Search PubMed⌕ Search

Biomedical subjects

M Sundaram

Publications and source records attributed to M Sundaram.

At least 217 records · Page 12Linked to original sources
PubMed1987

Vertebral erosions in patients undergoing maintenance hemodialysis for chronic renal failure.

Unlike articular erosions in the appendicular skeleton, the frequency, appearance, and clinical relevance of vertebral erosions in azotemic osteodystrophy are not known. Lateral vertebral radiographs of 118 patients on maintenance hemodialysis were reviewed to assess the frequency, distribution, and rate of progression of vertebral erosions. Thirty (25%) of 118 patients showed a superficial corner erosion resembling the so-called Romanus lesion of ankylosing spondylitis. Their presence, whether at a single level or at multiple levels, did not correlate with erosive changes in the phalanges or sacroiliac joints that are known to occur in renal osteodystrophy. Vertebral erosions may progress slowly with time, but seem to have limited bearing on clinical symptoms. In two patients, however, the radiographic changes progressed dramatically, simulating an infection. Biopsy and surgical intervention were considered but not carried out because one patient declined and in the other an infected graft was identified as the source of infection. Both patients had negative scintiscans, and their subsequent clinical courses excluded infectious spondylitis. Vertebral erosions in patients on maintenance hemodialysis are frequent, and there appears to be a spectrum of changes from superficial erosions to large resorptive defects. Further diagnostic evaluation of these erosive changes appears to be warranted only rarely.

Adult↗
PubMed1986

Magnetic resonance imaging of lesions of synovial origin.

Three patients with histologically differing lesions of synovial origin and two with synovial cysts, one of which was a dissecting popliteal cyst, were examined by magnetic resonance imaging (MR) and computerized tomography (CT). The three histologically proven synovial lesions were synovial sarcoma, diffuse giant cell tumor of tendon sheath, and synovial chondromatosis. In two of the five patients MR provided better anatomic and morphologic appreciation than CT, while in the others they were of equal value. CT demonstrated calcification in two of the lesions while on MR calcification could be identified in only one patient where it outlined the mass. MR did not demonstrate calcification in the substance of the diffuse giant cell tumor of tendon sheath. Coronal, transverse, and sagittal images of magnetic resonance graphically demonstrated the extent of the soft tissue masses and their relationship to bone, vessels, and soft tissue structures. Synovial sarcoma had a shorter T1 than diffuse giant cell tumor of tendon sheath (these two lesions being of comparable size) and also had a uniformly longer T2. The dissecting popliteal cyst showed the most intense signals on the T1 weighted images, while the uncomplicated synovial cyst showed a long T1. On the T2 weighted images, each type of cyst showed a long T2. The variance and overlap of intensity of MR signals suggest limited specificity in predicting the histologic nature of the synovial lesion.

Adult↗
PubMed1986

Positron emission tomography in Alzheimer's disease.

Twenty-one patients with a clinical diagnosis of dementia of the Alzheimer's type (DAT) and 29 healthy, age-matched controls were studied using positron emission tomography (PET) and [18F]2-fluoro-2-deoxy-D-glucose to measure regional cerebral glucose consumption in the resting state. Reductions in ratio measures of relative metabolism in some parietal, temporal, and frontal regions were found in mild, moderate, and severe DAT groups. A significant increase in right/left metabolic asymmetry, particularly in parietal regions, also was seen in mild and moderate groups. Only in the severely demented patients was the absolute cerebral metabolic rate reduced significantly from control values. Fourteen patients had repeated PET studies, but only those patients with moderate to severe dementia showed a decline in IQ over 6 to 15 months. There were no significant changes in metabolic measures over time. PET is useful in quantifying regional cerebral dysfunction in DAT, even in the early stages of the disease.

Aged↗
PubMed1986

Pyoderma gangrenosum and erosive peripheral arthritis.

We describe two patients with biopsy-proven pyoderma gangrenosum who developed a peripheral erosive arthritis resembling that seen in psoriatic arthritis. This association is discussed with particular reference to reactive arthritis.

Arthritis↗
PubMed1986

Magnetic resonance imaging in planning limb-salvage surgery for primary malignant tumors of bone.

In defining the linear extent of a malignant tumor in a long bone, radiographs, computerized tomography, and scintigraphy are routinely employed, especially when non-ablative surgery is being considered. The drawbacks of these modalities in defining the true intracompartmental extent of disease within a bone can largely be overcome with the use of magnetic resonance imaging. We did a prospective analysis of magnetic resonance imaging in sixteen consecutive patients with a primary malignant tumor of a long bone, and it showed that this modality has clinical promise of being more precise than the other modalities in defining the true proximal and distal extent of a tumor in a long bone. Coronal images permit easier planning of surgical techniques for salvage of a limb using an allograft than do a multiplicity of transverse images.

Bone Neoplasms↗
PubMed1985

Clinical history, brain metabolism, and neuropsychological function in Alzheimer's disease.

Data concerning 7 patients with a diagnosis of presumptive Alzheimer's disease (mean age, 65.6 years) are presented in detail in relation to the patients' regional cerebral metabolic rates for glucose. Rates were measured by positron emission tomography with fluorine 18-labeled fluoro-2-deoxy-D-glucose under conditions of reduced visual and auditory stimulation. A relationship was found between severity of dementia and brain metabolism. In patients with mild to moderate Alzheimer's disease, memory and intellectual deficits were evident without major reductions in absolute metabolic rates, while ratios of regional to whole brain metabolism revealed reductions in regions of the parietal lobes. In the late, severe form of the disease, brain metabolic rates were consistently and significantly reduced. The findings suggest that memory and intellectual deficits are reflected in reductions of brain metabolism in some brain regions in mild to moderate forms of Alzheimer's disease and that, in the late, severe form of the disease, reductions occur consistently throughout the brain.

Aged↗
PubMed1985

Computed tomography in the pretreatment assessment of carcinoma of the cervix.

Fifty-nine patients with primary or recurrent carcinoma of the cervix were evaluated by computed tomography as part of their presurgical evaluation. The computed tomography staging results were compared with the surgical staging. Computed tomography staging was accurate in 71% (42 of 59), whereas clinical staging was accurate in 66% (39 of 59). In assessing paraaortic nodes by CT, there were 10 true-positive, 20 true-negative, 1 false-positive, and 2 false-negative results (sensitivity, 83%; specificity, 95%), for an overall accuracy of 91%. For pelvic nodes, there were 10 true-positive, 11 true-negative, 3 false-positive, and 6 false-negative results (sensitivity, 62.5% specificity, 78%), for an overall accuracy of 70%. Excretory urograms and barium enemas provided no information not obtained by computed tomography and are probably unnecessary if computed tomography is used as a routine staging examination. At present, computed tomography should not replace clinical assessment of extent of the disease. Its chief advantage over clinical staging is its ability to detect metastases beyond the true pelvis.

Adenocarcinoma↗