Follow-up of acute pyelonephritis: what causes the diffusion-weighted magnetic resonance imaging recovery to lag clinical recovery?

PURPOSE: To analyze with diffusion-weighted magnetic resonance imaging (DW-MRI) the evolution and progress to resolution of acute pyelonephritis (APN) foci over a period of 3 months after onset. METHODS: 30 women (age 22-51 years) with clinical, laboratory (white blood cell and C-reactive protein), and DW-MRI (4b-values 0, 50, 600, 1000 s/mm2) diagnosis of APN were prospectively enrolled. Two double-blinded radiologists evaluated the number of APN foci, and for each of them dimension (D), absolute diffusion coefficient (ADC), and its ratio R to the ADC of unaffected parenchyma. Signature of radiological recovery was focus no longer visible (DW-) and ADC of its site not inferior to the ADC of the unaffected parenchyma, i.e., R ≥ 0.9. Clinical and DW-MRI follow-ups (FU) were performed at 1 and 3 months. RESULTS: At the acute stage (t 0), 187 APN foci were found, with ADC0 = 1.3 ± 0.2 × 10-3 mm2/s, R 0 = 0.65 ± 0.12, and D 0 = 14 ± 7.5 mm. By the 1-month FU (t 1), all patients had no symptoms and physiological laboratory values; despite this, only 80 (43%) foci were solved, increasing to 138 (74%) by at the 3-month FU. The ROC curve (AUC ≥ 0.80) identified R 0 ≤ 0.6 and D 0 > 15 mm as forecast of slow radiologic resolution. About 80% of foci unsolved at 1 month but with R 1 ≥ 0.8 and D 1 ≤ 10 mm reached solution at 3 months. CONCLUSIONS: DW-MRI recovery of APN foci does not always coincide with clinical recovery. The evolution of an APN focus is shaped by its initial values R 0 and D 0. About half of the foci still visible at 1 month reached radiological resolution in the two following months.

Comparing CT colonography and flexible sigmoidoscopy: a randomised trial within a population-based screening programme.

IMPORTANCE AND AIMS: The role of CT colonography (CTC) as a colorectal cancer (CRC) screening test is uncertain. The aim of our trial was to compare participation and detection rate (DR) with sigmoidoscopy (flexible sigmoidoscopy (FS)) and CTC in a screening setting. DESIGN SETTING AND PARTICIPANTS: We conducted two randomised clinical trials (RCTs). (1) Participation RCT: individuals, aged 58 years, living in Turin (Italy), were randomly assigned to be invited to FS or CTC screening; (2) detection RCT: residents in northern Italy, aged 58-60, giving their consent to recruitment, were randomly allocated to CTC or FS. Polyps ≥6 mm at CTC, or 'high-risk' distal lesions at FS, were referred for colonoscopy (TC). MAIN OUTCOME MEASURES: Participation rate (proportion of invitees examined); DR of advanced adenomas or CRC (advanced neoplasia (AN)). RESULTS: Participation was 30.4% (298/980) for CTC and 27.4% (267/976) for FS (relative risk (RR) 1.1; 95% CI 0.98 to 1.29). Among men, participation was higher with CTC than with FS (34.1% vs 26.5%, p=0.011). In the detection RCT, 2673 subjects had FS and 2595 had CTC: the AN DR was 4.8% (127/2673, including 9 CRCs) with FS and 5.1% (133/2595, including 10 CRCs) with CTC (RR 1.08; 95% CI 0.85 to 1.37). Distal AN DR was 3.9% (109/2673) with FS and 2.9% (76/2595) with CTC (RR 0.72; 95% CI 0.54 to 0.96); proximal AN DR was 1.2% (34/2595) for FS vs 2.7% (69/2595) for CTC (RR 2.06; 95% CI 1.37 to 3.10). CONCLUSIONS AND RELEVANCE: Participation and DR for FS and CTC were comparable. AN DR was twice as high in the proximal colon and lower in the distal colon with CTC than with FS. Men were more likely to participate in CTC screening. TRIAL REGISTRATION NUMBER: NCT01739608; Pre-results.

Acute pyelonephritis in transplanted kidneys: can diffusion-weighted magnetic resonance imaging be useful for diagnosis and follow-up?

PURPOSE: To assess reliability of diffusion-weighted magnetic resonance imaging (DW-MRI) in the management of acute pyelonephritis (APN) foci in transplanted kidneys. MATERIALS AND METHODS: In the 2012-2014 period, 24 kidney-transplanted patients underwent MR screening for clinical suspicion of APN. Two readers independently analyzed all images, establishing presence and location of APN foci. The 22 patients who were positive at the MR exam constituted the study population. For each patient the apparent diffusion coefficient (ADC) was measured in the APN foci and in three sites of the healthy parenchyma (case-control comparison). The data were matched to the laboratory measurements for white blood cell, C-reactive protein, and serum creatinine. RESULTS: Forty-six APN foci were found in 22/24 patients. At the acute stage, the difference in ADC between healthy parenchyma and APN foci was significant (2.06 ± 0.16 vs. 1.43 ± 0.32 × 10(-3) mm(2)/s; p < 0.0001). The performance of ADC as APN indicator was tested by the receiving operating characteristics (ROC) curve: the area under curve AUC = 0.99 witnessed an excellent discriminatory ability, with threshold APN/normal parenchyma 1.9 × 10(-3) mm(2)/s. At the 1-month follow-up 43/46 APN foci were no longer visible, with ADC values significantly higher than at the acute stage; all laboratory data were physiological, with WBC significantly reduced from the acute phase (5.2 ± 1.6 × 10(9)/L vs. 10.6 ± 4.8 × 10(9)/L; p < 0.0001). The other 3 patients underwent further therapy and exams, including a third MR. CONCLUSIONS: DW-MRI with ADC measurement seems to be a reliable tool in diagnosing and monitoring APN foci in transplanted kidneys, with clinical impact on patient management.

Multiparametric Gd-EOB-DTPA magnetic resonance in diagnosis of HCC: dynamic study, hepatobiliary phase, and diffusion-weighted imaging compared to histology after orthotopic liver transplantation.

PURPOSE: To evaluate Gd-EOB-DTPA-enhanced magnetic resonance (MR) performance during dynamic (DYN) phases, hepatobiliary (HB) phase and diffusion-weighted imaging (DWI) compared with pathological findings in patients undergoing orthotopic liver transplantation (OLT) for hepatocellular carcinoma (HCC) associated with different conditions, such as stage of chronic liver disease, histological grading, nodule size, and occurrence of previous treatments. METHODS: Retrospective analysis of 64 nodules reported as HCC at pathological analysis on 28 explanted livers, examined about 3 months before OLT using a 1.5 T device and 16 channels array after intravenous GD-EOB-DTPA injection. Lesions features and hepatic functional values were recorded for each patient. Two radiologists performed in consensus the analysis of nodules on DYN, HB, and DWI. MR findings were compared with those of pathological anatomy. Diagnostic indicators were calculated for each technique. RESULTS: DYN and HB showed no statistically significant difference in sensitivity (88% and 98%, respectively), diagnostic accuracy (90.6% and 99.9%), and specificity (both 100%), for all Child-Pugh scores, gradings, sizes, and presence or absence of previous treatments. DWI had a statistically significant lower sensitivity compared to DYN (p = 0.001) and HB (p < 0.0001); its sensitivity was significantly inferior for Child-Pugh Class B nodules than for Child-Pugh Class A ones (p = 0.00005). DWI sensitivity presented a significant increase (p = 0.03) with grading and presence of previous treatments (p = 0.0006). ADC values showed no statistically significant changes with Child-Pugh score, grading and nodules size; statistically significant increase was instead found for treated vs. untreated nodules (p = 0.016). CONCLUSIONS: In a multiparametric HCC MRI assessment, DYN and HB play the leading role, with DWI faring acceptably well for Child-Pugh Class A nodules and treated ones.

Diffusion-weighted imaging and apparent diffusion coefficient values versus contrast-enhanced MR imaging in the identification and characterisation of acute pyelonephritis.

OBJECTIVE: To compare contrast-enhanced (CEMR) and diffusion-weighted (DWI) magnetic resonance imaging in diagnosing acute pyelonephritis (APN) and to assess ADC measurement reliability in differentiating among normal renal parenchyma, APN and abscesses. METHODS: Eighty-eight patients (80 women, mean age 36.5 years) with clinical suspicion of APN were retrospectively reviewed. An experienced observer quantified lesions with a score ranging from 0 to 3. DWI and CEMR were compared on the basis of the assigned score, total examination number (88) and on presence (36)/absence (52) of abscesses. ADC values, calculated at the healthy parenchyma, APN and abscessed were compared to each other. RESULTS: Agreement between CEMR and DWI was 94.3 % (83/88 patients; P < 0.05). In the APN group, DWI was awarded the highest visibility score compared to CEMR (P = 0.05), while in the abscess group CEMR had the highest score (P = 0.04). The difference between ADC values of the APN-healthy parenchyma and abscess-APN groups was significant (P < 0.05). The area under the ROC curve of ADC values of the APN-healthy and abscess-APN groups were found to be 0.94 (95 % CI; cutoff value = 2) and 0.78 (95 % CI; cutoff value = 1.2) respectively. CONCLUSIONS: Diffusion-weighted imaging appears reliable in the diagnosis and follow-up of acute pyelonephritis and could provide a reasonable alternative to contrast-enhanced magnetic resonance imaging.

Efficacy of computer-aided detection as a second reader for 6-9-mm lesions at CT colonography: multicenter prospective trial.

PURPOSE: To assess the effect of computer-aided detection (CAD) as a second reader on the sensitivity and specificity of computed tomographic (CT) colonography in detecting 6-9-mm colorectal cancer (CRC) lesions. MATERIALS AND METHODS: Individuals with clinical indications for colonoscopy--either for symptoms or as part of participating in a surveillance program or CRC screening--were prospectively enrolled at one of 10 academic centers between July 2007 and May 2009. Institutional review board approval was obtained at each clinical site, and all participants provided written informed consent. All participants underwent CT colonography and colonoscopy on the same day. Experienced readers interpreted the CT colonography images unassisted and then reviewed all colorectal lesion-like structures pinpointed by the CAD algorithm. Segmental unblinding of CT colonoscopy findings at colonoscopy was utilized. The sensitivity and specificity of unassisted and CAD-assisted reading in identifying individuals with 6-9-mm lesions were calculated and compared by means of pairwise analysis. RESULTS: A total of 618 participants (mean age, 57.9 years; 54.5% male) were included in the final analysis. Of these participants, 464 (75.1%) had no lesions 6 mm or larger, and 52 (8.4%) had 6-9-mm lesions. The sensitivity of CT colonography with unassisted reading and that with CAD-assisted reading in identifying individuals with 6-9-mm lesions was 65.4% (95% confidence interval [CI]: 50.9%, 78.0%) and 76.9% (95% CI: 63.2%, 87.5%; P = .016), respectively. No significant change in specificity was observed: The specificity of CT colonography with unassisted and that with CAD-assisted reading was 91.8% (95% CI: 88.9%, 94.1%) and 90.9% (95% CI: 88.0%, 93.4%; P = .063), respectively. Evaluation of CAD candidates required an additional 1.6 minutes (25th-75th percentile: 1.0 minute to 3.4 minutes). CONCLUSION: The addition of CAD to reading performed by experienced readers resulted in a significant benefit in the detection of 6-9-mm polyps at CT colonography in this cohort. SUPPLEMENTAL MATERIAL: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.12120376/-/DC1.

Emerging treatment options in the management of non-small cell lung cancer.

Lung cancer (LC) has become the leading cancer-related cause of death in the US and in developed European countries in the last decade. Its incidence is still growing in females and in smokers. Surgery remains the treatment of choice whenever feasible, but unfortunately, many patients have an advanced LC at presentation and one-third of potentially operable patients do not receive a tumor resection because of their low compliance for intervention due to their compromised cardiopulmonary functions and other comorbidities. For these patients the alternative therapeutic options are stereotactic radiotherapy or percutaneous radiofrequency. When surgery is planned, an anatomical resection (segmentectomy, lobectomy, bilobectomy, pneumonectomy, sleeve lobectomy) is usually performed; wedge resection (considered as a nonanatomical one) is generally the accepted option for unfit patients. The recent increase in discovering small and peripheral LCs and/or ground-glass opacities with screening programs has dramatically increased surgeons' interest in limited resections. The role of these resections is discussed. Also, recent improvements in molecular biology techniques have increased the chemotherapic options for neoadjuvant LC treatment. The role and the importance of targeted chemotherapy is also discussed.

Diagnostic accuracy of computed tomographic colonography for the detection of advanced neoplasia in individuals at increased risk of colorectal cancer.

CONTEXT: Computed tomographic (CT) colonography has been recognized as an alternative for colorectal cancer (CRC) screening in average-risk individuals, but less information is available on its performance in individuals at increased risk of CRC. OBJECTIVE: To assess the accuracy of CT colonography in detecting advanced colorectal neoplasia in asymptomatic individuals at increased risk of CRC using unblinded colonoscopy as the reference standard. DESIGN, SETTING, AND PARTICIPANTS: This was a multicenter, cross-sectional study. Individuals at increased risk of CRC due to either family history of advanced neoplasia in first-degree relatives, personal history of colorectal adenomas, or positive results from fecal occult blood tests (FOBTs) were recruited in 11 Italian centers and 1 Belgian center between December 2004 and May 2007. Each participant underwent CT colonography followed by colonoscopy on the same day. MAIN OUTCOME MEASURES: Sensitivity and specificity of CT colonography in detecting individuals with advanced neoplasia (ie, advanced adenoma or CRC) 6 mm or larger. RESULTS: Of 1103 participants, 937 were included in the final analysis: 373 cases in the family-history group, 343 in the group with personal history of adenomas, and 221 in the FOBT-positive group. Overall, CT colonography identified 151 of 177 participants with advanced neoplasia 6 mm or larger (sensitivity, 85.3%; 95% confidence interval [CI], 79.0%-90.0%) and correctly classified results as negative for 667 of 760 participants without such lesions (specificity, 87.8%; 95% CI, 85.2%-90.0%). The positive and negative predictive values were 61.9% (95% CI, 55.4%-68.0%) and 96.3% (95% CI, 94.6%-97.5%), respectively; after group stratification, a significantly lower negative predictive value was found for the FOBT-positive group (84.9%; 95% CI, 76.2%-91.3%; P < .001). CONCLUSIONS: In a group of persons at increased risk for CRC, CT colonography compared with colonoscopy resulted in a negative predictive value of 96.3% overall. When limited to FOBT-positive persons, the negative predictive value was 84.9%.