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Twenty-two patients who presented with laterocervical retromandibular enlargement were examined with both US and MR imaging to assess the intrinsic/extrinsic relationship of the mass to the parotid gland, the involvement of the facial nerve and adjacent structures, as well as the nature of the mass. Both US and MR imaging proved to be poorly specific in the characterization of the inflammatory lesions. Within the mass, both methods revealed high sensitivity (100%) in identifying the lesions, even very small ones. MR imaging allowed the lesion to be accurately located, the facial nerve to be identified, and its possible infiltration to be evaluated, with higher reliability than US, thanks to its higher contrast resolution and to its multiplanarity. Neither US nor MR imaging allowed the benign/malignant nature of the lesion to be assessed. On the basis of their experience, the authors suggest the use of T2-weighted MR sequences, with long TR and TE, to differentiate pleomorphic adenomas from other histotypes, after US assessment of the solid nature of parotid masses.

Physical and instrumental examination of the patients with an "aching shoulder" is often difficult and a positive out-come of surgical treatment may be impaired by the late diagnosis of long-standing rotator cuff lesions causing tendon adhesions and muscle atrophy. The authors report the results obtained in 25 selected patients with an aching shoulder examined with arthrography, real-time ultrasound (US) with a 5 MHz linear probe, and high-field (1.5 T) Magnetic Resonance (MR) imaging. Arthrography was able to demonstrate a cuff tear in 14/25 cases; US detected signs of tear in 14/25 (1 false negative); MR imaging showed a cuff lesion in 16/25 patients, and in one case allowed a partial cuff tear to be demonstrated, which had not been visualized with arthrography. MR imaging could also demonstrate other signs of periarticular pathologies (tendinitis, longhead of biceps inflammation, and bursitis) that may represent the early stages of the inflammatory-degenerative process underlying most of cuff lesions. The high diagnostic accuracy of US (95%) is stressed in the detection of cuff tears, in patients with an aching shoulder; as for questionable cases at US, MR imaging is indicated as a valid alternative to arthrography, which is more invasive and less accepted by the patients.

The authors report their experience of knee articular pathologies studied with MR imaging. Forty patients (36 with and 4 without articular trauma) were examined with both MR imaging and arthroscopy. Arthroscopic findings were correlated with MR results in order to evaluate the accuracy of the latter in detecting meniscal tears. MR images were obtained with a 1.5 T unit and a transmit-receiver surface coil. Spin-echo sequences and, occasionally, fast-scan sequences were used both in the coronal and in the sagittal planes. High resolution MR imaging clearly depicted knee anatomy. As far as meniscal lesions were concerned, the authors employed a grading system to classify intrameniscal signals, as proposed by Lotysch. The preliminary results are encouraging and suggest the use of MR imaging as the first imaging modality for use in knee pathology before arthroscopy is performed.

The authors report the observations derived from CT evaluation of 19 cases of lumbosacral conjoined nerve roots; 11 of these have been confirmed by lumbar myelography and/or at surgery. They conclude that CT without intrathecal metrizamide allows the recognition in most cases of the presence of conjoined nerve roots and to differentiate them from a herniated disk fragment; this is especially useful to avoid surgical damage of anomalous roots.

Human skin fibroblasts, isolated in vitro, from donors carrying the Mediterranean variant of glucose-6-phosphate dehydrogenase, exhibit a sharp decrease of hexose monophosphate shunt and NADPH/NADP+ ratio when compared to the fibroblasts from normal donors. This behavior is coupled to an increase of the resistance to cell death and growth inhibition induced by benz(a)pyrene, whose activation proceeds through the NADPH-dependent arene oxide formation. No differences were observed in the toxic effects of methylnitrosourea, a carcinogen that does not need metabolic activation, on normal and variant fibroblasts.