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A patient presented with malignant melanoma of the parotid gland with no obvious primary lesions, which was treated by total parotidectomy with excision of skin. Despite radiotherapy for brain metastases and combination chemotherapy for lung and lymph node metastases, she died 13 months after the initial operation.  相似文献   
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Little has been written about reconstructive methods after resection of melanomas in the head and neck region. We investigated reconstructive methods retrospectively related to the site and size of the melanomas resected by examining the medical records of 28 patients who had malignant melanomas of the head and neck resected at our hospital from 1984 to 2001. The tumour distribution was 12 in the cheek, 6 in the conjunctiva, 2 in the upper lip, 2 in the lower lip, one each in the lower eyelid, eyebrow, scalp, nose, and auricle. Reconstructive methods were 18 skin grafts, seven local flaps, and three free flaps. Three patients who had skin grafts required secondary reconstruction using free flaps. No local recurrences were observed. Reconstructions with local flaps give better aesthetical and functional results than free flaps and skin grafts. Immediate reconstruction with a flap is safe and it does not affect observation of local recurrences.  相似文献   
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Abstract Objectives: To propose a method for evaluating the reproducibility of anatomical coordinate systems based on craniofacial skeletal landmarks and to tentatively evaluate four systems created on preoperative cone-beam computed tomography (CBCT) data obtained from mandibular prognathism patients in order to confirm the utility for actual patients' data. Materials and Methods: In three-dimensional images of 10 patients obtained by a CBCT with a large field of view, six dentists set four coordinate systems that were created in different ways, twice by plotting some landmarks situated in the superior portion of the maxillofacial skeletons. The 95% confidence ellipse of six objective landmarks related to the jaw and teeth (upper incisor, left upper first molar, lower incisor, left lower first molar, menton, and left gonion) were three-dimensionally drawn for each coordinate system. The ellipsoid volume was calculated to evaluate the reproducibility of the coordinate systems. Results: The reproducibility could be evaluated for each coordinate system using the method proposed. The coordinate systems that were created by landmarks situated at greater distances from each other showed relatively small ellipsoid volume in comparison to those with shorter distances between landmarks. Conclusion: Anatomical coordinate systems with larger distances between the landmarks used were stable when landmarks related to the jaw and teeth were assigned as objective landmarks. The method proposed here was effective in terms of the reproducibility evaluation of a coordinate system.  相似文献   
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Objective: The purpose of the present exploratory study was to evaluate the effects of uncomplicated carotid endarterectomy (CEA) on cognitive function and brain perfusion in patients with unilateral asymptomatic severe stenosis of the internal carotid artery (ICA) by comparison with unoperated patients.

Methods: Patients with age ≤75 years and unilateral asymptomatic severe stenosis (≥70%) of the cervical ICA underwent CEA with antiplatelet therapy (surgically treated group: 116 patients) or antiplatelet therapy alone or neither (medically treated group: 45 patients). For the surgically treated group, neuropsychological testing and brain perfusion measurement using single-photon emission computed tomography were performed within one month before surgery and one month after surgery. For the medically treated group, the same testing and measurement were performed twice at an interval of 1 to 2 months.

Results: None of the operated patients developed new major ischemic events after surgery or intraoperative cerebral hyperperfusion. None of the patients in the medically treated group experienced neurological deficits including transient ischemic attacks during the study period. The incidence of patients with interval cognitive improvement was significantly greater in the surgically treated group (11 patients: 9%) than in the medically treated group (0%) (p = 0.0352). The incidence of patients with interval brain perfusion improvement in the ipsilateral cerebral hemisphere was significantly greater in the surgically treated group (24 patients: 21%) than in the medically treated group (0%) (p = 0.0003).

Conclusions: Uncomplicated CEA may improve cognitive function and brain perfusion in patients with unilateral asymptomatic severe stenosis of the ICA when compared with unoperated patients.  相似文献   
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