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M Lidov

Publications and source records attributed to M Lidov.

At least 19 recordsLinked to original sources
PubMed2001

Vertebral artery dissection in Turner's syndrome: diagnosis by magnetic resonance imaging.

Aortic artery dissection is a rare but well-recognized complication of Turner's syndrome. Isolated carotid or vertebral artery dissection has not previously been reported. The authors report the clinical and magnetic resonance imaging findings in a 30-year-old woman with Turner's syndrome who developed a high cervical spinal cord infarction with a Brown-Sequard syndrome owing to bilateral vertebral artery dissection. The diagnosis and management of the case is reviewed.

Adult↗
PubMed1997

Venous architecture of cerebral hemispheric white matter and comments on pathogenesis of medullary venous and other cerebral vascular malformations.

The parenchymal veins, especially the deep medullary veins, of the cerebral hemispheres were studied in detail by analyzing the stereoroentgenograms of multiple brain slices of postmortem injected brain specimens (injected into the internal carotid arteries in 17 cases and into the jugular veins in 12 cases). The presence of four zones--the first (or outer), the second (or candelabra), the third (or palmate) and the fourth (or subependymal) zone--of venous convergence was confirmed within the centrum semiovale, particularly in the frontoparietal area. Other venous convergences such as those related to the optic radiation in the para-atrial area were also found. Arterial branching zones were also observed in the areas similar to those of the medullary veins. It appears that these converging zones are created by rapidly growing crossing nerve fiber tracts, i.e., projection, commissural, and association fibers which grow rapidly during intrauterine and postnatal life. Pathogenesis of medullary venous malformation is also discussed from anatomical viewpoint, venoarchitecture of the pial, parenchymal, and subependymal veins and of the dural venous sinuses. The possibility of a similar mechanism (partial, mild, repetitive venoocclusive disease developing over a long period with fluctuating venous pressure) leading to formation of most (if not all) cases of medullary venous malformation and in some, if not many, cases of cerebral vascular malformations [aside from gene abnormality (chromosome 7) in familial cavernous angiomatosis, particularly in Hispanic American or other familial hereditary conditions] has been postulated.

Cerebral Cortex↗
PubMed1996

Reversible cerebral perfusion abnormalities associated with cyclosporine therapy in orthotopic liver transplantation.

A 60-yr-old woman experienced several episodes of generalized seizures following 2 wk of immunosuppressive therapy with cyclosporine for orthotopic liver transplantation. CT showed low density in the white matter of the parieto-occipital lobes. A 99mTc-HMPAO brain SPECT showed diminished perfusion in the parieto-occipital cortex bilaterally. Although the cyclosporine was discontinued, the patient's neurologic status initially worsened and then improved over the next several days. Repeat perfusion brain SPECT showed resolution of most of the perfusion abnormalities, while repeat CT showed persistent white matter changes in the parieto-occipital lobes. We report the presence of reversible cortical perfusion abnormalities in conjunction with cyclosporine therapy. The findings suggest that perfusion brain SPECT may be a sensitive monitor of cyclosporine-induced neurotoxicity.

Brain↗
PubMed1995

Symptomatic spinal epidural lipomatosis in a patient with Cushing's disease.

Spinal epidural lipomatosis (SEL) is a rare complication of iatrogenic Cushing's syndrome (CS). There is only one case reported of symptomatic SEL in association with endogenous CS. We present a patient with compressive myeloradiculopathy due to SEL and Cushing's disease and suggest that in SEL of hypercortisolism, the excess of corticosteroids is the stimulus for the growth of adipose tissue in the spinal canal and that treatment should be aimed at correcting the endocrine abnormality.

Adult↗
PubMed1994

Sinonasal esthesioneuroblastoma with intracranial extension: marginal tumor cysts as a diagnostic MR finding.

PURPOSE: To determine whether the MR finding of cysts along the intracranial margin of sinonasal esthesioneuroblastomas can be considered to suggest this tumor. METHODS: MR scans of 54 patients who had sinonasal lesions with intracranial extension were examined specifically for cysts along the intracranial margins of the lesions. RESULTS: Only 3 of the 54 patients had these cysts, and all 3 of these patients had esthesioneuroblastoma. Surgical pathologic findings of one specimen showed the cyst to be marginally located within the tumor. CONCLUSION: If cysts are seen on MR along the intracranial margin of a sinonasal mass, this finding highly suggests esthesioneuroblastoma.

Biopsy↗
PubMed1994

The significance of sinonasal radiodensities: ossification, calcification, or residual bone?

PURPOSE: To determine whether very radiodense material within a sinonasal soft-tissue mass on CT can be differentiated as calcification, ossification, or residual bone. METHODS: We retrospectively described the radiodensities within 235 sinonasal soft-tissue masses as discrete, solitary or multiple, or as a diffuse process with either a well-defined or poorly defined margin. They were also classified as calcification, ossification, or residual bone. Findings were correlated with pathologic specimens. RESULTS: Residual bone was underdiagnosed; calcification was overdiagnosed. A solitary discrete density was most likely to be calcification within an inflammatory mass. However, multiple discrete densities were as likely to be in a tumor as in an inflammatory lesion. If the process was diffuse with a well-defined margin, it was most likely to be a benign fibroosseous lesion. If the process was diffuse with a poorly defined margin, it was most likely to be a high-grade sarcoma. Densities within inverted papillomas were shown to be residual bone, not calcifications; densities within esthesioneuroblastomas were calcifications. CONCLUSION: Radiodensities may help in refining a CT diagnosis, but one may not know based on CT whether the density is a calcification, ossification, or residual bone.

Calcinosis↗
PubMed1994

The varied presentations of papillary thyroid carcinoma cervical nodal disease: CT and MR findings.

PURPOSE: To review the varied presentations of metastatic cervical lymph node disease in patients with papillary thyroid carcinoma. METHODS: Thirteen cases were retrospectively collected and their clinical, imaging, surgical, and pathologic material was reviewed. In the cases reviewed there was no clinical or imaging evidence of a primary thyroid mass. RESULTS: On CT, metastatic nodes can have multiple discrete calcifications, appear as benign cysts or hyperplastic or hypervascular nodes, or have areas of high attenuation which reflect intranodal hemorrhage and/or high concentrations of thyroglobulin. On MR, the nodes can have low to intermediate T1- and high T2-weighted signal intensities or high T1- and T2-weighted signal intensities, the latter reflecting primarily a high thyroglobulin content. CONCLUSION: If any of these varied appearances of cervical lymph nodes are identified on CT or MR, especially in a woman between 20 and 40 years of age, the radiologist should suspect the diagnosis of papillary thyroid carcinoma, even in the absence of a thyroid mass.

Adult↗
PubMed1993

Neurosarcoidosis presenting as a tumour of the basal ganglia and brainstem: sequential MRI.

Neurosarcoidosis may spread from the basal leptomeninges via the Virchow-Robin spaces to form intraparenchymal masses. We present a case of sarcoidosis whose first presentation was that of secondary amenorrhoea without other neurological symptoms. Discovery of a mass invading the basal ganglia, hypothalamus, pituitary stalk and midbrain led to a search for systemic involvement. After the diagnosis was proven by mediastinal biopsy, steroids were used effectively to shrink the tumour. Sequential magnetic resonance imaging (MRI) studies demonstrate dramatic reduction in the mass over a six month period. A high index of suspicion for sarcoidosis in intracranial masses, particularly in young adults, is advocated.

Adult↗
PubMed1993

Imaging the postoperative neck.

The variety of cervical lymphadenectomy and neck reconstructive procedures that have been developed in the past 20 years has led to confusion about nomenclature in the literature. In addition, some of these operations result in gross alteration of the normal anatomy. The authors review the present classification system for cervical lymph nodes and various lymphadenectomy and reconstructive procedures. Examples of typical postoperative images are given. A protocol for postoperative follow-up is presented, which calls for imaging for 5 years after surgery. Finally, the authors review their experience with 400 cases, 276 of which were initially classified as having no clinical evidence of disease. Recurrence developed in 68 of these (in 62 [91%] within 4-18 months of surgery). Imaging findings altered the postoperative salvage plan in 17 (25%). Clinically occult disease was found at sectional imaging in 47 (17%).

Head and Neck Neoplasms↗
PubMed1990

Calcified sphenoid mucocele.

Sphenoid sinus mucoceles are uncommon lesions, and may rarely contain calcifications within their wall. We describe a new appearance of this lesion--sphenoid sinus mucocele with gross calcifications within its matrix.

Aged↗
PubMed1990

Hypointense paranasal sinus foci: differential diagnosis with MR imaging and relation to CT findings.

Despite the plethora of information provided by magnetic resonance (MR) imaging that allows differentiation of some substances that are indistinguishable at computed tomography (CT), there are diagnostic problems. In particular, there are several quite disparate substances that all appear as either low signal intensity or signal void on T1-weighted images and even lower signal intensity or signal void on T2-weighted images. These substances include air, desiccated secretion, mycetomas, acute hemorrhage, calcium, bone, and enamel. When they are surrounded by material that has long T1 and T2 relaxation times, a not uncommon MR appearance in the sinonasal cavities, they may be impossible to differentiate from one another. The current explanations for the low signal intensities are presented, the similarities in the MR appearance are illustrated, and the use of CT to resolve diagnostic problems is discussed. CT appears to be the best modality for initially examining patients with suspected routine inflammatory disease or fungal infection.

Aspergillosis↗
PubMed1989

Benign and malignant sinonasal lesions with intracranial extension: differentiation with MR imaging.

Most sinonasal lesions that extend into the anterior cranial fossa are malignant tumors. However, benign inflammatory polypoid disease can also rarely be manifested in this manner. Fourteen surgically proved cases of such benign and malignant disease were studied with magnetic resonance (MR) imaging. The appearances of the benign and the malignant lesions were quite different and allowed the seven chronic polypoid lesions to be distinguished from the tumors. The benign lesions had nonhomogeneous appearances on MR images due primarily to varying degrees of free-water resorption and protein concentration. The tumors had primarily homogeneous low-to-intermediate signal intensities due to their highly cellular composition.

Carcinoma, Squamous Cell↗
PubMed1989

MR imaging of intracranial fluid levels.

Six patients with seven intracranial fluid levels were evaluated with both CT and MR at 1.5 T. A surgical diagnosis was obtained in six of the seven instances. MR was found to be superior to CT in detecting intracranial fluid levels, and the MR signal characteristics were helpful in identifying their contents. These cases demonstrate the necessity for a slightly different approach to lesions with fluid levels. In one patient, imaging in the prone position allowed detection of a solid component; in several others, detection of the fluid level was dependent on the selection of nonroutine windows and levels. Fluid levels are classified with respect to their components and MR features. MR is superior to CT in imaging fluid levels. The appearance of fluid levels on MR varies with their composition, the ratio of the components, the sequence parameters, and the position of the patient.

Adolescent↗
PubMedDate not supplied

MRI of lumbar intradural disc herniation.

We present the magnetic resonance imaging (MRI) appearance of a patient with an intradural lumbar disc herniation and discuss this entity. This case demonstrates the role of MRI in comparison to myelography/postmyelogram computed tomography with respect to the diagnosis of intradural disc herniation.

Female↗
PubMedDate not supplied

Hemorrhaged cystic hygroma and facial nerve paralysis: CT and MR findings.

The association of peripheral facial nerve paralysis and cystic hygroma is rare, this being only the third reported case. In this patient paralysis was secondary to hemorrhage within the cyst and nerve compression. Although the magnetic resonance studies allowed the diagnosis to be made eventually, the complex signal intensities due to excessive bleeding within the cyst confused the issue. In this case, CT allowed an immediate diagnosis to be established.

Adult↗
PubMedDate not supplied

Eccentric cystic facial schwannoma: CT and MR features.

Facial schwannomas are uncommon lesions with a fairly characteristic range of clinical and radiographic presentations. This report describes an unusual case of facial schwannoma that clinically and radiographically mimicked a cystic skull base lesion extrinsically compressing the facial nerve. The MR findings are presented.

Cranial Nerve Neoplasms↗
PubMedDate not supplied

Giant intracranial aneurysms with skull base erosion and extracranial masses: CT and MR findings.

OBJECTIVE: To present the CT and MR findings of three patients with giant intracranial aneurysms (GIAs), each of which eroded the skull base and had an extracranial mass component. A literature review of GIAs was also performed. MATERIALS AND METHODS: In the past year the imaging studies of three patients with these unusual GIAs were collected at our institutions. All three patients had had CT, and one patient had had MR on a 1.5 T GE unit. RESULTS: One patient had a 5 cm GIA in the left petrocavernous region, filling the middle cranial fossa and extending into the left sphenoid sinus and the left posterior ethmoid complex. The aneurysm had heterogeneous high attenuation and extensive rim calcification. The second patient had a 5 cm GIA that filled most of the left middle cranial fossa, eroding the floor and lateral wall and extending into the infratemporal fossa and parapharyngeal space. The aneurysm was partially thrombosed and had minimal rim calcification. The third patient had a 4 cm left cavernous GIA that eroded the floor of the middle cranial fossa and extended into the subjacent parapharyngeal space. The lesion was partially thrombosed and had an enhancing lumen. The rim had low signal intensity on MR. None of these patients had a history of trauma. CONCLUSION: Giant intracranial aneurysms can cause significant skull base erosion and extend into the paranasal sinuses, parapharyngeal space, and infratemporal fossa. The CT and MR findings can lead to an accurate diagnosis.

Aged↗