Faculty Bibliography

OBJECTIVES/OBJECTIVE:Congenital anterior skull base defects with meningoencephaloceles causing nasal obstruction are rare clinical entities. Nasal obstruction in children may also be a symptom of multiple benign nasal and allergic disorders, making the initial diagnosis of meningoencephalocele difficult. Traditionally, skull base defects have been repaired via a bifrontal craniotomy approach. With the advent of pediatric endoscopic instrumentation, more of these lesions are accessible via an intranasal endoscopic approach, even in the infant population. However, owing to the rarity of these lesions, there is a paucity of data demonstrating successful adaptation of endoscopic skull base techniques to the pediatric population. METHODS:Retrospective review of two cases of endoscopic repair of anterior skull base defects with meningoencephaloceles at a tertiary care medical center. RESULTS:Two children, ages 15 months and 6 years, underwent successful endoscopic closure of their anterior skull base defects and resection of their intranasal meningoencephalocele with resolution of their nasal obstruction and cerebrospinal fluid rhinorrhea. CONCLUSIONS:Pediatric nasal meningoencephaloceles with anterior skull base defects can be successfully repaired via a transnasal endoscopic technique, thus minimizing the complications associated with craniotomy and frontal lobe retraction. Triplanar computed tomographic and magnetic resonance imaging is paramount to evaluate the caliber of the skull base defect, consistency of the herniated intracranial contents, as well as the presence of cerebral vasculature.

BACKGROUND AND OBJECTIVE: Patients who require surgery for chronic otitis media with perforation and cholesteatoma frequently provide no residual tympanic membrane that is usable in grafting procedures. A novel technique of total tympanic membrane reconstruction (TTMR) is described that maximizes perforation closure rate in these situations while minimizing mucosalization, incomplete healing, and anterior blunting. The specific aim of this report is to assess the safety and efficacy of TTMR and to compare the results obtained with AlloDerm compared with temporalis fascia as a grafting material. METHODS: The records of 50 patients operated within the years 1999 and the 2004 were reviewed. TTMR with intact canal wall was performed in all cases. Both clinical and audiometric data were analyzed. RESULTS: Overall perforation closure rate was 92%. There was no statistical significance in closure rate when grafting with AlloDerm versus temporalis fascia. A statistically significant shortened healing time was observed with AlloDerm grafting. CONCLUSIONS: TTMR is a highly effective and safe technique

BACKGROUND: Anatomic and mucosal obstruction of the frontal sinus outflow tract (FSOT) can result in frontal sinusitis often associated with frontal headache. Thorough evaluation of symptomatic patients requires axial and coronal computerized tomographic (CT) scans of the paranasal sinuses (PNS). With the advent of multichannel multidetector CT scanning, the availability of high-quality sagittal images has become increasingly widespread. However, the utility of these images in the assessment of FSOT patency has not yet been established. METHODS: A retrospective review of coronal and sagittal images from 25 PNS CT scans (50 sides) were randomized, blinded, and independently evaluated by two neuroradiologists. FSOT obstruction by agger nasi cells, the ethmoid bulla, and mucosal disease was assessed. A degree of confidence was rendered for each of these findings. The results were then compared against a consensus diagnosis, which was rendered based upon simultaneous reading of the coronal and sagittal images. Generalized estimating equations were used to assess the difference between sagittal and coronal images in terms of reader confidence and diagnostic concordance with the consensus. RESULTS: Review of sagittal images had a higher degree of concordance with the consensus than did coronal images, and was highest for mucosal disease. Both readers were more confident in rendering a diagnosis based upon the sagittal images. CONCLUSION: Sagittal reformatted CT images of the PNS are helpful in the radiologic evaluation of the FSOT. Experienced neuroradiologists had a higher degree of confidence in the diagnosis of the obstruction of the FSOT using sagittal reformatted images

OBJECTIVES: Multichannel auditory brainstem implants (ABI) are currently indicated for patients with neurofibromatosis type II (NF2) and schwannomas involving the internal auditory canal (IAC) or cerebellopontine angle (CPA), regardless of hearing loss (HL). The implant is usually placed in the lateral recess of the fourth ventricle at the time of tumor resection to stimulate the cochlear nucleus. This study aims to review the surgical and audiologic outcomes in 18 patients implanted by our Skull Base Surgery Team from 1994 through 2003. STUDY DESIGN: A retrospective chart review of 18 patients with ABIs. METHODS: We evaluated demographic data including age at implantation, number of tumor resections before implantation, tumor size, surgical approach, and postoperative surgical complications. The ABI auditory results at 1 year were then evaluated for number of functioning electrodes and channels, hours per day of use, nonauditory side effect profile and hearing results. Audiologic data including Monosyllable, Spondee, Trochee test (MTS) Word and Stress scores, Northwestern University Children's Perception of Speech (NU-CHIPS), and auditory sensitivity are reported. RESULTS: No surgical complications caused by ABI implantation were revealed. A probe for lateral recess and cochlear nucleus localization was helpful in several patients. A range of auditory performance is reported, and two patients had no auditory perceptions. Electrode paddle migration occurred in two patients. Patient education and encouragement is very important to obtain maximum benefit. CONCLUSIONS: ABIs are safe, do not increase surgical morbidity, and allow most patients to experience improved communication as well as access to environmental sounds. Nonauditory side effects can be minimized by selecting proper stimulation patterns. The ABI continues to be an emerging field for hearing rehabilitation in patients who are deafened by NF2