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Purpose: To correlate the pathologic findings of cavernous hemangiomas with enhancement patterns seen at dynamic computed tomography (CT) performed after injection of contrast material., Materials and Methods: Sixteen patients underwent dynamic CT followed by hepatectomy. Resected specimens of 16 cavernous hemangiomas, which ranged from 2 to 15 cm in diameter, were obtained. The average size of vascular spaces in the histologic specimen was correlated with their appearance on dynamic CT scans., Results: In 11 tumors, characteristic progressive fill-in after peripheral contrast enhancement was seen (type 1). In type 1 tumors, three zones were noted within the tumor: areas of peripheral puddling in the arterial-dominant phase, areas of gradual fill-in, and areas of no or minimal enhancement. Vascular spaces in areas of peripheral global enhancement were significantly smaller than those in areas of gradual fill-in (P = .03). In areas of no or minimal enhancement, extensive scar tissue (n = 9) or cystic cavity (n = 3) was seen. In three hemangiomas smaller than 3 cm, enhancement occurred diffusely in the arterial-dominant phase and vascular space was small (type 2). In two tumors, enhancement was seen only in the periphery of the tumor (type 3), and the majority of tumor was occupied by the cystic cavity or scar tissue., Conclusion: Dynamic enhancement patterns of cavernous hemangiomas are related to the collective size of their constituent vascular spaces.

Purpose: To characterize the appearance of hemagiomas at two-phase dynamic incremental computed tomography (CT) and to determine the cause of contrast material enhancement of adjacent parenchyma in the first series., Materials and Methods: Contrast-enhanced CT images of 51 hemangiomas in 20 patients were reviewed. Enhancement patterns of hemangiomas in the first series were classified as homogeneous high, peripheral high, and low attenuation; in the second series, as homogeneous high, peripheral high, iso-, and low attenuation. Correlations between arterioportal shunts and early parenchymal enhancement were evaluated in 45 hemangiomas in the 17 patients who underwent angiography., Results: Thirty-two hemangiomas progressively became enhanced. Four had low and eight had homogeneous high attenuation in both series. Seven changed from homogeneous high to isoattenuation. Early parenchymal enhancement was well correlated with presence of arterioportal shunt., Conclusion: Low-attenuation hemangiomas and those that changed from homogeneous high to isoattenuation are atypical and difficult to differentiate from other neoplasms. Most early parenchymal enhancement is caused by associated arterioportal shunts.

Purpose: To determine whether change in size is a characteristic of cavernous hemangioma of the liver., Materials and Methods: Twenty-one focal masses in 21 patients were diagnosed as cavernous hemangiomas with imaging-guided percutaneous fine-needle biopsy performed between 2 weeks and 2 months after initial imaging study (computed tomography [CT] or ultrasonography [US]). Follow-up imaging examinations (CT, US, or magnetic resonance imaging plus US) were obtained at 5-84 months in all patients., Results: The cavernous hemangiomas ranged in size from 1.5 to 13.5 cm. At follow-up imaging, 19 (90%) of 21 lesions had not changed in size; the two remaining lesions increased by 1 and 2 cm over 3 and 10 months, respectively., Conclusion: The size of the majority of cavernous hemangiomas remains stable for periods of follow-up ranging from 5 to 84 months. Growth of these lesions is not characteristic and, when it occurs, should prompt reassessment of the diagnosis.

Many hepatic hemangiomas are discovered incidentally during incremental dynamic bolus computed tomography (CT). To meet the established criteria for diagnosis with CT, however, a second CT examination with single-level dynamic bolus imaging is necessary. A prospective evaluation was performed to examine a simple sign that may be used to diagnose cavernous hemangiomas during incremental dynamic bolus CT. This sign is the visualization of foci of globular enhancement within the hemangioma, analogous to areas of puddling of contrast material seen at angiography. A total of 34 lesions in 21 patients demonstrated foci of globular enhancement. Of the 34 lesions, 32 (94%) proved to be hemangiomas. All 21 patients underwent confirmatory evaluation. Foci of globular enhancement seen during dynamic bolus CT are a strong indication that the lesion is a cavernous hemangioma. This diagnostic sign may obviate further, more expensive imaging studies.

Twelve cases of hepatic hemangioma were examined by computed tomography (CT). Dense accumulations of rapidly injected contrast material in or near the periphery of the lesions were demonstrated in early postcontrast scans. They invaded the area of low density and diminished in attenuation value with time. This marked decrease of the low density area noticed in the precontrast scan was also seen in the later postcontrast scan. These findings were recognized in all 10 cases of hemangioma examined with contrast enhancement, while no cases of hepatoma showed such a peripheral high density zone. Most hepatic hemangiomas could be correctly diagnosed by CT alone.

Fifteen patients with liver masses detected with imaging were strongly considered clinically to have malignant disease. In each case, the possibility of a hepatic cavernous hemangioma was raised upon review of the images. With use of a 20-gauge Franseen needle, a percutaneous hepatic biopsy was performed in all 15 cases, and the diagnosis of cavernous hemangioma was confirmed. There were no complications from the biopsy. Twelve biopsies were performed on an outpatient basis. On the basis of the biopsy results, the care and treatment of each patient were significantly altered. When imaging data are not sufficient to determine that a liver mass is benign, even if the possibility of cavernous hemangioma is entertained, a percutaneous biopsy can be safely performed and can yield a specific histologic diagnosis.

Cavernous hemangioma is the most common benign tumor of the liver. Eighteen patients were studied by both computed tomography (CT) and angiography. The angiographic features were classic, consisting of normal hepatic arteries, no tumor vessels, and densely stained blood-filled spaces producing a "cotton-wool" appearance. Before contrast infusion, CT scans showed roughly spherical, well-demarcated low-density masses; afterward there was a peripheral zone of enhancement which varied in thickness and sometimes had a corrugated inner margin, though the center remained low in density and the overall size of the lesion did not change. The authors feel that the CT findings are characteristic and that in some cases angiography is unnecessary.

Two cases of pediatric blue rubber bleb nevus syndrome are reported. The main features of the disease are rubbery blue cutaneous nevi and hemangiomatous, frequently hemorrhagic malformations of the bowel wall. Polypoid filling defects were seen throughout the bowel on barium studies. This entity should be considered in the differential diagnosis of polyposis, and the skin should be carefully examined for nevi when multiple bowel polyps are demonstrated, especially in patients with gastrointestinal bleeding.

The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma.

Sixteen portal cavernomas were examined with dynamic computed tomography (CT) and confirmed by sonography. Characteristic features included loss of the normal vascular structure and the presence of sinuous collateral pathways which were enhanced during the portal phase. Fifteen patients exhibited transient differences in hepatic attenuation and peripheral arterial concentration of contrast material. Increased arterial flow in the poorly perfused territories is suggested as a cause of these hemokinetic abnormalities.

In hepatic tumors seen in children, treatment and prognosis differ from tumor to tumor and thus accurate determination of their extent and characteristics is important. Evaluation by gray scale ultrasonography, radionuclide imaging and angiography has produced definable characteristics for the various tumor types and often allows distinction from other intrahepatic processes. In addition, chemotherapeutic treatment of initially unresectable malignant hepatic tumors can be followed by nuclear imaging, ultrasound and angiography to determine therapeutic response.

To determine the accuracy of magnetic resonance (MR) imaging relative to computed tomography (CT) in the diagnosis of liver metastases, a randomized, controlled study was conducted of 135 subjects, including 57 with cancer metastatic to the liver, 27 with benign cysts or hemangiomas, and 51 without focal liver disease. The sensitivity of MR imaging for detecting individual metastatic deposits was 64%, significantly greater than 51% for CT (P less than .001); the difference in sensitivity for identifying patients with one or more hepatic metastases was less (82% for MR imaging vs. 80% for CT). In patients without hepatic metastases, the specificity of MR imaging was 99% versus 94% for CT. Significant differences were found between individual MR pulse sequences in detection of individual lesions. The sensitivity of both T1-weighted spin-echo (SE) (64%) and inversion-recovery (IR) (65%) pulse sequences was significantly (P less than .001) greater than either the TE (echo time) 60 msec (43%) or TE 120 msec (43%) T2-weighted pulse sequences. Overall, the accuracy of a single T1-weighted (10-minute) pulse sequence was superior to that of contrast-enhanced CT.

Large, infiltrative cavernous hemangiomas of the distal colon were present in 3 children with the Klippel-Trenaunay syndrome, 2 of whom are the subject of this report. The lesion is manifested clinically as intermittent rectal bleeding starting in the first 5 years of life. The radiographic features include (a) varicose lesions in the wall of the rectosigmoid, ranging from a network of distended submucosal veins to nodular defects, (b) narrowing of the rectum by the surrounding extramural portion of the hemangioma, and (c) phleboliths within the lesion. Inferior mesenteric angiography and sigmoidoscopy are useful for preoperative confirmation. The occurrence of visceral hemangiomas in the Klippel-Trenaunay syndrome and its relevant diagnostic and therapeutic implications are discussed.

Fifty-three orbital lesions of various types were studied by computer tomography to assess the capabilities and limitations of this technique. Although CT scanning in ophthalmology is in its infancy, results showed that it is useful in the investigation of a number of pathological conditions, including congenital anomalies, arteriovenous malformations, bone lesions, trauma, inflammation, granulomas, pseudotumors, epidermoid cysts, and tumors arising in or near the optic nerve, behind the optic bulb, or in the lacrimal region, as well as changes following eye surgery.

Thirty-nine cases of intracranial vascular malformations in children were reviewed. All patients underwent preoperative computed tomography (CT) and 35 had complete preoperative angiographic work-ups. The CT features of intracranial vascular malformations in children are described. Among the 39 patients, there were 30 parenchymal arteriovenous malformations, four dural arteriovenous malformations, three cavernous angiomas, and two venous angiomas. Combined CT and angiography allowed a highly specific diagnosis in 77% of the cases.

Intracerebral venous angioma is a rare congenital vascular malformation of the brain. Three cases are reported, all of which had strikingly similar angiographic findings in the venous phase, viz., a local network of small medullary veins which converge centrally into a single large venous channel which courses transcerebrally to reach the superficial venous system. No gross abnormalities are seen in the arterial phase with the usual techniques. However, magnification delineated enlarged arterial branches supplying the periphery of the malformation in 2 of the 3 cases. A poorly marginated homogeneous blush and early filling of the draining veins were also seen in these 2 patients. The findings in the venous phase agree with those described in previous isolated case reports and appear to be highly suggestive of this rare malformation.

The appearance of focal hepatic lesions on 99mTc-sulfur colloid images is nonspecific. As it is important to distinguish hemangiomas from other lesions prior to biopsy, a prospective study was performed using 99mTc-labeled red blood cells. Dynamic perfusion and delayed blood-pool images (1-2 hours) were obtained and lesion activity categorized as increased, equal, or decreased compared with the liver. Of 21 patients studied, 9 (43%) had one or more hepatic hemangiomas, and 8 of these 9 patients (89%) demonstrated increased blood-pool activity. The 12 nonhemangiomatous lesions consisted of 7 metastatic tumors, 2 hepatomas, 1 cirrhotic nodule, and 2 hepatic cysts. None of these 12 patients had increased activity on delayed blood-pool images. Early dynamic images of hepatic hemangiomas demonstrated variable activity (vascularity) and were not useful in differentiating hemangiomas from other lesions. Sensitivity was 89% and specificity 100%. Although liver enzymes are usually normal with hepatic hemangiomas, they may also be normal in metastatic disease. The authors recommend that delayed blood-pool imaging be performed prior to biopsy, particularly in patients without a known primary tumor or those with normal liver enzyme levels.

Using a 0.35-T superconducting magnet and spin echo imaging, we prospectively evaluated 11 patients who had proved hepatic cavernous hemangioma. Magnetic resonance (MR) identified more lesions than either contrast-enhanced CT, or ultrasonography. The MR appearance was consistent; hemangiomas were homogeneous and generally isointense at short TR and TE intervals but were hyperintense at long TR intervals and greatly hyperintense at long TR and long TE intervals. However, the MR appearance of hemangioma was not specific; 2/14 other focal hepatic masses had similar features. The calculated relaxation times (T1, T2) were not useful in lesion characterization, although the intensity ratio of hemangioma to normal liver at the TR = 2.0 sec TE = 56 msec pulse sequence was useful in diagnosis since hemangiomas always had a ratio greater than 1.4.

Gray-scale ultrasonography and angiography were performed on 5 patients with cavernous hemangioma of the liver. Four patients also had radionuclide scans and 2 had computed tomography. Angiography was the most specific diagnostic examination; the findings of the other 3 techniques were nonspecific, yet valuable for initial identification of the lesions and their characterization as solid tumors.

Five patients with renal cell carcinoma were noted at angiography to have vascular hepatic lesions which resembled metastatic renal cell carcinoma but which proved to be benign hepatic hemangiomas. The angiographic differentiation between small hemangiomas and metastatic vascular neoplasms of the liver can be difficult; angiographic characteristics may not be definitive. Surgery to remove the renal tumor should not be deferred solely on the basis of vascular hepatic lesions found at angiography.

A case of intracranial cavernous hemangioma displaying feeding arteries, tumor stains, and venous pools is presented. Tumors of this type may simulate avascular masses on angiography; however, when surgically excised, they bleed profusely. A correct preoperative diagnosis can help avoid unnecessary incisions. Prolonged injection angiography clearly depicts the tumors and their venous pools, which may be pathognomonic of cavernous hemangiomas.

The roles of single-photon emission computed tomography (SPECT) and planar imaging with technetium-99m-labeled red blood cells in the diagnosis of cavernous hemangioma of the liver were evaluated. The study group consisted of 26 consecutive patients referred for evaluation of liver lesions. A total of 23 cavernous hemangiomas were found, all of which showed decreased or normal flow and delayed uptake of the radiotracer. SPECT demonstrated 13 hemangiomas that were not detected with planar imaging; both modalities demonstrated the other ten lesions. Lesions that were not cavernous hemangiomas showed either normal (n = 6) or increased (n = 4) flow; none had delayed increased uptake on either planar or SPECT images. SPECT with labeled red blood cells is an accurate method for the detection of cavernous hemangiomas of the liver and is more sensitive than planar imaging in depicting small lesions.