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Narinder S Paul

Publications and source records attributed to Narinder S Paul.

8 recordsLinked to original sources
PubMed2006

Radiology of severe acute respiratory syndrome (SARS): the emerging pathologic-radiologic correlates of an emerging disease.

Severe acute respiratory distress syndrome (SARS) caused by SARS-associated coronavirus (SARS-CoV) is a systemic infection that clinically manifests as progressive pneumonia. During the initial phases of infection the virus causes pauci-inflammatory alveolar and interstitial edema that result in imaging abnormalities dominated by ground glass opacities (GGO). Severe SARS cases can develop radiologic and pathologic findings of diffuse alveolar damage. Although radiologic evidence of acute bronchiolitis is absent, SARS-CoV also infects ciliated airway epithelium, probably accounting for respiratory transmissibility of the virus. Radiologic recovery from SARS can be complete, but computed tomography images often show persistent GGO and reticular opacities, some of which reflect pathologic findings of fibrosis. Long-term follow-up imaging of survivors shows gradual decrease of GGO and reticulation with persistent air trapping in some patients. The latter is evidence of small airway disease that is not radiologically evident at the onset of the disease.

Communicable Diseases, Emerging↗
PubMed2005

True versus false left ventricular aneurysm: differentiation with MR imaging--initial experience.

PURPOSE: To assess the usefulness of cardiac magnetic resonance (MR) imaging for differentiation of true from false left ventricular aneurysm in patients after myocardial infarction. MATERIALS AND METHODS: Cardiac MR images obtained in 22 sequential patients (20 men, two women; mean age, 63 years; age range, 45-75 years) with pathologically proved left ventricular true aneurysm (n = 18) or false aneurysm (n = 4) after myocardial infarction were retrospectively analyzed. The MR imaging protocol included steady-state cine imaging followed by perfusion measurement and delayed contrast-enhanced imaging with delays of 15 and 20 minutes. Differences between true and false aneurysms with regard to maximal internal width of orifice, maximal parallel internal diameter, ratio of maximal orifice to maximal internal diameter, presence of mural thrombus and delayed enhancement of pericardium, left ventricular end-diastolic volume, and left ventricular ejection fraction were analyzed by using the Mann-Whitney U test or Fisher exact test, as appropriate. RESULTS: Inferior wall location was noted in two of four patients with false aneurysm and in none of 18 patients with true aneurysm (P = .03). The remaining aneurysms were apicoanterior (two false, 10 true) or apical (eight true). False aneurysms had a ratio of maximal internal width of the orifice to maximal parallel internal diameter that was significantly lower than that of true aneurysms (0.73 vs 1.00, P < .001) and had a significantly higher left ventricular end-diastolic volume (median, 202 vs 136 mL/m(2); P = .001), as well as a nonsignificant tendency toward lower left ventricular ejection fraction (17% vs 28%, P = .15). Mural thrombus was identified in all four patients with false aneurysm and in seven of 18 patients with true aneurysm (P = .09). Delayed enhancement of pericardium was noted in all four patients with false aneurysm and in three of 18 patients with true aneurysm. Resultant sensitivity of MR imaging for the detection of false left ventricular aneurysm was four of four, specificity was 15 of 18, accuracy was 19 of 22, and positive and negative predictive values were four of seven and 15 of 15 patients, respectively. CONCLUSION: Initial experience with a small number of patients suggests that marked delayed enhancement of the pericardium is a characteristic feature of false aneurysm. Study with a larger patient sample is required to further assess this feature.

Aged↗
PubMed2004

Bronchiolitis obliterans syndrome in lung transplant recipients: can thin-section CT findings predict disease before its clinical appearance?

PURPOSE: To determine whether there are thin-section computed tomographic (CT) features that predict bronchiolitis obliterans syndrome (BOS) in lung transplant recipients before the clinical appearance and during the early stages of the disease. MATERIALS AND METHODS: Two hundred ninety-eight thin-section CT scans obtained in 26 lung transplant recipients who did (study group) and 26 lung transplant recipients who did not (control group) develop BOS were reviewed for the presence of mosaic perfusion, bronchiectasis, bronchial wall thickening, and air trapping. BOS was defined by using the recently revised definition of the International Society for Heart and Lung Transplantation. CT scans obtained in the BOS group were divided into three groups: Group A consisted of the last scans obtained before the clinical appearance of BOS; groups B and C consisted of, respectively, the first and last scans obtained after the clinical appearance of BOS. Scans obtained in the control group were acquired during similar posttransplantation periods and matched to scans in each BOS group. Sensitivity, specificity, and positive and negative predictive values were calculated separately for each subgroup. The optimal threshold for each thin-section CT-depicted abnormality was defined by using receiver operating characteristics analysis. RESULTS: The sensitivities of air trapping for the diagnosis of BOS during the periods in which the scans in groups A, B, and C were obtained were 50%, 44%, and 64%, respectively; specificities were 80%, 100%, and 80% respectively. Sensitivities of mosaic perfusion were 4%, 20%, and 36%, respectively; specificities were 100%, 96%, and 96%, respectively. Sensitivities of bronchiectasis were 25%, 24%, and 32%, respectively; specificities were 80%, 80%, and 96%, respectively. Sensitivities of bronchial wall thickening were 4%, 24%, and 40%, respectively; specificities were 96%, 84%, and 80%, respectively. Air trapping was seen intermittently in nine (43%) of 21 patients with CT scans that depicted this finding at least once. CONCLUSION: The value of the finding of air trapping before the clinical appearance and during the early stages of BOS is lower than has been previously reported. When using the recently revised criteria for BOS, the role of thin-section CT as a screening test to evaluate patients with lung transplants appears to be limited.

Adolescent↗
PubMed2004

Prognostic significance of the radiographic pattern of disease in patients with severe acute respiratory syndrome.

OBJECTIVE: This study was performed to evaluate the prognostic significance of the radiographic pattern of disease in probable cases of severe acute respiratory syndrome (SARS). MATERIALS AND METHODS: A retrospective review of 439 radiographs was performed for 51 patients with a final diagnosis of probable SARS. Forty-nine patients were followed up for a mean interval of 23 days (range, 2-63 days). RESULTS: Abnormal findings on a chest radiograph were noted at presentation in 80.4% (41/51) of patients. Four radiographic patterns were seen: normal (group 1) in 19.6% (10/51), focal opacity (group 2) in 39.2% (20/51), multifocal opacities (group 3) in 27.5% (14/51), and diffuse air-space opacification (group 4) in 13.7% (7/51). Radiographic progression of disease occurred in 38.8% (19/49) of the patients in groups 1-4. There were no deaths in groups 1 and 2. In group 3, one (7.7%) of the 13 patients died. Five (71.4%) of the seven patients in group 4 died. Overall, 12.2% (6/49) of the patients died, all of whom had diffuse air-space opacification on the last chest radiograph. In these patients, medical comorbidity was present in 66.7% (4/6), and the exposure history was known in 83.3% (5/6). Death occurred at a mean interval of 18.2 days (range, 9-36 days) from the initial exposure. CONCLUSION: Patients presenting with normal findings or focal air-space opacity on chest radiographs had a good clinical outcome. Patients with multifocal opacities that progressed to diffuse air-space opacification and patients presenting with diffuse air-space opacification had a high fatality rate, but patients in this group were also older and more likely to have comorbid conditions. Patients with SARS present with recognizable patterns of disease that have prognostic significance.

Adult↗
PubMed2003

Prevalence of "silent" pulmonary emboli in adults after the Fontan operation.

OBJECTIVES: The study was done to determine the prevalence of pulmonary emboli (PE) in asymptomatic adult Fontan patients and to identify the risk factors associated with PE. BACKGROUND: Right atrial thrombi and systemic thromboembolic complications have been reported after the Fontan procedure. However, the frequency of silent PE in this patient population is not known. METHODS: All consecutive adult Fontan patients attending the adult congenital clinic over a six-month period underwent ventilation-perfusion (VQ) scanning and blood testing for thrombophilia tendency. If the VQ scan showed an intermediate or high probability for PE, a computerized tomography (CT) pulmonary angiogram was performed to confirm the presence of PE. RESULTS: Thirty patients (mean age 26 +/- 7 years, 57% men) were included in this study. Five (17%) adult Fontan patients had an intermediate or high probability for PE on VQ scan, all of which were confirmed on CT pulmonary angiography. No patient had a thrombophilia tendency. Pulmonary emboli were not present in any patients (30%) taking warfarin. Late age at time of Fontan operation (19 +/- 6 years vs. 11 +/- 6 years, p = 0.012) and type of Fontan anatomy (p = 0.001) were associated with increased risk of silent PE. CONCLUSIONS: Seventeen percent of adult patients with Fontan procedure have clinically silent PE. The long-term hemodynamic implications of this with respect to Fontan attrition over time are unknown. Large randomized prospective studies looking at anticoagulation therapy in all Fontan patients are urgently needed.

Adolescent↗
PubMed2003

Fibrosis of the upper lobes: a newly identified late-onset complication after lung transplantation?

OBJECTIVE: The objective of this study was to describe the high-resolution CT findings of a previously unreported rare complication observed in seven patients who had undergone lung transplantation. CONCLUSION: High-resolution CT findings suggestive of gradual progressive lung fibrosis, predominantly in the upper lobes with relative sparing of the basal segments, may represent a specific and rare type of rejection of still unknown cause in lung transplant recipients.

Adolescent↗
PubMedDate not supplied

Radiologic pattern of disease in patients with severe acute respiratory syndrome: the Toronto experience.

Severe acute respiratory syndrome (SARS) is a transmissible febrile respiratory illness caused by a recently discovered coronavirus. Various patterns of disease progression may be observed that have different implications for the prognosis in those affected by SARS. The appearance of the lungs on chest radiographs of patients with this condition may be normal or may include focal airspace opacity or multifocal or diffuse opacities. Thoracic computed tomography (CT) is more sensitive in depicting SARS than is conventional chest radiography, and CT images obtained in patients with normal chest radiographs may show extensive disease and airspace consolidation. However, because the radiologic appearance of SARS is not distinct from that of other diseases that cause lower respiratory tract infection, early identification of SARS will depend in part on the prompt recognition of clusters of cases of febrile respiratory tract illness. To aid in the differential diagnosis and management of SARS, radiologists must be familiar with the typical clinical and histopathologic findings, as well as the radiologic features of the disease.

Adult↗