Optimizing Workflow in Combined Petrosectomy Approaches: Surgical Technique and Case Series.

BACKGROUND AND OBJECTIVE: The combined petrosectomy is one of the workhorse skull base approaches to the petroclival region. Traditionally, this approach starts with a temporosuboccipital craniotomy, followed by the mastoidectomy/anterior petrosectomy, and completed with the dural opening/tumor resection. This sequence of events (neurosurgery-neuro-otology-neurosurgery) involves at least 2 handoffs and change of surgical teams and instrumentation. This report describes a resequencing of events and a modification of the technique used to craft the temporosuboccipital craniotomy, with aims to reducing handoffs between surgical teams and improving operating room workflow. METHODS: Adhering to PROCESS guidelines, a case series is provided in addition to the surgical technique and surgical images. RESULTS: The technique for performing a combined petrosectomy is described with illustrations. This description shows that the temporal bone drilling may be performed before the craniotomy to allow for direct visualization of the dura and sinuses before completing the craniotomy. In doing so, only 1 transition between the otolaryngologist and neurosurgeon is necessary, thereby improving operating room workflow and time management. A series of 10 patients is presented, showing the feasibility of this procedure and providing operative details that were previously absent in the peer-reviewed literature. CONCLUSIONS: Combined petrosectomy, although often performed in a 3-step manner with the neurosurgeon starting the craniotomy, can be performed as described here in a 2-step manner, with similar outcomes and reasonable operating time.

A Systematic Review of Closure Techniques in Lateral Skull Base Tumor Surgery.

Introduction Tumors of the lateral skull base often require collaboration between neurosurgeons and neurotologists for the surgical approach. The three main transosseous surgical approaches are retrosigmoid (RS), translabyrinthine (TL), and middle fossa (MF). The literature reflects a relative paucity regarding the various closure techniques for these approaches and the postoperative complications. We have performed a systematic review comparing closure techniques from each approach. Methods A systematic review was performed using Ovid MEDLINE (1990-2016) on closure technique and postoperative complications for patients undergoing lateral skull base surgery via the TL, RS, or MF approach. Studies were included if they contained at least 10 patients, described their closure technique, and provided data on postoperative complications. Results A total of 1,403 studies were reviewed. Of these, 53 studies met inclusion criteria yielding a total of 10,466 subjects in this analysis. The average rate of cerebrospinal fluid leak was 5.3% in the TL approach, 9% in the RS approach, and 6.2% in the MF approach. There was no significant effect of various closure techniques on postoperative wound complications in the MF approach. Multiple factors were identified which affected postoperative wound complication in the RS and TL approaches. Conclusion There are a plethora of closure techniques for lateral skull base surgery. Several techniques were identified in this review that may affect the postoperative wound complication rates in lateral skull base surgery.

Spontaneous Otorrhagia after Laparoscopic Pelvic Surgery: A Report of Two Cases.

Spontaneous otorrhagia following laparoscopic pelvic surgery is a complication that is rarely reported and incompletely understood. Few case reports have described this phenomenon, though its true incidence is unknown. It has been hypothesized that a combination of extreme patient positioning and abdominal insufflation is the contributing factor. There does not appear to be any untoward consequences and patients can be managed conservatively. We present two cases of spontaneous otorrhagia associated with laparoscopic pelvic surgery, which occurred over a 1-week period at our institution.

Pneumatization Patterns of the Petrous Apex and Lateral Sphenoid Recess.

Introduction The petrous apex poses a challenge for surgical intervention due to poor access. As intraoperative image guidance and surgical instrumentation improve, newer endoscopic approaches are increasingly favored. This study aims to provide normative data on the anatomy of the lateral sphenoid sinus recess and petrous apex. These normative data could assist in determining the efficacy of a transnasal transsphenoidal approach to lesions of the anteroinferior petrous apex. Methods This is a retrospective study investigating normative data on all maxillofacial computed tomography (CT) scans performed at a level I trauma center over a 6-month period. All appropriate images had the pneumatization pattern of the petrous apex and lateral recess of the sphenoid sinus reviewed by a single otologist and graded bilaterally. These were then analyzed in SPSS; Pearson correlation analyses and χ 2 test were used. Results A total of 481 patients were identified, yielding a total of 962 temporal bones and sphenoid sinuses for analysis. Eighty-eight percent of sides analyzed had a nonpneumatized lateral recess. The petrous apex was nonpneumatized in 54% of sides analyzed. There was a correlation noted between the degree of pneumatization of the petrous apex and pneumatization of the lateral recess of the sphenoid. Conclusion This study is the first to provide normative data comparing pneumatization of the petrous apex and sphenoid sinus. These data may support future work evaluating the utility of an endonasal approach to the petrous apex.

Denervation of the Eustachian Tube and Hearing Loss Following Trigeminal Schwannoma Resection.

Objectives To discuss eustachian tube dysfunction (ETD) as a cause of hearing loss and to discuss its pathogenesis following resection of trigeminal schwannomas. Methods Presented herein are two cases of trigeminal schwannoma that were resected surgically with sacrifice of the motor branch of the trigeminal nerve. Neither of the cases had evidence of extracranial extension nor preoperative ETD. Both patients developed ETD and have been followed without evidence of schwannoma recurrence. Conclusions Trigeminal schwannomas are rare tumors that typically require surgical resection. Hearing loss is a potential postsurgical deficit and warrants evaluation by an otolaryngologist with consideration given to a preoperative audiogram. ETD as a result of trigeminal motor branch sacrifice should be included in the differential diagnosis of postoperative hearing loss in this patient subset as it may be reversed with placement of a tympanostomy tube.

Anterior Petrosectomy: Consecutive Series of 46 Patients with Attention to Approach-Related Complications.

Objective Anterior petrosectomy(AP) was popularized in the 1980s and 1990s as micro-neurosurgery proliferated. Original reports concentrated on the anatomy of the approach and small case series. Recently, with the advent of additional endonasal approaches to the petrous apex, the morbidity of AP remains unclear. This report details approach-related morbidity around and under the temporal lobe. Methods A total of 46 consecutive patients identified from our surgical database were reviewed retrospectively. Results Of the 46 patients, 61% were women. Median age of the patients was 50 years (mean: 48 ± 2 years). Median follow-up of this cohort was 66 months. Most procedures dealt with intradural pathology (n = 40 [87%]). Approach-related morbidity consisted of only two patients (4%) with new postoperative seizures. There were only two significant postoperative hemorrhages (4%). Cerebrospinal fluid leakage occurred in two patients (4%) requiring reoperation. Conclusion Approach-related complications such as seizures and hematoma were infrequent in this series, < 4%. This report describes a contemporary group of patients treated with open AP and should serve as a comparison for approach-related morbidity of endoscopic approaches. Given the pathologies treated with this approach, the morbidity appears acceptable.

Radiographic analysis of cochlear nerve vascular compression.

OBJECTIVES: We analyzed whether radiographically demonstrated anterior inferior cerebellar artery (AICA) vascular compression of the cochleovestibular nerve in asymmetric hearing loss could be correlated to either the symptomatic ear or to cochlear nerve diameter. METHODS: We undertook a retrospective case-control study in which patients were enrolled into a database if audiometry demonstrated asymmetry of 20 dB at one frequency, asymmetry of 10 dB at two frequencies, or a difference of 20% on word recognition scores. If AICA vascular contact was demonstrated on subsequent magnetic resonance imaging of the cerebellopontine angle, patients were included in the study. Patients with vestibular schwannoma or Meniere's disease were excluded. The AICA contact was graded by a blinded neuroradiologist according to criteria proposed by McDermott et al. The cross-sectional area of the cochlear nerve was measured. RESULTS: Symptomatic ears could be correlated to a decreased cochlear nerve diameter, but not to the degree of AICA penetration into the internal auditory canal. CONCLUSIONS: AICA vascular compression of the cochleovestibular nerve does not appear to correlate to hearing loss or to cochlear nerve diameter. The finding of decreased cochlear nerve diameter in symptomatic ears implies an alternative mechanism for asymmetric hearing loss.

Mastoiditis on MRI: fact or artifact?

Fluid signal in the mastoid can be an incidental finding on T2-weighted magnetic resonance imaging and often is interpreted as mastoiditis by radiologists. This study examines 28 consecutive cases of such erroneously diagnosed "mastoiditis" and documents the presence or absence of otologic symptoms and clinical signs. We found a very low prevalence of otologic symptoms or pathology and no cases of mastoiditis in these patients, and we determined that magnetic resonance imaging is not an effective screening modality for mastoiditis. We also reviewed the literature on current diagnostic criteria for mastoiditis and propose alternative terminology to replace the use of excessively alarming terms such as "mastoiditis" unless they apply to that specific clinical diagnosis.