Distinction of hemangiomas from hepatic tumors with delayed enhancement by incremental dynamic CT

To analyze the patterns of contrast enhancement and to evaluate clinical utility, we performed table incremental dynamic CT in 21 patients with 30 hepatic hemangiomas and in 12 patients with 26 malignant neoplasms, which showed delayed enhancement. On incremental CT, dense, spotty peripheral enhancement was present in 23 of the 30 (77%) hemangiomas. In contrast, a circumferential bead- or band-like peripheral enhancement was seen in 19 of 26 (73%) malignant neoplasms. The findings were characteristic. We conclude that incremental CT is useful in the differential diagnosis of hepatic hemangioma in routine examination.

CT demonstration of fat density in renal cell carcinoma

The presence of fat in a renal mass is almost pathognomonic of angiomyolipoma. We report a rare instance of CT demonstration of foci of fat density in a renal cell carcinoma.

Embolization in high-flow arteriovenous malformations of the face

Five patients with arteriovenous malformations of the face (4 males and 1 woman; age range, 11-38 years) were treated by selective embolization through the feeding arteries with polyvinyl alcohol particles. Immediate gross angiographical obliteration was obtained in 4 patients, with pronounced reduction of the arteriovenous shunt in the fifth. Clinical symptoms including bleeding, swelling, pulsations, bruit, and disfigurement improved in all the patients followed up for a period of 6 to 21 months. Polyvinyl alcohol particle embolization, without surgical resection, though palliative could be useful in select patients. The classification and diagnosis of congenital vascular malformations is briefly reviewed and treatment discussed.

[Hemangioma of the left ventricle]

The authors describe the case of a histologically proven hemangioma in the left coronary artery of the left ventricle of a 24-year-old woman. The results of the different medical imaging methods applied are described and the treatment of cardiac angiomas is discussed.

Hemangioma of the masseter muscle

Intramuscular hemangiomas are rare benign tumors of vascular origin. The masseter is the muscle most commonly involved in the head and neck. A case of intramuscular masseter hemangioma is presented, the literature reviewed, and appropriate diagnostic modalities discussed.

[Color-coded duplex sonography of liver tumors. Does the blood supply permit a conclusion on staging?]

Real-time ultrasonography is a sensitive screening method in patients with suspected liver tumors. However, sonomorphology does not differentiate between benign and malignant tumors. In a prospective study we examined patients with liver tumors with color-coded duplex ultrasonography to find out whether the perfusion status of the liver tumor permits a differential diagnosis. A total of 108 patients with liver tumors were included, and the results of color-coded duplex sonography were compared with histology, MRI and CT. No correlation was seen between the final diagnosis and the perfusion pattern. The vascular status visualized by color-coded duplex ultrasonography does not permit differentiation between benign and malignant liver tumors.

CT evaluation of orbital osseous hemangioma

Two patients with osseous hemangioma of the orbit, and with typical features on plain radiography and computed tomography, are reported. The typical features of osseous hemangioma of the orbit on computerised tomography (CT) are: expansile bony lesion limited by a thin sclerotic rim, bony trabeculae radiating from the centre to the periphery of the lesion, and absence of an associated extra-tumoral soft tissue mass. To the best of our knowledge this is the first report of osseous hemangioma of the orbit evaluated by CT.

Treatment of infantile subglottic hemangioma with electrocautery

Laryngeal subglottic hemangioma is a rare but potentially life-threatening congenital lesion that can compromise that infant airway. A multitude of medical and surgical modalities have been used in the treatment of this lesion but no single approach has received universal acceptance. Three infants with subglottic hemangiomas were treated successfully with electrocautery; each was managed without tracheostomy. Bronchoscopic electrocautery appears to be a safe, effective, inexpensive way to manage infantile subglottic hemangioma.

Imaging patterns of vascular lesions of the head and neck demonstrated by Tc-99m labeled red blood cells

The authors report on three patients with head and neck masses who demonstrated different imaging patterns on Tc-99m RBC scintigraphy, suggesting different vascular pathology of the lesions. Defining these patterns can be helpful in the diagnosis and decision making concerning the appropriate treatment of these patients.

Spectrum of scintigraphic appearance of liver hemangiomas

Two hundred and twenty five liver hemangiomas in 166 patients were studied with Tc-99m labeled RBC and are the basis for this atlas. All hemangiomas showed various presentations of the perfusion blood pool mismatch, which is the basis for diagnosis. The size of the hemangiomas was the factor that determined the mixing of the Tc-99m RBC with the blood and, hence, the sequence of visualization of the lesion. Hemangiomas may appear as multiple lesions on liver scan and imitate metastases. Ninety-five hemangiomas appeared in 36 patients as multiple focal abnormalities. Hemangiomas are extremely variable in size. They may be huge (31 hemangiomas) and sometimes occupy most of the abdomen. Or they can be very small and are then detected only by SPECT (two cases). Thrombosed large hemangiomas appear as focal defects on Tc-99m RBC.

Differentiation between hepatoma and hemangioma with inversion-recovery snapshot FLASH MRI and Gd-DTPA

Thirty-eight patients with focal liver tumors (20 hepatomas, 18 hemangiomas) were studied by dynamic sequential inversion recovery (IR) snapshot fast low angle shot (FLASH) MR imaging with Gd-DTPA. Immediately after 0.05 mmol/kg Gd-DTPA was administered intravenously for 2-3 s followed by flushing with normal saline for 4-5 s, 10 images were obtained in the first 20 s (time zero is the end of flush, early phase). Then, one image every 30 s from 1 to 3 min (late phase) and images at 5 min and 7 min (delayed phase) were obtained serially. Hepatomas showed total enhancement in 18 of 20 patients in the early phase, and isointense or low intensity enhancement with respect to the surrounding liver parenchyma in 18 patients in the late to delayed phases. Hemangiomas showed peripheral enhancement in 14 patients in the early phase, but did not show total enhancement (except for two hemangiomas less than 3 cm in size) in the early phase, and showed high intensity enhancement in 15 patients in the late phase. Ninety percent of hepatomas and 82% of hemangiomas showed their characteristic enhancement patterns in the early to delayed phases. We conclude that dynamic sequential IR snapshot FLASH MR images enhanced with Gd-DTPA can facilitate differentiation between hepatomas and hemangiomas.

Angiomyolipoma of the kidney: a clinical enigma in diagnosis and management

Renal angiomyolipomas are uncommon benign tumours which clinically mimic renal cell carcinoma. They have characteristic features on ultrasound and CT scanning which may enable their diagnosis preoperatively. We review our experience of six cases of renal angiomyolipoma. These cases highlight the difficulties in making a preoperative diagnosis despite the use of modern scanning. We advocate conservative resection when the diagnosis is made preoperatively and when technically possible, but radical nephrectomy should be performed if there is a possibility of a carcinoma.

Duplex pulsed Doppler sonography in the differential diagnosis of hepatocellular carcinoma and other common hepatic tumours

180 previously untreated consecutive patients with liver tumours (308 lesions), including 104 hepatocellular carcinomas (148 lesions), 43 metastases (116 lesions) and 33 haemangiomas (44 lesions), were studied to determine the value of duplex sonography in the differentiation of hepatocellular carcinoma from other tumours. For lesions measuring less than or equal to 5 cm in diameter, hepatocellular carcinoma demonstrated the highest rate and haemangioma demonstrated the lowest rate of Doppler signals from within the lesions. To differentiate malignancy from haemangioma, the presence or absence of Doppler signals from these lesions were used as criteria. The specificity and positive predictive value were very high (100%, 100%), but the sensitivity, negative predictive value and accuracy were low (61.5%, 48.3%, 71.7%, respectively). With one exception, all lesions measuring less than 3 cm in diameter with detectable Doppler signals were hepatocellular carcinoma. Using these results it is possible to differentiate hepatocellular carcinoma from metastases and haemangioma with high sensitivity, specificity, positive and negative predictive value, and accuracy (80.8%, 96.4%, 95.5%, 84.4%, 88.9%, respectively, for metastases; 80.8%, 100%. 100%, 81.5%, 89.6%, respectively, for haemangioma). We conclude that Doppler signals from within a lesion in combination with its size can aid differentiation of hepatocellular carcinoma from two other kinds of common hepatic tumour.

Hemodynamic assessment of vascular malformations by angio CT with generation of functional transit time images

We performed a CT dynamic study during the first pass of an intravenously injected bolus of a iodinated contrast medium, followed by generation of the regional arm-brain circulation time (rABCT) image, in 11 patients with vascular malformations. All lesions could be detected as changes of rABCT, and the comparison with values of normal arteries and veins allowed the deduction of the hemodynamic conditions of the lesions. Seven cases showed evidence of altered distribution of rABCT in the corresponding brain hemisphere, suggesting a perfusion reserve impairment.

Diffuse neonatal hemangiomatosis: imaging findings in two patients

Diffuse neonatal hemangiomatosis is a rare condition in which cutaneous and visceral hemangiomas may coexist. Intra-abdominal involvement occurs commonly and, if untreated, may result in high-output cardiac failure and other life-threatening conditions. We report two neonates with this disease and discuss the radiographic findings and the role of vascular embolization in the treatment of hepatic hemangiomatosis.

Infantile hepatic hemangioma: Doppler US

The duplex Doppler ultrasound (US) characteristics of 13 infantile hepatic hemangiomas were reviewed to assess the utility of these characteristics in diagnosis and follow-up. Clinical correlation was available for all children, with a histologic diagnosis established in three. A variety of tumoral flow patterns were demonstrated, including arterial and venous signals with high-frequency shifts, arteries with little systolic-diastolic flow variation, and low-frequency arterial and venous signals. Follow-up studies in 12 infants documented slower flow within the tumors; one child underwent immediate surgery without follow-up examination. The Doppler US characteristics of infantile liver hemangiomas are variable and overlap with those described in the literature for malignant tumors. Doppler US is most useful in follow-up by allowing monitoring of changes in flow within tumors after therapeutic embolization or conservative management.

[Case report of angiomyolipoma of the posterior upper mediastinum]

A case of posterior upper mediastinal angiomyolipoma is reported. The patient was an asymptomatic 63-year-old female, in whom an abnormal shadow was detected on chest x-ray at medical examination. On computed tomogram, the mass was located in the right paravertebral upper mediastinum, and its density had a CT-number of 12. It had high MRI intensity. Since there remained a possibility of malignancy, thoracotomy was carried out. The resected tumor was soft in consistency and the size was 20 x 23 x 37 mm. Histological examination showed that the mass was composed of fatty tissue, smooth muscle, and vascular tissue. Therefore, the tumor was diagnosed as angiomyolipoma. Although angiomyolipomas are often found in the kidney, those in the mediastinum are very rare and there have been only 2 cases reported in the literature. We consider that angiomyolipoma is rare, but important in the differential diagnosis of mediastinal tumors.

Hyalinized hemangioma of the liver

We report the case of a 65-yr-old woman with hyalinized hemangioma of the liver which, on radiological examination, resembled primary or metastatic carcinoma of the liver. She had undergone a partial colectomy for a sigmoid adenocarcinoma, followed by the diagnosis of a hepatic tumor with ultrasonic echogram 5 months later. The tumor was depicted as a low-density mass on plain computed tomography (CT), and an enhancement at the peripheral portion was noted by contrast CT. Hepatic angiography disclosed a faint pooling of contrast medium in segment 8. A subsementectomy of the liver was performed under the diagnosis of metastatic adenocarcinoma or hepatocellular carcinoma. Histologically, the tumor was composed of dense collagenous tissues with marked hyalinization and scattered sclerotic vessels. Elastic fibers were distributed concentrically around the vessels. Totally hyalinized sclerosis of hemangioma is uncommon, and can be erroneously diagnosed as carcinoma by radiologic examination. This unusual hemangioma is reported, with pertinent literature.