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11.
Non-invasive tear break-up time (NITBUT) has been proposed as a measure of tear film integrity which is superior to the more commonly used tear break-up time (TBUT), since it does not alter the volume or the physicochemical properties of the tear layer by the addition of fluorescein. We measured NITBUT by measuring the time taken for distortions or discontinuities to appear in the reflected image of a grid pattern which covered about 80 per cent of the corneal surface. NITBUT measures were made 100 times on seven Hong Kong Chinese subjects with up to 20 consecutive measures being made on a single day. We also measured NITBUT on one occasion on an unselected population of 52 Hong Kong Chinese subjects. NITBUT shows a skewed distribution in all subjects, with many shorter values and some extremely long values. There are statistically significant variations in NITBUT from day to day, and from subject to subject. The group of 52 subjects also had a skewed NITBUT distribution with many short values and some very long values. The arithmetic mean does not adequately represent NITBUT data, either for individual subjects or for this group of subjects. As many as five to eight measures may be necessary to gain a stable estimate of the NITBUT and stability of the measure is improved if extreme values are omitted. We recommend the use of nonparametric statistics to compare NITBUT values from day to day in or between subjects.  相似文献   
12.
A retrospective review was done of 69 children and adolescents (7-17 years old) who underwent 75 arthroscopies of the knee during a 5-year period. Girls were overrepresented (71%). Thirty-eight were children under the age of 16. Of 46 injuries, 34 (74%) happened during sports. Children and adolescents were divided into two age groups based on their presumed state of skeletal maturity (boys 9–15 and girls 7–14 in group I and boys 16–17 and girls 15–17 in group II); meniscal lesions were equally common in the two groups, whereas anterior cruciate ligament tears were more common in older children (NS). Eleven of 17 (65%) anterior cruciate ligament lesions were combined with other intra-articular pathology, most often meniscal tears (9/11). As in other studies, half of the prearthroscopic diagnoses were incorrect. A high frequency of incorrect prearthroscopic diagnoses and of combined lesions justifies arthroscopy as an important diagnostic tool in children and adolescents with a history of twisting knee injury or chronic nonspecific knee problems. Girls practising ball games seem to be especially prone to knee injuries leading to arthroscopy.  相似文献   
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The patient is placed in lateral decubitus. A 6-cm incision made in the axilla allows access to the latissimus dorsi tendon and its neurovascular pedicle. Holding the arm in internal rotation, the surgeon detaches sharply the tendon off the humeral shaft and then reinforces it with wrapping sutures. Pulling the free limbs of the sutures exposes the under surface of the muscle and helps to identify the neurovascular pedicle. Special lighting retractors suited for a large diameter scope are helpful. Mobilization is completed when 2 cm of the tendon crosses the posterior edge of the acromion. The standard lateral portal is used for visualization. A silicon drain tube stiffened by a Wissinger rod is advanced from the posterior portal under direct visualization in the space between teres minor and deltoid, exiting in the auxiliary incision. A suture loop passed down the tube retrieves the tendon sutures out the posterior portal. These are then moved out the anterior portal, thus pulling the tendon over the tuberosity. The first anchor is inserted at the anterior aspect of the greater tuberosity, close to the articular cartilage and long head of the biceps tendon. Two to 3 anchors are inserted fixing the tendon to the tuberosity until it is stable.  相似文献   
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16.
Background: As in many parts of the world, the Schirmer tear test is the main test used by optometrists in Saudi Arabia for assessing adequacy of tear production. Variability of the test has been reported in different ethnic groups but not in Arabs. This paper looks at the mean and repeatability of the values obtained by the Schirmer test in a normal Arab population Method: The test was performed on the right eyes of 23 young adult Saudi male subjects at five visits over two weeks. Result: Results showed that for each subject the test values were not repeatable, varying widely over the period of evaluation. The mean value was estimated at 10.6 mm and the 95 per cent confidence limits were 7.9 and 13.3 mm. It was also established that the greater the amount of tears, the greater the variability. Conclusion: This study supports the claim that the Schirmer test is not repeatable and hence is unreliable. Therefore, caution should be exercised in employing it for clinical diagnosis. (Clin Exp Optom 1995; 78: 5: 190–193)  相似文献   
17.
目的研究采用自体静脉管套入吻合口并注入脑细胞生长肽的方法,对面神经损伤后功能恢复的影响.方法吻合神经断端后用自体静脉管套入吻合口并注入脑细胞生长肽.分析肌电图和观察表情肌功能恢复,比较两种方法对损伤的面神经功能恢复的影响.结果自体静脉管套入吻合口并注入脑细胞生长肽的方法,比传统方法表情肌功能恢复时间明显缩短,且一期修复比二期修复功能恢复时间明显缩短,差异具有非常显著性意义(P<0.01).两种方法修复面神经损伤,表情肌功能恢复后检测面神经传导速度差异无显著性意义(P>0.05).结论自体静脉管套入吻合口并注入脑细胞生长肽的方法是一种比较有前途的面神经修复方法.  相似文献   
18.
Arthroscopic repair of rotator cuff tears is now possible. By using the biomechanical principles of margin convergenceand the balance of force couples, even large cuff defects can be repaired. Suture anchors are particularly suitable for arthroscopic repairs, and a corkscrew anchor design lends itself to a trans-tendon approach  相似文献   
19.
Summary Two patients with complete paralysis of the axillary nerve are reported on. One case is well documented. In both cases there was very good functional adaptation, resulting from hypertrophy of the rotator cuff so that there was only a slight or no loss of movement. The rotator cuff should therefore be exercised at an early stage when there is isolated axillary nerve damage. The function of the supraspinous muscle is also discussed.   相似文献   
20.
Ultrasonography of rotator cuff tears: a review of 500 diagnostic studies   总被引:1,自引:0,他引:1  
Ultrasonography of the rotator cuff has been shown to be of value in diagnosing rotator cuff tears. This report summarizes our experience with our first 500 diagnostic examinations. All patients were examined in the hyperextended internal rotation view with commercially available high-resolution real-time ultrasound equipment. Patients were diagnosed as having a rotator cuff tear if a focal echogenic lesion or a defect within the rotator cuff was identified. This study confirmed the value of ultrasonography for the diagnosis of rotator cuff tears. Accuracy, sensitivity, and specificity all exceeded 90%, and correlated with surgical findings. This was better than arthrography in the same patient population. Ultrasound is an accurate noninvasive method of examining the rotator cuff for the presence of tears. We suggest that rotator cuff ultrasonography is the procedure of choice for the diagnosis of tears if adequate instrumentation is available.  相似文献   
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