Alexis D. Furze

Biofilm presence in humans with chronic suppurative otitis media

Objective: To study the presence of biofilm formation in humans with chronic suppurative otitis media (CSOM). Study Design: Cross-sectional study. Setting: Tertiary academic hospital. Subjects and Methods: Patients undergoing middle ear surgery between July 2006 and March 2008. Tissue samples were obtained from 25 patients, of which 20 specimens were successfully processed for this study. The remaining samples were not analyzed due to sample damage or loss during preparation. Of the 20 specimens studied, 10 were harvested as the experimental group from patients with CSOM and the other 10 harvested as controls from patients undergoing otologic surgery for acoustic neuroma, cochlear implant, or routine tympanoplasty. Ages ranged from 26 to 74 years (mean 45 yrs). Male-to-female ratio was 2:3. Scanning electron microscopy and confocal laser scanning microscopy were used to identify the presence of biofilms. Live-dead staining was used to assess whether bacteria present were viable. The outcome measured was the presence of adherent biofilms on middle ear mucosa. Results: Biofilms were present in six of 10 samples (60%) from the CSOM group, but only in one of 10 control samples (10%). Comparative analysis revealed a statistically significant difference (P < 0.05) in the presence of biofilms in specimens from the CSOM group versus the control group. Conclusion: Biofilms were statistically more common in patients with CSOM compared with control patients.

Dexamethasone and methylprednisolone do not inhibit neuritic outgrowth while inhibiting outgrowth of fibroblasts from spiral ganglion explants

Conclusion. Dexamethasone and methylprednisolone do not inhibit neuritic outgrowth while inhibiting fibroblastic outgrowth from spiral ganglion micro-explants. Objectives. To demonstrate reduced fibroblastic outgrowth while maintaining neurite outgrowth for several corticosteroids using an in vitro test system of neonatal rat spiral ganglion micro-explants. Materials and methods. The in vitro test system comprised 3-day-old rat spiral ganglion micro-explants. Dexamethasone, methylprednisolone, triamcinolone acetonide, and human recombinant brain-derived neurotrophic factor (hrBDNF) were tested in vitro. The control was ganglion micro-explants in supplemented Dulbeccos modified Eagles medium. Areas of the ganglion explant, neurite and fibroblast outgrowth of ganglion explants after 10 days in vitro were imaged, digitized, and analyzed using Image Tool 3.00 on a PC workstation. Areas of neurite and fibroblast outgrowth from the experimental explants were compared against values obtained from control explants. Results. Dexamethasone gave the best result of the three corticosteroids tested for inhibiting fibroblast outgrowth while not inhibiting neurite outgrowth from the ganglion micro-explants. Media containing hrBDNF (10 ng/ml) stimulated significantly greater neurite outgrowth than outgrowth from control explants (p<0.001). Ganglion micro-explants treated with dexamethasone (0.02 mg/ml) and methylprednisolone (0.5 mg/ml) provided the greatest inhibition of fibroblast outgrowth compared with control explants (p<0.001).

Pathology Case Quiz 2

A 66-YEAR-OLD WOMAN PRESENTED WITH A 2-month history of intermittent rightsided epistaxis. She denied any face or head trauma, blood dyscrasias, contralateral nasal obstruction, diplopia, cranial nerve deficits, overlying cheek skin changes, dysphagia, odynophagia, voice changes, weight loss, fever, or chills. Her medical history was remarkable for hypertension, diabetes, and degenerative joint disease. Her surgical history was notable for a total thyroidectomy. She denied tobacco, alcohol, or drug use. Physical examination revealed a large, obstructing, soft tissue mass located in the right nasal cavity. The left nasal cavity was noted to have normal mucosa, normal-sized turbinates, a mildly deviated nasal septum, and no evidence of abnormal lesions or masses. A coronal computed tomographic scan revealed a soft tissue mass obliterating the right nasal cavity with extension through the cribriform plate into the anterior cranial fossa superiorly and the right orbit medially (Figure 1). T2-weighted magnetic resonance images demonstrated a hyperintense intranasal mass with extension into the extraconal space of the medial right orbit and no involvement of the sphenoid sinus (Figure2). The patient underwent complete surgical excision via a craniofacial resection and a right lateral rhinotomy. Surgical margins were free of tumor. Histologic examination demonstrated a patternless spindle cell proliferation in a prominently collagenized background showing a bland cytologic appearance without nuclear atypia and mitosis. The cells had scant cytoplasm with indistinct borders and dispersed chromatin within vesicular nuclei (Figure 3). The specimen also showed a prominent hemangiopericytoma-like branching vascular pattern and strong immunoreactivity for CD34 (Figure 4). Other immunohistochemical staining revealed that the tumor was positive for CD99, bcl2, and desmin but negative for cytokeratin AE1/AE3, CAM 5.2, epithelial membrane antigen, smooth muscle actin, and S100 protein. What is your diagnosis?

Cochlear implantation in a patient with profound hearing loss with the A1555G mitochondrial DNA mutation and no history of aminoglycoside exposure

The A1555G mitochondrial deoxyribonucleic acid (mtDNA) point mutation has classically been associated with sensorineural hearing loss in patients following aminoglycoside exposure. More recently, the mutation has been implicated in sensorineural hearing loss in patients without previous aminoglycoside use. In addition, cochlear implantation has been shown to be effective in the group of patients with prior aminoglycoside exposure but, to date, no case of cochlear implantation in a patient with the A1555G mutation and no prior exposure to aminoglycosides has been explicitly described in the literature. We report the case of an 80-year-old woman with the A1555G mtDNA mutation, a 35-year history of bilateral progressive hearing loss and no history of aminoglycoside exposure who underwent successful implantation of a Nucleus 24 Contour device at our institution. Post-operatively, the patient exhibited marked improvement in tests of auditory performance. We conclude that cochlear implantation can be an effective method to restore some sense of hearing in patients with the A1555G mtDNA mutation and sensorineural hearing loss.

Comparison of calcium phosphate preparations for onlay cranial augmentation in a murine model

Calcium phosphate preparations are often employed for a variety of reconstructive tasks. The majority of existing data regarding these preparations relates to their use as an inlay implant. The present study aims to evaluate calcium phosphate preparations and their tissue characteristics related to onlay augmentation. Thirty-six research mice were divided into three groups of 12. Each animal underwent onlay augmentation with a calcium phosphate preparation. Group 1 members were subjected to hydroxyapatite (HA) paste while group 2 was treated with beta-tricalcium phosphate granules alone (TCP). Finally, group 3 was treated with a combined mixture of both substances (HA-TCP). The animals were harvested for histological analysis and data collection. Groups 2 (TCP) and 3 (HA-TCP) developed greater osteoneogenesis and tissue integration compared to Group 1 (HA). The results were found to be statistically significant (p < 0.01). Calcium phosphate preparations including TCP alone or in combination with HA undergo greater osteoneogenesis and soft tissue integration compared with hydroxapatite alone when used as an onlay implant in the animal model. Therapeutic study — Level II.