PubMed Health⌕ Search

Biomedical subjects

C Bartolozzi

Publications and source records attributed to C Bartolozzi.

At least 109 records · Page 6Linked to original sources
PubMed1995

Corticospinal tract degeneration in motor neuron disease.

Long-repetition-time spin-echo MR images showed symmetric hyperintensity of the intracerebral corticospinal tracts in two patients with clinical and neurophysiologic diagnosis of primary lateral sclerosis and amyotrophic lateral sclerosis. In both, axial low-flip-angle gradient-echo images of the cervical spine showed hyperintensity of the lateral columns of the cord consistent with antegrade degeneration of the crossed corticospinal tracts.

Adult↗
PubMed1995

MR angiography of spinal vascular malformations.

PURPOSE: To determine the potential and limitations of MR angiography in the evaluation of spinal vascular malformations. METHODS: Eleven consecutive patients with spinal vascular malformations proved with spinal selective arteriography underwent two-dimensional phase-contrast MR angiography. RESULTS: Abnormal vessels within the spinal canal were identified with MR angiography in 10 patients. In 1 patient with a dural arteriovenous fistula no definite vascular abnormality was seen with MR angiography. Correlation of MR angiography with spinal selective arteriography showed that the former allowed identification of the arterial feeder in 3 patients with intramedullary arteriovenous malformations and 2 with perimedullary arteriovenous fistula, whereas the source of intradural draining vein was seen in only 2 of 6 patients with dural arteriovenous fistula. CONCLUSION: MR angiography is a promising complementary tool to MR imaging for detection and characterization of spinal vascular malformations.

Adolescent↗
PubMed1995

[Comparative evaluation of ultrasonography, computerized tomography, angiography and lipiodol CT in defining extent of hepatocarcinoma. A multicenter study].

The authors report the results of a multicentric trial on hepatocellular carcinoma (HCC) patients, whose lesions were confirmed with biopsy or by high (> 400 ng/ml) alpha-fetoprotein levels. The series consisted of 149 patients examined in 8 different centers and submitted to ultrasonography (US), Computed Tomography (CT) before and after contrast agent administration, angiography and Lipiodol CT. According to lesion size and number, the patients were divided with each imaging modality into three groups: a) group 1: unifocal HCC < 5 cm diameter; b) group 2: multifocal HCC with 2-3 nodules and/or tumor mass < 80 ml; c) multifocal HCC with more than 3 nodules (with total tumor mass not exceeding 40% of liver volume) or with total tumor mass > 80 ml. In 77 patients all the examinations were available for comparison. US and CT diagnosed more patients as belonging to group 1 than angiography and Lipiodol CT, while more patients were classified as groups 2 and 3 with angiography and Lipiodol CT, meaning that US and CT may understage some HCC cases (about 15%) because they show a lower number of nodules. This observation was confirmed by the direct comparison between US and Lipiodol CT (in 114 patients), CT and Lipiodol CT (in 103 patients) and angiography and Lipiodol CT (in 116 patients). US and Lipiodol CT were in disagreement in 18 cases, CT and Lipiodol CT in 16 cases and angiography and Lipiodol CT in 13 cases. In most of these cases, Lipiodol CT showed more lesions than the other techniques. The size of the undetected lesions was small, ranging few mm to 2 cm in nearly all cases. To conclude, the results of this multicentric trial show that Lipiodol CT is a fundamental tool to evaluate HCC extent. In contrast, conventional CT appeared not to add any significant piece of information and can therefore be excluded from the diagnostic protocol of HCC.

Angiography↗
PubMed1994

MRI of pleomorphic xanthoastrocytoma: case report.

MRI showed a cortically-based partially cystic and markedly enhancing mass in the uncus of the right temporal lobe in a patient with long standing refractory partial complex seizures. Histopathological examination revealed a pleomorphic xanthoastrocytoma, a rare, usually benign tumour thought to originate from subpial astrocytes.

Adult↗
PubMed1994

Hepatocellular carcinoma: CT and MR features after transcatheter arterial embolization and percutaneous ethanol injection.

PURPOSE: To investigate the reliability of computed tomography (CT) and magnetic resonance (MR) imaging in the evaluation of the response of hepatocellular carcinoma (HCC) to transcatheter arterial embolization (TAE) followed by percutaneous ethanol injection (PEI). MATERIAL AND METHODS: Between January 1991 and November 1992, 20 patients (15 men and five women, aged 53-73 years [mean, 64.6 years]) with 31 HCC lesions underwent CT and MR imaging before and after treatment with combined TAE and PEI. RESULTS: Twenty-seven tumors, which were hypointense on post-treatment T2-weighted images and on gadolinium-enhanced T1-weighted images, were seen to be necrotic at biopsy. In four cases of incomplete necrosis, viable tumor was hyperintense on T2-weighted images and was enhanced after administration of contrast material. CT provided a larger spectrum of imaging features as a result of the presence of both hyperattenuating areas (caused by retention of iodized oil) and hypoattenuating areas (due to ethanol-induced necrosis). CONCLUSION: CT and MR imaging findings proved useful in the evaluation of the response of HCC to combined TAE and PEI.

Aged↗
PubMed1994

Treatment of hepatocellular carcinoma with percutaneous ethanol injection: evaluation with contrast-enhanced MR imaging.

OBJECTIVE: The aim of this study was to investigate the usefulness of unenhanced and enhanced MR imaging in evaluating the response of hepatocellular carcinoma to percutaneous injection of ethanol. SUBJECTS AND METHODS: Thirty-one patients with 40 hepatocellular carcinomas less than 5 cm in diameter were examined with MR imaging before and after percutaneous injection of ethanol. Unenhanced T1- and T2-weighted and contrast-enhanced T1-weighted spin-echo images were obtained. CT and percutaneous biopsy were performed 1 month after the final injection of ethanol and repeated at 6-month intervals to establish the outcome of treatment: complete tumor necrosis was shown in 36 lesions and incomplete tumor necrosis was seen in four lesions. RESULTS: Of the 36 proved necrotic lesions, 31 showed homogeneously low signal intensity on T2-weighted MR images obtained after treatment, owing to coagulative necrosis of the tumor. In the remaining five necrotic lesions, hypointense and hyperintense areas coexisted; the hyperintense areas were caused by liquefactive necrotic material in two cases and by chronic inflammatory tissue along the boundary of the necrotic area in three cases. None of the 36 necrotic lesions showed contrast enhancement on T1-weighted images obtained after IV injection of gadopentetate dimeglumine. In the four lesions with incomplete necrosis, the viable portion of the tumor was identified as a hyperintense area on T2-weighted images and as an enhancing area on contrast-enhanced T1-weighted images. No correlation was found between lesion features on unenhanced T1-weighted images and outcome of therapy. CONCLUSION: Contrast-enhanced T1-weighted MR images allow a reliable evaluation of the effectiveness of treatment and are more accurate than unenhanced MR studies. Contrast-enhanced MR imaging may be considered a valuable alternative to contrast-enhanced CT in the follow-up of hepatocellular carcinomas treated with percutaneous injection of ethanol.

Aged↗
PubMed1994

Friedreich's ataxia: MR findings involving the cervical portion of the spinal cord.

OBJECTIVE: Loss of myelinated fibers and gliosis in the posterior and lateral columns of the spinal cord are histopathologic hallmarks of Friedreich's ataxia. These are accompanied by atrophy of the upper portion of the spinal cord. We performed a study to determine if MR imaging can be used to detect signal changes in the white matter tracts of the cervical spinal cord in these patients. SUBJECTS AND METHODS: The cervical spinal cord was imaged with a 0.5-T MR imaging system in 10 patients with Friedreich's ataxia and in 14 patients with cerebellar ataxias, who served as control subjects. In all of them, the examination protocol included sagittal T1-weighted spin-echo images, sagittal short T1 inversion-recovery images, and axial cardiac-gated long TR spin-echo or ungated low-flip-angle (20 degrees) gradient-recalled-echo images from C2 to C6. The anteroposterior diameter of the spinal cord at the level of C3 on axial images was measured on the display console in patients and control subjects. Two observers who did not know the clinical diagnosis were then asked to evaluate hard copies of the entire image set for each subject for possible intramedullary signal abnormalities. RESULTS: The anteroposterior diameter of the spinal cord was decreased in all but one of the patients with Friedreich's ataxia. Abnormal signal in the posterior or lateral columns of the spinal cord was observed on sagittal and axial images in nine patients with Friedreich's ataxia and in none of the control subjects. CONCLUSION: MR images of the cervical spinal cord in patients with Friedreich's ataxia show thinning and intramedullary signal changes in the cervical portion of the spinal cord, consistent with degeneration of posterior and lateral white matter tracts. These MR findings might be helpful for differential diagnosis in patients with progressive ataxia of uncertain clinical type.

Adult↗
PubMed1994

Long-term follow-up study of adenomatous hyperplasia in liver cirrhosis.

The purpose of this study was to investigate the natural history of adenomatous hyperplasia (AH) in liver cirrhosis, which is suspected of being a precancerous condition of hepatocellular carcinoma (HCC). Sixteen patients with 19 histologically proven AH nodules were followed-up over time with ultrasonographic (US) examinations performed every 3-4 months. The biopsy was repeated whenever the volume of the lesion increased, its US pattern changed, or there was a change in the alpha-fetoprotein values. Thirteen out of 19 AH (68.4%) evolved toward HCC after 8-31 months (mean 14.2 months). Malignant transformation was proved in 7/18 AH within 1 year of its initial detection, in 12/15 AH within 2 years, and in 13/14 AH within 4 years. Six AH remained unchanged in size and US pattern for 9-70 months (mean 29.5 months). Long term follow-up of AH confirms that this lesion is a precursor of HCC.

Adenoma, Liver Cell↗
PubMed1994

[Gadolinium-DTPA combined with a fat suppression technique in studies with magnetic resonance at 0.5 T in soft-tissue neoplasms].

Combination of fat suppression techniques with intravenous paramagnetic contrast administration is usually performed using high-field MR systems. We combined a modified three-point Dixon technique for fat suppression with gadolinium-DTPA administration in the investigation of soft tissue neoplasms at 0.5 T. Nineteen patients with 21 neoplasms (14 primary malignant, 2 metastatic, 5 benign tumors) were examined. Examination protocol included unenhanced SE T1, PD and T2-weighted images. After the intravenous administration of gadolinium-DTPA (0.1 mmol/kg), a modified three-point Dixon technique provided three image sets, i.e., conventional T1-weighted SE images, fat-suppressed T1-weighted images and water-suppressed T1-weighted images. Two observers evaluated the lesions for conspicuity and size in three image groups: unenhanced T1-, PD and T2-weighted images, enhanced conventional T1-weighted images, enhanced T1-weighted images with fat suppression. Ten lesions showed greater conspicuity on enhanced fat-suppressed images than on unenhanced T1-, PD and T2- and enhanced conventional T1-weighted images. In 16 cases lesions were more conspicuous on enhanced water images than on conventional enhanced T1 images. Ten tumors exhibited a larger size (difference exceeding 20%) on enhanced fat-suppressed images. The combination of gadolinium with the modified Dixon technique improves the demonstration of soft tissue neoplasms at 0.5 T and allows lesion size to be measured more accurately.

Adipose Tissue↗
PubMed1994

[Reconstruction of the anterior cruciate ligament with patellar tendon. Comparison between magnetic resonance and computerized tomography].

CT and MR potentials were compared in 30 patients submitted to anterior cruciate ligament reconstruction using the patellar tendon. In each patient the clinical data were correlated with the following radiologic parameters: the course of the tibial and femoral tunnels, their intraarticular outlet sites and their shape, the shape of the intercondylar notch and of the medial wall of the lateral femoral condyle and, finally, the shape of the graft and of the synovia. The intraarticular outlet site of the tibial tunnel was studied on the sagittal or transverse planes. In the former case the distance from the anterior tibial edge was considered, together with its relationship to sagittal tibial depth. The intraarticular outlet site of the femoral tunnel which was studied on sagittal and coronal MR planes was determined at CT by calculating its distance, i.e., the number of scans, from the intercondylar notch and from the posterior edge of the femoral condyle. MRI yielded better results thanks to its multiplanarity, but CT proved superior in defining size and shape of the bone outlets, the presence of bone chips (sometimes responsible for synovial reaction), the shape of the intercondylar notch and of the medial wall of the lateral condyle. As regards graft visualization, both CT and MRI yielded satisfying results in most cases. Nevertheless, MR potentials appeared superior thanks to its capabilities in demonstrating the graft in its full length and in differentiating it from surrounding synovial reaction.

Anterior Cruciate Ligament↗
PubMed1994

[Magnetic resonance angiography at 0.5 Tesla of the renal arteries. Capabilities and limitations of the 2-dimensional phase contrast technique].

To investigate the potentials and limitations of Magnetic Resonance Angiography (MRA) of the renal arteries at mid-field strength, 16 patients with arterial hypertension of suspected renovascular origin were submitted to MRA at 0.5 T with the two-dimensional (2D) phase-contrast technique and to arteriography. MRA yielded diagnostic images in 15 (94%) patients in whom MRA and arteriography identified 38 and 39 renal arteries, respectively. MRA sensitivity and specificity to steno-occlusive alterations of the renal arteries demonstrated by arteriography were 83% and 96%, respectively. These results, although obtained in a small group of patients, indicate that MRA of the renal arteries with a mid-field MR system and the 2D phase-contrast technique can allow the diagnosis of steno-occlusive alterations of the renal arteries. Main MRA limitations were its long acquisition time and some variability in the quality of the MRA images. Nevertheless, the ongoing rapid technical developments in the hardware of MR systems leave room for improving the accuracy of mid-field MRA of the renal arteries and justifies optimism as to its role in the screening of renovascular hypertension.

Adult↗
PubMed1994

[Staging of hepatocellular carcinoma. Comparison of ultrasonography, computerized tomography, magnetic resonance, digital angiography, and computerized tomography with lipiodol].

Accurate staging is necessary in hepatocellular carcinoma (HCC) patients to choose the most appropriate therapeutic approach. In the present study, 50 patients with one or more HCC lesions were prospectively examined with ultrasonography (US), Computed Tomography (CT), Magnetic Resonance Imaging (MRI), digital subtraction angiography (DSA) and CT after intraarterial injection of Lipiodol (Lipiodol CT). The study was aimed at suggesting the most appropriate diagnostic work-up for HCC staging. A hundred and twenty-one HCC lesions were detected in the 50 examined patients by means of the above imaging techniques: namely, 21 patients had single lesions, 15 had two lesions, 4 had three lesions and 10 patients had more than three lesions (range: 4-12). US detected 98/121 lesions (81%), CT 92/121 (76%), MRI 90/121 (74%), DSA 102/121 (84%) and Lipiodol CT 115/121 lesions (95%). The sensitivity of Lipiodol CT was significantly higher than that of all the other imaging techniques (p < 0.05). The detection rate of each technique was correlated with the size of the tumors, which were divided into three groups: lesions < or = 1 cm (no. 28), lesions ranging 1.1 to 3 cm (no. 43) and lesions > 3 cm (no. 50). In the lesions < or = 1 cm, detection rates ranged 29-93%; in this group a statistically significant difference (p < 0.01) was observed between Lipiodol CT and all the other imaging modalities. In the lesions 1.1-3 cm, detection rates ranged 77-93%; in this group a statistically significant difference (p < 0.05) was observed between Lipiodol CT and MRI. In the lesions > 3 cm, sensitivity was very high for all imaging modalities--i.e., 94% or higher; in this group no statistically significant difference was observed among the various imaging modalities. Combined US and CT detected 104/121 lesions (86%), US and MRI 101/121 (83%) and CT and MRI 98/121 (81%). The combination of US, CT and MRI allowed the detection of 107/121 lesions (88%), which markedly improved the results of US alone (the statistical index was just above the one usually considered to be significant). In conclusion, our data suggest the following staging work-up for HCC: (a) US as the first step diagnostic tool; (b) CT and possibly MRI, in the cases with a single lesion at US and in the patients eligible for surgery; (c) Lipiodol CT in the cases which CT and MRI confirmed to be single lesions.

Adult↗
PubMed1994

Lipiodol-CT in the detection of tumor persistence in hepatocellular carcinoma treated with percutaneous ethanol injection.

Our purpose was to investigate the usefulness of Lipiodol-CT for detection of residual viable neoplastic tissue in hepatocellular carcinoma (HCC) lesions treated by means of percutaneous ethanol injection (PEI). An emulsion of 5 to 20 ml iodized oil and 50 to 70 mg doxorubicin hydrochloride was intraarterially injected in 18 patients with 25 HCC lesions treated by means of PEI one to 24 months before. At CT performed 3 to 5 weeks after injection, retention of Lipiodol was observed in 9 of 13 tumors that still contained viable neoplastic tissue and in 2 of 12 tumors proven to have undergone complete necrosis after PEI. The sensitivity and specificity of Lipiodol-CT were 69.2% and 83.3%, respectively. Thus, Lipiodol-CT seems to have limited diagnostic value after PEI, probably as a consequence of the alcohol-induced vascular damage, accounting for both false-negative and false-positive results.

Aged↗
PubMed1994

Percutaneous ethanol injection therapy of adenomatous hyperplastic nodules in cirrhotic liver disease.

Adenomatous hyperplastic nodules (AHNs) in cirrhotic liver are considered a precancerous condition which may lead to hepatocellular carcinoma (HCC). In this study, we treated a total of 23 AHNs in 15 patients with percutaneous ethanol injection (PEI). The treatment included 6 to 8 PEIs, performed on an out-patient basis under sonographic guidance. A 22 G (0.7 mm) spinal needle was used. The total amount of alcohol delivered into each lesion was 8 to 25 ml (mean 14.9 ml). At the end of treatment, complete necrosis of the nodule was proved in all cases by multiple fine-needle biopsies and confirmed by CT and MR findings. During follow-up (9-41 months, mean 24 months) no recurrences were demonstrated. However, HCC occurred elsewhere in the liver of 4 patients and additional AHNs were detected in 2 patients. Thus, PEI proved able to cause complete ablation of AHNs, presumably preventing their malignant transformation. However, patients with AHN remain at high risk for developing HCC.

Aged↗
PubMed1993

Management of adenomatous hyperplastic nodules in the cirrhotic liver: US follow-up or percutaneous alcohol ablation?

In order to investigate the most appropriate management of adenomatous hyperplastic nodules in cirrhosis (AHNs), retrospective and prospective studies were undertaken. The retrospective study included 11 AHNs detected in nine patients, who were followed with ultrasonography (US) and fine-needle biopsy (FNB); seven of these lesions evolved into hepatocellular carcinoma (HCC) after a mean follow-up period of 11.4 months. The prospective study involved 19 AHNs (in 12 patients) that were submitted to percutaneous ethanol injection (PEI); all lesions underwent necrosis at the dynamic computed tomographic (CT) examination and at multiple FNBs performed 1 month after the end of treatment. In four patients studied with magnetic resonance (MR), all treated lesions were markedly hypointense in the T2-weighted images. No complications occurred after a total number of 114 alcohol injections. No local recurrences were observed after a mean follow-up period of 16.9 months. PEI should therefore be considered mandatory in the management of AHNs.

Aged↗
PubMed1993

Effectiveness of the Short TI Inversion Recovery (STIR) sequence in MR imaging of intramedullary spinal lesions.

A Short TI Inversion Recovery (STIR) sequence with spin-echo data collection was compared to a conventional cardiac gated long TR spin-echo (SE) sequence for detecting intramedullary signal abnormalities. The cervical (n = 48), cervico-thoracic (n = 1), and thoraco-lumbar (n = 18) spinal cord was imaged in a sagittal plane with a 0.5 T (n = 61) or 1.5 T (n = 6) MRI unit in 67 patients with clinical evidence of myelopathy of different etiologies (e.g., multiple sclerosis, trauma, herniated intervertebral disk, spondylosis, etc.). In all patients, ungated double or quadruple echo STIR images (TR 1000-1400 msec, TI 100 msec, TE 30-60 or 30-60-90-120 msec) were compared with cardiac gated long TR (1400-2100 msec), double echo (30-100, 50-100, or 50-150 msec) SE images with first order flow compensation for the second echo. Although STIR images appeared "noisier" than long TR SE images, they showed fewer ghost artifacts. In 55 patients, single or multiple, focal or diffuse, hyperintense areas within the spinal cord were observed on both long TR SE and (magnitude reconstructed) STIR images. Lesion conspicuity was better on the STIR images in 25 patients, better on the SE images in 14 patients, and equal in 16. STIR sequence provides a valuable alternative to gated long TR SE sequence for the MRI investigation of intramedullary spinal lesions.

Adolescent↗
PubMed1993

Acute spinal trauma: prognostic value of MRI appearances at 0.5 T.

Thirty-two patients with post-traumatic myelopathy were examined with a 0.5 T MRI system within 4 days of injury and the MRI findings analysed with respect to the immediate and residual functional deficit and (in 20 patients) the MRI appearances of the spinal cord in the chronic phase. In the acute phase a normal spinal cord was associated with only slight clinical deficit in four patients. Signal abnormalities in the spinal cord at the site of trauma were identified on T2-weighted spin-echo or T2*-weighted gradient-recalled echo images in 28 patients. The 12 most functionally impaired patients showed focal low signal suggestive of intramedullary haemorrhage: the other 16 had homogeneous high signal consistent with diffuse oedema. Swelling of the spinal cord and mild persistent cord compression following reduction were noted in 17 and 26 patients respectively. All patients were treated conservatively other than undergoing surgical decompression. Four died of complications. No patient with low signal in the spinal cord on initial MRI showed significant clinical improvement. Five whose spinal cord was hyperintense remained unchanged, whereas nine made a significant recovery, as did all patients with normal-appearing spinal cords. Cord compression on the initial examination was not relevant to clinical outcome. Intramedullary scars were identified at follow-up in 18 patients and were more extensive in those with haemorrhagic acute lesions. Haemorrhagic contusion of the spinal cord can be demonstrated in the acute phase with midfield MRI and is a valuable predictor of the functional outcome in patients with traumatic myelopathy.

Acute Disease↗