Magnetic resonance imaging in the evaluation of inflammatory lesions in muscular and soft tissues: an experimental infection model induced by Candida albicans.

We have developed an experimental model to monitor inflammatory lesions in muscle and soft-tissues during the different stages of the disease by means of Magnetic Resonance Imaging (MRI). MRI of mice legs infected with Candida albicans was performed by standard two-dimensional spin echo and fast spin echo (RARE) using customized coils. The MRI findings were compared with pathologic examinations at the initial acute and established acute inflammatory stages, which provided accurate and detailed information on the evolution of the processes involved. The yeast caused inflammation within the first hours post-inoculation, appearing on T2-weighted images as an inhomogeneous mass with increased signal intensity. The presence of fungal hyphae was observed as hypointense signal areas in both T2 and T1 weighted images, with histologic confirmation. Areas of decreased signal intensity on T2 weighted images were apparent on the last experimental day and were attributed to the granulation tissue located within the capsule surrounding the abscess. The close correlation found between MRI and histopathology suggests that MRI is an ideal radiologic technique for monitoring the clinical and therapeutic follow-up of fungal infections in muscle and soft tissues.

Eosinophilic gastroenteritis: diagnostic laparoscopy.

We report a case of eosinophilic gastroenteritis. The initial diagnosis was made by laparoscopic inspection of the lesion during exploration of the abdomen. We immediately carried out an extracorporeal resection using a laparoscopic surgical technique. Pathological examination confirmed our diagnosis. Eosinophilic gastroenteritis is an infrequent condition, and this definitive description of a lesion as seen in the magnified field of the laparoscope demonstrates the effectiveness of laparoscopy as a diagnostic tool to diagnose the cause of ill-defined abdominal discomfort with inconclusive laboratory findings that formerly would have needed a more surgically aggressive laparotomy to resolve.

Hepatic abscesses: MR imaging findings.

PURPOSE: To determine magnetic resonance (MR) imaging features that characterize hepatic abscesses. MATERIALS AND METHODS: Clinical records and MR studies of 18 patients with proved hepatic abscesses were evaluated. The abscesses were pyogenic in 15 patients, fungal in two patients, and amebic in one patient. RESULTS: A total of 122 lesions were identified. Most were round (n = 114) with sharp borders (n = 99), hypointense on T1-weighted images (n = 73), and very hyperintense on T2-weighted images (n = 88). After injection of gadopentetate dimeglumine in 43 lesions, all 43 enhanced with sharp margins and 37 showed rim enhancement. All abscesses followed up diminished in size (50 of 50), and perilesional edema resolved before the central cavity did. CONCLUSION: MR imaging findings seen in hepatic abscesses include high signal intensity on T2-weighted images (72%) and perilesional edema (43 of 122 [35%]). Rim enhancement (86%) and increased conspicuity (35 of 43 [81%]) were found after injection of gadopentetate dimeglumine.

CT in local recurrence of rectal carcinoma.

OBJECTIVE: We evaluated the effectiveness of CT in detecting the recurrence of rectal cancer. MATERIALS AND METHODS: As part of a postoperative follow-up protocol, periodic CT examinations were performed on 67 patients who had had potentially curative surgery for rectal carcinoma. Retrospectively we evaluated the CT of these patients. In 21 patients there was local tumoral recurrence, which was detected by CT in 15. We classified the patients into two groups according to the surgical technique employed: anterior resection (AR) or abdominoperineal resection (APR). RESULTS: The sensitivity of CT for the diagnosis of local recurrence was greater in patients with APR (12/13; S = 92%) than in those with AR (3/8; S = 37%). In each group there was one false-positive result--thus both groups showed a similar specificity (94% in APR and 96% in AR). In the APR group, 38% of the recurrences (5/13) were detected initially by CT. Computed tomography was not the first diagnostic test in any of the recurrences after AR. CONCLUSION: On the basis of these results, we think that CT is a good diagnostic test for local recurrence in patients with rectal cancer and APR.

[Registration with piezoelectric sensors of the in vivo activity of right ventricular contractile elements in acute experimental pulmonary stenosis]. / Registro con sensores piezoeléctricos de la actividad "in vivo" del elemento contráctil del ventrículo derecho en estenosis pulmonares experimentales agudas.

Recordings with piezoelectric sensors of the variations of the contractile state due to severe acute pulmonary hypertension, provoked in intact canine hearts, are described. During the stenosis, a proportional increment of the isometric tension of the right ventricular wall and of the right atrial kick, due to the increasing difficulties for the respective blood contents evacuation of both cavities, were appreciated. Furthermore, lost of the right wall compliance, becoming more rigid, limited the systolic and diastolic pressure development of the right ventricle. Meanwhile, the piezoelectric sensor sutured on the left ventricular wall describes the consequent variations of the left ventricular contraction.

Registro con sensores piezoeléctricos de la actividad [quot ]in vivo[quot ] del elemento contráctil del ventrículo derecho en estenosis pulmonares experimentales agudas. / [Registration with piezoelectric sensors of the in vivo activity of right ventricular contractile elements in acute experimental pulmonary stenosis]

Recordings with piezoelectric sensors of the variations of the contractile state due to severe acute pulmonary hypertension, provoked in intact canine hearts, are described. During the stenosis, a proportional increment of the isometric tension of the right ventricular wall and of the right atrial kick, due to the increasing difficulties for the respective blood contents evacuation of both cavities, were appreciated. Furthermore, lost of the right wall compliance, becoming more rigid, limited the systolic and diastolic pressure development of the right ventricle. Meanwhile, the piezoelectric sensor sutured on the left ventricular wall describes the consequent variations of the left ventricular contraction.

[Recording, with piezoelectric sensors, of the activity of the contractile elements in vivo in experimental acute and chronic aortic stenosis]. / Registro con sensores piezoeléctricos de la actividad del elemento contráctil "in vivo" en estenosis aórticas experimentales agudas y crónicas.

Mechanic alterations of the left ventricular wall due to an increasing afterload by means of experimentally provoked acute and chronic aortic stenosis, registered by piezoelectric sensors sutured on the surface of the ventricle, are analyzed. Tension or force developed in the ventricular wall or the acceleration of the shortening velocity of the contractile element, under these conditions, show in the piezoelectric sensor curve a new characteristic contractile state depending on the rapidity and time elapsed since the aortic stenosis, making clear the diagnosis, systolic peaks and their evolutionary stage. Different adaptation mechanisms employed by the myocardium, according to the rapidity of the experimental stenosis, showed by means of the variations of the different phases of the cardiac cycle depicted by sensor curves, are also described.

Registro con sensores piezoeléctricos de la actividad del elemento contráctil [quot ]in vivo[quot ] en estenosis aórticas experimentales agudas y crónicas. / [Recording, with piezoelectric sensors, of the activity of the contractile elements in vivo in experimental acute and chronic aortic stenosis]

Mechanic alterations of the left ventricular wall due to an increasing afterload by means of experimentally provoked acute and chronic aortic stenosis, registered by piezoelectric sensors sutured on the surface of the ventricle, are analyzed. Tension or force developed in the ventricular wall or the acceleration of the shortening velocity of the contractile element, under these conditions, show in the piezoelectric sensor curve a new characteristic contractile state depending on the rapidity and time elapsed since the aortic stenosis, making clear the diagnosis, systolic peaks and their evolutionary stage. Different adaptation mechanisms employed by the myocardium, according to the rapidity of the experimental stenosis, showed by means of the variations of the different phases of the cardiac cycle depicted by sensor curves, are also described.

[Registration with piezoelectric sensors of the normal in vivo activity of the contractile element of the right ventricle]. / Registro con sensores piezoeléctricos de la actividad normal "in vivo" del elemento contráctil del ventrículo derecho.

A new method employed for registration with piezoelectric sensors of the force developed or acceleration of shortening velocity of the contractile element, throughout the right cardiac cycle, is described. The normal activity of the contractile element shows different aspects in both ventricles. SPz curve of the right ventricle is compared with the correspondent SPz curve of the left ventricle. The former curve shows that blood ejection to pulmonary artery is essentially due to developed force or acceleration of shortening velocity of the contractile element, during the isometric contraction phase of the cardiac cycle. Ejection period, with quite constant shortening velocity, seems to complete the blood expulsion. Left ventricular blood flow to systemic circuit is mainly due to early ejection phase, where developed force or acceleration of the shortening velocity of the contractile element appears to be higher, to impulse blood to the aortic artery.

Registro con sensores piezoeléctricos de la actividad normal [quot ]in vivo[quot ] del elemento contráctil del ventrículo derecho. / [Registration with piezoelectric sensors of the normal in vivo activity of the contractile element of the right ventricle]

A new method employed for registration with piezoelectric sensors of the force developed or acceleration of shortening velocity of the contractile element, throughout the right cardiac cycle, is described. The normal activity of the contractile element shows different aspects in both ventricles. SPz curve of the right ventricle is compared with the correspondent SPz curve of the left ventricle. The former curve shows that blood ejection to pulmonary artery is essentially due to developed force or acceleration of shortening velocity of the contractile element, during the isometric contraction phase of the cardiac cycle. Ejection period, with quite constant shortening velocity, seems to complete the blood expulsion. Left ventricular blood flow to systemic circuit is mainly due to early ejection phase, where developed force or acceleration of the shortening velocity of the contractile element appears to be higher, to impulse blood to the aortic artery.