 1.16-2.17]; P =.004). At 2-year follow-up, 23.3% of patients with a BTB autograft had returned to their preinjury activity levels compared with 13.3% of patients with a hamstring tendon autograft (adjusted odds ratio, 1.63 [95% CI, 1.14-2.34]; P =.008). Male sex and younger age were associated with a higher rate of return to activity at both follow-up time points. Conclusion: The use of BTB autografts increased the odds of returning to preinjury activity levels at early follow-up. A higher rate of return to activity is a possible explanation for the higher rate of contralateral ACL injuries with the use of BTB autografts. [ABSTRACT FROM AUTHOR]

This article reviews the use of portable microscopes in published science from Antonie van Leeuwenhoek's letters to the Royal Society to a recent paper on the phylogeny of the phorid fly by Hartop et al. [1]. The portability of a pocket microscope is a clear benefit, yet bulky compound microscopes remain the mainstay of field research and diagnosis. There is a growing interest in the impact of climate change, which drives researchers to investigate the smallest, most fragile life in remote places such as Antarctica, Mount Everest, and the Amazon Rainforest. Are pocket microscopes ready to produce publication-standard images? [ABSTRACT FROM AUTHOR]

The article focuses on the use of portable microscopes in aquaculture to enhance productivity and sustainability by enabling rapid diagnosis of diseases and parasites in fish farms. Topics include the increasing importance of fish farming in meeting global food demand, the need for quick and efficient disease detection in aquaculture, and the innovative features of the new generation of pocket-sized digital microscopes.

BACKGROUND AND PURPOSE: Although transcranial Doppler detects microembolic signals (MES) in numerous settings, the practical significance of such findings remains unclear. METHODS: Clinical information from ischemic stroke or transient ischemic attack patients (n = 248) who underwent embolic monitoring from January 2015 to December 2018 was obtained. RESULTS: MES were found in 15% of studies and ischemic recurrence was seen in 11% of patients (over 7 ± 6 days). Patients with MES had more lacunes than those without MES (1 ± 3 vs. 1 ± 2, P =.016), were more likely to have ischemic recurrence (37% vs. 6%, P <.001), undergo a future revascularization procedure (26% vs. 10%, P =.005), have a longer length of stay (9 vs. 4 days, P =.043), and have worse functional disability at discharge (modified Rankin Scale 3‐6, 66% vs. 34%, P <.001). After controlling for several relevant cofactors, patients with MES were more likely to have ischemic recurrence (HR 4.90, 95% CI 2.16‐11.09, P <.001), worse functional disability (OR 3.31, 95% CI 1.22‐8.99, P =.019), and longer length of stays (β =.202, P <.001). CONCLUSIONS: MES may help to risk stratify patients as their presence is associated with ischemic recurrence and worse outcomes. [ABSTRACT FROM AUTHOR]