Hepatic hemangioma is frequently asymptomatic, and bleeding is rare, even in cases of large lesions. The authors report the case of a 31-year-old female patient presenting with acute abdominal pain, whose imaging studies have demonstrated hematoma in the left hepatic lobe associated with hemoperitoneum. The patient was submitted to left hepatectomy, with a final histopathological diagnosis of cavernous hemangioma.

Keywords: Hepatic hemangioma, Hemoperitoneum, Computed tomography, Acute abdomen

OBJECTIVE: To establish the role of MRI T2-weighted sequences in the differentiation between simple cysts and hepatic hemangiomas. MATERIALS AND METHODS: A double-blinded, prospective, observational, cross-sectional study evaluated 52 patients with 91 hepatic lesions (34 simple cysts and 57 hemangiomas) submitted to abdominal magnetic resonance imaging. The combined analysis of all sequences was considered as the golden-standard. TSE sequences with long echo trains and b-FFE sequences were subjectively analyzed by two independent observers for differentiating cysts from hemangiomas. The kappa test (κ) was utilized in the analysis of the methods accuracy and inter- and intra-observer agreement (p < 0.05*). RESULTS: Cysts and hemangiomas dimensions ranged respectively between 0.5 and 6.5 cm (mean = 1.89 cm), and 0.8 and 11 cm (mean = 2.62 cm). The analysis of the sequences with long-TE and the golden-standard demonstrated a non-statistically significant agreement (κ: 0.00-0.10). The agreement between the evaluation of the b-FFE sequence and the golden-standard ranged from substantial (κ: 0.62-0.71) to almost perfect (κ: 0.86) for both observers. The inter- and intra-observer agreement for the b-FFE sequence ranged from substantial (κ: 0.62-0.70) to almost perfect (κ: 0.85-0.91). CONCLUSION: T2-weighted images acquired with the b-FFE technique present a high accuracy and reproducibility in the differentiation between cysts and hepatic hemangiomas.

Keywords: Liver, Cyst, Hemangioma, Magnetic resonance imaging

OBJECTIVE: To investigate and describe clinical, radiologic and pathologic findings of gastrointestinal stromal tumors. MATERIALS AND METHODS: In the period between December 2000 and March 2006, 16 patients were submitted to surgery for gastrointestinal stromal tumors in our institution. The following variables were taken into consideration: sex and age, signs and symptoms at presentation, tumor site and size, radiological and pathological features, and presence of metastasis. RESULTS: The study population was constituted by nine men and seven women. The primary tumor sites of origin were: stomach (n = 5), rectum (n = 4), small bowel (n = 3), mesentery (n = 3), and colon (n = 1). Mean primary tumor size was 9 cm. Computed tomography was the main radiological method utilized. Circumscribed, lobulated and heterogeneously contrast-enhanced mass was the main image finding. Metastasis was found in nine patients (56% of cases) at presentation or tumor recurrence was observed during the follow-up period (mean = 32 months). CONCLUSION: Gastrointestinal stromal tumor occurs in middle-age adults and the elderly, and must be taken into consideration as differential diagnosis for abdominal masses. Early diagnosis, adequate therapy, and rigorous follow-up are essential, considering the high probability of malignancy of these neoplasms as demonstrated by the present study.

Keywords: Gastrointestinal stromal tumor, Gastrointestinal neoplasms, Gastrointestinal diseases, Sarcoma

Hemangiomas are the most common benign tumors of the liver, occurring in all age groups, and more frequently in adults. The vast majority of hemangiomas are small, asymptomatic, and are incidentally discovered. Larger lesions may eventually produce symptoms. The sonographic aspect of these tumors varies, the lesions being typically small, well defined and hyperechoic. In this study the authors review clinical and sonographic features of hemangiomas, highlighting the clinical significance of such features to be taken into consideration in the treatment of affected patients.

Keywords: Hemangioma, Liver, Ultrasound

OBJECTIVE: The aim of this study is to obtain an alternative angiographic diagnostic method which can be used in patients at a high risk for the use of iodine contrast medium. MATERIALS AND METHODS: Twenty-six patients with chronic renal failure whose fistulas were assessed by digital angiography were first evaluated using iodine contrast medium. Subsequently, carbon dioxide was used as contrast medium, and the images were printed in angiographic film. The angiographic studies were evaluated for opacification, radiological diagnosis and vessel diameter by two independent vascular surgeons; the author performed a comparative analysis of the measurement of the artery and the vein, and respiratory frequency before and after contrast injection. RESULTS: The results obtained with the statistical analysis using kappa coefficient showed agreement between the two doctors and were 0.3217 for opacification, 0.5583 for radiological diagnosis and of 0.4298 for the analysis of vessel diameter. For the carbon dioxide technique, no significant difference was seen in the comparative analysis of the measures of the artery (p = 0.3657) and vein (p = 0.2041), in the position measurements and dispersion; the analysis of the position measurements and dispersion for respiratory frequency showed no significant difference. CONCLUSION: We concluded that this method can be used as an alternative for angiographic study in patients with history of allergy or risk of nephrotoxicity.

Keywords: Angiography using carbon dioxide, Renal failure, Arteriovenous fistula

OBJECTIVE: To evaluate the qualitative (morphological) and quantitative characteristics of hepatic hemangiomas with magnetic resonance imaging. MATERIAL AND METHODS: Twenty-seven patients with 57 hemangiomas were prospectively studied with magnetic resonance imaging using a system operating at 1.5 T. T1- and T2-weighted spin-echo images were obtained, including heavily T2-weighted images with TE of 160 ms. The morphological characteristics of the hemangiomas were studied and the lesions were classified as typical or atypical. Quantitative parameters (T2 relaxation time, simplified T2 index and lesion/liver signal intensity ratio) were also calculated. The values obtained for typical and atypical hemangiomas were compared as well as for the hemangiomas measuring £ 2.0 cm and > 2.0 cm. RESULTS: 78.9% of hemangiomas showed typical morphological features. There was no difference between the quantitative values for typical and atypical hemangiomas. There was not significant difference in T2 relaxation times and values of simplified T2 index in hemangiomas measuring £ 2.0 cm and > 2.0 cm. Lesion/liver signal intensity ratios showed significant differences between the two groups. T2 relaxation times, the simplified T2 index and the lesion/liver signal intensity ratios correctly characterized 96.5%, 93%, and 89.5% of the hemangiomas, respectively. CONCLUSION: Quantitative analysis of hepatic hemangiomas is a simple technique that in conjunction with morphological evaluation provides a more reliable characterization of these tumors.

Keywords: Liver, Hemangioma, Magnetic resonance imaging

Hemangiomas are benign hepatic tumors that in most cases require no surgical excision if correctly identified. Ultrasound (US) usually shows hyperechogenic tumors although some unusual hypoechogenic hemangiomas have also been described. Fifteen patients with hypoechogenic hemangiomas, identified in a period of approximately four years, were evaluated prospectively. As the US findings of these hemangiomas were atypical, the final diagnosis was established after a combined analysis of US and helical computed tomography (helical-CT) findings. Helical-CT showed centripetal enhancement after administration of intravenous iodinated contrast media in all lesions. The levels of carcinoembrionic antigen and alpha-fetoprotein were measured in all patients who were also submitted to endoscopy and colonoscopy (or double contrast enema). No abnormalities were found in any of these tests. Additionally, US and helical-CT examinations were performed 8 to 12 months after the initial investigation in all patients, and no changes were seen in the appearance and dimensions of the lesions. There was associated steatosis in 14 of the 15 patients with hypoechogenic hemangiomas. The authors concluded that atypical hypoechogenic hemangiomas occur mainly in patients with steatosis and only occasionally in patients with nonsteatotic liver. In these atypical cases complementary imaging and biochemical studies, and follow-up tests are necessary to establish an accurate diagnosis.

Keywords: Liver, Hemangioma, Hypoechogenic hemangioma, Ultrasonography

We report the clinical and imaging findings of a patient with a symptomatic vertebral hemangioma treated with radiotherapy alone. There was partial relief of the pain 3 months after radiotherapy. We recommend a total dose of 40 Gy at 2 Gy per fraction. A review of literature is also presented.

Keywords: Hemangioma, Radiotherapy, Spine

OBJECTIVE: To report results of the application of endovascular techniques in the management of scalp cirsoid aneurysms. MATERIALS AND METHODS: Four patients diagnosed with cirsoid aneurysms were submitted to treatment by endovascular approach. All the four patients included in the present series had arteriovenous malformations and were treated solely by embolization. RESULTS: Three of the patients underwent endovascular treatment by transarterial embolization and one was treated by direct puncture of the venous segment. Both clinical and cosmetic outcomes were satisfactory in all of the patients. Clinical relapse was not observed along the follow-up period. CONCLUSION: The endovascular approach is safe and effective in the management of crisoid aneurysms. Although this technique can be used as an adjuvant or complement to surgery, particularly in cases where deep afferents are involved, complete resolution can be achieved only with endovascular treatment. The choice of treatment method should be based on a range of typical characteristics of the lesion, including angioarchitecture, size and clinical presentation.

Keywords: Arteriovenous fistula; Cirsoid aneurysm; Cerebral angiography; Embolization.

Breast hemangioma is a rare benign tumor that presents either absent or low 18F-fluoro-2-deoxy-D-glucose (FDG) uptake at positron emission tomography (PET). The authors report the case of a breast nodule pathologically compatible with hemangioma in a woman whose PET-scan has demonstrated increased FDG uptake (simulating a malignant tumor). A brief review of factors leading to false positive and false negative PET results is also undertaken.

Keywords: PET/CT; FDG-18F; Hemangioma; Breast.

Gastrointestinal bleeding is a common cause of admission to emergency services. Hemorrhages originated from arteriovenous malformations in the stomach have been rarely described in the literature. Embolization offers a good chance for the control of bleeding. We describe the case of a patient with recurrent hematemesis and melena whose angiography identified arteriovenous malformations in the greater curvature of the stomach. The bleeding was treated by arterial embolization.

Keywords: Arteriovenous malformation; Gastrointestinal hemorrhage; Embolization.

Rendu-Osler-Weber syndrome or hereditary hemorrhagic telangiectasia is an autosomal dominant vascular disease involving multiple systems whose main pathological change is the presence of abnormal arteriovenous communications. Most common symptoms include skin and mucosal telangiectasias, epistaxis, gastrointestinal, pulmonary and intracerebral bleeding. The key imaging finding is the presence of visceral arteriovenous malformations. The diagnosis is based on clinical criteria and can be confirmed by molecular biology techniques. Treatment includes measures for management of epistaxis, as well as surgical excision, radiotherapy and embolization of arteriovenous malformations, with emphasis on endovascular treatment. The present pictorial essay includes a report of three typical cases of this entity and a literature review.

Keywords: Rendu-Osler-Weber; Hereditary hemorrhagic telangiectasia; Arteriovenous fistula; Epistaxis.

Arteriovenous fistulae of the cavernous sinus are rare and difficult to diagnose. They are classified into dural cavernous sinus fistulae or direct carotid-cavernous fistulae. Despite the similarity of symptoms between both types, a precise diagnosis is essential since the treatment is specific for each type of fistula. Imaging findings are remarkably similar in both dural cavernous sinus fistulae and carotid-cavernous fistulae, but it is possible to differentiate one type from the other. Amongst the available imaging methods (Doppler ultrasonography, computed tomography, magnetic resonance imaging and digital subtraction angiography), angiography is considered the gold standard for the diagnosis and classification of cavernous sinus arteriovenous fistulae. The present essay is aimed at didactically presenting the classification and imaging findings of cavernous sinus arteriovenous fistulae.

Keywords: Arteriovenous fistula; Cavernous sinus; Ultrasonography; Computed tomography; Magnetic resonance imaging; Angiography.

Abdominal vascular syndromes are rare diseases. Although such syndromes vary widely in terms of symptoms and etiologies, certain imaging findings are characteristic. Depending on their etiology, they can be categorized as congenital—including blue rubber bleb nevus syndrome, Klippel-Trenaunay syndrome, and hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber syndrome)—or compressive—including "nutcracker" syndrome, median arcuate ligament syndrome, Cockett syndrome (also known as May-Thurner syndrome), and superior mesenteric artery syndrome. In this article, we aimed to illustrate imaging findings that are characteristic of these syndromes, through studies conducted at our institution, as well as to perform a brief review of the literature on this topic.

Keywords: Gastrointestinal tract; Venous thrombosis; Arteriovenous fistula; Hemangioma.

OBJECTIVE: To identify the main hemorrhagic complications after percutaneous nephrolithotomy, as well as the results obtained with transcatheter arterial embolization (TAE) at an interventional radiology center. MATERIALS AND METHODS: This was a retrospective analysis of patients undergoing TAE for the treatment of hemorrhagic complications after percutaneous nephrolithotomy. All patients underwent computed tomography angiography (CTA). RESULTS: We evaluated a total of nine patients. At emergency department readmission, the most common symptom was macroscopic hematuria, which was seen in five patients. Three patients had an isolated pseudoaneurysm, two had a pseudoaneurysm together with active bleeding (perirenal hematoma), and one had a pseudoaneurysm together with arteriocalyceal fistula. Arteriovenous fistula was diagnosed in three patients and was not seen in combination with other vascular lesions. We did not identify arteriocalyceal fistula in isolation. Five patients underwent TAE with 6 × 15 mm and 6 × 20 mm microcoils. Four patients underwent TAE with n-butyl-2-cyanoacrylate and ethiodized oil. Follow-up CTAs revealed no complications. CONCLUSION: Because of its high diagnostic accuracy, CTA provides the interventional radiologist with valuable data for individualized therapeutic planning. The TAE procedure is safe and effective. It can therefore be used as a first-line treatment for hemorrhagic complications resulting from percutaneous renal procedures.

Keywords: Nephrolithotomy, percutaneous; Aneurysm, false; Arteriovenous fistula; Embolization, therapeutic/methods; Radiology, interventional; Computed tomography angiography.