The inferior turbinate flap: a novel technique for prosthetic preparation of a total rhinectomy defect.

For total rhinectomy defects, the decision to proceed with a prosthetic versus surgical reconstruction is multifactorial, taking into account patient risk factors, availability of donor tissues, the need for tumor surveillance, and personal preferences. When a prosthetic approach is chosen, the reconstructive surgeon is tasked with preparing the defect to maximize prosthetic retention and prevent ulcerations. Stable bone coverage is critical to achieve this aim. Although skin grafting has been described previously for bone coverage, the periosteum is often stripped. We present a novel use of the inferior turbinate flap for preparation of rhinectomy defects that can be utilized regardless of the presence or absence of the periosteum and provides a more durable coverage than skin grafts.

Impact of transmission of drug-resistant HIV on the course of infection and the treatment success. Data from the German HIV-1 Seroconverter Study.

BACKGROUND: Data on the clinical course of infection in patients with transmitted drug-resistant HIV before and after initiation of treatment are scarce. PATIENTS AND METHODS: Genotypic resistance was analysed in 504 therapy-naïve individuals with a known date of infection. Resistance was predicted using the Stanford algorithm. Clinical parameters for 80 individuals with transmitted drug-resistant HIV and for 424 patients with susceptible virus were analysed. RESULTS: In 16% of the individuals transmitted drug-resistant HIV was found. Detection of drug-resistant HIV was more likely in individuals with acute primary HIV infection [odds ratio (OR)=1.529; 95% confidence interval (95% CI) 1.001; 2.236]. At the time of infection patients with an acute infection with resistant HIV had lower viral loads. CD4 cell counts tended to be higher and the CD4 cell loss more pronounced in the group with resistant HIV. Suppression of the viral load below the detection limit was achieved in 64% of the group with resistant HIV and in 85% of the group with susceptible HIV 6 months after initiation of therapy (P=0.199). The majority of the group with resistant HIV (74%) received at least one compromised drug. CONCLUSION: First-line treatment including drugs with predicted resistance can impair virological success in some patients. Factors influencing the decision to include compromised drugs need to be investigated.

Preoperative assessment for and outcomes of mandibular conservation surgery.

INTRODUCTION: The role of marginal mandibulectomy and other conservative resective procedures for patients with early cortical mandibular invasion from squamous carcinoma of the oral cavity remains poorly defined. The purpose of this retrospective study was to evaluate the efficacy of preoperative assessment for bone invasion and the outcomes of different mandibular resective procedures that preserve mandibular continuity. METHODS: The charts of 222 patients treated at the University of Texas M. D. Anderson Cancer Center between 1960 and 1990 were reviewed. All patients had a biopsy-confirmed diagnosis of squamous carcinoma involving either the lower gingiva, floor of mouth, oral tongue, or retromolar trigone. All patients had a surgical resection that involved removing less than a segment of the mandible. Patient data were analyzed to determine the usefulness of preoperative assessment and outcomes of therapy. RESULTS: Clinical evaluation of mandibular bone invasion was more sensitive than radiologic evaluation, whereas radiologic assessment was more specific and had a higher reliability index. The overall local and regional recurrence and distant metastasis rates for all T stages were 14.4%, 18.0%, and 2.7%, respectively. Sixty-nine point eight percent of all patients were without evidence of disease 2 years after treatment. CONCLUSIONS: Mandibular conservation surgery is oncologically safe for patients with early mandibular invasion. Accurate preoperative assessment that combines clinical examination and radiographic evaluation is better than either modality alone, but clinical judgment is still necessary for proper patient selection.

Lipoinjection in the paralyzed feline vocal fold: study of graft survival.

Six adult domestic strain cats were used to study the long-term histologic outcome of injected autologous fat for augmentation of the paralyzed vocal fold. Each animal had surgically induced left vocal cord paralysis via sectioning of the recurrent laryngeal nerve, followed by injection of 0.1 to 0.2 ml of autologous fat into the paralyzed vocal fold. The animals were killed at 6 weeks, and at 4, 6, 8, and 12 months after the injection. Photographic and videolaryngoscopic data were obtained. Histologic studies of the larynges were performed. The results documented histologic viability and persistence of a portion of the injected adipose tissue graft at 8 months after the injection, but only minimal graft survival at 12 months. The outcome suggests that autologous lipoinjection has potential use for short-term (several months) augmentation of the paralyzed vocal cord. Further investigation is warranted before recommending this technique for such use or as an alternative to currently available long-term injectable laryngeal biomaterials.

A new adhesive bonding material for the cementation of implantable devices in otologic surgery.

BACKGROUND: Presently, there are no U.S. Food and Drug Administration (FDA)-approved adhesive bone cements for the surgical fixation of prosthetic materials in the middle ear. A promising new cement, 4-META/MMA-TBB opaque resin, has shown remarkable adhesive properties as a bone cement in vivo. The cement is composed of 4-methacryloyloxyethyl trimellitate anhydride (4-META) and methyl methacrylate (MMA) as monomers and tri-n-butyl borane (TBB) as an initiator. METHODS: An electromagnetic semiimplantable hearing device presently under development was implanted into the middle ear of six cats using 4-META/MMA-TBB resin to cement a titanium-encased magnet to the incus. The animals were subsequently killed (at a mean of 9.6 months) to assess the (temporal bones and specifically the magnet-incus complex in each animal. RESULTS: The titanium-encapsulated magnet was firmly adherent to all incuses without any failure of the cement-bone interface. Histopathologic examination of the implanted temporal bones demonstrated lack of middle ear inflammation. Transmission electron microscopy of the incuses demonstrated a unique "hybrid layer" in the bone-side subsurface of the bone-cement interface that elucidates the mechanism of interfacial adhesion. CONCLUSIONS: Our investigation highlights the special biomechanical properties as well as the biocompatibility of 4-META/ MMA-TBB resin that make it an attractive bone-bonding agent for use in otologic surgery, including its potential usefulness during ossicular reconstruction.

Effect of magnetic resonance imaging on a new electromagnetic implantable middle ear hearing device.

OBJECTIVE: A 1.5-T magnetic resonance imager has been shown to be contraindicated for use in patients with pacemakers, cochlear implants, and neurostimulators. Our semi-implantable middle ear device uses a new adhesive bone cement. 4-META/MMA-TBB, for cementation of a 29-mg titanium-encased neodymium-iron-boron (NdFeB) magnet to the incus. METHODS: Five NdFeB magnets and four solid titanium cylinders were cemented onto the incus of five preserved human temporal bones and two cadaver heads. They were all inserted into a magnetic resonance imager and evaluated for possible disruption. RESULTS: Owing to the magnetic torque, the three magnets on the temporal bone were disrupted from the incus. The two cylinders on the temporal bones and the two cylinders and two magnets on the whole heads were not affected. The magnetic resonance imaging field did not affect the coercive force of the NdFeB magnets. CONCLUSION: The large torque produced by a magnetic resonance imager may disrupt the magnet-cement and cement-incus interfaces, causing dislodgement. We postulate that patients with implantable magnets on the incus should not undergo magnetic resonance imaging testing.

Metoclopramide enhances the effect of photodynamic therapy on xenografted human squamous cell carcinoma of the head and neck.

OBJECTIVE: Photodynamic therapy (PDT) is a promising new treatment modality for head and neck cancer that is based on the uptake of a systemically administered photosensitizer in tumor tissue and local illumination of the lesion by a high-intensity visible light source, typically a tunable argon-pumped dye laser. We developed a new photosensitizer named silicon phthalocyanine [SiPc(OH) OSi(CH3)2(CH2)3N(CH3)2, abbreviated as SiPc IV], which yields superior PDT responses in vitro and in vivo compared with other clinically used photosensitizers. However, tumor regrowth following SiPc IV-based PDT is still a therapeutic problem. The benzamide derivatives, for example, have been shown to enhance tumor ablation when used during radiotherapy and chemotherapy. Therefore, we used metoclopramide hydrochloride, a benzamide derivative, to evaluate its effects on PDT response. DESIGN: Intradermally injected human squamous cell carcinoma cells were grown to 40 to 80 mm3 in athymic nude mice and irradiated with 675-nm light (75 J/cm2, 75 mW/cm2) 24 hours after the intraperitoneal injection of SiPc IV (1.0 mg/kg). Metoclopramide hydrochloride (2 to 48 mg/kg) was injected intraperitoneally 1 hour before and 24 and 48 hours after irradiation. RESULTS: Tumors exposed to PDT alone showed 80% to 90% tumor regression with regrowth in most animals within 20 days. Tumors treated with metoclopramide hydrochloride (48 mg/kg) plus PDT demonstrated 100% tumor regression without regrowth up to the time of killing (150 days). No observable toxic effects were clinically apparent with the high doses of metoclopramide. CONCLUSIONS: Our results show that administering metoclopramide in combination with PDT may be a promising approach to the management of head and neck cancer.

Biomechanical assessment of a new adhesive bone cement for otologic surgery.

The adhesion of metallic prostheses to bone is a major problem in otologic surgery. Conventional bone cements lack significant adhesive strength, which predisposes the cemented prosthesis to loosening. The advent of surgically implantable hearing devices is one example where an adhesive cement to secure metal to bone would be useful. The biomechanical properties of a new cement, 4-META/MMA-TBB opaque resin, were evaluated in an animal model. The cement is composed of 4-methacryloyloxyethyl trimellitate anhydride (4-META) and methyl methacrylate (MMA) as monomers and tri-n-butyl borane (TBB) as an initiator. Titanium disks were cemented to the tibias of rabbits, which were sacrificed at 0 and 90 days. Tensile and shear bond strengths between bone and metal were tested at both times. The mean baseline tensile and shear bond strengths were 8.92 MPa and 11.96 MPa, respectively. Adhesive failure occurred at the bone-cement interface. The decrease in bond strength at 90 days was minimal. Thus, 4-META/MMA-TBB cement is a promising new metal-to-bone adhesive that may be useful for the surgical fixation of metallic prostheses in otologic surgery.

Contactless semi-implantable electromagnetic middle ear device for the treatment of sensorineural hearing loss. Short-term and long-term animal experiments.

A contactless electromagnetic hearing device has been designed following basic science experiments, improvement of electronics, and precision micromechanics. Different prototypes have been developed and tested in the laboratory, fresh human temporal bones, and acute and chronic animal experimentation. A conductive hearing loss model was first developed in the cat using samarium cobalt as the target magnet. Later, a highly efficient electromagnetic air-core coil was selected to vibrate a neodymium iron boron magnet cemented to the body of the incus and tested in acute and chronic experiments using the cat as the model. In this group of animals, the ossicular chain was left intact. There was no failure of the target magnet, driving coil, or implanted electronics. The only problem encountered in this evaluation was a malfunction of the receiving antenna that had to be redesigned and retrofitted into the implanted units. This system would be suitable for the treatment of moderate to severe sensorineural hearing loss. Planning to begin human clinical trials is ongoing.

A contactless electromagnetic implantable middle ear device for sensorineural hearing loss.

Following basic science experiments, improvement of precision micromechanics and electronics design, and development of different prototypes, a contactless electromagnetic hearing device has been successfully implanted in cats (acute experiments). Chronic animal experiments using the cat as well as the rabbit are ongoing to test the components of the device. A highly efficient air core coil is used to vibrate a neodymium-iron-boron magnet cemented to the body of the incus. The parts of the system, including implanted electronics (hybrid circuit, solid state), are laser welded and hermetically sealed. The system allows for the generation of enough force which vibrates the magnet implanted on the incus. It would be suitable for the treatment of moderate to severe sensorineural hearing loss.

Subacute necrotizing sialadenitis.

Twelve cases of a heretofore unreported minor salivary gland disease have been reported. Although an infectious cause is suspected for this self-limiting inflammatory process, the actual cause remains unknown. It typically presents as a unilateral, erythematous, nonuclerated but painful, solitary firm swelling of the posterior hard palate. Patients are most often young white men who have spent several weeks in a new environment with a group of people living in close quarters such as military barracks.

The role of computed tomography in the evaluation of cemento-osseous lesions.

The role of computed tomography (CT) and CT numbers in the evaluation of fibro-osseous and cementum-containing lesions is discussed. The computed tomographic findings in a case of cemento-ossifying fibroma involving the maxilla and maxillary sinus are presented.

Nodular fasciitis of the orofacial region.

The clinical and histologic findings from a study of forty-one cases of nodular fasciitis occurring in the orofacial region are presented. These findings reveal no essential differences in the biologic conduct of nodular fasciitis, whether it occurs in the orofacial area or in its preferred sites, i.e., the extremities and trunk. Various histologic findings are illustrated, none of which, including central necrosis, are indicative of any adverse biologic behavior. Accumulation of a large series of nodular fasciitis of the orofacial region indicates that this anatomic site is perhaps uncommonly but certainly not rarely affected. Pathologists, therefore, need not be so reluctant, as was found in this study, about assigning the diagnosis of nodular fasciitis to orofacial lesions.