Samuel A. C. MacKeith

Pre-operative imaging for cochlear implantation: magnetic resonance imaging, computed tomography, or both?

Abstract Objective Previous studies of computed tomography (CT) and magnetic resonance imaging (MRI) before cochlear implantation have been of limited sample size, lacked statistical analysis, and been inconsistent in their conclusions. We aim to quantify the utility of CT, MRI, and their combination in order to rationalize their selection. Methods Clinical records and radiological findings were correlated retrospectively in 158 adults and children. All underwent both CT and MRI. Results A total of 27.9% (95% confidence interval (CI): 21.0–35.5) of patients had a significant radiological abnormality, but these were considered critical to subsequent management in only 12.7% (7.9–18.9). All these were detected by MRI. They were missed by CT in 6.3% (3.1–11.3). In all, 6.3% also had non-critical abnormalities that were reported only on CT. Cochlear dysmorphisms were more common in children but the overall frequency of abnormalities and their detection rates did not depend on age. Omitting CT and using MRI alone are estimated to miss no critical abnormalities (95% CI: 0–2.3 %). Conclusions While CT may be better at defining some abnormalities, MRI appears to be able to detect all abnormalities that are critical to patient management. Most candidates for cochlear implantation can therefore be assessed by MRI initially. CT is most likely to be helpful in those with a history of severe middle ear disease, meningitis, or dysmorphic syndromes, who should undergo both CT and MRI.

Simultaneous Labyrinthectomy With Cochlear Implantation in Patients With Bilateral Ménière’s Disease:

Objective: The development of second-side Ménière’s disease in the only remaining serviceable ear is difficult to treat. We describe an intervention to control disabling disease combining a labyrinthectomy and cochlear implant to restore hearing. Methods: Following a thorough preoperative assessment and consenting process, 2 patients underwent labyrinthectomy of the affected ear with simultaneous cochlear implantation. Results: Both patients achieved control of Ménière’s attacks with improved hearing rehabilitation. Oscillopsia was noted by both patients. Both patients were pleased to have undergone the treatment. Conclusion: Severe symptomatic second-side Ménière’s disease in the only hearing ear is uncommon. We report the successful treatment of 2 patients in this difficult management scenario, by simultaneous surgical labyrinthectomy and cochlear implantation. We propose this as a potential management strategy in this rare but complex group of patients in whom all less destructive measures have failed.

Trends In Acoustic Neuroma Management: A 20-Year Review of the Oxford Skull Base Clinic

Objective To describe the change in the management of acoustic neuromas at one United Kingdom center over a 20-year period and to compare this with what is known regarding trends in practice on a national and international scale. Design, Setting, and Participants Data was collected prospectively on all patients attending the Oxford Skull Base Clinic between 1990 and 2009. Main Outcome Measures The proportion of patients managed initially by observation versus radiotherapy versus surgery was recorded for each year. Results Significantly more patients received radiation treatment (instead of surgery) between 2000 and 2009 when compared with 1990 to 1999. Compared with national audit data, the Oxford Skull Base Clinic treats a higher proportion of patients with radiotherapy and significantly lower proportion with surgery, though the trend nationally is toward more observation and radiotherapy and less surgery. Conclusion Surgery will remain crucial in the management of some patients with acoustic neuromas (usually those with the larger tumors where radiosurgery is recognized to be less appropriate), but using current trends to predict future practice would suggest that alternative nonmicrosurgical treatment may play an increasingly important role in the future.

Middle ear gentamicin-soaked pledgets in the treatment of Ménière's disease.

Objective Assess the relative efficacy and results of the round window hyaluronic acid pledget depot method for intratympanic gentamicin delivery in Ménière’s disease. Study Design Retrospective case review. Setting Tertiary referral hospital. Patients Prospective symptomatic and audiologic data were collected on 28 patients undergoing intratympanic gentamicin therapy for Ménière’s disease refractory to medical treatment between 2003 and 2009. Intervention All patients had the round window membrane exposed via a tympanomeatal flap, and any adhesions were removed. Hyaluronic acid pledgets soaked in 40 mg/ml of gentamicin were then packed into the round window niche and posterior mesotympanum, and the tympanomeatal flap was replaced. Main Outcome Measures Patients audiologic and vertigo symptom outcome scores were recorded at follow-up according to the AAO-HNS 1995 guidelines for reporting results in Ménière’s disease. Results Complete or substantial improvement in vertigo (class A or B) was achieved in 88.5% (23/26) of patients. Hearing loss, defined as greater than 10 dB (PTA average at 0.5, 1, 2, and 4 kHz) was noted in 12 (50%) of 24 patients including 4 patients who had developed “dead ears” (16%). The average hearing loss for all patients excluding the 4 patients with dead ears was 10.7 dB. Conclusion Round window hyaluronic acid pledget technique used as a sustained delivery vehicle for intratympanic gentamicin treatment for Ménière’s disease produces similar rates ofvertigo control compared with other techniques but a greater risk of hearing loss. We would recommend the intratympanicinjection titration technique as first line for most patients.

Recurrent aseptic meningitis as a rare but important presentation of congenital petrous apex cholesteatoma: the value of appropriate imaging

We describe the presentation, investigation and challenging management of a young adult with recurrent aseptic meningitis. The presence of cholesterol and triglycerides in the cerebrospinal fluid sample was recognised as a potential sign of an underlying dermoid or epidermoid cyst. We demonstrate how appropriate imaging of the skull base with diffusion-weighted imaging (DWI) MRI can help differentiate between lesions of the petrous apex, facilitating the diagnosis of a petrous apex congenital cholesteatoma/epidermoid cyst. Awareness of this unusual mode of presentation of a rare disease, as well as knowledge of key diagnostic investigations, may allow for earlier identification, treatment and reduced morbidity/mortality.

Balloon dilatation of tracheostomal stenosis with cuffed tracheostomy tube. A novel approach to tracheostomal dilatation.

Postlaryngectomy tracheostomal stenosis is a common complication. Stomal narrowing can be severe, requiring urgent management with dilatation of the stoma. There are numerous ways to achieve this, ranging from forcibly inserting a larger tracheostomy tube, using a graduated dilator, to surgical intervention in the form of a stomaplasty. We describe an alternative technique using a readily available cuffed tracheostomy tube. Laryngoscope, 2011

Aspirin does not prevent growth of vestibular schwannomas: A case-control study: Aspirin for Vestibular Schwannomas

To determine if aspirin intake is associated with reduced growth of vestibular schwannomas (VS). To determine the prevalence of contraindications to regular aspirin in patients with VS.

Collateral Tissue Destruction with the Harmonic Scalpel vs the Coblator Wand: How Does This Affect Tumor Resection Margins?

Objective: Oncological surgical technological innovation has produced alternative hemostatic dissection techniques. Collateral tissue destruction and impact upon assessment of tumor resection margins from Harmonic and Coblation dissectors remains unknown. This study uses an ex-vivo animal model to quantify the collateral tissue destruction caused by the harmonic scalpel vs coblator wand dissection. Method: Incisions through cow tongue were made between defined parallel lines with each dissection technique. The residual tissue width was measured with vernier calipers and subtracted from the width of original tissue. A scalpel blade was used as a control. Results: The mean width of collateral tissue destruction for each modality was as follows: harmonic cutting 3.0 mm, harmonic coagulating 4.1 mm, coblation cutting 3.5 mm, harmonic cutting under tissue tension 1.2 mm. Conclusion: This study demonstrates that tissue destruction produced when using the harmonic scalpel and coblation is significant when compared to cold steel dissection. The findings of this study should be borne in mind when using the harmonic scalpel and coblation in oncological surgery and making decisions regarding postoperative adjuvant therapy.