PubMed Health⌕ Search

Biomedical subjects

K P Ravikrishnan

Publications and source records attributed to K P Ravikrishnan.

14 recordsLinked to original sources
PubMed2001

Patterns of abnormal FDG uptake by various histological types of non-small cell lung cancer at initial staging by PET.

The aim of this study was to identify useful patterns of abnormal fluorine-18 fluorodeoxyglucose (FDG) uptake by different types of non-small cell (NSC) lung cancer and to assess their clinical implications. One hundred and three sequential patients with newly diagnosed, pathology-proven NSC lung cancer were included. FDG positron emission tomography (PET) images were acquired using a dedicated PET scanner. There were 35 squamous cell carcinomas (SQC), 17 large cell cancers (LGC), 38 adenocarcinomas (ADC), 1 bronchioloalveolar carcinoma (BAC) and 12 non-classified NSC cancers. PET images were categorized into detectable patterns of necrotic center in the primary tumor, satellite lesions (T4), hilar lymph nodes (N1), and N2, N3, and M1 lesions by visual interpretation of PET images for SQC, LGC, and ADC (n=90; BAC and non-classified NSC cancers were excluded). The PET lesions were correlated with surgical pathology and with CT findings in inoperable cases. Necrosis was more commonly present in the primary tumors of LGC (53%) and SQC (43%) than in those of ADC (26%) (P<0.0001 and <0.01, respectively). The frequencies of nodal uptake in ADC, SQC and LGC were similar (71%, 60%, and 59%, respectively). However, M1 lesions were present significantly more often in LGC (41%) and ADC (34%) than in SQC (3%) (both P<0.0001). Significantly more surgically inoperable cases were found by PET (T4, N3, M1) in ADC (50%) and LGC (41%) than in SQC (26%) (P<0.001 and <0.02, respectively). Our results suggest a wide variation of PET findings for different types of NSC lung cancer. Identification of these patterns is useful in clinical PET interpretation, in that knowledge of the most probable association between the PET patterns and the histological types will facilitate initial staging and planning of management.

Adenocarcinoma↗
PubMed1992

Tuberculosis. How can we halt its resurgence?

Tuberculosis is a well-known disease with classic clinical manifestations. However, a change in host defense mechanisms may cause atypical manifestations. A thorough understanding of presentations of the disease and of the principles of prevention and treatment is important in stopping the spread of tuberculosis.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Routine chest radiographs in exacerbations of chronic obstructive pulmonary disease. Diagnostic value.

Routine admission chest radiographs were abnormal in 35 (14%) of 242 patients hospitalized with an exacerbation of chronic obstructive pulmonary disease and resulted in management changes that were appropriate and clinically significant in only 11 cases (4.5%). Based on our analysis of clinical variables predictive of significant radiographic abnormalities and our assessment of clinically important findings, we propose the following indications for admission chest radiographs in patients with an acute exacerbation of chronic obstructive pulmonary disease: white blood cell count above 15 x 10(9)/L and polymorphonuclear leukocyte count above 8 x 10(9)/L, history of congestive heart failure, history of coronary artery disease, chest pain, or edema. In view of the low yield of clinically significant abnormalities, we believe that routine chest radiographs need not be performed in this patient population. The use of selective criteria could eliminate unnecessary studies while assuring recognition of important new radiographic abnormalities.

Acute Disease↗
PubMed1988

Optimum anesthesia with intrapleural lidocaine during chemical pleurodesis with tetracycline.

Chemical pleurodesis with tetracycline is frequently complicated by pleuritic chest pain. The most promising approach to control pain is to optimize the use of intrapleural lidocaine. While administering amounts of intrapleural lidocaine larger than commonly reported, we attempted to determine a safe and more effective dose, by using a subjective and objective assessment of pain, by measuring serum concentrations of lidocaine, and by observing patients for possible toxic effects of lidocaine. Chemical pleurodesis with tetracycline was performed on ten patients receiving an intrapleural dose of 200 mg of lidocaine (group 1) and on ten patients receiving a 250-mg dose (group 2). A significantly greater number of patients in group 2 were free of pain following pleurodesis (7/10 vs 1/10; p = 0.006). Of the 80 serum lidocaine levels obtained, only one value (6.1 micrograms/ml), in an asymptomatic patient in group 1, exceeded the therapeutic range (1.5 micrograms/ml to 5.5 micrograms/ml). One patient in group 2 experienced transient numbness of the right hand, a possible side effect of lidocaine. We conclude that to achieve optimum anesthesia during chemical pleurodesis with tetracycline, it is necessary to use doses of intrapleural lidocaine large than previously reported. Until the feasibility of a further escalation is demonstrated, 250 mg should be considered the standard dose.

Anesthesia, Local↗
PubMed1980

Tuberculous enteritis and peritonitis. Report of 36 general hospital cases.

We studied 36 patients with gastrointestinal tuberculosis: 21 had peritonitis, 11 had enteritis, and four had both. Diagnostic criteria were (1) caseating granulomas or positive smear or culture from an abdominal specimen; (2) culture-proved pulmonary tuberculosis plus ascitic fluid containing protein, greater than 3.0 g/dL, and more than 50% lymphocytes, or granulomatous enterlitis on x-ray studies that resolved with antituberculous therapy. In only four of 15 patients with enteritis was the disease confined to the ileocecal region. Fourteen patients (40%) had complications: bowel obstruction in ten, perforation in six, and fistula in five. Five of these died. Two perforations and one death followed paracentesis and needle biopsy. Tuberculous peritonitis can be diagnosed without biopsy when lymphocytic exudative ascites responds to antituberculous chemotherapy given for concurrent culture-proved pulmonary tuberculosis. Patients with pulmonary tuberculosis and persistent abdominal complaints who have granulomatous enteritis should be considered to have tuberculous enteritis. Surgery is reserved for bowel obstruction, perforation, fistula, or a mass that does not resolve with drug therapy.

Adult↗
PubMed1980

Endobronchial mass caused by tuberculosis.

We report a case that illustrates an unusual manifestation of tuberculosis with massive atelectasis secondary to an endobronchial polypoid lesion. The rarity of this manifestation, coupled with the nonspecific findings on biopsy, delays recognition and therapy. Tuberculosis should be considered in the differential diagnosis of endobronchial mass lesions in the right clinical setting.

Aged↗
PubMed1979

Gallium-67 citrate scanning--a new adjunct in the detection and follow-up of extrapulmonary tuberculosis: concise communication.

Gallium-67 citrate scans were obtained in 11 patients considered at risk for extrapulmonary tuberculosis. Radiographic and bacteriologic studies were performed routinely and tissue biopsy selectively. Of five patients with proven extrapulmonary tuberculosis, there were three with renal tuberculosis, one with Pott's disease, and one with peritoneal tuberculosis. The Ga-67 scan correctly predicted presence or absence of active extrapulmonary foci in all 11 patients. Follow-up scans correlated well with clinical response to therapy. The diagnosis of extrapulmonary tuberculosis is often overlooked because of nonspecific symptoms and frequent lack of concurrent lung involvement. Scanning with Ga-67 citrate offers a reliable and simple means of screening patients at risk and of monitoring response to treatment.

Gallium Radioisotopes↗
PubMed1977

Pulmonary and articular sporotrichosis.

A 46-year-old man presented with swelling and pain in the right knee and a history of nonproductive cough and weight loss. Sporotrichum schenkii was cultured from synovium, synovial fluid, sputum, and bronchial washings. No other pathogens were cultured. Neither skin lesions nor history of exposure to S. schenckii was present, but 7 years before this admission the patient had been treated for suspected pulmonary tuberculosis despite negative mycobacteriology. The case is believed to represent systemic spread from chronic pulmonary sporotrichosis and supports the hypothesis that the lung may serve as a portal of entry in noncutaneous systemic sporotrichosis.

Humans↗
PubMed1976

Lung carcinoma superimposed on pulmonary tuberculosis.

Review of patients with active pulmonary tuberculosis over a three-year period showed an increased incidence of bronchogenic carcinoma (5%). There had been considerable delay in establishing diagnosis of coexistent carcinoma which was attributed to finding of acid-fast bacilli and relative ease of ascribing all findings to that cause. Suspicious roentgen signs are reviewed and the importance of sputum cytology is also stressed.

Carcinoma, Bronchogenic↗
PubMed1976

Xerotomography of peripheral lung lesions.

Xerotomography was compared to conventional tomography in 72 patients with peripheral lung lesions. The xerotomogram was superior to the conventional tomogram in 41 patients, and yielded no additional information in 31. Details of lesions were better displayed, especially the margins: cavitations, air bronchogram and bronchiectasis, and calcification. Differentiation between benign, inflammatory and malignant lesions was facilitated. The xerotomographic process improved the image detail of lesions due to the edge enhancement property and the greater recording latitude of contrast of the xeroradiographs. Xerotomography is recommended only in selected patients for a few tomographic cuts because of the high radiation dosage.

Adult↗