Assessing osseointegration of metallic implants with boronized surface treatment.

BACKGROUND: Modification of endosteal implants through surface treatments have been investigated to improve osseointegration. Boronization has demonstrated favorable mechanical properties, but limited studies have assessed translational, in vivo outcomes. This study investigated the effect of implant surface boronization on bone healing. MATERIAL AND METHODS: Two implant surface roughness profiles (acid etched, machined) in CP titanium (type II) alloy implants were boronized by solid-state diffusion until 10-15µm boron coating was achieved. The surface-treated implants were placed bilaterally into 5 adult sheep ilia for three and six weeks. Four implant groups were tested: boronized machined (BM), boronized acid-etched (BAA), control machined (CM), and control acid-etched (CAA). Osseointegration was quantified by calculating bone to implant contact (BIC) and bone area fraction occupancy (BAFO). RESULTS: Both implant types treated with boronization had BIC values not statistically different from machined control implants at t=3 weeks, and significantly less than acid-etched control (p<0.02). BAFO values were not statistically different for all 3-week groups except machined control (significantly less at p <0.02). BAFO had a significant downward trend from 3 to 6 weeks in both boronized implant types (p<0.03) while both control implant types had significant increases in BIC and BAFO from 3 to 6 weeks. CONCLUSIONS: Non-decalcified histology depicted intramembranous-like healing/remodeling in bone for controls, but an absence of this dynamic process in bone for boronized implants. These findings are inconsistent with in vitro work describing bone regenerative properties of elemental Boron and suggests that effects of boron on in vivo bone healing warrant further investigation.

Case report: Liposarcoma of the sinonasal tract.

Nasal and paranasal malignant tumours account for less than 5% of all head and neck malignancies. Epithelial malignancies overwhelmingly predominate, with squamous cell carcinomas representing the most frequent histological subtype in this location. Soft-tissue sarcomas of the nasal cavity and paranasal sinuses are exceedingly rare. Here, we report two cases of myxoid liposarcomas that occurred in the nasal and paranasal regions, both of which presented diagnostic challenges and could not be diagnosed definitively from intraoperative frozen sections. These cases reinforce the notion that, while they are uncommon, sarcomas in general and liposarcomas in particular should still be considered as part of the differential diagnosis in patients presenting with obstructive symptoms in the nasal and paranasal sinuses.

Tumor-associated hemorrhage in patients with acoustic neuroma.

OBJECTIVE: To describe the clinical significance of tumor-associated hemorrhage in patients with acoustic neuromas. STUDY DESIGN: Retrospective chart review. SETTING: University-based, tertiary care teaching hospital. PATIENTS: Three patients with acoustic neuromas who experienced symptomatic tumoral bleeding. INTERVENTIONS: Radiographic imaging, surgical removal of tumors, and pathologic analysis. MAIN OUTCOME MEASURES: Patient histories, radiologic characteristics, surgical results, and pathologic findings. RESULTS: Tumoral hemorrhage can occur in patients with acoustic neuromas. These three cases and a review of the world literature suggest that tumor size may be the most important risk factor for tumor-related hemorrhage. CONCLUSION: These findings have implications for those patients with acoustic neuromas who choose not to have surgical removal.

Microsurgical treatment of infratentorial malformations.

The brain stem has long lost the designation of "no-man's land." Armed with a detailed knowledge of skull base and parenchymal neuroanatomy, coupled with the advances in intraoperative mapping and monitoring, most intrinsic brain stem cavernous malformations can be resected microsurgically. Success continues to depend on proper patient selection, optimal timing, thorough planning, meticulous technique, and completeness of the resection.

Successful living related liver transplantation in an adult with fulminant hepatic failure.

We report a case of an adult female who developed fulminant hepatic failure (FHF) during the second trimester of pregnancy and underwent a successful living related liver transplantation because no cadaveric donor was available during the development of life-threatening symptoms. A left lateral segment hepatic graft was procured from her brother, whose body weight was similar to hers. Her postoperative course was complicated by bleeding at the biliary anastomosis and subsequently by a biliary leak. Nevertheless, the complications were corrected surgically and the patient recovered well with a good quality of life 5 months after the transplant. This case suggests that living related liver transplantation should be considered more frequently for adult FHF patients. As the window of therapeutic opportunity is narrow for the dramatic condition of FHF, wide acceptance of this procedure will be of great benefit for the patients suffering from FHF.

Revascularization and aneurysm surgery: current techniques, indications, and outcome.

Revascularization is an important component of treatment for complex aneurysms that cannot be directly clipped and instead require parent vessel occlusion. A consecutive series of 61 patients with 63 aneurysms requiring cerebral revascularization is presented. Aneurysms were located along the petrous internal carotid artery (ICA) (n = 5), the cavernous ICA (n = 16), the supraclinoid ICA (n = 12), the middle cerebral artery (n = 17), the anterior cerebral artery (n = 4), the vertebral artery/posterior inferior cerebellar artery (n = 5), and the midbasilar artery (n = 4). Aneurysms were treated by direct clipping (n = 8), trapping (n = 28), proximal vessel occlusion (n = 9), distal vessel occlusion (n = 1), excision (n = 15), and thrombotic occlusion (n = 2). Revascularization was performed with petrous to supraclinoid ICA bypass (n = 12), superficial temporal artery to middle cerebral artery bypass (n = 15), superficial temporal artery to middle cerebral artery bypass with saphenous graft (n = 5), superficial temporal artery to superior cerebellar artery bypass (n = 4) long saphenous bypass (n = 11), in situ bypass (n = 3), and primary reanastomosis (n = 13). Fifty-seven patients (93%) had good outcomes, and one patient died (surgical mortality, 2%). This experience demonstrates that revascularization can be performed with low morbidity and mortality. We think that the cumulative risks of not performing revascularization in patients who tolerate ICA balloon occlusion exceed the surgical risk of revascularization. We therefore favor revascularization in patients with complex aneurysms treated by surgical arterial occlusion.

History of brain stem surgery.

The earliest surgical procedures on the brain stem parenchyma were directed at sectioning specific fiber pathways to alleviate pain. Subsequently, some tumors, abscesses, and vascular lesions that displace rather than invade the parenchyma have been successfully removed. Future advances depend on the ability to preserve and restore neural function in operated tissue.

Multiple trauma in the achondroplastic dwarf: an emergency medicine physician perspective case report and literature review.

Although uncommon, the achondroplastic dwarf (AD) may become the victim of multiple trauma, presenting special challenges for the emergency department (ED) physician. Traditional management of airway, breathing, circulation, and neurological disability is altered by the unique anatomic features of achondroplasia. Despite facial abnormalities observed in the AD, orotracheal and nasotracheal intubation are usually accomplished without particular difficulty; however, abnormalities of the base of the skull and cervical spine make hyperextension of the neck especially hazardous in these patients. The lungs are functionally normal, although vital capacity is decreased and thoracic case abnormalities and abdominal obesity impair lung expansion. Vascular access in the AD is difficult. Peripheral access is difficult because of excessive subcutaneous fat, whereas central venous access is complicated by neck, chest wall, and spinal abnormalities that obscure commonly used anatomic landmarks. Major neurological syndromes observed in ADs are hydrocephalus, cervical medullary compression, and thoracolumbar stenosis. The ED physician should recognize these syndromes, their potential to produce neurological disability, and their unique implications for trauma.