Acquired Aquagenic Syringeal Keratoderma Following COVID-19 Infection.

Aquagenic syringeal keratoderma (ASK), rare in males, is characterized by the rapid onset of edematous palmar wrinkling with small white papules after brief contact with water or sweat. A 24-year-old atopic male presented with a 2-week subacute history of bilateral palmar edema with whitish-colored papules after exposure to water, 3 months after having had COVID-19 infection treated with a full course of ritonavir-boosted nirmatrelvir (PAXLOVIDTM). He had received 3 COVID-19 vaccines (Pfizer, New York, NY) about 12 months prior. Workup was negative. Initial spontaneous near-resolution 2 months after onset was temporary, with recurrence 1 month later. Treatment with 12% topical aluminum chloride was ineffective. Botulinum toxin injection to both palms led to resolution of symptoms that has been sustained for 7 months. The association between atopy and ASK remains weak. We present a case of new-onset ASK in an adult male 3 months following COVID-19 infection without a history of excessive handwashing. Our patient may have had a predisposition to recurrent ASK due to his history of atopy including atopic dermatitis and food allergy anaphylaxis combined with prior COVID-19 infection. It is possible that ASK is a novel manifestation of post-acute sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (PASC) infection or long COVID.

Longitudinal Retinal and Choroidal Image Analysis in a Set of Monozygotic Twins.

We analyzed multimodal retinal and choroidal imaging, including optical coherence tomography (OCT) and OCT angiography (OCTA), to assess differences and characterize variations in the retinal and choroidal structure and microvasculature between healthy monozygotic twins without ocular or systemic pathology over a five-year period. Retinal imaging of both subjects revealed normal age-related changes. There was up to an 11% difference in OCT and OCTA variables within the subjects, both at baseline and at five years, and there was up to an 18% difference in OCT and OCTA parameters between the subjects for both time points. Larger changes in subfoveal choroidal thickness and foveal avascular zone area were observed. Our observations suggest that the parafoveal superficial capillary plexus, choroidal vascularity index, central subfield thickness, retinal nerve fiber layer thickness, and ganglion cell-inner plexiform layer thickness may be more heavily influenced by genetic, rather than environmental, factors. In contrast, subfoveal choroidal thickness and the foveal avascular zone area may be more heavily influenced by environmental factors. The environmental impact on retinal and choroidal structure and microvasculature is increasingly important to characterize, as such imaging parameters are being explored as potential biomarkers of systemic disease. These differences, as seen in these identical twin subjects, may be important considerations in supporting the security of biometric identifiers.

Late-week Multilevel Anterior Cervical Discectomy and Fusion Associated with Increased Length of Stay.

STUDY DESIGN: Retrospective analysis of clinical data from a single institution. OBJECTIVE: To assess the day of surgery during the week as a possible predictor of length of stay (LOS) following anterior cervical discectomy and fusion (ACDF). SUMMARY OF BACKGROUND DATA: Surgeries later in the week may result in longer LOS and higher costs for joint arthroplasty, yet this is unclear following spine surgery. Procedures performed later in the week may lead to weekend admissions when there are limited services that may contribute to an extended LOS. We attempt to identify associations between day of surgery and LOS, readmission, and complications following single- and multilevel ACDF. MATERIALS AND METHODS: Patients at a single institution undergoing ACDF by 7 primary surgeons in both orthopedic and neurosurgery spine departments between 2015 and 2019 were retrospectively reviewed. Patients were stratified by surgery day at either the beginning (Monday/Tuesday) or end (Thursday/Friday) of the week and by single- or multilevel ACDF. Surgery for trauma, infections, adjacent level disease, or revision were excluded. Patient demographics, Charlson Comorbidity Index (CCI), LOS, postoperative complications, and readmission rates were assessed. RESULTS: Six hundred fifty-two patients underwent ACDF. For single-level ACDF, 222 were reviewed, with 112 having surgery at the beginning and 110 at the end of the week. For multilevel ACDF, 431 were reviewed, with 192 having surgery at the beginning and 239 at the end of the week. No differences in pre- or postoperative variables were determined for single-level ACDF. Despite no differences in pre-operative variables, CCI, operative duration, or number of levels, late-week multilevel ACDF had longer average LOS (2.8±3.0 days) compared to early-week surgery (2.0±2.0 days) (P=0.018). CONCLUSIONS: Late-week multilevel ACDF was associated with an increased LOS, as it may prove beneficial to surgical planning. This conflicts with previous reports that day of week was not associated with LOS following ACDF. LEVEL OF EVIDENCE: III.

The next generation of healthcare ecosystem in the metaverse.

The Metaverse has gained wide attention for being the application interface for the next generation of Internet. The potential of the Metaverse is growing, as Web 3·0 development and adoption continues to advance medicine and healthcare. We define the next generation of interoperable healthcare ecosystem in the Metaverse. We examine the existing literature regarding the Metaverse, explain the technology framework to deliver an immersive experience, along with a technical comparison of legacy and novel Metaverse platforms that are publicly released and in active use. The potential applications of different features of the Metaverse, including avatar-based meetings, immersive simulations, and social interactions are examined with different roles from patients to healthcare providers and healthcare organizations. Present challenges in the development of the Metaverse healthcare ecosystem are discussed, along with potential solutions including capabilities requiring technological innovation, use cases requiring regulatory supervision, and sound governance. This proposed concept and framework of the Metaverse could potentially redefine the traditional healthcare system and enhance digital transformation in healthcare. Similar to AI technology at the beginning of this decade, real-world development and implementation of these capabilities are relatively nascent. Further pragmatic research is needed for the development of an interoperable healthcare ecosystem in the Metaverse.

Knee Injury and Osteoarthritis Outcome Score Trajectories After Primary Total Knee Arthroplasty in United States Veterans.

INTRODUCTION: The volume of total knee arthroplasty (TKA) procedures continues to increase, including among United States (US) veterans, but there is little data characterizing recovery using validated knee-related questionnaires. METHODS: In this prospective cohort study, we sought to establish the feasibility of longitudinal characterization of recovery after TKA using the validated Knee Injury and Osteoarthritis Outcome Score (KOOS), specifically focusing on two of the KOOS subscales (pain and quality of life (QOL)). We solicited participants who agreed to fill out these knee-related questionnaires preoperatively and 3, 6, and 12 months after discharge following unilateral TKA within the Durham Veterans Affairs Health Care System. We examined rates of prospective completion of the KOOS and face validity of scores at each study time point. We transformed and reported scores on the 0-100 scale, with zero representing significant knee pain or poor QOL and 100 representing no knee pain or good QOL. RESULTS: Of 200 US veterans presenting between May 2017 and 2018, 21 (10.5%) agreed to participate by filling out the KOOS questionnaire longitudinally from before surgery until one year after discharge. All 21 (100%) participants were male and completed the two KOOS subscale questions (pain and QOL) preoperatively. Of those, 16 (76.2%) also completed KOOS at 3 months, 16 (76.2%) at 6 months, and seven (33.3%) at 12 months. Compared to mean preoperative values (pain: 33.47 + 6.78, QOL: 11.91 + 4.99), the KOOS subscale scores had significantly improved by 6 months after TKA (pain: 74.41 + 10.72, QOL: 49.61 + 13.25) but plateaued at 12 months (pain: 74.60 + 20.80, QOL: 50.89 + 20.61). The magnitude of improvement in absolute scores, pain and QOL, was similar and significant at 12 months compared to preoperative values with an increase of 41.13 (p=0.007) and 38.98 (p=0.009), respectively. CONCLUSION: Primary TKA in US veterans with advanced osteoarthritis may lead to improved patient-reported KOOS pain and QOL subscale measures at 12 months compared to preoperative scores, with the majority of improvement occurring by 6 months. Only one in ten US veterans approached preoperatively agreed to complete the validated knee-related outcomes questionnaire prior to undergoing TKA. About three-quarters of those veterans also completed it both three and six months after discharge. Collected KOOS subscale scores demonstrated face validity and showed substantial improvement in pain and QOL over the six-month postoperative period. Only one in three veterans who completed the KOOS questionnaire preoperatively also completed it at 12 months, but this does not support the feasibility of follow-up assessments beyond 6 months. To better understand longitudinal pain and QOL trajectories in US veterans undergoing primary TKA for advanced osteoarthritis and to improve study participation, additional research using the KOOS questionnaire may add further insights into this underreported population.

Identifying Peripapillary Radial Capillary Plexus Alterations in Parkinson's Disease Using OCT Angiography.

PURPOSE: To compare radial peripapillary capillary (RPC) plexus vascular parameters and retinal nerve fiber layer (RNFL) thickness between those with Parkinson's disease (PD) and controls. DESIGN: Prospective, cross-sectional study. PARTICIPANTS: A total of 151 eyes of 81 PD participants and 514 eyes of 266 controls. METHODS: Participants underwent OCT angiography (OCTA) imaging using the Zeiss Cirrus HD-5000 AngioPlex (Carl Zeiss AG). Capillary perfusion density (CPD) and capillary flux index (CFI) were assessed using a 4.5 × 4.5-mm peripapillary scan, and RNFL thickness was assessed using a 200 × 200-µm optic nerve cube OCT scan. Hoehn and Yahr clinical staging for PD was determined by an experienced movement disorders specialist. Generalized estimating equations adjusted for age and sex were used for analysis. MAIN OUTCOME MEASURES: Differences in RNFL thickness, CPD, and CFI as assessed using multivariable generalized estimating equations between individuals with PD and controls. RESULTS: After adjustment for age and sex, average CPD (0.446% ± 0.018% vs. 0.439% ± 0.017%, P < 0.001) and CFI (0.434 ± 0.031 vs. 0.426 ± 0.036, P = 0.008) were significantly higher in PD eyes. Average RNFL thickness was similar between groups (PD 89.71 ± 10.45 µm vs. control 88.20 ± 10.33 µm, P = 0.19). Significant correlations between Hoehn and Yahr stage and OCTA parameters were not observed. The OCTA parameters were not significantly different between eyes of the same patient. CONCLUSIONS: Increased peripapillary microvascular density and flux were detected in a large cohort of individuals with PD compared with controls after adjusting for age and sex; however, RNFL thickness was similar between groups. Peripapillary OCTA parameters may not correlate with the severity of PD. OCTA may serve as a noninvasive method to identify novel biomarkers for the early diagnosis of PD; as such, this methodology deserves further investigation.

Convolutional neural network to identify symptomatic Alzheimer's disease using multimodal retinal imaging.

BACKGROUND/AIMS: To develop a convolutional neural network (CNN) to detect symptomatic Alzheimer's disease (AD) using a combination of multimodal retinal images and patient data. METHODS: Colour maps of ganglion cell-inner plexiform layer (GC-IPL) thickness, superficial capillary plexus (SCP) optical coherence tomography angiography (OCTA) images, and ultra-widefield (UWF) colour and fundus autofluorescence (FAF) scanning laser ophthalmoscopy images were captured in individuals with AD or healthy cognition. A CNN to predict AD diagnosis was developed using multimodal retinal images, OCT and OCTA quantitative data, and patient data. RESULTS: 284 eyes of 159 subjects (222 eyes from 123 cognitively healthy subjects and 62 eyes from 36 subjects with AD) were used to develop the model. Area under the receiving operating characteristic curve (AUC) values for predicted probability of AD for the independent test set varied by input used: UWF colour AUC 0.450 (95% CI 0.282, 0.592), OCTA SCP 0.582 (95% CI 0.440, 0.724), UWF FAF 0.618 (95% CI 0.462, 0.773), GC-IPL maps 0.809 (95% CI 0.700, 0.919). A model incorporating all images, quantitative data and patient data (AUC 0.836 (CI 0.729, 0.943)) performed similarly to models only incorporating all images (AUC 0.829 (95% CI 0.719, 0.939)). GC-IPL maps, quantitative data and patient data AUC 0.841 (95% CI 0.739, 0.943). CONCLUSION: Our CNN used multimodal retinal images to successfully predict diagnosis of symptomatic AD in an independent test set. GC-IPL maps were the most useful single inputs for prediction. Models including only images performed similarly to models also including quantitative data and patient data.

Assessing the Retinal Microvasculature in Individuals With Early and Late-Onset Alzheimer's Disease.

BACKGROUND AND OBJECTIVE: To evaluate retinal microvascular changes in early and late-onset Alzheimer's disease (AD). PATIENTS AND METHODS: Eighty-six eyes of 50 late-onset AD participants, 27 eyes of 15 early onset AD participants, and 111 eyes of 57 cognitively normal controls were included. Optical coherence tomography angiography (OCTA) vessel density (VD) and perfusion density (PD) in Early Treatment Diabetic Retinopathy Study 3-mm and 6-mm circles and rings were assessed. RESULTS: There was decreased PD in early onset AD 3-mm circle (P = .026) and ring (P = .026) versus controls as well as in late-onset AD 3-mm circle (P = .023) and ring (P = .023) versus controls. There was decreased VD in late-onset AD 3-mm circle (P = .012) and ring (P = .006). No parameters differed between early and late-onset AD (P > .05). CONCLUSIONS: AD eyes exhibited decreased retinal microvascular density compared to controls. Retinal parameters may not differ between early onset AD and late-onset AD after adjusting for age. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:336-344.].

Choroidal Structural Analysis in Alzheimer Disease, Mild Cognitive Impairment, and Cognitively Healthy Controls.

PURPOSE: To assess choroidal structural parameters in symptomatic Alzheimer disease (AD), mild cognitive impairment (MCI), and cognitively healthy control subjects. DESIGN: Prospective cross-sectional study. METHODS: This study took place in an outpatient neurological disorders clinic. Participants included 67 patients (112 eyes) with AD, 74 patients (143 eyes) with MCI, and 137 (248 eyes) control subjects. Subjects with diabetes, glaucoma, or retinal pathology were excluded. High-definition enhanced depth imaging foveal scans were obtained using Zeiss Cirrus HD-5000 AngioPlex. Subfoveal choroidal thickness (SFCT) was measured by 2 masked graders with a third adjudicator. Total choroidal area (TCA), luminal area (LA), and the choroidal vascularity index (CVI) were calculated after image binarization. Association of choroidal parameters with AD, MCI, or control subjects was assessed using multivariable generalized estimating equations, adjusted for age, sex, and visual acuity. RESULTS: After adjustment for age, sex, and visual acuity, TCA was significantly greater in patients with AD (ß = 2.73; p = .001) and MCI (ß = 4.38; p < .001) compared with control subjects. LA was significantly greater in patients with AD (ß = 1.68; p = .001) and MCI (ß = 2.69; p < .001) compared with control subjects, and CVI was significantly lower in patients with MCI (ß = -0.58; p = .002) compared with control subjects. SFCT was similar among patients with AD and MCI and control subjects on multivariable analysis (p > .05). CONCLUSIONS: TCA, LA, and CVI may differ between patients with AD, MCI, and healthy cognition, whereas SFCT may not differ among these groups. TCA, LA, and CVI deserve further study in subjects on the Alzheimer continuum.

Characterization of Retinal Microvascular and Choroidal Structural Changes in Parkinson Disease.

Importance: Noninvasive retinal imaging may detect structural changes associated with Parkinson disease (PD) and may represent a novel biomarker for disease detection. Objective: To characterize alterations in the structure and microvasculature of the retina and choroid in eyes of individuals with PD and compare them with eyes of age- and sex-matched cognitively healthy control individuals using optical coherence tomography (OCT) and OCT angiography (OCTA). Design, Setting, and Participants: This cross-sectional study was conducted at the Duke Neurological Disorders Clinic in Durham, North Carolina. Individuals aged 50 years or older with a diagnosis of PD were eligible for inclusion and underwent an evaluation and diagnosis confirmation before enrollment. Control individuals aged 50 years or older and without subjective cognitive dysfunction, a history of tremor, or evidence of motor dysfunction consistent with parkinsonism were solicited from the clinic or the Duke Alzheimer's Disease Prevention Registry. Individuals with diabetes, glaucoma, retinal pathology, other dementias, and corrected Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity worse than 20/40 Snellen were excluded. Data were analyzed between January 1, 2020, and March 30, 2020. Exposures: All participants underwent OCT and OCTA imaging. Main Outcomes and Measures: Generalized estimating equation analysis was used to characterize the association between imaging parameters and PD diagnosis. Superficial capillary plexus vessel density (VD) and perfusion density (PFD) were assessed within the ETDRS 6 × 6-mm circle, 6 × 6-mm inner ring, and 6 × 6-mm outer ring, as was the foveal avascular zone area. Peripapillary retinal nerve fiber layer thickness, macular ganglion cell-inner plexiform layer thickness, central subfield thickness, subfoveal choroidal thickness, total choroidal area, luminal area, and choroidal vascularity index (CVI) were measured. Results: A total of 124 eyes of 69 participants with PD (39 men [56.5%]; mean [SD] age, 71.7 [7.0] years) and 248 eyes of 137 control participants (77 men [56.2%]; mean [SD] age, 70.9 [6.7] years) were analyzed. In the 6 × 6-mm ETDRS circle, VD (ß coefficient = 0.37; 95% CI, 0.04-0.71; P = .03) and PFD (ß coefficient = 0.009; 95% CI, 0.0003-0.018; P = .04) were lower in eyes of participants with PD. In the inner ring of the 6 × 6-mm ETDRS circle, VD (ß coefficient = 0.61; 95% CI, 0.20-1.02; P = .003) and PFD (ß coefficient = 0.015; 95% CI, 0.005-0.026; P = .004) were lower in eyes of participants with PD. Total choroidal area (ß coefficient = -1.74 units2; 95% CI, -3.12 to -0.37 units2; P = .01) and luminal area (ß coefficient = -1.02 units2; 95% CI, -1.86 to -0.18 units2; P = .02) were greater, but CVI was lower (ß coefficient = 0.5%; 95% CI, 0.2%-0.8%; P < .001) in eyes of individuals with PD. Conclusions and Relevance: This study found that individuals with PD had decreased retinal VD and PFD as well as choroidal structural changes compared with age- and sex-matched control participants. Given the observed population differences in these noninvasive retinal biomarkers, further research into their clinical utility in PD is needed.

Association of OCT Angiography Parameters With Age in Cognitively Healthy Older Adults.

BACKGROUND AND OBJECTIVE: To evaluate the association of changes in retinal anatomy and microvasculature with age and sex in cognitively healthy older adults. PATIENTS AND METHODS: Cross-sectional study of cognitively healthy subjects aged 50 years and older who underwent optical coherence tomography angiography (OCTA) to estimate the association between age and sex with ganglion cell layer-inner plexiform layer (GC-IPL); central subfield thickness (CST); subfoveal choroidal thickness (CT); foveal avascular zone (FAZ) size; and superficial (SCP), deep (DCP), and whole capillary plexus (WCP) vessel density (VD) and perfusion density (PD) measured in the ETDRS 3-mm and 6-mm circle and rings. RESULTS: Among 141 older adults (72.9% female; median age: 69 years), 282 eyes were imaged. Females had a greater CT, GC-IPL thickness, and FAZ size and a lower CST than males. After controlling for sex, both CT (P = .001) and GC-IPL thickness (P < .001) decreased with age, whereas FAZ size and CST did not. There was a reduction in VD and PD in SCP, DCP, and WCP with age in the 3-mm circle, 3-mm ring, and 6-mm circle (all P < .05). CONCLUSIONS: There is a significant reduction in both VD and PD, as well as decreased choroidal and GC-IPL thickness associated with aging, even beyond the fifth decade, in cognitively healthy adults. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:706-714.].

Correlation of OCTA and Volumetric MRI in Mild Cognitive Impairment and Alzheimer's Disease.

BACKGROUD AND OBJECTIVE: To evaluate the relationship between retinal microvascular parameters on optical coherence tomography angiography (OCTA) and neurodegenerative changes assessed by measurement of brain volume on volumetric magnetic resonance imaging (MRI) in Alzheimer's disease (AD) and mild cognitive impairment (MCI). PATIENTS AND METHODS: Sixteen subjects with AD and MCI underwent OCTA imaging (3 mm × 3 mm and 6 mm × 6 mm scans) and volumetric brain MRI imaging with automated volumetric segmentation and quantification. Spearman's correlation (ρ) was performed between forebrain parenchyma, cortical gray matter, inferolateral ventricle (ILV), lateral ventricle (LV), and hippocampus (HP) MRI volumes and vessel density (VD), along with perfusion density (PD) for the 6-mm circle, 6-mm ring, 3-mm circle, and 3-mm ring Early Treatment Diabetic Retinopathy Study regions of the superficial capillary plexus. RESULTS: Thirty eyes of 16 patients (seven MCI and nine AD) with good-quality OCTA images were analyzed. ILV volume inversely correlated with the VD in the 6-mm circle (ρ = -0 .565, P = .028) and 3-mm ring (ρ = -0.569, P = .027) and PD in the 3-mm ring (ρ = -0.605, P = .0169). Forebrain, cortical gray matter, LV, and HP volumes did not significantly correlate with either VD or PD (P > .05). CONCLUSIONS: In this pilot investigation, the authors found a significant correlation between reduction in the superficial capillary plexus VD and PD on OCTA and expansion of the ILV in MCI and AD. This relationship between the retinal microvasculature and cerebral volumetric changes deserves further investigation. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:709-718.].

Retinal Microvascular and Neurodegenerative Changes in Alzheimer's Disease and Mild Cognitive Impairment Compared with Control Participants.

PURPOSE: Evaluate and compare the retinal microvasculature in the superficial capillary plexus (SCP) in Alzheimer's disease (AD), mild cognitive impairment (MCI), and cognitively intact controls using OCT angiography. OCT parameters were also compared. DESIGN: Cross-sectional study. PARTICIPANTS: Seventy eyes from 39 AD participants, 72 eyes from 37 MCI participants, and 254 eyes from 133 control participants were enrolled. METHODS: Participants were imaged using Zeiss Cirrus HD-5000 with AngioPlex (Carl Zeiss Meditec, Dublin, CA) and underwent cognitive evaluation with Mini-Mental State Examination. MAIN OUTCOME MEASURES: Vessel density (VD) and perfusion density (PD) in the SCP within the Early Treatment Diabetic Retinopathy Study 6-mm circle, 3-mm circle, and 3-mm ring were compared between groups. Foveal avascular zone (FAZ) area, central subfield thickness (CST), macular ganglion cell-inner plexiform layer (GC-IPL) thickness, and peripapillary retinal nerve fiber layer (RNFL) thickness were also compared. RESULTS: Alzheimer's participants showed significantly decreased SCP VD and PD in the 3-mm ring (P = 0.001 and P = 0.002, respectively) and 3-mm circle (P = 0.003 and P = 0.004, respectively) and decreased SCP VD in the 6-mm circle (P = 0.047) compared with MCI and significantly decreased SCP VD and PD in the 3-mm ring (P = 0.008 and P = 0.004, respectively) and 3-mm circle (P = 0.015 and P = 0.009, respectively) and SCP PD in the 6-mm circle (P = 0.033) when compared with cognitively intact controls. There was no difference in SCP VD or PD between MCI and controls (P > 0.05). FAZ area and CST did not differ significantly between groups (P > 0.05). Alzheimer's participants showed significantly decreased GC-IPL thickness over the inferior (P = 0.032) and inferonasal (P = 0.025) sectors compared with MCI and significantly decreased GC-IPL thickness over the entire (P = 0.012), superonasal (P = 0.041), inferior (P = 0.004), and inferonasal (P = 0.006) sectors compared to controls. MCI participants showed significantly decreased temporal RNFL thickness (P = 0.04) compared with controls. CONCLUSIONS: Alzheimer's participants showed significantly reduced macular VD, PD, and GC-IPL thickness compared with MCI and controls. Changes in the retinal microvasculature may mirror small vessel cerebrovascular changes in AD.

Acceptable Functional Outcomes and Patient Satisfaction Following Total Knee Arthroplasty in Asians with Severe Knee Stiffness: A Matched Analysis.

BACKGROUND: This study evaluated outcomes following total knee arthroplasty for severely stiff knees in Asians. METHODS: Registry data of patients undergoing primary total knee arthroplasty between 2004 and 2013 were collected and retrospectively reviewed. Sociodemographic and anthropometric data together with the Oxford Knee Score and the Knee Society Score (Knee Society Knee Score and the Knee Society Function Score) were collected both preoperatively and postoperatively for up to 2 years. Case subjects consisted of patients with a preoperative flexion range of ≤ 20°. Control subjects consisted of patients with a preoperative flexion range of > 90°. Patients were matched for age, sex, and all preoperative scores in a 2:1 fashion. Two-year outcomes and 5-year revision rates were then compared between cases and controls. RESULTS: There were 28 cases and 56 controls. Cases had a significantly lower body mass index than the controls (p = 0.003) and had a longer hospital stay (p < 0.0001). At 2 years, cases had a significantly lower flexion range (p < 0.001) and a lower Knee Society Function Score (p = 0.020) than the controls. Cases had a significantly greater improvement in the flexion range (p < 0.001) postoperatively than controls. The mean change in functional outcomes at 2 years was comparable between the two groups. Seventy-one percent of the cases and 88% of controls were satisfied. There was a significant difference in the 5-year revision rate (10% vs 0%, p = 0.013). More cases were discharged to a rehabilitation facility compared to controls (p = 0.011). There were no differences in inpatient complication rates. CONCLUSIONS: Functional outcomes and patient satisfaction were acceptable following total knee arthroplasty in Asian patients with severe knee stiffness.

Assessment of Differences in Retinal Microvasculature Using OCT Angiography in Alzheimer's Disease: A Twin Discordance Report.

The authors report the optical coherence tomography angiography (OCTA)-based comparative assessment of the retinal microvasculature in a rare pair of 96-year-old female monozygotic twins discordant for Alzheimer's disease (AD). Using automated mapping of the superficial capillary plexus, the authors observed that the twin with advanced AD had a significantly reduced vessel density and a larger foveal avascular zone in the superficial capillary plexus as well as a thinner choroid compared to the twin who was cognitively normal. This unique twin discordance report adds to the evidence supporting the use of retinal microvasculature changes in the superficial capillary plexus on OCTA as a possible noninvasive biomarker for AD. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:440-444.].