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T Scarabino

Publications and source records attributed to T Scarabino.

36 records · Page 2Linked to original sources

Surgical treatment of anterior callosal tumors.

OBJECTIVE: Thirteen patients with neoplasm of anterior corpus callosum have undergone our observation during the last two years. METHODS: For the diagnosis, all the patients underwent TC, NMR and stereotactic biopsy. In 6 cases with glioblastomas, a radiation treatment was adopted. The other 7 patients underwent total surgical treatment in 5 cases, and partial in 2 cases, as documented by postoperative contrast-enhanced CT scanning. Histologically, there were: 3 glioblastomas, 1 grade III astrocytoma, 1 neuroblastoma (PNET), 2 pilocytic astrocytomas. RESULTS: Neuropsychological tests carried out on the 5 patients still living showed persistent disturbances of verbal memory in all five and disturbances of verbal phonological fluency in 3 cases. No patient presented apraxia, dysgraphia and dyslexia. CONCLUSIONS: Thus, no severe neuropsychological deficits developed after surgical treatment of anterior callosal tumors.

Adolescent↗

[Choledocholithiasis: semeiotic and diagnostic accuracy of cholangiography with magnetic resonance].

The authors report their experience in the optimization of the diagnostic accuracy of Magnetic Resonance Cholangiography (MRC) to detect choledochal stones; pre- and post-MIP post-processing images were compared. Thirty patients with dilated biliary ducts (mean age: 55.6 years) were examined with MRC; two of them had stones in the intrahepatic biliary ducts. The gold standard and the inclusion criterion was ERCP. MRC was carried out with a 1.5 T superconductive magnet (Signa) with T2-weighted FAST SE sequences (TR/TE; 10000/256, matrix: 256 x 128, slice thickness: 3 mm, TA: 6 min 28 s). Coronal MR images were blindly studied before and after MIP post-processing; Friedman's test was used for statistical analysis (p < .05). ERCP showed 92 cases of choledocholithiasis, with the stones ranging .2 to 3.4 cm; MRC before MIP post-processing had 97.1% diagnostic accuracy, 97.8% sensitivity and 95.8% specificity. These values are significantly different from those obtained after MIP (91.4%, 86.9% and 95.8% respectively). In our experience, pre- and post-MIP post-processing MRC can be considered a reliable and accurate noninvasive technique to detect choledochal stones.

Cholangiopancreatography, Endoscopic Retrograde↗

[Whole-body magnetic resonance angiography using a contrast medium. Technical optimization].

INTRODUCTION: We tried to optimize the technique of contrast enhanced MR Angiography (MRA) in the study of the main body arteries. MATERIALS AND METHODS: Fifty volunteers were examined with contrast enhanced MRA with a superconductive magnet at 1.5 T (Signa GE) and 3D SPGR sequences acquired with the following parameters: TR 8.2 +/- 1.3 ms, TE 1.8 +/- 7 ms, FA 60 degrees, MA 128 X 256; the images were acquired on the sagittal or coronal planes. The contrast agent (Gd-DTPA) was injected with MedRad Spectris system, with the bolus technique and the following standard parameters: velocity 1.5 mL/s and single dose; circulation time was optimized with 2D SPGR for each vessel (pretest). The carotid and pulmonary arteries, the thoracic-abdominal aorta and the iliac arteries were studied. The reader used a multiple choice card to evaluate image quality, signal-to-noise ratio (SNR) and circulation time. RESULTS: Circulation time was 10.2 s in the carotid arteries, 8.1 s in the pulmonary arteries, 10.3 s in the thoracic aorta, 12.2 s in the abdominal aorta and 13.8 s in the iliac arteries. The signal was 181.8 vs the noise 3.1 in the carotid arteries, 256.8 vs 23.2 in the thoracic aorta, 518.4 vs 23.5 in the pulmonary arteries, 258.8 vs 24.5 in the abdominal aorta and finally 262.7 vs 25.4 in the iliac arteries. CONCLUSIONS: Our experience suggests that contrast enhanced MRA is a good technique to study body arteries.

Adult↗

[Magnetic resonance angiography of the vessels of the neck: the optimization of a dynamic technic during the rapid infusion of a paramagnetic contrast medium].

INTRODUCTION: A new noninvasive technique, dynamic Magnetic Resonance Angiography (MRA) during rapid infusion of paramagnetic contrast medium, has been recently developed for the study of neck vessels. This study was carried out to optimize technical parameters. MATERIALS AND METHODS: Twenty healthy volunteers (10 men and 10 women; age range: 25 to 50 years) were examined with a 1.5 T MR unit equipped with fast imaging software and a dedicated coil. Dynamic MRA was performed using fast spoiled gradient recalled (fast SPGR) sequences acquired on the coronal plane 13 s after contrast medium injection. Imaging parameters were: Echo Time (TE): 1 ms, Repetition Time (TR): 8 ms, flip angle: 60 degrees, matrix 256 x 128, number of excitations: 1, field of view: 18 x 13 cm, number of partitions per slab: 28, slice thickness: 1 mm, acquisition time: 32 s. A dose of .2 mmol/kg of paramagnetic contrast medium was administered with an MR compatible automatic injector, at a speed rate of 1.5 ml/s. Angiographic images were postprocessed with the maximum intensity projection (MIP) and targeted MIP algorithms. RESULTS: Using the above parameters and rapid contrast medium injection, the carotid arteries on the coronal plane (including the vessels from the proximal aspect of the common carotid arteries to the intracranial tract of the internal carotid arteries) in 18 cases. In the other two cases the tortuosity and the position of the carotid arteries on two different planes, prevented their complete visualization. The vertebral arteries were completely demonstrated in 50% of the investigated population. Partial or total overlapping of jugular veins did not affect the recognition of the carotid vessels in 10 cases, also with targeted MIP postprocessing. DISCUSSION: The vascular semiology of dynamic gadolinium enhanced MRA seems to be closer to that of conventional angiography than of conventional MRA, likely due to the same modality of vessel depiction, based on contrast medium administration. Flow artifacts, the major pitfall of conventional MRA causing signal void and overestimation of stenosis grade, are not frequent in dynamic MRA. CONCLUSIONS: Gadolinium enhanced dynamic MRA ensures panoramic and high resolution angiographic-like depiction of the neck vessels, providing rapid and excellent definition of vascular morphology. Thus dynamic MRA appears to be a substantial alternative to conventional MRA and conventional angiography.

Adult↗

[The reduction of ferromagnetic artifacts by using a fast-spin-echo sequence in the postoperative assessment of degenerative diseases of the cervical spine].

This study was aimed at investigating if fast spin echo (FSE) pulse sequences can increase the diagnostic capabilities of MRI in the patients with degenerative disease of the postoperative cervical spine, considering their lower magnetic susceptibility than that of conventional spin echo (SE) sequences. The patient population consisted of 15 patients submitted to diskectomy after Cloward and Caspar. MR images were acquired with a 1.5-T unit (Signa, General Electric) with T2-weighted FSE versus conventional T1- and T2-weighted SE images. Thanks to fewer metallic artifacts, FSE images of the postoperative cervical spine yielded more pieces of information than conventional SE sequences in demonstrating the spine and its content. The best results were obtained in the patients with canal stenosis (8 patients) and myelomalacia (2 patients). In addition, the myelographic effect, another major semiologic feature of the FSE technique, provided further diagnostic information in these patients. Moreover, shorter examination times resulted in better patients tolerance, especially in those with recent surgery. Finally, reducing motion, blood flow or CSF flow artifacts definitely improved FSE image quality.

Aged↗

[Magnetic resonance myelography with a fast-spin-echo sequence].

A major application of Magnetic Resonance Imaging (MRI) consists in the "myelographic effect", characterized by high signal intensity of the CSF, which permits to visualize spinal subarachnoid spaces and nerve root sheaths. Such new ultrafast pulse sequences as fast spin echo (FSE) further enhance CSF high signal intensity. In addition, suppressing background with the fat suppression technique and with maximum intensity projection (MIP), a particular algorithm already used in MR angiography, FSE sequences yield 3D myelography-like images. Our study was aimed at assessing the clinical role and the reliability of this technique. Our preliminary experience is based on 21 patients with pain in the lower back and legs and on 5 healthy volunteers; all the myelography-like images were obtained with a 1.5-T MR system (Signa, General Electric). The parameters for FSE myelography-like images included: TR = 6000, TE = 200, ETL = 32, thickness = 3 mm, matrix = 256 x 224, Nex = 4, FOV = 20 cm, fat presaturation, no phase wrap, acquisition time = 2 min 58 s. MR myelography sequences were acquired after a standard FSE T1/T2-weighted exam. MR-myelography results confirmed the diagnosis of disk herniation made on conventional T1/T2-weighted images, especially in thecal sac compression and/or amputation of nerve root sheaths. MR myelography appeared to be especially useful in migrated disk herniation or in abnormal origin of nerve roots. Moreover, it allowed full and panoramic visualization of the subarachnoid spaces and excellent definition of the thecal sac, nerve roots and nerve root sheaths. In one patient only movement artifacts affected image quality. To conclude, even though it fails to yield any functional information, MR myelography appears to be an easy, rapid and noninvasive support to conventional MRI of the lumbar spine, to replace conventional myelography.

Female↗

[Fast spin echo imaging of vertebral metastasis: comparison of fat suppression techniques (FSE-CHESS, STIR-FSE)].

PURPOSES: To investigate the capabilities of fast spin echo (FSE) sequences in diagnosing spinal metastases and to compare two fat-suppression techniques: CHESS (chemical shift selective saturation) and STIR (short T1 inversion recovery). Fat suppression is recommended with FSE sequences because on them, different from conventional spin echo (SE) sequences, fat has high signal intensity in both T1 and T2 weighting, masking such high-signal bone lesions as metastases. METHODS: Ninety metastatic lesions in 32 patients were studied with T1-weighted SE and T2-weighted FSE sequences with and without fat suppression (FSE-CHESS and STIR-FSE). Quantitative analyses (metastasis size, signal intensity, margins and conspicuity) and qualitative analyses (artifacts and fat saturation homogeneity) were carried out of both fat-suppression sequences. Signal-to-noise (S/N) and contrast-to-noise (C/N) ratios were calculated in 20 metastatic lesions. The results were analyzed with the chi 2 method and the paired t-test. RESULTS: Both fat-suppression FSE sequences were more sensitive to focal lesions (100%) than T1-weighted SE sequences (96.6%). Lesion signal was higher than that of surrounding bone in 95.5% of fat-suppressed images, which facilitated the recognition of spinal metastases. On the contrary, conspicuity was higher (73.3%) and the margins more definite (68.8%) on T1-weighted SE than on T2-weighted FSE sequences. Fat suppression was more apparent on STIR-FSE than on FSE-CHESS sequences, even with no significant difference in C/N ratio. CONCLUSION: Both STIR-FSE and FSE-CHESS sequences are rapid and useful techniques to obtain fat saturation in FSE images. CHESS saturation is selective on fat signal, while STIR suppresses the signal of all the substances with the same short T1 as fat.

Adipose Tissue↗

[Imaging with magnetic resonance imaging of the operated cervical spine].

The Authors report their personal experience with postoperative neuroradiologic studies in surgical patients with a herniated disk and/or degenerative cervical spondylosis. Twenty-six patients were enrolled: 16 of them underwent anterior diskectomy, 7 posterior decompressive laminectomy and 3 vertebral body removal. The patients were submitted to pre- and postoperative MRI with high field equipment (Signa 1.5 T, General Electrics), using sagittal SE T1- (TR/TE 360/15), PD and T2-weighted (TR/TE/FA 2000/40/120) sequences and T2-weighted GE axial sequences (TR/TE/FA 400/34/30). FSE sequences (TR/TE/ETL 4000/95/8) were used in 15 cases instead of the above T2-weighted SE sequences. The main postoperative MR findings were analyzed. In particular, the morphological and signal features of bone grafts, of vertebral end-plates, of the subchondral bone and of the surgical site were studied. After anterior diskectomy, the most frequent MR features were massive signal changes in the bone graft and lower vertebral plates, which were hypointense in T1 and hyperintense in T2; the adjacent subchondral bone also exhibited signal changes. Other postoperative MR findings accounted for early postoperative mobility (4 cases of persistent myelomalacia and 3 of bone graft fracture with consequent spinal instability) and late mobility (2 cases of herniated disk, 5 of spinal stenosis and one pseudomeningocele). The main limitation of MRI in postoperative cervical spine studies was the presence of ferromagnetic artifacts during SE, and even more GE, sequences; these artifacts were the main cause of misdiagnoses. In our experience, this troublesome limitation was overcome with FSE sequences but diagnostic accuracy remained poor in 4 patients. MRI, thanks to its multiparametric and multiplanar yield, is the gold standard for the examination of several early and late postoperative features and of postoperative mobility in the cervical spine. Moreover, T2-weighted FSE acquisitions are better than conventional SE to this purpose, because examination time is shorter, myelographic effect is improved and the sensitivity to ferromagnetic artifacts reduced.

Adult↗

In vivo visualization of pituitary dopaminergic receptors by iodine-123 methoxybenzamide (IBZM) correlates with sensitivity to dopamine agonists in two patients with macroprolactinomas.

We performed in two patients with macroprolactinoma, pituitary scintigraphy with 123 iodine-methoxybenzamide (IBZM), a dopaminergic antagonist that specifically binds to the D2 dopaminergic receptors. In a 34-yr-old woman with basal PRL levels of about 2000 ng/mL, 7.5 mg/day of Bromocriptine (Br) for a month neither reduced PRL levels nor affected tumor size; in this patient single photon emission tomography SPECT failed to show any pituitary accumulation of the tracer. In the other patient, a 27-yr-old man presenting with cerebrospinal fluid rhinorrhea, basal PRL levels were at 5000 ng/mL; magnetic resonance imaging (MRI) demonstrated a huge pituitary tumor, and SPECT showed a very intense concentration of IBZM at the level of the adenoma. PRL levels fell dramatically to 530 ng/mL with only 2.5 mg/day of Br after 4 days; after 6 days with 7.5 mg/day Br, PRL levels were 63 ng/mL, and the patient underwent surgery to correct cerebrospinal fluid leakage. We conclude that, in these two patients, the pituitary scintigraphy with IBZM has given information on the density of dopamine receptors on the adenoma and has correlated with the inhibitory effect of Br on PRL secretion. Whether this tool might be of value in identifying patients with pituitary tumors potentially responsive to Br treatment is still to be investigated.

Adult↗

[Diagnostic yield in rhino-sinusal inflammatory pathology: comparison of projective radiology, CT and MR].

In everyday practice, the radiologist is concerned with the diagnosis of inflammatory conditions of the nose and paranasal sinuses. This paper was aimed at evaluating and comparing the diagnostic efficacy of the main diagnostic imaging procedures currently available. Fifty-six patients were studied: 25 with computed radiography (CR) and CT, 21 with CR and MRI (0.22 T resistive magnet), and 10 with CR, CT, and MRI. From the diagnostic point of view, the conventional-like CR image was assumed as analog to the conventional radiographic (RX) one on the basis of previous personal experience. The following elements were separately considered for RX, CR, CT, and MRI: anatomical structure identificability, spatial resolution, dosimetry, time consumption, diagnostic results, and economics. A global performance index was calculated (RX less than 1; CR = 1; MRI ranging 1.2-2.2; CT = 7.3). CR was superior to RX, from both a diagnostic and a dosimetric point of view, but buying the equipment is nowadays expensive. CT and MRI were superior to both RX and CR in the diagnosis of inflammatory conditions of the nose and paranasal sinuses. When an inflammatory condition is unquestionable, MRI is more accurate than CT, but the latter (thanks to its optimal documentation of both bony walls and soft tissues) is superior to MRI in the differential diagnosis of a generic disease of the nose and paranasal sinuses--that is, when the inflammatory nature is questionable. MRI limitations were poor visualization of bone walls, high cost, and poor access. Thus, CT emerged as the technique of choice, thanks to its diagnostic results, easy access and low cost, with a negligible radiation dose to patients.

Adult↗

[Vertebral collapse model: combined diagnostic imaging].

Ninety-eight consecutive patients with 344 collapsed vertebrae underwent conventional and/or digital radiography and MRI. Vertebral collapse was due to osteopenia (16 cases), trauma (17 cases), and vertebral osteonecrosis (3 cases). Other causes were: spondylodiscitis (9 patients), primary neoplasm (4 patients), metastases (37 patients), and hemomyelopathies (7 patients); 5 patients bore vertebral angiomas. Sixty-three patients also underwent CT and 25 bone scintigraphy. As far as collapsed vertebral endplates are concerned, according to a previous classification, outcomes were divided into 4 groups. Type 1 (focal concave collapse) was observed in 10% of benign lesions and in 1% of malignant ones; type 2 (diffuse concave collapse) in 24% of benign and in 16% of malignant lesions; type 3 (focal collapse with an acute angle) in 11% of benign and malignant lesions, and type 4 (diffuse collapse with an acute angle) in 11% of benign and in 26% of malignant lesions. Neural arch involvement was observed in 3% of benign lesions and in 16% of malignant ones; paravertebral soft-tissue involvement in 6% of benign and in 29% of malignant lesions; vertebral canal involvement in 11% of benign lesions and in 20% of malignant ones. The intervertebral disk proximal to vertebral collapse was more involved in benign lesions (24%) than in malignant ones (8%). MR signal followed 4 main patterns: low signal on T1-weighted images and high signal on proton-density and T2-weighted images (2% of benign lesions, 49% of malignant ones), low signal on all sequences (7% of benign lesions and 25% of malignant ones), isointense signal on all sequences (50% of benign and 21% of malignant lesions), and high signal on all sequences (41% of benign lesions and 0% of malignant ones).

Adolescent↗

[High-resolution rapid multiplanar reconstructions in the CT study of the spine. Our experience].

The authors describe the utility of fast and high-resolution multiplanar CT reconstructions in the study of the rachis. Their experience is reported with an up-to-date software with 2 different representation modalities (CMR 01B). A "package" of contiguous axial images is obtained in a standard way; the images are then reformatted by computer to obtain (in just a few seconds) high-resolution reconstructed images in different planes (coronal, sagittal, and oblique). In the authors' opinion the method, in spite of some limitations, yields in most cases additional information which is not provided by conventional CT. Reconstructed images are most useful in the study of complex anatomical structures (such as vertebral metameres) along their anatomical planes.

Humans↗

[ERCP in the diagnosis of bilio-pancreatic pathology. Comparison with echography and CT].

The authors have evaluated both sensitivity and specificity of ERCP in comparison with other imaging methods, such as US and CT, on the basis of a study of 63 patients with suspected pancreatobiliary pathologies. Our results show ERCP of chronic pancreatitis to have 83% sensitivity and 66% specificity. As for biliary pathologies, sensitivity was 94% and specificity 88%. In pancreatic pathologies, CT sensitivity was 99% and its specificity was 70%. The combined use of ERCP and CT determines a considerable rise in the percentages, and allows the evaluation of both the excretory tree and the parenchyma. As for biliary pathologies, the role of ERCP is fundamental, since its combination with the other methods (CT: sensitivity 72%, specificity 3.5%; US: sensitivity 70%, specificity 3.5%) has not determined but a slight increase in sensitivity, and no significant increase in specificity.

Adult↗