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K S Naik

Publications and source records attributed to K S Naik.

11 recordsLinked to original sources
PubMed1999

The transrectal ultrasound and MRI appearances of granulomatous prostatitis and its differentiation from carcinoma.

AIMS AND METHODS: Granulomatous prostatitis is a benign inflammatory condition of the prostate which can be mistaken for prostatic carcinoma both clinically and on ultrasound, but is distinguishable histologically. The transrectal ultrasound (TRUS) and magnetic resonance imaging (MRI) appearances of 10 patients with histologically confirmed granulomatous prostatitis were evaluated to try and identify any correlation between the two techniques or any specific features on MRI to help distinguish it from carcinoma. Clinical findings and serum prostatic specific antigen (PSA) levels were also evaluated. RESULTS: In five patients, both TRUS and MRI were concordant, showing only changes of benign prostatic hypertrophy (three patients) or showing no abnormality (two patients). In a further three patients, both TRUS and MRI were abnormal, with appearances suggestive of carcinoma. One of these patients had tuberculous prostatitis and had a past history of tuberculosis. In the remaining two patients, there was a discrepancy between TRUS and MRI findings, carcinoma being suspected on TRUS in one with a normal MRI, and carcinoma suspected on MRI in the other with a normal TRUS. CONCLUSION: There is no pattern of clinical, biochemical, ultrasound or MRI findings that allows a specific diagnosis of granulomatous prostatitis to be made, or differentiation from prostatic carcinoma.

Aged↗
PubMed1999

Hepatic lesion detection: comparison of MR imaging after the administration of superparamagnetic iron oxide with dual-phase CT by using alternative-free response receiver operating characteristic analysis.

PURPOSE: To compare the performance of magnetic resonance (MR) imaging after the administration of superparamagnetic iron oxide (SPIO) and dual-phase computed tomography (CT) in the depiction of liver metastases. MATERIALS AND METHODS: Fifty-one hepatic resection candidates with known colorectal metastases were examined. MR imaging comprised fast spin-echo (SE) T2-weighted imaging, T1-weighted gradient-echo (GRE) fast low-angle shot imaging before SPIO enhancement, dual-echo SE imaging, T2-weighted fast low-angle shot imaging, and T1-weighted GRE imaging after SPIO enhancement. CT was performed with 8-mm collimation and 1:1 pitch; imaging commenced 20 seconds and 65-70 seconds after injection of 150 mL of contrast medium. All images were reviewed independently by four blinded observers. The alternative-free response receiver operating characteristic (ROC) method was used to analyze the results, which were correlated with findings from surgery, intraoperative ultrasonography, and histopathologic studies in 31 patients and with consensus review together with all other imaging and clinical follow-up in 20 patients. Sensitivities were also calculated. RESULTS: The mean sensitivity of MR was significantly higher than that of CT (p < .02): 79.8% for MR and 75.3% for CT for all lesions, and 80.6% for MR and 73.5% for CT for malignant lesions. The mean areas under the alternative-free response ROC curves were 0.83 for MR and 0.78 for CT (difference not significant). CONCLUSION: SPIO-enhanced MR imaging was more sensitive than dual-phase CT in the depiction of colorectal metastases.

Colorectal Neoplasms↗
PubMed1998

Staging lymphoma with CT: comparison of contiguous and alternate 10 mm slice techniques.

PURPOSE: To compare two computed tomography (CT) techniques, contiguous 10 mm and alternate 10 mm slices of the chest, abdomen and pelvis, for initial staging of lymphoma. SUBJECTS AND METHODS: Fifty-two consecutive patients referred at initial diagnosis for lymphoma staging by CT were examined with contiguous 10 mm slices of the chest, abdomen and pelvis. Oral contrast was administered, but no intravenous contrast. Two sets of films for each examination were printed, one with 10 mm contiguous slices and one with 10 mm alternate slices. The two sets of films for each patient were reviewed separately in a randomized order and blinded fashion by two independent observers. Discrepancies were reviewed by a third observer and subsequently resolved by consensus. RESULTS: Staging assessments by both techniques were concordant in 51 of 52 cases: one patient was recorded as stage II on the alternate slice technique, but stage III with contiguous slices but this difference did not affect management. Inter-technique agreement was very good (kappa=0.97). The staging assessments showed discrepancies between the two observers in 12 of the 52 cases which were independent of technique (kappa=0.71; good agreement). Consensus review showed them to result from differences in perception in seven cases and differences in interpretation of abnormalities in five cases. CONCLUSION: Our findings support the use of an alternate 10 mm slice technique in the staging of lymphoma at initial diagnosis. Observer variation was greater than the difference between techniques.

Adolescent↗
PubMed1998

Imaging the thyroid.

Thyroid imaging has historically relied heavily on scintigraphy, although, not surprisingly in view of the superficial position of the gland, ultrasound has assumed an increasingly prominent role in recent years. The other cross-sectional imaging modalities can also be useful, and the emergence of new radiopharmaceuticals and the increasingly central role of fine needle aspiration cytology have further added to the range of diagnostic techniques available. This review attempts to summarize the current state of knowledge, and makes some suggestions for the most efficient use of imaging resources in the investigation of thyroid disease.

Goiter↗
PubMed1997

Comparison of dynamic contrast enhanced MRI and Doppler ultrasound in the pre-operative assessment of the portal venous system.

The purpose of this study was to compare dynamic contrast enhanced MRI (DCEMR) with Doppler ultrasound (US) in the assessment of portal venous anatomy and to analyse the causes of discrepancy. Over a 1 year period, 97 patients undergoing assessment prior to hepatic surgery underwent imaging of the liver and portal venous system using US with colour and spectral Doppler and MRI with axial T2 weighted spin echo (SE) and coronal oblique T1 weighted rapid gradient echo (GRE) imaging before and immediately after bolus injection of Gd-DTPA (0.1 mmol kg-1). When the US and MRI findings were discrepant, the images were reviewed by two observers and compared with surgical findings. US and DCEMR were concordant in 90 patients (portal vein patent in 80, occluded in 10). In three patients with cirrhosis and gross ascites the portal vein was reported as occluded on US and patent on MRI; surgery confirmed the MRI findings. In one patient the portal vein was patient on US but not on MRI, but there was a 3 week interval between the examinations. In three patients the portal vein was patent on US, but MRI detected occlusion of intrahepatic portal vein branches in two, and encasement of an intrahepatic branch in the third case. Spontaneous splenorenal shunts were seen in 15 patients only on MRI; varices were seen in 39 patients on MRI and in 22 patients on US. Both US and DCEMR contribute to the pre-operative assessment of the portal venous system. MRI provides additional information over US in assessing intrahepatic portal branches and detecting varices and splenorenal shunts, and is recommended for all surgical candidates and in patients with abnormal portal venous anatomy and equivocal US findings.

Adolescent↗
PubMed1996

Is computed tomography of the body overused? An audit of 2068 attendances in a large acute hospital.

Computed tomography (CT) delivers a substantial proportion of the medical radiation dose to the population. The National Radiological Protection Board (NRPB) recommends that "CT examinations should only be carried out after there has been proper clinical justification for the examination of each individual by an experienced radiologist". The aim of this study was to review the indications for body CT in a large acute hospital in order to identify groups of patients in whom CT might not be "clinically justified". We reviewed the age, sex and diagnosis of all patients undergoing CT of the abdomen and pelvis (including lumbar spine) in our department in 1992. All requests had been checked by a senior radiologist before booking. CT was performed in 1078 male patients and in 990 females. Patients examined for benign disease were younger (mean age 52 years) than patients with malignant disease (mean age 57 years). Of 915 examinations performed for benign disease, 293 (32%) were orthopaedic in nature and included 255 (87%) for back pain. CT was carried out for benign non-orthopaedic disease in 97 women under 50 years old, usually following other tests with inconclusive or normal results. 49 of these examinations were reported as normal. Of 191 patients who had more than one CT examination, 158 (83%) were undergoing follow-up for malignant disease. All 39 patients who underwent CT on three or more occasions had life-threatening conditions, either malignancy or complicated acute pancreatitis. We have been unable to find substantial numbers of patients in whom CT was performed inappropriately. Substitution of magnetic resonance imaging (MRI) for CT of the spine will help population dose reduction. The benign condition responsible for the largest radiation dose from CT is complicated acute pancreatitis, and it may be possible to substitute MRI for CT in these patients. Women under 50 years old with normal CT form an important group for clinical audit.

Adolescent↗
PubMed1995

Multispiral three-dimensional computed tomography in the investigation of craniosynostosis: technique optimization.

21 infants with craniosynostosis were studied with a new three-dimensional (3D) computed tomography (CT) methodology. We describe technique optimization using multiple spiral data acquisitions with low dose (85 mAs) technique. One caudal volume of 3 mm slice thickness was obtained with a further two volumes of 1 mm slice thickness at the vertex. Image reconstruction of spiral raw data allowed overlapping 3 mm sections to be generated without the dose increase that would result from conventional axial CT scanning. We illustrate common technical artefacts of 3D CT and explain their cause and solution. A dramatic dose reduction to the lens was achieved with no loss in 3D image quality. Lens dose was 8.91 mSv compared with 24.6 mSv using the standard paediatric head technique.

Craniosynostoses↗
PubMed1993

Corticosteroid therapy and intercurrent illness: the need for continuing patient education.

In patients receiving long-term therapeutic or replacement corticosteroids, delayed or inappropriate adjustment of steroid dosage during intercurrent illness may be fatal. We used a questionnaire to assess current levels of patient knowledge, awareness of the need for action during intercurrent illness and the frequency with which steroid warning cards and Medic Alert pendants were carried, in 61 patients on long-term replacement corticosteroids and in 40 patients receiving long-term therapeutic corticosteroids. Only 67 of the 101 patients taking corticosteroids were carrying a steroid warning card. Eleven of the 21 Medic Alert owners wore their pendants. Only 18 of the 41 patients in the therapeutic group and 41 of the 60 patients in the replacement group would take appropriate action during an intercurrent illness (P < 0.001). Lack of patient knowledge in this important area emphasizes the need for continuing and effective education of these groups of patients during follow-up. An information sheet detailing the exact changes to be made during intercurrent illness may help reinforce verbal advice.

Acute Disease↗
PubMed1990

Is antral gastrin important in the resistance of duodenal ulcers to H2 receptor antagonists or in recurrent ulceration after highly selective vagotomy?

Basal serum gastrin, integrated gastrin response to a meal, and integrated gastrin response to insulin induced hypoglycaemia were measured in 60 patients with duodenal ulcer before and after elective highly selective vagotomy to determine whether antral gastrin has a role in resistance to H2 receptor antagonist treatment which the patients had received before surgery or in the development of recurrent ulceration after vagotomy. The basal gastrin, integrated gastrin response to a meal, and the integrated gastrin response to insulin were similar in patients whose ulcers healed after H2 receptor agonist treatment or were refractory to at least three months of this treatment. The same parameters measured before or after highly selective vagotomy were similar in patients who eventually developed recurrent ulceration compared with those who did not. As expected the basal and meal stimulated (but not insulin stimulated) serum gastrin values increased after highly selective vagotomy. Ulcer patients with particularly high gastrin values (whether basal or stimulated) were not more resistant to H2 receptor antagonist treatment or prone to develop ulcer recurrence after highly selective vagotomy. This study suggests that antral gastrin is not important in 'resistance' of duodenal ulceration either to H2 receptor antagonist treatment or to highly selective vagotomy.

Adolescent↗
PubMedDate not supplied

Magnetic resonance cholangiopancreatography accurately predicts the presence or absence of choledocholithiasis.

Accurate common bile duct (CBD) imaging in patients with biliary calculi is an important determinant of specific therapy. Noninvasive methods to evaluate calculi in the CBD have limited accuracy and rely mainly on ultrasonography and computed tomography. Magnetic resonance cholangiopancreatography (MRCP) is a new noninvasive modality available to evaluate the biliary system. This study was undertaken to assess the accuracy of MRCP in predicting the presence or absence of CBD stones in patients at increased risk for choledocholithiasis. The medical records of 48 patients with a final diagnosis of biliary calculous disease undergoing MRCP between November 1995 and April 1997 were retrospectively reviewed. Three groups were identified: choledocholithiasis (n = 19), gallstone pancreatitis (n 5 11), and uncomplicated cholelithiasis (n = 18). In all patients the presence or absence of CBD calculi, as determined by MRCP, was correlated with the final diagnosis obtained from endoscopic retrograde cholangiopancreatography (ERCP) (n = 19), intraoperative cholangiography (n = 6), CBD exploration (n = 13), or clinical follow-up (n = 10). Sensitivity, specificity, and accuracy of MRCP were determined. The major clinical indications for MRCP in the 48 patients ware abnormal liver function tests followed by hyperamylasemia. Twenty patients were diagnosed with CBD stones and 28 were not. MRCP correctly predicted the presence of CBD stones in 19 of 20 patients and failed to detect CBD stones in one patient with gallstone pancreatitis. MRCP incorrectly predicted the presence of CBD stones in 3 of 28 patients ultimately found to have gallstones and no CBD stones. MRCP correctly predicted the absence of CBD stones in the other 25 patients including 10 patients with gallstone pancreatitis. Overall, MRCP had a sensitivity of 95%, a specificity of 89%, and an accuracy of 92%. MRCP is an accurate, noninvasive test for evaluating the CBD duct for the presence or absence of calculi in patients suspected of having CBD stones. Our data support the use of MRCP in the preoperative evaluation of these patients as findings may influence therapeutic decisions.

Adult↗