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91.
Pancreas divisum (PD) is a congenital anomaly present in 6-10% of the population. Computed tomography (CT) examinations in eight of 15 patients (53%) with endoscopic retrograde pancreatography (ERCP)-proven PD were interpreted as showing enlargement of the pancreatic head. Two of these had carcinoma, three had pancreatitis limited to the ventral pancreas, and three were normal. Criteria to distinguish nonpathologic enlargement of the pancreatic head due to PD alone from pathologic causes may include homogeneous parenchyma and an absence of other abnormal signs on CT. Because PD may simulate a pancreatic head mass, the radiologist should be familiar with this variant, and ERCP should precede biopsy unless other evidence of malignancy is present.  相似文献   
92.
A case of hepatocellular carcinoma with neoplastic invasion of the inferior vena cava is presented. Computed tomograms before and after injection of contrast medium revealed an unusual density enhancement of the wall of the invaded portion of the vena cava. This sign is correlated with an angiographic sign of venous invasion present in our case.  相似文献   
93.
94.

Background

Scrotal trauma includes all injuries of the testicular parenchyma and scrotal envelopes. It is a surgical emergency, affecting mainly adolescent.

Objectives

To answer two questions, diagnostic value of ultrasound, and indication of surgical treatment in this type of trauma.

Methodology

Retrospective study of 16 patients with testicular trauma, treated between January 2004 and December 2009 in unit of surgical emergency in the Children's Hospital of Rabat.

Results

Attitude of service is the medical treatment and anti-inflammatory drugs when there is no clinical or ultrasonographic signs of severity, surgical exploration is indicated when serious testicular lesions are suspected. Among our 16 patients, 12 underwent surgery, five after open trauma and three after conducting an ultrasound. Four of our patients underwent a clinical and ultrasonographic observation. The average follow-up was 3 years, and the rate of testicular atrophy in our series is 6.25%.

Conclusion

Testicular trauma is an emergency requiring adequate and early care. Ultrasound should not delay surgical exploration of any traumatic haematocele in order to preserve the testicle.  相似文献   
95.
This study reports a family affected by a new phenotype associated with dilated cardiomyopathy and quadriceps myopathy. METHODS: 29 family members underwent a physical and neurological examination, including an electromyogram and biopsy of muscle abnormalities. A cardiac examination was performed in all subjects. RESULTS: The family pedigree (n=72) demonstrated that transmission was autosomal dominant. Eleven subjects had cardiac involvement, only four had quadriceps muscle involvement. Cardiac impairment preceded neurological involvement. The mean age for neurological involvement was 44+/-0.8 years (range 43-45) and cardiac involvement was 37+/-7.9 years (range: 24-45). Cardiac involvement consisted of: hypokinetic dilated cardiomyopathy (64%); atrial fibrillation (100%); ventricular arrhythmias (64%); impaired conduction with bundle branch or complete atrio ventricular block (73%). Four patients required pacemakers and anti arrhythmic therapies. Four patients died: two of refractory heart failure and two of sudden death; two patients were resuscitated following cardiac arrest. Three patients required a prophylactic implantable cardiac defibrillator (ICD). Muscle morphological abnormalities were characterized by a variable number of fibers with rimmed vacuoles. The quadriceps deteriorated progressively without impairment of other muscles. Genotypic study showed a lamin A/C gene mutation. CONCLUSIONS: This family was affected by a new phenotype composed of an autosomal dominant severe dilated cardiomyopathy with conduction defects or arrhythmias and quadriceps myopathy. Cardiac abnormalities preceded neuromuscular disorders and defined the prognosis of this disease.  相似文献   
96.
BACKGROUND. Efficient early diastolic filling is essential for normal cardiac function. Diastolic suction, as evidenced by a decreasing left ventricular pressure during early filling, could result from restoring forces (the release of potential energy stored during systolic deformation) dependent on myofilament relaxation. Although these restoring forces have been envisioned within individual myofibers, recent studies suggest that gross fiber rearrangement involving the connective tissue network occurs easy in diastole. This may lead to the release of potential energy stored during systole and suction-aided filling. METHODS AND RESULTS. To establish precisely the timing and extent of restoration of the systolic torsional deformation of the left ventricle with respect to early filling at baseline and with enhanced relaxation, we studied untwisting during control conditions and with catecholamine stimulation. Using noninvasive and nondestructive magnetic resonance tagging, torsional deformation of the left ventricle was measured at 20-msec intervals in 10 open-chest, atrially paced dogs, starting at aortic valve closure. Eight equiangular tags intersected the epicardium and endocardium in three short-axis imaging planes (base, mid, and apex). From the intersection points, epicardial and endocardial circumferential chord and arc lengths were measured and angular twist of mid and apical levels with respect to the base (maximal torsion and its reversal, untwisting) was calculated. Echo-Doppler provided timing of aortic valve closure and of mitral valve opening. Zero torsion was defined at end diastole. Torsion at the apical level reversed rapidly between its maximum and the time immediately after mitral valve opening: from 7.0 +/- 5.8 degrees to 3.2 +/- 5.4 degrees and 12.0 +/- 8.5 degrees to 6.9 +/- 7.8 degrees (mean +/- SD, both p less than 0.01) at the epicardium and endocardium, respectively. During the same period, no significant circumferential segment length changes occurred. As expected, after mitral valve opening, filling resulted in significant circumferential segment lengthening, whereas further reversal of torsion was small and nonsignificant. During dobutamine infusion, torsion at end systole was greater and reversal during isovolumic relaxation was much more rapid and greater in extent (p less than 0.01). Torsion reversed from 11.5 +/- 4.3 degrees to 5.7 +/- 4.8 degrees and 17.4 +/- 6.4 degrees to 6.9 +/- 7.7 degrees at epicardium and endocardium. CONCLUSIONS. Untwisting occurs principally during isovolumic relaxation before filling and is markedly enhanced in speed and magnitude by catecholamines. This partial return of the left ventricle to its preejection configuration before mitral valve opening could represent an important mechanism for the release of potential energy stored in elastic elements during the systolic deformation. These myocardial restoring forces would be markedly enhanced by physiological changes consequent to catecholamines such as during exercise, offsetting the concomitant shortening of the filling period.  相似文献   
97.
Dilated cardiomyopathy may be primary or secondary. Although some causes are well known, such as toxic substances (alcohol, chemotherapy...) or viral infections, biochemical abnormalities are much less common. The authors report the case of a 58 year old woman with no previous history admitted to hospital for an inaugural episode of cardiac failure. The ECG showed sinus tachycardia with a long QT interval (560 mm) and a dilated hypokinetic cardiomyopathy with a left ventricular ejection fraction of 20%. The aetiological investigation showed severe hypocalcaemia (0.66 mmol/L) related to primary hypoparathyroidism. This is an important cause to remember because its treatment leads to correction of the cardiac disease, usually within weeks.  相似文献   
98.
The solitary pulmonary nodule. Assessment, diagnosis, and management   总被引:13,自引:0,他引:13  
We have presented a brief overview of an approach that has been very successful in our hands in the patient with an SPN. Even though the patient who has undergone a thoracotomy is full of gratitude to his physician when told that the resected lesion was benign and does not question the need for the thoracotomy, we have met equally happy and gratified patients when they were told that their lesion is benign be it after CT densitometry or needle biopsy. When properly performed, these techniques demand care and attention to detail much like the surgeon performing a delicate procedure. Without proper care, these procedures can in fact reflect negatively on the physician performing them and fall in disrepute. CT densitometry and transthoracic needle aspiration biopsy allow effective management of the patient with an SPN with prompt documentation of both malignant or benign lesions. With the proper application of these techniques, the majority of patients with benign disease will not need a thoracotomy for diagnosis with resultant benefits to the patient as well as to third-party payers.  相似文献   
99.
Measurement of left ventricular (LV) mass by magnetic resonance imaging (MRI) is accurate in normal hearts. Because determination of mass by MRI does not require assumptions about ventricular shape, this method may be well suited for evaluating hearts distorted by infarction. To test this hypothesis, gated MRI was performed in 15 dogs before and after acute myocardial infarction. The LV mass of each dog was calculated from five short-axis images acquired at end systole, when shape distortion is greatest, at end diastole, and also from slices at varying phases of the cycle with a multiphase mode that required only one acquisition. Correlation was excellent between actual mass and end-systolic mass before infarction (p less than 0.001, r = 0.98, and SEE = 5.1 g) and after infarction (p less than 0.001, r = 0.97, and SEE = 6.6 g). Likewise, values correlated closely at end diastole before (p less than 0.001, r = 0.96, and SEE = 6.7 g) and after infarction (p less than 0.001, r = 0.94, and SEE = 8.7 g). Surprisingly, measurements of mass by a multiphase mode were also very accurate before (p less than 0.001, r = 0.98, and SEE = 5.1 g) and after (p less than 0.001, r = 0.95, and SEE = 6.49 g) infarction. Therefore, at the same phase and at multiphases of the cardiac cycle, MRI permits accurate determination of LV mass in distorted hearts.  相似文献   
100.
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