Quantitative Gait Feature Assessment on Two-Dimensional Body Axis Projection Planes Converted from Three-Dimensional Coordinates Estimated with a Deep Learning Smartphone App.

To assess pathological gaits quantitatively, three-dimensional coordinates estimated with a deep learning model were converted into body axis plane projections. First, 15 healthy volunteers performed four gait patterns; that is, normal, shuffling, short-stepped, and wide-based gaits, with the Three-Dimensional Pose Tracker for Gait Test (TDPT-GT) application. Second, gaits of 47 patients with idiopathic normal pressure hydrocephalus (iNPH) and 92 healthy elderly individuals in the Takahata cohort were assessed with the TDPT-GT. Two-dimensional relative coordinates were calculated from the three-dimensional coordinates by projecting the sagittal, coronal, and axial planes. Indices of the two-dimensional relative coordinates associated with a pathological gait were comprehensively explored. The candidate indices for the shuffling gait were the angle range of the hip joint < 30° and relative vertical amplitude of the heel < 0.1 on the sagittal projection plane. For the short-stepped gait, the angle range of the knee joint < 45° on the sagittal projection plane was a candidate index. The candidate index for the wide-based gait was the leg outward shift > 0.1 on the axial projection plane. In conclusion, the two-dimensional coordinates on the body axis projection planes calculated from the 3D relative coordinates estimated by the TDPT-GT application enabled the quantification of pathological gait features.

Effects of general anesthesia on behavioral circadian rhythms and clock-gene expression in the suprachiasmatic nucleus in rats.

The suprachiasmatic nucleus (SCN) of the hypothalamus is a nucleus that regulates circadian rhythms through the cyclic expression of clock genes. It has been suggested that circadian-rhythm-related, adverse postoperative events, including sleep disturbances and delirium, are partly caused by anesthesia-induced disruption of clock-gene expression. We examined the effects of multiple general anesthetics on the expression cycle of Period2 (Per2), one of the clock genes that regulate circadian rhythms in the SCN, and on the behavioral rhythms of animals. Rats were treated with sevoflurane, propofol, and dexmedetomidine for 4 h. The expression of Per2 in SCN was analyzed using in situ hybridization, and the behavioral rhythm before and after anesthesia was analyzed. Per2 expression in the SCN decreased significantly immediately after anesthesia in all groups compared with corresponding control groups. However, Per2 returned to normal levels within 24 h, and there was no phase change in the gene expression cycle or behavioral rhythm. This study suggests that acute suppression of Per2 expression may be a general phenomenon induced by general anesthesia, but that the molecular mechanism of the body clock is resilient to disturbances to some extent.

Development of Smartphone Application for Markerless Three-Dimensional Motion Capture Based on Deep Learning Model.

To quantitatively assess pathological gait, we developed a novel smartphone application for full-body human motion tracking in real time from markerless video-based images using a smartphone monocular camera and deep learning. As training data for deep learning, the original three-dimensional (3D) dataset comprising more than 1 million captured images from the 3D motion of 90 humanoid characters and the two-dimensional dataset of COCO 2017 were prepared. The 3D heatmap offset data consisting of 28 × 28 × 28 blocks with three red-green-blue colors at the 24 key points of the entire body motion were learned using the convolutional neural network, modified ResNet34. At each key point, the hottest spot deviating from the center of the cell was learned using the tanh function. Our new iOS application could detect the relative tri-axial coordinates of the 24 whole-body key points centered on the navel in real time without any markers for motion capture. By using the relative coordinates, the 3D angles of the neck, lumbar, bilateral hip, knee, and ankle joints were estimated. Any human motion could be quantitatively and easily assessed using a new smartphone application named Three-Dimensional Pose Tracker for Gait Test (TDPT-GT) without any body markers or multipoint cameras.

Clinical Utility of BDTM mCCDA ClearHT Agar Medium for Campylobacter jejuni.

Campylobacter spp. has been the leading cause of bacterial food poisoning in Japan since 2000. The predominant Campylobacter spp. testing method employs selective medium to isolate Campylobacter spp. In the present study, we evaluated the Campylobacter-isolating capacity and clinical utility of BDTM mCCDA Clear-HT, an agar medium containing a chromogenic substrate, on 230 diarrhea stool samples. After 48 hours incubation, 50 samples (21.7%) were positive with BDTM mCCDA Clear-HT, while 61 samples (26.5%) were positive using modified Skirrow agar medium. In this study, BDTM mCCDA Clear-HT had a lower detection rate of Campylobacter jejuni more than Vitalmedia modified Skirrow agar medium.

Catalytic residues, substrate specificity, and role in carbon starvation of the 2-hydroxy FA dioxygenase Mpo1 in yeast.

The yeast protein Mpo1 belongs to a protein family that is widely conserved in bacteria, fungi, protozoa, and plants, and is the only protein of this family whose function has so far been elucidated. Mpo1 is an Fe2+-dependent dioxygenase that catalyzes the α-oxidation reaction of 2-hydroxy (2-OH) long-chain FAs (LCFAs) produced in the degradation pathway of the long-chain base phytosphingosine. However, several biochemical characteristics of Mpo1, such as its catalytic residues, membrane topology, and substrate specificity, remain unclear. Here, we report that yeast Mpo1 contains two transmembrane domains and that both its N- and C-terminal regions are exposed to the cytosol. Mutational analyses revealed that three histidine residues conserved in the Mpo1 family are especially important for Mpo1 activity, suggesting that they may be responsible for the formation of coordinate bonds with Fe2+ We found that, in addition to activity toward 2-OH LCFAs, Mpo1 also exhibits activity toward 2-OH very-long-chain FAs derived from the FA moiety of sphingolipids. These results indicate that Mpo1 is involved in the metabolism of long-chain to very-long-chain 2-OH FAs produced in different pathways. We noted that the growth of mpo1Δ cells is delayed upon carbon deprivation, suggesting that the Mpo1-mediated conversion of 2-OH FAs to nonhydroxy FAs is important for utilizing 2-OH FAs as a carbon source under carbon starvation. Our findings help to elucidate the as yet unknown functions and activities of other Mpo1 family members.

Psychological health status among former residents of Tomioka, Fukushima Prefecture and their intention to return 8 years after the disaster at Fukushima Daiichi Nuclear Power Plant.

The present study aimed to clarify the psychological status of 766 former residents of Tomioka Town, Fukushima Prefecture, and their intent to return (ITR) 8 years after the disaster at Fukushima Daiichi Nuclear Power Plant. We investigated their ITR home and their perception of the risk of health effects from radiation exposure. We also evaluated rates of post-traumatic stress disorder (PTSD) using a PTSD checklist (PCL-S) and of psychological stress using the patient health questionnaire-9 (PHQ-9). Among the residents, 102 (13%) had returned home (group 1), 214 (28%) were unsure about returning (group 2), and 450 (59%) had decided not to return (group 3). Concern about exposing the next generation to radiation was significantly more prevalent in groups 2 and 3 than in group 1. The frequency of positive PCL-S and PHQ-9 responses was higher in group 2 than in groups 1 and 3. Factors that were independently associated with returning to Tomioka were positive PCL-S (OR, 4.3) and PHQ-9 (OR, 2.2) scores, concerns about consuming locally sourced food, and living with children, and were more prevalent in group 2 than group 1 (reference). Group 2 was more anxious about radiation exposure and health effects, and had higher rates of psychological stress and PTSD. Providing support to such residents through careful risk communication will be required to recover this community after the nuclear disaster.

Mercury speciation in preserved historical sludge: Potential risk from sludge contained within reclaimed land of Minamata Bay, Japan.

In the latter half of the 1950s, a large amount of methylmercury (MeHg) was discharged directly into Minamata Bay, Japan by a chemical factory, resulting in the contamination of the fish and shellfish. Ultimately, an outbreak of MeHg intoxication, called Minamata disease, occurred. From 1977 to 1988, the Kumamoto Prefectural Government dredged and transferred sediments exceeding 25 µg/g of total mercury (THg, dry basis) into a strictly segregated area of the bay near the wastewater outlet, then this area was landfilled. We conducted analyses of the mercury speciation in preserved Minamata Bay sludge samples (collected from inside of the bay prior to the termination of the remediation project; n=4) and recent Minamata Bay sediments (collected outside the dredging area of the bay; n=5) to evaluate the potential risk of the sludge/sediment leakage from the reclaimed land to the Minamata Bay. Median THg (dry basis) concentrations were 241 µg/g for the preserved sludge, 6.1 µg/g for the recent Minamata Bay sediments, and 0.18 µg/g for a single control sample; median MeHg concentrations (percentage of MeHg in THg) were 108 ng/g (0.031%), 3.7 ng/g (0.12%), and 0.71 ng/g (0.41%), respectively. In all the samples, the MeHg% decreased exponentially with increasing THg concentration. The extractability of THg from each sample into seawater was shown to be much lower than that of MeHg. The extracted MeHg was 0.86% for the preserved sludge, 4.57% for the recent Minamata Bay sediments, and 7.89% for the control. The predominant chemical form of mercury in the preserved sludge containing the highest THg concentration was found to be stable ß-mercury sulfide (HgS) based on transmission electron microscopy linked with energy-dispersive X-ray spectroscopy (TEM-EDX) and X-ray absorption fine structure (XAFS) analyses.

Clinical Utility of Pourmedia ViGBS Agar Medium for Group B Streptococcus Screening.

Group B Streptococcus (hereinafter GBS) is the main pathogen in neonatal sepsis and meningitis, accounting for approximately one quarter of the cases. 1) Prevention of infection is therefore crucial. The GBS carriage testing of pregnant women is necessary to prevent infections. In this study, we examined the clinical utility of Pourmedia ViGBS agar medium (Eiken Chemical Co., Ltd.) in GBS screening, using a total of 197 vaginal and urine samples. Of these samples, 32 (16.2%) tested GBS positive with Pourmedia ViGBS agar medium, and 29 (14.7%) tested GBS positive with Nissui separated plate sheep blood agar/Drigalski agar medium (Nissui Pharmaceutical Co., Ltd.). These results indicate the usefulness of Pourmedia ViGBS agar medium as a GBS screening selective agar medium.

[The Evaluation of the MRSA Selective Agar Medium Using Chromogenic Enzyme Substrate from Clinical Specimens].

We evaluated MRSA-CI agar (Kyokuto Pharmaceutical Industrial Co., Ltd.) and BD BBL CHROMagar MRSA II agar (BD Japan) for the detection of Methicillin-resistant Staphylococcus aureus (MRSA). We used 129 specimens in this study. The positive rate of MRSA-CI agar was 19.4% (25/129 samples), whereas BD BBL CHROMagar MRSA II was 17.8% (23/129 samples). It is suggested that MRSA selective agar medium including enzyme substrate compounds is a useful medium to detect MRSA.

Low-frequency coding variants in CETP and CFB are associated with susceptibility of exudative age-related macular degeneration in the Japanese population.

Age-related macular degeneration (AMD) is a major cause of blindness in the elderly. Previous sequencing studies of AMD susceptibility genes have revealed the association of rare coding variants in CFH, CFI, C3 and C9 in European population; however, the impact of rare or low-frequency coding variants on AMD susceptibility in other populations is largely unknown. To identify the role of low-frequency coding variants on exudative AMD susceptibility in a Japanese population, we analysed the association of coding variants of 34 AMD candidate genes in the two-stage design by a multiplex PCR-based target sequencing method. We used a total of 2,886 (1st: 827, 2nd: 2,059) exudative AMD cases including typical AMD, polypoidal choroidal vasculopathy, and retinal angiomatous proliferation and 9,337 (1st: 3,247 2nd: 6,090) controls. Gene-based analysis found a significant association of low-frequency variants (minor allele frequency (MAF) < 0.05) in CETP, C2 and CFB. The association of CETP remained after conditioned with all known genome-wide association study (GWAS) associated variants. In addition, when we included only disruptive variants, enrichment of rare variants (MAF < 0.01) was also observed after conditioned with all GWAS associated variants (P = 1.03 × 10−6, odds ratio (OR) = 2.48). Haplotype and conditional analysis of the C2-CFB-SKIV2L locus showed a low-frequency variant (R74H) in CFB would be individually associated with AMD susceptibility independent of the GWAS associated SNP. These findings highlight the importance of target sequencing to reveal the impact of rare or low-frequency coding variants on disease susceptibility in different ethnic populations.

Posterior Vitreous Detachment as Observed by Wide-Angle OCT Imaging.

PURPOSE: Posterior vitreous detachment (PVD) plays an important role in vitreoretinal interface disorders. Historically, observations of PVD using OCT have been limited to the macular region. The purpose of this study is to image the wide-angle vitreoretinal interface after PVD in normal subjects using montaged OCT images. DESIGN: An observational cross-sectional study. PARTICIPANTS: A total of 144 healthy eyes of 98 normal subjects aged 21 to 95 years (51.4±22.0 [mean ± standard deviation]). METHODS: Montaged images of horizontal and vertical OCT scans through the fovea were obtained in each subject. MAIN OUTCOME MEASURES: Montaged OCT images. RESULTS: By using wide-angle OCT, we imaged the vitreoretinal interface from the macula to the periphery. PVD was classified into 5 stages: stage 0, no PVD (2 eyes, both aged 21 years); stage 1, peripheral PVD limited to paramacular to peripheral zones (88 eyes, mean age 38.9±16.2 years, mean ± standard deviation); stage 2, perifoveal PVD extending to the periphery (12 eyes, mean age 67.9±8.4 years); stage 3, peripapillary PVD with persistent vitreopapillary adhesion alone (7 eyes, mean age 70.9±11.9 years); stage 4, complete PVD (35 eyes, mean age 75.1±10.1 years). All stage 1 PVDs (100%) were observed in the paramacular to peripheral region where the vitreous gel adheres directly to the cortical vitreous and retinal surface. After progression to stage 2 PVD, the area of PVD extends posteriorly to the perifovea and anteriorly to the periphery. Vitreoschisis was observed in 41.2% at PVD initiation (stage 1a). CONCLUSIONS: Whereas prior work suggests that PVD originates in the perifoveal region and after the sixth decade, our observations demonstrate that (1) PVD first appears even in the third decade of life and gradually appears more extensively throughout life; (2) more than 40% of eyes without fundus diseases at their PVD initiation are associated with vitreoschisis; and (3) PVD is first noted primarily in the paramacular-peripheral region where vitreous gel adheres to the retinal surface and is noted to be more extensive in older ages to ultimately involve the fovea.

RETINOCHOROIDAL MORPHOLOGY DESCRIBED BY WIDE-FIELD MONTAGE IMAGING OF SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY.

PURPOSE: To present baseline images of the vitreous, retina, and choroid from the macula to the periphery in normal patients using a novel montaging technique of spectral domain optical coherence tomography. METHODS: Twenty-six normal eyes of 22 healthy volunteers were enrolled in this study. Montaged images of four radial optical coherence tomography scans through the fovea were obtained from each subject. RESULTS: In the macula, there were six identifiable retinal layers as well as four bands in the outer retina. In the periphery, the ganglion cell layer was not identifiable. The external limiting membrane, the second band, and the retinal pigment epithelium were continuously delineated from the macula to the periphery. The third band was not visible in the periphery. CONCLUSION: Spectral domain optical coherence tomography montaged images provide wide-angle images of the vitreous, retina, and choroid, allowing for evaluation of peripheral findings and examination of relationships between peripheral and posterior disease. The maximum scan length achieved here was 36 mm. The scan length is approximately three times than that provided by conventional posterior scanning and is consistent with known dimensions of the eye. This method is achievable with current commercially available devices and may contribute to decision making in clinical practice.

[The development, reliability, and validity of a Japanese version of the MBI-ES].

In this study, we developed a Japanese version of the Maslach Burnout Inventory - Educators Survey (MBI-ES). We also examined the reliability and validity of the scale, based on data from Japanese schoolteachers. Because some items related to depersonalization showed a floor effect, the reliability of the MBI-ES was evaluated using item response theory (IRT), which can evaluate the difficulty of the items. The IRT analysis showed that scores of emotional exhaustion and personal accomplishment had high reliabilities among the wide range of distribution of the latent scores around the means. However, the reliability of the depersonalization items was estimated to be moderate when it was implemented among highly depersonalized teachers, whereas the reliability was lower for relatively healthy teachers. Correlations with the General Health Questionnaire, frequency of emotional labor, and job satisfaction were mostly consistent with previous research and the current theory of burnout, supporting the high validity of the Japanese version of the MBI-ES.

Sternoclavicular Septic Arthritis Caused by Parvimonas micra and Fusobacterium nucleatum Infection with Intra-articular Corticosteroid Administration.

Sternoclavicular septic arthritis is a rare form of septic arthritis that can lead to fatal complications, such as abscess formation and mediastinitis, in the absence of prompt diagnosis and appropriate treatment. A man in his 40s presented with pain in the right sternoclavicular joint area, and after a joint injection of steroids was administered, he was diagnosed with septic sternoclavicular arthritis caused by Parvimonas micra and Fusobacterium nucleatum. Gram staining of a specimen obtained from the abscess formation area led to early suspicion of anaerobic infection, and appropriate antibiotics were administered.

Characteristics of patients with anxiety disorder without selective serotonin reuptake inhibitor prescription over a two-year period of pharmacotherapy.

INTRODUCTION: Pharmacotherapy such as selective serotonin reuptake inhibitors (SSRIs) or serotonin-noradrenaline reuptake inhibitors is recommended for the treatment of anxiety disorders. Although there are patients with persisted symptoms of anxiety disorders who are treated with monotherapy of benzodiazepine anxiolytics without SSRIs, the characteristics of these patients are unclear. In the present study, we investigated the characteristics of patients with persisted symptoms of anxiety disorder without SSRI prescription. METHODS: From a prescription dataset covering 2018 and 2020, the prescriptions of 243 patients with anxiety disorder were analyzed. Patients were classified into two groups: SSRI non-prescription and prescription groups. RESULTS: The SSRI non-prescription group had a higher ratio of females than did the SSRI prescription group (60.1% vs. 44.6%, respectively, p = 3.12 × 10-2 ), but statistically not significant after the Bonferroni correction. No significant differences in age, body mass index, or duration of outpatient visits were found between groups. Among the independent variables, sex (female) was the only variable identified that predicted SSRI non-prescription. CONCLUSION: The present study showed that among patients with anxiety disorders, sex (female) was the only variable that predicted SSRI non-prescription.

[Corneal subepithelial infiltrates that developed following intravitreous injection of bevacizumab].

BACKGROUND: Anti-vascular endothelial growth factor (anti-VEGF) therapies including intravitrous bevacizumab injection (IVB) emerged as an effective treatment for various fundus diseases. Reports of adverse reactions derived from bevacizumab itself are rare. We report a case in which corneal subepithelial infiltrates developed following IVB. CASE: A sixty-six-year-old man presented with visual acuity loss due to cystic macular edema secondary to branch retinal vein occlusion. He developed vascular congestion and subepithelial infiltrates in the peripheral cornea on day 2 following the first IVB. The findings resolved with topical steroid in twelve days. CONCLUSION: A case of subepithelial infiltrate in the peripheral cornea following IVB is reported. Since infiltrates were located along, and associated with the congestion of, the limbal vascular arcade, an innate immune response to bevacizumab may be indicated.

Role of 2-hydroxy acyl-CoA lyase HACL2 in odd-chain fatty acid production via α-oxidation in vivo.

Although most fatty acids (FAs) are even chain, certain tissues, including brain, contain relatively large quantities of odd-chain FAs in their sphingolipids. One of the pathways producing odd-chain FAs is the α-oxidation of 2-hydroxy (2-OH) FAs, where 2-OH acyl-CoA lyases (HACL1 and HACL2) catalyze the key cleavage reaction. However, the contribution of each HACL to odd-chain FA production in vivo remains unknown. Here, we found that HACL2 and HACL1 play major roles in the α-oxidation of 2-OH FAs (especially very-long-chain types) and 3-methyl FAs (other α-oxidation substrates), respectively, using ectopic expression systems of human HACL2 and HACL1 in yeast and analyzing Hacl1 and/or Hacl2 knockout (KO) CHO-K1 cells. We then generated Hacl2 KO mice and measured the quantities of odd-chain and 2-OH lipids (free FAs and sphingolipids [ceramides, sphingomyelins, and monohexosylceramides]) in 17 tissues. We observed fewer odd-chain lipids and more 2-OH lipids in many tissues of Hacl2 KO mice than in wild-type mice, and of these differences the reductions were most prominent for odd-chain monohexosylceramides in the brain and ceramides in the stomach. These results indicate that HACL2-involved α-oxidation of 2-OH FAs is mainly responsible for odd-chain FA production in the brain and stomach.

Montage images of spectral-domain optical coherence tomography in eyes with idiopathic macular holes.

PURPOSE: To describe the morphologic and anatomic relationships at the vitreoretinal interface, from the macula into the periphery, in patients with idiopathic macular hole. Montaged images of posterior and peripheral spectral-domain (SD) optical coherence tomography (OCT) studies were used to describe the anatomic vitreoretinal relationships. DESIGN: Prospective, consecutive, observational case series. PARTICIPANTS: Forty-six eyes of thirty-six consecutive patients with idiopathic macular hole and their fellow eyes. METHODS: Montage images of 4 radial OCT scans (horizontal, vertical, and 2 oblique scans) through the fovea were obtained in each case. MAIN OUTCOME MEASURES: Montage SD OCT images. RESULTS: In fellow eyes, potential precursor changes to macular hole revealed shallow perifoveal vitreous separation that extends peripherally toward the equator. Two distinct configurations were noted at the posterior vitreous face; eyes without holes had a smooth curvature, whereas eyes with holes were more likely to have wavy, folded, or scalloped vitreous surfaces. At the onset of separation, most posterior vitreous cortex had a smooth curvature, but posterior vitreous folds increased with progressive separation. Also notable were zones of double-layered retinoschisis in regions of adherent posterior vitreous. Resulting granular hyperreflection in the peripheral vitreous was detectable in 50% to 60% of stage 1 or 2 holes but in only 33% of stage 3 or 4 holes. CONCLUSIONS: The SD OCT montages taken at serial stages of idiopathic macular holes document distinct configurations of the posterior vitreous face, granular hyperreflection in the peripheral vitreous, and areas of peripheral retinoschisis. Montaging SD OCT images provides novel cross-sectional images of the vitreoretinal interface that may have broader application. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Decreasing Plasma Fibrinogen Levels in the Intensive Care Unit Are Associated with High Mortality Rates In Patients With Sepsis-Induced Coagulopathy.

Plasma fibrinogen levels increase in response to infection, but they could also decrease due to degradation as in severe coagulopathy. We evaluated 60 septic patients with their CRP levels over 5.00 mg/dL. The patients were classified into three groups based on the ratio of the maximum or minimum fibrinogen concentration within day 3 to the initial concentration on day 0: down-, flat, and uptrend groups (n = 15, 30, and 15, respectively). Both down- and flat trend groups showed reduced inflammatory markers on day 3, and the degree of platelet loss (103/µL) and the mortality rate (%) were more remarkable in the downtrend group ( - 108 vs - 42 [p = 0.026] and 46.7 vs 10.0 [p = 0.027]). On day 0, in total 12 and 9 patients were diagnosed with non-overt DIC in the down- and uptrend groups, of which 5 (41.7%) and 1 (11.1%) died within 28 days after admission. In conclusion, decreasing fibrinogen levels in the ICU are associated with high mortality in patients with sepsis followed by decreasing platelet counts, even when they are diagnosed with non-overt DIC.

Mechanistic Insights into the Pathogenesis of Proliferative and Nonproliferative Vitreomacular Traction.

PURPOSE: To describe the vitreoretinal interface in vitreomacular traction (VMT) by using novel optical coherence tomography (OCT) methods; wide-angle montage, and pseudomotion OCT imaging systems. DESIGN: Observational case series. METHODS: Wide-angle montage OCT images of horizontal and vertical scans through the fovea were acquired in 50 eyes of 46 consecutive patients with VMT. Baseline fundus scans were obtained. These were followed by scans acquired with an eye-tracking system performed immediately after vertical and horizontal eye movements. Three scans were then superimposed to compare changes in the contour and position of the posterior vitreous. RESULTS: The subjects were classified as VMT with ("proliferative"; 48.0%) and without ("nonproliferative"; 52.0%) thickened posterior vitreous. Epiretinal membrane was observed in 26.9% of nonproliferative and 95.8% of proliferative VMT eyes (P = 3.6 × 10-7). No eye of proliferative and 57.7% of nonproliferative VMT eyes had wavy contoured posterior vitreous (P = 4.0 × 10-6). None with proliferative VMT, but 91.7% of nonproliferative VMT eyes, showed motion induced changes of posterior vitreous following eye movement (P = 2.0 × 10-8). The posterior vitreous detachment extended beyond the scanned area in 34.6% of nonproliferative and 8.3% of proliferative VMT eyes (P = .040). CONCLUSIONS: By dynamically evaluating the vitreoretinal interface of patients with VMT, the static contraction forces of a thickened posterior vitreous at the macula are implicated in proliferative VMT. This contractile force is not strongly implicated in the majority of VMT eyes with nontaut and more mobile vitreous (nonproliferative VMT). VMT and its associated complications are determined by at least 2 different pathophysiological mechanisms.