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M. Ferri A. Laghi† P. Mingazzini‡ F. Iafrate† L. Meli F. Ricci‡ R. Passariello† V. Ziparo 《Colorectal disease》2005,7(4):387-393
OBJECTIVE: Pre-operative staging of rectal cancer should identify patients with extrarectal spread, who might benefit from pre-operative radiotherapy, and patients with minimal sphincteral involvement, who can avoid permanent colostomy. The aim of this study was to assess the accuracy of Magnetic Resonance Imaging (MRI) to predict tumour stage and sphincter status. PATIENTS AND METHODS: Thirty-three patients with a rectal tumour were pre-operatively assessed by MRI with a phased-array coil. Imaging results were correlated with the final pathological findings. RESULTS: The overall accuracy of pre-operative staging with MRI was 88% (k = 0.75) for extramural tumour invasion and 59% (k = 0.26) for lymph node metastases. MRI correctly evaluated the infiltration of the anal sphincters in 87% of patients (7 of 8 patients with low rectal tumour). CONCLUSION: MRI provides the surgeon with valuable information regarding extramural tumour spread and sphincteral involvement, enabling appropriate selection of patients for pre-operative adjuvant therapy or sphincter-saving surgery. 相似文献
44.
The ability to compare various results that measure clinical deficits and outcome is a necessity for successful worldwide
discussion about cervical spondylogenic myelopathy (CSM) and its treatment. There is hardly any information in literature
how to value and compare outcome assessed by different scores. In a retrospective study we objectively evaluated the Nurick-score,
Japanese-orthopaedic-association-score (JOA-Score), Cooper-myelopathy-scale (CMS), Prolo-score and European-myelopathy-score
(EMS) using the data of 43 patients, all of whom showed clinical and morphological signs of CSM and underwent operative decompression.
The scores were assessed pre- and postoperatively. The correlation between the score-results, anamnesis, clinical and diagnostic
data was investigated. All the scores show a statistically significant correlation and measure postoperative improvement.
With exception of the Prolo-score all scores reflect clinical deficits of CSM. The Prolo-score rates the severity of CSM on
the state of the economic situation above clinical symptoms. The main differences of the scores are shown in the number of
patients showing postoperative improvement, varying between 33% (Nurick-score) and 81% (JOA-score). The recovery-rates, as
a measure of the cumulative improvement of all the symptoms, show less variation (23–37%). The differences of the recovery-rate
were only statistically significant between JOA-score, Nurick-score and EMS (P < 0.05), whereas all the other scores showed no significant differences. To assess the postoperative successes, the evaluation
of the recovery-rate is essential. There is no significant difference in the recovery-rate amongst the majority of the scores,
which allows a good comparison of the results from different studies. Nevertheless, it is always important to differentiate
the therapy results of CSM published worldwide. 相似文献
45.
Molecular staging of head and neck squamous carcinoma 总被引:3,自引:0,他引:3
The staging system of head and neck cancer is a Tumor-Node-Metastases system that was developed by the American Joint Committee on Cancer. The stage of the head and neck cancer defines the extent of the lesion and is determined by physical examination, radiologic studies, and pathologic examination. Accurate staging of head and neck cancer is critical since it will determine the treatment modalities used to cure the disease. Recent advances in the field of molecular genetics have allowed clinicians to detect occult cancer cells previously missed by physical examination and standard histopathologic techniques. Molecular assays are 500 times more sensitive in identifying cancer cells than standard techniques and provide more objective analyses with fewer sampling errors. Consequently, these techniques are currently being used to perform molecular staging of head and neck cancer patients. Preliminary results show that molecular staging will accurately identify those patients at significantly increased risk for recurrence of their head and neck cancer. 相似文献
46.
M. Baekelandt M. Kockx F. Wesling & J. Gerris 《International journal of gynecological cancer》1993,3(2):65-71
An extensive review of the currently available literature on primary fallopian tube carcinoma is presented. The role of vaginal ultrasonography and the importance of an aggressive evaluation of every tubal deformity is stressed. A staging system which takes into account recent data on the biology of this malignancy is proposed. We emphasize the largely underestimated importance of early lymphatic spread of this disease, necessitating a thorough staging laparotomy with pelvic and para-aortic lymph node sampling in the apparent early stages. The need for adjuvant treatment is obvious, but until now no firm data exist as to what the optimal strategy should be. We recommend that until more representative studies are available, ovarian carcinoma protocols should be used in clinical practice. 相似文献
47.
Digital subtraction arthrography in preoperative evaluation of painful total hip arthroplasty 总被引:1,自引:0,他引:1
A. Z. Ginai F. C. van Biezen P. A. M. Kint H. Y. Oei W. C. J. Hop 《Skeletal radiology》1996,25(4):357-363
Objective. The objective of this clinical study was to define the diagnostic value of plain radiography, digital subtraction arthrography
and two-phase bone scintigraphy in patients with clinically loose or infected hip prostheses. Design. Digital subtraction arthrograms, scintigrams and plain radiographs of 70 consecutive patients who underwent revision hip arthroplasty
were scored individually and in masked fashion for the presence or absence of features indicating loosening of femoral and/or
acetabular components. The operative findings acted as the gold standard. Results. Digital subtraction arthrography was best (P<0.001) for predicting a loose acetabular component, while no significant additional predictive value was found for plain
radiographs (P=0.24) and scintigraphy (P=0.27). Digital subtraction arthrography was also the most important modality for predicting a loose femoral component (P=0.001), while the plain radiograph was of significant (P=0.04) additional value and scintigraphy was of no additional value (P=0.13) on multivariate analysis. Conclusion. Digital subtraction arthrography gives the best results in the prediction of loosening of acetabular and femoral components.
Plain radiographs give additional information on loosening of the femoral component, but scintigraphy offers no additional
advantage. 相似文献
48.
基于股骨正位X片的人工髋关节术前优选系统的研究 总被引:2,自引:0,他引:2
目的研究开发人工髋关节术前优选系统,为患者选择最优的人工髋关节。方法综合国内外人工髋关节选择的最新成果,对人工髋关节假体的形状尺寸特征进行了全面分析,结合股骨正位X片,制订了人工髋关节的选择原则,并进行几何和力学评价;使用MATLAB和VB混合编程开发人工髋关节术前优选系统。结果制订了优选准则与评价方法,开发人工髋关节术前优选系统。临床初步应用,已为患者成功进行了人工髋关节置换术。结论根据患者股骨正位X片及其股骨特征尺寸,该系统可以准确的为患者选择最优的假体。 相似文献
49.
A computer model was designed as a relational database to assess breast cancer screening in a cohort of women where the growth and development of breast cancer originates with the first malignant cell. The concepts of thresholds for growth, axillary spread, and distant sites are integrated. With tumor diagnosis, staging was performed that includes clinical and sub-clinical states. The model was parameterized to have staging characteristics similar to data published by the Surveillance, Epidemiology, and End-Results (SEER) Program. Validation was accomplished by comparing simulated staging results with non-SEER sources, and simulated survival with independent clinical survival data. 相似文献
50.
Early stages of chick somite development 总被引:17,自引:0,他引:17
We report on the formation and early differentiation of the somites in the avian embryo. The somites are derived from the mesoderm which, in the body (excluding the head), is subdivided into four compartments: the axial, paraxial, intermediate and lateral plate mesoderm. Somites develop from the paraxial mesoderm and constitute the segmental pattern of the body. They are formed in pairs by epithelialization, first at the cranial end of the paraxial mesoderm, proceeding caudally, while new mesenchyme cells enter the paraxial mesoderm as a consequence of gastrulation. After their formation, which depends upon cell-cell and cell-matrix interactions, the somites impose segmental pattern upon peripheral nerves and vascular primordia. The newly formed somite consists of an epithelial ball of columnar cells enveloping mesenchymal cells within a central cavity, the somitocoel. Each somite is surrounded by extracellular matrix material connecting the somite with adjacent structures. The competence to form skeletal muscle is a unique property of the somites and becomes realized during compartmentalization, under control of signals emanating from surrounding tissues. Compartmentalization is accompanied by altered patterns of expression of Pax genes within the somite. These are believed to be involved in the specification of somite cell lineages. Somites are also regionally specified, giving rise to particular skeletal structures at different axial levels. This axial specification appears to be reflected in Hox gene expression. MyoD is first expressed in the dorsomedial quadrant of the still epithelial somite whose cells are not yet definitely committed. During early maturation, the ventral wall of the somite undergoes an epithelio-mesenchymal transition forming the sclerotome. The sclerotome later becomes subdivided into rostral and caudal halves which are separated laterally by von Ebner's fissure. The lateral part of the caudal half of the sclerotome mainly forms the ribs, neural arches and pedicles of vertebrae, whereas within the lateral part of the rostral half the spinal nerve develops. The medially migrating sclerotomal cells form the peri-notochordal sheath, and later give rise to the vertebral bodies and intervertebral discs. The somitocoel cells also contribute to the sclerotome. The dorsal half of the somite remains epithelial and is referred to as the dermomyotome because it gives rise to the dermis of the back and the skeletal musculature. The cells located within the lateral half of the dermomyotome are the precursors of the muscles of the hypaxial domain of the body, whereas those in the medial half are precursors of the epaxial (back) muscles. Single epithelial cells at the cranio-medial edge of the dermomyotome elongate in a caudal direction, beneath the dermomyotome, and become anchored at its caudal margin. These post-mitotic and muscle protein-expressing cells form the myotome. At limb levels, the precursors of hypaxial muscles undergo an epithelio-mesenchymal transition and migrate into the somatic mesoderm, where they replicate and later differentiate. These cells express the Pax-3 gene prior to, during and after this migration. All compartments of the somite contribute endothelial cells to the formation of vascular primordia. These cells, unlike all other cells of the somite, occasionally cross the midline of the developing embryo. We also suggest a method for staging somites according to their developmental age. 相似文献