A multidetector tomography protocol for follow-up of endovascular aortic aneurysm repair

OBJECTIVE: The purpose of this study was to improve the use of 64-channel multidetector computed tomography using lower doses of ionizing radiation during follow-up procedures in a series of patients with endovascular aortic aneurysm repair. METHODS: Thirty patients receiving 5 to 29 months of follow-up after endovascular aortic aneurysm repair were analyzed using a 64-channel multidetector computed tomography device by an exam that included pre-and postcontrast with both arterial and venous phases. Leak presence and type were classified based on the exam phase. RESULTS: Endoleaks were identified in 8/30 of cases; the endoleaks in 3/8 of these cases were not visible in the arterial phases of the exams. CONCLUSION: The authors conclude that multidetector computed tomography with pre-contrast and venous phases should be a part of the ongoing follow-up of patients undergoing endovascular aortic aneurysm repair. The arterial phase can be excluded when the aneurism is stable or regresses. These findings permit a lower radiation dose without jeopardizing the correct diagnosis of an endoleak

Comparação entre ultrassonografia, tomografia computadorizada e ressonância nuclear magnética com medidas intra-operatórias na avaliação dos aneurismas de aorta abdominal

PURPOSE: To study the imaging exams more commonly used for abdominal aortic aneurysms evaluation - ultrasonography, conventional computerized tomography, helical computerized tomography and nuclear magnetic angioresonance - comparing the preoperative measurements reached by those radiological methods with the measurements made during the surgical procedures. METHODS: Patients who had indication of elective transperitoneal surgical treatment for their abdominal aortic aneurysms were included in the study. The initial diagnosis of the aortic dilatation was made by ultrasonography and, after the surgical treatment was indicated, the patient was submitted to another imaging method. Sixty patients were divided into 3 groups according to the complementary imaging method (conventional computerised tomography, helical computerized tomography, nuclear magnetic angioresonance). The ultrasonography of the first 20 patients were joined in a fourth group. There were considered in the study the measurements of the transversal diameter of the proximal neck, maximum transversal diameter of the aneurysm, straight-line length and transversal diameter of the common iliac arteries given by the imaging methods. The same measurements were made by using a caliper during the surgical procedure, and then compared to the values obtained from the radiological exams. RESULTS: The maximum transverse diameter had a range measurement variation of 4.5 to 13.6 cm in the intraoperative, with no statistically significant differences when compared with all the imaging tests. The ultrasonography, however, overestimated the measurements of the proximal neck and the common iliac arteries, in comparison with intraoperative measures. The length of the aorta aneurysm obtained by the conventional computerized tomography was significantly lower if compared to the measures done with the calliper during the operation. The helical computerized tomography and the nuclear magnetic angioresonance provided measurements with no significant differences in the statistic view when compared to the intraoperative measures. CONCLUSIONS: Ultrasonography is a reliable method for the diagnosis and follow-up of the aorta abdominal aneurysms, but insufficient for endovascular surgery planning. The conventional computed tomography can provoke distortion in the length measurements of the aorta dilatation. Helical computed tomography and nuclear magnetic angioresonance provided precise measurements of all the studied parameters, being of great utility for surgical planning.OBJETIVO: Estudar os métodos mais freqüentemente empregados na avaliação dos aneurismas de aorta abdominal - ultrassonografia, tomografia computadorizada convencional, tomografia computadorizada helicoidal e angio-ressonância nuclear magnética - comparando as medidas fornecidas por estes exames radiológicos no pré-operatório com medidas realizadas durante a operação. MÉTODO: Foram incluídos no estudo pacientes portadores de aneurisma da aorta abdominal com indicação de tratamento cirúrgico eletivo por via transperitoneal. O diagnóstico inicial da dilatação aórtica foi feito com ultra-sonografia e, uma vez indicado o tratamento cirúrgico, era então solicitado um outro exame radiológico complementar, já que não é nossa rotina operar esses pacientes com base apenas na ultra-sonografia. Sessenta pacientes foram divididos em 3 grupos de acordo com o exame complementar realizado (tomografia computadorizada convencional, tomografia computadorizada helicoidal ou angio-ressonância nuclear magnética). As ultra-sonografias dos 20 primeiros pacientes foram incluídas em um 4° grupo. Analisamos neste estudo as medidas do colo proximal da aorta, o diâmetro transverso máximo e o comprimento do aneurisma, além do diâmetro transverso das artérias ilíacas comuns conseguidos a partir dos exames radiológicos. As mesmas medidas eram realizadas por ocasião da operação com o auxílio de um paquímetro e , então, comparadas aos valores indicados pelos exames de imagem. RESULTADOS: As medidas do diâmetro transverso máximo do aneurisma variaram de 4.5 a 13.6 cm no intra-operatório, não apresentando diferença estatisticamente significativa em relação a nenhum dos exames radiológicos estudados. A ultra-sonografia, entretanto, superestimou as medidas do colo proximal da aorta e dos diâmetros transversos das artérias ilíacas, em comparação com os valores auferidos durante o tratamento cirúrgico. O comprimento dos aneurismas medidos pela tomografia computadorizada convencional era menor em relação às medições feitas com o paquímetro de maneira estatisticamente significativa. Tanto a tomografia computadorizada helicoidal quanto a angio-ressonância nuclear magnética proporcionaram medidas sem diferença significante do ponto de vista estatístico para todos os parâmetros estudados, quando confrontados com os valores obtidos no intra-operatório. CONCLUSÕES: A ultra-sonografia consiste em método valioso para o diagnóstico e seguimento clínico de pacientes com aneurisma de aorta abdominal, sendo, porém, insuficiente para o planejamento de tratamento por técnica endovascular. A tomografia computadorizada convencional pode induzir a erro na estimativa da extensão crânio-caudal do aneurisma. A tomografia computadorizada helicoidal e a angio-ressonância nuclear magnética geraram medidas precisas de todos os parâmetros estudados, sendo ambos de grande importância para a programação operatória

Evaluation of adrenal tumors by magnetic resonance imaging with histological correlation

A ressonância magnética é ferramenta importante para a detecção e caracterização dos tumores adrenais. O conhecimento das diferentes apresentações dos tumores primários e secundários à ressonância magnética e sua correlação com dados da histologia são essenciais para o correto raciocínio diagnóstico. Este artigo revisa os aspectos que podem estreitar o diagnóstico diferencial dos tumores adrenais, dando ênfase à correlação histológica daqueles mais comuns.Magnetic resonance imaging is an important tool for the detection and characterization of adrenal tumors. The knowledge about the different presentations of primary and secondary adrenal tumors at magnetic resonance imaging and their correlation with histological data are essential for the establishment of a correct diagnosis. The present study reviews magnetic resonance imaging aspects which may narrow the differential diagnosis of adrenal tumors, emphasizing the histological correlation of the most frequent ones

Search of prostatic tissue in 46,XX congenital adrenal hyperplasia

OBJETIVOS: Verificar a ocorrência de tecido prostático em pacientes portadoras da forma clássica de hiperplasia congênita das suprarrenais, com cariótipo 46,XX e analisar a sensibilidade e a especificidade do antígeno prostático específico (PSA) das pacientes com hiperplasia congênita das suprarrenais em relação à detecção de tecido prostático na ressonância magnética (RNM) de região pélvica. MÉTODOS: Foram estudadas 52 crianças e adolescentes, sendo 32 meninas portadoras da forma clássica de hiperplasia congênita das suprarrenais, 10 meninas e 10 meninos sem hiperplasia congênita das suprarrenais. A RNM da região pélvica e a coleta de PSA, diidrotestosterona e testosterona foram realizadas em todos os pacientes. Para analisar a capacidade de discriminação do antígeno prostático-específico, foi utilizada a curva ROC (receiver operating characteristic curve). RESULTADOS: Cinco das 32 pacientes portadoras de hiperplasia congênita das suprarrenais apresentaram tecido prostático na RNM de região pélvica. Para concentração de antígeno prostático-específico de 0,1 ng/mL, obteve-se sensibilidade de 100% e especificidade de 88,9% para a detecção de tecido prostático. CONCLUSÕES: A ocorrência de tecido prostático nas pacientes portadoras de hiperplasia congênita das suprarrenais estudadas foi de 15,6%. O antígeno prostático-específico mostrou ser valioso marcador de tecido prostático nestas pacientes.OBJECTIVES: To describe the presence of prostatic tissue in 46,XX patients with the classical form of congenital adrenal hyperplasia (CAH); to evaluate the sensitivity and specificity of prostatic specific antigen (PSA) measured in congenital adrenal hyperplasia patients with regard to the detection of prostatic tissue in pelvic MRI. METHODS: We studied 52 children and adolescents, 32 with the classical form of congenital adrenal hyperplasia, 10 boys and 10 girls without CAH. Pelvic MRI was performed in all patients to detect prostatic tissue. Prostate specific antigen, testosterone and dihydrotestosterone were measured in all patients. We used Receiver Operating Characteristic Curve for PSA discrimination capacity. RESULTS: Five girls with congenital adrenal hyperplasia showed image of prostatic tissue on pelvic MRI. Prostate specific antigen showed sensitivity and specificity of 100% and 88.9%, respectively, taking 0.1 ng/mL as the cutoff level. CONCLUSIONS: The incidence of prostatic tissue in 46,XX patients with the classical form of congenital adrenal hyperplasia was 15.6%. PSA demonstrated to be a good marker of prostatic tissue in these patients and should be used to screen patients to be submitted to image studies

CLINICAL TUMOR DIMENSIONS MAY BE USEFUL TO PREVENT GEOGRAPHIC MISS IN CONVENTIONAL RADIOTHERAPY OF UTERINE CERVIX CANCER-A MAGNETIC RESONANCE IMAGING-BASED STUDY

Purpose: To evaluate the risk of geographic miss associated with the classic four-field ""box"" irradiation technique and to define the variables that predict this risk. Materials and Methods: The study population consisted of 80 patients with uterine cervix cancer seen between 2001 and 2006. Median age was 55 years (23-82 years), and 72 (90%) presented with squamous cell carcinoma. Most patients (68.7%) presented with locally advanced disease (IIb or more). Magnetic resonance imaging findings from before treatment were compared with findings from simulation of the conventional four-field ""box"" technique done with rectal contrast. Study variables included tumor volume; involvement of vagina, parametrium, bladder, or rectum; posterior displacement of the anterior rectal wall; and tumor anteroposterior diameter (APD). Margins were considered adequate when the target volume (primary tumor extension, whole uterine body, and parametrium) was included within the field limits and were at least 1 cm in width. Results: Field limits were inadequate in 45 (56%) patients: 29 (36%) patients at the anterior and 28 (35%) at the posterior border of the lateral fields. Of these, 12 patients had both anterior and posterior miss, and this risk was observed in all stages of the disease (p = 0.076). Posterior displacement of the anterior rectal wall beyond S2-S3 was significantly correlated with the risk of geographic miss (p = 0.043). Larger tumors (APD 6 cm or above and volume above 50 cm(3)) were also significantly correlated with this risk (p = 0.004 and p = 0.046, respectively). Conclusions: Posterior displacement of the anterior rectal wall, tumor APD, and volume can be used as guidance in evaluating the risk of geographic miss. (C) 2009 Elsevier Inc

Findings of Pelvic Endometriosis at Transvaginal US, MR Imaging, and Laparoscopy

Endometriosis is a common multifocal gynecologic disease that manifests during the reproductive years, often causing chronic pelvic pain and infertility. It may occur as invasive peritoneal fibrotic nodules and adhesions or as ovarian cysts with hemorrhagic content. Although findings at physical examination may be suggestive, imaging is necessary for definitive diagnosis, patient counseling, and treatment planning. The imaging techniques that are most useful for preoperative disease mapping are transvaginal ultrasonography (US) after bowel preparation, and magnetic resonance (MR) imaging. Initial transvaginal US is a reliable technique for detecting rectosigmoid endometriotic lesions. MR imaging is indicated as a complementary examination in complex cases of endometriosis with extensive adhesions and ureteral involvement. Peritoneal endometriotic implants are typically hypoechoic on transvaginal US images and demonstrate low signal intensity on T2-weighted MR images. Endometriotic implants most commonly are found in retrocervical and rectosigmoid sites, followed by the vagina, bladder, and ureters. Cysts with low-level internal echoes and echogenic peripheral foci at transvaginal US are suggestive of endometriomas. MR imaging has high specificity for identifying endometriomas, which are characterized by high signal intensity on T1-weighted images and low signal intensity on T2-weighted images. Correlation of the radiologic imaging features of endometriotic lesions with their laparoscopic appearances may help improve individual proficiency in the radiologic diagnosis of endometriosis. Supplemental material available at http:// radiographics.rsna.org/lookup/suppl/doi: 10.1148/rg.314105193/-/DC1. (C) RSNA, 2011 radiographics.rsna.or