Bright diffusion sign: A sensitive and specific radiologic biomarker for multinodular and vacuolating neuronal tumor.

BACKGROUND AND PURPOSE: Accurate differentiation between multinodular and vacuolating neuronal tumor (MVNT) and dysembryoplastic neuroepithelial tumor (DNET) is important for treatment decision-making. We aimed to develop an accurate radiologic diagnostic model for differentiating MVNT from DNET using T2WI and diffusion-weighted imaging (DWI). MATERIALS AND METHODS: A total of 56 patients (mean age, 47.48±17.78 years; 31 women) diagnosed with MVNT (n = 37) or DNET (n = 19) who underwent brain MRI, including T2WI and DWI, were included. Two board-certified neuroradiologists performed qualitative (bubble appearance, cortical involvement, bright diffusion sign, and bright apparent diffusion coefficient [ADC] sign) and quantitative (nDWI and nADC) assessments. A diagnostic tree model was developed with significant and reliable imaging findings using an exhaustive chi-squared Automatic Interaction Detector (CHAID) algorithm. RESULTS: In visual assessment, the imaging features that showed high diagnostic accuracy and interobserver reliability were the bright diffusion sign and absence of cortical involvement (bright diffusion sign: accuracy, 94.64 %; sensitivity, 91.89 %; specificity, 100.00 %; interobserver agreement, 1.00; absence of cortical involvement: accuracy, 92.86 %; sensitivity, 89.19 %; specificity, 100.00 %; interobserver agreement, 1.00). In quantitative analysis, nDWI was significantly higher in MVNT than in DENT (1.52 ± 0.34 vs. 0.91 ± 0.27, p < 0.001), but the interobserver agreement was fair (intraclass correlation coefficient = 0.321). The overall diagnostic accuracy of the tree model with visual assessment parameters was 98.21 % (55/56). CONCLUSION: The bright diffusion sign and absence of cortical involvement are accurate and reliable imaging findings for differentiating MVNT from DNET. By using simple, intuitive, and reliable imaging findings, such as the bright diffusion sign, MVNT can be accurately differentiated from DNET.

Developing Hemodynamic Valve Deterioration and Mortality in Aortic Valve Replacement.

BACKGROUND: As life span increases, in patients having a bioprosthetic valve, the development of hemodynamic valve deterioration (HVD) is an important concern. We evaluated the association of developing HVD to survival in patients undergoing surgical aortic valve replacement (SAVR). METHODS: The individuals undergoing isolated SAVR and serial echocardiography exams (interval >30 d) were included in this study. HVD was defined as mean pressure gradient ≥ 20 mmHg, mean pressure gradient ≥10 mmHg higher than in the baseline exam, or more than moderate regurgitation on Doppler echocardiography (moderate and severe grade). A time-dependent Cox proportional hazard model was used for this study. RESULTS: A total of 631 patients were included. The mean age was 71.8 ± 6.1 y old (female: 53.6%). HVD was found in 259 patients (41%) during echocardiographic follow-up (mean 3.3 ± 3.0 y). Patient-prosthetic mismatch was found in 174 patients. One hundred and twenty-six patients died during follow-up (median 62.1 mo, interquartile range 31.1-96.8). The development of HVD was an independent risk factor for death during follow-up (P = 0.038, hazard ratio 1.46, 95% confidential interval: 1.02-2.08). CONCLUSIONS: HVD was common after bioprosthetic SAVR during mid-term follow-up. Developing HVD, including moderate and severe grades, was associated with a poor survival rate compared with patients without HVD.

Clinical prediction rule for identifying older patients with toxigenic clostridioides difficile at the time of hospital admission.

BACKGROUND: This study aimed to develop and validate a clinical prediction rule to screen older patients at risk of being toxigenic Clostridioides difficile carriers at the time of hospital admission. METHODS: This retrospective case-control study was performed at a university-affiliated hospital. Active surveillance using a real-time polymerase chain reaction (PCR) assay for the toxin genes of C. difficile was conducted among older patients (≥ 65 years) upon admission to the Division of Infectious Diseases of our institution. This rule was drawn from a derivative cohort between October 2019 and April 2021 using a multivariable logistic regression model. Clinical predictability was evaluated in the validation cohort between May 2021 and October 2021. RESULTS: Of 628 PCR screenings for toxigenic C. difficile carriage, 101 (16.1%) yielded positive findings. To establish clinical prediction rules in the derivation cohort, the formula was derived using significant predictors for toxigenic C. difficile carriage at admission, such as septic shock, connective tissue diseases, anemia, recent use of antibiotics, and recent use of proton-pump inhibitors. In the validation cohort, the sensitivity, specificity, and positive and negative predictive values of the prediction rule, based on a cut-off value of ≥ 0.45, were 78.3%, 70.8%, 29.5%, and 95.4%, respectively. CONCLUSION: This clinical prediction rule for identifying toxigenic C. difficile carriage at admission may facilitate the selective screening of high-risk groups. To implement it in a clinical setting, more patients from other medical institutions need to be prospectively examined.

Intravenous Tranexamic Acid Improves Visual Clarity During Synovectomy in Patients Undergoing Arthroscopic Rotator Cuff Repair: A Double-Blind, Randomized Controlled Study.

PURPOSE: To assess the effects of intravenous tranexamic acid (TXA) on visual clarity at various surgical stages and the correlation between the severity of synovitis and bursitis and the grade of visual clarity in patients undergoing arthroscopic shoulder surgery under an interscalene brachial plexus block. METHODS: This double-blind, randomized controlled study included patients undergoing arthroscopic rotator cuff repair. The TXA group underwent injection of a 100-mL mixture of 1,000 mg of TXA and normal saline solution intravenously whereas the control group was administered the same volume of normal saline solution at 10 minutes preoperatively. Visual clarity was rated according to a 3-grade visual clarity scoring system from grade 1 (clear) to grade 3 (poor) at 4 surgical stages (I, intra-articular soft-tissue procedures including synovectomy; II, acromioplasty; III, bursectomy; and IV, greater tuberoplasty). The primary outcome was arthroscopic visual clarity. The secondary outcomes were medications administered for hemodynamic stability, length of hospital stay, and thromboembolic events. RESULTS: Altogether, 63 patients were included in the study; they were divided into the TXA group, comprising 32 patients, and the control group, comprising 31 patients. The TXA group showed significantly better visual clarity than the control group (median [interquartile range], 1 [1-2] vs 2 [1-2]; P = .027) during stage I but not during stages II through IV. Spearman correlation analysis revealed a significant correlation between synovitis and visual clarity grade during synovectomy (correlation coefficient, 0.393; P = .001) but not between bursitis and visual clarity grade during bursectomy. Deep vein thrombosis and pulmonary embolism did not occur in either group. CONCLUSIONS: Intravenous TXA can improve visual clarity during intra-articular soft-tissue procedures, including synovectomy. However, it does not have a significant effect during acromioplasty, bursectomy, and greater tuberoplasty. TXA can be used to improve visual clarity in patients with suspected severe synovitis. LEVEL OF EVIDENCE: Level I, randomized controlled trial.

Exploring ideal operative time for best outcomes in gastric cancer surgery: A multi-institutional study based on KLASS-07 database.

Objective: While a rushed operation can omit essential procedures, prolonged operative time results in higher morbidity. Nevertheless, the optimal operative time range remains uncertain. This study aimed to estimate the ideal operative time range and evaluate its applicability in laparoscopic cancer surgery. Methods: A prospectively collected multicenter database of 397 patients who underwent laparoscopic distal gastrectomy were retrospectively reviewed. The ideal operative time range was statistically calculated by separately analyzing the operative time of uneventful surgeries. Finally, intraoperative and postoperative outcomes were compared among the shorter, ideal, and longer operative time groups. Results: The statistically calculated ideal operative time was 135.4-165.4 min. The longer operative time (LOT) group had a lower rate of uneventful, perfect surgery than the ideal or shorter operative time (IOT/SOT) group (2.8% vs. 8.8% and 2.2% vs. 13.4%, all P<0.05). Longer operative time increased bleeding, postoperative morbidities, and delayed diet and discharge (all P<0.05). Particularly, an uneventful, perfect surgery could not be achieved when the operative time exceeded 240 min. Regardless of ideal time range, SOT group achieved the highest percentage of uneventful surgery (13.4%), which was possible by surgeon's ability to retrieve a higher number of lymph nodes and perform ≥150 gastrectomies annually. Conclusions: Operative time longer than the ideal time range (especially ≥240 min) should be avoided. If the essential operative procedure were faithfully conducted without compromising oncological safety, an operative time shorter than the ideal range leaded to a better prognosis. Efforts to minimize operative time should be attempted with sufficient surgical experience.

Synthetic Time of Flight Magnetic Resonance Angiography Generation Model Based on Cycle-Consistent Generative Adversarial Network Using PETRA-MRA in the Patients With Treated Intracranial Aneurysm.

BACKGROUND: Pointwise encoding time reduction with radial acquisition (PETRA) magnetic resonance angiography (MRA) is useful for evaluating intracranial aneurysm recurrence, but the problem of severe background noise and low peripheral signal-to-noise ratio (SNR) remain. Deep learning could reduce noise using high- and low-quality images. PURPOSE: To develop a cycle-consistent generative adversarial network (cycleGAN)-based deep learning model to generate synthetic TOF (synTOF) using PETRA. STUDY TYPE: Retrospective. POPULATION: A total of 377 patients (mean age: 60 ± 11; 293 females) with treated intracranial aneurysms who underwent both PETRA and TOF from October 2017 to January 2021. Data were randomly divided into training (49.9%, 188/377) and validation (50.1%, 189/377) groups. FIELD STRENGTH/SEQUENCE: Ultra-short echo time and TOF-MRA on a 3-T MR system. ASSESSMENT: For the cycleGAN model, the peak SNR (PSNR) and structural similarity (SSIM) were evaluated. Image quality was compared qualitatively (5-point Likert scale) and quantitatively (SNR). A multireader diagnostic optimality evaluation was performed with 17 radiologists (experience of 1-18 years). STATISTICAL TESTS: Generalized estimating equation analysis, Friedman's test, McNemar test, and Spearman's rank correlation. P < 0.05 indicated statistical significance. RESULTS: The PSNR and SSIM between synTOF and TOF were 17.51 [16.76; 18.31] dB and 0.71 ± 0.02. The median values of overall image quality, noise, sharpness, and vascular conspicuity were significantly higher for synTOF than for PETRA (4.00 [4.00; 5.00] vs. 4.00 [3.00; 4.00]; 5.00 [4.00; 5.00] vs. 3.00 [2.00; 4.00]; 4.00 [4.00; 4.00] vs. 4.00 [3.00; 4.00]; 3.00 [3.00; 4.00] vs. 3.00 [2.00; 3.00]). The SNRs of the middle cerebral arteries were the highest for synTOF (synTOF vs. TOF vs. PETRA; 63.67 [43.25; 105.00] vs. 52.42 [32.88; 74.67] vs. 21.05 [12.34; 37.88]). In the multireader evaluation, there was no significant difference in diagnostic optimality or preference between synTOF and TOF (19.00 [18.00; 19.00] vs. 20.00 [18.00; 20.00], P = 0.510; 8.00 [6.00; 11.00] vs. 11.00 [9.00, 14.00], P = 1.000). DATA CONCLUSION: The cycleGAN-based deep learning model provided synTOF free from background artifact. The synTOF could be a versatile alternative to TOF in patients who have undergone PETRA for evaluating treated aneurysms. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 1.

Development and validation of visual grading system for stenosis in intracranial atherosclerotic disease on time-of-flight magnetic resonance angiography.

OBJECTIVES: Although the overestimation problem of time-of-flight magnetic resonance angiography (TOF-MRA) applying the warfarin-aspirin symptomatic intracranial disease (WASID) method to assess intracranial arterial stenosis has often been suggested, no pertinent grading system for TOF-MRA has been developed. We aimed to develop and evaluate the performance of a visual grading system for intracranial arterial stenosis on TOF-MRA (MRAVICAST). METHODS: This single-center cohort study analyzed prospective observational registry data from a comprehensive stroke center between January 2014 and February 2020. Patients with confirmed stenosis of the intracranial large arteries who underwent confirmative digital subtraction angiography (DSA) were included; a 4-point grading system was developed based on physical characteristics of TOF-MRA. The overall diagnostic accuracies of MRAVICAST for each grade, interobserver reproducibility, and positive predictive values for > 50% and > 70% stenoses were evaluated. RESULTS: We analyzed 132 segments with intracranial atherosclerotic stenosis from 71 patients (34 men and 37 women; mean age, 61.0 ± 15.25 years; range, 21-89 years). The overall diagnostic accuracy of MRAVICAST (93.9%, 124/132) was higher than that of MRAWASID (50.8%, 67/132) for each grade. The degree of stenosis did not differ significantly between MRAVICAST and DSAWASID (p = .849). Regarding reproducibility, MRAVICAST demonstrated excellent interobserver agreement (ICC, 0.989; 95% CI, 0.979-0.999). The positive predictive values of MRAVICAST for the diagnosis of > 50% and > 70% stenoses were 97.3% and 100.0%, respectively. CONCLUSIONS: The new intuitive grading system accurately and reliably determined the degree of stenosis in intracranial arterial atherosclerosis patients. MRAVICAST could be a versatile alternative to MRAWASID for evaluating intracranial arterial stenosis. KEY POINTS: • In this retrospective diagnostic study (sample: 132 stenotic segments), the overall accuracy of the visual grading system (MRAVICAST) was 94%, and positive predictive value for > 50% stenosis was 97%. • In the era of medical treatment for intracranial atherosclerotic stenosis, MRAVICAST could be a versatile alternative method to MRAWASID for evaluating intracranial arterial stenosis.

Lower Incidence of Postoperative Urinary Retention in Robotic Total Mesorectal Excision for Low Rectal Cancer Compared with Laparoscopic Surgery.

INTRODUCTION: The incidence and clinical significance of postoperative urinary retention (POUR) remain high. This study aimed to evaluate the incidence of POUR and related risk factors in patients who underwent total mesorectal excision (TMR) for low rectal cancer. METHODS: This study is a retrospective review of a prospectively collected colorectal database from a single center. Data from patients who underwent surgery for low rectal cancer between September 2006 and May 2017 were analyzed to assess the risk factors of POUR. POUR was considered inability to void after urinary catheter removal requiring catheter reinsertion and difficulty in bladder emptying requiring intermittent catheterization. RESULTS: Of 555 patients with low rectal cancer, 78 (14.1%) developed POUR. Based on multivariate logistic regression analysis, laparoscopic TMR (odds ratio [OR]; 2.114, 95% confidence interval [CI]; 1.212-3.689, p = 0.008) and postoperative ileus (OR; 2.389, 95% CI; 1.282-4.450, p = 0.006) were independent risk factors of POUR. Male gender, advanced age, neoadjuvant chemoradiation, longer operative time, abdominoperineal resection, and lateral pelvic lymph node dissection were not associated with POUR. Advanced age over 65 years also failed to show statistical significance (OR; 1.604, 95% CI; 0.965-2.668, p = 0.068). CONCLUSION: Laparoscopic approach and postoperative ileus are risk factors for POUR after low rectal cancer surgery. We postulate that the benefits of robotic surgical systems compared to a laparoscopic approach may reduce the incidence of POUR.

Maternal and Neonatal Outcomes in Pregnant Women With Coronavirus Disease 2019 in Korea.

BACKGROUND: This study aimed to describe the maternal, obstetrical, and neonatal outcomes in pregnant women with coronavirus disease 2019 (COVID-19) and identify the predictors associated with the severity of COVID-19. METHODS: This multicenter observational study included consecutive pregnant women admitted because of COVID-19 confirmed using reverse transcriptase-polymerase chain reaction (RT-PCR) test at 15 hospitals in the Republic of Korea between January 2020 and December 2021. RESULTS: A total of 257 women with COVID-19 and 62 newborns were included in this study. Most of the patients developed this disease during the third trimester. Nine patients (7.4%) developed pregnancy-related complications. All pregnant women received inpatient treatment, of whom 9 (3.5%) required intensive care, but none of them died. The gestational age at COVID-19 diagnosis (odds ratio [OR], 1.096, 95% confidence interval [CI], 1.04-1.15) and parity (OR, 1.703, 95% CI, 1.13-2.57) were identified as significant risk factors of severe diseases. Among women who delivered, 78.5% underwent cesarean section. Preterm birth (38.5%), premature rupture of membranes (7.7%), and miscarriage (4.6%) occurred, but there was no stillbirth or neonatal death. The RT-PCR test of newborns' amniotic fluid and umbilical cord blood samples was negative for severe acute respiratory syndrome coronavirus 2. CONCLUSION: At the time of COVID-19 diagnosis, gestational age and parity of pregnant women were the risk factors of disease severity. Vertical transmission of COVID-19 was not observed, and maternal severity did not significantly affect the neonatal prognosis.

Surgical Outcomes of Hepatocellular Carcinoma With Bile Duct Tumor Thrombus: A Korea-Japan Multicenter Study.

OBJECTIVE: To identify optimal surgical methods and the risk factors for long-term survival in patients with hepatocellular carcinoma accompanied by macroscopic bile duct tumor thrombus (BDTT). SUMMARY BACKGROUND DATA: Prognoses of patients with hepatocellular carcinoma accompanied by BDTT have been known to be poor. There have been significant controversies regarding optimal surgical approaches and risk factors because of the low incidence and small number of cases in previous reports. METHODS: Records of 257 patients from 32 centers in Korea and Japan (1992-2014) were analyzed for overall survival and recurrence rate using the Cox proportional hazard model. RESULTS: Curative surgery was performed in 244 (94.9%) patients with an operative mortality of 5.1%. Overall survival and recurrence rate at 5 years was 43.6% and 74.2%, respectively. TNM Stage (P < 0.001) and the presence of fibrosis/cirrhosis (P = 0.002) were independent predictors of long-term survival in the Cox proportional hazards regression model. Both performing liver resection equal to or greater than hemihepatectomy and combined bile duct resection significantly increased overall survival [hazard ratio, HR = 0.61 (0.38-0.99); P = 0.044 and HR = 0.51 (0.31-0.84); P = 0.008, respectively] and decreased recurrence rate [HR = 0.59 (0.38-0.91); P = 0.018 and HR = 0.61 (0.42-0.89); P = 0.009, respectively]. CONCLUSIONS: Clinical outcomes were mostly influenced by tumor stage and underlying liver function, and the impact of BDTT to survival seemed less prominent than vascular invasion. Therefore, an aggressive surgical approach, including major liver resection combined with bile duct resection, to increase the chance of R0 resection is strongly recommended.

Cervical necrotic lymphadenopathy: a diagnostic tree analysis model based on CT and clinical findings.

OBJECTIVES: To establish a diagnostic tree analysis (DTA) model based on computed tomography (CT) findings and clinical information for differential diagnosis of cervical necrotic lymphadenopathy, especially in regions where tuberculous lymphadenitis and Kikuchi disease are common. METHODS: A total of 290 patients (147 men and 143 women; mean age (years), 46.2 ± 19.5; range, 3-91) with pathologically confirmed metastasis (n = 110), tuberculous lymphadenitis (n = 73), Kikuchi disease (n = 71), and lymphoma (n = 36) who underwent contrast-enhanced neck CT were included. The patients were randomly divided into training (86%, 248/290) and validation (14%, 42/290) datasets to assess diagnostic performance of the DTA model. Two sorts of DTA models were created using a classification and regression tree algorithm on the basis of CT findings alone and that combined with clinical findings. RESULTS: In the DTA model based on CT findings alone, perinodal infiltration, number of the necrotic foci, percentage of necrotic lymph node (LN), degree of necrosis, margin and shape of the necrotic portion, shape of the LN, and enhancement ratio (cutoff value, 1.93) were significant predictors for differential diagnosis of cervical necrotic lymphadenopathy. The overall accuracy was 80.6% and 73.8% in training and validation datasets. In the model based on imaging and clinical findings, tenderness, history of underlying malignancy, percentage of necrotic LN, degree of necrosis, and number of necrotic foci were significant predictors. The overall accuracy was 87.1% and 88.1% in training and external validation datasets. CONCLUSIONS: The DTA model based on CT imaging and clinical findings may be helpful for the diagnosis of cervical necrotic lymphadenopathy. KEY POINTS: • The diagnostic tree analysis model based on CT may be useful for differential diagnosis of cervical necrotic lymphadenopathy. • Perinodal infiltration, number of necrotic foci, percentage of necrotic lymph nodes, degree of necrosis, margin and shape of necrotic portion, lymph node shape, and enhancement ratio were the most significant predictors.

Predicting the Development of Surgically Induced Chronic Kidney Disease After Total Nephrectomy Using Body Surface Area-Adjusted Renal Cortical Volume on CT Angiography.

OBJECTIVE: The purpose of this study was to predict the probability of surgically induced chronic kidney disease (CKD) developing in patients who underwent total nephrectomy by measuring the body surface area (BSA)-adjusted renal cortical volume (RCV) with preoperative CT angiography (CTA). MATERIALS AND METHODS: A total of 105 patients with a normal preoperative estimated glomerular filtration rate (eGFR) who underwent preoperative CTA and subsequent total nephrectomy for kidney donation (n = 67) or a renal tumor (n = 38) were included in this retrospective study. Patients were divided into group A (patients without surgically induced CKD; n = 61) and group B (patients with surgically induced CKD; n = 44) according to postoperative renal function. The preoperative and postoperative eGFR and other laboratory findings were collected, and the BSA-adjusted postnephrectomy RCV was measured using a semiautomated segmentation technique on CTA. Multiple logistic regression analysis was used to determine the formula for predicting the probability of development of surgically induced CKD; external validation was conducted using the validation dataset (n = 28). RESULTS: The estimated probability of surgically induced CKD developing can be calculated using the following formula: logit (probability of surgically induced CKD developing) = [1.431 × I (reason for operation was renal tumor)] + (-0.097 × preoperative eGFR) + (-0.033 × BSA-adjusted postnephrectomy RCV) + 10.937, where I denotes an indicator function (I = 1, reason for operation was renal tumor; I = 0, reason for operation was kidney donation). The optimal cutoff value derived from 10,000 bootstrapped samples was 0.444 (95% CI, 0.298-0.681). The formula was determined to be a good tool for prediction of surgically induced CKD on external validation (AUC value, 0.894). CONCLUSION: The probability of CKD developing in patients who undergo total nephrectomy may be predicted using a BSA-adjusted postnephrectomy RCV volume measured on preoperative CTA.

Determining the clinical significance of co-colonization of vancomycin-resistant enterococci and methicillin-resistant Staphylococcus aureus in the intestinal tracts of patients in intensive care units: a case-control study.

BACKGROUND: The emergence of vancomycin-resistant Staphylococcus aureus (VRSA) has become a global concern for public health. The proximity of vancomycin-resistant enterococcus (VRE) and methicillin-resistant S. aureus (MRSA) is considered to be one of the foremost risk factors for the development of VRSA. This study aimed to determine the incidence, risk factors, and clinical outcomes of intestinal co-colonization with VRE and MRSA. METHODS: A case-control study was conducted in 52-bed intensive care units (ICUs) of a university-affiliated hospital from September 2012 to October 2017. Active surveillance using rectal cultures for VRE were conducted at ICU admission and on a weekly basis. Weekly surveillance cultures for detection of rectal MRSA were also conducted in patients with VRE carriage. Patients with intestinal co-colonization of VRE and MRSA were compared with randomly selected control patients with VRE colonization alone (1:1). Vancomycin minimum inhibitory concentrations (MICs) for MRSA isolates were determined by the Etest. RESULTS: Of the 4679 consecutive patients, 195 cases and 924 controls were detected. The median monthly incidence and duration of intestinal co-colonization with VRE and MRSA were 2.3/1000 patient-days and 7 days, respectively. The frequency of both MRSA infections and mortality attributable to MRSA were higher in the case group than in the control group: 56.9% vs. 44.1% (P = 0.011) and 8.2% vs. 1.0% (P = 0.002), respectively. Independent risk factors for intestinal co-colonization were enteral tube feeding (odds ratio [OR], 2.09; 95% confidence interval [CI] 1.32-3.32), metabolic diseases (OR, 1.75; 95% CI 1.05-2.93), male gender (OR, 1.62; 95% CI 1.06-2.50), and Charlson comorbidity index < 3 (OR, 3.61; 95% CI 1.88-6.94). All MRSA isolates from case patients were susceptible to vancomycin (MIC ≤ 2 mg/L). CONCLUSIONS: Our study indicates that intestinal co-colonization of VRE and MRSA occurs commonly among patients in the ICU with MRSA endemicity, which might be associated with poor clinical outcomes.

Effects of Different Body Postures on the Intraocular Pressure in Patients with Primary Angle-Closure Disease.

SIGNIFICANCE: Eyes with primary angle-closure disease showed higher intraocular pressure (IOP) in the recumbent postures including supine and lateral decubitus (LD) positions compared with the sitting position. PURPOSE: The purpose of this study was to investigate the effects of different body postures on the IOP in eyes with primary angle-closure suspect (PACS), primary angle closure (PAC), or primary angle-closure glaucoma (PACG). METHODS: This is a comparative case series of 31 patients with bilateral PAC disease, such as PACS, PAC, and PACG. The IOP was measured using Tonopen AVIA in sitting, supine, and right or left LD positions. Patients were instructed to rest their heads on the pillows in supine and LD positions. The eye on the lower side in the LD position was called dependent eye. The main outcome was the difference in IOP among different body postures. RESULTS: Among the 62 eyes (31 patients), PACG, PAC, and PACS were noted in 44, 12, and 6 eyes, respectively. The IOP was not significantly different between the two eyes in sitting and supine positions, whereas the IOP was significantly higher in the dependent eye than in the nondependent eye in LD positions. Compared with that measured in the supine position, IOP differences of the dependent eye were higher than those of the nondependent eye when measured in LD position (right LD vs. supine, P = .02; left LD vs. supine, P = .01). In addition, when the study patients were divided into three groups according to their diagnosis, no significant differences were observed in the IOPs and IOP differences among the three groups. CONCLUSIONS: Posture-induced IOP changes were comparable among eyes with PACS, PAC, and PACG.

Effects of a high level of illumination before sleep at night on chorioretinal thickness and ocular biometry.

The choroid is affected by many factors. One of the factors, change in illumination has been suggested to influence choroidal thickness. However, the effects of bright light before sleep at night on the human eye are not well established. The purpose of this study was to investigate the effects of a high level of illumination in the evening on ocular measurements. Twenty-seven men with myopia spent seven consecutive nights in the sleep laboratory. During the first two nights, subjects were exposed to light at 150 lux between 20:00 and midnight. Then, for five consecutive nights, they were exposed to ambient light at 1000 lux between 20:00 and midnight. Ocular parameters and their diurnal variations were compared between the two periods and the effects of a high level of illumination were analyzed. After subjects were exposed to 1000 lux of illumination, axial length increased with borderline significance (p = 0.064). Macular volume and retinal thickness did not change. However, subfoveal choroidal thickness after exposure to 1000 lux of illumination (245.37 ± 52.84 µm) was significantly lower than that after 150 lux of illumination (268.00 ± 57.10 µm), (p < 0.001). Significant diurnal variations were found in mean keratometry (p = 0.039), intraocular pressure (IOP, p = 0.003), ocular perfusion pressure (OPP, p < 0.0001), macular volume (p = 0.019), and subfoveal choroidal thickness (p < 0.0001). A high level of illumination had significant effects on only IOP and OPP (p = 0.027 and 0.017, respectively). Bright light exposure before sleep at an intensity as high as 1000 lux reduced subfoveal choroidal thickness in healthy young men. In conclusion, diurnal variation in choroidal thickness can be affected by bright light exposure before sleep.

Hepatic Parenchymal Heterogeneity as a Marker for Oxaliplatin-Induced Sinusoidal Obstruction Syndrome: Correlation With Treatment Response of Colorectal Cancer Liver Metastases.

OBJECTIVE: The objective of our study was to evaluate the influence of oxaliplatin-based chemotherapy (OBC)-induced hepatic parenchymal heterogeneity detected on contrast-enhanced CT scans on response of liver metastasis. We chose to study hepatic parenchymal heterogeneity on the basis of the assumption that hepatic parenchymal heterogeneity may indicate the presence of chemotherapy-induced sinusoidal obstruction syndrome (SOS). MATERIALS AND METHODS: For this retrospective study, 104 patients with hepatic metastases from colorectal cancer (male-female ratio, 66:38; age range, 20-80 years) who had undergone OBC and serial CT studies were consecutively registered. Two blinded imagers independently scored CT images using a 5-point scale to determine the severity of newly developed hepatic parenchymal heterogeneity after OBC. Subsequently, two radiologists evaluated tumor response to OBC using a 4-point ordinal scale. We performed generalized estimating equation (GEE) analysis using cumulative logits to account for the effect of hepatic parenchymal heterogeneity severity on the cumulative tumor response probability. RESULTS: The interobserver agreements for the severity of hepatic parenchymal heterogeneity were excellent (κ = 0.825). GEE analyses showed that the severity of post-OBC hepatic parenchymal heterogeneity, number of chemotherapy sessions, and presence of other organ metastases were significant predictors of tumor response; these three factors also showed significance in the final GEE model (p < 0.0001 for severity of hepatic parenchymal heterogeneity for both readers; p = 0.011 and 0.010 for the number of chemotherapy sessions for readers 1 and 2; p = 0.046 and 0.012 for the presence of other organ metastases for readers 1 and 2). CONCLUSION: Hepatic parenchymal heterogeneity detected on contrast-enhanced CT of patients with hepatic metastases from colorectal cancer who have undergone OBC may indicate the presence of SOS, and the more severe the SOS, the worse the tumor response of hepatic metastasis to oxaliplatin is expected to be.

Magnetic Resonance Imaging-Based Prostate-Specific Antigen Density for Prediction of Gleason Score Upgrade in Patients With Low-Risk Prostate Cancer on Initial Biopsy.

OBJECTIVE: The aim of this study was to assess the utility of prostate-specific antigen density (PSAD) calculated using magnetic resonance imaging for predicting Gleason score (GS) upgrade in patients with low-risk prostate cancer on biopsy. METHODS: Seventy-three patients were divided into 2 groups according to the concordance between biopsy and prostatectomy GS: group 1 (6/6) and group 2 (6/≥7). Magnetic resonance imaging-based PSAD, prostate volume, prostate-specific antigen (PSA), and age were compared between the 2 groups. Logistic regression and receiver operating characteristic curve analysis were performed. RESULTS: Gleason score was upgraded in 40 patients. Patients in group 2 had significantly higher PSAD and PSA values and smaller prostate volume than did those in group 1. Prostate-specific antigen density of 0.26 ng/mL per cm or higher, PSA of 7.63 ng/mL or higher, and prostate volume of 25.1 cm or less were related to GS upgrade, with area-under-the-curve values of 0.765, 0.721, and 0.639, respectively. CONCLUSIONS: Magnetic resonance imaging-based PSAD could help in predicting postoperative GS upgrade in patients with low-risk prostate cancer.

A Method of Radial Nerve Length Measurement Based on Cadaveric Investigation.

OBJECTIVE: To determine the most reliable method to measure the length of the radial nerve during a nerve conduction study (NCS). DESIGN: Cadaveric investigation. SETTING: A practical anatomy research laboratory in a university. PARTICIPANTS: Fresh cadavers (N=10), with 1 cadaver for study design and 9 for data. INTERVENTIONS: Design of measurement methods using cadaver dissection and comparison of the measured values to the true length in 18 arms of 9 cadavers. MAIN OUTCOME MEASURES: Four points (A, B, C, D) were determined: (A) proximal stimulation point in NCS; (B) point at the elbow crease; (C) point in the midforearm; and (D) distal stimulation point 5cm above the extensor indicis. The true length of the radial nerve between the stimulus points (points A and D) in NCS was compared with the measured values by summation of the straight line segments between those points with various combinations. The difference in root mean square error (RMSE) of the distance measured by each method compared with the true length was calculated to determine the best measurement method. RESULTS: The closest distance to the true length (28.7±2.8cm) in the cadaveric investigation was obtained using the summation of straight line segments between points A, B, and D (A-B-D, RMSE=.72cm), followed by the A-B-C-D distance (RMSE=.87cm) and the A-D distance (RMSE=1.38cm) methods, in sequence. The former 2 distance measurements were relatively closer to the true length than the latter measurement method. CONCLUSIONS: Multiple segmentation measurement methods reflected the course of the radial nerve better than a single linear measurement method. We suggest that the distance measured using a stopover point near the lateral epicondyle between 2 stimulus points (A-B-D distance) is closer to the true length of the nerve.

Correlation of CT imaging features and tumor size with Fuhrman grade of clear cell renal cell carcinoma.

Background Identification of clinical features to determine the aggressive potential of tumors is highly warranted to stratify patients for adequate treatment. Computed tomography (CT) imaging features of clear cell renal cell carcinoma (ccRCC) may contribute to personalized risk assessment. Purpose To assess the correlation between CT imaging features and Fuhrman grade of ccRCC, and to identify the predictors of high Fuhrman grade in conjunction with tumor size. Material and Methods CT scans of 169 patients with 173 pathologically proven ccRCCs were retrospectively reviewed in consensus by two radiologists for the presence of intratumoral necrosis and intratumoral cyst and tumor size. Histologic grade was classified as either low (Fuhrman grade I or II) or high (Fuhrman grade III or IV). Statistical significance was evaluated by using univariate, multivariate regression, receiver operating characteristic (ROC) curve, and Spearman correlation analyses. Results On CT, 20 of the 173 tumors had intratumoral cysts, 60 had intratumoral necrosis, and 93 showed entirely solid tumors. The odds of high grade were higher with intratumoral necrosis and entirely solid tumor than with intratumoral cyst ( P < 0.03). Intratumoral necrosis showed a significantly high odds ratio of 25.73 for high Fuhrman grade. The ROC curve showed a threshold tumor size of 36 mm to predict high Fuhrman grade for overall tumors (area under the ROC curve, 0.70). In ccRCCs with intratumoral necrosis or cyst, tumor size did not significantly correlate with Fuhrman grade. Conclusion Intratumoral necrosis on CT was a strong and independent predictor of biologically aggressive ccRCCs, irrespective of tumor size.

Effects of inappropriate empirical antibiotic therapy on mortality in patients with healthcare-associated methicillin-resistant Staphylococcus aureus bacteremia: a propensity-matched analysis.

BACKGROUND: The purported value of empirical therapy to cover methicillin-resistant Staphylococcus aureus (MRSA) has been debated for decades. The purpose of this study was to evaluate the effects of inappropriate empirical antibiotic therapy on clinical outcomes in patients with healthcare-associated MRSA bacteremia (HA-MRSAB). METHODS: A prospective, multicenter, observational study was conducted in 15 teaching hospitals in the Republic of Korea from February 2010 to July 2011. The study subjects included adult patients with HA-MRSAB. Covariate adjustment using the propensity score was performed to control for bias in treatment assignment. The predictors of in-hospital mortality were determined by multivariate logistic regression analyses. RESULTS: In total, 345 patients with HA-MRSAB were analyzed. The overall in-hospital mortality rate was 33.0 %. Appropriate empirical antibiotic therapy was given to 154 (44.6 %) patients. The vancomycin minimum inhibitory concentrations of the MRSA isolates ranged from 0.5 to 2 mg/L by E-test. There was no significant difference in mortality between propensity-matched patient pairs receiving inappropriate or appropriate empirical antibiotics (odds ratio [OR] = 1.20; 95 % confidence interval [CI] = 0.71-2.03). Among patients with severe sepsis or septic shock, there was no significant difference in mortality between the treatment groups. In multivariate analyses, severe sepsis or septic shock (OR = 5.45; 95 % CI = 2.14-13.87), Charlson's comorbidity index (per 1-point increment; OR = 1.52; 95 % CI = 1.27-1.83), and prior receipt of glycopeptides (OR = 3.24; 95 % CI = 1.08-9.67) were independent risk factors for mortality. CONCLUSION: Inappropriate empirical antibiotic therapy was not associated with clinical outcome in patients with HA-MRSAB. Prudent use of empirical glycopeptide therapy should be justified even in hospitals with high MRSA prevalence.