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V Sehgal

Publications and source records attributed to V Sehgal.

13 recordsLinked to original sources
PubMed2001

Intraosseous sacral myxopapillary ependymoma and the differential diagnosis of sacral tumors.

Although involvement of other regions of the spinal cord and brain stem is seen, myxopapillary ependymoma is most commonly found at the filum terminale or cauda equina. Less commonly, myxopapillary ependymoma may occur outside the central nervous system from direct metastatic extension of an intrathecal tumor, and rarely it may present as a primary tumor outside the thecal sac. The authors present a case of primary sacral myxopapillary ependymoma, which was first diagnosed as a chordoma. They then discuss the magnetic resonance imaging findings of this and other sacral tumors. Myxopapillary ependymoma should be considered in the differential diagnosis for a primary expansile sacral mass along with other lesions such as chordoma, aneurysmal bone cyst, and giant cell tumor.

Adult↗
PubMed2001

Dosimetric effect of source centering and residual plaque for beta-emitting catheter based intravascular brachytherapy sources.

Catheter-based radiation delivery systems employing both beta-particle and gamma-ray emitters are currently being investigated for their efficacy in addressing restenosis following percutaneous coronary intervention (PCI). The dosimetric consequences of source centering within the arterial lumen and presence of residual plaque are potentially important issues for the uniform delivery of dose to the arterial tissue. In this study, we have examined the effect of source centering on the resulting dose to the arterial wall from clinical intravascular brachytherapy sources containing 32P and 90Sr/Y90. Monte Carlo simulations using the MCNP code were performed for these catheter-based sources with offsets of 0.5 mm and 1 mm from the center of the arterial lumen in homogenous water medium as well as in the presence of residual plaque. Three different positions were modeled and the resulting dose values were analyzed to assess their impact on the resulting dose distribution. The results indicate a variation ranging from -40% to +70% for 32P source and -30% to +50% for 90Sr/90Y at a radial distance of 2 mm from the center of the coronary artery, relative to the dose from a centered source, for a 0.5 mm offset. The variation for a 1 mm offset ranges from -65% to +182% for 32P source and to -50% to +140% for 90Sr/90Y. A concentric residual plaque layer was also modeled so as to assess the combined influence of offset and residual plaque on the dosimetry. Finally the effect of cardiac motion and its potential impact on catheter position and hence the dose distribution is also examined by considering two separate cases of catheter displacement. The results indicate that dose variations range between -28% to +91% when it is assumed that cardiac motion causes catheter movement during coronary lesion irradiation.

Beta Particles↗
PubMed2001

Comparative efficiency of commercial and improvised spacer device in acute bronchial asthma.

OBJECTIVE: To compare the efficacy of a commercial spacer device versus an improvised spacer device in delivering aerosolized beta-2 agonist through metered dose inhaler in an acute exacerbation of bronchial asthma. DESIGN: Randomized controlled trial. SETTING: Urban tertiary care teaching hospital. METHODS: 60 children between 1 to 12 years of age with acute asthma were prospectively enrolled and randomized into two groups. Detailed history, clinical evaluation and appropriate laboratory investigations were recorded on a pretested proforma. One group received inhaled salbutamol using metered dose inhaler via commercial spacer device (Group 1), while the other received it via improvised spacer device (Group II). The response was sequentially assessed after 20, 40 and 60 minutes of institution of therapy. RESULTS: The two groups were comparable with respect to various parameters at presentation (p > 0.05). All the outcome parameters showed a significant improvement with time in both groups (p < 0.05). There was no statistical difference between the response in the two groups (p< 0.05). CONCLUSION: Metered dose inhaler with improvised spacer device is equivalent in efficacy and a more cost effective alternative to metered dose inhaler with commercial spacer for administration of beta-2 agonist in acute asthma.

Administration, Inhalation↗
PubMed2000

Use of three-dimensional spiral computed tomography imaging for staging and surgical planning of head and neck cancer.

We compare four different three-dimensional (3D) reconstruction methods of spiral computed tomography (CT) data for head and neck cancer to establish the method best suited for specific uses, eg, staging of lymph nodes and viewing of spatial relationships between the tumor, fascial spaces, adjacent soft tissues, and others structures. We evaluated a series of 10 patients (six men and four women), aged 32 to 60 years. Of these, five were histologically diagnosed with squamous cell carcinoma, two with lymphoma, one with thyroid cancer, one with Kikuchi's disease or necrotizing lymphadenitis, and one with esthesioneuroblastoma. All scans were obtained using high-resolution spiral CT (General Electric Medical Systems, Milwaukee, WI). The collimations used were 3 mm and 5 mm, matrix 512 x 512, and reconstruction interval not more than 3 mm. Scanning was performed from the skull base to the aortic arch. Iodinated contrast medium was injected so that the blood vessels were clearly differentiated from nodes. Different techniques of three-dimensional reconstruction were employed, including shaded surface display (SSD), multiplanar reconstructions (MPR), maximum intensity projection (MIP), 3D volume rendering (VR), and combined techniques. The reconstructions were performed in a variety of planes, including sagittal, coronal, and oblique views. In our series of selected patients, the technique of 3D VR showed potential advantages over other techniques. The MIP technique was useful in analyzing the patency of vessels and to exclude thrombus, compression, or displacement by tumor. The use of combined techniques such as SSD and MPR, accurately demonstrated the levels of lymph nodes and the relationship between the tumor projection of interest and various anatomic structures. In conclusion, 3D reconstruction of CT data is useful in the localization and staging of neck tumors and assists in surgical planning and radiation treatment.

Adult↗
PubMed1999

Clinically aggressive diffuse capillary telangiectasia of the brain stem: a clinical radiologic-pathologic case study.

Capillary malformations or telangiectasias of the brain usually exhibit a benign clinical course, although occassionally they may be associated with mild to moderate symptomatology of uncertain origin. We report a case of an exceptionally aggressive capillary telangiectasia in a child, which was associated with progressive neurologic deterioration resulting in death.

Capillaries↗
PubMed1997

Cyclosporine-associated end-stage nephropathy after cardiac transplantation: incidence and progression.

BACKGROUND: The salutary immunosuppressive effects of cyclosporine in extending cardiac allograft survival may be curtailed by its nephrotoxic effects. We reviewed our first 9 years of experience with cyclosporine after cardiac transplantation, to evaluate the incidence and progression of cyclosporine-associated end-stage renal failure necessitating chronic hemodialysis. METHODS: Retrospective computer-based file review and personal interview when possible. RESULTS: The population at risk was comprised of all adult cardiac recipients surviving at least 3 years (n=293). Of these, 19 (6.5%) developed end-stage renal failure requiring chronic hemodialysis. There were 17 men and 2 women (mean age of 45 +/- 11 years). The mean creatinine clearance for the study group decreased by 38% (P<0.001 vs. before transplant) by 6 months after transplantation and by 48% by 3 years postoperatively (P<0.001 vs. before transplant). The mean serum creatinine rose by 80% (P< 0.001 vs. before transplant) by 6 months after transplantation and by 125% by 3 years postoperatively (P<0.001 vs. before transplant). Time elapsed from transplantation to hemodialysis ranged from 3.7 to 9.5 years (mean 6.4 +/- 2). Actuarial 1- year survival after onset of hemodialysis was 75%. CONCLUSIONS: Although cyclosporine remains the central immunosuppressive agent for cardiac allograft recipients, its use leads to a greater than one-third decrease in creatinine clearance by 6 months after transplantation and progression to end-stage renal failure, requiring hemodialysis in 6.5% of cardiac transplant recipients. Moreover, these patients are at increased risk of death compared with other cardiac allograft recipients. This data warrants the search of alternative or adjunctive agents that would allow decreased dosing or reduced nephrotoxicity of cyclosporine, while maintaining equivalent survival.

Adult↗
PubMed1997

Predictors of mortality in subjects hospitalized with acute lower respiratory tract infections.

OBJECTIVE: To identify the predictors of mortality due to acute lower respiratory tract infection (ALRI). DESIGN: Prospective cohort study. SETTING: Urban tertiary care teaching hospital. METHODS: 201 cases with ALRI between 2 weeks to 5 years of age were prospectively enrolled and followed up to determine outcome. Detailed history and clinical evaluation were recorded on a pretested proforma. Significant independent predictors of mortality were determined by comparison of dead subjects (n = 21) with surviving children (n = 180) in a multiple logistic analytic framework. RESULTS: The case fatality rate (CFR) was 10.45%. Significant independent predictors of mortality were (OR, 95% CI) age less than 1 year (23.1, 2.7-197.5), inability to feed (6.2, 1.3-30.7), associated loose stools (5.1,1.2-27.3), weight for age Z score < -3 (3.9,1.01-9.7), short duration of fever (1.2,1.0-1.5) and bandemia (1.1,1.05-1.2). The WHO guidelines identified 91% of children diagnosed as ALRI by clinical and investigative criteria. The CFR was related to severity of WHO classification ("pneumonia"-0%, "severe pneumonia"-8.7% and "very severe pneumonia"-47.0%). However, 2 of the 18 subjects with a diagnosis of "no pneumonia" expired (CFR 11.1% and 10% of total mortality). CONCLUSION: Even in settings of high case fatality, predictors of mortality can be identified in under five children suffering from ALRI. In this context, age below 1 year, inability to feed, presence of loose stools and severe malnutrition merit attention for interventional purposes.

Age Distribution↗
PubMed1996

Cutis laxa.

Explore the source record for details and available documents.

Cutis Laxa↗
PubMed1995

Progressive renal insufficiency following cardiac transplantation: cyclosporine, lipids, and hypertension.

The increasing success of cardiac transplantation has been attributed to the availability of potent immunosuppressive agents, including cyclosporine. With improved graft and patient survival, the incidence of chronic renal insufficiency has increased. We reviewed the medical records of patients who had undergone orthotopic cardiac transplantation and had been followed for at least 3 years posttransplantation to determine the risk factors at initial evaluation and in the early posttransplantation period for subsequent renal insufficiency. We followed 80 adult patients over a mean period of 4.7 years: 39 patients had a serum creatinine > or = 2.4 mg/dL at last follow-up (renal insufficiency or RI group); 41 patients had a serum creatinine < or = 1.7 mg/dL at last follow-up (controls). RI patients tended to be older and had a lower mean glomerular filtration rate (GFR) at initial evaluation. There were no differences in race, gender, or previous history of hypertension between the two groups. Although both groups experienced an improvement in GFR at transplantation and a subsequent decline in GFR by 6 months posttransplantation, the RI group achieved a lower peak GFR at transplantation and a far lower mean GFR at the 6-month analysis. Only the RI group showed a continued decline in GFR. The RI group had more severe hypertension and required a significantly greater number of antihypertensive medications. The RI group had a higher mean total cholesterol at 6 months, but this difference was not sustained. They also had higher triglyceride levels and lower high-density lipoprotein (HDL) levels; there was no difference in low-density lipoprotein (LDL) levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Naturally occurring anti-native DNA antibodies in SLE binding Z-DNA.

A high degree of specificity of circulating anti-DNA antibody for double stranded DNA in the sera of SLE patients was found, as compared to single stranded polymer. The antibody recognized brominated DNA, a polymer that appears to attain Z-conformation as indicated on the basis of UV absorption characteristics. The existence in native DNA of regions undergoing B----Z transition has been detected.

Antibody Specificity↗
PubMedDate not supplied

Automatic bone segmentation technique for CT angiographic studies.

PURPOSE: The purpose of this work was to develop and evaluate an automatic bone segmentation technique for CT angiographic studies. METHOD: An automatic bone segmentation scheme was developed and applied to 40 CT examinations. The results of the segmentation were evaluated subjectively by two radiologists. RESULTS: The bone segmentation was, on average, rated between excellent and good. Automatic segmentation required approximately 25 s/case. CONCLUSION: With this high quality technique, bone can be segmented easily and accurately and subsequently can be removed from CT data sets for further 3D visualization and analysis of various organs.

Angiography↗