Faculty Bibliography

BACKGROUND: Haemangiomas of the head or face are a frequent vascular pathology, consisting in an embryonic dysplasia that involves the cranial-facial vascular network. Haemangiomas show clinical, morphological, developmental and structural changes during their course. METHODS: The clinical characteristics of head-facial haemagiomas were studied in 28 individuals (9 males and 19 females) admitted in our Hospital. Sixteen of these patients(n = 16) underwent surgery for the removal of the haemangiomas. All the removed tissues were transferred in experimental laboratories for the staining of microanatomical details, somatic and visceral nerve fibres, adrenergic and catecholaminergic nerve fibres. Beta-adrenergic receptors were died with a fluorescent method. All results were submitted to the quantitative analysis of images and statistical evaluation of the data. RESULTS: The morphological results revealed numerous micro-anatomical characteristics of the haemangiomatous vessels. The somatic and visceral nerve fibres were poor and located exclusively in the adventitial layer. There was a marked decrease of adrenergic nerve fibres in the haemangiomatous vessels. The fluorescence of catecholaminergic nerve fibres and the overall area of fluorescent structures were also decreased in haemangiomatous vessels. Beta adrenergic receptors are strongly decreased in haemangiomatous vessels. The morphometrical analysis of images and statistical evaluation of the data confirmed all our experimental results. CONCLUSION: The catecholaminergic innervation of the human haemangiomatous vessels comprises nerve fibres containing the main catecholaminergic neurotransmitters that are sympathetic in nature. These neurotransmitters are closely related to beta-adrenergic receptors. The sympathetic nervous system plays a key role in the control of the vascular bed flow and vascular motility in both normal and haemangiomatous vessels.

BACKGROUND: The management of the mildly to moderately dilated ascending aorta (3.5 to 4.9 cm) in cardiac surgery remains controversial. Therapeutic options have included radical aortic resection with synthetic graft substitution, external aortic reinforcement or wrap, with or without partial aortic wall excision, and a watch-and-wait approach. We reviewed our institutional experience with Dacron (DuPont, Wilmington, DE) mesh wrap support of dilated ascending aortas. METHODS: During the last 20 years, 102 patients with aneurysmal dilatation of the ascending aorta underwent wrapping of the ascending aorta with a fine Dacron mesh from the ventricular-aortic junction to the origin of the innominate artery. For the last 10 years, the wrap was anchored to the aortic annulus with pledgeted sutures. Aortic diameters up to 6 cm, without focal areas of thinning, were wrapped. Aortic diameters exceeding 6 cm, or with focal thinning, underwent tailored aortic wall resection and wrapping. Primary end points of the study included mortality, aortic diameter growth, dissection or rupture, or both. RESULTS: The mean age of the group was 54.7 +/- 19 years (range, 12 to 90 years). A single patient underwent aortic wrapping without cardiopulmonary bypass. Sixty-six patients (65%) required additional aortic valve surgery. Five patients (5%) had reinforcement of dilated sinuses with glutaraldehyde-treated pericardial patches combined with wrapping. Twenty-seven patients (26%) had combined coronary and valve surgery, and 2 patients had coronary revascularization alone. There was neither early nor hospital mortality. Among the 81 patients (79%) we were able to contact, 7 (7%) late deaths had occurred at 0.5, 1, 3, and 9 years after operation that were unrelated to aortic pathology. Various levels of follow-up were obtained in the 88 patients (86.2%). In 78 patients, echocardiograms, computed tomography angiograms, or magnetic resonance angiograms were obtained. In 2 of these patients, aneurysmal dilatation of the sinuses developed below the wrap and reoperation was required. No patient in whom the mesh wrap was anchored to the aortic annulus required reoperation. All 81 patients that were contacted by us and monitored by referring physicians were asymptomatic and free of problems related to the aorta. The mean (+/- SD) preoperative diameter of the ascending aorta was 49.2 +/- 7.8 mm (range, 35 to 87 mm), the postwrap intraoperative diameter was 32.9 +/- 3.4 mm (range, 20 to 40 mm), and the follow-up postoperative aortic diameter was 35.6 +/- 12.7 mm (range, 27 to 52 mm). The mean average change in the aortic diameter during the follow-up period was 2.6 +/- 14.8 mm (range, -7 to 22 mm), a mean of 8%. The mean follow-up period was 5.7 years (median, 4.77 years; range, 9 days to 21 years). There were no infections or other early complications related to the wrap. CONCLUSIONS: Dacron mesh support of the moderately dilated aneurysmal ascending aorta, alone or in conjunction with coronary revascularization, aortic root surgery, or valvular operations, or both, is safe and durable. Dacron mesh is transparent and stretchable, permitting tight girdling of the aorta. These properties prevent hematoma formation, facilitate proximal vein graft anastomoses, and provide visualization and access to aortic suture lines. Finally, this technique retards further aortic dilation, altering the natural history of aortic aneurysms.

BACKGROUND: Free tissue transfer for adult mandibular reconstruction is a well-established technique; however, there are few reports of pediatric microvascular lower jaw reconstruction. METHODS: This retrospective study was undertaken to review the range of indications, choices, safety, and efficacy of pediatric free tissue transfer to the lower jaw. All patients underwent a parascapular, scapular, or fibula free tissue transfer. Flap choice was based on preoperative clinical examination, radiographic findings, need for linear or multiplanar mandibular reconstruction, need for dental restoration, severity of soft-tissue deficit, and peroneal artery anatomy. RESULTS: Over a 10-year period (1989 to 1999), we performed eight free tissue transfers to reconstruct the mandibles of seven children, aged 6 to 17 years. Indications included radiation-induced hypoplasia (n = 1), postsurgical resection of fibrous dysplasia (n = 1), hemifacial microsomia (n = 3), Robin sequence with severe micrognathia (n = 1), and osteomyelitis (n = 1). The authors transferred four parascapular osseocutaneous, two scapular osseocutaneous, one fibular osseocutaneous, and one fibular osseous flap to reconstruct five ramus, four condyle, and two subtotal mandibular defects. All bony defects were successfully bridged and all osseous flaps successfully integrated. Postoperatively, mandibular symmetry and Angle class I occlusion were restored in all patients throughout the 10.5-year follow-up period (range, 9 to 14 years). Two patients received osseointegrated dental implants. Our only complication was the partial loss of a skin paddle. CONCLUSION: Microvascular reconstruction of the pediatric mandible, in selected patients, is a safe, reliable procedure that provides the bone stock and soft tissue necessary to restore normal maxillomandibular growth and dental rehabilitation.

Former Surgeon General David Satcher's report, Oral Health in America, documents the higher burden of oral diseases and conditions borne by those with relatively low social standing at each stage of life. When an entire community suffers from a health concern, that concern becomes a social justice issue. Racial and ethnic minorities, prisoners, and seniors suffer disproportionately from oral diseases and conditions due to societal prejudices that place them at risk over and above any risk associated with their economic means. Community-based delivery models that involve the community in planning and implementation, build upon the existing health safety net to link oral health services with primary care, and change public or institutional policy to support the financing and delivery of oral health care have proven successful. Here we champion the need for a national health plan that includes oral health care to promote social justice and oral health for all.

Mortality after serious systemic thermal injury may be linked to significant increases in cerebral vascular permeability and edema due to blood-brain barrier (BBB) breakdown. This BBB disruption is thought to be mediated by a family of proteolytic enzymes known as matrix metalloproteinases (MMPs). The gelatinases, MMP-2 and MMP-9, digest the endothelial basal lamina of the BBB, which is essential for maintaining BBB integrity. The current study investigated whether disruption of microvascular integrity in a rat thermal injury model is associated with gelatinase expression and activity. Seventy-two adult Sprague-Dawley rats were anesthetized and submerged horizontally, in the supine position, in 100 degrees C (37 degrees C for controls) water for 6 s producing a third-degree burn affecting 60-70% of the total body surface area. Brain edema was detected by calculating water content. Real time PCR, Western blot, and zymography were used to quantify MMP mRNA, protein, and enzyme activity levels. Each group was quantified at 3, 7, 24, and 72 h post thermal injury. Brain water content was significantly increased 7 through 72 h after burn. Expression of brain MMP-9 mRNA was significantly increased as early as 3 h after thermal injury compared to controls, remained at 7 h (p<0.01), and returned to control levels by 24 h. MMP-9 protein levels and enzyme activity began to increase at 7 h and reached significant levels between 7 and 24 h after thermal injury. While MMP-9 protein levels continued to increase significantly through 72 h, enzyme activity returned to control level. The increase in MMP-9 expression and activity, associated with increased BBB permeability following thermal injury, indicates that MMP-9 may contribute to observed cerebral edema in peripheral thermal injury

BACKGROUND: Diabetics suffer from vascular dysfunction with increased risks of coronary artery disease and peripheral vascular disease secondary to an impaired ability to respond to tissue ischemia. Because endothelial progenitor cells are known to home to sites of ischemia and participate in new blood vessel growth, the authors examined the effects of diabetes on human endothelial progenitor cell function and peripheral tissue signaling in hypoxia, and determined whether these cells might be a useful cell-based therapy for diabetic vascular complications. METHODS: Circulating human endothelial progenitor cells from type 2 diabetic patients and controls were isolated and subjected to in vitro adhesion, migration, and proliferation assays (n = 5). Cell mobilization and recruitment were studied in vivo in diabetic and nondiabetic environments (n = 6). Exogenous human diabetic and normal cells were analyzed for therapeutic efficacy in a murine ischemia model (n = 6). RESULTS: Adhesion, migration, and proliferation of human diabetic endothelial progenitor cells in response to hypoxia was significantly reduced compared with controls. In diabetic mice, cell mobilization from the bone marrow and recruitment into ischemic tissue was significantly reduced compared with controls. Normal cells injected systemically as replacement therapy in a diabetic mouse increased but did not normalize ischemic tissue survival. CONCLUSIONS: These findings suggest that diabetes causes defects in both the endothelial progenitor cell and peripheral tissue responses to hypoxia. These changes in endothelial progenitor cell function and signaling offer a novel explanation for the poor clinical outcome of type 2 diabetics following ischemic events. Based on these findings, it is unlikely that endothelial progenitor cell-based cellular therapies will be able to prevent diabetic complications