Publications by authors named "Michael J Link"

Objective: The floor of the third ventricle and the interpeduncular and prepontine regions represent challenging surgical targets. The expanded endoscopic endonasal approach (EEA) with pituitary gland (PG) transposition has been proposed to provide direct access to these anatomical regions. Through the years, different endoscopic PG transposition techniques have been studied and presented.

View Article and Find Full Text PDF

Objective: To compare the utility of intraoperative electrically evoked auditory brainstem response (eABR) and electrically evoked stapedial reflex testing (eSRT) for cochlear nerve integrity monitoring during simultaneous translabyrinthine resection of vestibular schwannoma (VS) and cochlear implantation.

Study Design: Historical cohort study.

Setting: Tertiary academic referral center.

View Article and Find Full Text PDF

The Simons Observatory (SO) is a cosmic microwave background instrumentation suite in the Atacama Desert of Chile. More than 65,000 polarization-sensitive transition-edge sensor (TES) bolometers will be fielded in the frequency range spanning 27 to 280 GHz, with three separate dichroic designs. The mid-frequency 90/150 GHz and ultra-high-frequency 220/280 GHz detector arrays, fabricated at NIST, account for 39 of 49 total detector modules and implement the feedhorn-fed orthomode transducer-coupled TES bolometer architecture.

View Article and Find Full Text PDF
Article Synopsis
  • The study aims to evaluate how different cochlear dose parameters affect hearing outcomes in patients with sporadic vestibular schwannoma (VS) who have serviceable hearing after undergoing stereotactic radiosurgery (SRS).
  • A total of 205 patients were analyzed over a period from 2007 to 2022, revealing that 62% of patients maintained serviceable hearing at 2 years, while this dropped to 15% by 10 years post-treatment.
  • Results showed a significant association between increased minimum cochlear dose and faster decline in hearing, indicating that this dose parameter should be a key consideration in planning radiosurgery for VS patients.
View Article and Find Full Text PDF

Objective: Stereotactic radiosurgery (SRS) is increasingly used for small-to-medium-sized sporadic vestibular schwannoma (VS) and is associated with good tumor control and low-risk of adverse radiation-associated events. The exact mechanism of VS tumor control is unknown but may relate to microvascular hyalinization and resultant tumoral ischemia. This study examined associations of microvascular risk factors with outcomes following SRS.

View Article and Find Full Text PDF
Article Synopsis
  • * A detailed guide has been created to assist trainees by describing key steps such as patient positioning, incision techniques, and necessary craniofacial modifications.
  • * The study involved dissecting specimens and documenting the procedure with three-dimensional photography to provide clear illustrations and enhance understanding of this surgical approach for education and training purposes.
View Article and Find Full Text PDF

 The American Association of Neurological Surgeons (AANS), North American Skull Base Society (NASBS), American Rhinologic Society (ARS), and American Neurotology Society (ANS) fellowship directories are important information repositories for skull base surgical fellowship programs. However, there is limited research on the amount and depth of information available through these resources. The objective of the present study is to assess Web site accessibility and information availability for individual fellowship programs listed within the AANS, NASBS, ARS, and ANS fellowship directories.

View Article and Find Full Text PDF

Objective: To evaluate the long-term changes in sporadic vestibular schwannoma (VS) disease-specific quality-of-life (QOL) outcomes.

Study Design: Prospective longitudinal study using the Penn Acoustic Neuroma Quality of Life (PANQOL) Scale.

Setting: National survey.

View Article and Find Full Text PDF
Article Synopsis
  • This study investigates the effectiveness of a "wait-and-scan" approach using MRI for managing patients with small to medium-sized vestibular schwannomas (VS), aiming to assess patient adherence to follow-up.
  • Over six years, 270 patients were tracked, revealing that 27% were completely lost to follow-up before receiving treatment, while another 22% missed scheduled MRI follow-ups.
  • The research identified key factors for loss to follow-up, including living out of state and having smaller tumor sizes, indicating that distance and tumor characteristics significantly impact patient adherence to recommended imaging surveillance.
View Article and Find Full Text PDF

Objective: The role of stereotactic radiosurgery (SRS) in the management of intracranial dural arteriovenous fistula (dAVF) is unclear given the rarity of this lesion and the variability in treatment paradigms. This study describes a 3-decade experience with the SRS technique and its outcomes for patients with dAVF.

Methods: The authors conducted a retrospective analysis of patients with dAVF who had undergone single-fraction SRS in the period from 1990 to 2021.

View Article and Find Full Text PDF

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).

View Article and Find Full Text PDF

Background And Objectives: The trans-sinus transglabellar and bifrontal approaches offer direct access to the anterior cranial fossa. However, these approaches present potential drawbacks. We propose the biportal endoscopic transfrontal sinus (BETS) approach, adapting endoscopic endonasal approach (EEA) techniques for minimally invasive access to the anterior fossa, reducing tissue manipulation, venous sacrifice, and brain retraction.

View Article and Find Full Text PDF

Photogrammetry scans has directed attention to the development of advanced camera systems to improve the creation of three-dimensional (3D) models, especially for educational and medical-related purposes. This could be a potential cost-effective method for neuroanatomy education, especially when access to laboratory-based learning is limited. The aim of this study was to describe a new photogrammetry system based on a 5 Digital Single-Lens Reflex (DSLR) cameras setup to optimize accuracy of neuroanatomical 3D models.

View Article and Find Full Text PDF
Article Synopsis
  • The study investigates the potential long-term effects of radiation treatment, particularly focusing on the rare occurrence of radiation-induced vestibular schwannomas (VSs) among patients who received radiation that covered the posterior fossa.* -
  • A review of eight cases revealed that patients had a median age of 15 years at the time of radiation and were diagnosed with VS a median of 51 years later, with some tumor characteristics noted, such as adherence to the facial nerve.* -
  • The findings suggest that while the occurrence of radiation-induced VS is rare, more research is needed to understand its causative relationship with radiation exposure and to improve management strategies for affected patients.*
View Article and Find Full Text PDF

White matter dissection (WMD) involves isolating bundles of myelinated axons in the brain and serves to gain insights into brain function and neural mechanisms underlying neurological disorders. While effective, cadaveric brain dissections pose certain challenges mainly due to availability of resources. Technological advancements, such as photogrammetry, have the potential to overcome these limitations by creating detailed three-dimensional (3D) models for immersive learning experiences in neuroanatomy.

View Article and Find Full Text PDF

Objective: To describe outcomes of patients with sporadic vestibular schwannoma (VS) who underwent repeat stereotactic radiosurgery (SRS) after primary SRS failure.

Study Design: Multi-institutional historical cohort study.

Setting: Five tertiary care referral centers.

View Article and Find Full Text PDF

Objective: This study aimed to provide data on extended outcomes in primary clival chordomas, focusing on progression-free survival (PFS) and overall survival (OS).

Methods: A retrospective single-center analysis was conducted on patients with clival chordoma treated between 1987 and 2022 using surgery, stereotactic radiosurgery, or proton radiation therapy (PRT).

Results: The study included 100 patients (median age 44 years, 51% male).

View Article and Find Full Text PDF

Objective: To assess the impact of tumor extension into the occipital condyle (OC) in lower clival chordoma management and the need for occipito-cervical fusion (OCF).

Methods: A retrospective analysis was conducted on 35 patients with lower clival chordoma. The preoperative area of the intact OCs, Hounsfield units, and the integrity of the apical ligament and the tectorial membrane were assessed using preoperative imaging.

View Article and Find Full Text PDF

Objective: The objective of this study was to describe the quantitative features of intraoperative electromyographic recordings obtained from cranial nerve III, IV, and VI neuromonitoring using 25-mm intraorbital electrodes, in the larger context of demonstrating the practicality of this technique during neurosurgical cases.

Methods: A 25-mm-long shaft-insulated intraorbital needle electrode is routinely used at the authors' institution for extraocular muscle (EOM) electromyographic monitoring of the inferior rectus, superior oblique, and/or lateral rectus muscles when their function is at risk. Cases monitored between January 1, 2021, and December 31, 2022, were reviewed for patient demographics, tumor location and pathology, EOMs monitored, pre- and postoperative examination, and complications from electrode placement.

View Article and Find Full Text PDF

Background: Spindle cell oncocytomas (SCO) and granular cell tumors (GCT) are rare primary pituitary neoplasms; the optimal treatment paradigms for these lesions are unknown and largely unexplored. Thus, using national registries, we analyze the epidemiology, management patterns, and surgical outcomes of SCOs and GCTs.

Methods: The National Cancer Database (NCDB; years 2003-2017) and the Surveillance, Epidemiology, and End Results Program (SEER; years 2004-2018) were queried for patients with pituitary SCOs or GCTs.

View Article and Find Full Text PDF

Background And Objectives: The retrosigmoid approach with transtentorial extension (RTA) allows us to address posterior cranial fossa pathologies that extend through the tentorium into the supratentorial space. Incision of the tentorium cerebelli is challenging, especially for the risk of injury of the cranial nerve (CN) IV. We describe a tentorial incision technique and relevant anatomic landmarks.

View Article and Find Full Text PDF

Noninvasive tumor control of vestibular schwannomas through stereotactic radiosurgery allows high rates of long-term tumor control and has been used primarily for small- and medium-sized vestibular schwannomas. The posttreatment imaging appearance of the tumor, temporal patterns of growth and treatment response, as well as extratumoral complications can often be both subtle or confusing and should be appropriately recognized. Herein, the authors present an imaging-based review of expected changes as well as associated complications related to radiosurgery for vestibular schwannomas.

View Article and Find Full Text PDF