The Experts below are selected from a list of 195 Experts worldwide ranked by ideXlab platform

Donlin M. Long - One of the best experts on this subject based on the ideXlab platform.

  • Microanatomical variations in the cerebellopontine angle associated with vestibular schwannomas (acoustic neuromas): a retrospective study of 1006 consecutive cases.
    Journal of neurosurgery, 2000
    Co-Authors: Prakash Sampath, David A. Rini, Donlin M. Long
    Abstract:

    Object. Great advances in neuroimaging, intraoperative Cranial Nerve Monitoring, and microsurgical technique have shifted the focus of acoustic neuroma surgery from prolonging life to preserving Cranial Nerve function in patients. An appreciation of the vascular and Cranial Nerve microanatomy and the intimate relationship between neurovascular structures and the tumor is essential to achieve optimum results. In this paper the authors analyze the microanatomical variations in location of the facial and cochlear Nerves in the cerebellopontine angle (CPA) associated with acoustic neuromas and, additionally, describe the frequency of involvement of surrounding neural and vascular structures with acoustic tumors of varying size. The authors base these findings on their experience with 1006 consecutive patients who underwent surgery via a retrosigmoid or translabyrinthine approach. Methods. Between July 1969 and January 1998, the senior author (D.M.L.) performed surgery in 1022 patients for acoustic neuroma: 70...

  • Microanatomical variations in the cerebellopontine angle associated with vestibular schwannomas (acoustic neuromas)
    Neurosurgical Focus, 1998
    Co-Authors: Prakash Sampath, David Rini, Donlin M. Long
    Abstract:

    Great advances in neuroimaging, intraoperative Cranial Nerve Monitoring, and microsurgical technique have shifted the focus of acoustic neuroma surgery from prolonging life to preserving Cranial Nerve function in patients. An appreciation of the vascular and Cranial Nerve microanatomy and the intimate relationship between neurovascular structures and the tumor is essential to achieve optimum results. In this paper the authors analyze the microanatomical variations in location of the facial and cochlear Nerves in the cerebellopontine angle (CPA) associated with acoustic neuromas and, additionally, describe the frequency of involvement of surrounding neural and vascular structures with acoustic tumors of varying size. The authors base their findings on their experience treating 1006 consecutive patients who underwent surgery via a retrosigmoid or translabyrinthine approach. Between July 1969 and January 1998, the senior author (D.M.L.) performed surgery in 1022 patients for acoustic neuroma: 705 (69%) via t...

Bernard Bendok - One of the best experts on this subject based on the ideXlab platform.

  • Insertion of intra-oral electrodes for Cranial Nerve Monitoring using a Crowe–Davis retractor
    Journal of Clinical Monitoring and Computing, 2017
    Co-Authors: Terrence L. Trentman, Christopher Thunberg, Andrew Gorlin, Antoun Koht, Richard S. Zimmerman, Bernard Bendok
    Abstract:

    Acoustic neuroma resection is an example of a neurosurgical procedure where the brainstem and multiple Cranial Nerves are at risk for injury. Electrode placement for Monitoring of the glossopharyngeal and hypoglossal Nerves during acoustic neuroma resection can be challenging. The purpose of this report is to illustrate the use of a device for intra-oral electrode placement for intraoperative Monitoring of the glossopharyngeal and hypoglossal Nerves. A 60-year-old male presented for acoustic neuroma resection. Under general anesthesia, a Crowe–Davis retractor was used to open the mouth, providing access to the posterior pharynx. For glossopharyngeal Monitoring, two bent subdermal needle electrodes were inserted just lateral to the uvula. Two additional electrodes were inserted on the lateral tongue to monitor the hypoglossal Nerve. Cranial Nerves Monitoring was conducted utilizing both free running and triggered electromyography of the trigeminal and facial Nerves in addition to the lower Cranial Nerves. The tumor was resected successfully. Monitoring of the Cranial Nerves (including the glossopharyngeal and hypoglossal Nerves) revealed no concerning responses. The Crowe–Davis retractor and the technique described allowed insertion of electrodes for neural Monitoring, contributing to neural preservation.

  • Insertion of intra-oral electrodes for Cranial Nerve Monitoring using a Crowe-Davis retractor.
    Journal of clinical monitoring and computing, 2016
    Co-Authors: Terrence L. Trentman, Christopher Thunberg, Antoun Koht, Richard S. Zimmerman, Andrew W Gorlin, Bernard Bendok
    Abstract:

    Acoustic neuroma resection is an example of a neurosurgical procedure where the brainstem and multiple Cranial Nerves are at risk for injury. Electrode placement for Monitoring of the glossopharyngeal and hypoglossal Nerves during acoustic neuroma resection can be challenging. The purpose of this report is to illustrate the use of a device for intra-oral electrode placement for intraoperative Monitoring of the glossopharyngeal and hypoglossal Nerves. A 60-year-old male presented for acoustic neuroma resection. Under general anesthesia, a Crowe-Davis retractor was used to open the mouth, providing access to the posterior pharynx. For glossopharyngeal Monitoring, two bent subdermal needle electrodes were inserted just lateral to the uvula. Two additional electrodes were inserted on the lateral tongue to monitor the hypoglossal Nerve. Cranial Nerves Monitoring was conducted utilizing both free running and triggered electromyography of the trigeminal and facial Nerves in addition to the lower Cranial Nerves. The tumor was resected successfully. Monitoring of the Cranial Nerves (including the glossopharyngeal and hypoglossal Nerves) revealed no concerning responses. The Crowe-Davis retractor and the technique described allowed insertion of electrodes for neural Monitoring, contributing to neural preservation.

Prakash Sampath - One of the best experts on this subject based on the ideXlab platform.

  • Microanatomical variations in the cerebellopontine angle associated with vestibular schwannomas (acoustic neuromas): a retrospective study of 1006 consecutive cases.
    Journal of neurosurgery, 2000
    Co-Authors: Prakash Sampath, David A. Rini, Donlin M. Long
    Abstract:

    Object. Great advances in neuroimaging, intraoperative Cranial Nerve Monitoring, and microsurgical technique have shifted the focus of acoustic neuroma surgery from prolonging life to preserving Cranial Nerve function in patients. An appreciation of the vascular and Cranial Nerve microanatomy and the intimate relationship between neurovascular structures and the tumor is essential to achieve optimum results. In this paper the authors analyze the microanatomical variations in location of the facial and cochlear Nerves in the cerebellopontine angle (CPA) associated with acoustic neuromas and, additionally, describe the frequency of involvement of surrounding neural and vascular structures with acoustic tumors of varying size. The authors base these findings on their experience with 1006 consecutive patients who underwent surgery via a retrosigmoid or translabyrinthine approach. Methods. Between July 1969 and January 1998, the senior author (D.M.L.) performed surgery in 1022 patients for acoustic neuroma: 70...

  • Microanatomical variations in the cerebellopontine angle associated with vestibular schwannomas (acoustic neuromas)
    Neurosurgical Focus, 1998
    Co-Authors: Prakash Sampath, David Rini, Donlin M. Long
    Abstract:

    Great advances in neuroimaging, intraoperative Cranial Nerve Monitoring, and microsurgical technique have shifted the focus of acoustic neuroma surgery from prolonging life to preserving Cranial Nerve function in patients. An appreciation of the vascular and Cranial Nerve microanatomy and the intimate relationship between neurovascular structures and the tumor is essential to achieve optimum results. In this paper the authors analyze the microanatomical variations in location of the facial and cochlear Nerves in the cerebellopontine angle (CPA) associated with acoustic neuromas and, additionally, describe the frequency of involvement of surrounding neural and vascular structures with acoustic tumors of varying size. The authors base their findings on their experience treating 1006 consecutive patients who underwent surgery via a retrosigmoid or translabyrinthine approach. Between July 1969 and January 1998, the senior author (D.M.L.) performed surgery in 1022 patients for acoustic neuroma: 705 (69%) via t...

Jeffrey J Olson - One of the best experts on this subject based on the ideXlab platform.

  • congress of neurological surgeons systematic review and evidence based guidelines on intraoperative Cranial Nerve Monitoring in vestibular schwannoma surgery
    Neurosurgery, 2018
    Co-Authors: Esther X Vivas, Matthew L Carlson, Brian A Neff, Neil T Shepard, Jay D Mccracken, Alex D Sweeney, Jeffrey J Olson
    Abstract:

    Question 1: Does intraoperative facial Nerve Monitoring during vestibular schwannoma surgery lead to better long-term facial Nerve function? Target Population: This recommendation applies to adult patients undergoing vestibular schwannoma surgery regardless of tumor characteristics. Recommendation: Level 3: It is recommended that intraoperative facial Nerve Monitoring be routinely utilized during vestibular schwannoma surgery to improve long-term facial Nerve function. Question 2: Can intraoperative facial Nerve Monitoring be used to accurately predict favorable long-term facial Nerve function after vestibular schwannoma surgery? Target Population: This recommendation applies to adult patients undergoing vestibular schwannoma surgery. Recommendation: Level 3: Intraoperative facial Nerve can be used to accurately predict favorable long-term facial Nerve function after vestibular schwannoma surgery. Specifically, the presence of favorable testing reliably portends a good long-term facial Nerve outcome. However, the absence of favorable testing in the setting of an anatomically intact facial Nerve does not reliably predict poor long-term function and therefore cannot be used to direct decision-making regarding the need for early reinnervation procedures. Question 3: Does an anatomically intact facial Nerve with poor electromyogram (EMG) electrical responses during intraoperative testing reliably predict poor long-term facial Nerve function? Target Population: This recommendation applies to adult patients undergoing vestibular schwannoma surgery. Recommendation: Level 3: Poor intraoperative EMG electrical response of the facial Nerve should not be used as a reliable predictor of poor long-term facial Nerve function. Question 4: Should intraoperative eighth Cranial Nerve Monitoring be used during vestibular schwannoma surgery? Target Population: This recommendation applies to adult patients undergoing vestibular schwannoma surgery with measurable preoperative hearing levels and tumors smaller than 1.5 cm. Recommendation: Level 3: Intraoperative eighth Cranial Nerve Monitoring should be used during vestibular schwannoma surgery when hearing preservation is attempted. Question 5: Is direct Monitoring of the eighth Cranial Nerve superior to the use of far-field auditory brain stem responses? Target Population: This recommendation applies to adult patients undergoing vestibular schwannoma surgery with measurable preoperative hearing levels and tumors smaller than 1.5 cm. Recommendation: Level 3: There is insufficient evidence to make a definitive recommendation.  The full guideline can be found at: https://www.cns.org/guidelines/guidelines-manage-ment-patients-vestibular-schwannoma/chapter_4.

Charles D. Yingling - One of the best experts on this subject based on the ideXlab platform.

  • Comparison of response amplitude versus stimulation threshold in predicting early postoperative facial Nerve function after acoustic neuroma resection.
    The American journal of otology, 1998
    Co-Authors: A. H. Mandpe, Robert K. Jackler, Lawrence H. Pitts, A. Mikulec, Charles D. Yingling
    Abstract:

    Objective: This study aimed to better predict the early postoperative facial Nerve (FN) function after acoustic neuroma (AN) resection. Study Design: This study was a prospective series. Setting: The surgery was conducted in a tertiary referral center. Patients: A total of 44 patients undergoing AN resection with Cranial Nerve Monitoring were observed for at least 1 year after surgery. Main Outcome Measures: The predictive value of amplitude of the FN stimulus response on the early postoperative FN function was measured. Results: Cranial Nerve Monitoring in AN surgery was used to obtain the stimulation threshold and facial electromyograph response amplitudes to FN stimulation proximal and distal to the tumor at 0.2 V above threshold. Thirty-eight of forty-four patients studied had a low postresection threshold (≤ 0.1 V). Of these (10), 26% sustained a postoperative FN dysfunction of House-Brackmann (HB) grades 3-6. In an effort to improve the predictive value from Cranial Nerve Monitoring, the response amplitude to suprathreshold stimulation was compared with the threshold and FN function. Eighty-nine percent of patients with an amplitude of ≥200 μV had a grade 1-2 early postoperative FN function, whereas only 41% of patients with < 200 μV had a grade 1-2 early postoperative FN function (p = 0.00035). Eighty-eight percent of patients with both a low threshold and high amplitude had a grade 1-2 early postoperative FN function, whereas the remaining 12% of patients had a grade 3-6 FN function (p = 0.0032). The false-positive rate of threshold alone in predicting a grade 1-2 FN function was 26% compared to 12% for low threshold and high amplitude combined. Conclusions: The use of FN threshold and amplitude together is superior to threshold alone as a predictor of early postoperative FN function.

  • Delayed onset facial Nerve dysfunction following acoustic neuroma surgery.
    The American journal of otology, 1995
    Co-Authors: Anil K. Lalwani, Fidelia Yuan-shin Butt, Robert K. Jackler, Lawrence H. Pitts, Charles D. Yingling
    Abstract:

    Delayed onset facial Nerve dysfunction following acoustic neuroma surgery is an under-appreciated phenomenon. The authors have recently reviewed long-term (>1 year) facial Nerve outcome in 129 patients who underwent acoustic neuroma removal with the aid of Cranial Nerve Monitoring between 1986 and 1990. The facial Nerve was anatomically preserved in 99.2% of the patients, and at one year, 90% of all the patients had House-Brackmann (H-B) grade I or II facial Nerve function. Delayed onset worsening of facial Nerve function was noted in 38 of 129 (29%) patients, most of which occurred in the first few postoperative days. The incidence increases to 41% (38 of 93) when corrected for those with immediate H-B grade VI weakness, and who therefore could not manifest further deterioration. The facial Nerve function either deteriorated from normal to abnormal or increased in severity of weakness. Delayed facial palsy was not related to the size of tumor or the surgical approach. The most common occurrence was that of a patient with H-B grade I or II facial Nerve function worsening to H-B grade VI in the postoperative period. The prognosis for recovery of facial Nerve function following delayed palsy was excellent. In the majority of cases, the recovery was complete within the first 6 months without specific treatment. Comparable to the patients without delayed palsies, 89% (34 of 38) of the cases had H-B grade I or II and 97% (37 of 38) had H-B grade III or better facial Nerve function at 1 year. This review suggests a surprisingly high incidence of delayed facial palsy following acoustic neuroma surgery, which fortunately has an excellent prognosis for spontaneous recovery.

  • facial Nerve outcome after acoustic neuroma surgery a study from the era of Cranial Nerve Monitoring
    Otolaryngology-Head and Neck Surgery, 1994
    Co-Authors: Anil K. Lalwani, Fidelia Yuan-shin Butt, Robert K. Jackler, Lawrence H. Pitts, Charles D. Yingling
    Abstract:

    The introduction of intraoperative Cranial Nerve Monitoring in posterior fossa surgery has greatly aided the surgeon in identification and anatomic preservation of Cranial Nerves. As a result, the long-term function of the facial Nerve continues to improve after removal of acoustic neuroma. Herein, we report our long-term (1 year or greater) facial Nerve outcome in 129 patients who underwent surgical removal of their acoustic neuromas with the aid of intraoperative neurophysiologic Monitoring between 1986 and 1990. The facial Nerve was anatomically preserved in 99.2% of the patients, and 90% of all the patients had grade 1 or 2 facial Nerve function 1 year after surgery. Long-term facial function was inversely correlated with the size of tumor (chi-squared, p < 0.02) and was not related to the side of tumor, the age and sex of the patient, or the surgical approach. In a comparison among tumor groups matched for size, no statistically significant difference in facial Nerve outcome between the translabyrinthine and retrosigmoid approaches was detected. The proximal facial Nerve stimulation threshold at the end of surgical removal was predictive of long-term facial Nerve function (analysis of variance, p < 0.02). At 1 year, 98% (87 of 89) of the patients with electrical thresholds of 0.2 V or less had grade 1 or 2 facial Nerve function compared with only 50% (8 of 16) of those with thresholds between 0.21 and 0.6 V. In the era of Cranial Nerve Monitoring, patients can be better advised about long-term facial Nerve outcome after surgical intervention. Preoperatively, the size of the tumor is the most critical factor in predicting long-term facial function. Postoperatively, the proximal seventh Nerve stimulation threshold at the end of the surgical procedure can be used as one prognostic measure of long-term facial Nerve function.

  • Facial Nerve outcome after acoustic neuroma surgery: a study from the era of Cranial Nerve Monitoring.
    Otolaryngology--head and neck surgery : official journal of American Academy of Otolaryngology-Head and Neck Surgery, 1994
    Co-Authors: Anil K. Lalwani, Fidelia Yuan-shin Butt, Robert K. Jackler, Lawrence H. Pitts, Charles D. Yingling
    Abstract:

    The introduction of intraoperative Cranial Nerve Monitoring in posterior fossa surgery has greatly aided the surgeon in identification and anatomic preservation of Cranial Nerves. As a result, the ...