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61.
Nieuwenhuis EJ van der Waal I Leemans CR Kummer A Pijpers R Castelijns JA Brakenhoff RH Snow GB 《Head & neck》2005,27(2):150-158
BACKGROUND: In patients with head and neck squamous cell carcinoma (HNSCC), the presence of lymph node metastases is the most important prognosticator. Sentinel node (SN) biopsy has been shown to be an accurate staging technique for patients with breast cancer and melanoma and might also be suited for patients with HNSCC. This study was undertaken to determine whether the SN concept holds true for HNSCC and could be exploited for SN biopsy. METHODS: In 22 patients with T2 to T4 N0 oral or oropharyngeal squamous cell carcinoma (SCC) who were scheduled to undergo combined primary tumor excision and elective unilateral (n = 17) or bilateral (n = 5) neck dissection, SN identification was performed the day before surgery by use of lymphoscintigraphy after peritumoral injections of 99mTc-labeled colloidal albumin. After the neck dissection specimens were removed, all SNs, all other radioactive lymph nodes, and all nonradioactive lymph nodes were retrieved for histopathologic analysis, including serial sectioning at 250-microm intervals and immunohistochemical analysis (IHC). RESULTS: Overall, in 21 (78%) of 27 neck sides, an SN was identified by scintigraphy. Of the six neck sides in which SNs were not identified by scintigraphy, four were from three patients who underwent bilateral neck dissection. In another patient treated by bilateral neck dissection, the SN identified by scintigraphy could not be found in the specimen. In the remaining 20 neck dissection specimens, 23 SNs and 30 additional radioactive lymph nodes could be found. At histologic examination of the 20 neck specimens in which the SN was found, at least one SN was tumor positive in eight cases. In one neck specimen, a metastasis was detected in a nonradioactive lymph node, whereas the SN was tumor free, also at serial sectioning and IHC. In the remaining 11 neck sides in which the SN was tumor negative, none of the other radioactive (n = 13) and none of the nonradioactive (n = 279) lymph nodes contained tumor at histopathologic analysis, including serial sectioning and IHC. The sensitivity of the SN procedure for predicting lymph node metastases, therefore, was 89% (eight of nine neck specimens) when an SN was identified by scintigraphy and found in the specimen. The overall accuracy of the SN procedure for predicting the presence or absence of lymph node metastases in the neck was 95% (19 of 20 neck specimens). CONCLUSIONS: Our study seems to validate the SN hypothesis for oral and oropharyngeal cancer. The role of SN biopsy in the management of the N0 neck in such patients has yet to be established through prospective trials. SN identification (and thus biopsy) does not seem to be reliable in patients with tumors located in or close to the midline. 相似文献
62.
F Kummer 《The Thoracic and cardiovascular surgeon》1983,31(6):329-330
Cardiopulmonary function is a determinant of the utmost importance in thoracic surgery. A large battery of tests is available, however, only a relatively limited part of it is obligatory. The essential procedures include testing of global ventilation (inspiratory vital capacity, FEV1), relation of lung volumes (residual volume) and regional quantitation of perfusion (scan). Other costly and invasive tests can be regarded as complementary. This is true in planned lung resection for cancer, where the indication for surgery is of vital importance. Other types of thoracic surgery need a more precise evaluation of risk factors balanced against the expected general improvement of cardiopulmonary function, as in cardiac surgery, decortication, and resection of bullae. But since thoracic surgery is practised mainly for the purpose of lung resection with ensuing loss of function, major attention is paid to this field in order to avoid inconclusive but costly testing, and to discuss indication and use of involved technique in high-risk patients. 相似文献
63.
In 16 patients with severe chest injuries the pulmonary function was evaluated as early as possible. Special emphasis was laid upon the basic criteria for the indication of an early decortication in cases of organized hematothorax. A follow-up study of ten patients, who were treated conservatively and of six patients, who underwent decortication, showed that the inspiratory and exspiratory reserve volume and the compliance of the lung were the most reliable criteria. They showed, if a traumatic disturbance of the lung function was reversible or irreversible. It seems that patients improve faster after decortication. If, however, signs of a quick spontaneous recovery of the lung function is seen, there is no indication for surgery. 相似文献
64.
Severe hypoxaemia was present in four patients with instability of the traumatised chest. After operative correction of the instability there was a spontaneous normalization of pO2 in 3 patients without the need of artificial ventilation. In one patient with preexisting broncho-pulmonary disease, a brief period of controlled ventilation resulted in an even more rapid normalization of blood-gas values. Due to operative correction of chest instability after severe trauma, the need for artificial ventilation seems to be greatly diminished. 相似文献
65.
Ellerkmann RM McBride AW Dunn JS Bent AE Blomquist JL Kummer LG Melick CF 《American journal of obstetrics and gynecology》2004,190(4):1034-1038
OBJECTIVE: The purpose of this study was to compare anticipatory and postprocedure pain perception in female patients who undergo multichannel urodynamic evaluation in an office setting. STUDY DESIGN: One hundred consecutive patients completed a visual analogue pain scale before and after urodynamic testing. RESULTS: The mean postprocedure pain score of 2.32 cm was significantly lower than the anticipatory pain rating of 4.35 cm (P<.05). The lower postprocedure pain score was not influenced by previous hysterectomy, body mass index, menopausal status, estrogen replacement therapy, or analgesic or psychiatric medication usage. Patients who had undergone previous anti-incontinence surgery reported significantly higher levels of pain during the procedure (mean visual analogue pain scale score, 3.10 cm vs 2.06 cm; P=.027). CONCLUSION: Patients who undergo urodynamic testing anticipate higher degrees of discomfort than they perceive during the procedure. Previous anti-incontinence surgery appears to lower the pain threshold. 相似文献
66.
In order to measure errors in pin positions, a tibia with referenced pin insertions was radiographed in various locations using a mini C-arm. Changes in pin position locations up to seven millimeters and twelve degrees were found. To minimize these errors, limbs should be centered and parallel to the plane of the imaging screen of the C-arm. If possible, pin insertions should be made in this plane. Magnification due to the distance from the screen should be determined for precise pin positioning. 相似文献
67.
OBJECTIVES: The anterior curvature of the femur affects intramedullary nail insertion, revision prosthesis design, and the biomechanics of the proximal femur. Two previous studies, using small numbers of femurs, determined femoral curvature and showed that it was significantly greater than that of the several intramedullary nails they evaluated. In this study, the curvature of 948 femurs (474 matched pairs) was determined and compared with current intramedullary nails. The correlation of femoral curvature to age, gender, femoral size, and race was also evaluated. SETTING: Museum skeletal collections and a hospital biomechanics laboratory. METHODS: The curvature of 892 femurs (446) from the skeletal collections of 2 museums was measured by processing the digital images of the femurs with a computer curve-fitting program. Fifty-six additional, embalmed femurs (28 pairs) from our collection were also digitally imaged and then radiographed and their medullary curvatures similarly determined for comparison. Curvatures of 8 current antegrade intramedullary nails and 3 long-stemmed femoral hip prostheses were obtained from manufacturers and confirmed by measurements from their templates after digitization. RESULTS: We found the average femoral anterior radius of curvature was 120 cm (+/- 36 cm). There was no effect of age on femoral curvature nor was there a correlation between femoral width or femoral length to curvature. Black donor femurs had less curvature than white donor femurs (P < 0.001). There was close correlation (r = 0.967) between the femoral curvatures determined from the digital images and the radiographs. Radii of curvature of the intramedullary nails ranged from 186 to 300 cm (eg, straighter than the femurs). CONCLUSIONS: There was a large mismatch between the curvature of some current antegrade intramedullary nails and the average femur. Although this is only 1 factor affecting nail insertion, the mismatch warrants a reappraisal of these intramedullary nail designs. CLINICAL RELEVANCE: Because ease of intramedullary nail insertion and possibility of cortical comminution are determined by a number of factors including insertion point and fracture location, it appears that a decrease in radii of curvature (less straight) of current nail designs is warranted, particularly for those larger diameter nails designed for hip fracture stabilization that have greater rigidity due to design or material. 相似文献
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