Israel Medical Association Journal

Objectives: To evaluate the predictive value of V/Q scanning in patients with impaired renal function.

Methods: We assessed all patients with impaired renal function who underwent V/Q scanning. The patients studied included those who also had CTPA (group 1) and those who did not (group 2). We recorded the results of V/Q scanning, chest X-rays, CTPA, D-dimer levels, ultrasound of deep veins, and clinical probability for PE (Wells' score) in group 1. CTPA results were considered true results. Anticoagulant treatment was documented in all the patients.

Results: Of the 45 patients in group 1, 12 (22%) had positive CTPA for PE. The positive predictive value (PPV) for patients with high probability results on V/Q scanning for PE was 30%. Restricting results to D-dimer levels ≥ 1000 ng/ml added little to this value. Restricting results to Wells’ score ≥ 7 resulted in 72% PPV. The negative predictive values for low or moderate probability were ~79 % and ~67% respectively. Of the 95 patients in group 2, all those with high probability for PE were treated with anticoagulants.

Conclusions: Patients with impaired renal function and high probability for PE on V/Q scanning had very low PPV for PE. Due to the lack of CTPA studies, patients with high probability for PE on V/Q scanning were treated with anticoagulants.

Background: Cardiac computed tomography scans influde several extra-cardiac structures such as mediastinum, lung parenchyma and upper abdominal organs. A variety of abnormalities in those structures might be clinically important and in some cases might explain the patient's complaints.

Objectives: To analyze consecutive cardiac computed tomography examinations for the prevalence and clinical significance of extra-cardiac findings.

Methods: Cardiac CT scans of 134 sequential patients (104 males, 30 females) aged 20–77 years (mean 54 years) with suspected coronary artery disease were prospectively and independently reviewed by a consensus of two radiologists for the presence of lung, mediastinal, pleural, upper abdominal and skeletal abnormalities. CT scans with extra-cardiac abnormalities were divided into two groups: group A – defined as "clinically significant" or "potentially significant findings" – consisted of patients requiring further evaluation or follow-up, and group B – "clinically non-significant findings."

Results: Extra-cardiac abnormalities were found in 103 of the 134 patients (76.8%). Group A abnormalities were found in 52/134 patients (39%), while group B abnormalities were seen in 85/134 (63%). The most common abnormalities in group A were non-calcified lung nodules (> 4 mm) noted in 17/134 patients (13%), followed by enlarged mediastinal lymph nodes (> 10 mm) in 14/134 (10%), diaphragmatic hernia (2 cm) in 12/134 (9%), moderate or severe degenerative spine disease in 12/134 (9%), and emphysema and aortic aneurysm in 6 patients each (4.5%). A malignant lung tumor was noted in one patient.

Conclusions: There is a high prevalence of non-cardiac abnormalities in patients undergoing CCT[1]. Clinically significant or potentially significant findings can be expected in 40% of patients who undergo CCT, and these will require further evaluation and follow-up. The reporting radiologist should be experienced in chest imaging and aware of the large variety of non-cardiac findings in CCT that might explain the patient's complaints. 

Background: The use of computed tomography in Israel has been growing rapidly during recent decades. The major drawback of this important technology is the exposure to ionizing radiation, especially among children, who have increased organ radiosensitivity and a long lifetime to potentially develop radiation-related cancer.

Objective: To estimate the number of excess lifetime cancer deaths related to annual CT scans performed in children in Israel.

Methods: We used CT scan utilization data from 1999 to 2003 obtained from the second largest health management organization in the country to project age and gender-specific CT scan use nationwide. Based on published organ doses for common CT examinations and radiation-related cancer mortality risk estimates from studies in survivors of the atomic bomb, we estimated the excess lifetime risks for cancer mortality attributed to use of CT in children and adolescents (up to 18 years old) in Israel.

Results: We estimated that 17,686 pediatric scans were conducted annually in Israel during 1999–2003. We project that 9.5 lifetime deaths would be associated with 1 year of pediatric CT scanning. This number represents an excess of 0.29% over the total number of patients who are eventually estimated to die from cancer in their lifetime.

Conclusions: Pediatric CT scans in Israel may result in a small but not negligible increased lifetime risk for cancer mortality. Because of the uncertainty regarding radiation effects at low doses, our estimates of CT-related cancer mortality should be considered with caution. Nevertheless, physicians, CT technologists, and health authorities should work together to minimize the radiation dose for children to as low as reasonably achievable and encourage responsible use of this essential diagnostic tool.