Minimally Invasive Repair of Tegmen Defects Through Keyhole Middle Fossa Approach to Reduce Hospitalization.

OBJECTIVE: The middle fossa craniotomy for tegmen defect repair provides wide access. This approach often requires temporal lobe manipulation, lumbar drain placement, and longer recovery. We describe a keyhole middle fossa approach with a simple titanium skull base repair that allows for wide access with no temporal lobe manipulation and does not require lumbar drain placement, which results in a dramatic reduction in hospital length of stay. METHODS: A retrospective review was performed on 14 consecutive patients with spontaneous cerebrospinal fluid (CSF) otorrhea. Each patient underwent a keyhole middle fossa approach followed by multilayer dural repair with titanium mesh "gull wing" skull base reconstruction. Postoperative measures included operative time, length of hospital stay, CSF leak recurrence, and surgical complications (seizures, hemorrhage, aphasia, infection). RESULTS: The average age of the patients was 60.7 ± 12.7 years old, and average body mass index was 32.8 ± 7.9 kg/m2. Nine of the patients were female. The average operative time was 103 ± 32.8 minutes. The average hospital length of stay was 1.4 days. There were no cases of postoperative CSF otorrhea, meningitis, aphasia, or seizures. There were no recurrences over a mean follow-up of 20.3 months (range: 5-48 months). CONCLUSIONS: A minimally invasive keyhole middle fossa approach with a multilayer dural reconstruction including titanium mesh "gull wing" skull base repair provides a quick, effective treatment for a broad spectrum of tegmen defects and meningoencephaloceles. This exposure and reconstruction technique do not require the use of a lumbar drain and result in minimal hospitalization.

Combined Open and Endoscopic Endonasal Skull Base Resection of a Rare Endometrial Carcinoma Metastasis.

In the absence of significant extracranial disease, patients with solitary brain metastases have shown benefit with resection. Brain lesions due to endometrial cancer are uncommon, and the only described skull base involvement is limited to the pituitary gland. We report the case of a 60-year-old female with endometrial cancer who presented with weeks of right cheek pain and numbness that was accompanied by headaches. We describe the magnetic resonance imaging (MRI) findings and surgical resection of a solitary endometrial metastasis involving the infratemporal fossa, middle fossa, cavernous sinus, trigeminal nerve, and nasal sinuses. Due to extensive nasal and lateral involvement, a combined open and endoscopic approach was planned. The patient was discharged home without complication. She underwent adjuvant radiotherapy. Despite its suspected indolent course, intracranial endometrial adenocarcinoma metastases are gaining higher prevalence. This case report documents the first direct neural spread of an endometrial primary, and highlights the potential for extra-axial sites of metastasis.

Radiographic Assessment of the presigmoid retrolabyrinthine approach.

BACKGROUND: Lesions of the petroclival fissure are difficult to access surgically. Both retrosigmoid and presigmoid retrolabyrinthine approaches have been described to successfully treat these complex tumors. The retrosigmoid approach offers quick and familiar access, whereas the presigmoid retrolabyrinthine approach reduces the operative distance and the need for cerebellar retraction. The presigmoid retrolabyrinthine approach, however, is constrained by anatomical limits that can be subject to patient variation. We sought to characterize the surgically relevant variation to guide preoperative assessment. METHODS: One hundred and seventy-seven high-resolution computed tomography scans of the head (without preexisting pathology) were reviewed. Three hundred and fifty-four temporal bone scans were analyzed for level of aeration, size of Trautmann's triangle dura, and petrous slope. Petrous slope is the angle between the anterior sigmoid sinus and the petroclival fissure at the level of the internal acoustic canal. RESULTS: Trautmann's triangle area had a mean of 185.15 mm2 (range 71.4-426.7 mm2). Petrous slope had a mean value of 149° (range 106-178°). Increasing aeration was found to be correlated with decreasing petrous slope and decreasing Trautmann's triangle area. CONCLUSION: The presigmoid retrolabyrinthine approach is uniquely confined. Variations in temporal bone anatomy can have dramatic impacts on the operative time, risk profile, and final exposure. Preoperative assessment is critical in guiding the surgeon on the appropriateness of approach. Preoperative measurement of Trautmann's triangle, petrous slope, and aeration can help to reduce surgical morbidity.

Reduction in Temporary and Permanent Audiological Injury Through Internal Jugular Vein Compression in a Rodent Blast Injury Model.

HYPOTHESIS: Internal jugular vein (IJV) compression influences not only intracranial but also intracochlear physiology and has demonstrated preclinical effectiveness in reducing acute audiological injury in a rodent blast model. However, the long-term effects in this model are unknown. BACKGROUND: Blast wave-induced audiological injury from an improvised explosive device is a leading cause of morbidity among service members in theater but there are limitations to the current protective measures. METHODS: For this study, we exposed 20 Sprague Dawley rats to a 16.8 ±â€Š0.3 PSI (195.3 dB SPL) right-sided shock wave in which 10 had application of a custom IJV compression collar in place at the time of injury. RESULTS: IJV compression at the time of injury was shown acutely to significantly reduce the incidence of tympanic membrane rupture and the initial temporary threshold shift on otoacoustic emissions in both the right and left ears of animals who had collar application immediately after and 7 days post injury. At 28 days from injury, collared animals demonstrated a return to baseline of otoacoustic emission values while the noncollared animals had persistent threshold shifts, signifying the presence of a permanent threshold shift only in those animals without collar application. IJV compression was also found to significantly reduce hair cell loss at the base of the cochlea secondary to mechanical trauma from the blast wind. CONCLUSION: Previously observed acute protective effects of IJV compression are sustained at chronic time points. IJV compression can potentially be used to reduce long-term permanent morbidity from blast-induced audiological trauma.

Internal Jugular Vein Compression: A Novel Approach to Mitigate Blast Induced Hearing Injury.

HYPOTHESIS: Internal jugular vein (IJV) compression before blast injury will lead to reduced risk of traumatic hearing injury following exposure to a blast injury. BACKGROUND: IJV compression and its effects on not only intracranial, but also intracochlear pressure may potentiate blast induced hearing injury, therefore, precluding its use as a prophylactic therapy for blast induced traumatic brain injury. METHODS: Twenty Sprague Dawley rats were exposed to a 17.9 ±â€Š0.4 PSI (195.8 dB SPL) right sided shock wave in which 10 had application of a custom IJV compression collar before injury. All rodents received baseline and post blast injury otoacoustic emission (OAE) and auditory brainstem response (ABR) testing followed by cochlear histology. RESULTS: IJV compression was shown to significantly reduce ABR and OAE threshold shifts in comparison to the non-intervention group by: 14.9 ±â€Š4.8 dB (right ear ABR 0.5 kHz Day 1 post blast, p = 0.01), 13.1 ±â€Š4.9 dB (right ear ABR 4 kHz Day 1 post blast, p = 0.04), 16.5 ±â€Š4.5 dB (right ear ABR click Day 1 post blast, p = 0.003), 12.1 ±â€Š4.6 dB (right ear ABR click Day 6 post blast, p = 0.04), and 14.0 ±â€Š3.2 dB (both ears OAE 3.2-10 kHz, p < 0.0001). Also, those animals with collar application had a greater number of total hair cells per mm from 70 to 100% distance from the cochlear apex following blast injury in comparison to those without intervention (blast: 211.8 ±â€Š27.5 versus blast+collar: 355.5 ±â€Š39.5 [p = 0.0002]). CONCLUSION: This study supports the use of IJV compression in a pre-clinical model as a new prophylactic mechanism to combat blast induced hearing injury.

Congenital Cholesteatoma.

Congenital cholesteatoma is one of the more common causes of the onset of childhood conductive hearing loss unrelated to middle ear effusion. If undiagnosed, the disease can progress to irreversibly destroy the conductive hearing architecture, as well as the surrounding skull base of the lateral temporal bone. When diagnosed early, the growth can be removed and the conductive hearing mechanism preserved in the vast majority of patients. Because most children are asymptomatic, the burden falls on primary care providers to perform pneumatic otoscopy and visualize all quadrants of the tympanic membrane even in young children who frequently resist attempts to conduct a thorough examination to rule out suspicious lesions. [Pediatr Ann. 2016;45(5):e167-e170.].

Implantable hearing devices.

PURPOSE OF REVIEW: Implantable hearing devices have been developed to address the shortcomings of traditional hearing aids. Currently, there are two US Food and Drug Administration clinical trials evaluating fully implantable hearing devices. RECENT FINDINGS: Implantable hearing devices attempt to improve upon stigma, cosmesis, occlusion effect, and feedback, as well as other factors that prevent patients from using traditional hearing aids. However, there are many challenges inherent in designing an implantable hearing device. Different devices have attempted to overcome these challenges in different ways. We will discuss these differences in design, their individual pros and cons as well as directions of future research. SUMMARY: Although implantable hearing devices are not currently available they do hold promise for patients not adequately served by conventional hearing aids.

Secreting jugulotympanic paraganglioma with venous involvement into the thorax.

Paragangliomas are highly vascular tumors that arise from chief cells in extra-adrenal paraganglia of the autonomic nervous system. Jugulotympanic paragangliomas involve the middle ear and jugular fossa. Secreting jugulotympanic paragangliomas with thoracic extension are rare. We report a case with unexpected involvement of the internal jugular vein. Otolaryngologists should be aware that the jugulotympanic paragangliomas traverse variable anatomic pathways. Multiple imaging options, including magnetic resonance venography, are useful and should include the neck for definitive characterization of tumor anatomy. Patients with refractory hypertension and masses suspicious for paraganglioma should be examined for functional tumors.

Effect of recurrent laryngeal nerve section on the laryngeal muscles of adult rabbits.

OBJECTIVE: To examine the effect of recurrent laryngeal nerve section on myonuclear addition and myofiber remodeling in adult rabbit laryngeal muscles. STUDY DESIGN AND SETTING: Unilateral section of the recurrent laryngeal nerve was performed on adult rabbits. Rabbits were labeled with bromodeoxyuridine, euthanized, and the laryngeal muscles were examined for bromodeoxyuridine (brdU) and neonatal myosin heavy chain (MyHC) expression. RESULTS: One week after nerve section, brdU-positive myonuclei were significantly increased on the denervated and contralateral sides. Neonatal MyHC expression significantly increased. By 24 weeks, the upregulation of myonuclear addition returned to control levels. CONCLUSION: Laryngeal muscle denervation results in significant upregulation of myonuclear addition. Denervation also resulted in a significant upregulation of neonatal MyHC expression. SIGNIFICANCE: Laryngeal muscles can be successfully reinnervated after long periods of denervation. This significant and maintained increase in myonuclear addition may contribute to the ability of laryngeal muscles to survive for extended periods following interruption of the recurrent laryngeal nerve.

Obstructing tracheobronchial schwannoma.

Endotracheal and endobronchial schwannomas are extremely rare tumors of neurogenic origin. These tumors often present late. Common symptoms of hemoptysis and dyspnea result from the size and location of the tumors. Two cases of tracheobronchial schwannoma with proximal airway obstruction are reported. Various diagnostic modalities employed in the evaluation of these tumors are reviewed. Because malignant transformation is exceedingly rare, operative resection of tracheobronchial schwannomas based on the principle of conservation of lung parenchyma is emphasized.

Age-related olfactory dysfunction: cellular and molecular characterization in the rat.

BACKGROUND: Olfactory receptor neurons (ORNs) undergo apoptosis at a baseline rate even in the absence of obvious disease. Although the precise triggers of the apoptotic cascade are unclear, ORNs are exposed directly to the external environment, making them susceptible to injury. As an adaptive mechanism, mammals have the ability to replace lost ORNs throughout adult life from neuronal precursors within the olfactory epithelium (OE). In humans, this process fails with age as the surface area of the OE and the number of ORNs decline, coupled with a loss of clinical olfactory function. The question addressed in this study is whether this age-related failure of olfactory sensation is a result of a decrease in neuronal proliferation or an increase in ORN cell death. METHODS: To begin to address this question the ribonuclease protection assay was used to assess expression of apoptosis-related genes in rat OE as a function of age. Second, the terminal deoxynucleotide transferase end labeling assay was used to assess the percentage of ORNs undergoing apoptosis (apoptotic index) in three groups of animals: young (12 weeks), old (32 months), and bulbectomized rats. Bulbectomy is a standard model for ORN injury associated with a massive increase in ORN apoptosis and serves as a positive control. RESULTS: Ribonuclease protection assay data indicate an age-related increase in Bax, Bcl-xL, and procaspase-3 messenger RNA expression in aged compared with young rats. A similar but more pronounced increase in expression of these apoptotic-related genes is seen after bulbectomy. The terminal deoxynucleotide transferase end labeling assay also showed a statistically significant increase in the apoptotic index with both age and bulbectomy. CONCLUSION: Taken together, the current results indicate that aging and injury induce parallel changes in OE. Furthermore, these findings support the hypothesis that age-related olfactory dysfunction is, at least in part, related to an increase in ORN cell death.