Single-photon emission computed tomography (SPECT) for assessment of hepatic lesions.

Single-photon emission computed tomography (SPECT) and conventional scintigraphy were compared in 130 patients examined to assess hepatic involvement in malignant disease. Transmission computed tomography (TCT) served as the reference method against which SPECT and conventional scintigraphy were compared. The sensitivity of SPECT was calculated for lesions grouped according to diameter as well as location. The Bayesian theorem was used to assess the reliability of both SPECT and conventional scintigraphy. SPECT identified only 52% of lesions with a diameter of 1.5-2.0 cm. It was also shown that the sensitivity of SPECT was lowest for small lesions in the middle third of the liver. A comparison of the final diagnosis demonstrated that SPECT had greater sensitivity, specificity, and accuracy than conventional scans, and is superior at low disease prevalence. At high disease prevalence, SPECT has a lower rate of false negatives. SPECT appears to be the superior imaging modality for evaluation of the liver in malignant disease.

Hypertension associated with massive, bilateral, posture-dependent renal dysfunction.

Hippurate function scintiscans were obtained in prone and standing positions in a group of 76 patients with concurrent hypertension and nephroptosis. TWelve of these patients had massive, bilateral disturbance of intrarenal hippurate transport in the standing position; hippurate transport was normal in the prone position. This pattern was present in only three of 120 normotensive patients with nephroptosis. To investigate the importance of nephroptosis, 87 other hypertensive patients were examined. Eighteen of these patients demonstrated posture-dependent tubular dysfunction, but only four had nephroptosis. The results suggest a direct relationship between bilateral posture-dependent tubular dysfunction and hypertension.

Posture-induced disturbance of pertechnetate flow and I-123 iodohippurate transport in some renal graft recipients with hypertension.

Iodohippurate renography and rapid serial scintigrams with pertechnetate were done in 27 allograft recipients in supine and standing positions. Posture-dependent iodohippurate transport and/or disturbance of pertechnetate flow pattern was found in nine of those examined. Patients demonstrating these abnormalities were found to be hypertensive. We suggest a causal relationship between posttransplant hypertension and the described posture-induced alterations of tracer transit.

Renal graft evaluation with pertechnetate and I-131 Hippuran. A comparative clinical study.

This retrospective study compared standard clinical and biochemical data from 50 graft recipients against 533 I-131 Hippuran sequential scintigrams and 515 [99mTc]pertechnetate serial scintigrams. All grafts included in this study are cadaver kidneys. The majority of the studies were made during the early posttransplantation period. Anuria or oliguria of at least 4 days duration was seen in 18 patients. The study spans 574 days of oliguria during which 136 dual-tracer studies were made. I-131 Hippuran renography of functioning grafts was carried out 397 times, and the Tc-99m sequential scintigraphy 379 times. In all, 47 espisodes of actue rejection were registered clinically in functioning gfafrs, 36 of which were recognized during Hippuran renography and 38 with the pertechnetate study. False-positive errors were seen 12 times during renography. The study also demonstrated that furosemide will significantly and predictably influence renography and the pertechnetate study. This seems noteworthy since furosemide is extensively used in posttransplant management.