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M T Modic

Publications and source records attributed to M T Modic.

At least 109 records · Page 6Linked to original sources
PubMed1983

Anatomic and functional imaging of congenital heart disease with digital subtraction angiography.

Digital subtraction angiography (DSA) of the heart was performed in 54 patients for the evaluation of congenital heart disorders. DSA produced high-quality diagnostic images and accurate physiologic shunt data that compared favorably with catheter angiography and nuclear medicine studies. Retrospective analysis of this series of patients indicated that DSA studies contributed sufficient information to shorten significantly or modify cardiac catheterization in 85% (79/93) of the defects that were identified. Interatrial septal defects were particularly well diagnosed, with identification occurring in 10 of 10 cases, whereas intraventricular septal defects were identified in only 6 of 9 patients. Evaluation of postsurgical patients was accurate in 19 of 20 cases.

Adolescent↗
PubMed1983

Intravenous digital subtraction angiography: peripheral versus central injection of contrast material.

Central and peripheral intravenous injections of contrast material for digital subtraction angiography were compared in 30 patients. With 40 ml of contrast material, visualization of the carotid bifurcations was as good with the peripheral as with the central injection. A more consistently high-quality examination of the small intracranial vessels was obtained with the central injection.

Arm↗
PubMed1983

Intra-arterial digital subtraction angiography of the head and neck.

Intra-arterial digital subtraction angiography (IA DSA) was compared with conventional film/screen angiography in 70 patients with suspected atherosclerotic disease or intracranial disease. It was found that, although the contrast detectability of IA DSA was superior to that of conventional angiography, its spatial resolution was not as great. In all 70 cases, however, the spatial resolution of IA DSA was satisfactory for diagnosis, and it is concluded that the increased spatial resolution of conventional angiography should be necessary only in rare circumstances. The main disadvantage of IA DSA is the smaller field size, and it has several advantages over conventional film/screen angiography: (a) it is safer, since less contrast material is needed to visualize large vessels; (b) costs are lower since the magnetic recording tape and hard copies result in a savings of between $45 and $140 per examination; and (c) there is less need for darkroom personnel and film storage.

Aorta, Thoracic↗
PubMed1983

Nuclear magnetic resonance imaging of the spine.

Forty subjects were examined to determine the accuracy and clinical usefulness of nuclear magnetic resonance (NMR) examination of the spine. The NMR images were compared with plain radiographs, high-resolution computed tomograms, and myelograms. The study included 15 patients with normal spinal cord anatomy and 25 patients whose pathological conditions included canal stenosis, herniated discs, metastatic tumors, primary cord tumor, trauma, Chiari malformations, syringomyelia, and developmental disorders. Saturation recovery images were best in differentiating between soft tissue and cerebrospinal fluid. NMR was excellent for the evaluation of the foramen magnum region and is presently the modality of choice for the diagnosis of syringomyelia and Chiari malformation. NMR was accurate in diagnosing spinal cord trauma and spinal canal block. The normal disc was seen, but with rare exceptions bulging of the annulus and herniation of the nucleus pulposus were not visualized.

Adolescent↗
PubMed1983

Magnetic resonance imaging of the cervical spine: technical and clinical observations.

Seventy-two patients were examined to determine the clinical potential for magnetic resonance imaging (MRI) of the spine. MRI using different pulse sequences was compared with plain radiography, high-resolution computed tomography, and myelography. There were 35 normal patients; pathologic conditions studied included canal stenosis, herniated disk, metastatic tumor, neurofibroma, trauma, Chiari malformation, syringomyelia, arteriovenous malformation, and rheumatoid arthritis. MRI provided sharply defined anatomic delineation and tissue characterization. It was diagnostic in syringomyelia and Chiari malformation and was useful in the evaluation of trauma and spinal canal block from any cause. MRI was sensitive to degenerative disk disease and infection. The spin-echo technique, with three pulse sequence variations, seems very promising. A short echo time (TE) produces the best signal-to-noise ratio and spatial resolution. Lengthening the TE enhances differentiation of various tissues by their signal intensity, while the combined increase of TE and recovery time (TR) produces selective enhancement of the cerebrospinal fluid signal intensity.

Arnold-Chiari Malformation↗
PubMed1983

Digital subtraction angiography in the evaluation of cerebrovascular disease.

Intravenous DSA provides a safe, accurate, and cost-effective means of examining the extracranial and intracranial vasculature on an inpatient or outpatient basis. Intra-arterial DSA provides better spatial resolution than IV-DSA and has advantages over conventional film-screen angiography. The authors demonstrate the applications and limitations of this revolutionary diagnostic technique.

Carotid Artery Diseases↗
PubMed1982

Intravenous digital subtraction angiography in brain ischemia.

Recent advances in computer and radiological technology have permitted a reassessment of intravenous (IV) angiography in the evaluation of extracranial and intracranial vessels. This report reviews our initial experience with IV digital subtraction angiography in the diagnosis and treatment of brain ischemia. Two hundred seventy-three IV digital subtraction angiograms (146 extracranial, 127 intracranial) were performed on a total of 178 patients with suspected cerebral ischemia (159 patients), brainstem/cerebellar ischemia (13 patients), or asymptomatic bruit (six patients). Extracranial studies clearly demonstrated ulceration, stenosis, and occlusion of the carotid arteries. Intracranial studies usually detected major artery occlusive disease and provided insight into the collateral flow patterns. Intravenous digital subtraction angiography allowed the accurate assessment of arteries after carotid endarterectomy and brain bypass surgery. Although conventional angiography was usually recommend in patients treated surgically, IV digital subtraction angiography obviated the need for conventional studies in the initial evaluation of many patients.

Arterial Occlusive Diseases↗
PubMed1982

The use of digital subtraction angiography in the evaluation of carotid cavernous sinus fistulas.

Intravenous digital subtraction angiography (IV-DSA) is a safe, rapid procedure that can be performed on an outpatient basis and provide diagnostic information comparable to conventional angiography. This paper reviews the initial experience with intravenous digital subtraction angiography in the evaluation of five cases of carotid cavernous sinus fistula, digital subtraction angiography.

Angiography↗
PubMed1982

Sector computed tomographic spine scanning in the diagnosis of lumbar nerve root entrapment.

The diagnosis of lumbar nerve root entrapment was made by sector computed tomography (CT) scanning in 25 patients whose myelograms were normal at the site of the CT scan abnormalities. Sector CT scanning demonstrates preoperatively which neural foramina are narrow. This information, correlated with the patient's history and physical examination, indicates which foramina should be operated on and prevents unnecessary exploration of normal neural foramina. CT findings were confirmed surgically in 14 patients. Eleven of these 14 patients had excellent postoperative results and remain pain free.

Adult↗
PubMed1982

Hemorrhage and anticoagulation after nonseptic embolic brain infarction.

Among 54 consecutive patients with acute nonseptic embolic brain infarction, there was CT evidence of hemorrhagic infarction in 1 patient (2%). None had clinical or CT evidence of massive brain hemorrhage even when anticoagulation therapy was used immediately. Seven patients (13%) had recurrent brain emboli, all within 7 days of the initial stroke. None of these patients was adequately anticoagulated at the time of recurrence. Immediate anticoagulation therapy should be employed after nonseptic embolic brain infarction if CT does not show hemorrhage and there is a persistent cardiac source of emboli.

Cerebral Hemorrhage↗
PubMed1982

Digital subtraction angiography of the intracranial vascular system: comparative study in 55 patients.

Intracranial vessels were examined in 55 patients with both conventional selective catheterization and intravenous digital subtraction angiography using a prototype digital subtraction unit. In 65% of the patients, the digital subtraction angiogram was diagnostic, but the overall quality was inferior to conventional selective angiography. In 22%, the digital subtraction angiogram provided diagnostic information, but there was a significant chance of misinterpreting the results of the study. In 13% of cases, the subtraction angiogram was not diagnostic. As now developed, digital subtraction angiography can replace conventional cerebral angiography for preoperative evaluation of the juxtasellar carotid artery prior to transphenoidal surgery because the large intracerebral vessels are consistently well visualized with digital subtraction. The dural sinuses are better visualized with digital subtraction than with conventional angiography because with digital subtraction all the vessels of the brain are opacified, whereas with conventional angiography, there is a mixture of opacified and unopacified blood in the sinuses. Combined with computed tomography, digital subtraction angiography can replace conventional angiography for determining the preoperative extent and vascularity of tumors. It can be used for postoperative evaluation of aneurysms, arteriovenous malformations, extracranial to intracranial bypasses, and after the embolization of vascular lesions.

Adult↗
PubMed1982

Intravenous digital subtraction angiography in neuro-ophthalmology.

The development of computer reconstructed images of the extracranial and intracranial vessels after injecting modest doses of intravenous contrast media has significantly altered standard angiography procedures. Intravenous digital subtraction angiography is a reproducible and rapid outpatient procedure that is less expensive and safer than conventional arteriography. The applications and limitations of this new technique to neuro-ophthalmology are discussed.

Adult↗
PubMed1982

Early patency of the carotid artery after endarterectomy: digital subtraction angiography after two hundred sixty-two operations.

During a 12-month period of study, 265 patients (mean age 65 years) underwent a total of 314 carotid endarterectomies for the management of previous transient cerebral ischemia (39%), prior stroke (10%), or severe asymptomatic carotid stenosis (51%). Five patients (1.6%) died within 30 days of operation, but only three deaths (1%) were related to carotid reconstruction. Six patients (1.9%) experienced postoperative strokes, including 1.6% of those with previous transient ischemia, 9.7% of those with prior strokes (P less than 0.02), and 0.6% of those with asymptomatic carotid stenosis before operation. Digital subtraction angiography (DSA) was performed during the same hospital admission following 262 procedures in a group of 214 patients, including all patients who had postoperative neurologic complications. Seven of these operations were limited to external carotid endarterectomy. The internal carotid artery was entirely normal in 239 (94%) of the remaining 255 DSA studies. The external carotid artery was normal on 238 (93%) of 255 DSA examinations, but was occluded on 12 (4.7%). A focal intimal defect corresponding to the apical arteriotomy suture was found in nine internal carotid arteries (3.6%), but these lesions did not appear to be hemodynamically significant. The internal carotid artery contained over 30% stenosis in two patients (0.8%) and was occluded in five (1.9%). Two of these five patients had neurologic complications, but four others with operative strokes had normal angiograms. Asymptomatic postoperative thrombosis of the internal carotid artery was documented in only three patients (1.2%).

Adult↗
PubMed1981

Visualization of the arteries, veins, and nerves of the orbit by sector computed tomography.

Altering the scintillation crystal configuration of a fixed-detector CT scanner increased the spatial resolution from 6.25 to 10 line pairs per centimeter. Sector scans of th orbit with this modified scanner showed the ophthalmic artery and superior ophthalmic vein and their branches and the intraorbital branches of the third, fifth, and sixth nerves, apparently seen with CT for the first time.

Humans↗