Accuracy of percutaneous pedicle screw placement with 3-dimensional fluoroscopy-based navigation: Lateral decubitus position versus prone position.

The accuracy of percutaneous pedicle screw (PSS) placement in the lateral decubitus position has seldom been reported. This study aimed to retrospectively compare the accuracy of PPS placement with 3-dimensional (3D) fluoroscopy-based navigation in 2 cohorts of patients who underwent surgery in the lateral decubitus or prone positions at our single institute. A total of 265 consecutive patients underwent spinal surgery with PPS from T1 (thoracic 1) to S (sacrum) under the 3D fluoroscopy-based navigation system at our institute. Patients were divided into 2 groups based on their intraoperative patient positioning: lateral decubitus (Group L) or prone (Group P). A total of 1816 PPSs were placed from T1 to S, and 76 (4.18%) PPSs were assessed as deviated PPS. Twenty-one of 453 (4.64%) PPSs in Group L deviation and 55 of 1363 (4.04%) PPSs in Group P had deviated PPS, but with not significant difference (P = .580). In Group L, although the PPS deviation rate was not significantly different between the upside and downside PPS, the downside PPS significantly deviated toward the lateral side compared with the upside PPS. The safety and efficacy of PPS insertion in the lateral decubitus position were similar to those in the conventional prone position.

The Prevalence and Characteristics of Diffuse Idiopathic Skeletal Hyperostosis (DISH): A Cross-Sectional Study of 1519 Japanese Individuals.

Background: Diffuse idiopathic skeletal hyperostosis (DISH) is a pathology characterized by enthesis ossification, but there have been few reports on epidemiological surveys. This report presents a cross-sectional survey of DISH from thoracic to sacral spine in patients at the tertiary emergency medical center. Methods: The patients were divided into DISH (+) group and DISH (−) group for a retrospective comparative study. The primary outcome measures were the frequency of DISH and the patient demographic data, the secondary outcome measures were the previous medical history (diabetes mellitus, cardiovascular disease), the extent of aortic calcification, the frequency of hyperostosis around the costovertebral joint and the mortality rate within 3 months of the initial examination. Results: This survey examined a total of 1519 patients. There were 265 cases (17.4%) in the DISH (+) group and 1254 cases in DISH (−) group. The prevalence of DISH was concentrated at the thoracolumbar junction, particularly at T9. The mean age, ratio of male and hyperostosis around the costovertebral joint were significantly higher in the DISH (+) group (p < 0.001), but there was no significant difference in other variables. Conclusions: The pathology of DISH might involve the effects of age-related changes or biomechanical effects.

The impact of the lateral decubitus position in the perioperative period on posterior fixation for thoracolumbar fracture with ankylosing spinal disorder.

OBJECTIVE: Patients with ankylosing spinal disorders (ASDs), such as ankylosing spondylitis and diffuse idiopathic skeletal hyperostosis, often have rigid kyphosis of the spine. The fracture site is sometimes unintentionally displaced when surgery is conducted with the patient prone. To prevent this incident, the authors adopted the lateral decubitus position for patients intraoperatively for this pathology. The aim of this study was to retrospectively assess the impact of the lateral decubitus position in the perioperative period on posterior fixation for thoracolumbar fractures with ASD. METHODS: Thirty-seven consecutive patients who underwent posterior instrumentation for thoracolumbar fracture with ASD at the authors' institute were divided into 15 lateral decubitus positions (group L) and 22 prone positions (group P). Surgical time, estimated blood loss (EBL), number of levels fused, perioperative complications, length of stay (LOS), ratio of fracture voids, and ratio of anterior wall height were investigated. The ratio of fracture void and the ratio of anterior wall height were the radiological assessments showing a degree of reduction in vertebral fracture on CT. RESULTS: Age, sex, BMI, fracture level, and LOS were similar between the groups. Levels fused and EBL were significantly shorter and less in group L (p < 0.001 and p = 0.04), but there was no significant difference in surgical time. The complication rate was similar, but 1 death within 90 days after surgery was found in group P. The ratio of fracture voids was 85.4% ± 12.8% for group L and 117.5% ± 37.3% for group P. A significantly larger number of patients with a fracture void ratio of 100% or less was found in group L (86.7% vs 36.4%, p = 0.002). The ratio of anterior wall height was 107.5% ± 12.3% for group L and 116.9% ± 18.8% for group P. A significantly larger number of patients with the anterior wall height ratio of 100% or less was also found in group L (60.0% vs 27.3%, p = 0.046). CONCLUSIONS: The results of this study suggest that the lateral decubitus position can be expected to have an effect on closing or maintaining the fracture void or a preventive effect of intraoperative unintentional extension displacement of the fractured site, which is often seen in the prone position during surgery for thoracolumbar fractures involving ASD.

Simultaneous Anterior and Posterior Release in Lateral Decubitus Position for Rigid Adult Spinal Deformity: A Technical Note and 2 Case Reports.

BACKGROUND: Correction surgery for rigid adult spinal deformity usually involves a complex 360° osteotomy, multiple intraoperative position changes, and staged surgery. Moreover, there is a lack of consensus regarding the surgical strategy for this pathology. We report the technical advantages of a simultaneous anterior and posterior release only in the lateral decubitus position to reduce surgical invasiveness in two case reports. CASE DESCRIPTION: A 76-year-old woman and an 80-year-old woman presented with significant spinal imbalance and segmental fusion in the anterior and posterior columns around the apex of the lumbar spinal curvature. We conducted this procedure for these patients at the first stage of spinal corrective surgery to achieve 360° osteotomy. A long posterior fusion surgery was performed after 1 week. The mean values of the central sacral vertical line, pelvic incidence minus lumbar lordosis, sagittal vertical axis, and pelvic tilt improved substantially postoperatively: central sacral vertical line, from 51.0 to 7.5 mm; pelvic incidence minus lumbar lordosis, from 27.5° to 0.5°, sagittal vertical axis, from 107.6 to 14 mm; pelvic tilt, from 34.0° to 13.0°. The mean surgical time and blood loss in the first- and second-stage operations were 242.1 minutes and 702 mL and 315.5 minutes and 549 mL, respectively, and no perioperative complications occurred. CONCLUSIONS: Simultaneous 360° segmental release in the lateral decubitus position without repositioning can make it possible to acquire satisfactory correction and reduce surgical invasiveness compared with the conventional procedure for adult spinal deformity.

Detecting MLC modeling errors using radiomics-based machine learning in patient-specific QA with an EPID for intensity-modulated radiation therapy.

PURPOSE: We sought to develop machine learning models to detect multileaf collimator (MLC) modeling errors with the use of radiomic features of fluence maps measured in patient-specific quality assurance (QA) for intensity-modulated radiation therapy (IMRT) with an electric portal imaging device (EPID). METHODS: Fluence maps measured with EPID for 38 beams from 19 clinical IMRT plans were assessed. Plans with various degrees of error in MLC modeling parameters [i.e., MLC transmission factor (TF) and dosimetric leaf gap (DLG)] and plans with an MLC positional error for comparison were created. For a total of 152 error plans for each type of error, we calculated fluence difference maps for each beam by subtracting the calculated maps from the measured maps. A total of 837 radiomic features were extracted from each fluence difference map, and we determined the number of features used for the training dataset in the machine learning models by using random forest regression. Machine learning models using the five typical algorithms [decision tree, k-nearest neighbor (kNN), support vector machine (SVM), logistic regression, and random forest] for binary classification between the error-free plan and the plan with the corresponding error for each type of error were developed. We used part of the total dataset to perform fourfold cross-validation to tune the models, and we used the remaining test dataset to evaluate the performance of the developed models. A gamma analysis was also performed between the measured and calculated fluence maps with the criteria of 3%/2 and 2%/2 mm for all of the types of error. RESULTS: The radiomic features and its optimal number were similar for the models for the TF and the DLG error detection, which was different from the MLC positional error. The highest sensitivity was obtained as 0.913 for the TF error with SVM and logistic regression, 0.978 for the DLG error with kNN and SVM, and 1.000 for the MLC positional error with kNN, SVM, and random forest. The highest specificity was obtained as 1.000 for the TF error with a decision tree, SVM, and logistic regression, 1.000 for the DLG error with a decision tree, logistic regression, and random forest, and 0.909 for the MLC positional error with a decision tree and logistic regression. The gamma analysis showed the poorest performance in which sensitivities were 0.737 for the TF error and the DLG error and 0.882 for the MLC positional error for 3%/2 mm. The addition of another type of error to fluence maps significantly reduced the sensitivity for the TF and the DLG error, whereas no effect was observed for the MLC positional error detection. CONCLUSIONS: Compared to the conventional gamma analysis, the radiomics-based machine learning models showed higher sensitivity and specificity in detecting a single type of the MLC modeling error and the MLC positional error. Although the developed models need further improvement for detecting multiple types of error, radiomics-based IMRT QA was shown to be a promising approach for detecting the MLC modeling error.

Probucol and the cholesterol synthesis inhibitors simvastatin and triparanol regulate I ks channel function differently.

Channels responsible for slowly activating delayed-rectifier potassium current (I(Ks)) are composed of KCNQ1 and KCNE1 subunits, and these channels play a role in the repolarization of cardiac action potentials. Recently, we showed that the antihyperlipidemic drug probucol, which induces QT prolongation, decreases the I(Ks) after 24-h treatment. In the present study, we investigated the effects of three cholesterol-lowering agents (probucol, an enhancer of cholesterol efflux; simvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor; and triparanol, a 3ß-hydroxysterol-▵24-reductase inhibitor) on cholesterol synthesis, the KCNQ1 current (I KCNQ1), and the I(Ks) to clarify the differences in the modes of action of these agents on the I(Ks). Probucol did not inhibit cholesterol synthesis and had no effect on I KCNQ1, while I(Ks) decreased after 24-h treatment. Simvastatin inhibited cholesterol synthesis and decreased I KCNQ1 and I(Ks). Additionally, the activation kinetics of I(Ks) became faster, compared with that of control I(Ks). Triparanol inhibited cholesterol synthesis but did not reduce I KCNQ1 and I(Ks). However, the activation kinetics of I(Ks) became faster. Our data indicated that the mechanism by which probucol inhibits I(Ks) was not mediated by the inhibition of cholesterol synthesis but depended on an interaction with the KCNQ1/KCNE1 complex. Meanwhile, the reduction in cholesterol induced by simvastatin and triparanol is one of the mechanisms that affects the kinetics of I(ks).

Flutamide-induced hepatic dysfunction in relation to steady-state plasma concentrations of flutamide and its metabolites.

The frequency, severity, and outcome of flutamide-induced hepatic injury were prospectively evaluated in 55 patients with prostate cancer who received 125 mg of flutamide 3 times a day (daily dose: 375 mg) combined with an agonistic analogue of luteinizing hormone-releasing hormone. In addition, we examined plasma and urine concentrations of flutamide and its major metabolites 4 weeks after the beginning of flutamide therapy, and evaluated their significance in predicting flutamide-induced hepatic dysfunction. Hepatic function could be assessed in 50 patients and hepatic dysfunction during therapy was observed in 9 patients (18%); 3 patients (6%) were classified as having moderate liver dysfunction and 6 (12%) were classified as having mild liver dysfunction. The steady-state plasma levels of flutamide and its biologic active metabolite, hydroxyflutamide (OH-Flu), were not related to hepatic dysfunction. However, the concentration of another major metabolite, 4-nitro-3-(trifluoromethyl)phenylamine (FLU-1) was considerably higher in 2 patients who developed clinically significant hepatic dysfunction. These findings suggest that clinically significant hepatic dysfunction could be induced in patients with compromised flutamide metabolism, which leads to a high concentration of FLU-1. Based on results of this study, we propose that plasma FLU-1 levels are one of the predictive factors for flutamide-induced hepatic dysfunction. This hypothesis will be confirmed in a large-scale study.

Xanthogranulomatous cystitis.

Xanthogranulomatous cystitis (XC) is a rare benign chronic inflammatory disease of unknown etiology. Herein we report a case of a 70-year-old woman who presented with frequent, postmicturition pain and lower abdominal discomfort. Cystoscopy revealed a mass at the dome of the bladder near the left wall. Enhanced computed tomography (CT) demonstrated a mass with a central cavity. The patient underwent partial cystectomy because the presence of bladder neoplasm could not be ruled out. She had has no recurrence of XC 29 months after the operation. The present case of XC is the 20th to be reported in the world.

[Carcinoma of urachus: report of 15 cases and review of literature--is total cystectomy the treatment of choice for urachal carcinoma?].

PURPOSE: This study was undertaken to determine the most appropriate type of operation for the improvement of the radical cure rate and QOL of patients with urachal cancer. We assessed the association between the stage, type of operation, and prognosis of cases we experienced and those reported in Japan. PATIENTS AND METHOD: The subjects included 15 cases of urachal cancer we have experienced in the past 14 years. While clarifying the clinical patterns of these cases, the association between stage, type of operation, and prognosis was studied. Of the cases of urachal cancer reported in Japan in the recent 20 years, 75 cases in which the stage, type of operation, and prognosis were documented were selected, and the association between the stage and outcome in each type of operation was studied. RESULTS: In regard to stage, all the cases were rated as more than IIIA. As for prognosis, 9 cases (60%) are alive without cancer at the present time with a mean survival time of 7 years. Of the above patients, 3 underwent cystectomy and 6 underwent en bloc segmental resection (herein after referred to en bloc). Recurrence or cancer death was experienced in 5 patients, 2 of which were classified as stage IIIA and 3 as IIID. Of these patients, one underwent en bloc, 3 partial resection of the bladder, and one underwent exploratory laparotomy. As far as our study of the cases reported in Japan is concerned, the prognosis of the cases having undergone only partial resection of the bladder was poor, while of the cases having undergone en bloc or total cystectomy 88-100% were alive without cancer for more than 2 years if their stage was classified as IIIA or below. On the other hand, prognosis was very poor whatever the type of operation in the cases whose cancer was stage IIIC or above. CONCLUSIONS: It appears that the en bloc is most appropriate as the type of operation for the cases of urachal cancer and that the application of total cystectomy is limited to some cases. In performing the en bloc, an extensive resection of the peritoneum, resection of the posterior sheath of the rectus muscle of the abdomen, and dissection of the intrapelvic lymph nodes in addition to the conventional types of operation should be carried out positively.

[Decrease in anticoagulant factors in patients with prostate cancer treated with diethylstilbestrol diphosphate].

PURPOSE: Estrogen has been highly evaluated as one of the most potent endocrine agents for the treatment of prostate cancer. Unfortunately, a high risk of cardiovascular complications is a clinically important adverse effect of estrogen therapy, and occasionally the complications are fatal. In recent years a high incidence (55%) of thrombotic events has been reported in patients with congenital protein S (PS) deficiency. The aim of this study is to determine the relationship between cardiovascular complications of estrogen therapy and anticoagulant factor levels in the serum of patients with prostate cancer. MATERIALS AND METHODS: Study 1 employed 99 patients with prostate cancer: 39 were untreated, 25 were treated with LH-RH agonist therapy alone, and 35 were treated with oral diethylstilbestrol diphosphate (DESdP) 300 mg per day. We measured the serum levels of anticoagulant factors, parameters antithrombin III (ATIII), protein C (PC), PS, coagulant and fibrinolytic factors in all patients. In study 2, the adverse effects of DESdP therapy on the serum levels of anticoagulant factors were examined in 8 patients with advanced prostate cancer. RESULTS: In study 1, the ATIII and PS levels of the patients treated with estrogen therapy were significantly lower than those in either the untreated patients or the patients treated with an LHRH agonist alone. Especially, both PS antigen (51.5 +/- 16.0%) and PS activity (42.9 +/- 16.0%) were markedly lower in estrogen-treated patients than in the untreated patients (102 +/- 20.8%, 100.6 +/- 20.7%, respectively) or the patients treated with an LH-RH agonist alone (97.9 +/- 16.8%, 91.5 +/- 17.7%, respectively, both p < 0.0001). PS was decreased to below the normal lower limit of normal in 82% (24/35) of the patients on estrogen therapy. In study 2, all 8 cases showed a significant decrease in PS after DESdP therapy. CONCLUSIONS: Our results showed that the PS levels in the oral DESdP group were almost the same as in patients with congenital PS deficiency. We conclude that decreased PS may play a role in the development of cardiovascular complications in prostate cancer patients on estrogen therapy.

[Clinical study of bladder injury].

Since bladder injury has no specific clinical symptoms, accurate diagnosis at first consultation is relatively difficult. To elucidate the clinical characters type of injury, clinical symptoms, laboratory findings, methods of therapy and diagnosis, we reviewed 15 patients with bladder injury over a 9-year-period 1990-1998 (10 were traumatic injuries and 5 spontaneous injuries). We found no specific clinical symptom of bladder injury. Bladder injury may occur anywhere in the bladder wall, but most commonly occurred at the dome of the bladder (60.0%). Gross hematuria was not seen in 40.0% of the cases. The accuracy of diagnosis at first consultation was relatively low (46.7%) and the tendency to make a misdiagnosis as acute abdomen on digestive organs was found. Of the traumatic injuries 60% were afflicted in the drunken state, so alcohol intoxication was considered as an important enviromental factor of bladder injury. Surgical repair of injury sites was employed in 11 cases (73.3%: 7 were intraperitoneal injuries, 4 were extraperitoneal injuries), 4 cases were managed with indwelling urethral catheter. With appropriate treatment, the prognosis is excellent.

[A case of adrenocortical carcinoma with masculinization, obtaining long prognosis with surgical treatment alone].

A 28 year-old woman presented right upper abdominal pain. She had been pointed out her masculinization and amenorrhea. CT scan and magnetic resonance imaging showed right adrenal tumor. In the endocrinological study, the serum cortisol and testosterone was elevated. Transabdominal right adrenalectomy and nephrectomy was carried out and histopathological diagnosis was adrenocortical carcinoma. The masculine symptom had disappeared after the operation and she has been without recurrence for five years.