PubMed Health⌕ Search

Biomedical subjects

J T Latack

Publications and source records attributed to J T Latack.

At least 19 recordsLinked to original sources
PubMed1986

Magnetic resonance imaging of temporal bone and cerebellopontine angle lesions.

Lesions of the temporal bone and cerebellopontine angle present a diagnostic challenge because of the complex anatomy, multiplicity of lesions, and difficulty in imaging the dense bone of this area. Magnetic resonance imaging, a new, nonionizing imaging modality, dependent on monitoring a radiofrequency signal emitted by excited nuclei in an external magnetic field, has shown promise in imaging of the temporal bone and posterior fossa.

Adult↗
PubMed1986

Patients with partial seizures: evaluation by MR, CT, and PET imaging.

Fifty patients who experienced partial seizures were imaged with computed tomography (CT) and magnetic resonance imaging (MR); 14 of these also had imaging studies of local cerebral glucose metabolism with positron emission tomography (PET). Thirteen patients with attenuation abnormalities on CT scans also had abnormal signals on MR images; ten other patients had MR-image signal abnormalities but normal CT scans. In all seven patients undergoing PET who had MR-signal and sometimes also CT-attenuation abnormalities, areas of metabolic asymmetry were present. Positive PET scans were also seen in three patients with no evidence of abnormality on CT and MR studies. Focal cerebral substance loss on CT and MR studies, present in 21 patients, did not correlate well with electroencephalographic findings. MR is utilized as the initial imaging procedure in patients with partial seizures because it is more readily available and less invasive than PET and more sensitive than CT scanning.

Adolescent↗
PubMed1986

Magnetic resonance imaging of the head and neck.

Magnetic resonance imaging (MR) has already gained wide acceptance in the evaluation of intracranial and spinal canal abnormalities. MR also provides excellent resolution of certain tumors of the head and neck and is particularly useful for the evaluation of neoplasms in the vicinity of the skull base. The absence of a bone signal prevents the streaking artifact so troublesome with computerized axial tomography (CT) and allows better definition of tumor. MR does not use ionizing radiation and appears to be an innocuous imaging mode--thus multiple examinations in young patients are not objectionable with MR. The ability to obtain images in multiple planes by control of the magnetic gradients allows for axial, sagittal, and coronal imaging, without changing the supine position of the patient. Multiple projections are helpful in providing better preoperative assessment of the extent and size of certain neoplasms of the neck.

Brain↗
PubMed1986

Preoperative evaluation and surgical management of the Arnold-Chiari II malformation.

The authors report their recent experience with 14 meningomyelocele patients with the Arnold-Chiari II malformation. Three major types of fourth ventricle anomalies seen in the Arnold-Chiari II malformation are defined, based on preoperative magnetic resonance imaging and intraoperative ultrasound studies. The Type A deformity is defined as no cystic dilatation of the fourth ventricle. In the Type B anomaly, there is intracranial dilatation of the fourth ventricle. The Type C deformity involves intraspinal dilatation of the fourth ventricle, either dorsal to the cord or within the substance of the cord. The Type A deformity was most common in infants, and in two cases progression from a Type A to Type B deformity was documented. Recognition of the type of Arnold-Chiari II malformation aids in designing an operative approach more specific to that structural abnormality. Intraoperative ultrasound is a valuable adjunct in localization of the underlying anomalies and permits safe decompression of the fourth ventricle. The authors' indications for surgery now include failure to thrive due to either early respiratory and swallowing dysfunction, progressive spasticity, or upper-extremity weakness. Nine patients significantly improved following surgery and three patients with a progressively deteriorating course were stabilized by surgery. Decompression of the fourth ventricle by fenestration and internal shunting appears to be well tolerated, even in young infants, and is recommended in the treatment of the Arnold-Chiari II deformity.

Adolescent↗
PubMed1985

The initial diagnosis of multiple sclerosis: clinical impact of magnetic resonance imaging.

Thirty patients in whom the initial diagnosis of multiple sclerosis was clinically entertained underwent cranial magnetic resonance imaging (MRI) in close temporal relationship to cranial x-ray computed tomography (CT), electrodiagnostic studies (visual evoked responses, brainstem auditory evoked responses, and somatosensory evoked responses), and cerebrospinal fluid analyses (oligoclonal bands, myelin basic protein, and IgG/albumin ratio). In 26 of the 30 patients, MRI demonstrated lesions consistent with multiple sclerosis that corresponded, at least in part, with the clinically expected neuroanatomical lesion distribution. Two of the 4 patients with normal MRI had normal electrodiagnostic studies and cerebrospinal fluid analyses, and the other 2 had a single abnormal or equivocal electrodiagnostic study. All 26 patients with abnormal MRI had at least one other abnormal laboratory test. CT revealed only the largest lesions, and in the patients with abnormal CT, MRI demonstrated even more lesions. MRI, in this limited series, proved to be a strong tool in the initial diagnosis of multiple sclerosis; it may prove to be the single best test, with a sensitivity exceeding that of electrodiagnostic studies and cerebrospinal fluid analysis.

Adolescent↗
PubMed1985

Primary and secondary histiocytic lymphoma of the brain: CT features.

The authors examined 19 patients with diffuse histiocytic lymphoma of the brain, including 8 with primary disease and 11 with secondary disease. Both primary disease and secondary disease involving the brainstem and deep nuclei exhibited the characteristic CT appearance, consisting of a large, solid, homogeneously enhanced mass with varying amounts of edema. However, most secondary lymphomas outside the brainstem and basal ganglia contained large areas of low attenuation consistent with necrosis. Multifocal lesions were seen only in patients with secondary lymphoma. Systemic chemotherapy for extracranial lymphoma had no effect on the CT appearance of intracranial lesions. The authors suggest that these "unusual" CT patterns are actually typical of a distinct subset of histiocytic lymphomas.

Adolescent↗
PubMed1985

Epidermoidomas of the cerebellopontine angle and temporal bone: CT and MR aspects.

Epidermoidomas were found in four locations within and adjacent to the temporal bone: cerebellopontine angle, petrous apex, facial geniculate ganglion region, and tympanic-mastoid cavity. Lesions in each of these locations presented different clinical and imaging characteristics. Cerebellopontine angle epidermoidomas were seen on computed tomography (CT) as low-attenuation masses in the posterior fossa. Petrous apex and geniculate ganglion region lesions destroyed and expanded the bone of their respective regions. Tympanic-mastoid cavity epidermoidomas were relatively nonspecific, soft-tissue masses. CT study of the brain and temporal bone was the single most informative imaging procedure in the preoperative evaluation of these lesions. Magnetic resonance images complemented CT scans for evaluation of the size and extent of the abnormality but were relatively nonspecific and did not allow preoperative differentiation of epidermoidomas from other temporal bone lesions.

Adolescent↗
PubMed1985

Posttraumatic progressive myelopathy. Clinical and radiologic correlation employing MR imaging, delayed CT metrizamide myelography, and intraoperative sonography.

Posttraumatic progressive myelopathy (PTPM) was studied in nine patients and grouped into three categories on the basis of characteristic radiographic findings and response to therapy: (a) myelomalacia with no cystic degeneration, which has poor response to therapy; (b) small cysts, with poor response to therapy; and (c) large cysts, which are effectively treated by decompression. One type dominated in each patient, although a mixture of types was present in each. Magnetic resonance (MR) imaging gave slightly improved resolution and specificity of type, decreased morbidity, and simplification of procedure in comparison with imaging by delayed computed tomographic metrizamide myelography (DCTM). DCTM and MR imaging results correlated nearly equally with those of intraoperative sonography (IOS) and pathologic study at surgery. IOS was superior to DCTM or MR imaging in detecting septations and small additional cysts. IOS also was helpful in myelotomy positioning, shunt placement, and verification of cyst decompression. MR imaging may replace DCTM in the preoperative evaluation of PTPM, followed by IOS imaging as indicated. Patients with nonmyelopathic signs and symptoms (e.g., radiculopathy) probably still require study with conventional and/or CT myelography.

Adolescent↗
PubMed1985

The giant cholesterol cyst of the petrous apex: a distinct clinical entity.

The giant cholesterol cyst (GCC) of the petrous apex may now be considered a distinct clinical entity and should be considered in the differential diagnosis of lesions of the midcranial skull base. This benign cystic lesion of the petrous apex gradually enlarges and may produce progressive bone erosion and serial neurologic deficits of the cranial nerves within the temporal bone and jugular foramen. We report here five instances of this lesion (3 patients with unilateral and 1 patient with bilateral petrous apex lesions) and describe the natural history, diagnostic evaluation, pathology, and surgical management.

Adult↗
PubMed1984

Gas as a mass: a symptomatic spinal canalicular collection.

A symptomatic collection of spinal canalicular gas of degenerative origin was observed by computed tomography. Relief of symptoms followed gas aspiration. The collection involved the lateral recess. Such gas collections do not appear to represent benign, transient entities in all patients.

Gases↗
PubMed1984

Ossification in the cephalic attachment of the ligamentum flavum. An anatomical and CT study.

A review of 50 anatomical specimens and 100 routine CT scans of the chest and abdomen demonstrated that ossification in the cephalic attachment of the ligamentum flavum is a common anatomical finding, but not as common on CT. Examination of hospital charts and plain radiographs of 26 patients with such ossification suggests that it is probably a normal variant; there was no evidence that it is related to diffuse idiopathic skeletal hyperostosis (DISH) or inflammatory arthropathy. Marked ossification may cause or contribute to neurological symptoms.

Adolescent↗
PubMed1984

Real-time sonography during spinal surgery.

Real-time sonography was performed during spinal surgery in eight adult patients with seven different types of lesions. Cervical, thoracic, and lumbar lesions were included. All were examined prior to dural opening, using the saline-filled wound for water-path imaging. Five extramedullary masses and two intramedullary cavities were well delineated, allowing optimal surgical access to be determined at the moment of approach. Sonography also was abnormal in one case of diffuse spinal cord expansion, but no tissue sonographically distinguishable from spinal cord substance could be identified. Adequacy of surgical treatment was evaluated by repeat sonography before dural closure in one case of extramedullary mass and two cases of intramedullary cavities. Sonography is both reliable and beneficial during surgery for a variety of intraspinal lesions.

Adult↗
PubMed1984

Intraoperative sonographic delineation of low-grade brain neoplasms defined poorly by computed tomography.

Sixty-four consecutive primary or metastatic brain tumors were reviewed to assess the efficacy of intraoperative sonography for localization, biopsy, and/or drainage. In 12 cases, preoperative CT data were incomplete or confusing, usually due to low-density, non-enhanced areas in which low-grade tumor could not be reliably differentiated from necrosis, edema, or cyst. In each case, intraoperative sonography clarified the nature of the solid tumor component by its distinct hyperechogenicity, facilitating biopsy. As a guide to surgical biopsy of brain tumors, sonography has some advantages even over stereotactic systems, which depend upon accurate CT definition of the lesion.

Adult↗
PubMed1984

Iohexol versus metrizamide for lumbar myelography: preliminary report of double-blind trial.

Lumbar myelography was performed in 38 patients; 19 received iohexol (an investigational aqueous contrast agent) and 19 received metrizamide. Iohexol is stable in solution, which is not the case with metrizamide. There was no other significant difference in diagnostic utility or quality between the two media. However, there was considerable postmyelography morbidity in the metrizamide group, but no postmyelography morbidity in the iohexol group. Preliminary clinical evidence suggests that iohexol is significantly superior to metrizamide as a contrast agent for lumbar myelography.

Adult↗
PubMed1984

Iohexol versus metrizamide for lumbar myelography: double-blind trial.

Lumbar myelography was performed in 50 patients; 25 received iohexol (an investigational aqueous contrast agent) and 25 received metrizamide. The two media produced radiographs of equal quality. However, iohexol is stable in solution, while metrizamide is not. Further, markedly less morbidity resulted from iohexol. These features indicate that iohexol may be superior to metrizamide as a contrast agent for lumbar myelography.

Adult↗
PubMed1983

Facial nerve neuromas: radiologic evaluation.

Eight patients who had facial nerve neuromas were examined, and the radiographic findings are reported. Thin section tomography, high resolution computed tomography, posterior fossa computed tomography, and cerebellopontine angle cisternography using Pantopaque (iophendylate) demonstrated bone erosions and soft tissue masses conforming to the course of the facial nerve. The lesions generally exhibited either a proximal or a distal pattern of nerve involvement. Radiologic imaging frequently permits a correct preoperative diagnosis and accurate definition of the extent of facial nerve neuromas, assessments that are important for proper patient management.

Adult↗
PubMed1982

Ossification in the caudal attachments of the ligamentum flavum. An anatomic and computed tomographic study.

A review of anatomic specimens and routine computed tomographic (CT) scans of the chest and abdomen demonstrated that ossification in the caudal attachments of the ligamentum flavum is a common anatomic finding, but a much less common CT finding. Its characteristic location should help prevent confusion with other entities. The present study was prompted by a case of thoracic spine trauma, reported here, in which areas of bone density in the spinal canal simulated fracture fragments. The true nature of these bony projections, namely ossification in the ligamentum flavum, was established by computer reconstruction of axial CT images.

Adult↗