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1.
We report the results of 322 ultrasonically guided percutaneous fine-needle biopsies of focal intrahepatic lesions. The technique is original in several respects; it is an aspiration of both the lesion and normal-looking liver, and it includes both cytology and histology when the tiny cores are obtained. Cytology included Papanicolaou and Giemsa staining and other special staining when necessary. Sensitivity was 88.6% and specificity was 100% in the diagnosis of malignancy. Out of 141 metastases, 14 false negatives, 5 misclassifications, and 122 correct diagnoses were obtained. Out of 69 hepatomas the correct diagnosis of malignancy was made in 63 patients and of these the correct classification in 49. Complications occurred in six patients and marked hemorrhage in four. This technique is a simple, accurate, safe method for the diagnosis of focal intrahepatic lesions.  相似文献   
2.

Background  

Skin and soft tissue infections are increasingly prevalent clinical problems, and it is important for health care practitioners to be well trained in how to treat skin abscesses. A realistic model of abscess incision and drainage will allow trainees to learn and practice this basic physician procedure.  相似文献   
3.
Using microtechniques, total removal of acoustic neuromas with facial nerve preservation is possible today in most cases. The next barrier of operative treatment is hearing preservation which is routinely attempted, with the help of intraoperative brainstem auditory evoked responses monitoring. The present series deals with 176 operations performed sub-occipitally in 159 patients from 1970 up to 1985. Twelve patients were operated upon 29 times. According to the W.T. Koos classification, there were 16 type II, 39 type III and 121 type IV neuromas. Ten patients died postoperatively. In seven of these, death was related to surgery, in two it was caused by respiratory failure. In the last patient unexplained sudden death occurred. 169 patients had no facial weakness preoperatively, in 158 of these the facial nerve was anatomically preserved (93.5%). Facial nerve function was judged by evaluation of function of face at least 12 months after operation. Up to 36 months after surgery, a good facial result may be expected in cases where the facial nerve was macroscopically spared at completion of removal. Functional results have been reviewed in 151 patients according to the J.W. House's International Evaluation System, with an excellent or good result in 66 (44%), fair in 65 (43%), bad or poor in 20 (13%). The anatomical preservation of the cochlear nerve could be achieved in 80 patients of the group of 169 in whom the auditory function had not been damaged by a previous operation. In fact, the auditory function preservation could be reasonably attempted in 79 patients: showing a hearing loss below 70 dB on tone audiometry, whatever may be the result of speech discrimination score. 59 patients (75%) of this later group had their auditory nerve preserved, 14 (18%) showed preserved hearing function postoperatively, 10 of these with a speech discrimination score over 50%. Two of these showed an improvement of preoperative hearing, two others showed a total recovery of hearing function after removal.  相似文献   
4.
PURPOSE: In France, legislation mandates that the clinical diagnosis of brain death be confirmed by one paraclinical test before organ donation is allowed. That test may be either the electroencephalogram (EEG) or cerebral angiography. We report a case in which the clinical diagnosis of brain death was first confirmed by two EEGs performed according to the French guidelines, but ruled out by cerebral angiography. Considering that the EEG is no longer recommended to establish the diagnosis of brain death, we discuss the relevance of maintaining the EEG for brain death diagnosis in France. CLINICAL FINDINGS: A 58 yr-old man was admitted to the intensive care unit because of coma secondary to a massive subarachnoid hemorrhage with herniation below the falx shown by computed tomography. Clinical criteria of brain death were rapidly present. Two EEGs first confirmed the diagnosis but a four-vessel cerebral angiography was finally performed because the patient moved spontaneously. This cerebral angiography showed flow in the right internal carotid artery. A computed tomography performed the next day definitely confirmed the absence of brain death and organ donation did not occur. CONCLUSIONS: This case demonstrates the limitations of the EEG for this indication and suggests that angiography should be preferred. French legislation is probably maladjusted and would benefit by incorporating guidelines of other countries like Canada. International harmonization of criteria for brain death diagnosis would also be welcome.  相似文献   
5.
6.
Intrahepatic portal venous variations: prevalence with US.   总被引:8,自引:0,他引:8  
M Atri  P M Bret  M A Fraser-Hill 《Radiology》1992,184(1):157-158
A prospective ultrasound study was undertaken to determine the prevalence of variants of the intrahepatic branching of the portal venous system. Of the 507 patients examined, 55 (10.8%) had trifurcation, 24 (4.7%) had a right posterior segmental branch arising from the main portal vein, 22 (4.3%) had a right anterior segmental branch originating from the left portal vein, and one (0.2%) had absence of the horizontal segment of the left portal vein. Not one patient had complete absence of the right portal vein in this series. The remaining 405 (79.9%) patients had normal distribution of the portal venous system; some patients of the normal group had minor variations in distribution.  相似文献   
7.
Characterization of poorly differentiated neoplasms can be a challenging task for the surgical pathologist. It is essential that the entire spectrum of immunomorphologic findings of various tumors be recognized to avoid improper characterization of a given neoplasm, which may in turn adversely affect patient management. Tumor characterization is complicated by the immunomorphologic transformations that malignant cells may undergo by virtue of which they may depart from expression of expected features and acquire new, unexpected characteristics. Traditionally, amelanotic melanomas have been difficult to characterize because of the diversity of their light microscopic morphology (epithelioid, spindle, and combined varieties). As a result, several other neoplasms are usually considered in the differential diagnosis. This report describes a primarily spindle-cell amelanotic melanoma that created a diagnostic dilemma, which could only be resolved by combining the information obtained from extensive evaluation by means of several diagnostic techniques. This case also stresses the phenotypic heterogeneity of the cytoskeleton of malignant melanomas and therefore their varied immunomorphologic characteristics.  相似文献   
8.
9.

Purpose

This study examined the acute time course of effects of extracorporeal shock wave lithotripsy (ESWL)1 on renal hemodynamics in anesthetized minipigs with and without pretreatment with verapamil.

Materials and Methods

We applied ESWL (2000 shocks, 24 kV, unmodified Dornier HM3), to the right kidneys of isoflurane-anesthetized female pigs. Urine flow and renal hemodynamics were monitored from each kidney via ureteral balloon catheters. Arterial blood pressure and bilateral urine flow, glomerular filtration rate (GFR, inulin clearance) and renal plasma flow (RPF, para-aminohippurate clearance) were monitored for 45 minutes before ESWL, and at 1, 4 and 24 hours after ESWL.

Results

Treatment with ESWL consistently caused unilateral hematuria and subcapsular renal hematomas in the shocked kidneys and significantly reduced GFR and RPF in those kidneys at 1 and 4 hours after ESWL. Urine flow was reduced through 24 hours in the shocked kidneys. Renal plasma flow, but not GFR, was significantly reduced in the contralateral (unshocked) kidneys at 1 and 4 hours after ESWL to the other kidneys. Verapamil blunted the ESWL-induced reductions of urine flow, GFR and RPF in the shocked kidneys and eliminated the reduction of RPF in the unshocked kidneys.

Conclusions

These experiments demonstrate that ESWL to 1 kidney acutely impaired hemodynamics in both kidneys and that verapamil attenuated the response in the shocked kidneys and eliminated it in the contralateral unshocked kidneys.  相似文献   
10.
Tentorial Meningiomas. Report on Twenty-Seven Cases   总被引:14,自引:0,他引:14  
Summary ? Objective. Report our experience with 27 tentorial meningiomas (TM) surgically treated between 1985 and 1998.  Methods. The records of 27 patients with TMs were retrospectively reviewed for clinical presentation, neuroradiological evaluation, surgical treatment and long-term outcome. The extent of tumor resection was scored according to the Simpson's grading for tumor removal. Long-term results were evaluated according to the Glasgow Outcome Score (GOS).  Results. The average age was 53 years. Female predominance was 74%. The most common complaints at presentation were headaches (51%), gait ataxia (33%), memory disturbances (30%) and hypo-acousia (30%). A classification of TMs into 5 subgroups according to tumor site is proposed on the basis of imaging studies. A cerebrospinal fluid shunt was established prior to direct approach in 7 patients and as the sole procedure in one inoperable patient. Twenty-seven direct approaches were undertaken in 26 patients, including 17 infratentorial and 10 supratentorial approaches. Total tumor removal was achieved in 20 patients (77%) and subtotal removal in 6 (23%). Fifteen patients (55%) experienced 22 postoperative complications. One patient died three months after a subtotal resection (mortality=3,7%). With a mean follow-up of 54 months, all 26 survivors are currently alive with 23 having resumed their normal activities and 3 needing assistance. Five of 6 patients with subtotal resection survived and were followed for a period ranging from 72 to 132 months: none showed residual tumor progression and no re-operation was considered. An additional patient experienced a ?true? recurrence 6 years after total removal, with no tumor progression 2 years after his recurrence was recognized.  Discussion. The best surgical approach to TMs is still a controversial matter. The advantages and drawbacks of conventional versus transbasal approaches are reviewed. Our experience suggests that subtotal removal can be associated with long recurrence-free intervals and preserved quality of life. TMs located at the tentorial edge carried a definitely worse prognosis than peripheral forms.  相似文献   
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