Tomographic ventilation/perfusion lung scintigraphy in the monitoring of the effect of treatment in pulmonary embolism: serial follow-up over a 6-month period.

BACKGROUND: Pulmonary embolism (PE) is a severe condition with nonspecific symptoms. Diagnosis relies on medical imaging but follow-up is currently based on clinical symptoms and general risk factors. The duration of anticoagulant treatment after an acute episode of PE is still subject to debate and the best method of identifying the risk of recurrence in individual patients is undefined. Tomographic lung scintigraphy [ventilation/perfusion single photon emission computed tomography (V/P SPECT)] has improved the diagnostic accuracy with regard to PE but has not been evaluated for PE follow-up. AIM: The aim of this prospective study was to quantitatively follow the natural history of treated PE using V/P SPECT, which could prove helpful in defining an anticoagulant treatment regime for individual patients. METHODS: Of 83 consecutive patients with clinically suspected PE examined with V/P SPECT, 23 patients with confirmed PE were followed by serial V/P SPECT examinations over a 6-month period. All patients were also followed clinically. RESULTS: The mean relative decrease in PE extent compared with the time of diagnosis was 54±26% at 2 weeks, 79±30% at 3 months, and 82±30% at 6 months. Significant resolution of mismatched perfusion defects occurred between V/P SPECT controls within the first 3 months of anticoagulation (P<0.001) but not thereafter. V/P SPECT identified four patients with chronic PE, even though all patients were free from symptoms at 3-month follow-up. CONCLUSION: Follow-up of PE with V/P SPECT is feasible to evaluate treatment effectiveness in individual patients and to identify patients that develop chronic PE. This study also confirms that resolution of perfusion defects after PE occurs within the first 3 months of treatment. It is therefore recommended that V/P SPECT follow-up should be considered at 3 months after diagnosis.

Lymphoscintigraphy and radiation--occupational exposure during sentinel node assay.

Ionizing radiation has many practical applications, but it is also, as it is well known, dangerous to human health. The purpose of this study was to estimate the dose and exposure for medical staff involved in sentinel node assay and to determine how safe this assay really is. The theoretical method was used for calculation. Three groups of medical staff were selected: nuclear medicine specialist, nuclear medicine technologist and a surgeon. The results obtained show that the most exposed staff member is nuclear medicine specialist and that dose received by the surgeon is smaller then the dose limit.

The relationship between the serum prostate specific antigen and whole body scintigraphy in prostate cancer patients after prostatectomy.

BACKGROUND AND AIM: Bone metastases are of the most frequent in prostate cancer. Serum prostate specific antigen--PSA has been suggested as an accurate means of monitoring prostate cancer. Whole body scintigraphy are currently the most widely used diagnostic procedures for metastases to the bone, the most common site of distant tumor spread. Aim of the study was to determinate relation between PSA level, number of metastases and 99mTc- MDP (methyl-diphosponate) uptake in patients with previous prostatectomy for prostate cancer. PATIENTS AND METHODS: Study enrolled 15 patients after previous prostatectomy for prostate cancer (histologically proven). Standard whole body scintigraphy (WBS) was performed 3 hours after intravenous application of 740 MBq 99mTc-MDP. Total PSA was measured by MEIA-Microparticle Enzyme Immunoassay. RESULTS: Group 1: 12/15 (80%) patients were with WBS detected metastases. Correlation of PSA level and number of detected bone metastases was good (r=0.79). Correlation of PSA level and uptake intensity of 99mTc-MDP (score 3) was positive and significant (r=0.706). CONCLUSION: PSA values were highly predictive for WBS results. PSA values correlated well with number of metastases. We propose no WBS in patients with normal PSA level. WBS is a sensitive diagnostic tool for detecting prostate cancer metastases to bone. PSA levels is good and simpler marker for disease progression, but that neither technique in isolation gives complete accuracy.