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S Destian

Publications and source records attributed to S Destian.

17 recordsLinked to original sources
PubMed1997

Internally stabilized spine: optimal choice of frequency-encoding gradient direction during MR imaging minimizes susceptibility artifact from titanium vertebral body screws.

In 18 vertebral bodies with titanium fixation screws and in a phantom model, visualization of the vertebral body marrow was improved and susceptibility artifact was reduced on T1-weighted spin-echo magnetic resonance images when the direction of the frequency-encoding gradient was parallel to the long axis of the screw. A perpendicular direction improved image quality only when the region of interest was adjacent to the tip of the screw. In the phantom, the length of the screw was statistically significantly increased and the width and area were reduced (P <.001) when the gradient was parallel to the long axis of the screw.

Adult↗
PubMed1994

Giant infectious intracavernous carotid artery aneurysm presenting as intractable epistaxis.

Infectious intracavernous carotid artery aneurysms usually present with ophthalmoplegia and/or signs of cavernous sinus thrombosis. We report an unusual case in which a patient with AIDS presented with intractable epistaxis secondary to rupture of a giant infectious intracavernous carotid artery aneurysm. Culture of the aneurysm grew mycobacterium avium intracellulare (MAI). The patient was treated successfully by excision of the aneurysm and reconstruction of the internal carotid artery with a saphenous vein interposition graft.

AIDS-Related Opportunistic Infections↗
PubMed1993

Spinal tuberculosis: atypical observations at MR imaging.

PURPOSE: To evaluate atypical magnetic resonance (MR) imaging features of spinal tuberculosis. MATERIALS AND METHODS: Between 1990 and 1993, five of 11 consecutive patients with spinal tuberculosis (two men and three women, aged 30-57 years) had MR findings more suggestive of neoplasm than infection. One patient, a European immigrant, had acquired immunodeficiency syndrome (AIDS). RESULTS: Areas involved with tuberculosis were hypointense on T1-weighted images and hyperintense on T2-weighted images, and became enhanced with gadopentetate dimeglumine. In two patients, tuberculosis affected only a single vertebral body without paraspinal abscesses or involvement of the end plates and disk spaces. In two other patients, only a single spinous process was replaced with tuberculous abscess. In the remaining patient, the sacrum and multiple lower lumbar vertebrae were affected, but the intervertebral disk spaces were not affected. More typical findings of spinal tuberculosis include destruction of two adjacent vertebral bodies and opposing end plates, destruction of intervening disk space, and/or occurrence of paravertebral abscesses. CONCLUSION: Neither clinical examination nor MR findings may be reliable in helping differentiate spinal infections from one another or from neoplasm. Adequate biopsy is essential for early diagnosis and prompt treatment.

Abscess↗
PubMed1993

Monitoring of infectious intracranial aneurysms by sequential computed tomographic/magnetic resonance imaging studies.

To monitor the course of infectious intracranial aneurysms, repeated cerebral angiography has been recommended every 2 weeks during intravenous antibiotic therapy until the aneurysm has resolved or an operation has been performed. However, serial cerebral angiograms are not without some risk to the patient. We have prospectively studied five patients harboring a total of six infectious intracranial aneurysms by sequential computed tomography (CT) and/or magnetic resonance imaging (MRI) studies. All infectious aneurysms were initially identified by cerebral angiography and were treated with 6 to 8 weeks of intravenous antibiotics. The aneurysm size ranged from 4 to 10 mm. Sequential CT scans and/or MRI studies were obtained at 2- to 3-week intervals to monitor the course of the aneurysms. Three aneurysms enlarged during antibiotic therapy, and one remained unchanged in size. These four aneurysms were treated surgically. The two remaining aneurysms resolved with intravenous antibiotic therapy. Cerebral angiograms were obtained routinely preoperatively and were used to verify the resolution of the infectious aneurysms when they were no longer visible on CT or MRI. On the basis of this prospective study, we conclude that sequential thin-slice CT and/or MRI can effectively and safely monitor the course of infectious intracranial aneurysms once identified by cerebral angiography. This may reduce the need for serial angiography and reduce the ultimate risk in the management of infectious intracranial aneurysms.

Adult↗
PubMed1992

Cystic fluid in craniopharyngiomas: MR imaging and quantitative analysis.

A prospective study of cystic fluid in craniopharyngiomas in 10 patients was performed to correlate signal intensity on T1-weighted magnetic resonance (MR) images and biochemical analysis. Within 2 days before surgery, each patient underwent MR imaging before and after administration of gadopentetate dimeglumine. Five patients had cystic fluid lower in signal intensity than white matter, with protein levels less than 9,000 mg/dL (90.00 g/L) and no free methemoglobin. One of the five patients had the highest triglyceride concentration (84 mg/dL [0.95 mmol/L]) of all 10 patients; another of these five had the highest cholesterol concentration of all (270 mg/dL [6.98 mmol/L]). It is concluded that the increased signal intensity of cystic fluid in craniopharyngiomas on T1-weighted MR images can be caused by a protein concentration greater than or equal to 9,000 mg/dL (90.00 g/L), the presence of free methemoglobin, or both. In the ranges of concentrations measured in this study, cholesterol and triglyceride did not increase signal intensity.

Adolescent↗
PubMed1992

The Consortium to Establish a Registry for Alzheimer's Disease (CERAD). Part III. Reliability of a standardized MRI evaluation of Alzheimer's disease.

The Consortium to Establish a Registry for Alzheimer's Disease (CERAD) has developed procedures for standardized imaging and reporting of magnetic resonance (MR) findings in Alzheimer's disease (AD) for use by neuroradiologists in multiple medical centers using a variety of MR equipment and field strengths. After initial pretesting, we revised the protocol, expanded the summary rating scale to seven points, and added more illustrations. Fourteen participating neuroradiologists evaluated 28 MR scans of elderly patients, giving us the basis for judging interrater agreement. We obtained acceptable intraclass correlations (greater than 0.79) for rating the size of the lateral and third ventricles and the temporal horn. Less satisfactory intraclass correlations occurred when rating other areas, including (1) global atrophy of the brain (0.70); (2) dilatation of the sulci of the temporal lobe (0.66); (3) frequency, location, and severity of white matter lesions (0.77); (4) sylvian fissure enlargement (0.70); and (5) cerebral sulcal dilatation (0.64). We also saw considerable variation in the reporting of cortical and lacunar infarcts. Despite careful design of the rating methodology and readings by experienced neuroradiologists, we did not find satisfactory interrater agreement for interpreting MR findings in elderly subjects. These findings may explain the difficulties encountered in applying similar subjective rating techniques that meet with success at one institution to multicenter studies. More objective and reproducible procedures are needed for interpretation of neuroimaging findings of AD in multicenter studies.

Alzheimer Disease↗
PubMed1992

Magnetic resonance imaging of meningiomas.

MRI with gadolinium enhancement is the imaging modality of choice in the diagnosis of meningiomas. Various MRI features are described. MRI signal intensity characteristics in meningiomas contain information that could be correlated with the histopathology of the tumor. Hyperintensity on T2-weighted images indicates soft tumor consistency and microhypervascularity and is more often seen in aggressive, angioblastic, or meningothelial meningiomas. MRI is useful in demonstrating dural sinus involvement. Meningiomas in unusual locations and their mimics are also presented.

Brain↗
PubMed1990

MRI of the skull.

Thirty-four patients with a wide variety of benign and malignant incidental skull findings on routine magnetic resonance (MR) imaging of the brain were reviewed. In most instances detection of the lesions was not difficult. However, recognition of various patterns of skull involvement in different disease processes is important. This is particularly true in differentiating benign from malignant lesions, which may be a critical factor in patient management.

Adolescent↗
PubMed1989

MR imaging of hemorrhagic intracranial neoplasms.

Thirty patients with intracranial tumors containing hemorrhage of varying stages were examined with high-field-strength MR imaging and CT to determine what differences might exist between hemorrhagic tumor and pure hemorrhage. Pathology was obtained in the six patients with primary tumors and in 14 of the 24 patients with metastases. Similar to evolving intraparenchymal hematomas, hemorrhagic neoplasms undergo changes in their appearance that can be categorized into three distinct intensity patterns, or stages. Stage 1 is characterized as iso- or hypointensity on short TR sequences and as hypointensity on long TR sequences; stage 2 as developing hyperintensity on both short and long TR sequences, without evidence of a well-defined black rim; and stage 3 as a hyperintense lesion with a well-defined black rim on long TR sequences. An additional mixed-intensity pattern was identified, which contained areas corresponding to more than one stage. In all of the cases exhibiting this pattern, pathology confirmed that the appearance was due to recurrent bleeding. We found several characteristics on MR that, when present, suggest an underlying neoplasm. These include delay in evolution between stages, central or eccentric hyperintensity in stage 2, and a mixed-intensity pattern. In addition, the presence of a hemosiderin rim does not exclude an underlying neoplasm. We found that the MR patterns that characterize hemorrhagic intracranial neoplasms should help to determine the cause of the hemorrhage.

Adult↗
PubMed1989

Head trauma.

Computed tomography is currently the modality of choice in imaging acutely traumatized patients. This is based upon CT's documented ability to detect surgically significant lesions. Furthermore, the use of MRI is limited by a lack of bone detail, the degradation of MR images in frequently uncooperative patients, and a limited supply of nonferromagnetic monitoring equipments. CT and MRI are largely equivalent in their ability to diagnose epidural hematoma, but CT is readily available and quick. MRI provides information in addition to that obtained by CT in many instances, such as subacute and chronic subdural hematomas, contusions, and intracerebral hematomas.

Brain Injuries↗
PubMed1986

Aggressive angiomyxoma: CT appearance.

Aggressive angiomyxoma is a rare benign tumor, arising in the pelvis usually presenting clinically as a perineal soft tissue mass displacing normal pelvic structures. The tumor is characterized by its locally aggressive nature and its tendency to recur after surgical resection. Although descriptions of this tumor have recently appeared in the pathology literature, to date, the radiological appearance of aggressive angiomyxoma has not been well documented. The CT scan in the following case report demonstrates the extent and location of the tumor, as well as its tendency to displace, rather than invade adjacent structures. These findings are consistent with the pathological characteristics of aggressive angiomyxoma, and therefore, can assist in its preoperative diagnosis.

Adult↗
PubMedDate not supplied

MR imaging of pineal region neoplasms.

Twenty-eight patients with tumor of the pineal region underwent magnetic resonance (MR) examination. Gadolinium DTPA was given to 13 patients. Histologic confirmation was obtained in all patients, including 10 germinomas, 4 pineocytomas, 4 pineoblastomas, 5 astrocytomas, 2 teratomas, 1 choriocarcinoma, 1 mixed germ cell tumor, and 1 metastasis from breast carcinoma. Pineal region neoplasms have remarkable heterogeneity in both histopathologic and MR appearances. Gadolinium DTPA enhanced MR increases the specificity of diagnosing pineal region neoplasms. In addition, Gd-DTPA provides better delineation of the tumor margin and demonstrates cystic components of the neoplasm. Our approach to pineal region neoplasms is to make a decision about whether stereotaxic biopsy or surgery should be performed on a certain patient. When a pineal region neoplasm is diagnosed as benign, such as a benign teratoma, on the basis of imaging, surgery is performed to resect the entire lesion. When a definitive diagnosis is not possible, sterotaxic biopsy is performed to obtain histological diagnosis for treatment planning. Gadolinium DTPA enhanced MR plays an extremely important role in target selection in stereotaxic biopsy of pineal region neoplasms and is also useful in the early detection of intracranial seeding. Spinal seeding is demonstrated on MR as well, thus alleviating the need for a contrast myelogram. Finally, Gd-DTPA enhanced MR can be used to monitor the effects of the various treatment modalities employed for pineal region neoplasms.

Adolescent↗
PubMedDate not supplied

SPIR MRI in spinal diseases.

We report on our experience with the fat suppression technique of spectral presaturation with inversion recovery MR in imaging certain spinal disorders. This technique may assist in demonstrating or excluding the presence of fat within a lesion (such as lipoma, dermoid, teratoma) or within a normal structure (i.e., vertebral body or epidural space). The method can also be used to suppress normal fat (such as marrow or epidural fat) thus increasing the conspicuity of adjacent high signal intensity lesions seen on T1-weighted images (such as blood and contrast-enhancing tumors or inflammatory lesions).

Abscess↗
PubMedDate not supplied

MRI of intraventricular cysticercosis: surgical implications.

OBJECTIVE: Our goal was to evaluate the role of Gd-enhanced MR in the diagnosis and surgical planning of intraventricular cysticercosis cysts. MATERIALS AND METHODS: Thirty-three patients with intraventricular cysticercosis were evaluated with Gd-enhanced MRI including follow-up studies ranging over time periods from 6 months to 8 years. The patient age ranged from 17 to 65 years. All had lived in Mexico or Central America. RESULTS: Twenty patients had surgical removal of the cysts. The majority of patients (18 of 20) who had surgical removal of the cyst showed improvement with resolution of hydrocephalus. Two of 20 patients required additional shunting to alleviate hydrocephalus. In these two patients, Gd-enhanced MR showed cyst wall enhancement. Ependymitis with adhesion was found at surgery in these two patients. Nine patients had shunt placement; one of nine patients showed cyst enlargement 2.5 years later that required surgical removal. Of the remaining eight patients, four showed irregular, thick, ring-like enhancement mimicking a neoplasm on follow-up imaging studies. Four patients with cysts in the lateral ventricle did not require treatment. Two of the four patients showed irregular, thick, ring-like enhancement on follow-up imaging studies. CONCLUSION: Gadolinium-enhanced MR is more sensitive than contrast-enhanced CT for detecting ependymitis, which is essential in deciding whether surgical removal of the cyst or shunt placement is indicated. A degenerating intraventricular cysticercosis cyst may present as an irregular, thick, ring-like enhancing lesion or a nodular enhancing lesion with varying degrees of surrounding edema, mimicking a neoplasm.

Adolescent↗
PubMedDate not supplied

Differentiation between meningeal fibrosis and chronic subdural hematoma after ventricular shunting: value of enhanced CT and MR scans.

Unenhanced CT in four patients with long-standing ventricular shunts demonstrated bilateral low-density extraaxial collections that were indistinguishable from chronic subdural hematomas. After administration of contrast material, however, there was marked enhancement of the collections as well as prominent paratentorial and parafalcial enhancement. MR imaging, performed in three patients, demonstrated the extent and paradural location of the collections better than CT did, but, as with unenhanced CT, the collections could not be distinguished from chronic subdural hematomas. On follow-up CT and MR, there was no change in the size, enhancement, or intensity of the collections. Histologic examination of biopsies from two patients demonstrated fibrosis of the meninges characterized by granulation tissue and collagen deposition. Meningeal fibrosis is a rare postshunt phenomenon that may mimic chronic subdural hematoma on unenhanced CT and MR. Recognition of this entity is important, particularly if therapeutic intervention is being considered. Therefore, an enhanced CT or enhanced MR scan should be obtained in chronically shunted patients to differentiate between a drainable chronic subdural hematoma and meningeal fibrosis.

Adult↗