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991.
BackgroudThe rupture of the central slip of an extensor tendon of a finger causes a boutonniere (or buttonhole) deformity, characterized by pathologic flexion at the proximal interphalangeal (PIP) joint and hyperextension at the distal interphalangeal (DIP) joint. Currently, there are no standard treatment guidelines for this deformity. This study aimed to report clinical results of surgery to correct chronic boutonniere deformity.MethodsThis retrospective case series was conducted between January 2010 and December 2018 and only 13 patients with trauma-induced chronic deformity were included. After excision of elongated scar tissue, a direct anatomic end-to-end repair using a loop suture technique with supplemental suture anchor augmentation was conducted. Total active motion was assessed before and after surgery and self-satisfaction scores were collected from phone surveys.ResultsAll patients presented with Burton stage I deformities defined as supple and passively correctable joints. The initial mean extension lag of the PIP joint (43.5°) was improved by an average of 21.9° at the final follow-up (p < 0.001). The mean hyperextension of the DIP joint averaged 19.2° and improved by 0.8° flexion contracture (p < 0.001). The average total active motion was 220.4° (range, 160°–260°). Based on the Souter''s criteria, 69.2% (9/13) of the patients had good results. Only 1 patient reported fair outcome and 23.1% (3/13) reported poor outcome. The average Strickland formula score was 70 (range, 28.6–97.1). In total, 10 patients (77%) had excellent or good results. Of 10 patients contacted by phone, self-reported satisfaction score was very satisfied in 2, satisfied in 3, average in 3, poor in 1, and very poor in 1. Three patients reported a relapse of the deformity during range of motion exercises, 1 of whom underwent revision surgery. One patient complained of PIP joint flexion limitation, and 2 complained of DIP joint flexion limitation at final follow-up.ConclusionsIn chronic boutonniere deformity, central slip reconstruction with anchor suture augmentation can be an easily applicable surgical option, which offers fair to excellent outcome in 77% of the cases. The risk of residual extension lag and recurrence of deformity should be discussed prior to surgery.  相似文献   
992.

Objective

To compare observer performance using liquid-crystal display (LCD) and cathode-ray tube (CRT) monitors in the interpretation of soft-copy chest radiographs for the detection of small solitary pulmonary nodules.

Materials and Methods

By reviewing our Medical Center''s radiologic information system, the eight radiologists participating in this study (three board-certified and five resident) retrospectively collected 40 chest radiographs showing a solitary noncalcified pulmonary nodule approximately 1 cm in diameter, and 40 normal chest radiographs. All were obtained using a storage-phosphor system, and CT scans of the same patients served as the gold standard for the presence of a pulmonary nodule. Digital images were displayed on both high-resolution LCD and CRT monitors. The readers were requested to rank each image using a five-point scale (1 = definitely negative, 3 = equivocal or indeterminate, 5 = definitely positive), and the data were interpreted using receiver operating characteristic (ROC) analysis.

Results

The mean area under the ROC curve was 0.8901±0.0259 for the LCD session, and 0.8716±0.0266 for the CRT session (p > 0.05). The reading time for the LCD session was not significantly different from that for the CRT session (37.12 and 41.46 minutes, respectively; p = 0.889).

Conclusion

For detecting small solitary pulmonary nodules, an LCD monitor and a CRT monitor are comparable.  相似文献   
993.
PURPOSE: To evaluate the safety of adjuvant intravenous use of abciximab in balloon angioplasty for symptomatic middle cerebral artery stenosis. MATERIAL AND METHODS: Seven patients with symptomatic stenosis at the main trunk (n=5), or proximal post-trifurcation portion (n=2) of the middle cerebral artery, were enrolled in the study. A bolus dose of abciximab (0.15 mg/kg) was given intravenously immediately before the procedure. The immediate morphologic results as well as the presence of hyperacute thrombosis or hemorrhage after angioplasty were evaluated. Clinical evaluation was performed 1 day and 1 month following angioplasty. Oral antiplatelets were administered during the follow-up period. Follow-up angiography was performed after 7 to 14 (mean 10.4) months. Stenosis of a vessel greater than 50% was considered as restenosis. RESULTS: The procedure was technically successful in all patients. Immediate residual stenosis was insignificant in 4 and mild (less than 50%) in 3 patients. There was no evidence of intimal dissection. Mild gum bleeding was noted in two patients. All study patients were clinically stable at follow-up without newly developed neurological abnormality even though there was one case of occlusion and one case of restenosis on follow-up angiography. Angiographic patency rate was 71%. CONCLUSION: In performing proximal middle cerebral artery balloon angioplasty, abciximab may be safely used to prevent acute thrombosis. The mid-term patency of the vessels was also acceptable.  相似文献   
994.
OBJECTIVE: Our purposes were to determine whether a single application of radiofrequency energy to normal bone can create coagulation necrosis reproducibly and to assess the accuracy of MRI at revealing the extent of radiofrequency-induced thermal bone injury. MATERIALS AND METHODS: Using a 200-W generator and a 17-gauge cooled-tip electrode, a total of 11 radiofrequency ablations were performed under fluoroscopic guidance in the distal femurs of seven dogs. Radiofrequency was applied in standard monopolar mode at 100 W for 10 min. During radiofrequency ablation, the changes in impedance and currents were recorded. MRI, including unenhanced T1- and T2-weighted images and contrast-enhanced fat-suppressed T1-weighted images, was performed to evaluate ablation regions. Six dogs were killed on day 4 after MRI and one dog on day 7. RESULTS: In all animals, radiofrequency ablation created a well-defined coagulation necrosis and no significant complications were noted. The mean long-axis diameter and the mean short-axis diameter of the coagulation zones produced were 45.9 +/- 5.5 mm and 17.7 +/- 2.7 mm, respectively. At gross examination, thermal ablation regions appeared as a central, light-brown area with a dark-brown peripheral hemorrhagic zone, which was surrounded by a pale-yellow rim. On MRI, the ablated areas showed multilayered zones with signal intensities that differed from normal marrow on unenhanced images and a perfusion defect on contrast-enhanced T1-weighted images. The maximum difference between lesion sizes on MR images, established by measuring macroscopic coagulation necrosis, was 3 mm. The correlation between the diameter of coagulation necrosis and lesion size at MRI was strong, with correlation coefficients ranging from 0.89 for unenhanced T1-weighted images and 0.97 for unenhanced T2-weighted images to 0.98 for contrast-enhanced T1-weighted images (p < 0.05). CONCLUSION: Radiofrequency ablation created well-defined coagulation necrosis in a reproducible manner, and MRI accurately determined the extent of the radiofrequency-induced thermal bone injury.  相似文献   
995.
OBJECTIVE: The objectives of our study were to determine the incidence of filling defects in pulmonary arterial stumps on CT after pneumonectomy and to evaluate their radiologic and clinical significance. MATERIALS AND METHODS: We retrospectively reviewed 401 contrast-enhanced chest CT scans of 147 consecutive patients (male-female ratio, 123:24; mean age, 60 years) who underwent pneumonectomy (right, 60; left, 87) from 1996 to 2002 in our institution. CT findings were analyzed for the presence or absence of a filling defect in the vascular stump and its size, shape, and interval change on follow-up CT. CT findings were also evaluated for the length of the vascular stump and the presence of embolism in the contralateral pulmonary arteries, pneumonia, bronchopleural fistula, and bronchiolitis obliterans with organizing pneumonia. Intrathoracic or stump recurrence was also assessed in patients with lung cancer. The medical records of lung cancer patients were reviewed for the cause of pneumonectomy and stage and cell type of cancer at surgery. Statistical tests were performed to determine the relationship between the filling defect and other radiologic and clinical findings. RESULTS: A filling defect in the vascular stump was seen on CT scans of 18 patients after pneumonectomy (12%), and all had undergone the surgery for lung cancer. It was more frequently found in the right-sided stump (23.3%) than in the left-sided stump (4.6%) (p = 0.001). The vascular stump was longer in patients with a filling defect (37.2 +/- 6.8 [1 SD] mm) than those without this finding (25.0 +/- 12.5 mm) (p < 0.001). Other radiologic and clinical findings were not significantly related to the presence of the filling defect in the vascular stump. CONCLUSION: A filling defect in the pulmonary arterial stump seen on CT after pneumonectomy is thought to be an in situ thrombus caused by stasis of blood flow and is not related to pulmonary embolism, tumor recurrence, or other complications after pneumonectomy.  相似文献   
996.

Objective

To determine the feasibility of transcaval transjugular intrahepatic portosystemic shunt (TIPS) creation in patients with unusual anatomy between the hepatic veins and portal bifurcation, and inaccessible or inadequate hepatic veins.

Materials and Methods

Transcaval TIPS, performed in six patients, was indicated by active variceal bleeding (n=2), recurrent variceal bleeding (n=2), intractable ascites (n=1), and as a bridge to liver transplantation (n=1). The main reasons for transcaval rather than classic TIPS were the presence of an unusually acute angle between the hepatic veins and the level of the portal bifurcation (n=3), hepatic venous occlusion (n=2), and inadequate small hepatic veins (n=1).

Results

Technical and functional success was achieved in all patients. The entry site into liver parenchyma from the inferior vena cava was within 2 cm of the atriocaval junction. Procedure-related complications included the death of one patient due to hemoperitoneum despite the absence of contrast media spillage at tractography, and another suffered reversible hepatic encephalopathy.

Conclusion

In patients with unusual anatomy between the hepatic veins and portal bifurcation, and inaccessible or inadequate hepatic veins, transcaval TIPS creation is feasible.  相似文献   
997.
Objective To verify the usefulness of a fluoroscopy guided cervical interlaminar epidural steroid injection (CIESI) in patients with neck pain and cervical radiculopathy and to evaluate outcome predictors. Design We retrospectively analyzed 91 patients from July 2004 to June 2005 in whom CIESI was initially performed for neck pain and cervical radiculopathy. Therapeutic effects were evaluated 2 weeks after the administration of CIESI, and CIESI effectiveness was graded using a five-point scale, namely, whether the pain had disappeared, was much improved, slightly improved, the same, or aggravated. We also used a visual analog scale (VAS) for the clinical evaluation. According to documentation and follow-up charts, we categorized treatments as effective or ineffective. Possible outcome predictors, namely, diagnosis (spinal stenosis vs herniated disc), primary symptoms (neck pain vs radiculopathy vs both), age, gender, and duration of pain (more or less than 6 months) were also analyzed. Fisher’s exact test, the chi-square test, and multiple logistic regression analysis were used for the statistical analysis. Patients After their medical records had been reviewed, 76 patients were included in this study. Inclusion criteria were: the availability of a cross-sectional image, such as a CT scan or an MR image, and a follow-up record after injection. Results and conclusions The medical records of 76 patients (male:female = 41 : 35) of mean age 53.1 years (range 32 years to 82 years) were reviewed. Two weeks after injection, 55 patients (72.4%) had experienced effective pain relief. Patients with herniated discs had significantly better results than patients with spinal stenosis (86.1% vs 60.0%) (P < 0.05). Other non-significant predictors of an improved outcome included: a symptom duration of <6 months, a young age, and the presence of cervical radiculopathy. Multiple regression analysis showed that the only factor that was significantly associated with outcome was the cause of the pain, i.e., herniated disc or spinal stenosis. Fluoroscopy guided CIESI is a safe and effective means of treating patients with neck pain and cervical radiculopathy. The most important outcome predictor was cause of pain, and patients with herniated disc experienced better pain relief than those with spinal stenosis.  相似文献   
998.
Preoperative identification of significant coronary artery disease (CAD) in patients prior to valve surgery requires systematic invasive coronary angiography. The purpose of this current prospective study was to evaluate whether exclusion of CAD by multi-detector CT (MDCT) might potentially avoid systematic cardiac catheterization in these patients. Eighty-two patients (53 males, 62 ± 13 years) scheduled to undergo valve surgery underwent 40-slice MDCT before invasive quantitative coronary angiography (QCA). According to QCA, 15 patients had CAD (5 one-vessel, 6 two-vessel and 4 three-vessel disease). The remaining 67 patients had no CAD. On a per-vessel basis, MDCT correctly identified 27/29 (sensitivity 93%) vessels with and excluded 277/299 vessels (specificity 93%) without CAD. On a per-patient basis, MDCT correctly identified 14/15 patients with (sensitivity 93%) and 60/67 patients without CAD (specificity 90%). Positive and negative predictive values of MDCT were 67% and 98%. Performing invasive angiography only in patients with abnormal MDCT might have avoided QCA in 60/82 (73%). MDCT could be potentially useful in the preoperative evaluation of patients with valve disease. By selecting only those patients with coronary lesions to undergo invasive coronary angiography, it could avoid cardiac catheterization in a large number of patients without CAD. This work was supported by a grant of the Fondation Nationale de la Recherche Scientifique of the Belgian Government (FRSM 3.4557.02). Dr. Pouleur is supported by a personal grant of the Fondation Nationale de la Recherche Scientifique of the Belgian Government.  相似文献   
999.
OBJECTIVE: To ascertain the incidence of acute and chronic complications of aortic intramural hematoma (IMH) and to analyze the predictors of the development of each complication. MATERIALS AND METHODS: This retrospective study includes 107 consecutive patients diagnosed with aortic IMH by means of computed tomography (CT) during the period from January 1998 to December 2003 and followed up with serial CT examinations (median follow-up period, 320 days). There were 36 patients with type A and 71 with type B IMH. Initial and follow-up CT scans were reviewed, with special attention given to the development of complications, such as increase in the thickness of IMH, clinical and hemodynamic evolution requiring urgent surgery, and development of aortic dissection and/or aneurysm. If each complication developed within 30 days after the initial episode, we classified it as an acute complication; the others were classified as chronic complications. The time interval between the initial and the subsequent CT examination showing each complication was recorded. To identify the predictors of each complication, we analyzed the demographic and CT findings with regard to the following factors: age, sex, maximum thickness of the hematoma, maximum aortic diameter on initial CT examination, ulcerlike projection (ULP) on initial and follow-up CT examinations, and the degree of atherosclerosis. The Cox proportional hazards regression model with stepwise multivariate analyses was used to determine the significant predictors of each complication. RESULTS: Sixteen patients had acute complications consisting of aortic dissection (n = 7), aortic aneurysm (n = 6), and acute clinical and hemodynamic evolution requiring operation (n = 3). Three additional patients with aortic dissection (n = 1) and aneurysm (n = 2) underwent emergency surgery. Twenty-three patients with chronic complications had aortic dissection (n = 3), and aortic aneurysm (n = 20). Cox proportional hazards regression model revealed that the maximal diameter of involved aorta is the only significant predictor of the development of acute complications (P = 0.006), whereas the age (P = 0.040), type A IMH (P = 0.015), presence of ULP (P = 0.015), and newly developed ULP as revealed on follow-up CT examination (P = 0.032) were significant predictors of the development of chronic complications. With regard to the aortic dissection in 10 patients (9.3%; type A/B ratio, 5:5; median time interval, 34 days), Cox proportional hazards regression model revealed that the maximal thickness of the hematoma is the only significant predictor (P = 0.018). Twenty-one saccular and 5 fusiform aneurysms (24.3%) developed, as revealed on follow-up CT examinations (median time interval, 180 days). The presence of ULP (P = 0.030), type A (P = 0.038) and the maximal thickness of the hematoma (P = 0.017) were significant predictors for the development of an aneurysm. CONCLUSIONS: The maximum thickness of a hematoma on the initial CT is the significant factor predicting the development of aortic dissection and aortic aneurysm. Patients with type A IMH and ULP, as revealed by initial and short-term follow-up CT examinations, should be carefully followed up with subsequent CT examination to monitor the development of an aortic aneurysm, which is a relatively common chronic complication of IMH.  相似文献   
1000.
OBJECTIVE: To determine whether the computed tomographic (CT) findings of primary and recurrent combined hepatocellular-cholangiocarcinoma (HCC-CC) can predict the main tumor component on histopathologic examination, and to describe the recurrence patterns of HCC-CC after surgery. METHODS: Preoperative and postoperative CT findings of 12 HCC-CC patients who underwent curative surgery were retrospectively reviewed. The main features of the primary and recurrent tumors on CT and the pathological findings were classified as hepatocellular carcinoma (HCC)-dominant and cholangiocarcinoma (CC)-dominant groups. The concordance between the preoperative CT features and the initial pathological findings was evaluated using kappa statistics. The survival periods of the HCC-dominant and the CC-dominant group were compared using the Mann-Whitney U test. RESULTS: In 11 (91.7%) of 12 patients, the main CT features of HCC-CC were in strong agreement with main pathological findings (kappa = 0.824). The most common site of recurrence was the remnant liver. In 3 cases, only nodal metastasis was noted. The mean survival period was significantly longer in the HCC-dominant group than in the CC-dominant group of recurrent tumor (P = 0.016). CONCLUSIONS: Contrast-enhanced CT scanning can predict the dominant component of primary and recurrent HCC-CC. This capability can optimize treatment strategy for the patient with recurrent HCC-CC.  相似文献   
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