Quality assessment of prostate MRI by PI-QUAL score: Inter-reader agreement and impact on prostate cancer local staging at 3 Tesla.

PURPOSE: To evaluate whether the Prostate Imaging Quality (PI-QUAL) score impacts prostate cancer (PCa) staging on MRI. The secondary goal was to test inter-reader agreement among radiologists experienced in prostate imaging. METHOD: A retrospective, single-center study with patients who underwent 3 Tesla prostate MRI scans and were submitted to radical prostatectomy (RP) between January 2018 and November 2021 and were eligible for our study. Extraprostatic extension (EPE) data were collected from original MR reports (EPEm) and pathological reports of RP specimens (EPEp). Three expert prostate radiologists (ESUR/ESUI criteria R1, R2, R3) independently evaluated all MRI exams according to PI-QUAL score for image quality (1 to 5; 1: poor, 5: excellent), blinded to original imaging reports and clinical data. We studied the diagnostic performance of MRI using pooled data from PI-QUAL scores (≤3 vs. ≥4). We also performed univariate and multivariate analyses to assess the PI-QUAL score impact on local PCa staging. Cohen's K and Tau-b Kendall tests were used to assess the inter-reader agreement for PI-QUAL score, T2WI, DWI, and DCE. RESULTS: Our final cohort included 146 patients, of which 27.4% presented EPE on pathology. We observed no impact of imaging quality on accuracy for EPE prediction: AUC of 0.750 (95% CI 0.26-1) for PI-QUAL ≤ 3 and 0.705 (95% CI 0.618-0.793) for PI-QUAL ≥ 4. The multivariate analysis demonstrated a correlation of EPEm (OR 3.25, p 0.001) and ISUP grade group (OR 1.89, p 0.012) to predict EPEp. The inter-reader agreement was moderate to substantial (0.539 for R1-R2, 0.522 for R2-R3, and 0.694 for R1-R3). CONCLUSION: Our clinical impact evaluation showed no direct correlation between MRI quality by PI-QUAL score and accuracy in detecting EPE in patients undergoing RP. Additionally, we had moderate to a substantial inter-reader agreement for the PI-QUAL score.

Prostate imaging features on magnetic resonance imaging of young patients.

OBJECTIVE: To identify magnetic resonance imaging findings of the prostate in young adults, including symptomatic and asymptomatic patients. The aim of this study is to evaluate the main aspects of prostate imaging in young patients. METHODS: A total of 102 patients under 40 years of age, who underwent prostate magnetic resonance imaging between January 2016 and January 2019, were included in this study. The patients were divided into two groups: symptomatic for prostatitis (Group 1) and asymptomatic (Group 2). Magnetic resonance imaging scans were anonymized and interpreted by a radiologist blinded for clinical information. The study evaluated peripheral zone signal in T2-weighted sequences, diffusion and apparent diffusion coefficient map; peripheral zone enhancement pattern; seminal vesicles and periprostatic fat. RESULTS: All evaluated criteria did not present statistically significant differences between the two groups. The most common pattern was heterogeneous hyposignal on T2 (57.9% in Group 1 and 57.8% in Group 2; p=0.506), mild diffuse / wedge-shaped areas of hypointensity on apparent diffusion coefficient map (61.4% in Group 1 and 64.4% in Group 2; p=0.931) and early post-contrast enhancement (73.7% in Group 1 and 68.9% in Group 2, p=0719). CONCLUSION: The magnetic resonance imaging aspect of young patients showed no differences between symptomatic and asymptomatic patients.

T2-weighted imaging hypointensity in an ovarian lesion: is it a benign finding?

OBJECTIVE: To evaluate whether the presence of a hypointense signal at T2-weighted imaging in a solid ovarian lesion on magnetic resonance imaging is a predictor of stability and benignity. METHODS: This is a single center study, prospectively read with retrospective acquired data. The database was searched for patients who underwent magnetic resonance imaging between January 2008 and October 2019 and whose reports mentioned solid ovarian lesions with low signal on T2-weighted imaging. A total of 47 nodules were included. A radiologist who was blinded to the clinical indication for magnetic resonance imaging and original reports evaluated the cases. Objective and subjective criteria of ovarian lesions in magnetic resonance imaging were evaluated. RESULTS: Thirty-five nodules were considered benign/stable and 12 were considered non-stable. The analysis showed that the non-stable lesions showed statistically more hyperintensity at T1-weighted imaging compared to the stable lesions. CONCLUSION: T2-weighted imaging hypointensity can be considered a predictor of stability in solid ovarian lesions when associated with iso/hypointensity in T1-weighted imaging.

Enhancement patterns of adrenal nodules on magnetic resonance imaging

ABSTRACT Objective: To compare enhancement patterns of typical adrenal adenomas, lipid-poor adenomas, and non-adenomas on magnetic resonance imaging (MRI). Materials and Methods: Evaluation of adrenal nodules larger than 1.0 cm, with at least 2-year follow-up, evaluated on MRI in January 2007 and December 2016. Two different protocols were included - upper abdomen MRI (delayed phase after 3 minutes) and abdomen and pelvis MRI (delayed phase after 7 minutes) - and nodules were divided in typical adenomas (characterized on out-of-phase MRI sequence), lipid-poor adenomas (based on follow-up imaging stability) and non-adenomas (based on pathological finding or follow-up imaging). T2-weighted and enhancement features were analyzed (absolute and relative washout and enhancement curve pattern), similarly to classic computed tomography equations. Results: Final cohort was composed of 123 nodules in 116 patients (mean diameter of 1.8 cm and mean follow up time of 4 years and 3 months). Of them, 98 (79%) nodules had features of typical adenomas by quantitative chemical shift imaging, and demonstrated type 3 curve pattern in 77%, mean absolute and relative washout of 29% and 16%, respectively. Size, oncologic history and T2-weighted features showed statistically significant differences among groups. Also, a threshold greater than 11.75% for absolute washout on MRI achieved sensitivity of 71.4% and specificity of 70.0%, in differentiating typical adenomas from non-adenomas. Conclusion: Calculating absolute washout of adrenal nodules on MRI may help identifying proportion of non-adenomas.

Enhancement patterns of adrenal nodules on magnetic resonance imaging.

OBJECTIVE: To compare enhancement patterns of typical adrenal adenomas, lipid-poor adenomas, and non-adenomas on magnetic resonance imaging (MRI). MATERIALS AND METHODS: Evaluation of adrenal nodules larger than 1.0 cm, with at least 2-year follow-up, evaluated on MRI in January 2007 and December 2016. Two different protocols were included - upper abdomen MRI (delayed phase after 3 minutes) and abdomen and pelvis MRI (delayed phase after 7 minutes) - and nodules were divided in typical adenomas (characterized on out-of-phase MRI sequence), lipid-poor adenomas (based on follow-up imaging stability) and non-adenomas (based on pathological finding or follow-up imaging). T2-weighted and enhancement features were analyzed (absolute and relative washout and enhancement curve pattern), similarly to classic computed tomography equations. RESULTS: Final cohort was composed of 123 nodules in 116 patients (mean diameter of 1.8 cm and mean follow up time of 4 years and 3 months). Of them, 98 (79%) nodules had features of typical adenomas by quantitative chemical shift imaging, and demonstrated type 3 curve pattern in 77%, mean absolute and relative washout of 29% and 16%, respectively. Size, oncologic history and T2-weighted features showed statistically significant differences among groups. Also, a threshold greater than 11.75% for absolute washout on MRI achieved sensitivity of 71.4% and specificity of 70.0%, in differentiating typical adenomas from non-adenomas. CONCLUSION: Calculating absolute washout of adrenal nodules on MRI may help identifying proportion of non-adenomas.

Prostate imaging features on magnetic resonance imaging of young patients

ABSTRACT Objective To identify magnetic resonance imaging findings of the prostate in young adults, including symptomatic and asymptomatic patients. The aim of this study is to evaluate the main aspects of prostate imaging in young patients. Methods A total of 102 patients under 40 years of age, who underwent prostate magnetic resonance imaging between January 2016 and January 2019, were included in this study. The patients were divided into two groups: symptomatic for prostatitis (Group 1) and asymptomatic (Group 2). Magnetic resonance imaging scans were anonymized and interpreted by a radiologist blinded for clinical information. The study evaluated peripheral zone signal in T2-weighted sequences, diffusion and apparent diffusion coefficient map; peripheral zone enhancement pattern; seminal vesicles and periprostatic fat. Results All evaluated criteria did not present statistically significant differences between the two groups. The most common pattern was heterogeneous hyposignal on T2 (57.9% in Group 1 and 57.8% in Group 2; p=0.506), mild diffuse / wedge-shaped areas of hypointensity on apparent diffusion coefficient map (61.4% in Group 1 and 64.4% in Group 2; p=0.931) and early post-contrast enhancement (73.7% in Group 1 and 68.9% in Group 2, p=0719). Conclusion The magnetic resonance imaging aspect of young patients showed no differences between symptomatic and asymptomatic patients.

T2-weighted imaging hypointensity in an ovarian lesion: is it a benign finding?

ABSTRACT Objective To evaluate whether the presence of a hypointense signal at T2-weighted imaging in a solid ovarian lesion on magnetic resonance imaging is a predictor of stability and benignity. Methods This is a single center study, prospectively read with retrospective acquired data. The database was searched for patients who underwent magnetic resonance imaging between January 2008 and October 2019 and whose reports mentioned solid ovarian lesions with low signal on T2-weighted imaging. A total of 47 nodules were included. A radiologist who was blinded to the clinical indication for magnetic resonance imaging and original reports evaluated the cases. Objective and subjective criteria of ovarian lesions in magnetic resonance imaging were evaluated. Results Thirty-five nodules were considered benign/stable and 12 were considered non-stable. The analysis showed that the non-stable lesions showed statistically more hyperintensity at T1-weighted imaging compared to the stable lesions. Conclusion T2-weighted imaging hypointensity can be considered a predictor of stability in solid ovarian lesions when associated with iso/hypointensity in T1-weighted imaging.

A comparative study of ultrasound and cross-sectional imaging for detection of small renal masses: anatomic factors and radiologist's experience.

OBJECTIVE: To evaluate anatomic factors and radiologist's experience in the detection of solid renal masses on ultrasonography. METHODS: We searched for solid renal masses diagnosed on cross-sectional imaging from 2007 to 2017 that also had previous ultrasonography from the past 6 months. The following features were evaluated: nodule size, laterality, location and growth pattern, patient body mass index and radiologist's experience in ultrasound. In surgically resected cases, pathologic reports were evaluated. Unpaired t test and χ2 test were used to evaluate differences among subgroups, using R-statistics. Statistical significance was set at p<0.05. RESULTS: The initial search of renal nodules on cross-sectional imaging resulted in 428 lesions and 266 lesions were excluded. Final cohort included 162 lesions and, of those, 108 (67%) were correctly detected on ultrasonography (Group 1) and 54 (33%) were missed (Group 2). Comparison of Groups 1 and 2 were as follows, respectively: body mass index (27.7 versus 27.1; p=0.496), size (2.58cm versus 1.74cm; p=0.003), laterality (54% versus 59% right sided; p=0.832), location (27% versus 22% upper pole; p=0.869), growth pattern (25% versus 28% endophytic; p=0.131) and radiologist's experience (p=0.300). From surgically resected cases, histology available for Group 1 was clear cell (n=11), papillary (n=15), chromophobe (n=2) renal cell carcinoma, oncocytoma (n=1), and, for Group 2, clear cell (n=7), papillary (n=5) renal cell carcinoma, oncocytoma (n=2), angiomyolipoma, chromophobe renal cell carcinoma, and interstitial pyelonephritis (n=1, each). CONCLUSION: Size was the only significant parameter related to renal nodule detection on ultrasound.

Prostate volume measurement by multiparametric magnetic resonance and transrectal ultrasound: comparison with surgical specimen weight.

OBJECTIVE: To assess accuracy of multiparametric magnetic resonance of the prostate to estimate gland volume, comparing the results with transrectal ultrasound and surgical specimen. METHODS: A retrospective study of 85 patients who underwent multiparametric magnetic resonance and transrectal ultrasound (for fusion image-guided biopsy) before radical prostatectomy. Prostate measurements were obtained from magnetic resonance axial and sagittal T2-weighted images and ultrasound; the prostate volume was determined using the ellipsoid formula. The results were compared with the surgical specimen weight. Maximum interval between multiparametric magnetic resonance imaging, transrectal ultrasound, and prostatectomy was 6 months. RESULTS: The prostate volume measured by multiparametric magnetic resonance imaging was 18-157cm3 (mean of 49.9cm3) and by transrectal ultrasound, 22-165cm3 (mean of 54.9cm3); the surgical specimen weight was 20-154g (mean of 48.6g), with no statistical differences. Based on the values obtained from imaging examinations, the prostate volume obtained was very close to the real prostatic weight, and the measures by multiparametric magnetic resonance were slightly more precise. CONCLUSION: Prostate volume measured by multiparametric magnetic resonance imaging and transrectal ultrasound showed similar values, and excellent agreement with real prostate weight of the surgical specimens. Prostate volume measured by magnetic resonance has been increasingly used in the clinical practice, and its value enables appropriate therapeutic planning and control of patients.

Can multiparametric magnetic resonance of the prostate avoid biopsies in patients with elevated PSA and surgical indication for benign prostatic enlargement?

INTRODUCTION: To evaluate the clinical dilemma of men with surgical indication due to benign prostatic enlargement (BPE) and concomitant elevated PSA, we analysed if multiparametric magnetic resonance imaging (mpMRI) could safely prescind the prostate biopsy. METHODS: Forty men with surgical indication due to BPE and concomitantly elevated PSA levels were prospectively enrolled and retrospectively analysed. All patients underwent 1.5 Tesla mpMRI prior to TRUS-guided biopsies. In cases where mpMRI was PIRADS 3 with focal lesions, PIRADS 4 or PIRADS 5, additional fragments were obtained with the fusion guided technique. Biopsy histopathological results were used as the standard of reference. Two scenarios were evaluated: scenario 1, considering mpMRI PIRADS 1 and 2 as negative; and scenario 2, considering PIRADS 1, 2 and 3 as negative. Clinically significant prostate cancer (CsPCa) was defined as ISUP ≥ 2. RESULTS: Median age was 68 years, median PSA was 9.41 (6.40-19.54) and median prostatic volume was 116.5 cc (IQR 86.5-155). Scenario 1 mpMRI sensitivity, specificity, PPV, NPV and accuracy for any prostate cancer on prostate biopsy was 76.9%, 63%, 50%, 85% and 67.5%. For csPCa, they were 87.5%, 59.4%, 35%, 95% and 65%, respectively, for the same measures. Scenario 2 the sensitivity, specificity, PPV, NPV and accuracy of mpMRI for any prostate cancer on prostate biopsy was 53.8%, 96.3%, 87.5%, 81.3% and 82.5%. For csPCa, they were 75%, 93.8%, 75%, 93.8% and 90%, respectively, for the same measures. CONCLUSION: Prostate mpMRI may prevent unnecessary biopsies in patients with elevated PSA and surgical indications due to BPE, given its high negative predictive value.

Prostate volume measurement by multiparametric magnetic resonance and transrectal ultrasound: comparison with surgical specimen weight / Avaliação do volume prostático obtido por ressonância magnética multiparamétrica da próstata e ultrassonografia transretal comparado ao peso da peça cirúrgica

ABSTRACT Objective To assess accuracy of multiparametric magnetic resonance of the prostate to estimate gland volume, comparing the results with transrectal ultrasound and surgical specimen. Methods A retrospective study of 85 patients who underwent multiparametric magnetic resonance and transrectal ultrasound (for fusion image-guided biopsy) before radical prostatectomy. Prostate measurements were obtained from magnetic resonance axial and sagittal T2-weighted images and ultrasound; the prostate volume was determined using the ellipsoid formula. The results were compared with the surgical specimen weight. Maximum interval between multiparametric magnetic resonance imaging, transrectal ultrasound, and prostatectomy was 6 months. Results The prostate volume measured by multiparametric magnetic resonance imaging was 18-157cm3 (mean of 49.9cm3) and by transrectal ultrasound, 22-165cm3 (mean of 54.9cm3); the surgical specimen weight was 20-154g (mean of 48.6g), with no statistical differences. Based on the values obtained from imaging examinations, the prostate volume obtained was very close to the real prostatic weight, and the measures by multiparametric magnetic resonance were slightly more precise. Conclusion Prostate volume measured by multiparametric magnetic resonance imaging and transrectal ultrasound showed similar values, and excellent agreement with real prostate weight of the surgical specimens. Prostate volume measured by magnetic resonance has been increasingly used in the clinical practice, and its value enables appropriate therapeutic planning and control of patients.

RESUMO Objetivo Avaliar a acurácia da ressonância magnética multiparamétrica da próstata para estimativa do volume da glândula, comparando seus resultados com a ultrassonografia transretal e correlacionando com o volume obtido da peça cirúrgica. Métodos Estudo retrospectivo incluindo 85 pacientes submetidos à ressonância magnética e, posteriormente, à ultrassonografia transretal (para orientação de biópsia com fusão de imagens) e, a seguir, à prostatectomia radical. As dimensões prostáticas foram obtidas na ressonância a partir das imagens nos planos axial e sagital em sequências ponderadas em T2 e, assim como na ultrassonografia, o volume foi calculado a partir do método da elipsoide. Os valores foram comparados com o peso prostático pós-cirúrgico. O intervalo máximo entre a ressonância e ultrassonografia e prostatectomia foi de 6 meses. Resultados O volume prostático obtido por ressonância magnética foi de 18 a 157cm3(média de 49,9cm3); pela ultrassonografia transretal, foi de 22 a 165cm3(média de 54,9cm3); e o peso da peça cirúrgica foi de 20 a 154g (média de 48,6g), sem diferenças estatísticas. A partir do valor obtido por esses métodos de imagem, provou-se que o volume prostático obtido aproximou-se bastante do peso real da próstata, com discreta maior precisão das medidas obtidas por ressonância magnética multiparamétrica. Conclusão As medidas do volume prostático adquiridas pela ressonância magnética e pela ultrassonografia transretal são semelhantes entre si, com excelente concordância com os pesos reais das próstatas obtidos das peças cirúrgicas. A avaliação desse dado, a partir da ressonância, método cada vez mais utilizado na prática clínica, permite o adequado planejamento terapêutico e o controle dos pacientes.

A comparative study of ultrasound and cross-sectional imaging for detection of small renal masses: anatomic factors and radiologists experience / Estudo comparativo de ultrassonografia e métodos seccionais para detecção de pequenas lesões renais: fatores anatômicos e experiência do radiologista

ABSTRACT Objective: To evaluate anatomic factors and radiologist's experience in the detection of solid renal masses on ultrasonography. Methods: We searched for solid renal masses diagnosed on cross-sectional imaging from 2007 to 2017 that also had previous ultrasonography from the past 6 months. The following features were evaluated: nodule size, laterality, location and growth pattern, patient body mass index and radiologist's experience in ultrasound. In surgically resected cases, pathologic reports were evaluated. Unpaired t test and χ2 test were used to evaluate differences among subgroups, using R-statistics. Statistical significance was set at p<0.05. Results: The initial search of renal nodules on cross-sectional imaging resulted in 428 lesions and 266 lesions were excluded. Final cohort included 162 lesions and, of those, 108 (67%) were correctly detected on ultrasonography (Group 1) and 54 (33%) were missed (Group 2). Comparison of Groups 1 and 2 were as follows, respectively: body mass index (27.7 versus 27.1; p=0.496), size (2.58cm versus 1.74cm; p=0.003), laterality (54% versus 59% right sided; p=0.832), location (27% versus 22% upper pole; p=0.869), growth pattern (25% versus 28% endophytic; p=0.131) and radiologist's experience (p=0.300). From surgically resected cases, histology available for Group 1 was clear cell (n=11), papillary (n=15), chromophobe (n=2) renal cell carcinoma, oncocytoma (n=1), and, for Group 2, clear cell (n=7), papillary (n=5) renal cell carcinoma, oncocytoma (n=2), angiomyolipoma, chromophobe renal cell carcinoma, and interstitial pyelonephritis (n=1, each). Conclusion: Size was the only significant parameter related to renal nodule detection on ultrasound.

RESUMO Objetivo: Avaliar os fatores anatômicos e a experiência do radiologista na detecção de massas renais sólidas na ultrassonografia. Métodos: Buscamos massas renais sólidas diagnosticadas em imagens seccionais, de 2007 a 2017, que também tivessem ultrassonografia prévia nos últimos 6 meses. As seguintes características foram avaliadas: tamanho do nódulo, lateralidade, localização e padrão de crescimento, índice de massa corporal do paciente e experiência do radiologista em ultrassonografia. Nos casos com ressecção cirúrgica, os laudos de patologia foram analisados. O teste t não pareado e o teste χ2 foram utilizados para avaliar as diferenças entre os subgrupos, usando R-statistics. A significância estatística foi estabelecida em p<0,05. Resultados: A pesquisa inicial de nódulos renais achados em imagens seccionais resultou em 428 lesões, com 266 exclusões. A coorte final incluiu 162 lesões e, destas, 108 (67%) foram detectadas corretamente na ultrassonografia (Grupo 1), e 54 (33%) não foram identificadas (Grupo 2). A comparação dos Grupos 1 e 2 mostrou índice de massa corporal (27,7 versus 27,1; p=0,496), tamanho (2,58cm versus 1,74cm; p=0,003), lateralidade (54% versus 59% no lado direito; p=0,832), localização (27% versus 22% no polo superior; p=0,869), padrão de crescimento (25% versus 28% endofítico; p=0,131) e experiência do radiologista (p=0,300). A histologia disponível para o Grupo 1 foi carcinoma renal de células claras (n=11), papilar (n=15), cromófobo (n=2), oncocitoma (n=1), e, para o Grupo 2, carcinoma renal de células claras (n=7), papilar (n=5), oncocitoma (n=2), angiomiolipoma, cromófobo e pielonefrite intersticial (n=1, cada). Conclusão: O tamanho foi o único parâmetro significativo relacionado à detecção de nódulos renais no ultrassom.

Common pitfalls in renal mass evaluation: a practical guide.

More than half of patients over 50 years of age have had at least one focal renal lesion detected as an incidental finding during an ultrasound, computed tomography, or magnetic resonance imaging examination. Although the majority of such lesions can be easily detected and correctly characterized, misdiagnoses may occur and are often related to methodological limitations, inappropriate imaging protocols, or misinterpretation. This pictorial essay provides recommendations on how to recognize benign and malignant renal processes that can be potentially missed or mischaracterized in imaging studies.

Mais da metade dos pacientes com mais de 50 anos de idade pode ter pelo menos uma lesão renal focal detectada de modo incidental em estudos de imagem, como ultrassonografia, tomografia computadorizada ou ressonância magnética. Embora a maioria dessas lesões possa ser facilmente caracterizada, erros de diagnóstico podem ocorrer e geralmente estão relacionados a limitações de métodos, protocolos de imagem inadequados e interpretação incorreta. Este ensaio iconográfico aborda recomendações sobre como reconhecer e interpretar lesões focais renais em estudos de imagem.

Common pitfalls in renal mass evaluation: a practical guide / Armadilhas comuns na avaliação da massa renal: um guia prático

Abstract More than half of patients over 50 years of age have had at least one focal renal lesion detected as an incidental finding during an ultrasound, computed tomography, or magnetic resonance imaging examination. Although the majority of such lesions can be easily detected and correctly characterized, misdiagnoses may occur and are often related to methodological limitations, inappropriate imaging protocols, or misinterpretation. This pictorial essay provides recommendations on how to recognize benign and malignant renal processes that can be potentially missed or mischaracterized in imaging studies.

Resumo Mais da metade dos pacientes com mais de 50 anos de idade pode ter pelo menos uma lesão renal focal detectada de modo incidental em estudos de imagem, como ultrassonografia, tomografia computadorizada ou ressonância magnética. Embora a maioria dessas lesões possa ser facilmente caracterizada, erros de diagnóstico podem ocorrer e geralmente estão relacionados a limitações de métodos, protocolos de imagem inadequados e interpretação incorreta. Este ensaio iconográfico aborda recomendações sobre como reconhecer e interpretar lesões focais renais em estudos de imagem.

Comparative study between monoexponential and biexponential diffusion weighted imaging sequences in multiparametric prostate magnetic resonance imaging.

OBJECTIVE: To compare qualitatively and quantitatively, in terms of image quality, a new biexponential diffusion sequence protocol with the standard monoexponential diffusion protocol on multiparametric prostate magnetic resonance imaging. METHODS: This study had a prospective data collection and cross-sectional analysis. Between August and November 2017, a total of 70 patients who underwent multiparametric prostate magnetic resonance imaging due to clinical suspicion of prostatic neoplasia were recruited. The images obtained were evaluated by two independent readers regarding subjective/qualitative criteria (six criteria) and objective/quantitative criteria (three criteria), always comparing the monoexponential to biexponential acquisition protocols. The results were compared by statistical analysis (interobserver agreement - Gwet coefficient; analysis of the qualitative variables - Stuart-Maxwell test; and analysis of the quantitative variables - Wilcoxon test). RESULTS: After exclusion of four patients, the final sample consisted of 66 patients. A good/excellent inter observer agreement was stablished for subjective criteria (except in one criteria). For the qualitative analysis the amount of good or excellent evaluations was higher for the monoexponential protocol (except in one category), with evidence of significant differences for three criteria (diffusion weighted imaging global quality; diffusion weighted imaging signal-to-noise ratio; and apparent diffusion coefficient signal-to-noise ratio). For the quantitative data analysis, the monoexponential protocol showed less variability of the anteroposterior diameters, meaning less distortion of the images, and better estimated signal-to-noise ratio. CONCLUSION: In our data, the quality of the images of the monoexponential standard diffusion sequence was qualitatively and quantitatively superior to those of the biexponential diffusion weighted imaging sequence.

Interobserver Agreement and Positivity of PI-RADS Version 2 Among Radiologists with Different Levels of Experience.

RATIONALE AND OBJECTIVES: To evaluate interobserver agreement of Prostate Imaging Reporting and Data System (PI-RADS) v2 category among radiologists with different levels of experience. The secondary objective was to evaluate the positivity for significant cancer among each category (splitting category 4 into two) and among different lesion sizes. MATERIALS AND METHODS: Institutional review board and ethics comitee approved retrospective study. Eight radiologists with different levels of experienced in prostatic magnetic resonance imaging-two more experienced, four with intermediate experience, and two abdominal radiology fellows-interpreted 160 lesions. Reference standard was fusion-targeted biopsy. Percentage agreement, k coefficients, and analysis concordance were used. RESULTS: Coefficient of concordance according to categories was 0.71 considering both zones, 0.72 for peripheral zone (PZ) and 0.44 for peripheral zone (TZ). Agreement for PI-RADS score of 3 or greater was 0.48 in PZ and 0.57 in TZ. Tumor positivity rates were 54.3% and 66.0% for PI-RADS 3 + 1 and 4 for PZ, respectively; and 25.0 and 49.2% for PI-RADS 3 + 1 and 4 for TZ, respectively (p < 0.001 in both analysis). Lesions <10, 10-14, and ≥15 mm had 55.3%, 74.6%, and 93.5% of positivity rates for cancer in PZ (p = 0.002 and <0.001) and 26.7%, 56.5%, and 59.6% in TZ, respectively (p = 0.245 and 0.632). Sensitivities, specificities, and accuracies of magnetic resonance imaging for prostate cancer using PI-RADS v2 were 76%, 72%, and 74% for PZ; and 76%, 69%, and 71% for TZ, respectively. CONCLUSION: This study shows that PI-RADS v2 has overall good interobserver agreement among radiologists with different levels of experience. PI-RADS category 3 + 1 showed lower positivity rates for significant cancer compared to category 4. Lastly, lesions 10-14 mm has similar positivity rates compared to ≥15 mm for TZ lesions.

Comparison of complications rates between multiparametric magnetic resonance imaging-transrectal ultrasound (TRUS) fusion and systematic TRUS prostatic biopsies.

PURPOSE: The aim of this study was to compare the complication rates between transrectal ultrasound (TRUS) systematic prostate biopsy and multiparametric magnetic resonance imaging (MRI)-TRUS fusion prostate biopsy techniques. MATERIALS AND METHODS: This is a single-center retrospective study, institutional review board approved. Systematic TRUS and MRI-TRUS fusion prostate biopsy complication rates were compared in 967 men. A total of 319 patients were received systematic TRUS prostate biopsy and 648 patients underwent systematic TRUS + MRI-TRUS fusion prostate biopsy. Complications were divided into immediate (those that occurred during the hospital observation period) and late (those that occurred within 5 days after biopsy). RESULTS: Seventeen complications were observed in patients who received either a systematic prostate biopsy or MRI-TRUS fusion prostate biopsy. Severe complications were not observed in both groups. Among patients who underwent systematic prostate biopsy, 6 (1.9%) cases of complications were observed and between those who received MRI-TRUS fusion prostate biopsy 11 (1.7%) cases of complications after the procedure (p = 0.873) were observed, with no statistical difference between groups. Also, no statistical differences between early and late complication groups (p > 0.999) were observed. CONCLUSIONS: The complication rates were low in both groups, with no critical clinical outcomes and no significant difference of complication rates between systematic TRUS prostate biopsy and MRI-TRUS fusion prostate biopsy techniques.

Comparative study between monoexponential and biexponential diffusion weighted imaging sequences in multiparametric prostate magnetic resonance imaging / Estudo comparativo entre as sequências de difusão monoexponencial e biexponencial na ressonância magnética multiparamétrica da próstata

ABSTRACT Objective: To compare qualitatively and quantitatively, in terms of image quality, a new biexponential diffusion sequence protocol with the standard monoexponential diffusion protocol on multiparametric prostate magnetic resonance imaging. Methods: This study had a prospective data collection and cross-sectional analysis. Between August and November 2017, a total of 70 patients who underwent multiparametric prostate magnetic resonance imaging due to clinical suspicion of prostatic neoplasia were recruited. The images obtained were evaluated by two independent readers regarding subjective/qualitative criteria (six criteria) and objective/quantitative criteria (three criteria), always comparing the monoexponential to biexponential acquisition protocols. The results were compared by statistical analysis (interobserver agreement − Gwet coefficient; analysis of the qualitative variables − Stuart-Maxwell test; and analysis of the quantitative variables − Wilcoxon test). Results: After exclusion of four patients, the final sample consisted of 66 patients. A good/excellent inter observer agreement was stablished for subjective criteria (except in one criteria). For the qualitative analysis the amount of good or excellent evaluations was higher for the monoexponential protocol (except in one category), with evidence of significant differences for three criteria (diffusion weighted imaging global quality; diffusion weighted imaging signal-to-noise ratio; and apparent diffusion coefficient signal-to-noise ratio). For the quantitative data analysis, the monoexponential protocol showed less variability of the anteroposterior diameters, meaning less distortion of the images, and better estimated signal-to-noise ratio. Conclusion: In our data, the quality of the images of the monoexponential standard diffusion sequence was qualitatively and quantitatively superior to those of the biexponential diffusion weighted imaging sequence.

RESUMO Objetivo: Comparar qualitativa e quantitativamente, em termos de qualidade de imagem, um novo protocolo de sequência de difusão biexponencial com o protocolo de difusão monoexponencial padrão, em ressonância magnética multiparamétrica da próstata. Métodos: Estudo com coleta prospectiva e análise transversal. Entre agosto e novembro de 2017, foram recrutados 70 pacientes que realizaram ressonância magnética multiparamétrica da próstata, por suspeita de neoplasia prostática. As imagens obtidas por ambas as sequências foram avaliadas por dois leitores independentes, quanto a critérios de avaliação subjetiva/qualitativa (seis critérios) e objetiva/quantitativa (três critérios), sempre comparando os protocolos de aquisição monoexponencial e biexponencial. Os resultados foram comparados por análise estatística (concordância interobservador − coeficiente de Gwet; análise das variáveis qualitativas − teste de Stuart-Maxwell; e análise das variáveis quantitativas − testes de Wilcoxon). Resultados: Após exclusão de quatro pacientes, a amostra final foi composta por 66 pacientes. Uma boa/excelente concordância interobservador foi estabelecida para critérios subjetivos (exceto em um critério). Para a análise qualitativa, a quantidade de avaliações boas ou excelentes foi maior para o protocolo monoexponencial (exceto em uma categoria), com evidências de diferenças significativas para três critérios (qualidade global da imagem ponderada em difusão, relação sinal-ruído na imagem ponderada em difusão e relação sinal-ruído ADC). Para a análise quantitativa dos dados, o protocolo monoexponencial apresentou menor variabilidade dos diâmetros anteroposteriores, o que significou menos distorção das imagens, e melhor relação sinal-ruído estimada. Conclusão: Em nossos dados, a qualidade das imagens da sequência de difusão padrão monoexponencial foi qualitativa e quantitativamente superior àquelas da sequência teste biexponencial.

Comparison between multiparametric MRI with and without post - contrast sequences for clinically significant prostate cancer detection

ABSTRACT Background: Dynamic-contrast enhanced (DCE) sequence is used to increase detection of small lesions, based on increased vascularization. However, literature is controversy about the real incremental value of DCE in detection of clinically significant (CS) prostate cancer (PCa), since absence of enhancement does not exclude cancer, and enhancement alone is not definitive for tumor. Purpose: To test the hypothesis that DCE images do not increase CS PCa detection on MRI prior to biopsy, comparing exams without and with contrast sequences. Material and Materials and Methods: All men who come to our institution to perform MRI on a 3T scanner without a prior diagnosis of CS PCa were invited to participate in this study. Reference standard was transrectal prostate US with systematic biopsy and MRI/US fusion biopsy of suspicious areas. Radiologists read the MRI images prospectively and independently (first only sequences without contrast, and subsequently the entire exam) and graded them on 5-points scale of cancer suspicion. Results: 102 patients were included. Overall detection on biopsy showed CS cancer in 43 patients (42.2%), clinically non-significant cancer in 11 (10.8%) and negative results in 48 patients (47%). Positivities for CS PCa ranged from 8.9% to 9.8% for low suspicion and 75.0% to 88.9% for very high suspicion. There was no statistical difference regarding detection of CS PCa (no statistical difference was found when compared accuracies, sensitivities, specificities, PPV and NPV in both types of exams). Inter-reader agreement was 0.59. Conclusion: Exams with and without contrast-enhanced sequences were similar for detection of CS PCa on MRI.