Changes in Parameters after High Tibial Osteotomy: Comparison of EOS System and Computed Tomographic Analysis.

Unintended rotation of the distal tibia occurs during medial open-wedge high tibial osteotomy (MOWHTO). Computed tomography (CT) is the standard method of measuring lower limb alignment; however, the new low-dose EOS system allows three-dimensional limb modeling with automated measurements of lower limb alignment. This study investigated the differences between the changes in lower limb alignment profiles obtained using the EOS system and CT in patients who underwent MOWHTO. We investigated whether any factors contributed to the degree of deformation. Thirty patients were prospectively enrolled between October 2019 and February 2023. Changes in femoral and tibial torsion, femorotibial rotation, and posterior tibial slope were measured using pre- and post-MOWHTO CT and EOS images. We found no significant difference in pre- and postoperative tibial torsion or posterior tibial slope between CT and EOS. No variables showed a significant correlation with changes in the tibial torsion or posterior tibial slope. This study confirmed the possibility that the EOS system could replace CT in measuring changes in several parameters pre- and postoperatively. Furthermore, we confirmed that the distal tibia tended to be internally rotated after MOWHTO; however, we found no significantly related parameters related to deformation caused by MOWHTO.

Preoperative embolization of suprasellar hemangioblastoma supplied by artery of foramen rotundum: a case report and review of the literature.

We present the case of 69-year-old woman who underwent preoperative embolization of a suprasellar hemangioblastoma supplied by the artery of foramen rotundum. To our best knowledge, this is the first such report in English. We review the literature focusing on feeding arteries of sellar and suprasellar hemangioblastomas.

Self-evolving vision transformer for chest X-ray diagnosis through knowledge distillation.

Although deep learning-based computer-aided diagnosis systems have recently achieved expert-level performance, developing a robust model requires large, high-quality data with annotations that are expensive to obtain. This situation poses a conundrum that annually-collected chest x-rays cannot be utilized due to the absence of labels, especially in deprived areas. In this study, we present a framework named distillation for self-supervision and self-train learning (DISTL) inspired by the learning process of the radiologists, which can improve the performance of vision transformer simultaneously with self-supervision and self-training through knowledge distillation. In external validation from three hospitals for diagnosis of tuberculosis, pneumothorax, and COVID-19, DISTL offers gradually improved performance as the amount of unlabeled data increase, even better than the fully supervised model with the same amount of labeled data. We additionally show that the model obtained with DISTL is robust to various real-world nuisances, offering better applicability in clinical setting.

Effects of an Eye-Tracking Linkage Attention Training System on Cognitive Function Compared to Conventional Computerized Cognitive Training System in Patients with Stroke.

Objective: The purpose of the study was to investigate the effects of an eye-tracking linkage attention training system on cognitive function compared to a conventional computerized cognitive training system in stroke patients with cognitive impairment. Methods: This retrospective study was enrolled 40 stroke patients who received cognitive rehabilitation. The intervention consisted of 30 sessions and 30 min per session. Before and after the intervention, we assessed cognitive functions by Mini-Mental State Examination (MMSE-K) and activities of daily living by Modified Barthel Index (K-MBI) and administered a computerized neuropsychological test (CNT). Results: In both groups, there were significant improvements in MMSE-K and K-MBI (p < 0.05). In the visual and auditory attention test of the CNT, the eye-tracking linkage attention training group was significantly improved after intervention (p < 0.05). However, there were no significant differences in the conventional computerized cognitive training group. In addition, there were significant improvements in all memory tests of the CNT in the eye-tracking linkage attention training group. However, in the conventional computerized cognitive training group, there were significant improvements in some memory tests of the CNT. Conclusions: The training of poststroke cognitive impairment patients using an eye-tracking linkage attention training system may improve visuospatial attention and may be helpful for the improvement of short-term memory and independent performances in daily life activities.

Multi-task vision transformer using low-level chest X-ray feature corpus for COVID-19 diagnosis and severity quantification.

Developing a robust algorithm to diagnose and quantify the severity of the novel coronavirus disease 2019 (COVID-19) using Chest X-ray (CXR) requires a large number of well-curated COVID-19 datasets, which is difficult to collect under the global COVID-19 pandemic. On the other hand, CXR data with other findings are abundant. This situation is ideally suited for the Vision Transformer (ViT) architecture, where a lot of unlabeled data can be used through structural modeling by the self-attention mechanism. However, the use of existing ViT may not be optimal, as the feature embedding by direct patch flattening or ResNet backbone in the standard ViT is not intended for CXR. To address this problem, here we propose a novel Multi-task ViT that leverages low-level CXR feature corpus obtained from a backbone network that extracts common CXR findings. Specifically, the backbone network is first trained with large public datasets to detect common abnormal findings such as consolidation, opacity, edema, etc. Then, the embedded features from the backbone network are used as corpora for a versatile Transformer model for both the diagnosis and the severity quantification of COVID-19. We evaluate our model on various external test datasets from totally different institutions to evaluate the generalization capability. The experimental results confirm that our model can achieve state-of-the-art performance in both diagnosis and severity quantification tasks with outstanding generalization capability, which are sine qua non of widespread deployment.

T2/FLAIR Hyperintensity in Mesial Temporal Lobe: Challenging Differential Diagnosis.

T2/FLAIR hyperintensity in the mesial temporal lobe is the most common MR finding of herpes simplex encephalitis, but may be observed in other infectious and non-infectious diseases. The former includes herpes human virus 6 encephalitis, Japanese encephalitis, and neurosyphilis, and the latter autoimmune encephalitis, gliomatosis cerebri, bilateral or paradoxical posterior cerebral artery infarction, status epilepticus, and hippocampal sclerosis. Thus, T2/FLAIR hyperintensity in the mesial temporal lobe is not a disease-specific magnetic resonance imaging finding, and these conditions must be differentiated to ensure proper treatment. We review diseases that present with T2/FLAIR hyperintensity in the mesial temporal lobe and provide a helpful flow chart based on clinical and radiologic features.

Impact of Computed Tomography-Quantified Emphysema Score on Clinical Outcome in Patients with COVID-19.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is considered a risk factor for poor outcomes in patients with coronavirus disease 2019 (COVID-19). However, data on the prognostic impact of radiological emphysema extent on patients with COVID-19 are limited. Thus, this study aimed to examine whether computed tomography (CT)-quantified emphysema score is associated with a worse clinical outcome in patients with COVID-19. METHODS: Volumetric quantitative analyses of CT images were performed to obtain emphysema scores in COVID-19 patients admitted to four tertiary referral hospitals in Daegu, South Korea, between February 18 and March 25, 2020. Patients were divided into three groups according to emphysema score (emphysema score ≤1%, 1%< emphysema score ≤5%, and emphysema score >5%). RESULTS: A total of 146 patients with confirmed SARS-CoV-2 infection were included. The median emphysema score was 1.0% (interquartile range, 0.5-1.8%). Eight patients (6%) had a previous COPD diagnosis. Eighty (55%), 55 (38%), and 11 (8%) patients had emphysema scores ≤1%, between 1% and 5%, and >5%, respectively. The number of patients who received oxygen therapy two weeks after admission was significantly higher in the group with emphysema scores >5% than in other groups (p=0.025). The frequency of deaths was three (27%) in the group with emphysema scores >5% and tended to be higher than that in other groups. Multivariate analysis revealed that age, COPD, and serum lactate dehydrogenase levels were associated with a greater risk of in-hospital mortality in patients with COVID-19. CONCLUSION: The current study demonstrated that patients with CT-quantified emphysema scores >5% tended to progress to severe disease over time; however, they did not exhibit an increased risk of mortality in our COVID-19 cohort. Further studies with consideration of both emphysema extent and airflow limitation degree are warranted.

A Scalable Implementation of Anonymous Voting over Ethereum Blockchain.

We considered scalable anonymous voting on the Ethereum blockchain. We identified three major bottlenecks in implementation: (1) division overflow in encryption of voting values for anonymity; (2) large time complexity in tallying, which limited scalability in the number of candidates and voters; and (3) tallying failure due to "no votes" from registered voters. Previous schemes failed at tallying if one (or more) registered voters did not send encrypted voting values. Algorithmic solutions and implementation details are provided. An experiment using Truffle and Remix running on a desktop PC was performed for evaluation. Our scheme shows great reduction in gas, which measures the computational burden of smart contracts to be executed on Ethereum. For instance, our scheme consumed 1/53 of the gas compared to a state-of-the-art solution for 60 voters. Time complexity analysis shows that our scheme is asymptotically superior to known solutions. In addition, we propose a solution to the tallying failure due to the "no vote" from registered voters.

Anomalous hyperplastic anterior choroidal artery and its mimicker: a case series.

The anomalous hyperplastic anterior choroidal artery (AchoA) is a rare anomaly due to incomplete distal annexation between the primitive AchoA and posterior cerebral artery (PCA). It is often misdiagnosed or misunderstood as a duplicated or fetal type PCA because of its supply distribution. In addition, its aneurysm incidence is much higher than the overall aneurysm incidence of AchoA. Thus, endovascular procedures or surgery without comprehensive understanding of this anomaly can cause critical complications. Herein, we present a case series of anomalous hyperplastic AchoA and its mimicker, along with schematic images for comprehensive understanding.

Nasu-Hakola Disease.

Teaching Point: Nasu-Hakola disease (NHD) is characterized by multiple bone cysts in the appendicular skeleton and progressive presenile dementia.

Prognostic Implication of Volumetric Quantitative CT Analysis in Patients with COVID-19: A Multicenter Study in Daegu, Korea.

OBJECTIVE: Lung segmentation using volumetric quantitative computed tomography (CT) analysis may help predict outcomes of patients with coronavirus disease (COVID-19). The aim of this study was to investigate the relationship between CT volumetric quantitative analysis and prognosis in patients with COVID-19. MATERIALS AND METHODS: CT images from patients diagnosed with COVID-19 from February 18 to April 15, 2020 were retrospectively analyzed. CT with a negative finding, failure of quantitative analysis, or poor image quality was excluded. CT volumetric quantitative analysis was performed by automated volumetric methods. Patients were stratified into two risk groups according to CURB-65: mild (score of 0-1) and severe (2-5) pneumonia. Outcomes were evaluated according to the critical event-free survival (CEFS). The critical events were defined as mechanical ventilator care, ICU admission, or death. Multivariable Cox proportional hazards analyses were used to evaluate the relationship between the variables and prognosis. RESULTS: Eighty-two patients (mean age, 63.1 ± 14.5 years; 42 females) were included. In the total cohort, male sex (hazard ratio [HR], 9.264; 95% confidence interval [CI], 2.021-42.457; p = 0.004), C-reactive protein (CRP) (HR, 1.080 per mg/dL; 95% CI, 1.010-1.156; p = 0.025), and COVID-affected lung proportion (CALP) (HR, 1.067 per percentage; 95% CI, 1.033-1.101; p < 0.001) were significantly associated with CEFS. CRP (HR, 1.164 per mg/dL; 95% CI, 1.006-1.347; p = 0.041) was independently associated with CEFS in the mild pneumonia group (n = 54). Normally aerated lung proportion (NALP) (HR, 0.872 per percentage; 95% CI, 0.794-0.957; p = 0.004) and NALP volume (NALPV) (HR, 1.002 per mL; 95% CI, 1.000-1.004; p = 0.019) were associated with a lower risk of critical events in the severe pneumonia group (n = 28). CONCLUSION: CRP in the mild pneumonia group; NALP and NALPV in the severe pneumonia group; and sex, CRP, and CALP in the total cohort were independently associated with CEFS in patients with COVID-19.

Gadolinium-Based Neuroprognostic Magnetic Resonance Imaging Agents Suppress COX-2 for Prevention of Reperfusion Injury after Stroke.

Advancements in recanalization therapies have rendered reperfusion injury an important challenge for stroke management. It is essential to work toward effective therapeutics that protect the ischemic brain from reperfusion injury. Here, we report a new concept of neuroprognostic agents, which combine molecular diagnostic imaging and targeted neuroprotection for treatment of reperfusion injury after stroke. These neuroprognostic agents are inflammation-targeted gadolinium compounds conjugated with nonsteroidal anti-inflammatory drugs (NSAIDs). Our results demonstrated that gadolinium-based MRI contrast agents conjugated with NSAIDs suppressed the increase in cyclooxygenase-2 (COX-2) levels, ameliorated glial activation, and neuron damage that are phenotypic for stroke by mitigating neuroinflammation, which prevented reperfusion injury. In addition, this study showed that the neuroprognostic agents are promising T1 molecular MRI contrast agents for detecting precise reperfusion injury locations at the molecular level. Our results build on this new concept of neuroprognostics as a novel management strategy for ischemia-reperfusion injury, combining neuroprotection and molecular diagnostics.

Unexpected Intradural Lumbar Disk Herniation Found During Transforaminal Endoscopic Surgery.

BACKGROUND: Intradural disk herniation (IDH) is defined as the displacement of the intervertebral disk nucleus pulposus into the dural sac. In this lumbar lesion, the affected level differs from that of a traditional extradural herniation: 55% of cases occur at the level of L4-5, 16% at L3-4, and 10% at L5-S1. Upper lumbar IDH is extremely rare. We present a case of an IDH at the level of L2-3 that was diagnosed during endoscopic surgery. CASE DESCRIPTION: A 65-year-old male patient presented with severe radiating pain in the anterior right thigh that was accompanied by a tingling sensation in the right calf and difficulty in walking. Physical examination showed normal strength. Bladder and bowel function was normal, but mild hypesthesia of the L3 sensory dermatome was observed. Magnetic resonance imaging revealed a herniated disk at the level of L2-L3 that was compressing the right side of the dura. A percutaneous transforaminal endoscopic lumbar diskectomy was planned. After foraminoplasty, no ruptured disk fragments could be found. During dissection of the adhesion between the dura and protruded disk, the dura was torn. Interestingly, through this dural opening, multiple fragmented disk portions were visualized among the nerve rootlets. We removed some of the soft disk material; however, complete removal of the disk fragments was predicted to damage the rootlets, and we decided to convert to microscopic surgery. The disk fragments were successfully removed via durotomy under microscopic assistance. The incised dorsal dura was primarily sutured with continuous stitches, and the defect on the ventrolateral side of the dura was patched and sealed using a harvested inner ligamentum flavum and Gelfoam (Pfizer, New York, New York, USA). After the operation, the patient's symptoms improved. There was no cerebrospinal fluid leakage. CONCLUSIONS: If there is any preoperative clinical or radiologic suspicion of IDH, a microscopic surgical approach should be considered to be the first-line option, as this is a safe and effective method for achieving IDH removal and dura repair without a postoperative neurologic deficit. Even during endoscopic surgery, if the surgeon expects even minor complications, we suggest converting to open surgery. In addition, the adequate sealing of the dura may be sufficient to prevent cerebrospinal fluid leakage, without the need for dural suture and lumbar drainage.

Effects of a Mixed Reality-based Cognitive Training System Compared to a Conventional Computer-assisted Cognitive Training System on Mild Cognitive Impairment: A Pilot Study.

BACKGROUND: Mixed reality (MR) technology, which combines the best features of augmented reality and virtual reality, has recently emerged as a promising tool in cognitive rehabilitation therapy. OBJECTIVE: To investigate the effectiveness of an MR-based cognitive training system for individuals with mild cognitive impairment (MCI). METHODS: Twenty-one individuals aged 65 years and older who had been diagnosed with MCI were recruited for this study and were divided into two groups. Participants in the MR group (n=10, aged 70.5±4.2 years) received 30 minutes of training 3 times a week for 6 weeks using a newly developed MR-based cognitive training system. Participants in the control group (n=11, aged 72.6±5.3 years) received the same amount of training using a conventional computer-assisted cognitive training system. Both groups took the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD-K) both before and after intervention. To determine the effect of the intervention on cognitive function, we compared the difference in each group's CERAD-K scores. RESULTS: There was a statistically significant interaction between intervention (MR group vs control group) and time (before vs after intervention) as assessed by the Constructional Recall Test. The individuals with MCI who participated in the MR training showed significantly improved performance in visuospatial working memory compared with the individuals with MCI who participated in the conventional training. CONCLUSION: An MR-based cognitive training system can be used as a cognitive training tool to improve visuospatial working memory in individuals with MCI.

Comprehensive understanding of vascular anatomy for endovascular treatment of intractable oronasal bleeding.

Oronasal bleeding that continues despite oronasal packs or recurs after removal of the oronasal packs is referred to as intractable oronasal bleeding, which is refractory to conventional treatments. Severe craniofacial injury or tumor in the nasal or paranasal cavity may cause intractable oronasal bleeding. These intractable cases are subsequently treated with surgical ligation or endovascular embolization of the bleeding arteries. While endovascular embolization has several merits compared to surgical ligation, the procedure needs attention because severe complications such as visual disturbance or cerebral infarction can occur. Therefore, comprehensive understanding of the head and neck vascular anatomy is essential for a more effective and safer endovascular treatment of intractable oronasal bleeding.

Effect of three-dimensional spine stabilization exercise on trunk muscle strength and gait ability in chronic stroke patients: A randomized controlled trial.

BACKGROUND: Three-dimensional spine stabilization exercise can strengthen the trunk muscles with minimal spine movement. OBJECTIVE: To investigate the effects of the newly developed Spine Balance three-dimensional (3D) system on trunk strength and gait abilities of chronic stroke patients. METHODS: Twenty-four chronic stroke patients were randomly assigned to an experimental (n = 12) or control group (n = 12). The experimental and control groups performed spine stabilization exercise by using the newly developed Spine Balance 3D system and the well-known Bridge exercise thrice a week for 30 min per day for 7 weeks. Timed up and go (TUG) test, 10-m walking test (10-m WT), trunk muscle strength, and gait ability were evaluated before and after 7 weeks of intervention. RESULTS: The 10-m WT, TUG, walking speed, non-affected side step length, and distance in the experimental group, wherein trunk muscle strength was checked by using the Spine Balance 3D system evaluation program, showed more significant improvement than those in the control group (p < 0.05). CONCLUSION: We suggest that the newly developed Spine Balance 3D system can be a more useful therapeutic tool for rehabilitation of trunk muscle strength and gait abilities than bridge exercise-based spine stabilization exercise in chronic stroke patients.

Effects of visual fatigue caused by smartphones on balance function in healthy adults.

[Purpose] The purpose of this study was to determine the effects of visual fatigue caused by smartphone use on balance function. [Subjects and Methods] The participants consisted of 22 healthy male and female adults. Their postural stability, limit of stability, and limit of stability running time were evaluated using a computerized posturography apparatus before and after inducing visual fatigue. Postural stability and the limit of stability were divided into static and dynamic conditions. [Results] There were significant differences between the dynamic postural stability, the static and dynamic limit of stability, and both the static and dynamic limit of stability running times after the induction of visual fatigue. [Conclusion] The results showed that visual fatigue caused by smartphone use has a negative effect on balance function. Therefore, reducing visual fatigue through proper rest is necessary.

Relationship between dynamic balance and spatiotemporal gait symmetry in hemiplegic patients with chronic stroke.

BACKGROUND: Poor dynamic balance, which is common after stroke, may affect gait function. In particular, spatiotemporal asymmetrical gait patterns may occur in hemiplegic patients after stroke. OBJECTIVE: This study aimed to assess the relationship between dynamic balance and spatiotemporal gait symmetry in patients with chronic hemiplegic stroke. METHODS: To calculate symmetry ratios for step length (spatial parameter) and swing time (temporal parameter), 41 patients with chronic stroke walked at a comfortable speed. The dynamic balance measures included limit of stability (LOS) during standing and heel-to-heel base of support (H-H BOS) during gait. Analysis of correlations between various measures was performed. RESULTS: The overall LOS score correlated with temporal gait symmetry (r = 0.66). The forward, backward, paretic, and non-paretic direction LOS scores were related to temporal gait symmetry (r = 0.38-0.62). The H-H BOS was correlated with temporal (r = -0.63) and spatial (r = -0.36) gait symmetries. Other dynamic balance variables were not significantly correlated with spatial gait symmetry. CONCLUSION: Thus, control of dynamic balance abilities is related to the magnitude of temporal gait symmetry. This observation suggests that rehabilitation strategies that improve dynamic balance may enhance temporal gait symmetry in post-stroke patients.

Effects of 3-Dimensional Lumbar Stabilization Training for Balance in Chronic Hemiplegic Stroke Patients: A Randomized Controlled Trial.

OBJECTIVE: To investigate the effects of the newly developed Spine Balance 3D system on the balance and gait abilities of hemiplegic stroke patients. METHODS: Twenty-eight hemiplegic patients with chronic stroke were randomly assigned to an experimental (n=14) or control group (n=14). The experimental and control groups performed balance training by using the newly developed Spine Balance 3D system and the well-known Biodex Balance System 30 minutes per day, three times a week for 7 weeks. The Berg Balance Scale (BBS), 10-m walking test (10mWT), Timed Up and Go Test (TUG), Functional Reach Test (FRT), the Korean version of the Fall Efficacy Scale-International (KFES-I), trunk muscle strength and stability were evaluated before and after 7 weeks of intervention. RESULTS: The 10mWT improved significantly (p=0.001) in the experimental group (using the Spine Balance 3D system) but not in the control group, and core muscle strength, which we checked using Spine Balance 3D system evaluation program, improved more in the experimental group as well. The results of the BBS, FRT, TUG, KFES-I, and Biodex Balance System evaluation program improved in both groups after 7 weeks of balance training. CONCLUSION: We suggest that the newly-developed Spine Balance 3D system can be a more useful therapeutic tool for gait and dynamic balance rehabilitation in hemiplegic patients than a conventional 2D-based balance training system. A large-scale randomized controlled study is needed to prove the effect of this system.

Effects of treadmill training with the eyes closed on gait and balance ability of chronic stroke patients.

[Purpose] The purpose of this study was to compare the effect of treadmill walking with the eyes closed and open on the gait and balance abilities of chronic stroke patients. [Subjects and Methods] Thirty patients with chronic stroke participated in this study. The treadmill gait training for each group lasted 40 minutes, and sessions were held 3 times a week for 4 weeks. Gait ability was measured using a Biodex Gait Trainer Treadmill System. Balance ability was measured using a Biodex Balance System. [Results] After the treadmill training' the treadmill training with eyes closed (TEC) group showed significant improvements in walking distance' step length' coefficient of variation' and limit of stability (overall' lateral affected' forward lateral unaffected) compared to the treadmill training with eyes open (TEO) group. [Conclusion] The walking and balance abilities of the TEC participants showed more improvement after the treadmill walking sessions than those of the TEO participants. Therefore' treadmill walking with visual deprivation may be useful for the rehabilitation of patients with chronic stroke.