Pancreas divisum: A risk factor for pancreaticobiliary tumors - an analysis of 1628 MR cholangiography examinations.

PURPOSE: This retrospective study was conducted to evaluate the relationships between pancreas divisum, biliary duct anatomical variations and pancreaticobiliary tumors using magnetic resonance cholangiopancreatography (MRCP). MATERIALS AND METHOD: The MRCP examinations of 1628 patients were retrospectively reviewed for the presence of pancreas divisum, biliary duct anatomical variations and pancreaticobiliary tumors. Of these, 90 patients (31 men, 59 women) with a mean age of 62.6 years±15.8 (SD) (range: 22-101 years) had pancreas divisum. MRCP images were analyzed by two independent readers with discordances resolved by consensus opinion. RESULTS: A total of 1538/1628 patients (94.5%) had a dominant duct of Wirsung; of them 54/1538 patients (3.5%) had pancreaticobiliary tumors. A total of 90/1628 patients had pancreas divisum; of them, 7/90 patients (7.8%) had pancreaticobiliary tumors, including intrapancreatic mucinous neoplasm (n=3), ampullary carcinoma (n=2), pancreas carcinoma and gallbladder carcinoma (n=1 each). Pancreaticobiliary tumors were more frequent in patients with pancreas divisum than in those with a dominant duct of Wirsung (P=0.0383). CONCLUSIONS: The results of our study suggest that patients with pancreas divisum and biliary anatomical variations are more likely to develop pancreaticobiliary tumors and should be followed up closely using MRCP. However, our results should be confirmed by further prospective studies.

Renal artery stenosis in en-bloc pediatric renal transplant: demonstration by captopril-enhanced renal scintigraphy.

A double-pediatric kidney transplant recipient, who developed hypertension, was found to have unilateral renal artery stenosis. The stenosis was successfully assessed by single-dose 99mTc-diethylenetriaminepentaacetic acid renal scintigraphy, confirmed by renal arteriography, and treated by percutaneous transluminal angioplasty. This case illustrates the usefulness of Captopril-enhanced renography in screening en-bloc transplant patients suspected for renal vascular hypertension.

The relationship of SPECT scans to behavioral dysfunction in neuropsychiatric patients.

The authors describe 20 neuropsychiatric inpatients consecutively evaluated in the context of routine clinical care. Patients had both a neurological and psychiatric disorder. Each was clinically evaluated as part of a psychiatric hospitalization. DSM-III-R diagnoses, electroencephalograms, magnetic resonance imaging (MRI) or computed tomography (CT) scans of the brain, single photon emission computed tomography (SPECT) scans of the brain, and cognitive testing are reported. In only three cases were SPECT, MRI (or CT), and electroencephalogram all normal. SPECT abnormalities were associated with behavioral and cognitive presentations and with the hypothesized anatomical areas of dysfunction in 16 cases. In six cases SPECT and MRI were equivalent, involving structural lesions or normal scans. In only one case did MRI (or CT) detect deficits not revealed by SPECT, which were nonspecific white matter lesions and atrophy. The authors conclude that SPECT scans may be superior to structural brain scans in detecting clinically relevant deficits in neuropsychiatric patients, particularly when physiological lesions are involved.

Metastatic lesions arising in a Riedel's lobe. Findings from a sulfur colloid liver-spleen scan.

Clinically significant lesions originating within a Riedel's lobe are extremely rare. Characteristic findings from a Tc-99m SC liver-spleen scan of metastatic breast carcinoma arising in a Riedel's lobe are described.

The diagnosis of skull base metastases by radionuclide bone scan.

The differential diagnosis of multiple cranial nerve palsies in patients with cancer includes meningeal infections, meningeal carcinomatosis, and skull base metastases. In distinguishing these, spinal fluid analysis and skull base tomography should be helpful in most cases. In circumstances when results of skull base tomography are negative, radionuclide bone scans can demonstrate metastatic disease in the base of the skull, and it should be obtained in all patients who are highly suspicious for having skull base metastasis with negative skull base tomography, including computed tomography (CT).

Non-interventional background corrections for scintigrams.

A method is presented for the interpolation of optimally 'smooth' background correction matrices within arbitrarily shaped boundaries. Practical means of implementing this technique are discussed, along with series expansions for the special cases of square and round boundaries. This class of interpolation methods has the advantages over previous techniques of providing a unique mathematical solution, connecting exactly to count rates on the boundary, and containing no singularities. Clinical scintigraphic images and mathematically generated surfaces are used to test the different cases of the method, and it is shown that confining the boundary to a circle produces the most rapid convergence with the minimum deviation from ideal surfaces. Under common clinical conditions, these techniques lend themselves well to automated, non-interventional computer processing.

Hematogenous pyogenic vertebral osteomyelitis: diagnostic value of radionuclide bone imaging.

Hematogenous pyogenic vertebral osteomyelitis (HPVO) continues to be a diagnostic problem for clinicians due to nonspecific presentation of the disease (1,2). We reviewed our experience of the last 10 years to determine the diagnostic usefulness of radionuclide bone studies in this disease. We found 15 patients whose primary diagnosis was HPVO. Of the 15 patients, 12 had [99mTc]MDP bone scans which were all positive. Five of the 12 patients had positive [67Ga]citrate scans and one patient with chronic active HPVO had negative 67Ga and [111In]WBC bone images. At the same time, three patients' spine x-rays and one patient's CT scan of the vertebra were normal. Additionally, in three patients spine x-rays were interpreted as consistent with degenerative joint disease that contributed to the delay of the diagnosis. We conclude that when HPVO is suspected an abnormal [99mTc]MDP bone image increases the probability of the disease, even if the x-rays and CT scans of the spine are normal. An abnormal 67Ga image following an abnormal 99mTc bone image increases the specificity of the diagnosis. Normal [99mTc]MDP and [67Ga]citrate bone images of the vertebra virtually exclude the diagnosis of HPVO.

Right coronary artery-pulmonary artery arteriovenous fistula secondary to open heart surgery.

A patient is described who underwent atrial septal defect repair at age 12 and presented 16 years later with angina. Coronary angiography revealed a right coronary artery to pulmonary artery fistula that had developed at the site of the previous thoracotomy. This is the first report of an acquired fistula of this type developing secondary to trauma associated with open heart surgery. Diagnosis, shunt quantification and treatment are discussed.

Effect of narcotic premedication on scintigraphic evaluation of gallbladder perforation.

A case of gallbladder perforation is presented in which a small bile leak was demonstrated by cholescintigraphy while the patient was receiving meperidine, but not after meperidine was discontinued. The scintigrams obtained during meperidine therapy also showed a pattern of bile-duct obstruction. It is suggested that increased biliary pressure secondary to meperidine administration permitted visualization of the leak. Use of narcotic drugs may be a useful pharmacologic intervention in cases of peritonitis due to small or obscure bile leaks.

A new scintigraphic method for determining left ventricular volumes.

A new scintigraphic count-based method for measuring absolute left ventricular volumes is presented. It is a fast and simple technique that allows geometrical assumptions to be avoided and is free of radiation attenuation corrections. This method requires the acquisition of an image of the left ventricle in the right anterior oblique projection and the collection of gated blood pool images in the left anterior oblique projection. To assess the accuracy of the method scintigraphic stroke volumes were compared with those derived from thermodilution measurements during cardiac catheterization in 20 subjects, and to assess its precision the technique was applied to phantom data of known radionuclide volumes. Excellent correlations were found between the scintigraphic and both the thermodilution (r = .98) and phantom data (r = .99). The reproducibility (r = .97) of results was investigated by repeating data acquisition and analysis for 15 subjects on two different days, and the interobserver variability (r = .97) of the method was studied by having two computer operators calculate volumes for the same patient data for 20 randomly selected studies.

Diagnosis of non-Hodgkin's lymphoma intracerebral mass lesions. Usefulness of Tc-99m pertechnetate and Ga-67 citrate brain scans.

This paper summarizes the clinical and diagnostic features of five reports of patients with intracerebral, non-Hodgkin's lymphoma. In three patients the brain lesion was the only evidence of lymphoma, while two patients also had concomitant systemic involvement. Four patients had diffuse histiocytic lymphoma and one had a mixed type of malignant lymphoma. In all patients, Tc-99m and Ga-67 brain scans disclosed discrete areas of increased radionuclide uptake consistent with a mass. In each case, brain blood perfusion studies were normal and brain computerized tomographic (CT) scans and cerebral angiograms produced variable nondiagnostic patterns. Craniotomies in four patients provided histologic confirmation of the non-Hodgkin's lymphoma in the areas of abnormality. The remaining patient had systemic histiocytic lymphoma with concomitant brain lesions that responded to irradiation. The combined use of the above noninvasive modalities in correlation with clinical findings may result in more accurate prebiopsy diagnoses of intracerebral lymphoma.

Coronary artery fistula: estimation of shunt using 99m Tc-albumin particles.

A 60-year-old man presented with complaints on angina pectoris and was found to have a coronary artery fistula between his left main truck and main pulmonary artery. Particles of 99m Tc-Albumin were injected in the ostium of the left coronary artery, and differential radioactive counts were injected in the ostium of the left coronary artery, and differential radioactive counts were obtained over both lung fields and myocardium. The degree of left to right shunt was calculated at 56% of total left coronary artery flow. The patient underwent ligation of the fistula without any complications. This case report represents a new application of myocardial radioisotopic scanning.

Myocardial scintigraphy. Post-Vineberg study.

In order to assess myocardial perfusion of Vineberg implants, tracer particles (99mCc and 131I-MAA) were injected into the internal mammary implants of 7 patients (6 years after the operation) after selective contrast visualization. The myocardial perfusion images were correlated with the internal mammary arteriographic findings. Of those patients with patent implants with communication, the myocardial scintigrams demonstrated even distribution of radioactive particles reflecting myocardial perfusion at the capillary or precapillary bed.

Reversal of pulmonary circulation.

The preliminary results and the technique of total reversal of the pulmonary circulation (RPC) are presented. Total RPC is technically feasible and not incompatible with life. It affords a new experimental model for in vivo study of pulmonary pathophysiology. The influence of this reversal on blood oxygenation, on pulmonary vascular resistance, and on established pulmonary hypertension, as well as its reaction to hypoxia and acidosis, needs further investigation. RPC may have clinical implications in essential pulmonary hypertension and congenital pulmonary vascular anomalies.