The choice of diagnostic modality influences the proportion of low muscle strength, low muscle mass, and sarcopenia in colorectal cancer patients.

BACKGROUND AND AIMS: Low muscle strength, low muscle mass, and sarcopenia have a negative impact on health outcomes in colorectal cancer (CRC) patients. Different diagnostic modalities are used to identify these conditions but it is unknown how well the modalities agree. The aim of this study was to compare different diagnostic modalities by means of calculating the proportion of low muscle strength, low muscle mass, and sarcopenia in CRC patients, and to investigate the agreement for sarcopenia between the various modalities. METHODS: Men and women participating in the Norwegian Dietary Guidelines and colorectal cancer Survival (CRC-NORDIET) study were included in the analyses. Cut-off values for low muscle strength, low muscle mass, and sarcopenia were defined according to the second consensus set by the European Working Group on Sarcopenia in Older People (EWGSOP2). The diagnostic modalities used to assess muscle strength were handgrip strength and the sit-to-stand test. For muscle mass, computed tomography, dual-energy X-ray absorptiometry (DXA), multi-frequency bioelectrical impedance analysis (MF-BIA), and single-frequency BIA (SF-BIA) were applied. Cohen's kappa was calculated to determine the agreement for low muscle strength and confirmed sarcopenia between diagnostic modalities. RESULTS: Five hundred and three men and women (54 % men, mean age of 66 (range 50-80) years old) were included in the analysis. As much as 99 % (n = 70) of the population was identified with low muscle mass by MF-BIA, while the other modalities identified 9-49 % as having low muscle mass. Handgrip strength identified a lower proportion of low muscle strength as compared with the sit-to-stand test (4 % vs. 8 %). When applying various combinations of diagnostic modalities for low muscle strength and low muscle mass, the proportion of sarcopenia was found to be between 0.3 and 11.4 %. There was relatively poor agreement between the different diagnostic modalities with Cohen's Kappa ranging from 0.0 to 0.55, except for the agreement between SF-BIASergi and MF-BIASergi, which was 1. CONCLUSION: The proportion of low muscle strength, low muscle mass, and sarcopenia in CRC patients varied considerably depending on the diagnostic modalities used. Further studies are needed to provide modality-specific cut-off values, adjusted to sex, age and body size.

Computed tomography for visible haematuria - a single nephrographic phase is sufficient for detecting renal cell carcinoma.

OBJECTIVES: No previous studies have compared two computed tomography (CT) protocols in patients presenting with visible haematuria, and most patients undergo a multiphase CT in order to detect upper tract malignancies. We aimed to prospectively compare the diagnostic performance of single- and four-phase CT for detecting renal cell carcinoma (RCC) in patients with visible haematuria. MATERIALS & METHODS: 'A Prospective Trial for Examining Hematuria using Computed Tomography' (PROTEHCT) was a single-centre prospective paired diagnostic study in patients referred for CT due to painless visible haematuria between September 2019 and June 2021. All patients underwent four-phase CT (control) from which a single nephrographic phase dual energy CT (experimental) was extracted. Both were independently assessed for RCC by randomised radiologists. Histologically verified RCC defined a positive reference standard. Follow-up ascertainment of RCC diagnosis was completed in May 2022. Descriptive statistics were used to calculate the accuracies. Inter-reader agreement was assessed by kappa statistics. RESULTS: A total of 308 patients (median age, 68 years [interquartile range 53-77, range 18-96], 250 males) were included for analysis. RCC was diagnosed in seven (2.3%) patients during a median follow-up time of 19 months (interquartile range: 15-25). For the control and experimental CT, sensitivity was 100% versus 100%, specificity was 97% versus 98% and accuracy 97% versus 97%. The positive predictive value was 44% versus 50%, and the negative predictive value was 100% versus 100%. The agreement between the control and experimental CT was 98% (k = 0.79). CONCLUSION: A single nephrographic phase dual energy CT is sufficient for detecting RCC in patients with visible haematuria.

MRI segmentation of tooth tissue in age prediction of sub-adults - a new method for combining data from the 1st, 2nd, and 3rd molars.

PURPOSE: We aimed to establish a model combining MRI volume measurements from the 1st, 2nd and 3rd molars for age prediction in sub-adults and compare the age prediction performance of different combinations of all three molars, internally in the study cohort. MATERIAL AND METHOD: We examined 99 volunteers using a 1.5 T MR scanner with a customized high-resolution single T2 sequence. Segmentation was performed using SliceOmatic (Tomovision©). Age prediction was based on the tooth tissue ratio (high signal soft tissue + low signal soft tissue)/total. The model included three correlation parameters to account for statistical dependence between the molars. Age prediction performance of different combinations of teeth for the three molars was assessed using interquartile range (IQR). RESULTS: We included data from the 1st molars from 87 participants (F/M 59/28), 2nd molars from 93 (F/M 60/33) and 3rd molars from 67 (F/M 45/22). The age range was 14-24 years with a median age of 18 years. The model with the best age prediction performance (smallest IQR) was 46-47-18 (lower right 1st and 2nd and upper right 3rd molar) in males. The estimated correlation between the different molars was 0.620 (46 vs. 47), 0.430 (46 vs. 18), and 0.598 (47 vs. 18). IQR was the smallest in tooth combinations including a 3rd molar. CONCLUSION: We have established a model for combining tissue volume measurements from the 1st, 2nd and 3rd molars for age prediction in sub-adults. The prediction performance was mostly driven by the 3rd molars. All combinations involving the 3rd molar performed well.

Effect of a one-year personalized intensive dietary intervention on body composition in colorectal cancer patients: Results from a randomized controlled trial.

BACKGROUND & AIMS: Changes in body composition may affect colorectal cancer (CRC) patient's risk of cancer recurrence, secondary cancer, and other chronic diseases. The suggested interventions for changes in body composition such as low muscle mass or high fat mass, are diet and physical activity. Nevertheless, there is limited evidence of how dietary intervention alone can impact body composition. This study aimed to investigate the effect of a 6 and 12 month dietary intervention with a focus on healthy eating according to Norwegian food-based dietary guidelines on weight and body composition in patients with CRC stage I-III, post-surgery. METHODS: This study included participants from the randomized controlled trial CRC-NORDIET study 2-9 months after surgery. The intervention group received an intensive dietary intervention, while the control group underwent similar measurements, but no dietary intervention. Body composition was measured with Lunar iDXA, and the results were analyzed using linear mixed models. RESULTS: A total of 383 participants were included, 192 in the intervention group and 191 in the control group. After 6 months, the intervention group showed a 0.7 kg lower mean weight gain (p = 0.020) and 0.6 kg lower fat mass gain (p = 0.019) than the control group, but no difference at 12 months. Moreover, the fat mass increase was 0.5 percentage points lower at 6 months (p = 0.012), and 0.7 percentage points lower at 12 months (p = 0.011) in the intervention group compared to the controls. At 6 months, the intervention group had 63 g lower gain of visceral adipose tissue compared to the control group (p = 0.031). No differences were seen for fat-free mass or subcutaneous adipose tissue at any time point. The intervention group showed a lower increase in the ratio between fat mass and fat-free mass at both 6 months (p = 0.025) and 12 months (p = 0.021). CONCLUSION: The dietary intervention reduced the increases in total weight and fat masses, without changing fat-free mass. Although the individual changes are small, the dietary intervention may have resulted in an overall more favourable body composition profile. These findings suggest that dietary intervention may be part of a treatment strategy for prevention of weight and fat mass gain in CRC survivors.

Prediction of Age Older than 18 Years in Sub-adults by MRI Segmentation of 1st and 2nd Molars.

PURPOSE: To investigate prediction of age older than 18 years in sub-adults using tooth tissue volumes from MRI segmentation of the entire 1st and 2nd molars, and to establish a model for combining information from two different molars. MATERIALS AND METHODS: We acquired T2 weighted MRIs of 99 volunteers with a 1.5-T scanner. Segmentation was performed using SliceOmatic (Tomovision©). Linear regression was used to analyse the association between mathematical transformation outcomes of tissue volumes, age, and sex. Performance of different outcomes and tooth combinations were assessed based on the p-value of the age variable, common, or separate for each sex, depending on the selected model. The predictive probability of being older than 18 years was obtained by a Bayesian approach using information from the 1st and 2nd molars both separately and combined. RESULTS: 1st molars from 87 participants, and 2nd molars from 93 participants were included. The age range was 14-24 years with a median age of 18 years. The transformation outcome (high signal soft tissue + low signal soft tissue)/total had the strongest statistical association with age for the lower right 1st (p= 7.1*10-4 for males) and 2nd molar (p=9.44×10-7 for males and p=7.4×10-10 for females). Combining the lower right 1st and 2nd molar in males did not increase the prediction performance compared to using the best tooth alone. CONCLUSION: MRI segmentation of the lower right 1st and 2nd molar might prove useful in the prediction of age older than 18 years in sub-adults. We provided a statistical framework to combine the information from two molars.

Age prediction in sub-adults based on MRI segmentation of 3rd molar tissue volumes.

PURPOSE: Our aim was to investigate tissue volumes measured by MRI segmentation of the entire 3rd molar for prediction of a sub-adult being older than 18 years. MATERIAL AND METHOD: We used a 1.5-T MR scanner with a customized high-resolution single T2 sequence acquisition with 0.37 mm iso-voxels. Two dental cotton rolls drawn with water stabilized the bite and delineated teeth from oral air. Segmentation of the different tooth tissue volumes was performed using SliceOmatic (Tomovision©). Linear regression was used to analyze the association between mathematical transformation outcomes of the tissue volumes, age, and sex. Performance of different transformation outcomes and tooth combinations were assessed based on the p value of the age variable, combined or separated for each sex depending on the selected model. The predictive probability of being older than 18 years was obtained by a Bayesian approach. RESULTS: We included 67 volunteers (F/M: 45/22), range 14-24 years, median age 18 years. The transformation outcome (pulp + predentine)/total volume for upper 3rd molars had the strongest association with age (p = 3.4 × 10-9). CONCLUSION: MRI segmentation of tooth tissue volumes might prove useful in the prediction of age older than 18 years in sub-adults.

Successful treatment with repeated dexamethasone implant injections for recurrent macular edema after acute retinal necrosis.

BACKGROUND: The treatment of recurrent cystoid macular edema associated with acute retinal necrosis is challenging due to the concern that treatment with intravitreal steroids may reactivate the retinitis. CASE REPORT: An immunocompetent patient diagnosed with acute retinal necrosis was treated with oral valacyclovir and intravitreal injections of foscarnet. Giant tears in her retina necessitated a vitrectomy with silicone oil. She developed cystoid macular edema after the removal of the silicone oil. The edema responded to high-dose prednisolone but recurred when the dose was tapered to 20 mg daily. Under close surveillance and increased antiviral medication, she was treated with a dexamethasone implant with complete resolution of the edema. Unfortunately, the edema recurred, and the treatment had to be repeated. Over 18 months, she received five dexamethasone implants without recurrence of the viral retinitis. CONCLUSIONS: This case shows successful treatment of recurring cystoid macular edema following acute retinal necrosis with repeated intravitreal dexamethasone implants in a patient receiving valacyclovir maintenance treatment.

Validating the screening criteria for bone metastases in treatment-naïve unfavorable intermediate and high-risk prostate cancer - the prevalence and location of bone- and lymph node metastases.

OBJECTIVE: The European Association of Urology (EAU) recommends a bone scan for newly diagnosed unfavorable intermediate- and high-risk prostate cancer. We aimed to validate the screening criteria for bone metastases in patients with treatment-naïve prostate cancer. METHODS: This single-center retrospective study included all patients with treatment-naïve unfavorable intermediate- or high-risk prostate cancer. All underwent MRI of the lumbar column (T2Dixon) and pelvis (3DT2w, DWI, and T2 Dixon). The presence and location of lymph node and bone metastases were registered according to risk groups and radiological (rad) T-stage. The risk of lymph node metastases was assessed by odds ratio (OR). RESULTS: We included 390 patients, of which 68% were high-risk and 32% were unfavorable intermediate-risk. In the high-risk group, the rate of regional- and non-regional lymph node metastases was 11% and 6%, respectively, and the rate of bone metastases was 10%. In the unfavorable intermediate-risk group, the rate of regional- and non-regional lymph node metastases was 4% and 0.8%, respectively, and the rate of bone metastases was 0.8%. Metastases occurred exclusively in the lumbar column in 0.5% of all patients, in the pelvis in 4%, and the pelvis and lumbar column in 3%. All patients with bone metastases had radT3-4, and patients with radT3-4 showed a four-fold increased risk of lymph node metastases (OR 4.48, 95% CI: 2.1-9.5). CONCLUSION: Bone metastases were found in 10% with high-risk prostate cancer and 0.8% with unfavorable intermediate-risk. Therefore, we question the recommendation to screen the unfavorable intermediate-risk group for bone metastases. KEY POINTS: • The rate of bone metastases was 10% in high-risk patients and 0.8% in the unfavorable intermediate-risk group. • The rate of lymph-node metastases was 17% in high-risk patients and 5% in the unfavorable intermediate-risk group. • No bone metastases were seen in radiologically localized disease.

Predictive Performance of Prospectively Applied ISUP and Fuhrman Grade in Nonmetastatic Renal Cell Carcinoma.

BACKGROUND/AIM: In 2012, the International Society of Urological Pathology (ISUP) recommended replacing Fuhrman with ISUP for grading renal cell carcinoma (RCC). Our aim was to report recurrence-free survival (RFS) and assess prognostic value of ISUP and Fuhrman for predicting recurrence using original pathology assessment and routine follow-up data. PATIENTS AND METHODS: In this single-institution retrospective cohort study, 686 patients underwent a single session total or partial nephrectomy due to nonmetastatic RCC (nmRCC). Of those, 564 had tumors prospectively graded according to either ISUP or Fuhrman, which defined the cohorts. RFS was defined as the interval from surgery to local recurrence and/or metastasis. Differences in RFS were calculated with log rank test. Cox models adjusted for risk factors were used for predicting recurrence. RESULTS: During a median follow-up of 36 months in the ISUP group (n=152), 11% developed recurrent disease. RFS was significantly lower for grade 4 compared to 1-3 (p<0.001), but non-significant between 1-3. Grade was the only significant predictor in multivariate analyses. During a median follow-up time of 50 months in the Fuhrman group (n=412), 16% developed recurrent disease. There was a significant difference in RFS between grades 2 and 3 (p=0.003) and between 3 and 4 (p<0.001), but non-significant between 1 and 2 (p=0.063). Grade, positive surgical margin, tumor size ≥4 cm, and pT were significant predictors of recurrence in multivariate analyses. CONCLUSION: ISUP grading alone is an accurate tool for predicting recurrence in patients with nmRCC.

Quantification of adipose tissues by Dual-Energy X-Ray Absorptiometry and Computed Tomography in colorectal cancer patients.

BACKGROUND & AIMS: Excess adipose tissue may affect colorectal cancer (CRC) patients' disease progression and treatment. In contrast to the commonly used anthropometric measurements, Dual-Energy X-Ray Absorptiometry (DXA) and Computed Tomography (CT) can differentiate adipose tissues. However, these modalities are rarely used in the clinic despite providing high-quality estimates. This study aimed to compare DXA's measurement of abdominal visceral adipose tissue (VAT) and fat mass (FM) against a corresponding volume by CT in a CRC population. Secondly, we aimed to identify the best single lumbar CT slice for abdominal VAT. Lastly, we investigated the associations between anthropometric measurements and VAT estimated by DXA and CT. METHODS: Non-metastatic CRC patients between 50-80 years from the ongoing randomized controlled trial CRC-NORDIET were included in this cross-sectional study. Corresponding abdominal volumes were acquired by Lunar iDXA and from clinically acquired CT examinations. Also, single CT slices at L2-, L3-and L4-level were obtained. Agreement between the methods was investigated using univariate linear regression and Bland-Altman plots. RESULTS: Sixty-six CRC patients were included. Abdominal volumetric VAT and FM measured by DXA explained up to 91% and 96% of the variance in VAT and FM by CT, respectively. Bland-Altman plots demonstrated an overestimation of VAT by DXA compared to CT (mean difference of 76 cm3) concurrent with an underestimation of FM (mean difference of -319 cm3). A higher overestimation of VAT (p = 0.015) and underestimation of FM (p = 0.036) were observed in obese relative to normal weight subjects. VAT in a single slice at L3-level showed the highest explained variance against CT volume (R2 = 0.97), but a combination of three slices (L2, L3, L4) explained a significantly higher variance than L3 alone (R2 = 0.98, p < 0.006). The anthropometric measurements explained between 31-65% of the variance of volumetric VAT measured by DXA and CT. CONCLUSIONS: DXA and the combined use of three CT slices (L2-L4) are valid to predict abdominal volumetric VAT and FM in CRC patients when using volumetric CT as a reference method. Due to the poor performance of anthropometric measurements we recommend exploring the added value of advanced body composition by DXA and CT integrated into CRC care.

Multicenter transperineal MRI-TRUS fusion guided outpatient clinic prostate biopsies under local anesthesia.

INTRODUCTION: Transperineal Prostate biopsies (TPBx) are usually performed under general anesthesia without image fusion. This study aimed to evaluate prostate cancer (Pca) detection rates (CDR), pain, and adverse events using a novel, free-hand TPBx technique, based on elastic fusion of magnetic resonance imaging (MRI) and transrectal ultrasound (TRUS) under local anesthesia. MATERIALS AND METHODS: This multicenter retrospective study included all consecutive patients scheduled for a TPBx. All had clinical suspicion of Pca, active surveillance scheduled for a re-biopsy, or suspicion of local recurrence after previous treatment. Bi-parametric or multiparametric MRI was performed in all patients and classified as positive in the case of Prostate Imaging-Reporting and Data System (PIRADS) suspicion ≥3. At least 1 targeted TPBx was realized from each PIRADS ≥3 index lesion. Six to 12 systematic random TPBx were done in patients with negative MRI. All biopsies were performed under local anesthesia in an outpatient clinic with MRI-TRUS fusion and the 3D navigation system Trinity Perine (Koelis, France). Any- and clinically significant Pca (csPca) (ISUP gr. ≥2) was recorded. Biopsy-related pain and adverse events were reported according to a visual analogue score of 0-10. RESULTS: In total, 377 patients were included for analyses. The mean age was 67 years (95% Confidence Interval: 66-68) and the median prostate-specific antigen was 7.2 ng/ml (interquartile range [IQR] 4.8-11.0). MRI was negative in 6% and positive in 94%. The median MRI prostate volume was 43 ml (IQR 31-60) and the median MRI index tumor volume was 0.9 ml (IQR 0.5-2.1). The median number of TPBx was 4 (IQR 3-4). The overall detection of any- and csPca was 64% and 52%, respectively. The overall CDR according to PIRADS 3, 4, and 5 was 30%, 70%, and 94%, respectively. In patients with negative MRI, any- and csPca was detected in 23% and 9%, respectively. The median visual analogue score score was 2 (IQR 1-3, range 0-7). Two patients (0.5%) developed postbiopsy infection, of which one developed urosepsis. Treatment requiring haematuria or urinary retention did not occur. CONCLUSION: Free-hand MRI/TRUS fusion-guided and systematic random TPBx in LA is a feasible, safe, and well-tolerated technique for diagnosing Pca.

Should calculation of chemotherapy dosage for bowel cancer be based on body composition? / Bør beregning av cellegiftdose ved tarmkreft baseres på kroppssammensetning?

BACKGROUND: Dosage of chemotherapy for colon cancer is currently based on the patient's body surface area. Several studies have identified an association between low fat-free mass and chemotherapy toxicity among patients with metastatic colorectal cancer. This has been less widely studied for localised disease. This review aims to summarise studies that have investigated the association between clinical signs of disease-related malnutrition (low body mass index, weight loss and low muscle mass) and tolerance of chemotherapy in patients with localised colon cancer. MATERIAL AND METHOD: We conducted a systematic search in PubMed with various synonyms of the terms 'colorectal cancer', 'adjuvant chemotherapy', 'nutritional status' and 'toxicity'. The search was concluded in May 2019. Of 553 articles, 39 were considered relevant and read in full text. Ten of these fulfilled the inclusion criteria for this review. RESULTS: Nine of the ten studies indicate an association between clinical signs of disease-related malnutrition and dose-limiting toxicity. The association appears to be especially pronounced in patients with low fat-free mass. INTERPRETATION: The results support the hypothesis that there is an association between disease-related malnutrition and the prevalence of toxicity and modification of the course of adjuvant chemotherapy in patients with localised colon cancer. The potential benefits of basing chemotherapy dosage on body composition in addition to body surface area should be investigated in clinical trials.

Examining the upper urinary tract in patients with hematuria-time to revise the CT urography protocol?

BACKGROUND: Three-phase CT urography (CTU) is the gold standard for evaluating the upper urinary tract in patients with hematuria. We aimed to evaluate the accuracy of CTU for detecting upper urothelial cell carcinomas (UCC) in patients with hematuria and negative cystoscopy. Secondly, we aimed to determine the tumor visibility on each CTU phase. MATERIAL AND METHODS: This retrospective study included all patients with hematuria referred to CTU after a negative cystoscopy during 2016 and 2017. The original CTU reports were dichotomized as negative or positive. All patient charts were reviewed after a minimum of 18-month follow-up in order to register missed cancers. The results of biopsies and clinical follow-up were used as the reference standard. Two reviewers retrospectively evaluated the tumor visibility of each CT sequence in all true-positive CTUs. RESULTS: We included 376 patients with hematuria who underwent CTU after a negative cystoscopy. Macroscopic and microscopic hematuria occurred in 87% (327) and 13% (49), respectively. The incidence of upper urothelial cell carcinoma was 1.9% (7), and the sensitivity of CTU was 100% (95% CI, 59-100), specificity was 99% (95% CI, 98-100), positive predictive value was 88% (95% CI, 47-99), and negative predictive value was 100% (95% CI, 99-100). The accuracy was 99% (95% CI, 90-100). All UCCs were visible on the nephrographic phase for both reviewers. CONCLUSION: CTU is highly accurate for detecting upper UCCs. All cases were seen on the nephrographic phase. This suggests that the CTU protocol can be simplified. KEY POINTS: • CT urography is highly accurate for detecting upper urothelial cell carcinomas. • All cancers were seen on the nephrographic phase. • All cancers were detected in patients with macroscopic hematuria.

Elevated d-dimer cut-off values for computed tomography pulmonary angiography-d-dimer correlates with location of embolism.

BACKGROUND: Acute pulmonary embolism (APE) is a potentially fatal condition, and making a timely diagnosis can be challenging. Computed tomography pulmonary angiography (CTPA) has become the modality of choice, and this contributes to the increasing load on emergency room CT scanners. Our purpose was to investigate whether an elevated d-dimer cut-off could reduce the demand for CTPA while maintaining a high sensitivity and negative predictive value (NPV). METHODS: We retrospectively reviewed all patients referred for CTPA with suspicion of APE in 2012, and collected d-dimer values and CTPA results. We investigated the diagnostic performance of d-dimer using a 0.5 mg/L cut-off and an age adjusted cut-off. We also evaluated a new and elevated cut-off. Cases were categorized according to their CTPA result into: no embolism, peripheral embolism, lobar embolism and central embolism. Finally we investigated a possible correlation between d-dimer values and location of embolism. RESULTS: We included 1,051 CTPAs, from which 216 (21%) showed pulmonary embolism. There were concomitant d-dimer analyses in 822 CTPA examinations. The current 0.5 mg/L cut-off achieved a sensitivity and NPV of 99%. The age-adjusted cut-off achieved a sensitivity and NPV of 98%, and our suggested cut-off of 0.9 mg/L achieved a sensitivity and NPV of 97%. CONCLUSIONS: We conclude that the elevated d-dimer cut-off of 0.9 mg/L achieved a high sensitivity and NPV, while reducing the number of CTPA by 27%. The correlation between d-dimer values and location of embolisms supports the suggestion of an elevated d-dimer value.

Radiologist-initiated double reading of abdominal CT: retrospective analysis of the clinical importance of changes to radiology reports.

BACKGROUND: Misinterpretation of radiological examinations is an important contributing factor to diagnostic errors. Consultant radiologists in Norwegian hospitals frequently request second reads by colleagues in real time. Our objective was to estimate the frequency of clinically important changes to radiology reports produced by these prospectively obtained double readings. METHODS: We retrospectively compared the preliminary and final reports from 1071 consecutive double-read abdominal CT examinations of surgical patients at five public hospitals in Norway. Experienced gastrointestinal surgeons rated the clinical importance of changes from the preliminary to final report. The severity of the radiological findings in clinically important changes was classified as increased, unchanged or decreased. RESULTS: Changes were classified as clinically important in 146 of 1071 reports (14%). Changes to 3 reports (0.3%) were critical (demanding immediate action), 35 (3%) were major (implying a change in treatment) and 108 (10%) were intermediate (requiring further investigations). The severity of the radiological findings was increased in 118 (81%) of the clinically important changes. Important changes were made less frequently when abdominal radiologists were first readers, more frequently when they were second readers, and more frequently to urgent examinations. CONCLUSION: A 14% rate of clinically important changes made during double reading may justify quality assurance of radiological interpretation. Using expert second readers and a targeted selection of urgent cases and radiologists reading outside their specialty may increase the yield of discrepant cases.