Adriano Tachibana

Can contrast-enhanced ultrasound with second-generation contrast agents replace computed tomography angiography for distinguishing between occlusion and pseudo-occlusion of the internal carotid artery?

OBJECTIVE: The purpose of this study was to evaluate the effectiveness of contrast-enhanced ultrasound with a second-generation contrast agent in distinguishing between occlusion and pseudo-occlusion of the cervical internal carotid artery, comparing it with that of conventional Doppler ultrasound and the gold standard, computed tomography angiography. METHOD: Between June 2006 and June 2012, we screened 72 symptomatic vascular surgery outpatients at a public hospital. Among those patients, 78 cervical internal carotid arteries were previously classified as occluded by Doppler ultrasound (without contrast). The patients were examined again with Doppler ultrasound, as well as with contrast-enhanced ultrasound and computed tomography angiography. The diagnosis was based on the presence or absence of flow. RESULTS: Among the 78 cervical internal carotid arteries identified as occluded by Doppler ultrasound, occlusion was confirmed by computed tomography angiography in only 57 (73.1%), compared with 59 (77.5%) for which occlusion was confirmed by contrast-enhanced ultrasound (p>0.5 vs. computed tomography angiography). Comparing contrast-enhanced ultrasound with Doppler ultrasound, we found that the proportion of cervical internal carotid arteries classified as occluded was 24.4% higher when the latter was used (p<0.001). CONCLUSIONS: We conclude that, in making the differential diagnosis between occlusion and pseudo-occlusion of the cervical internal carotid artery, contrast-enhanced ultrasound with a second-generation contrast agent is significantly more effective than conventional Doppler ultrasound and is equally as effective as the gold standard (computed tomography angiography). Our findings suggest that contrast-enhanced ultrasound could replace computed tomography angiography in this regard.

Superficial inferior epigastric artery (SIEA) free flap using perforator vessels as a recipient site: clinical implications in autologous breast reconstruction

BACKGROUND Breast reconstruction with autogenous tissue is a well-established technique, but there are some limitations related to donor-site morbidity. Among available techniques, the superficial inferior epigastric artery (SIEA) flap is the least invasive procedure because it does not require harvesting or incision of the rectus muscle or the abdominal fascia. Besides adequate flap choice, the proper selection of the recipient vessels is an important factor. Thus, the internal mammary perforator branches (IMPBs) have been an attractive option regarding recipient pedicle morbidity. METHODS The investigators reported the use of the free SIEA flap with the IMPBs as a recipient site to reconstruct radical mastectomy. RESULTS Five patients with invasive ductal carcinoma underwent modified radical mastectomy and reconstruction. The IMPBs were selected as the recipient site and a free SIEA flap was used. The donor defect was closed directly without synthetic mesh. Satisfactory breast shape was achieved, and no complications were observed. CONCLUSIONS For selected patients, the SIEA flap and IMPBs may constitute a new alternative for immediate breast reconstruction, because of the possibility of large tissue transfer with minimal donor and recipient area morbidity. The SIEA pedicle size and the quality of IMPB vessels should be carefully evaluated.

Acute and chronic mesenteric ischemia: MDCT findings

A isquemia mesenterica e causada pela reducao do fluxo sanguineo mesenterico. Essa patologia pode ser dividida em aguda e cronica, baseada na rapidez e no grau em que o fluxo sanguineo esta sendo comprometido. Os autores retrospectivamente revisaram 22 casos de isquemia mesenterica, diagnosticados por tomografia computadorizada com mutidetectores (TCMD) em nosso servico, e confirmados por cirurgia ou seguimento clinico. Os achados diagnosticos de isquemia aguda e cronica e sua frequencia foram avaliados. Os avancos na TCMD 3D (tridimensional) permitiram o acesso detalhado aos vasos mesentericos. Alem disso, e possivel demonstrar alteracoes nos segmentos intestinais, auxiliando na identificacao da causa primaria da doenca e podendo identificar as complicacoes associadas a isquemia mesenterica e cronica.

Volumetry and biomechanical parameters detected by 3D and 2D ultrasound in patients with and without an abdominal aortic aneurysm.

The objective was to demonstrate the ability of ultrasound (US) with 3D properties to evaluate volumetry and biomechanical parameters of the aorta in patients with and without abdominal aortic aneurysm (AAA). Thirty-one patients with normal aortas (group 1), 46 patients with AAA measuring 3.0–5.5 cm (group 2) and 31 patients with AAA ⩾ 5.5 cm (group 3) underwent a 2D/3D-US examination of the infra-renal aorta, and the images were post-processed prior to being analyzed. In the maximum diameter, the global circumferential strain and the global maximum rotation assessed by 2D speckle-tracking algorithms were compared among the three groups. The volumetry data obtained using 3D-US from 40 AAA patients were compared with the volumetry data obtained by a contemporary computed tomography (CT) scan. The median global circumferential strain was 2.0% (interquartile range (IR): 1.0–3.0), 1.0% (IR: 1.0–2.0) and 1.0% (IR: 1.0–1.75) in groups 1, 2 and 3, respectively (p < 0.001). The median global maximum rotation decreased progressively from group 1 to group 3 (1.38º (IR: 0.77–2.13), 0.80º (IR: 0.57–1.0) and 0.50º (IR: 0.31–0.75), p < 0.001). AAA volume estimations by 3D-US correlated well with CT (R2 = 0.76). In conclusion, US with 3D properties is non-invasive and has the potential to evaluate volumetry and biomechanical characteristics of AAA.

Rediscussing Anticoagulation in Distal Deep Venous Thrombosis

Background: Distal deep venous thrombosis (DVT) accounts for approximately half of all the cases of lower limb thrombosis. The impact and management of this condition is still controversial. This study aims to evaluate the incidence of pulmonary embolism (PE) in patients with distal DVT in comparison to proximal DVT and evaluate the correlation between DVT and PE extension. Methods: 100 patients with acute lower limb DVT diagnosed with whole leg Doppler ultrasound from January 2006 to December 2014 were retrospectively analyzed. Active investigation for PE was carried out in all patients using multislice computed tomography angiography. Classification of DVT and PE was based on the proximal extension of the thrombus. Results: The overall incidence of PE in our sample patients was 72%. In the subgroup analysis, incidence of PE was equal in both the proximal and distal DVT groups (77%, p > 0.99). PE was detected in 43% of the patients with isolated calf vein thrombosis (ICVT). No statistical difference was observed between the distribution of lobar, segmental and subsegmental PE in the 3 DVT subgroups (p = 0.665); however, truncular PE was only observed in the proximal DVT group. Conclusion: Distal DVT is associated with a high incidence of PE compared to proximal DVT. Distal DVT and ICVT can provoke PE with involvement of proximal vessels in the pulmonary arterial tree, even in asymptomatic patients. Our study arises discussion in the controversial debate regarding the need for routine anticoagulation in distal DVT.

Doença cística adventicial da artéria poplítea: causa infrequente de claudicação intermitente

Intermittent claudication is frequently associated with atherosclerotic disease, but differential diagnosis must be sought in patients with no traditional risk factors. Cystic adventitial disease, of unknown etiology, most frequently affects the popliteal artery, and occasionally presents as intermittent claudication. We report a case of this disease and the surgical treatment, and discuss some aspects related to etiopathogenesis, diagnosis and treatment of this condition.

Comparison of Radiation Dose and Image Quality of Abdominopelvic CT Using Iterative (AIDR 3D) and Conventional Reconstructions

OBJECTIVE The purpose of this study is to compare radiation dose and image quality of abdominopelvic CT studies reconstructed with iterative and conventional techniques. MATERIALS AND METHODS This retrospective study enrolled 99 patients who underwent abdominopelvic CT examinations with the portal venous phase images reconstructed with both filtered back projection and Adaptive Iterative Dose Reduction 3D (AIDR 3D) at different time points. Subjective assessment of image quality was performed by two radiologists who scored axial images for overall quality, sharpness, noise, and acceptability in a blinded fashion. The SD of the mean attenuation of the liver, aorta, and paraspinal muscle (as a measurement of image noise) and contrast-to-noise and signal-to-noise ratios for liver and aorta were used as objective parameters of image quality. Radiation dose parameters included CT dose index volume (CTDIvol), dose-length product, effective dose (ED), and size-specific dose estimate (SSDE). Results were compared for different body mass index (BMI; weight in kilograms divided by the square of height in meters) categories. Paired t test and McNemar paired tests for noninferiority were used, with p < 0.05 considered statistically significant. RESULTS We obtained a 62.5% mean reduction in CTDIvol, a 58% mean reduction in ED, and a 63% mean reduction in SSDE when AIDR 3D was used (p < 0.001). Subjective parameters of image quality were considered noninferior for AIDR 3D studies compared with filtered back projection (p < 0.001), except for the sharpness of images of patients with BMI 20-24.9. Variable results were found regarding objective assessment of image quality. CONCLUSION AIDR 3D allowed a significant reduction in radiation dose of abdominopelvic CT examinations without a loss of image quality in general.

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.

The interface sign

Ascites and pleural effusions represent abnormal accumulations of fluid in the peritoneal and intrathoracic cavity, respectively and are common findings on chest and abdominal computed tomography (CT). These conditions sometimes share the same etiologies, sometimes even coexisting in the same patient. When they occur separately, their differentiation by CT images is not always straightforward, as free fluid tends to accumulate in posterior and lateral pleural recesses and around the liver and spleen in patients lying supine [1]. However, there are some classic CT findings that aid in correct characterization [1, 2]. One classic sign described for this differentiation is the interface sign: in ascites, there is a direct contact of the free peritoneal fluid with the liver and/or spleen, leading to a sharp interface between the fluid and these organs. In pleural effusion, however, both liver and spleen are separated from the fluid in the thorax by the diaphragmatic crus, generating an ill-defined interface. It is noteworthy, however, that although helpful, the interface sign should not be considered isolated, as it may sometimes be misleading [1, 2]. This sign was able to correctly classify 80% of these two fluid collections in its original series [2] (Figs. 1 and 2).