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D A Graeb

Publications and source records attributed to D A Graeb.

At least 19 recordsLinked to original sources
PubMed2006

Diffusion-weighted imaging findings in Balo concentric sclerosis.

Balo concentric sclerosis is a rare demyelinating disease. Pathognomonic features have been previously described. Diffusion-wighted imaging findings have not been previously described in Balo concentric sclerosis. We describe the diffusion-weighted imaging findings in a 45-year-old lady with Balo concentric sclerosis. Diffusion-weighted imaging offers insight into the possible pathophysiology of this rare disease.

Diffuse Cerebral Sclerosis of Schilder↗
PubMed2006

Calcified cerebral emboli.

Intracranial calcifications may represent calcified cerebral emboli. Calcified emboli may be overlooked even though cerebral CT is widely used as a stroke assessment. We report 4 cases of calcified cerebral emboli and demonstrate the value of CT in the diagnosis and temporal evaluation of such emboli.

Aged↗
PubMed2001

Baló's concentric sclerosis: surviving normal myelin in a patient with a relapsing-remitting dinical course.

Baló's concentric sclerosis is a demyelinating disorder in which bands of demyelination alternate with concentric bands of myelin preservation. The pathogenesis of the lesion is unknown. Previous reports using modern histopathologic techniques have shown the bands of myelin preservation to be comprised of remyelinated or partially demyelinated myelin. Here we report a case of Baló's concentric sclerosis in a 24-year-old East Indian patient with a previous history of relapsing-remitting multiple sclerosis (MS). Pathologically, the bands of myelin preservation showed myelin sheaths of normal thickness, with focal areas of demyelination. The findings, taken together with those of previously reported cases, suggest that Baló's concentric sclerosis is a variant of MS, and the concentric lesion may be an intermediary form in evolution of a chronic active MS plaque. The pathogenesis of this concentric lesion may be explained by periodic suppression of demyelination in the rapidly expanding border, allowing remyelination or only transient incomplete demyelination to occur.

Adult↗
PubMed1997

In vivo measurement of T2 distributions and water contents in normal human brain.

Using a 32-echo imaging pulse sequence, T2 relaxation decay curves were acquired from five white- and six gray-matter brain structures outlined in 12 normal volunteers. The water contents of white and gray matter were 0.71 (0.01) and 0.83 (0.03) g/ml, respectively. All white-matter structures had significantly higher myelin water percentages (signal percentage with T2 between 10 and 50 ms) than all gray-matter structures. The range in geometric mean T2 of the main peak for both white and gray matter was from 70 to 86 ms. T2 distributions from the posterior internal capsules and splenium of the corpus callosum were significantly wider (width is related to water environment inhomogeneity) than those from any other white- or gray-matter structures. Thus, quantitative measurement and analysis of T2 relaxation reveals differences in brain tissue water environments not discernible on conventional MR images. These differences may make short T2 components reliable markers for normal myelin.

Adult↗
PubMed1992

Multidisciplinary approaches to complicated vascular lesions of the orbit.

BACKGROUND: Hemodynamically active vascular lesions of the orbit are often clinically challenging to treat, both because of the complexity of the vascular anatomy and the delicacy of the cardinal structures that are involved and vulnerable to damage. Attempts to achieve complete embolization of such vascular lesions may result in damage to vital visual structures. Conversely, incomplete closure of the feeders or vascular shunts will usually result in recanalization and, therefore, recurrence of such lesions. METHODS: Surgical excision after selective optimal embolizations may convert dynamic lesions into static ones with controlled surgical risks and could provide a solution to these problems. Cyanoacrylic polymerization was used to embolize the lesions, which were then excised with careful microsurgical and microvascular techniques. RESULTS: The authors present four cases of different hemodynamically active orbital vascular lesions (a post-traumatic arteriovenous fistula, a complex venous anomaly, a cavernous hemangioma of bone, and an arteriovenous malformation), which were treated successfully with the combination of presurgical embolization and surgery. CONCLUSION: The authors believe that, from their experience with these cases, a multidisciplinary approach to complicated orbital vascular lesions is ideal and practical.

Adult↗
PubMed1991

Carotid and vertebral artery trauma: clinical and angiographic features.

Injury to the carotid or vertebral artery is an important clinical entity that requires angiography for definitive diagnosis and evaluation. The common carotid artery may be injured by penetrating trauma while the internal carotid artery is usually damaged by either trivial or blunt trauma. With trivial trauma extracranial internal carotid artery dissection should be considered if there is unilateral headache, Horner's syndrome or delayed transient ischaemic attack, and intracranial dissection if a profound neurological defect occurs immediately following trauma. Injury to the internal carotid artery following blunt trauma includes dissection of the extracranial internal carotid artery, carotid-cavernous fistula and pseudoaneurysm formation. These should be considered in a patient with delayed neurological deficit, mandibular or skull fracture, a constellation of orbital signs or diffuse subarachnoid haemorrhage, respectively. Vertebral artery injury is less frequent. Dissection typically follows abrupt cervical rotation and occurs at C1-2, whereas penetrating trauma may involve either the proximal or distal vertebral artery and occlusion, arteriovenous fistula or pseudoaneurysm may be found. Endovascular techniques may be used in either the carotid or vertebral artery to close fistulae or occlude an extensively damaged vessel.

Adult↗
PubMed1991

Neurologic complications in allogeneic bone marrow transplant patients receiving cyclosporin.

Regimens using cyclosporin (CSP) and either methylprednisolone (MP) or methotrexate (MTX) have been useful in the prophylaxis of acute graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation (BMT). However, CSP produces a number of side effects, including neurologic toxicity. A retrospective review of recipients of 239 BMTs given CSP-based prophylactic regimens revealed that 10 patients (4.2%, 95% confidence interval 0% to 10.4%) experienced a syndrome characterized by hypertension, severe visual disturbances, seizures and occipital lobe density changes on brain computed tomography (nine patients) or nuclear magnetic resonance imaging (one patient). Neurologic findings were reversible in all cases, usually after temporary discontinuation of CSP. Univariate analysis identified the following risk factors for neurotoxicity: use of unrelated or HLA-mismatched related donors, administration of etoposide (VP-16) or total body irradiation as part of conditioning, use of corticosteroids for prophylaxis or treatment of acute GVHD, or development of either acute GVHD or clinically significant microangiopathic hemolytic anemia (MAHA) post-BMT. In multivariate analysis, the most important predictors were the use of VP-16 (p = 0.008), the use of a continuous infusion CSP plus MP prophylactic regimen for GVHD (p = 0.003) and the development of MAHA after BMT (p less than 0.001). The strong association with MAHA suggests that endothelial damage is related to the development of this complication.

Adolescent↗
PubMed1990

Balloon embolization of latrogenic aortocoronary arteriovenous fistula.

A detachable latex balloon was used to occlude an iatrogenic aortocoronary arterio-venous fistula. The aim of providing retrograde myocardial perfusion was not achieved to any significant degree because of rapid recruitment of collateral venous routes to the coronary sinus. This may have implications for the effectiveness of deliberate grafting of the coronary venous system with proximal venous ligation, as has been recommended when the coronary arterial system is small and diffusely diseased.

Angioplasty, Balloon, Coronary↗
PubMed1990

Orbital lymphangiomas: clinical, radiologic, and pathologic characteristics.

To assess the value of computed tomography (CT) in evaluation of orbital lymphangioma, the CT findings in 11 patients were retrospectively analyzed and correlated with the clinical, hemodynamic, surgical, and pathologic findings. The lesions were classified by location in three categories: superficial (n = 1), deep (n = 6), or combined (n = 6); the latter were evident earlier in life. The CT findings correlated well with the surgical and histologic findings. Orbital lymphangiomas were poorly defined lesions that crossed anatomic boundaries such as the conal fascia and orbital septum. Some degree of enhancement was the rule, ranging from scattered patchy areas to enhancement of the majority of the lesion. Areas of hemorrhage caused cystlike masses with rim enhancement. Preoperative identification of the vascular enhancing component at CT examination enables the surgeon to resect this area to prevent postoperative hemorrhage. High-resolution CT is of great value in the diagnosis and preoperative treatment planning of orbital lymphangioma.

Adolescent↗
PubMed1990

Graves orbitopathy: correlation of CT and clinical findings.

The clinical and high-resolution computed tomographic (CT) findings in 71 patients (142 orbits) with Graves orbitopathy and 20 healthy patients (40 orbits) were retrospectively reviewed. The orbits with orbitopathy were subgrouped at clinical examination into those with (n = 18) and those without (n = 124) optic neuropathy. Mean extraocular muscle diameters and the calculated muscle diameter index were significantly increased in all orbits with ophthalmopathy, particularly in those with optic neuropathy. Graves orbitopathy affected the superior muscle group (63.4%) more than the medial (61.3%) or inferior (57%) recti. The most common pattern of muscle involvement involved all five measured extraocular muscles. Solitary muscle involvement most frequently involved the superior muscle group (6.3%). Significant enlargements of the retrobulbar optic nerve sheath and superior ophthalmic vein were noted only in orbits with optic neuropathy. Anterior displacement of the lacrimal gland at CT correlated with clinical palpability and occurred more frequently in patients with optic neuropathy. Severe apical crowding was the most sensitive indication of optic neuropathy at CT.

Female↗
PubMed1987

Orbital dermoids: features on CT.

The computed tomographic (CT) features of orbital dermoids were retrospectively reviewed in 17 patients; 15 of the lesions were proved histologically. On the basis of clinical and CT features, the tumors were classified as superficial or deep. All but one were extraconal in location. Seven lesions appeared cystic; only six showed typical fat density. The presence of a margin or rim, often partially calcified, was identified in ten lesions. Irregular scalloping of adjacent bone was a highly suggestive feature, occurring with 11 dermoids. Other bone changes, such as linear defects, thinning, or sclerosis, also occurred. Superficial dermoids showed less apparent bone changes. An extraconal orbital lesion associated with adjacent bone thinning or notching should raise the possibility of a dermoid, especially if a rim with calcification is seen. The appearance is pathognomonic if fat density is also present.

Adolescent↗
PubMed1986

Value of intravenous contrast enhancement in the CT evaluation of intraspinal tumors.

The usefulness of intravenous contrast-enhanced CT in delineating intraspinal cord tumors has not been well documented. To determine if intradural spinal tumors enhance, if the location and type of tumor can be determined, and if a double dose of contrast material provides more information than a single dose, a retrospective study of 23 patients with proven intradural extramedullary or intramedullary tumors was performed. All the tumors studied with CT after intravenous contrast enhancement showed that most lesions (18/23) enhanced, contrary to published reports. Contrast-enhanced studies delineated the extent of the tumor, helping to separate solid and cystic components. The enhancement pattern of ependymomas and astrocytomas was similar, while schwannomas had a characteristic appearance. A double dose of intravenous contrast material had no apparent advantage over a single dose.

Adolescent↗
PubMed1986

Radiological and pathological aspects of dural arteriovenous fistulas. Case report.

A case of dural arteriovenous (AV) fistula is presented with detailed radiological and pathological findings. The complex hemodynamic alterations that may result from dural AV fistulas are described. Pathological examination in this case demonstrated widespread occlusion of the superior sagittal sinus with multiple abnormal fistulous communications between abnormal arteries and arterialized veins. A portion of the lesion resembled a recanalized blood clot, in support of the theory proposed by others that dural AV fistulas are acquired lesions.

Adult↗