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21.
This retrospective study summarizes our experience based on treating 62 patients with trigeminal neuralgia treated with microvascular decompression. All patients had typical trigeminal neuralgia symptoms, with 24 of them (38%) having failed to benefit from other previous treatment paradigms. We excluded subjects with atypical and/or secondary forms of trigeminal neuralgia. Follow-up duration ranged from 5 months to 10 years 6 months, with recurrence being identified in three patients (4.8%).We found that the superior cerebellar artery is the leading offending vessel in our cases (33.9%; 21 patients). Interestingly, seven patients (11.3%) underwent an early reoperation 12-48 h later after the first operation was deemed ineffective. This subgroup recovered satisfactorily following isolation of the pathogenic vessels. Overall, no mortality was observed in our patients, and the only permanent morbidity outcome was a case of facial nerve palsy (1.6%). We conclude that microvascular decompression and its reapplicaiton for patients who showed no pain relief immediately after the first decompression are safe and effective treatments for trigeminal neuralgia.  相似文献   
22.
Disorders of elbow extension occur following traumatic or neurologic injuries of the triceps muscle. Restoration of elbow extension is an integral part of the entire upper extremity surgical reconstruction to improve the following daily activities: bringing down an object from above, handwriting, using the hand in the supine position, steering a wheelchair, driving a car, and swimming. The transfer of the posterior head of the deltoid muscle to triceps (Moberg procedure) and the transfer of the biceps to triceps (Friedenberg procedure) are previously described procedures for the functional restoration of triceps function. In conditions where these procedures cannot be used, we describe a new technique for restoration of elbow extension. In 4 cases with obstetrical palsy sequela, where shoulder abduction was established with the latissimus dorsi and teres major transfer, restoration of elbow extension was planned to aid in activities performed while the hand is above the head. To achieve this goal, the brachioradialis muscle was transposed bipedically to the triceps muscle.  相似文献   
23.
Today, laparoscopic donor nephrectomy (LDN) in many centers features the standard approach for kidney retrieval in living donors. More than 60% of the centers in the USA currently perform LDN and numbers are rising in Europe as well. Today's variety of laparoscopic approaches reflects the evolution in the field of LDN. Multiple modifications have been made for the laparoscopic approach, with consequences for intraoperative handling of the kidney, operating and ischemic times and with impact on donor, organ, and recipient. We reviewed the literature from 1995 to 2004 and critically evaluated the different technical modifications, their specific advantages and disadvantages and their impact for the operation. The article aims to help the surgeon choose the technique he feels most safe with for performing laparoscopic kidney retrieval safely and with good results for donor and recipient.  相似文献   
24.
HYPOTHESIS: We hypothesized that surgical treatment would improve respiratory muscle strength in symptomatic hyperparathyroidism (HPT). DESIGN: Prospective clinical trial. SETTING: A tertiary referral center. PATIENTS: Fifteen consecutive patients with symptomatic HPT and 10 with euthyroid multinodular goiter (control group) without a history of obstructive or restrictive lung disease. INTERVENTIONS: Forced vital capacity and forced expiratory volume in 1 second were measured before and 6 months after surgery to estimate respiratory muscle involvement. These measurements were compared with the reference values estimated individually in each patient. Mann-Whitney and Wilcoxon signed rank tests were used for statistical analysis, and P<.05 was considered statistically significant. MAIN OUTCOME MEASURES: Respiratory dysfunction in patients with symptomatic HPT, pulmonary function after parathyroidectomy, and the correlation between the preoperative serum parathyroid hormone and total serum calcium values and the impairment in pulmonary function. RESULTS: Preoperative forced vital capacity and forced expiratory volume in 1 second measurements were below the reference values in 11 (73%) and 9 (60%) patients, respectively. All the patients were normocalcemic, and forced vital capacity and forced expiratory volume in 1 second measurements significantly improved at postoperative month 6 (P = .001). No significant difference was detected in the control group. Improvement in pulmonary function correlated with preoperative serum calcium and parathyroid hormone values in patients with HPT (P<.05 and P<.001, respectively). CONCLUSIONS: Symptomatic HPT impairs inspiratory and expiratory components of respiratory function, and normalization of serum calcium levels after surgical treatment is associated with a significant improvement in lung function.  相似文献   
25.
Although various posterior insertion angles for screw insertion have been proposed for C1 lateral mass, substantial conclusions have not been reached regarding ideal angles and average length of the screw yet. We aimed to re-consider the morphometry and the ideal trajections of the C1 screw. Morphometric analysis was performed on 40 Turkish dried atlas vertebrae obtained from the Department of Anatomy at the Medical School of Ankara University. The quantitative anatomy of the screw entry zone, trajectories, and the ideal lengths of the screws were calculated to evaluate the feasibility of posterior screw fixation of the lateral mass of the atlas. The entry point into the lateral mass of the atlas is the intersection of the posterior arch and the C1 lateral mass. The optimum medial angle is 13.5 ± 1.9° and maximal angle of medialization is 29.4 ± 3.0°. The ideal cephalic angle is 15.2 ± 2.6°, and the maximum cephalic angle is 29.6 ± 2.6°. The optimum screw length was found to be 19.59 ± 2.20 mm. With more than 30° of medial trajections and cephalic trajections the screw penetrates into the spinal canal and atlantooccipital joint, respectively. Strikingly, in 52% of our specimens, the height of the inferior articular process was under 3.5 mm, and in 70% was under 4 mm, which increases the importance of the preparation of the screw entry site. For accommodation of screws of 3.5-mm in diameter, the starting point should be taken as the insertion of the posterior arch at the superior end of the inferior articular process with a cephalic trajection. This study may aid many surgeons in their attempts to place C1 lateral mass screws.  相似文献   
26.

Background/Purpose

Perfusion imaging redefines computed tomography (CT) as a technique that can now depict vascular physiology in addition to detailed anatomy. The major clinical applications of perfusion CT are in acute stroke and oncology. Currently, there are very limited data on the application of perfusion CT in urology. The aim of the present study is to investigate the potential value of perfusion CT in anatomic and functional evaluation of obstruction in a single session on experimental hydronephrosis model in rats. Thus, we evaluate the perfusion CT in a new clinical application.

Methods

Twenty-eight rats were randomly allocated into 4 groups each consisting of 7 rats. At the third week of experimental intervention, postoperative renogram curves and perfusion parameters of the right kidneys' cortex and pelvis were assessed by CT. The right ureter was sutured as proximal complete obstruction in group 1, as distal complete obstruction in group 2, and as proximal partial obstruction in group 3. Group 4 served as the sham control group. Computed tomography was performed with single-slice tomography. Dynamic examination was performed with the help of perfusion software through contrast-enhanced tomography examination.

Results

In all study groups, the aorta time/density curves showed a rapid increase after a rapid decrease, and the duration to reach peak concentration in the normal kidney cortex was observed to be later than the aorta as expected. In groups 1, 2, and 3, the duration to reach peak concentration lengthened and the peak concentration values decreased. The time/density curves gradually increased as a result of the accumulation of the contrast agent in the pelvis, and a peak was observed at the end of the procedure in all study groups. In groups 1, 2, and 3, a statistically significant decrease (P = .01, P = .01, and P = .01, respectively) was observed in the peak concentration values of the contrast agent in comparison to group 4. The flow and blood volume values gradually decreased as the grade of the obstruction increased and the localization of the obstruction or grade of obstruction moved closer to the kidney.

Conclusion

In conclusion, perfusion CT technique, performed in a single session, is a useful method for anatomic visualization, together with functional evaluation, in the diagnosis of ureteric obstructive pathology of experimental hydronephrosis model.  相似文献   
27.
28.
PURPOSE: To determine the incidence of venous thromboembolism (VTE) after removal of retrievable inferior vena cava (IVC) filters. MATERIALS AND METHODS: Retrospective study was conducted of 67 patients who underwent 72 consecutive filter retrievals at a single institution. Data collected included VTE status at the time of filter placement, anticoagulant medications at the time of filter retrieval and afterward, new or recurrent VTE after filter removal, and insertion of subsequent filters. Patient questionnaires were completed in 50 cases, chart review in all patients. RESULTS: At the time of filter placement, 30 patients had documented VTE, 19 had a history of treated VTE, and 23 were at risk for but had neither previous nor present VTE. Mean duration of follow-up after filter removal was 20.6 months +/- 10.9. A total of 52 patients (57 filters) received anticoagulation and/or antiplatelet medications after filter removal. There were two documented episodes of recurrent deep vein thrombosis (2.8% of filters removed), both in patients who had VTE at the time of filter placement and underwent therapeutic anticoagulation at the time of filter removal. One of these patients (1.4% of filters removed) also experienced pulmonary embolism. Of the 23 patients without VTE when the filter was placed, none developed VTE after filter removal. Four patients (5.5% of filters removed) required subsequent permanent filters, three for complications of anticoagulation, one for failure of anticoagulation. CONCLUSIONS: VTE was rare after removal of IVC filters, but was most likely to occur in patients who had VTE at the time of filter placement.  相似文献   
29.
BACKGROUND: The primary goal of ultrasonography (US) in the evaluation of a thyroid nodule is to determine its malignancy, although the diagnosis of a malignant nodule on the basis of US alone is nearly impossible. The aim of this prospective study was to evaluate the predictive value of sonographic features in the preoperative diagnosis of malignant thyroid nodules, and to determine the important features of sonography. METHODS: This prospective study included 550 consecutive patients with , thyroid nodules. Nodules were divided into two groups on the basis of pathological diagnosis: group 1 consisted of 1,633 nodules with a benign pathology, and group 2 consisted of 293 nodules with a malignant pathology. RESULTS: Microcalcifications, blurred nodular margins, and solid and hypoechoic appearance were more common in malignant nodules compared to benign nodules (89.1% versus 5%; 64.5% versus 4.7%; 81.6% versus 30.6% ; and 62.5% versus 43.1%, respectively; p < 0.001). There was a positive correlation between the detection of malignant thyroid nodules and microcalcification (rs = 0.791, p = 0.0001), blurred nodular margin (rs = 0.625, p = 0.0001), solid appearance (rs = 0.376, p = 0.0001), and hypoechoic appearance (rs = 0.141, p = 0.0001). Microcalcifications, blurred nodular margins, and solid and hypoechoic appearance were independent determinants of malignancy upon US examination of thyroid nodules (OR: 159, OR: 37, OR: 9.9, and OR: 2.2, respectively). CONCLUSION: Although we did not identify a single feature indicative of malignancy in the sonographic examination of nodules, microcalcification and blurred margin were the strongest correlates for malignancy.  相似文献   
30.
The lateral recess is one of the main compression sites in lumbar spinal canal stenosis. Lumbar nerve root is mainly entrapped by bony tissue in compression syndrome. The patient has a long history of back pain in conjunction with claudication symptoms. Besides laminotomy and facetectomy techniques, several specific surgical approaches to treat the lateral recess stenosis have been described. The surgical technique of bilateral lateral recess decompression via subarticular fenestrations used in this study is a less invasive technique, which enables to decompress the neural structures while preserving as much of the bony structures and ligamentum flavum as preferred. In 16 patients, we measured lateral recess heights with computerized tomography. The number of involved lumbar segments was one in 11 patients and two in 5 patients. The visual analogue scale (VAS) results were maintained before, 3 and 12 months after the operation. All patients benefited from the operations. Mean VAS scores were 7.0, 5.5, and 4.0, respectively. There were not any surgery-related complications. Mean follow-up period is 22.6 months. The surgical technique described and used in this study provides easy access to every zone of lateral recess and is safe and effective in treating the lumbar lateral recess stenosis syndrome.  相似文献   
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