Fernando Ide Yamauchi

Multidetector CT Evaluation of the Postoperative Pancreas

Several pancreatic diseases may require surgical treatment, with most of these procedures classified as resection or drainage. Resection procedures, which are usually performed to remove pancreatic tumors, include pancreatoduodenectomy, central pancreatectomy, distal pancreatectomy, and total pancreatectomy. Drainage procedures are usually performed to treat chronic pancreatitis after the failure of medical therapy and include the Puestow and Frey procedures. The type of surgery depends not only on the patients symptoms and the location of the disease, but also on the expertise of the surgeon. Radiologists should become familiar with these surgical procedures to better understand postoperative changes in anatomic findings. Multidetector computed tomography is the modality of choice for identifying normal findings after surgery, postoperative complications, and tumor recurrence in patients who have undergone pancreatic surgery.

Impact of Renal Anatomy on Shock Wave Lithotripsy Outcomes for Lower Pole Kidney Stones: Results of a Prospective Multifactorial Analysis Controlled by Computerized Tomography

PURPOSE We evaluated which variables impact fragmentation and clearance of lower pole calculi after shock wave lithotripsy. MATERIALS AND METHODS We prospectively evaluated patients undergoing shock wave lithotripsy for a solitary 5 to 20 mm lower pole kidney stone between June 2012 and August 2014. Patient body mass index and abdominal waist circumference were recorded. One radiologist blinded to shock wave lithotripsy outcomes measured stone size, area and density, stone-to-skin distance, infundibular length, width and height, and infundibulopelvic angle based on baseline noncontrast computerized tomography. Fragmentation, success (defined as residual fragments less than 4 mm in asymptomatic patients) and the stone-free rate were evaluated by noncontrast computerized tomography 12 weeks postoperatively. Univariate and multivariate analysis was performed. RESULTS A total of 100 patients were enrolled in the study. Mean stone size was 9.1 mm. Overall fragmentation, success and stone-free rates were 76%, 54% and 37%, respectively. On logistic regression body mass index (OR 1.27, 95% CI 1.11-1.49, p = 0.004) and stone density (OR 1.0026, 95% CI 1.0008-1.0046, p = 0.005) significantly impacted fragmentation. Stone size (OR 1.24, 95% CI 1.07-1.48, p = 0.039) and stone density (OR 1.0021, 95% CI 1.0007-1.0037, p = 0.012) impacted the success rate while stone size (OR 1.24, 95% CI 1.04-1.50, p = 0.029), stone density (OR 1.0015, 95% CI 1.0001-1.0032, p = 0.046) and infundibular length (OR 1.1035, 95% CI 1.015-1.217, p = 0.015) impacted the stone-free rate. The best outcomes were found in patients with a body mass index of 30 kg/m(2) or less, stones 10 mm or less and 900 HU or less, and an infundibular length of 25 mm or less. The coexistence of significant unfavorable variables led to a stone-free rate of less than 20%. CONCLUSIONS Obese patients with higher than 10 mm density stones (greater than 900 HU) in the lower pole of the kidney with an infundibular length of greater than 25 mm should be discouraged from undergoing shock wave lithotripsy.

Malignancy Rate, Histologic Grade, and Progression of Bosniak Category III and IV Complex Renal Cystic Lesions

OBJECTIVE The primary purpose of this study is to determine the malignancy rate, histologic grade, and initial stage of surgically treated complex renal cysts classified as Bosniak category III or IV. For nonsurgical lesions, a secondary objective was to evaluate lesion progression on follow-up examinations. MATERIALS AND METHODS We searched our database for cystic lesions classified as Bosniak III or IV category on CT or MRI from January 2008 to April 2016. Surgically resected lesions, per category, were correlated with information on pathologic reports to obtain malignancy rates. For malignant lesions, histologic grade and initial stage were evaluated. Imaging follow-up of at least 2 years was used to evaluate progression of clinically followed lesions. RESULTS We included 86 lesions in 85 patients in the final analysis. Of the 60 surgically resected lesions (70%), 46 (77%) were malignant and 14 (23%) were benign. Malignancy rates were 72% for Bosniak category III lesions and 86% for Bosniak category IV lesions. Most malignant cysts were early-stage (pT1) cysts with low histologic grades (89% of Bosniak III lesions and 91% of Bosniak IV lesions). Follow-up studies of the surgically resected lesions did not show local recurrence, metastasis, or lymph node enlargement. Among patients with lesions managed by watchful waiting (n = 26), all lesions remained unchanged in terms of size and complexity after at least 2-years of follow-up. CONCLUSION Although high malignancy rates were observed for both Bosniak category III and IV lesions, our results suggest that such malignant cysts are usually early-stage tumors with a low histologic grade. Lesions that underwent follow-up remained unchanged on control examinations. These findings may indicate low aggressiveness of these lesions, supporting the idea that more conservative approaches may be used.

Lead pipe sign in ulcerative colitis

A particular imaging feature that helps in the differentiation between UC and CD is the pattern of bowel wall involvement: the first tends to be limited to the superficial layers in a continuous fashion, while the latter tends to present transmural involvement, interweaving healthy mucosa and inflamed areas [1]. Hypertrophy of muscularis mucosae secondary to continuous regeneration promotes loss of haustration and reduction of the usual colon caliber. Fat proliferation due to chronic inflammation also can contribute to this pattern of continuous colonic involvement [2]. Classically described on barium enema exams (Fig. 1) almost a century ago [3], this appearance of smooth, ahaustral contour was compared to a water or gas pipe (Figs. 1, 2), and later also applied to computed tomography enterography and Magnetic Resonance enterography (Figs. 3, 4). Despite its correlation with UC, the ‘‘Lead Pipe’’ can also be found in other forms of inflammatory bowel diseases, and even in CD. It occasionally accompanies infectious colitides such as tuberculosis and amebiasis, and can be a sign of cathartic colon. The lead pipe sign, while not is not disease-specific, provides an indicator of chronic colonic pathology [1–4].

Obesidade, adiposopatia e biomarcadores de imagem quantitativa

Radiol Bras. 2017 Mai/Jun;50(3):VII–VIII Obesity is a metabolic disease with increasing incidence at a global level. The prevalence of obesity doubled between 1980 and 2014, now corresponding to more than half a billion obese people worldwide. The World Health Organization estimates that more than a third of adults over 18 years of age are now overweight. Obesity plays an important role in the development of several diseases, such as atherosclerosis, diabetes, musculoskeletal conditions (e.g., osteoarthritis, tendinopathy, and carpal tunnel syndrome), and chronic pain. Another important association is the increased risk of cancer. The development of these conditions is likely related to increased production of pro-inflammatory adipokines (e.g., interleukin 6 and tumor necrosis factor alpha) and decreased production of (or decreased tissue sensitivity to) anti-inflammatory adipokines (e.g., adiponectin). The final result is that those individuals are in an inflammatory state and show increased levels of acute phase reagents such as C-reactive protein. In the field of radiology, there is a trend toward more quantitative science that could increase the value of quantitative imaging biomarkers and reduce variability across devices, patients, and time. A quantitative imaging biomarker can be defined as “an objective characteristic derived from an in vivo image measured on a ratio or interval scale as indicators of normal biological processes, pathogenic processes, or a response to a therapeutic intervention”. It is extremely important that measurements can be reproduced by different observers on different equipment. In this context, the Radiological Society of North America has organized a Quantitative Imaging Biomarker Alliance. There is great interest in quantitative measurements of adipose tissue, to serve as imaging biomarkers. Total body adipose tissue can be better understood and quantified through sectional imaging methods such as computed tomography and magnetic

Veia cava marsupial simulando linfonodomegalia na tomografia

Homem de 56 anos, hipertenso e diabetico, assintomatico, submetido a tomografia computadorizada (TC) do abdome com contraste endovenoso para acompanhamento de esteatose hepatica. A TC demonstrou nodulo solido hipervascularizado na cabeca pancreatica (caracteristicas de lesao neuroendocrina – ) e formacao ovalada anterior a bifurcacao aortoiliaca (). Nesta situacao, o corte axial da TC pode simular uma linfonodomegalia, especialmente no contexto clinico oncologico. Entretanto, a avaliacao das diversas fases do exame e das reformatacoes coronais e sagitais auxiliam no correto diagnostico [...]

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 ≥15mm 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 10-14mm has similar positivity rates compared to ≥15mm for TZ lesions.

Correction to: ‘‘Bunch of grapes’’ in complete hydatidiform mole

The original version of this article contained a mistake in the co-author’s first name. The co-author name should read as “Mariana Athaniel Silva Rodrigues” instead of “Marina Athaniel Silva Rodrigues”. It is now corrected with this erratum.

DIAGNOSTIC VALUE OF C-REACTIVE PROTEIN AND THE INFLUENCE OF VISCERAL FAT IN PATIENTS WITH OBESITY AND ACUTE APPENDICITIS

ABSTRACT Background: The C reactive protein (CRP) is one of the most accurate inflammatory markers in acute appendicitis (AA). Obesity leads to a pro-inflammatory state with increased CRP, which may interfere with the interpretation of this laboratory test in AA. Aim: To assess sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of CRP in patients with AA and their correlation to body mass index (BMI) and body fat composition. Method: This is a retrospective study based on clinical records and imaging studies of 191 subjects with histopathologically confirmed AA compared to 249 controls who underwent abdominal computed tomography (CT). Clinical and epidemiological data, BMI, and CRP values were extracted from medical records. CT scans were assessed for AA findings and body composition measurements. Results: CRP values increased according to patients’ BMI, with varying sensitivity from 79.78% in subjects with normal or lean BMI, 87.87% in overweight, and 93.5% in individuals with obesity. A similar pattern was observed for NPV: an increase with increasing BMI, 69.3% in individuals with normal or lean BMI, 84.3% in overweight, and 91.3% in individuals with obesity. There was a positive correlation between CRP and visceral fat area in patients with AA. Conclusions: Variations exist for sensitivity, specificity, PPV, and NPV values of CRP in patients with AA, stratified by BMI. An increase in visceral fat area is associated with elevated CRP across the BMI spectrum.

Complete Calcified Ureteral Stent: A Combined 1-Session Approach

OBJECTIVE To demonstrate a successful 1-session approach to a complete calcified ureteral stent, preserving the affected kidney without complications. PATIENT AND METHODS A 33-year-old man presented at our service with an increased urinary frequency, afebrile urinary tract infection, and left lumbar pain. He underwent a ureterolithotripsy with ureteral stenting 3 years ago. After that intervention, he was lost to follow-up. A noncontrast computed tomography scan revealed a complete calcified ureteral stent (FECal V). After careful preoperative planning, the patient was submitted to a combined 1-step approach including left semirigid ureteroscopy, left percutaneous nephrolithotomy, and an open cystolithotomy in supine decubitus. This video demonstrates the surgical steps of the procedure for a FECal V (completely calcified) stent removal. RESULTS Operative time was 240 minutes. The calcified stent was completely removed. A 6 Fr ureteral catheter and a 16 Fr nephrostomy tube were left at the end of the procedure. No double-J stent was used to avoid the same kind of complication. The patient had no peri- or postoperative complications. A computed tomography scan was performed in the first postoperative day (POD) and revealed 2 small residual fragments (7 mm and 6 mm). The ureteral catheter was removed on the first POD, and the nephrostomy tube on the second POD. The patient was discharged from hospital on the third POD. The patient is now scheduled to a flexible ureteroscopy to treat the small residual fragments. CONCLUSION Forgotten ureteral stent is a surgical challenge, requiring multiple approaches and advanced urologic techniques. Our video illustrates that a less invasive and combined 1-step procedure to preserve the kidney is both safe and feasible, when performed by an experienced surgeon.