Primary leiomyosarcoma of the oral tongue: magnetic resonance and ultrasonography findings with histopathologic correlation.

Leiomyosarcoma is a malignant smooth muscle tumor that frequently occurs in the gastrointestinal tract and female genital tract. It is aggressive and tends to recur and metastasize. Clinical behavior is unpredictable, mostly influenced by a proper surgical approach. Oral leiomyosarcoma, in particular of the tongue, is extremely rare and poorly documented in the radiology literature. Diagnostic assessment of oral leiomyosarcoma is often challenging, mostly founded on its peculiar immunohistological features. However, imaging evaluation is essential in staging and for preoperative planning. We illustrate the case of a 52-year-old woman with 2-months history of a painless growing mass on the left hemitongue, with magnetic resonance and ultrasonographic features correlated to histopathologic examination.

Impaired quantitative cerebral blood flow in scleroderma patients.

Systemic Sclerosis (SSc) is a multisystem disease characterised by proliferation of vascular tissue, obliterative microvascular lesions and diffuse organ fibrosis. Despite widespread vascular disease, Central Nervous System complaints are only infrequently reported and it is uncertain whether they merely derive from systemic complications or whether they may be also caused by a primary vascular process within the brain. Regional cerebral blood flow (rCBF) was quantitatively measured by the 133Xenon clearance technique in twenty-seven consecutive SSc patients without relevant systemic complications and with different severity of vascular involvement, as staged by nailfold capillary videomicroscopy (NCV). Absolute, percent, and asymmetry rCBF values were compared (z-statistics) with age- and sex-matched healthy controls. Cerebral MRI and Mini-Mental State Examination (MMSE) were also performed. Doppler sonography of neck vessels and Transcranial Doppler sonography (TCD) were performed in patients presenting rCBF reduction. Cerebral hypoperfusion was found in the 52% of patients, i.e.: in 33% of patients with the 'early' NCV pattern, in 56% of patients with the 'active' pattern, and in 67% of patients with the 'late' NCV pattern. Thirty percent were the MRIs showing focal and/or diffuse signal abnormalities in the white matter of both hemispheres with the highest rate (44%) in the 'late' NCV pattern. MMSE disclosed mild dementia in one patient in the 'late' NCV group and some mistakes in 6 more patients, in the 'active' or 'late' NCV groups, whereas TCD failed to find significant stenosis of Willis' arteries. Cerebral hypoperfusion is shown for the first time in a substantial part of SSc patients without either neurological symptoms or relevant systemic complications. It is suggested that the rCBF reduction might be related to the systemic scleroderma microangiopathy although, probably due to the paucity of connective tissue in cerebral vessels, the vast majority of patients remains in a subclinical phase.

[The role of T2*-weighted gradient-echo magnetic resonance sequences in the study of suspected dorsal-lumbosacral vertebral metastases]. / Ruolo delle sequenze di Risonanza Magnetica gradient-echo T2*-pesate nello studio delle sospette metastasi vertebrali dorso-lombosacrali.

INTRODUCTION: Magnetic resonance (MR) imaging showed high reliability in detecting spine metastases with spin-echo (SE) sequences, T1-weighted sequences being generally more sensitive than T/-weighted ones. We investigated the value of T2*-weighted gradient-echo (GE) sequences in studying spine metastases. MATERIALS AND METHODS: Twenty patients with established diagnosis of primary carcinoma and clinically suspected thoracic and/or lumbosacral spine metastases underwent .5-T MR imaging and 99mTc-HDP bone scan. The disagreement of GET2*- versus SET2-weighted images as well as versus bone scan and the disagreement of total MR results versus bone scan results were evaluated by McNemar test. The agreement of GET2*- versus SET1-weighted images was evaluated by Cohen's kappa. RESULTS: Of a total of 111 MR signal abnormalities consistent with metastasis, 109 (98.2%) were T2*-hyperintense, whereas only 50 (45.1%) were T2-hyperintense (p < .0001) and 51 (45.9%) were detected with bone scan (p < .0001). Of a total of 121 MR and/or bone scan findings consistent with metastasis, 111 (91.7%) were MR positive, with high disagreement with 61 (50.4%) positive at bone scan (p < .00001). T2*-hyperintensity associated with T1-hypointensity (with or without T2-hyperintensity) was the most frequent pattern (104/111), 93.7%). CONCLUSIONS: T2*-weighted GE sequences seem to be more effective than T2-weighted SE sequences and as effective as T1-weighted SE sequences. MR imaging confirms its ability in detecting abnormalities consistent with spine metastases.

Helical versus conventional CT in detecting meniscal injuries.

PURPOSE: We compared volumetric helical and conventional CT in the study of meniscal injuries. MATERIAL AND METHODS: Thirty-three patients with suspected meniscal tear underwent helical and conventional CT. Common parameters were 512 x 512 matrix, 14-15 cm FOV, 120 kV and 175 mA; helical CT was performed with 2 mm beam thickness, 1.5 mm/s table feed, 1 mm reconstruction index and conventional CT with 2 s scan time, 1 mm slice thickness and 1 mm table feed. All scans were photographed with a Laser printer using the same window (180/100). All patients also underwent sagittal and coronal T2* GE MRI at .5-T; slice thickness was 5 mm and interslice gap 1 mm. Nonparametric scales were used to study the menisci, as follows: for CT we had A = no visible injury; B = diffuse hypodensity (degenerative condition); C = questionable meniscal tear; D = unquestionable meniscal tear. For MRI, we had A = no visible injury; B = grade 1 or 2 injury; C = grade 3 injury; D = grade 4 injury. We used the 1-4 MR grading by Lotysch et al. and by Crues et al. MRI was used as the gold standard. The agreement between helical CT, conventional CT and MRI was calculated with kappa statistics. RESULTS: Helical and conventional CT found 23 and 15 patterns A, 6 and 10 B, 3 and 1 C and 1 and 7 D, respectively. MRI found 15 A, 8 B, 3 C and 7 D. There was no agreement between helical CT and MRI and between helical CT and conventional CT because of the meniscal tears underestimated by the former. Agreement was very high between conventional CT and MRI (p < .001). DISCUSSION AND CONCLUSIONS: The main result of our experience is that helical CT appears less sensitive than conventional CT in detecting meniscal tears. The helical CT section profile (more roundish than that of conventional CT) and the lower radiation dose used by helical CT (with increased quantum noise) may have played a key role in its underestimation of meniscal tears.

[Magnetic resonance mammography in suspected tumor recurrences]. / La mammografia con Risonanza Magnetica nelle sospette recidive tumorali.

Twenty patients with clinically suspected breast cancer recurrence underwent MRI before and after paramagnetic contrast agent administration (MR mammography, MRM), after negative (4/20), questionable (11/20) or positive (5/20) X-ray mammography (XM). Spin-echo T1-weighted images before and after the i.v. administration of Gd-DTPA (0.15 mmol/kg) were acquired at 1, 3, 5, 7 and 10 minutes. Tissue behavior was studied directly on the images (qualitative analysis) and with dynamic curves of the signal-to-noise ratio and of enhancement rate (quantitative analysis). The histologic examination was performed in all cases--18 of them by surgical excision and in two by needle biopsy only. Seven of seven recurrences exhibited early (at 1 and 3 minutes) and focal qualitative enhancement, exceeding 100% at the quantitative analysis. Twelve of thirteen non-recurrences exhibited no significant qualitative enhancement, less than 40% at the quantitative analysis, while the extant lesion exhibited multifocal delayed (at 5-10 minutes) qualitative enhancement, about 60% at the quantitative analysis, and slight bilateral diffuse enhancement (proliferative dysplasia). MRM had 100% sensitivity, 92.3% specificity, 87.5% positive predictive value and 100% negative predictive value. XM had 100%, 30.8%, 43.7% and 100%, respectively (if we consider as positive all the questionable XM cases). To conclude, MRM is confirmed as a useful imaging technique in suspected breast cancer recurrences, especially after questionable XM exams.

A device enabling single unit recordings during head movements in cats.

An inexpensive light weight head restraint device enabling horizontal rotational head movements is described. The restrainer provides sufficient stability to allow prolonged single unit recording and is compatible with conventional recording techniques.