In Vivo Optical Characterization of Middle Ear Effusions and Biofilms During Otitis Media.

Otitis media (OM), a common ear infection, is characterized by the presence of an accumulated middle ear effusion (MEE) in a normally air-filled middle ear cavity. While assessing the MEE plays a critical role in the overall management of OM, identifying and examining the MEE is challenging with the current diagnostic tools since the MEE is located behind the semi-opaque eardrum. The objective of this cross-sectional, observational study is to non-invasively visualize and characterize MEEs and bacterial biofilms in the middle ear. A portable, handheld, otoscope-integrated optical coherence tomography (OCT) system combined with novel analytical methods has been developed. In vivo middle ear OCT images were acquired from 53 pediatric subjects (average age of 3.9 years; all awake during OCT imaging) diagnosed with OM and undergoing a surgical procedure (ear tube surgery) to aspirate the MEE and aerate the middle ear. In vivo middle ear OCT acquired prior to the surgery was compared with OCT of the freshly extracted MEEs, clinical diagnosis, and post-operative evaluations. Among the subjects who were identified with the presence of MEEs, 89.6% showed the presence of the TM-adherent biofilm in in vivo OCT. This study provides an atlas of middle ear OCT images exhibiting a range of depth-resolved MEE features, which can only be visualized and assessed non-invasively through OCT. Quantitative metrics of OCT images acquired prior to the surgery were statistically correlated with surgical evaluations of MEEs. Measurements of MEE characteristics will provide new readily available information that can lead to improved diagnosis and management strategies for the highly prevalent OM in children.

Direct Analysis of Pathogenic Structures Affixed to the Tympanic Membrane during Chronic Otitis Media.

Objective To characterize otitis media-associated structures affixed to the mucosal surface of the tympanic membrane (TM) in vivo and in surgically recovered in vitro samples. Study Design Prospective case series without comparison. Setting Outpatient surgical care center. Subjects and Methods Forty pediatric subjects scheduled for tympanostomy tube placement surgery were imaged intraoperatively under general anesthesia. Postmyringotomy, a portable optical coherence tomography (OCT) imaging system assessed for the presence of any biofilm affixed to the mucosal surface of the TM. Samples of suspected microbial infection-related structures were collected through the myringotomy incision. The sampled site was subsequently reimaged with OCT to confirm collection from the original image site on the TM. In vitro analysis based on confocal laser scanning microscope (CLSM) images of fluorescence in situ hybridization-tagged samples and polymerase chain reaction (PCR) provided microbiological characterization and verification of biofilm activity. Results OCT imaging was achieved for 38 of 40 subjects (95%). Images from 38 of 38 (100%) of subjects observed with OCT showed the presence of additional microbial infection-related structures. Thirty-four samples were collected from these 38 subjects. CLSM images provided evidence of clustered bacteria in 32 of 33 (97%) of samples. PCR detected the presence of active bacterial DNA signatures in 20 of 31 (65%) of samples. Conclusion PCR and CLSM analysis of fluorescence in situ hybridization-stained samples validates the presence of active bacteria that have formed into a middle ear biofilm that extends across the mucosal layer of the TM. OCT can rapidly and noninvasively identify middle ear biofilms in subjects with severe and persistent cases of otitis media.

Noninvasive in vivo optical coherence tomography tracking of chronic otitis media in pediatric subjects after surgical intervention.

In an institutional review board-approved study, 25 pediatric subjects diagnosed with chronic or recurrent otitis media were observed over a period of six months with optical coherence tomography (OCT). Subjects were followed throughout their treatment at the initial patient evaluation and preoperative consultation, surgery (intraoperative imaging), and postoperative follow-up, followed by an additional six months of records-based observation. At each time point, the tympanic membrane (at the light reflex region) and directly adjacent middle-ear cavity were observed in vivo with a handheld OCT probe and portable system. Imaging results were compared with clinical outcomes to correlate the clearance of symptoms in relation to changes in the image-based features of infection. OCT images of most all participants showed the presence of additional infection-related biofilm structures during their initial consultation visit and similarly for subjects imaged intraoperatively before myringotomy. Subjects with successful treatment (no recurrence of infectious symptoms) had no additional structures visible in OCT images during the postoperative visit. OCT image findings suggest surgical intervention consisting of myringotomy and tympanostomy tube placement provides a means to clear the middle ear of infection-related components, including middle-ear fluid and biofilms. Furthermore, OCT was demonstrated as a rapid diagnostic tool to prospectively monitor patients in both outpatient and surgical settings.

Recurrent post-tympanostomy tube otorrhea secondary to aerobic endospore-forming bacilli: a case report and brief literature review.

We report a unique case in which a 57-year-old man with an 8-year history of late recurrent post-tympanostomy tube otorrhea (PTTO) was found to harbor Bacillus subtilis, an aerobic endospore-forming bacillus that is typically resistant to chemical and physical agents because of its unique life cycle. Removal of the patient's tympanostomy tube resulted in complete resolution of his long-standing otorrhea. We also review the etiologies of and treatment strategies for early, late, chronic, and recurrent PTTO. We conclude that regardless of the etiology, a patient with persistent or recurrent PTTO should consider undergoing removal of the ventilation tube.

Improved facial nerve outcomes using an evolving treatment method for large acoustic neuromas.

OBJECTIVE: To describe a successful paradigm for the treatment of large acoustic neuromas (vestibular schwannomas). STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: The charts of 2,875 acoustic neuroma patients at Michigan Ear Institute were reviewed to identify 153 patients who underwent surgical resection for large acoustic neuromas (>=3 cm) between 2000 and 2009. INTERVENTION(S): Staged surgical resection or single stage surgery with or without adjuvant stereotactic radiosurgery. MAIN OUTCOME MEASURE(S): Postoperative facial nerve outcomes are reported using the House-Brackmann (HB) facial nerve grading scale and compared with historical controls from a literature review. Rates of adverse outcomes are also reported. RESULTS: Seventy-five patients underwent staged surgical resection of their tumors, whereas 78 patients underwent either single stage surgery or surgery with subsequent stereotactic radiosurgery. Eighty-one percent of patients in the staged surgical resection group had a postoperative HB Grade I or II facial nerve function compared with 75% in the single stage surgical group. Overall, 78% of patients in the current study had HB Grade I or II after treatment compared with a mean of 53% in the literature for similar sized tumors. Our methods including the decision to use staged surgery when necessary, dissection of tumor with stimulating dissector-directed intraoperative monitoring, and use of adjuvant stereotactic radiosurgery are described. CONCLUSION: Using the described paradigm, large acoustic neuromas can be successfully treated with either staged or single-stage surgical resection with or without adjuvant radiosurgery to obtain more favorable facial nerve outcomes than historically reported controls while minimizing morbidity for the patient.

Temporal bone osteoradionecrosis after surgery and radiotherapy for malignant parotid tumors.

OBJECTIVE: To assess the incidence of osteoradionecrosis (ORN) of the temporal bone after surgery with radiotherapy for malignant parotid tumors. SETTING: A tertiary care, academic medical center. PATIENTS: All patients who underwent surgical resection with postoperative radiotherapy (RT) for a malignant parotid tumor between July 1988 and July 2007. INTERVENTIONS: A retrospective chart analysis to determine the extent of surgery, the RT parameters, and the incidence of ORN of the temporal bone. MAIN OUTCOME MEASURES: The incidence of ORN in 3 subgroups of patients. RESULTS: The 221 patients with malignant parotid tumors who underwent surgical resection with postoperative RT were divided into groups 1, parotidectomy only; 2, parotidectomy with mastoidectomy; and 3, parotidectomy with subtotal petrosectomy. The overall incidence of temporal bone ORN in group 1 was 2 (2%) of 106; in group 2, 8 (13%) of 64; and in group 3, 0 (0%) of 51. CONCLUSION: The incidence of temporal bone ORN is higher after mastoidectomy for facial nerve identification or resection in patients undergoing parotidectomy with postoperative radiotherapy. Oversew of the ear canal with mastoid obliteration should be considered in this subgroup of patients to avoid this long-term complication of radiotherapy used in the treatment of malignant parotid tumors.

Association between adipose graft usage and postoperative headache after retrosigmoid craniotomy.

OBJECTIVE: To evaluate the association between extradural abdominal fat graft placement for the closure of retrosigmoid craniotomy defects and postoperative headache. STUDY DESIGN: Retrospective chart review and analysis of patient questionnaires. SETTING: Tertiary care academic medical center. PATIENTS: One hundred twenty-seven patients who underwent retrosigmoid craniotomy between March 1999 and December 2006. INTERVENTION(S): All patients underwent retrosigmoid craniotomy for removal of cerebellopontine angle tumors and received either an abdominal fat graft closure or a standard wound closure. MAIN OUTCOME MEASURE(S): Using a written patient questionnaire, the presence or absence of both overall postoperative headache and specific postcraniotomy headache according to International Headache Society criteria was assessed. Of those patients who had postoperative headaches, the evaluation of headache severity was assessed using a standardized 5-point scale. RESULTS: Eighty-five patients returned completed questionnaires. Fifty-two respondents received adipose grafts; 33 did not. The adipose group demonstrated significantly less chronic postcraniotomy headaches (11.9% versus 30.3%; p < 0.05). Additionally, the adipose group described less severe headaches at all time frames studied with significant differences at 1 month (1.59 versus 2.29; p < 0.05) and 3 months (1.37 versus 2.06; p < 0.05) using the modified headache severity scale. CONCLUSION: When compared with standard wound closure without adipose grafting, use of an abdominal fat graft during retrosigmoid craniotomy wound closure is associated with both decreased incidence of chronic postoperative headache and decreased severity of postoperative headaches at all time intervals studied.

Effects of electrical stimulation and gonadal steroids on rat facial nerve regenerative properties.

PURPOSE: The neurotherapeutic effects of nerve electrical stimulation and gonadal steroids have independently been demonstrated. The purpose of this study was to investigate the therapeutic potential of a combinatorial treatment strategy of electrical stimulation and gonadal steroids on peripheral nerve regeneration. METHODS: Following a facial nerve crush axotomy in gonadectomized adult male rats, testosterone propionate (TP), dihydrotestosterone (DHT), or estradiol (E(2)) was systemically administered with/without daily electrical stimulation of the proximal nerve stump. Facial nerve outgrowth was assessed at 4 and 7 days post-axotomy using radioactive labeling. RESULTS: Administration of electrical stimulation alone reduced the estimated delay in sprout formation but failed to accelerate the overall regeneration rate. Conversely, TP treatment alone accelerated the regeneration rate by approximately 10% but had no effect on the sprouting delay. Combining TP with electrical stimulation, however, maintained the enhanced rate and reduced the sprouting delay. DHT treatment alone failed to alter the regeneration rate but combining it with electrical stimulation increased the rate by 10%. E(2) treatment alone increased the regeneration rate by approximately 5% but with electrical stimulation, there was no additional effect. CONCLUSIONS: Electrical stimulation and gonadal steroids differentially enhanced regenerative properties. TP, an aromatizable androgen, augmented regeneration most, suggesting a synergism between androgenic and estrogenic effects. Therapeutically, combining electrical stimulation with gonadal steroids may boost regenerative properties more than the use of either treatment alone.