High-resolution micro-CT for morphologic and quantitative assessment of the sinusoid in human cavernous hemangioma of the liver.

Hepatic sinusoid plays a vital role in human cavernous hemangioma of the liver (CHL), and its morphologic investigation facilitates the understanding of microcirculation mechanism and pathological change of CHL. However, precise anatomical view of the hepatic sinusoid has been limited by the resolution and contrast available from existing imaging techniques. While liver biopsy has traditionally been the reliable method for the assessment of hepatic sinusoids, the invasiveness and sampling error are its inherent limitations. In this study, imaging of CHL samples was performed using in-line phase-contrast imaging (ILPCI) technique with synchrotron radiation. ILPCI allowed clear visualization of soft tissues and revealed structural details that were invisible to conventional radiography. Combining the computed tomography (CT) technique, ILPCI-CT was used to acquire the high-resolution micro-CT images of CHL, and three dimensional (3D) microstructures of hepatic sinusoids were provided for the morphologic depiction and quantitative assessment. Our study demonstrated that ILPCI-CT could substantially improve the radiographic contrast of CHL tissues in vitro with no contrast agent. ILPCI-CT yielded high-resolution micro-CT image of CHL sample at the micron scale, corresponding to information on actual structures revealed at histological section. The 3D visualization provided an excellent view of the hepatic sinusoid. The accurate view of individual hepatic sinusoid was achieved. The valuable morphological parameters of hepatic sinusoids, such as thrombi, diameters, surface areas and volumes, were measured. These parameters were of great importance in the evaluation of CHL, and they provided quantitative descriptors that characterized anatomical properties and pathological features of hepatic sinusoids. The results highlight the high degree of sensitivity of the ILPCI-CT technique and demonstrate the feasibility of accurate visualization of hepatic sinusoids. Moreover, there is a correlation between the CHL and the size or morphology of hepatic sinusoids, which offers a potential use in noninvasive study and analysis of CHL.

Kaposiform hemangioendothelioma arising in the deltoid muscle without the Kasabach-Merritt phenomenon.

Kaposiform hemangioendothelioma (KHE) is a rare tumor that occurs nearly exclusively during infancy and childhood. It has features common to both capillary hemangioma and Kaposi sarcoma and for that reason many terms have been used for these tumors including "Kaposi-like infantile hemangioendothelioma" and "hemangioma with Kaposi sarcoma-like features." KHE typically presents as an ill-defined, red to purple, indurated plaque and is often complicated by the Kasabach-Merritt phenomenon (KMP), a condition of severe thrombocytopenia and consumptive coagulopathy. Knowledge of the radiological findings of this uncommon tumor might be helpful for diagnosis. We present the MRI features of a case of KHE with neither typical skin lesions nor the Kasabach-Merritt phenomenon.

Clinical application of three-dimensional anisotropy contrast magnetic resonance axonography. Technical note.

The utility of three-dimensional anisotropy contrast (3DAC) magnetic resonance (MR) axonography, a method sensitive to neuronal fibers and their directionality, was investigated in the clinical setting using a 3-tesla MR imaging system based on a General Electric Signa platform. The study focused on healthy volunteers and patients with common structural central nervous system disorders, namely chronic infarction, brainstem cavernous hemangioma, supratentorial meningioma, and astrocytoma. Three orthogonal anisotropic diffusion-weighted images were first obtained. Three primary colors were each assigned to a diffusion-weighted image, respectively, and the images were subsequently combined into a single-color image in full-color spectrum (3DAC MR axonography image). Fiber-tract definition in the cerebral peduncle of the midbrain of healthy volunteers showed intersubject variation, with two general patterns recognized: dispersed (60% of cases) and compact (40% of cases). Pathological alterations in the fiber tracts were readily identified in cases involving wallerian degeneration of the pyramidal tract, as illustrated in the cases of chronic infarction. Displacement of major tracts, such as the medial lemniscus or corticospinal tract, as well as fiber directionality, was also easily recognized in cases of mass lesions. As an imaging method uniquely capable of providing information regarding axonal connectivity, 3DAC MR axonography appears to have promising potential for routine clinical application.

Mitochondrial enlargement and crystalloid matrix arrays: distinctive finding in childhood portal hypertension due to cavernous transformation of the portal vein.

Elongated, enlarged mitochondria with crystalloid matrix arrays were discovered in periportal hepatocytes in 11 of 12 children (age 6 to 15 years) with portal hypertension, minimal alterations on light microscopy, and cavernous transformation of the portal vein. Eleven of the children were clinically well before onset of symptoms, one was anemic with megaloblastic bone marrow, and a second had undergone renal transplantation. Minimal findings by light microscopy included slight portal fibrosis (six cases), pericentral venular fibrosis (one case), mild, patchy sinusoidal sclerosis (one case), central venular and sinusoidal dilatation (two cases), and mild hepatocellular lipid accumulation (one case). Four were judged normal by routine histologic examination. Subtle depletion of periportal hepatocellular glycogen was present in six. In 10, subtle striation or granularity of periportal hepatocyte cytoplasm was visible with high-magnification light microscopy. Although similar mitochondria are seen sporadically in hepatocytes in diverse settings, enlarged mitochondria with crystalloid matrix inclusions have not been previously reported as a uniform feature in children with portal hypertension due to cavernous transformation of the portal vein and minimal other hepatic alteration. It is postulated that the mitochondria are adapting in response to an abnormal metabolic milieu created by hemodynamic alterations.

Ultrastructural study of hemangiomas in children.

An electron microscopic study was carried out of different kinds of hemangiomas (capillary, cavernous and combined) in 18 children at the age of two months up to one year. Centers of differently expressed proliferation both of the endothelial cells and pericytes were found. The proliferation was most distinctly expressed in the capillary and cavernous hemangiomas. At the later stages, regressive and involutive changes, presented better in the capillary hemangiomas, were observed. The authors consider that hemangiomas, irrespective of their active cell growth, are tumours with a good prognosis.

Skeletal-extraskeletal angiomatosis. A clinicopathological study of fourteen patients and nosologic considerations.

We reviewed the consultation files of the ARmed Forces Institute of Pathology for 1951 through 1989 and identified fourteen patients who had had skeletal-extraskeletal angiomatosis. Skeletal-extraskeletal angiomatosis was defined as a benign vascular proliferation involving the medullary cavity of bone and at least one other type of tissue. The age of the patients at the time of initial biopsy ranged from nine months to sixty-nine years (average, twenty-two years; median, ten years). Ten of the patients were male and four were female. The presenting signs and symptoms were highly variable; they included pain (four patients), a mass noted at birth (three patients), a painless mass that developed after birth (two patients), both pain and a mass (one patient), a localized deformity of the thoracic spine (one patient), and anemia associated with chronic bleeding of the gastrointestinal tract (one patient); in this last patient, skeletal lesions subsequently were found and biopsied. Skeletal-extraskeletal angiomatosis was an incidental finding in the remaining two patients. Multiple bones were involved in thirteen of the fourteen patients. Histologically, three patterns of lesion could be identified: cavernous lymphangioma (six patients), cavernous hemangioma (six patients), and arteriovenous hemangioma (two patients). Five of the patients died (three of sepsis associated with persistent lesions of angiomatosis and two of unrelated causes); eight of the patients survived but had residual disease, and one survived and had no evidence of residual disease.

An ultrastructural study of cutaneous hemangioma in two chickens.

Cutaneous hemangioma in two laying hens was examined by light and electron microscopy. In close association with capillary and cavernous hemangioma there was a solid cell mass. Ultrastructurally, the cell mass consisted of undifferentiated mesenchymal cells and had an alveolar structure. There were transitional cell types from the alveolar structure to the capillary and cavernous hemangiomas. Hemangiomatous structure may develop from the undifferentiated mesenchymal cells in the solid cell mass.

Cerebral cavernous angioma: a potentially benign condition? Successful treatment in 16 cases.

Cerebral cavernous angioma (cavernoma) has previously been treated by resection for all presentations when surgically resectable. In this retrospective series of 16 cases, it is demonstrated that, for those patients presenting with epilepsy alone, surgery is often unnecessary. Diagnosis can be made radiologically and excellent seizure control can be obtained with medications. In the authors' experience, those cavernomas symptomatic as epilepsy rarely cause major haemorrhage and the need for surgery as prophylaxis against bleeding in this group is unproven.

[Cavernous hemangioma of the spleen with a localized intravascular coagulation syndrome (Kasabach-Merritt syndrome). Ultrastructural study]. / Hemangioma cavernoso del bazo con síndrome de coagulación intravascular localizada (síndrome de Kasabach-Merritt). Estudio ultraestructural.

Haemangioma is the commonest non-malignant tumour of the spleen. Cytopenia and coagulopathy, secondary to cell trapping and coagulation factors consumption inside the haemangioma, respectively. May occasionally occur as accompanying phenomena. A woman is presented who had splenic haemangioma associated with leucopenia and thrombocytopenia along with decrease fibrinogen and prolonged prothrombin time as well as low complement rates. She had massive splenomegaly with portal hypertension, and the partial oxygen pressure values in mesenteric and portal blood were concurrent with the presence of arteriovenous shunts. The leucocyte and platelet count, the serum complement, the fibrinogen rate and the prothrombin time recovered after splenectomy. The cavernous characteristics of the spleen, containing multiple thrombi, were confirmed upon scanning electron microscope examination. The pathophysiology of the cytopenias and clotting factors consumption is discussed, stress being laid on the ultrastructural findings. A review is presented of the clinical aspects, differential diagnosis and treatment.

[Light and electron microscopic study of orbital cavernous hemangioma].

We examined the specimens of tumors from three patients with orbital cavernous hemangioma by light and electron microscopy. The tumors mostly consisted of many vessels of various sizes. A part of the tumor tissues showed irregular vascular inner spaces like sinusoids. Apart from the sinusoid-like vessels, we divided the other vessels into 10 groups at every 100 microns-interval based on the difference of the inner diameter and measured the maximum and minimum width of the media. The average maximum width increased until the inner diameter reached 300-400 microns, while the average minimum width increased until it reached 200-300 microns. In groups with greater inner diameter, the average maximum and average minimum widths were approximately constant. There were three kinds of vessels: vessels of cuboid endothelia, of flat endothelia, and of both cuboid and flat endothelia. The width of media of the vessels having cuboid and flat endothelia was greater than that of the other types of vessels. The lamina densa of endothelia was broken or stratified. Myofibroblast-like cells proliferated among the vessels and could not be distinguished from tumor cells of hemangiopericytoma. These results indicate that smooth muscle cells proliferate by an unknown mechanism and proliferation is associated with changes of endothelia in cavernous hemangioma, and strongly suggest that this tumor is hamartoma.

Blue rubber bleb naevus syndrome.

An autopsy case of blue rubber bleb naevus syndrome (BRB-NS) is reported. There was the usual occurrence of cavernous haemangioma in the skin and intestine and cardiac involvement by a haemangiomatous lesion might have directly led to the patient's death. By light and electron microscopy, all the haemangiomatous lesions examined were cavernous with the exception of the cardiac tumour which was a mixed-vessel (capillary and cavernous) type of a haemangioma. These findings indicate that any vascular tumour-like lesions may occur in BRBNS. The principal combination of haemangiomas in the skin and intestine in BRBNS regardless of their type is the typical feature of this syndrome.

Ultrastructural study of hemangiomas. 4. Cavernous hemangioma of the liver.

Seven cases of cavernous hemangioma of the liver found accidentally at autopsy were studied by electron microscope. The structures of the hemangioma consisted of capillaries and the intervening stromal cells. The endothelial cells contained pinocytotic vesicles, scattered ribosomes, rough endoplasmic reticulum, and Golgi apparatus. A distinct basement membrane was present beneath the endothelial cells, and multilaminated arrangement of the basement membrane was sometimes observed beneath the endothelial cells. The endothelial cells also contained numerous cytoplasmic filaments, but contained sparse specific endothelial granules. The internal elastic lamina was hardly seen at all in the hemangioma. The stromal cells showed typical smooth muscle cells, modified smooth muscle cells, and fibroblast-like cells. Elastic tissue as well as collagen fibers was present within the intervening stroma. Neither adventitia nor nerve fibers were found in the cavernous hemangioma. It is thought that cavernous hemangioma of the liver may be of a hamartomatous nature.

Cavernous hemangioma of the retina. Immunohistochemical and ultrastructural observations.

A 6-month old girl had unilateral leukokoria. Because retinoblastoma could not be excluded, the blind left eye was enucleated. Histopathologically, a total retinal detachment associated with a widespread cavernous hemangioma of the retina and a preretinal membrane were found. The specimen was further examined by immunohistochemistry and electron microscopy to determine the origin of the preretinal membrane and to study the anatomy of the telangiectatic retinal vessels. The preretinal membrane was mostly composed of spindle-shaped cells that demonstrated immunohistochemically the presence of glial fibrillary-acidic protein and showed, ultrastructurally, numerous glial filaments in their cytoplasm. These findings support the view that this membrane was of glial origin. By electron microscopy, the telangiectatic retinal vessels displayed the anatomic features normally encountered in retinal vessels, which accounts for the absence of exudates observed clinically and angiographically in cases of cavernous hemangioma of the retina.

Scanning electron microscopy of a liver cavernous hemangioma.

A 39-year-old female with a large cavernous hemangioma of the liver was successfully treated by ligation of the left hepatic artery. A wedge biopsy specimen of the hemangioma was obtained after the ligation and was examined by scanning electron microscopy. The hemangioma was demarcated from the surrounding normal liver parenchyma and had a labyrinth of caves 50-150 microns in diameter. The caves were separated by fibrous septa 20-40 microns in width. Endothelial cells of the caves were spindle-shaped and arranged in parallel. The surface property of the caves resembled that of the hepatic artery and differed from that of the portal vein or hepatic vein. These findings support that the cavernous hemangioma of the liver was supplied by the hepatic artery. The labyrinthine structure of the cavernous hemangioma may explain the long standing contrast enhancement of the hemangioma after hepatic arteriography.

Vascular tumors of the mammary gland. A histochemical and ultrastructural study.

A total of five haemangiosarcomata and two benign haemangiomas arising in the mammary gland have been studied electron microscopically and by histochemical techniques. Malignant tumors were mainly composed of endothelial cells reactive to alkaline phosphatase and adenosine triphosphatase, and of pericytes and undifferentiated mesenchymal elements. A juvenile haemangioma showed a more structured wall with an increase of endoplasmic reticulum and filaments, and a diminution of membrane modulations and rod-like tubular bodies. A cavernous haemangioma showed an ultrastructure very similar to normal vessels. The ultrastructural and histochemical data suggest a blood vessel origin of mammary angiosarcomas and show that vascular neoplasms of the breast, benign or malignant, are composed of a combined proliferation of the different cell types present in the vessel wall, as described in other organs.

Histogenesis of hemangiomas--an ultrastructural study on capillary and cavernous hemangiomas of the skin.

13 capillary hemangiomas of the skin were examined by electron microscopy in order to elucidate their histogenesis. The findings show that the histogenetic development of hemangiomas is similar to that of embryonal and fetal capillaries. Initially the undifferentiated angioblastic anlage gives rise to solid buds, which subsequently receive a lumen, thus turning into primitive capillaries. This developmental stage corresponds to early embryonic vasculogenesis. The growth of angiomas is mainly due to sprouting, which as in fetal and postnatal vasculogenesis takes place from both primitive and mature capillaries. These findings support the classical theories on the histogenesis of angiomas (angioblastic and sprouting theories). The question whether in all cases hemangiomas have to pass through all developmental stages or whether it is possible that part of them develops directly from the normal capillary network of the skin by a process of sprouting remains open to discussion. Finally the findings in one cavernous hemangioma and two tele-angiectasias were compared and discussed.

Massive intestinal bleeding in hemangiomatosis of the duodenum.

A 33-year-old male was admitted to Takano Hospital with fainting spell and diaphoresis due to massive terry stool. He had been working and in good health until 2 days before admission. Urgent duodenal endoscopy disclosed hemorrhage from an angiomatous lesion of the duodenum. A duodenal resection with duodenojejunostomy was performed. Pathologic examination revealed a cavernous hemangiomatosis of the duodenum. The patient had a good postoperative course. Hemangioma of the intestinal tract is rare. To our knowledge, the present case is the first case in which urgent endoscopy has succeeded in establishing the preoperative diagnosis of this lesion and ascertaining the bleeding point.

Cavernous hemangioma of the superior mediastinum. Report of a case with electron microscopy and computerized tomography.

An unusual case of cavernous hemangioma of the superior mediastinum in a 38-year-old male is presented. Mediastinal hemangiomas occur more often in children and are usually localized in the anterior-superior compartment in all age groups. Slow expansile growth, lack of infiltration of adjacent structures and microscopically mature cellular elements clearly marked the benign nature of the lesion. Vascular mesenchymal tumors in this location must be approached with caution because of the risks of hemorrhage or local infiltration of vital structures. Electron microscopy revealed active endothelial cells, smooth muscle cells, and intercellular matrix components suggestive of smooth muscle cell origin. Computerized tomography delineated the lesion clearly and demonstrated identical densities for the mass and adjacent blood vessels.

Ultrastructural comparison of capillary and cavernous hemangiomas of the orbit.

Capillary and cavernous hemangiomas are often grouped together as if they were modulations of the same entity. To clarify this nosologic question, three capillary hemangiomas in children and four cavernous hemangiomas in adults were studied by transmission electron microscopy. The capillary hemangiomas consisted of two variably admixed zones, solid cellular zones and zones with open vascular lumens. However, both zones had similar organization. Each vascular unit was composed of endothelial cells and pericytes, which persisted in a tumor three years after its clinical appearance. Macrophages and degenerating cells were found in the interstitium and may be related to the clinical feature of partial spontaneous regression. The cavernous hemangiomas had much larger lumens, and wider and more heavily collagenized trabeculae. The vascular walls were created by multilaminar smooth muscle cells. Therefore, capillary hemangioma is completely different from cavernous hemangioma, which resembles a venous tumor.