The 3-Dimensional Temporal Bone Dissection Manual: Operable Stepwise Models for Teaching Otologic Surgery

Deconstructing surgeries into steps and providing instructions with illustrations has been the staple of surgical textbooks for decades. However, it may be difficult for the novice surgeon to interpret 2-dimensional (2D) illustrations into 3D surgeries. The objective of this study is to create operable models that demonstrate the progression of surgery in 3D and allow for mastering the final steps of the operation first. Mastoidectomy was performed in a stepwise fashion to different end points on 5 identical 3D-printed temporal bone models to represent 5 major steps of the operation. The drilled models were computed tomography scanned and the subsequent images were used to create 3D model copies of each step. This is the first study to demonstrate that it is possible to create, scan, and copy stepwise, operable, patient-specific 3D-printed models, which the trainee can both reference as a 3D dissection guide and can operate on repeatedly and in any order.

Socioeconomic Status and Cochlear Implant Usage: A Datalogging Study

OBJECTIVE

To evaluate the associations between proxy measures of socioeconomic status (SES) and usage of cochlear implants.

STUDY DESIGN

Retrospective case series.

METHODS

Usage outcomes were measured among patients with a cochlear implant and data logging at a tertiary care children's hospital between 2002 and 2017. Time per day with cochlear implant turned on, coil off, and listening to speech in noise and speech in quiet were extracted from audiology records, averaging right and left ear usage for those with bilateral implants. Associations between cochlear implant usage and demographic factors such as insurance type and median household income for zip code were assessed.

RESULTS

There were 142 total patients; 74 had bilateral usage data. Mean on air time was 10.76 hours (SD: 4.4). Those with private insurance had 1.2 hour more on air time/day (P = .047) and 0.9 hour more quiet time/day (P = .011) compared to those with public insurance. Younger age at last visit was associated with increased speech in quiet (B = -.08; 95% CI: -0.12-[-0.05], P < .001) and coil off (B = -0.06; 95% CI: -0.11-[-0.02], P = .006). Younger age at implant was associated with longer duration since last data logging visit (B = -10.46; 95% CI: -18.41-[-2.51], P = .010), more daily use (on air; B = -0.23; 95% CI: -0.43-[-0.03], P = .026), and increased time spent listening to speech in noise (B = -0.07; 95% CI: -0.14-[-0.01], P = .024). No other significant associations between datalogging output and each proxy SES factor were found.

CONCLUSIONS

Lack of private insurance and older age at implantation decreased access to binaural hearing for children and young adults with cochlear implants.

Cochlear Implant Salvage in Case of Grounding Wire Extrusion

OBJECTIVES

Cochlear implantation (CI) is a safe and effective procedure for hearing rehabilitation, with few major complications. Device exposure or extrusion is a rare but major complication that often necessitates explantation due to wound dehiscence or infection. The objective of this report is to present a previously undescribed case in which the cochlear implant grounding wire extruded in 16-month-old patient 3 months post-operatively in the absence of trauma or infection.

METHODS

We reviewed the case report and the pertinent literature.

RESULTS

A 16-month old male suffered extrusion of his left cochlear implant grounding wire without known etiology 86 days post-operatively after bilateral cochlear implantation. The patient was taken for surgery, and the electrode was reimplanted without complication followed by 48 hours of prophylactic intravenous antibiotics. Nine month follow up revealed the implant functioning appropriately, with no further major complications encountered.

CONCLUSION

We present this unique case to demonstrate that a cochlear implant grounding wire extrusion is not necessarily an indication for explantation in the absence of infection.

Cortactin Phosphorylation by Casein Kinase 2 Regulates Actin-Related Protein 2/3 Complex Activity, Invadopodia Function, and Tumor Cell Invasion

Malregulation of the actin cytoskeleton enhances tumor cell motility and invasion. The actin-binding protein cortactin facilitates branched actin network formation through activation of the actin-related protein (Arp) 2/3 complex. Increased cortactin expression due to gene amplification is observed in head and neck squamous cell carcinoma (HNSCC) and other cancers, corresponding with elevated tumor progression and poor patient outcome. Arp2/3 complex activation is responsible for driving increased migration and extracellular matrix (ECM) degradation by governing invadopodia formation and activity. Although cortactin-mediated activation of Arp2/3 complex and invadopodia regulation has been well established, signaling pathways responsible for governing cortactin binding to Arp2/3 are unknown and potentially present a new avenue for anti-invasive therapeutic targeting. Here we identify casein kinase (CK) 2α phosphorylation of cortactin as a negative regulator of Arp2/3 binding. CK2α directly phosphorylates cortactin at a conserved threonine (T24) adjacent to the canonical Arp2/3 binding motif. Phosphorylation of cortactin T24 by CK2α impairs the ability of cortactin to bind Arp2/3 and activate actin nucleation. Decreased invadopodia activity is observed in HNSCC cells with expression of CK2α phosphorylation-null cortactin mutants, shRNA-mediated CK2α knockdown, and with the CK2α inhibitor Silmitasertib. Silmitasertib inhibits HNSCC collective invasion in tumor spheroids and orthotopic tongue tumors in mice. Collectively these data suggest that CK2α-mediated cortactin phosphorylation at T24 is critical in regulating cortactin binding to Arp2/3 complex and pro-invasive activity, identifying a potential targetable mechanism for impairing HNSCC invasion. IMPLICATIONS: This study identifies a new signaling pathway that contributes to enhancing cancer cell invasion.Visual Overview: http://mcr.aacrjournals.org/content/molcanres/17/4/987/F1.large.jpg.

Solitary fibrous tumor of the infratemporal fossa

Solitary fibrous tumors represent fewer than 2% of all soft tissue tumors, and only about 12-15% of them occur in the head and neck. We report a case of a 38-year-old male who presented with a six-month history of increasing right cheek swelling. Computed tomography of the paranasal sinuses with contrast demonstrated a well-circumscribed avidly enhancing mass in the right retroantral fat. On magnetic resonance imaging the lesion was homogenously slightly hyperintense to muscle on T1 weighted and T2 weighted images and enhanced avidly with contrast. Surgical resection was performed and pathology was consistent with solitary fibrous tumor. There have been very few reported cases of solitary fibrous tumors in the infratemporal fossa and none described as originating in the retroantral fat.

Prophylactic valacyclovir in a patient with recurrent vestibular disturbances secondary to vestibular neuritis

A 57-year-old woman with herpes labialis and previously diagnosed with vestibular neuritis experienced recurrences of vertigo and disequilibrium. Initially preceded by oral herpes outbreaks or upper respiratory infections, these recurrences became spontaneous and more frequent. Vestibular function demonstrated a 25% decrease in energy function in the right and the patient had left beating nystagmus on positional maneuver. Her reoccurrences of vestibular disturbances were followed up. Concurrently, she was prescribed daily valacyclovir (500 mg, 1 per day) given for the prevention of herpes labialis outbreaks by her primary care physician. Recurrences of disequilibrium stopped completely as well as oral herpes outbreaks.