Canadian Association of Radiologists Journal

A recent publication from our centre revealed a disturbing finding of a significant incidence of adult fingers seen on the pediatric intensive care unit (PICU) chest radiographs. This is inappropriate occupational exposure to diagnostic radiation. We hypothesized that the incidence of adult fingers on PICU chest radiographs would decline after radiation safety educational seminars were given to the medical radiation technologists and PICU staff.

The present study's objectives were addressed by using a pretest-posttest design. Two cross-sectional PICU chest radiograph samples, taken before and after the administration of radiation safety education for our medical radiation technologists and PICU staff, were compared by using a χ² test.

There was a 61.2% and 76.9% reduction in extraneous adult fingers, directly exposed to the x-ray beam and those seen in the coned regions of the film, respectively, on PICU chest radiographs (66.7% reduction overall). This reduction was statistically significant (χ² = 20.613, P < .001).

Limiting unnecessary occupational radiation exposure is a critical issue in radiology. There was a statistically and clinically significant association between radiation safety education and the decreased number of adult fingers seen on PICU chest radiographs. This study provides preliminary evidence in favour of the benefit of radiation safety seminars.

To review the association of an abnormal prenatal sonogram with most recent serum creatinine in patients with proven posterior urethral valves (PUV).

Since 1992, all live-born patients between 1992–2004 with clinically proven PUV, with postnatally proven PUV, from 2 pediatric tertiary care centers, were reviewed for age at diagnosis, most recent serum creatinine, presence of chronic renal failure (CRF) (serum creatinine >2 standard deviations above normal for age), or end stage renal disease (dialysis or transplant). Available antenatal reports from the 2 centres and surrounding community hospitals were reviewed for gestational age (GA) at the time of ultrasound, volume of amniotic fluid, and urinary-tract abnormality.

Thirty-four patients with proven PUV and prenatal sonograms were identified (1992–2004). Eighteen patients had abnormalities on their prenatal sonogram, with poor outcome in 5 (mean follow-up, 8 years [1–13 y]). No specific features were identified on prenatal sonogram. Sixteen patients had normal prenatal sonograms, with poor outcomes in 2 (mean follow-up, 8 years [3–13y]). There is an increased risk of an abnormal serum creatinine among those patients with an abnormal prenatal study, odds ratio (OR) 2.6 (95% confidence interval, 0.35–32).

PUV represents a spectrum of disease severity. A normal prenatal ultrasound does not preclude PUV. The majority of patients with a normal prenatal examination have good outcomes. The OR suggests that there may be increased risk for poor outcome in those with an abnormal prenatal examination. A multicenter study is necessary to obtain a larger sample size and more precise ORs.

To evaluate the use of anxiolytics in adult outpatient magnetic resonance imaging (MRI) centres and to determine whether utilisation is optimal based on the pharmacology of the drugs used, who prescribes these drugs, and how patients are managed after administration.

Identical paper and Web-based surveys were used to anonymously collect data about radiologists' use of anxiolytic agents for adult outpatient MRI examinations. The survey questions were about the type of facility, percentage of studies that require sedation, the drug used and route of administration, who orders the drug, timing of administration, patient monitoring during and observation after the study, use of a dedicated nurse for monitoring, and use of standard sedation and discharge protocols. The χ² analysis for statistical association among variables was used.

Eighty-five of 263 surveys were returned (32% response rate). The radiologist ordered the medication (53%) in slightly more facilities than the referring physician (44%) or the nurse. Forty percent of patients received medication 15–30 minutes before MRI, which is too early for peak effect of oral or sublingual drugs. Lorazepam was most commonly used (64% first choice). Facilities with standard sedation protocols (56%) were more likely to use midazolam than those without standard sedation protocols (17% vs 10%), to have a nurse for monitoring (P = .032), to have standard discharge criteria (P = .001), and to provide written information regarding adverse effects (P = .002).

Many outpatients in MRI centres may be scanned before the peak effect of anxiolytics prescribed. A standard sedation protocol in such centres is associated with a more appropriate drug choice, as well as optimized monitoring and postprocedure care.

To evaluate the effectiveness in diagnosing mammographically and sonographically occult breast lesions by using magnetic resonance imaging (MRI) guided vacuum-assisted breast biopsy in patients who presented to a community-based hospital with a newly established breast MRI program.

The records of 142 consecutive patients, median age of 55 years, who had undergone MRI-guided biopsy at our institution between July 2006 and July 2007 were reviewed. From these patients, 197 mammographically and sonographically occult lesions were biopsied at the time of discovery. The pathology was then reviewed and correlated with the MRI findings.

Cancer was present and subsequently discovered in 8% of the previously occult lesions (16/197) or 11% of the women studied (16/142). Of the cancerous lesions, 56% were invasive carcinomas (9/16) and 44% were ductal carcinomas in situ (7/16). Fourteen percent of the discovered lesions (28/197) were defined as high risk and included atypical ductal hyperplasia, atypical lobular hyperplasia, lobular carcinoma in situ, and radial scar. In total, occult cancerous and high-risk lesions were discovered in 22% of the found lesions (44/197) or 31% of the women who underwent MRI-guided biopsy (44/142).

This study demonstrated that detection of cancerous and high-risk lesions can be significantly increased when an MRI-guided biopsy program is introduced at a community-based hospital. We believe that as radiologists gain confidence in imaging and histologic correlation, community-based hospitals can achieve similar rates of occult lesion diagnosis as those found in data emerging from academic institutions.