title: Head-facial hemangiomas studied with scanning electron microscopy.
abstract: BACKGROUND
  Hemangiomas of the head or face are a frequent vascular pathology, consisting in an embryonic dysplasia that involves the cranial-facial vascular network. Hemangiomas show clinical, morphological, developmental, and structural changes during their course.
  
  
  METHODS
  Morphological, structural, ultrastructural, and clinical characteristics of head-facial hemangiomas were studied in 28 patients admitted in our hospital. Nineteen of these patients underwent surgery for the removal of the hemangiomas, whereas 9 patients were not operated on. All the removed tissues were transferred in our laboratories for the morphological staining. Light microscopy, transmission electron microscopy, and scanning electron microscopy techniques were used for the observation of all microanatomical details. All patients were studied for a clinical diagnosis, and many were subjected to surgical therapy.
  
  
  RESULTS
  The morphological results revealed numerous microanatomical characteristics of the hemangiomatous vessels. The observation by light microscopy shows the afferent and the efferent vessels for every microhemangioma. All the layers of the arterial wall are uneven. The lumen of the arteriole is entirely used by a blood clot. The observation by transmission electron microscopy shows that it was impossible to see the limits of the different layers (endothelium, medial layer, and adventitia) in the whole wall of the vessels. Moreover, both the muscular and elastic components are disarranged and replaced with connective tissue. The observation by scanning electron microscopy shows that the corrosion cast of the hemangioma offers 3 periods of filling: initially with partial filling of the arteriolar and of the whole cast, intermediate with the entire filling of the whole cast (including arteriole and venule), and a last period with a partial emptying of the arteriolar and whole cast while the venule remains totally injected with resin.
  
  
  CONCLUSIONS
  Our morphological results can be useful to clinicians for a precise diagnosis on the aftereffects of hemangiomas.
authors.affiliation: Departments of Anatomy, University La Sapienza, Rome 50-00161, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Cavallotti
authors.forename: Chiara
authors.initials: C
authors.lastname: Cavallotti
authors.forename: Filippo
authors.initials: F
authors.lastname: Giovannetti
authors.forename: Giorgio
authors.initials: G
authors.lastname: Iannetti
mesh_terms: D000328:Adult; D000368:Aged; D016319:Corrosion Casting; D005260:Female; D006258:Head and Neck Neoplasms / Q000473:pathology / Q000648:ultrastructure*; D006391:Hemangioma / Q000473:pathology / Q000648:ultrastructure*; D006801:Humans; D008297:Male; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D008875:Middle Aged; D016612:Paraffin Embedding