Multiple sclerosis characteristics in African American patients in the New York State Multiple Sclerosis Consortium.

The objective of this study was to determine the clinical characteristics of multiple sclerosis (MS) in African American (AA) patients in the New York State Multiple Sclerosis Consortium (NYSMSC) patient registry. The NYSMSC is a group of 18 MS centers throughout New York State organized to prospectively assess clinical characteristics of MS patients. AAs comprise 6% (329) of the total NYSMSC registrants (5602). Demographics, disease course, therapy, and socioeconomic status were compared in AA registrants versus nonAfrican Americans (NAA). There was an increased female preponderance and a significantly younger age at diagnosis in the AA group. AA patients were more likely to have greater disability with increased disease duration. No differences were seen in types of MS and use of disease modifying therapies. Our findings suggest a racial influence in MS. Further genetic studies that consider race differences are warranted to elucidate mechanisms of disease susceptibility.

SPECT and lumbar MRI in back pain with emphasis on changes in end plates in association with disc degeneration.

Over a two-year period, 48 sequential patients were selected because they showed type I or II end plate changes on magnetic resonance imaging (MRI) and/or had positive single-photon emission computerized tomography (SPECT) scan in the area of disc degeneration. They were selected out of a large group of patients who were being evaluated by MRI and SPECT scan for low back pain. In this group of 48 patients, 47 had positive SPECT scans at the disc space, which on MRI indicates degenerative disc disease. Of these, 38 had end plate changes on the MRI, but 10 did not have end plate changes on the MRI even though their SPECT was positive. None of the 48 patients had evidence of other pathology such as fracture, metastatic disease or spondylolysis. The MRI changes were both of type I and type II and thought to represent increased vascularization of the fibrous tissue or fatty replacement of marrow in the area of the end plate. Based on this study, we are proposing that a positive end plate SPECT in degenerative disc disease is related to marrow changes in the region of the end plate of the disc. Also, we are proposing that SPECT may be of value in delineating early end plate changes prior to the MRI showing type I or type II change in the same area.

A molecular mechanics and database analysis of the structural preorganization and activation of the chromophore-containing hexapeptide fragment in green fluorescent protein.

We propose that heterologous posttranslational chromophore formation in green fluorescent protein (GFP) occurs because the chromophore-forming amino acid residues 65SYG67 are preorganized and activated for imidazolinone ring formation. Based on extensive molecular mechanical conformational searching of the precursor hexapeptide fragment (64FSYGVQ69), we suggest that the presence of low energy conformations characterized by short contacts (approximately 3 A) between the carbonyl carbon of Ser65 and the amide nitrogen of Gly67 accounts for the initial step in posttranslational chromophore formation. Database searches showed that the tight turn required to establish the key short contact is a unique structural motif that is rarely found, except in other FSYG tetrapeptide sequences. Additionally, ab initio calculations demonstrated that an arginine side chain can hydrogen bond to the carbonyl oxygen of Ser65, activating this group for nucleophilic attack by the nearby lone pair of the Gly67 amide nitrogen. We propose that GFP chromophore-formation is initiated by a unique combination of conformational and electronic enhancements, identified by computational methods.

SPECT evaluation of lumbar spondylolysis and spondylolisthesis.

Fifty patients with back pain and radiologically diagnosed spondylolysis were evaluated by a single-photon emission computed tomography (SPECT bone scanning). These patients were separated into three groups according to the degree of spondylolisthesis accompanying the spondylolysis. The data obtained from the study indicate that in acute spondylolysis, the SPECT scan is positive at the pars interarticularis. As the spondylolysis becomes chronic, the SPECT scan tends to revert toward normal even though healing of the spondylolysis has not occurred. As spondylolisthesis develops and progresses, the SPECT scan again becomes positive. The positivity, however, is more anterior and more diffuse. The authors propose that SPECT scanning in spondylolysis is not a positive or negative process, but rather varies with the time and stability of the spondylolytic spine.

SPECT evaluation of unilateral spondylolysis.

Three patients with unilateral spondylolysis were evaluated with SPECT and Lumbar CT. All three cases had positive scans. However, the SPECT images were unique to each case. Therefore, the interpretation of the SPECT activity was undertaken in terms of the known natural history of both unilateral and bilateral spondylolysis.

MRI documentation of hemorrhage into post-traumatic subdural hygroma.

Rapid enlargement of a post-traumatic hygroma was demonstrated by MRI in a patient who had sequential studies performed after head injury. The enlargement was shown to be due to hemorrhage into the hygroma.

Bone SPECT in patients with persistent back pain after lumbar spine surgery.

Twenty-five patients with persistent pain after lumbar spine surgery for pain were evaluated by single photon emission computed tomography (SPECT) bone scanning. The patients were divided into three groups, depending on the type of surgery performed. The data obtained indicates that lumbar spine SPECT is most useful in conditions where there is the greatest likelihood of instability. The study shows that the improved contrast and better three-dimensional patient information gained through lumbar spine SPECT permits more accurate delineation of the level of maximum instability and stress on the vertebra.

Nonsurgical management of an isolated interhemispheric subdural hematoma sequentially followed by CT.

Using transaxial CT scan, we diagnosed a patient with head injury as having an isolated interhemispheric subdural hematoma, on the basis of the widening of the superior sagittal sinus. The diagnosis was confirmed by coronal views. The patient was managed nonsurgically and gradual reabsorption of the hematoma was documented by CT. During the latter stages of reabsorption, two parallel lines were noted on the transaxial views as the subdural collection became smaller and drew away from the sagittal sinus. We conclude that an unusual widening of the superior sagittal sinus on transaxial CT scan warrants suspecting an interhemispheric subdural hematoma. Because the hematoma may be obscured by the overlying clot, coronal views may also be valuable.

Multiple meningiomas evaluated by computed tomography.

There were 15 cases of multiple meningiomas in a consecutive series of 168 cases of meningioma studied by computed tomography during the last 5 years. This incidence of 8.9% is significantly higher than the 1 to 3% incidence reported previously. A brief clinical survey of the 15 cases and a description of the location of the meningiomas as demonstrated by computed tomography are presented. The possible cause of the higher incidence and various theories of the etiology of multiple meningiomas are explored.

Reversible autonomic neuropathy and hypertrophic osteoarthropathy in a patient with bronchogenic carcinoma.

We report a case of adenocarcinoma of the lung with pandysautonomia and pulmonary osteoarthropathy. Surgical resection of the tumor followed by radiation therapy for the residual tumor resulted in complete resolution of arthropathy and almost complete recovery from autonomic dysfunction. The symptoms of arthropathy and autonomic neuropathy recurred simultaneously several months later with increase in the tumor mass as confirmed at second surgical exploration. The second thoracotomy revealed an inoperable tumor. Following the second thoracotomy, while the arthropathy was relieved, the autonomic neuropathy persisted. We concluded that autonomic neuropathy is related to the tumor mass, and pulmonary osteoarthropathy and autonomic neuropathy are probably caused by different mechanisms, as yet undefined.

Degenerative disorders of the cerebellum studied by computerized tomography.

A review of our cases as well as of the clinical and radiological literature indicates that, in instances of cerebellar degeneration, certain CT patterns are constant. The most reliable are: 1. Prominence of cerebellar sulci. These are usually not seen normally, except for some of the primary fissures; in atrophy the sulci are easily distinguished. 2. Enlargement of the superior cerebellar cistern and vermian cistern. 3. Enlargement of the cerebellopontine cistern. This cistern, which is also referred to as the cerebellopontine angle cistern and as the lateral recess of the cerebellopontine cisterns, is particularly prominent when the middle cerebellar peduncle is significantly involved. 4. Enlargement of the pre-pontine cistern, which occurs primarily with involvement of the pons. 5. The fourth ventricle may be enlarged, particularly in conditions where the midline cerebellar nuclei are affected. However, the enlargement of the fourth alone does not have to be associated with a pathological process. As previously established with pneumoencephalographic studies, the size of the fourth ventricle can be variable (14). Likewise, enlargement of the cisterna magna is not usually associated with any pathological condition of the cerebellum (15).

Alcoholism and cerebral atrophy: a study of 50 patients with CT scan and psychologic testing.

A study of 50 alcoholic patients was carried out with CT scans of their brains and psychologic testing. These patients were alcohol and drug free, and without neurologic or psychiatric disorders at the time of the examinations. Fifty-eight percent of the patients had cerebral atrophy. There was no correlation between the results of the psychologic testing and cerebral atrophy. The only factor that correlated to a significant degree with cerebral atrophy was the duration of problem drinking. Only the mean duration of problem drinking was statistically significantly longer in the patients with cerebral atrophy compared to those patients with normal CT scans. Implications of this finding of high prevalence of cerebral atrophy in alcoholics is discussed.

Biplane computed tomography of intracranial meningiomas with extracranial extension.

Fifteen of 130 intracranial meningiomas evaluated by biplane computed tomography (CT)--axial transverse and coronal--were found to have direct extracranial extension. These include five pterional meningiomas en plaque with extension to the orbit and temporal fossa; three subfrontal meningiomas invading the paranasal sinuses, nasal cavity, or orbit; three posterior fossa meningiomas with extracranial extension to the neck; three hyperostosing parasagittal meningiomas with extracranial tumors; and one tuberculum sellae meningioma with spread to the optic sheath. Biplane CT is of value in delineating the precise extent of the tumor, both intracranially and extracranially, as well as in evaluating bony changes such as hyperostosis or destruction.