Canadian Association of Radiologists Journal

In Canada, recommendations for clinical management of hereditary breast and ovarian cancer among individuals carrying a deleterious BRCA1 or BRCA2 mutation have been available since 2007. Eight years later, very little is known about the uptake of screening and risk-reduction measures in this population. Because Canada's public health care system falls under provincial jurisdictions, using provincial health care administrative databases appears a valuable option to assess management of BRCA1/2 mutation carriers. The objective was to explore the usefulness of public health insurance administrative databases in British Columbia, Ontario, and Quebec to assess management after BRCA1/2 genetic testing.

Official public health insurance documents were considered potentially useful if they had specific procedure codes, and pertained to procedures performed in the public and private health care systems.

All 3 administrative databases have specific procedures codes for mammography and breast ultrasounds. Only Quebec and Ontario have a specific procedure code for breast magnetic resonance imaging. It is impossible to assess, on an individual basis, the frequency of others screening exams, with the exception of CA-125 testing in British Columbia. Screenings done in private practice are excluded from the administrative databases unless covered by special agreements for reimbursement, such as all breast imaging exams in Ontario and mammograms in British Columbia and Quebec. There are no specific procedure codes for risk-reduction surgeries for breast and ovarian cancer.

Population-based assessment of breast and ovarian cancer risk management strategies other than mammographic screening, using only administrative data, is currently challenging in the 3 Canadian provinces studied.

Per the Breast Imaging Reporting and Data System (BI-RADS) manual, a lesion designated as BI-RADS 3 should have less than a 2% chance of becoming malignancy. With this study, we evaluated the outcome of patients given a BI-RADS 3 designation in the community hospital. Specifically, whether our cancer detection rate for BI-RADS 3 lesions was less than 2% and comparable to rates obtained at other institutions.

The records of 1037 patients given a BI-RADS 3 on screening mammogram were reviewed over a 1-year period between May 2007 and May 2008. A total of 142 of these patients were lost to follow-up, leaving 885 patients. Some of these patients had more than 1 BI-RADS 3 lesion during this study period, yielding a total of 923 BI-RADS 3 lesions to evaluate out of the 885 patients remaining. Of these, 478 of the patients' lesions were biopsied. The pathology was then reviewed to determine whether the lesions were cancerous.

Only 6 of the 882 lesions initially classified as a BI-RADS 3 were later diagnosed as cancer, or 0.65% of the study population. The positive predictive value of receiving a BI-RADS 3 was 99.3%, which demonstrates a high accuracy in predicting that a lesion is not cancerous.

Most lesions that are diagnosed as a BI-RADS 3 have a very low probability of eventually being diagnosed as cancer. The findings from this study are comparable to studies performed at other institutions.

After imaging assessment of an abnormal screening mammogram, a follow-up examination 6 months later is recommended to some women. Our aim was to identify which characteristics of lesions, women, and physicians are associated to such short-interval follow-up recommendation in the Quebec Breast Cancer Screening Program.

Between 1998 and 2008, 1,839,396 screening mammograms were performed and a total of 114,781 abnormal screens were assessed by imaging only. Multivariate analysis was done with multilevel Poisson regression models with robust variance and generalized linear mixed models.

A short-interval follow-up was recommended in 26.7% of assessments with imaging only, representing 2.3% of all screens. Case-mix adjusted proportion of short-interval follow-up recommendations varied substantially across physicians (range: 4%-64%). Radiologists with high recall rates (≥15%) had a high proportion of short-interval follow-up recommendation (risk ratio: 1.82; 95% confidence interval: 1.35-2.45) compared to radiologists with low recall rates (<5%). The adjusted proportion of short-interval follow-up was high (22.8%) even when a previous mammogram was usually available.

Short-interval follow-up recommendation at assessment is frequent in this Canadian screening program, even when a previous mammogram is available. Characteristics related to radiologists appear to be key determinants of short-interval follow-up recommendation, rather than characteristics of lesions or patient mix. Given that it can cause anxiety to women and adds pressure on the health system, it appears important to record and report short-interval follow-up and to identify ways to reduce its frequency. Short-interval follow-up recommendations should be considered when assessing the burden of mammography screening.

The study sought to compare performance indicators of computed radiography (CR) using different plate readers, digital direct radiography (DR), and screen-film mammography (SFM) in a population-based screening program.

This analysis involved women 50-69 years of age who participated in the breast screening program of Quebec (Canada) and who had screening mammogram between January 1, 2007, and September 30, 2012. The detection rate, recall rate, and positive predictive value of CR (n = 672,125 mammograms) and DR (n = 60,023) were compared to SFM (n = 782,894) using mixed-effect logistic regression, adjusting for potential confounders. No institutional review board approval was required.

CR was not associated with change in cancer detection rate (odds ratio [OR]: 0.95; 95% confidence interval [CI]: 0.88-1.03), but with a small increase in recall rate (OR: 1.03; 95% CI: 1.01-1.06) compared to SFM. The association of CR with recall rate varies with the CR plate reader manufacturer (P < .0001). DR was not associated with change in detection rate (OR: 1.06; 95% CI: 0.89-1.25), but with an increase in the recall rate (OR: 1.25; 95% CI: 1.19-1.30) compared to SFM.

In our screening program, digital mammograms gave detection rates equivalent to those of SFM, but with an increase of recall rate, particularly for DR. If this situation persists, the adoption of DR may increase the adverse effects of screening with little or no benefit for women.

Preservation of patient privacy and dignity are basic requirements for all patients visiting a hospital. The purpose of this study was to perform an audit of patients' satisfaction with privacy whilst in the Department of Medical Imaging (MI) at the Civic Campus of the Ottawa Hospital.

Outpatients who underwent magnetic resonance imaging (MRI), computed tomography (CT), ultrasonography (US), and plain film (XR) examinations were provided with a survey on patient privacy. The survey asked participants to rank (on a 6-point scale ranging from 6 = excellent to 1 = no privacy) whether their privacy was respected in 5 key locations within the Department of MI. The survey was conducted over a consecutive 5-day period.

A total of 502 surveys were completed. The survey response rate for each imaging modality was: 55% MRI, 42% CT, 45% US, and 47% XR. For each imaging modality, the total percentage of privacy scores greater than or equal to 5 were: 98% MRI, 96% CT, 94% US, and 92% XR. Privacy ratings for the MRI reception and waiting room areas were significantly higher in comparison to the other imaging modalities (P = .0025 and P = .0227, respectively).

Overall, patient privacy was well respected within the Department of MI.

To minimize the burden of overutilisation of lumbar spine magnetic resonance imaging (MRI) on a resource-constrained public healthcare system, it may be helpful to image some patients with mechanical low-back pain (LBP) using a simplified rapid MRI screening protocol at 1.5-T. A rapid-acquisition 3-dimensional (3D) SPACE (Sampling Perfection with Application-optimized Contrasts using different flip angle Evolution) sequence can demonstrate common etiologies of LBP. We compared lumbar spinal canal stenosis (LSCS) and neural foraminal stenosis (LNFS) assessment on 3D SPACE against conventional 2-dimensional (2D) MRI.

We prospectively performed 3D SPACE and 2D spin-echo MRI sequences (axial or sagittal T1-weighted or T2-weighted) at 1.5-T in 20 patients. Two blinded readers assessed levels L3-4, L4-5 and L5-S1 using: 1) morphologic grading systems, 2) global impression on the presence or absence of clinically significant stenosis (n = 60 disc levels for LSCS, n = 120 foramina for LNFS). Reliability statistics were calculated.

Acquisition time was ∼5 minutes for SPACE and ∼20 minutes for 2D MRI sequences. Interobserver agreement of LSCS was substantial to near perfect on both sequences (morphologic grading: kappa [k] = 0.71 SPACE, k = 0.69 T2-weighted; global impression: k = 0.85 SPACE, k = 0.78 T2-weighted). LNFS assessment had superior interobserver reliability using SPACE than T1-weighted (k = 0.54 vs 0.37). Intersequence agreement of findings between SPACE and 2D MRI was substantial to near perfect by global impression (LSCS: k = 0.78 Reader 1, k = 0.85 Reader 2; LNFS: k = 0.63 Reader 1, k = 0.66 Reader 2).

3D SPACE was acquired in one-quarter the time as the conventional 2D MRI protocol, had excellent agreement with 2D MRI for stenosis assessment, and had interobserver reliability superior to 2D MRI. These results justify future work to explore the role of 3D SPACE in a rapid MRI screening protocol at 1.5-T for mechanical LBP.

The study sought to evaluate the potential of diffusion-weighted magnetic resonance imaging to detect changes in liver diffusion in benign and malignant distal bile duct obstruction and to investigate the effect of the choice of b-values on apparent diffusion coefficient (ADC).

Diffusion-weighted imaging was acquired with b-values of 200, 600, 800, and 1000 s/mm². ADC values were obtained in 4 segments of the liver. The mean ADC values of 16 patients with malignant distal bile duct obstruction, 14 patients with benign distal bile duct obstruction, and a control group of 16 healthy patients were compared.

Mean ADC values for 4 liver segments were lower in the malignant obstruction group than in the benign obstruction and control groups using b = 200 s/mm² (P < .05). Mean ADC values of the left lobe medial and lateral segments were lower in the malignant obstruction group than in the benign obstructive and control groups using b = 600 s/mm² (P < .05). Mean ADC values of the right lobe posterior segment were lower in the malignant and benign obstruction groups than in the control group using b = 1000 s/mm² (P < .05). Using b = 800 s/mm², ADC values of all 4 liver segments in each group were not significantly different (P > .05). There were no correlations between the ADC values of liver segments and liver function tests.

Measurement of ADC shows good potential for detecting changes in liver diffusion in patients with distal bile duct obstruction. Calculated ADC values were affected by the choice of b-values.

The study sought to assess how academic interventional radiologists determine and disclose to patients the intraprocedural role of radiology residents in the interventional radiology (IR) suite.

A qualitative study consisting of in-person interviews with 9 academic interventional radiologists from 3 hospitals was conducted. Interviews were transcribed, and underwent modified thematic analysis.

Seven themes emerged. 1) Interventional radiologists permit residents to perform increasingly complex procedures with graded responsibility. While observed technical ability is important in determining the extent of resident participation, possessing good judgement and knowing personal limitations are paramount. 2) Interventional radiologists do not explicitly inform patients in detail about residents' intraprocedural role, as trainee involvement is viewed as implicit at academic institutions. 3) While patients are advised of resident participation in IR procedures, detailed disclosure of their role is viewed as potentially detrimental to both patient well-being and trainee education. 4) Interventional radiologists believe that patients might be less likely to refuse resident involvement if they meet them prior to procedures. 5) While it is rare that patients refuse resident participation in their care, interventional radiologists' duty to respect patient autonomy supersedes their obligation to resident education. 6) Interventional radiologists are responsible for any intraprocedural, trainee-related complication. 7) Trainees should be present when complications are disclosed to patients.

Interventional radiologists recognize the confidence placed in them, and they do not inform patients in detail about residents' role in IR procedures. Respecting patient autonomy is paramount, and while rare, obeying patients' wishes can potentially be at the expense of resident education.

Traumatic bowel and mesenteric injury (TBMI), although an uncommon entity, can be lethal if not detected and treated in a timely manner. The purpose of our study was to evaluate the diagnostic accuracy of 64-slice multidetector computed tomography (MDCT) for the detection of TBMI in patients at our level 1 trauma centre.

We used our hospital's trauma registry to identify patients with a diagnosis of TBMI from January 1, 2006, to June 30, 2013. Only patients who had a 64-slice MDCT scan at presentation and subsequently underwent laparotomy or laparoscopy were included in the study cohort. Using the surgical findings as the gold standard, the accuracy of prospective radiology reports was analyzed.

Of the 4781 trauma patients who presented to our institution, 44 (0.92%) had surgically proven TBMI. Twenty-two of 44 were excluded as they did not have MDCT before surgery. The study cohort consisted of 14 males and 8 females with a median age of 41.5 years and a median injury severity score of 27. In total 17 of 22 had blunt trauma and 5 of 22 had penetrating injury. A correct preoperative imaging diagnosis of TBMI was made in 14 of 22 of patients. The overall sensitivity of the radiology reports was 63.6% (95% confidence interval [CI]: 41%-82%), specificity was 79.6% (95% CI: 67%-89%), PPV was 53.9% (95% CI: 33%-73%), and the NPV was 85.5% (95% CI: 73%-94%). Accuracy was calculated at 75.3%. However, only 59% (10 of 17) of patients with blunt injury had a correct preoperative diagnosis. Review of the findings demonstrated that majority of patients with missed blunt TBMI (5 of 7) demonstrated only indirect signs of injury.

The detection of TBMI in trauma patients on 64-slice MDCT can be improved, especially in patients presenting with blunt injury. Missed cases in this population occurred because the possibility of TBMI was not considered despite the presence of indirect imaging signs. The prospective diagnosis of TBMI remains challenging despite advances in CT technology and widespread use of 64-slice MDCT.