Color Doppler measurement of blood flow in the inferior thyroid artery in patients with autoimmune thyroid diseases.

PURPOSE: The aim of the study is to find out whether the measurement of peak systolic velocity in the inferior thyroid artery (ITA) is a valuable parameter to differentiate autoimmune thyroid diseases (hyper-, normo- or hypofunctional) and to evaluate the efficacy of medical treatment. MATERIAL AND METHODS: The ITA of 31 patients (eight with Graves' disease, 23 with subclinical hypothyroidism) was examined with color Doppler and pulsed Doppler. The final diagnosis was obtained by cytology and by hormonal and antibodies assays. The patients were monitorized by ultrasound for a period of 8 months. RESULTS: In all the patients with Graves' disease the peak systolic velocity was always over 150 cm/s, while in other autoimmune thyroiditis the peak systolic velocity was within the normal range, and never exceeding 65 cm/s. In the first group, the measurement taken in the ITA showed also the efficacy of the pharmacological treatment earlier and more reliably than the color Doppler pattern obtained in the parenchyma. CONCLUSIONS: The color Doppler measurement of the ITA seems to be a promising technique with low-cost and easy approach. In our experience, the color Doppler of the ITA could have a clinical role in the differential diagnosis of diffuse thyroid diseases and in the follow-up of the Graves' disease during medical treatment.

Plain film, CT and MRI sensibility in the evaluation of intraorbital foreign bodies in an in vitro model of the orbit and in pig eyes.

Detection and characterization of intraorbital foreign bodies (IFB) is fundamental in acute trauma setting, preventing inflammatory sequelae or complications related to IFB movements when a MRI study is planned. Papers concerning plain film and CT sensibility in IFB detection show controversial results. For this reason we investigated plain film, CT and MRI sensibility in the evaluation of IFB. For an in vitro model, specimens of dry and fresh wood, glass, iron, plastic and graphite were immersed in animal lard and in a 0.9% sodium chloride plus 3.5 g/dl human serum albumin solution. Specimens of different size and nature where also implanted into enucleated pig eyes. Air bubbles were introduced also. Plain film, CT and MRI investigation were performed. Plain films underestimated intraocular IFB as plastic, fresh or dry wooden IFB were not demonstrated. The CT study was always able to depict and differentiate IFB according to the attenuation values. Severe artefacts prevented demonstration of iron, glass and graphite IFB on MRI, whereas plastic or wooden IFB were always detected. Despite radiographs have been suggested as a prerequisite for MR imaging, because our results showed plain film to underestimate radiolucent IFB, we suggest CT as the modality of choice when IFB has to be ruled out.

[Changes in the blood-labyrinth barrier. Assessments by magnetic resonance]. / Alterazioni della barriera emato-labirintica. Valutazioni mediante Risonanza Magnetica.

PURPOSE: Recent progress in magnetic resonance imaging (MRI), with contrast-enhanced and steady-state sequences, allows fine depiction of labyrinth abnormalities related to neoplastic, inflammatory, ischemic, degenerative or traumatic disorders. We examined 488 patients with sensorineural hearing loss, vertigo or dizziness, but normal CT findings, to evaluate MR capabilities in showing labyrinth conditions. MATERIAL AND METHODS: January 1994 to May 1998, four hundred and eighty-eight patients with labyrinthine symptoms were submitted to CT. Sixty-eight of them, with normal CT findings, were also examined with MRI, which was performed using quadrature head or surface coils and a single dose (0.1 mmol/kg) Gd-DTPA administration. Conventional T1 and T2 high resolution SE images were acquired. The labyrinth was studied of 52 patients with normal CT findings and no abnormalities in the cerebello-pontine angle or internal auditory canal. RESULTS: Fourteen of 52 patients (27%) exhibited labyrinth enhancement from tumor (5%), hemorrhage (3%), infection (15%), surgical (2%) or radiosurgical (2%) procedures. GRASS sequences allowed differentiation of mass lesions (e.g., tumors, clots) from other conditions. CONCLUSION: Generally the labyrinth exhibits no contrast enhancement even after a triple Gd-DTPA dose. In inflammatory conditions, enhancement is not always diffuse, as expected, but may be focal. Spontaneous hemorrhages can account for labyrinth enhancement. In neoplastic conditions, enhancement may persist for as many as 6 months, and a mass effect against labyrinthine fluids may appear on GRASS images. Although there are no reports on labyrinthine degeneration after radiation therapy, one of our patients submitted to irradiation 7 years previously, had focal bilateral cochlear enhancement, which suggested a correlation with previous treatment.

MRI findings in lingual venous malformations.

OBJECTIVES: To describe the plain and enhanced MRI findings of lingual venous malformations and to discuss the importance of contrast medium in the differential diagnosis of high intensity lesions of the tongue on T(2) weighted images. METHODS: The clinical records and MR images of eight patients affected by a lingual venous malformation were retrospectively reviewed. Patients presented with a palpable submucosal bluish-red soft mass in the tongue. MRI examinations were performed on a 0.5 T superconducting unit. Plain and enhanced SE (spin echo) T(1) weighted and FSE (fast spin echo) T(2) weighted images were acquired in axial, sagittal and coronal planes. Axial SPGR (spoiled gradient recalled echo) T(1) weighted images were also obtained before and after intravenous (i.v.) injection of paramagnetic contrast medium. RESULTS: Five of eight venous malformations were located at the tip of the tongue. The other three involved the whole tongue and had an extralingual extent; two extended into the submandibular space and one into the glossoepiglottic valleculae. The largest diameter ranged from 2.5 cm to 8 cm. All lingual venous malformations presented as lobulated masses that were slightly hyperintense or isointense on T(1) weighted images and highly hyperintense on T(2) weighted images with respect to normal tongue and/or surrounding muscles. They showed a slow and homogeneous filling following iv injection of contrast medium. Millimetre-sized hypointense foci and linear hypointense strands were sometimes noticed, which were owing to phleboliths, flow void or septation. CONCLUSION: Knowledge of MRI findings of lingual venous malformations is useful for differential diagnosis with other high intensity lingual lesions on T(2) weighted images. This discrimination is achievable using iv paramagnetic contrast medium.

Analysis of radioactive pollution in the Gulf of Palermo.

PURPOSE: Sea water represents more than three quarters of the whole world. The radioactive fall out caused by nuclear experiments, radioactive drosses from nuclear power plants and other pollution sources, are able to contaminate the world ecosystems, and especially the sea water. The aim of this work is the evaluation of a possible radioactive pollution in the Gulf of Palermo. MATERIAL AND METHODS: The Gulf of Palermo was divided into 5 homogeneous hydrological parts, in which fish and water were collected. The dosage of 131I e del 137Cs was mainly assessed because they have a long half-life and their presence in the water can be due to nuclear accidents but also to a wrong removal of the waste materials of nuclear medicine procedures; the other radioisotopes assessed (144Ce, 106Rh, 140La) are due only to nuclear fall-out. Gamma spectrometry technique was used for the evaluation of the radioisotopes' concentration after an adequate treatment of the samples. RESULTS AND CONCLUSIONS: The concentration of the examined radionuclides was below the instrumental capability apart from the 137Cs, whose dose was increased, and can be due to nuclear accidents and explosions. The radionuclide levels detected do not determine a higher risk than normal for the population's health even regard the eatablity of ittical species.