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M J Post

Publications and source records attributed to M J Post.

137 records · Page 8Linked to original sources
PubMedDate not supplied

Sequential cranial MR findings of asymptomatic and neurologically symptomatic HIV+ subjects.

PURPOSE: To compare results of a prospective MR and clinical reevaluation of HIV+ asymptomatic and neurologically symptomatic subjects who had had initially abnormal cranial studies to determine what cranial MR changes occur and how these changes correlate with serial neurologic and neuropsychologic findings. PATIENTS AND METHODS: Thirty-one asymptomatic (n = 20) and neurologically symptomatic (n = 11) subjects seropositive for the human immunodeficiency virus (HIV+) were prospectively reevaluated by cranial magnetic resonance (MR) one to two years following an initially abnormal MR of the brain. RESULTS: All 31 HIV+ subjects with initial abnormal MR had abnormal follow-up scans (showing atrophy and/or white matter lesions). Twenty-seven showed no progression of MR abnormalities (among whom were 18 with minimally abnormal scans who remained asymptomatic with improved or static neuropsychologic performance). Of the four subjects with scan changes (all with clinically suspected HIV encephalopathy), one showed MR, clinical, and neuropsychologic test improvement; the remaining three showed MR (n = 3), neurologic (n = 3), neuropsychologic (n = 1) worsening and autopsy (n = 1) confirmed the presence of HIV-1 containing multinucleated giant cells in the brain. CONCLUSIONS: This study suggests that: 1) Progression of intracranial MR abnormalities due to HIV-1 is seen only in a minority of HIV+ subjects over a 1- to 2-year time period, only in those neurologically symptomatic, and correlates with clinical deterioration. 2) Minor cerebral MR abnormalities seen in HIV+ subjects who remain neurologically asymptomatic do not change over a 1- to 2-year period. 3) Although HIV is known to infect the brain early, it may, nevertheless, not routinely do significant anatomical damage early on in the disease, as based on MR criteria.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Lumbar disk herniation and canal stenosis: value of intraoperative sonography in diagnosis and surgical management.

One-hundred-four patients with preoperative diagnoses of lumbar canal stenosis, disk herniation, or a combination of both were evaluated with intraoperative sonography with the intent of (1) describing the sonographic characteristics of herniated disks and distinguishing these from bulging anuli, epidural fat, scar tissue, and spondylolisthesis; (2) establishing criteria for adequate decompression of canal stenosis; and (3) determining the usefulness of sonography in monitoring disk removal. Disk material demonstrates medium echogenicity, different in its sonographic features from bone, epidural fat, scar tissue, and epidural veins. A sonographic diagnosis of disk herniation was made in 43 cases, 41 of which were confirmed during surgery. Sonography established the presence or absence of disk herniation (confirmed by surgery) in 14 of 19 patients who had equivocal preoperative findings. After routine diskectomy, residual disk material was found in 17 (41%) of 41 patients, which led to further surgery in 16 patients with removal of the additional disk fragments. In 84 patients undergoing decompressive surgery for canal stenosis, sonography detected residual canal compression in 19 (23%), which led to a widened decompression in 15 of these patients. Sonography can differentiate disk material from other normal or abnormal structures in the canal; therefore, sonographic monitoring helps to ensure adequate bony decompression and complete diskectomy. We conclude that intraoperative sonography is an important tool in the surgical management of lumbar disk disease and stenosis.

Diagnosis, Differential↗
PubMedDate not supplied

Acquired spinal subarachnoid cysts: evaluation with MR, CT myelography, and intraoperative sonography.

Fifteen patients with acquired spinal subarachnoid cysts (14 surgically proved, one presumed) were evaluated preoperatively with immediate and/or delayed CT myelography (seven patients), MR (11 patients), or both (three patients). CT myelography separated subarachnoid cyst from myelomalacia and/or intramedullary cysts in four cases but failed to diagnose them in three, while MR accurately diagnosed subarachnoid cyst in all 10 cases that were also surgically proved. The results of these preoperative examinations were evaluated to determine the efficacy of each study in diagnosing subarachnoid cysts, ascertaining their extent and internal architecture, and detecting associated abnormalities of the spinal cord. In addition, during surgery these cysts were studied with sonography to gain an understanding of the pathophysiological mechanisms involved in their formation and propagation and to guide the surgeon in their decompression. On the basis of our experience, MR appears to be the most efficient preoperative study in diagnosing and characterizing acquired subarachnoid cyst and associated abnormalities. Intraoperative sonography provides a reliable means of ensuring adequate decompression of these cysts.

Adult↗
PubMedDate not supplied

Radiologic evaluation of spinal cord fissures.

The clinical course and radiographic studies were reviewed of eight patients with posttraumatic spinal cord fissures (rents in the spinal cord communicating with the subarachnoid space). Five patients had spinal cord fissures associated with symptomatic intramedullary cysts that required shunting to alleviate progressive neurologic deficits and intractable pain. Their metrizamide myelograms showed contrast medium passing immediately from the subarachnoid sac into the spinal cord and their immediate metrizamide CT scans delineated the entire extent of the secondary cord cysts. Intraoperative sonography confirmed the presence of the cord fissures with sizeable cysts, detected adhesions, and guided myelotomies and the subsequent shunting and collapse of the cysts. Since neurologic improvement followed the shunting procedures in all five patients treated for progressive symptoms, it was concluded that early radiologic evaluation of posttraumatic spinal cord fissures with symptomatic cord cysts is crucial in the clinical management of these patients.

Adult↗
PubMedDate not supplied

Department of Ophthalmology, University of Alabama, School of Medicine, Birmingham.

Evaluation of over 255 patients with sellar and parasellar lesions allowed study of the computed tomographic (CT) appearance of the cavernous sinus. Optimal visualization of the cavernous sinus was obtained with continuous contrast enhancement of both axial and coronal tomograms. The coronal projection provided imaging of cranial nerves with the cavernous sinus. The intracavernous carotid artery was seen only if it were calcified or encased by tumor extending into or invading the sinus. CT criteria suggesting an abnormal cavernous sinus are: (1) asymmetry of size, (2) asymmetry of shape, particularly the lateral wall, and (3) focal areas of abnormal density within the sinus. The neurovascular anatomy of the cavernous sinus is reviewed and correlated with CT findings. Discrepancies between anatomic and CT appearance are discussed.

Aged↗
PubMedDate not supplied

Central nervous system tuberculosis in HIV-infected patients: clinical and radiographic findings.

PURPOSE: To characterize the radiographic findings on neuroimaging of 25 human immunodeficiency virus (HIV)-seropositive patients with proved central nervous system tuberculosis and to correlate those findings with clinical data. METHODS: Twenty-five HIV-seropositive patients with central nervous system tuberculosis were identified, and their imaging studies (CT and, in some cases, MR) and medical records were reviewed. The diagnosis of central nervous system tuberculosis was based on cerebrospinal fluid culture (n = 20), biopsy (n = 4), and/or autopsy (n = 5), with a clinical diagnosis of central nervous system tuberculosis in one additional patient. Results also were correlated with CD4 counts and chest x-ray findings. RESULTS: Nine (36%) of 25 patients demonstrated meningeal enhancement. Eleven (44%) of 25 demonstrated enhancing parenchymal lesions; 6 patients had tuberculomata, and 5 had tuberculous abscesses. Communicating hydrocephalus was present in 8 (32%) of 25, and infarction was seen in 9 (36%) of 25. Fifteen of 23 chest x-rays were suggestive of pulmonary tuberculosis. Mean CD4 count was 162. Nine (38%) of 24 patients had a history of pulmonary tuberculosis, and 5 (21%) of 24 had no history of tuberculosis or any other opportunistic infection. Overall mortality was 79%. CONCLUSION: Central nervous system tuberculosis has a very high mortality among HIV-infected patients. Because cerebrospinal fluid cultures can take 6 to 8 weeks, the neuroradiologist can play a critical role in patient treatment by suggesting the correct diagnosis based on characteristic imaging findings. Radiographic clues include multiloculated abscess, cisternal enhancement, basal ganglia infarction, and communicating hydrocephalus, which are not findings associated with the more commonly encountered central nervous system lymphoma or toxoplasma encephalitis. Central nervous system tuberculosis may be the initial presentation of acquired immunodeficiency syndrome. In patients with suspected central nervous system tuberculosis, chest x-ray may provide additional support for the diagnosis of tuberculosis.

AIDS-Related Opportunistic Infections↗