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Nassiri, Ashley M.

https://orcid.org/0000-0001-9665-1868

Mayo Clinic

University of Colorado Anschutz

Citations 45

Magnetic Resonance Imaging Artifact Associated With the Oticon Medical Sentio Ti Transcutaneous Bone Conduction Hearing Implant
Hennesy, Theresa B. , Zander, David , Kryzer, Theodore J., Honce, Justin M., Carlson, Matthew L., Nassiri, Ashley M. , Kryzer, Theodore, Honce, Justin M. , Carlson, Matthew L.

Otology & Neurotology | May 25, 2026 | Volume: 47 | Issue: 8 | Pages: 998-1002

10.1097/mao.0000000000004949 Get It

Objective: To evaluate magnetic resonance (MR) imaging artifact and image distortion associated with the Oticon Medical Sentio Ti bone conduction implant (BCI) and identify optimized imaging techniques. Study design: Cadaveric study. Intervention: One cadaveric head specimen was unilaterally implanted with Sentio Ti BCI according to the manufacturer's instructions. Main outcome measures: Imaging was performed with a Siemens 1.5 Tesla MR machine on XA60 software before and after implantation. Imaging was performed with both standard and metal mitigation techniques. Image scoring (diagnostic vs. nondiagnostic) and qualitative assessment of anatomic subsites were performed by 2 experienced neuroradiologists. Results: Image distortion and artifact were noted in all postimplant sequences. For all sequences, imaging of the ipsilateral middle ear, mastoid, and internal auditory canal (IAC) was nondiagnostic. The axial T1 turbo spin echo high bandwidth sequence had the best artifact reduction; however, the ipsilateral temporal bone remained nondiagnostic. Notably, nonecho planar diffusion-weighted imaging (non-EPI DWI) was nondiagnostic for both the ipsilateral temporal bone and the contralateral IAC and middle ear. Conclusions: After implantation of the Sentio Ti BCI, imaging of the ipsilateral temporal bone is rendered nondiagnostic on all MR sequences due to artifact despite the use of metal mitigation techniques. Importantly, the non-EPI DWI HASTE sequence, which is used for cholesteatoma surveillance, is nondiagnostic for all ipsilateral and most contralateral temporal bone subsites, making cholesteatoma surveillance challenging with an implant in place. This finding is critical for clinical decision-making, as rehabilitation of conductive hearing loss in the setting of chronic otitis media is among the most common indications for use of a BCI.
Proposed Development of a New Staging System for Hearing Loss: Countermeasure 2 of the Hearing Health Collaborative
Carlson, Matthew L., Zwolan, Teresa A. , Cosetti, Maura K. , Gubbels, Samuel P., Hashmi, Ardeshir Z. , Holcomb, Meredith A. , Jilla, Anna Maria, Kelley, Barbara, Lohse, Christine M. , Marinelli, John P. , McKee, Michael , Moody-Antonio, Stephanie A., Miller, Erin L. , Nassiri, Ashley M. , Reed, Nicholas S. , Spankovich, Christopher , Tieben, John, Zeitler, Daniel M. , Sydlowski, Sarah A., Tieben, John E, Carlson, Matthew L. , Bush, Matthew L. , Dunn, Camille C. , Gurgel, Richard Klaus , Hunter, Jacob B. , Jilla, Anna Marie , Moody‐Antonio, Stephanie , Miller, Erin L., Sladen, Douglas P. , Yueh, Bevan , Sydlowski, Sarah

Otology & Neurotology | December 22, 2025 | Volume: 47 | Issue: 2 | Pages: e158-e163

10.1097/mao.0000000000004700 Get It

Hearing loss is a highly prevalent disease state affecting almost 1 in 5 individuals globally. Growing research shows that untreated or undertreated hearing loss carries significant long-term sequelae, including increased risk of social isolation, depression, and cognitive decline, among other ramifications. Limited awareness and common misperceptions among the general US adult population and primary care providers contribute to low rates of referral to hearing specialty clinics and underutilization of hearing aids, cochlear implants, and other rehabilitative devices. Comprised of diverse membership, the Hearing Health Collaborative (HHC) was formed in May 2021 to identify and overcome challenges impacting good health care practices and public policy on hearing care in connection with healthy aging. This editorial documents a recent outcome of the HHC derived from a structured A3 process. Specifically, initiative 2, a proposal to develop a simple, clinically anchored staging system primarily for use by frontline providers and patients, is presented. Unlike other common disorders that harbor long-term health sequelae, a corresponding pragmatic clinical staging system—leveraging precedent disease staging convention, based on clinically meaningful outcomes and prognosis for acquired hearing loss—does not exist. The development of this staging system will potentially allow for improved communication across providers and patients, facilitate referral pathways, and ultimately enable patient access to timely and appropriate care.
Highly Coordinated Cochlear Implant Care With Remote Programming: Clinical, Financial, and Implementation Outcomes for the Complete Cochlear Implant Care (CCIC) Model
Nassiri, Ashley M. , Saoji, Aniket A. , DeJong, Melissa D., Tombers, Nicole M. , Lohse, Christine M. , Driscoll, Colin L. W., Neff, Brian A., Haynes, David S. , Daher, Ghazal S. , Carlson, Matthew L., Moriarty, James P. , Borah, Bijan J. , Carlson, Matthew L.

Otology & Neurotology | November 14, 2025 | Volume: 47 | Issue: 2 | Pages: e201-e207

10.1097/mao.0000000000004720 Get It

Objective: The Complete Cochlear Implant Care (CCIC) model is a highly coordinated care delivery model reducing and condensing in-person visits for cochlear implant (CI) patients, leveraging telehealth and remote programming. Clinical, quality-of-life, implementation, patient experience, and financial outcomes of the clinical trial are reported. Study design: Prospective, nonrandomized, 2-arm clinical trial Setting: Tertiary referral CI center Patients: Adult CI candidates Interventions: Cochlear implantation Main outcome measures: Speech perception, quality of life, implementation, patient experience, and financial outcomes for both CCIC and traditional care delivery models. Results: Patients participating in the traditional and CCIC delivery models demonstrated 12-month postoperative speech perception scores comparable to nationally reported outcomes (CNC 61% and 72% and AzBio in quiet 75% and 87% for traditional and CCIC cohorts, respectively). Quality-of-life evaluation using the CIQOL-10 demonstrated similar 12-month postoperative scores between groups (52 and 54 for traditional and CCIC cohorts, respectively). The CI Patient Experience Survey demonstrated high satisfaction outcomes in ease of communication, preparedness for surgery, and overall care in both cohorts. Implementation analysis of the CCIC model revealed perceived benefits from staff and clinicians; however, support for expansion of the program was contingent upon the availability of app-based or web-based remote programming technology. Finally, financial analysis revealed decreased out-of-pocket costs for CCIC patients. Conclusion: The CCIC model has the potential to dramatically streamline hearing health care delivery and reduce out-of-pocket costs for CI recipients. Clinical outcomes between cohorts were comparable in this feasibility study; however, a sufficiently powered trial is required to definitively comment on clinical outcomes with the new care delivery model.
Rationale for the Development of a Universal Hearing Metric for Public Consumption: Initiative 1 of the Hearing Health Collaborative
Reed, Nicholas S. , Assi, Sahar , Carlson, Matthew L. , Cosetti, Maura K. , Gubbels, Samuel P., Holcomb, Meredith A. , Jilla, Anna Marie , Lin, Frank R., Marinelli, John P. , Myers, Clarice, Sladen, Douglas P. , Spankovich, Christopher , Sydlowski, Sarah, Nassiri, Ashley M. , Nassiri, Ashley M , Bush, Matthew L. , Creel, Liza M , Gurgel, Richard Klaus , Lin, Frank R. , Yueh, Bevan

Otology & Neurotology | May 13, 2025 | Volume: 46 | Issue: 7 | Pages: 743-747

10.1097/mao.0000000000004523 Get It

Objective Present the rationale for the development of a new, patient-facing vital sign for adult hearing. Study Design Structured A3 process. Setting Fourteen virtual meetings and two in-person meetings held between May 2021 and June 2022. Main Outcome Measure(s) Identification and refinement of a countermeasure to develop and imbed a hearing health vital sign for adult hearing. Results Through a rigorous, structured A3 process, the Hearing Health Collaborative identified and refined the rationale for and the qualities associated with a public-facing vital sign for adult hearing loss. Specifically, such a vital sign must embody five qualities: simple, accessible, stable, inclusive, and meaningful. These qualities together would ensure that a hearing health vital sign would be useful not only as a screening tool but also as an instrument to guide next steps in workup and potentially treatment. Conclusions Successful identification and implementation of a hearing metric or “vital sign” for the presence of adult hearing loss, using precedent convention of other medical diseases, may help reframe public perceptions surrounding hearing loss, improve awareness and literacy regarding the presence of the disease, and prompt action to seek diagnostic assessment.
Access to Cochlear Implantation: Trends in Surgeon Volume and Training
Espahbodi, Mana , Trautwein, Patricia G., Bestourous, Daniel E. , Zwolan, Teresa A. , Nassiri, Ashley M. , Carlson, Matthew L. , Patel, Neil S. , Gurgel, Richard K. , Gurgel, Richard Klaus , Erbele, Isaac D.

The Laryngoscope | February 11, 2025 | Volume: 135 | Issue: 6 | Pages: 2146-2153

10.1002/lary.32037 Get It

Objectives Evaluate the training background of surgeons performing high volumes of cochlear implants (CIs) and estimate the ratio of providers trained in otology/neurotology (O&N) to the number of traditional CI candidates and audiologists. Methods A retrospective review of US surgeon registration data from a single CI manufacturer was performed to determine CI volume based on surgeon training. The prevalence of traditional candidates for CIs was estimated from US census population data and compared with the number of O&N providers. The ratio of audiologists to O&N providers was estimated from the Bureau of Labor and Statistics and American Speech‐Language‐Hearing Association databases. Results From 2021 to 2023, a mean of 88% of providers performing ≥25 CIs per year and 90% performing ≥40 per year had training in O&N. All surgeons registering ≥100 implants per year were O&N providers. The mean percentage of O&N providers performing ≥25 CIs per year and ≥ 40 per year was higher than the percentage of General and Pediatric Otolaryngology providers performing the same volume: mean difference = 76%, p < 0.001 and mean difference = 79%, p < 0.001, respectively. The mean estimated prevalence of traditional CI candidates per O&N provider is 3,354 with an estimated mean of 32 audiologists (3.5 trained in CIs) per O&N provider. Conclusion 88% of high‐volume CI surgeons have fellowship training in O&N. To meet the current state of CI underutilization and anticipated growing population of CI candidates, we propose increasing the surgical capacity of O&N providers and the number of surgeons proficient in CIs. Level of Evidence NA Laryngoscope , 135:2146–2153, 2025
Revised Classification of Inner Ear Schwannomas
Lloyd, Simon , Freeman, Simon , Kösling, S., Biggs, Nigel, Gubbels, Samuel P., Hess-Erga, Jeanette , Lohse, Christine M. , Marinelli, John P. , Micco, Riccardo Di , Nassiri, Ashley M. , Scheffler, Jonas , Cayé‐Thomasen, Per , Carlson, Matthew L., Plontke, Stefan K. , Arnoldner, Christoph , Borsetto, Daniele , Koo, Ja‐Won , Rahne, Torsten , Carlson, Matthew L.

Otology & Neurotology | October 30, 2024 | Volume: 46 | Issue: 1 | Pages: 3-9

10.1097/mao.0000000000004363 Get It

ABSTRACT Over the past two decades, there has been increasing interest in the diagnosis and management of schwannomas of the inner ear including hearing rehabilitation with cochlear implants. However, tumor nomenclature and classification within the literature have been variable and oftentimes cumbersome. The term “intralabyrinthine schwannoma” is in common use when describing these tumors but is a potential source of confusion given that people often use the term “labyrinth” or “labyrinthine” to refer to the vestibular component of the inner ear only (i.e., labyrinthectomy or the translabyrinthine approach). During the Ninth Quadrennial Conference on Vestibular Schwannoma and Other Cerebellopontine Angle Lesions in Bergen, Norway, in May 2023, a multidisciplinary group of conference participants met and discussed issues pertaining to current terminology and classifications to enhance clarity and to reflect recent advances in tumor management and hearing rehabilitation. Although a variety of terms have been previously used to describe inner ear schwannomas, consensus was achieved on the term “inner ear schwannoma (IES)” to describe eighth nerve schwannomas of the cochlea, vestibule, or semicircular canals. Subgroups under this term comprise intravestibular, intracochlear, or intravestibulocochlear inner ear schwannomas (low complexity tumors), inner ear schwannomas with transfundal extension into the internal auditory canal but without modiolar involvement (intermediate complexity tumors), and inner ear schwannomas with transfundal extension with modiolar involvement (high complexity tumors). The details of the recommendations for an updated and simplified tumor nomenclature centered around tumor control and hearing rehabilitation with cochlear implantation are presented.
Cochlear Implantation Outcomes in Patients With Sporadic Inner Ear Schwannomas With and Without Simultaneous Tumor Resection
Nassiri, Ashley M. , Staricha, Kelly L. , Neff, Brian A., Driscoll, Colin L. W., Link, Michael J. , Carlson, Matthew L. , Staricha, Kelly

Otology & Neurotology | August 9, 2024 | Volume: 45 | Issue: 9 | Pages: 1051-1054

10.1097/mao.0000000000004268 Get It

Objectives Describe a single institution's cochlear implant outcomes for patients with inner ear schwannomas (IES) in the setting of various tumor management strategies (observation, surgical resection, or stereotactic radiosurgery [SRS]). Study Design Single-institution retrospective review. Patients Patients diagnosed with isolated, sporadic IES who underwent cochlear implantation (CI). Interventions CI with or without IES treatment. Main Outcome Measures Speech perception outcomes, tumor status. Results Twelve patients with IES underwent CI with a median audiologic and radiologic follow-up of 12 months. Six patients underwent complete resection of the tumor at the time of CI, four underwent tumor observation, and two underwent SRS before CI. At 1 year after CI for all patients, the median consonant–nucleus–consonant (CNC) word score was 55% (interquartile range, 44–73%), and the median AzBio sentence in quiet score was 77% (interquartile range, 68–93%). Overall, those with surgical resection performed similarly to those with tumor observation (CNC 58 versus 61%; AzBio in quiet 74 versus 91%, respectively). Patients who underwent tumor resection before implantation had a wider range of speech performance outcomes compared with patients who underwent tumor observation. Two patients had SRS treatment before CI (10 months previous and same-day as CI) with CNC word scores of 6 and 40%, respectively. Conclusions Patients with IES who underwent CI demonstrated similar speech performance outcomes (CNC 56% and AzBio 82%), when compared with the general cochlear implant population. Patients who underwent either tumor observation or surgical resection performed well after CI.
Anatomical Step-by-Step Dissection of Complex Skull Base Approaches for Trainees: Surgical Anatomy of the Translabyrinthine and Transcochlear Approaches
Perry, Avital , Carlstrom, Lucas P. , Alexander, A. Yohan , Leonel, Luciano, Nassiri, Ashley M. , Nguyen, Bachtri T. , Driscoll, Colin L. W., Link, Michael J. , Graffeo, Christopher S. , Peris‐Celda, Maria , Alexander, Alex Yohan, Nguyen, Bachtri , Graffeo, Christopher Salvatore , Alexander, A Yohan , Morris, Jonathan M.

Journal of Neurological Surgery Part B: Skull Base | May 13, 2024 | Volume: 86 | Issue: 03 | Pages: 342-352

10.1055/s-0044-1786736 Get It

Abstract Introduction Skull base neuroanatomy is traditionally learned through two-dimensional anatomical atlases, which while are of unquestionable value, lack the nuanced association of three-dimensional relationships between fundamental anatomical structures relevant to surgical approaches. Surgically focused step-by-step anatomical dissections can augment trainee learning of complex skull base techniques, particularly multistep and nuanced techniques such as translabyrinthine and transcochlear approaches. Methods Translabyrinthine and transcochlear approaches were performed on six sides of three formalin-fixed latex-injected specimens. The study objective was the completion and photo documentation of the steps involved in the approach in order to provide a comprehensive, intelligible, and anatomically oriented resource for multilevel trainees. Illustrative case examples were prepared to supplement approach dissections. Results The translabyrinthine and transcochlear approaches offer unique lateral windows through the temporal bone into the posterior fossa, providing excellent access to pathology at the petrous apex, internal auditory canal, Meckel's cave, and anterolateral brainstem. The transcochlear approach, which is an anterior extension of the translabyrinthine, particularly provides excellent exposure of the prepontine region and clivus. Important surgical considerations include patient position, temporal bone drilling and identification of critical landmarks, dural opening and identification of neurovascular structures, and reconstruction/closure techniques. Conclusion The translabyrinthine and transcochlear approaches are fundamental techniques for lateral skull base and posterior fossa pathologies. Both approaches are hearing-sacrificing but often require minimal to no cerebellar retraction and deliver unique visualization of prepontine neurovascular structures. This step-by-step approach guide provides a unique practical and high-yield surgically oriented learning resource for neurosurgery and otolaryngology trainees.
Full Recovery of Hearing After Resection of a Large Epidermoid Tumor at the Cerebellopontine Angle: 2-Dimensional Operative Video
Bauman, Megan M. J. , Nassiri, Ashley M. , Driscoll, Colin L. W., Link, Michael J. , Driscoll, Colin L., Bauman, Megan

Operative Neurosurgery | May 8, 2024 | Volume: 27 | Issue: 5 | Pages: 672-672

10.1227/ons.0000000000001202 Get It

Anatomic Step-by-Step Dissection of Complex Skull Base Approaches for Trainees: Surgical Anatomy of the Infratemporal Fossa Approach to the Jugular Foramen
Dornhoffer, James R. , Nassiri, Ashley M. , Peris‐Celda, Maria , Leonel, Luciano, Carlson, Matthew L. , Leonel, Luciano C

Operative Neurosurgery | November 17, 2023 | Volume: 26 | Issue: 4 | Pages: 452-462

10.1227/ons.0000000000000996 Get It

BACKGROUND AND OBJECTIVES: The infratemporal fossa (ITF) is a complex region bounded by the temporal bone, maxilla, sphenoid, pterygoid plates, and mandibular ramus. Containing a high density of neurovascular and musculoskeletal structures, the ITF can house a number of pathologies, and access is challenging. The ITF approach and its variations can be challenging due to complex anatomy and unfamiliarity by many surgeons. The objective of this study was to present a step-by-step 3-dimensional anatomic dissection for the classic Fisch Type A and modified ITF approach from the surgeon's perspective. METHODS: Six sides of 3 formalin-fixed latex-injected specimens were dissected under microscopic magnification (JRD and AMN). Standard Fisch Type A and modified ITF approaches were performed on contralateral sides of each specimen. Representative high-quality 3-dimensional photography was performed for each key step. RESULTS: The ITF approach affords excellent access to the posterior ITF and jugular foramen. Modifications to this approach include preservation of the ear canal and limiting facial nerve transposition, thus limiting morbidity while generally still providing sufficient access to key anatomic structures. CONCLUSION: The ITF approach provides access to the lateral skull base for jugular foramen paraganglioma and other lesions. Modifications of the classic Fisch Type A technique can be used to access pathologies in this region without sacrificing conductive hearing or facial nerve function. Three dimensional operatively oriented neuroanatomy dissections provide surgeons with a valuable resource for learning this complex surgical approach.