Hearing conservation in acoustic neuroma surgery via the posterior fossa

Baldwin, David L.; King, T. T.; Morrison, A. W.

doi:10.1017/s0022215100112897

Cited by 46 publications

(13 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It has been suggested that hearing itself should be evaluated by a combination of pure-tone audiometric findings and speech discrimination score. 7,16 In our previous communication, we proposed that data on the following ten items should be given for consistent evaluationl4: (1) surgical approach; (2) the total number of cases; (3) the incidence of tumors extending 20 mm or less into the posterior fossa; (4) the number of cases of attempted hearing preservation; (5) the number of cases with hearing preserved; (6) the number of cases with 50/50 hearing preoperatively; (7) the number of cases with a tumor of 20 mm in diameter or smaller and 50/50 hearing postoperatively; (9) the number of cases with a tumor of 20 mm in diameter or smaller preoperatively and the 50/50 hearing postoperatively; and (10) the duration of postoperative follow-up. Unfortunately, only a few studies have given the information in all these categories.…”

Section: Facial Nerve Preservationmentioning

confidence: 99%

Hearing Preservation by the Extended and Nonextended Middle Cranial Fossa Approach for Acoustic Neuroma

Kanzaki¹,

O‐Uchi²,

Ogawa³

et al. 1994

Skull Base

View full text Add to dashboard Cite

Hearing preservation has recently become a topic of concern in the treatment of acoustic neuroma for the following reasons: (1) the mortality rate in acoustic neuroma surgery has decreased; (2) the facial nerve preservation rate has improved; (3) more cases are presenting with good hearing because of increased early diagnosis; (4) it is still difficult to preserve hearing in cases of neurofibromatosis type 2 (NF2); and (5)

show abstract

Section: Facial Nerve Preservationmentioning

confidence: 99%

Hearing Preservation by the Extended and Nonextended Middle Cranial Fossa Approach for Acoustic Neuroma

Kanzaki¹,

O‐Uchi²,

Ogawa³

et al. 1994

Skull Base

View full text Add to dashboard Cite

show abstract

“…6,30,32,50,51,56,62,77,78,86,92 Glasscock and others submitted that no patient should be excluded from surgery based on tumor size alone. 7,36,55,97 Several groups have supported this position, declaring that aggressive tumor removal as early as possible provides the greatest chance of hearing preservation.…”

mentioning

confidence: 99%

Surgery for vestibular schwannomas: a systematic review of complications by approach

Ansari

Terry

Cohen-Gadol

2012

FOC

249

216

View full text Add to dashboard Cite

Object Various studies report outcomes of vestibular schwannoma (VS) surgery, but few studies have compared outcomes across the various approaches. The authors conducted a systematic review of the available data on VS surgery, comparing the different approaches and their associated complications. Methods MEDLINE searches were conducted to collect studies that reported information on patients undergoing VS surgery. The authors set inclusion criteria for such studies, including the availability of follow-up data for at least 3 months, inclusion of preoperative and postoperative audiometric data, intraoperative monitoring, and reporting of results using established and standardized metrics. Data were collected on hearing loss, facial nerve dysfunction, persistent postoperative headache, CSF leak, operative mortality, residual tumor, tumor recurrence, cranial nerve (CN) dysfunction involving nerves other than CN VII or VIII, and other neurological complications. The authors reviewed data from 35 studies pertaining to 5064 patients who had undergone VS surgery. Results The analyses for hearing loss and facial nerve dysfunction were stratified into the following tumor categories: intracanalicular (IC), size (extrameatal diameter) < 1.5 cm, size 1.5–3.0 cm, and size > 3.0 cm. The middle cranial fossa approach was found to be superior to the retrosigmoid approach for hearing preservation in patients with tumors < 1.5 cm (hearing loss in 43.6% vs 64.3%, p < 0.001). All other size categories showed no significant difference between middle cranial fossa and retrosigmoid approaches with respect to hearing loss. The retrosigmoid approach was associated with significantly less facial nerve dysfunction in patients with IC tumors than the middle cranial fossa method was; however, neither differed significantly from the translabyrinthine corridor (4%, 16.7%, 0%, respectively, p < 0.001). The middle cranial fossa approach differed significantly from the translabyrinthine approach for patients with tumors < 1.5 cm, whereas neither differed from the retrosigmoid approach (3.3%, 11.5%, and 7.2%, respectively, p = 0.001). The retrosigmoid approach involved less facial nerve dysfunction than the middle cranial fossa or translabyrinthine approaches for tumors 1.5–3.0 cm (6.1%, 17.3%, and 15.8%, respectively; p < 0.001). The retrosigmoid approach was also superior to the translabyrinthine approach for tumors > 3.0 cm (30.2% vs 42.5%, respectively, p < 0.001). Postoperative headache was significantly more likely after the retrosigmoid approach than after the translabyrinthine approach, but neither differed significantly from the middle cranial fossa approach (17.3%, 0%, and 8%, respectively; p < 0.001). The incidence of CSF leak was significantly greater after the retrosigmoid approach than after either the middle cranial fossa or translabyrinthine approaches (10.3%, 5.3%, 7.1%; p = 0.001). The incidences of residual tumor, mortality, major non-CN complications, residual tumor, tumor recurrence, and dysfunction of other cranial nerves were not significantly different across the approaches. Conclusions The middle cranial fossa approach seems safest for hearing preservation in patients with smaller tumors. Based on the data, the retrosigmoid approach seems to be the most versatile corridor for facial nerve preservation for most tumor sizes, but it is associated with a higher risk of postoperative pain and CSF fistula. The translabyrinthine approach is associated with complete hearing loss but may be useful for patients with large tumors and poor preoperative hearing.

show abstract

“…Furthermore, it is exceedingly rare that the cochlear nerve passes through the tumor itself. In recent years much attention has been placed on attempts to preserve hearing in patients with good-to-moderate preoperative function, [2,7,12,16,23,27,34] especially regarding the inverse relationship between the size of acoustic tumors and postoperative hearing outcome. [12,27,40] In our experience, we find that preservation of functional hearing is a realistic goal even in patients with larger tumors (Groups 2 and 3), but predicting the patient's ultimate hearing status on the basis of anatomical preservation of the cochlear nerve and intraoperative BAEP monitoring is much less predictable.…”

Section: Discussionmentioning

confidence: 99%

“…In recent years, great advances in neuroimaging, cranial nerve monitoring, and microsurgery have shifted the focus of acoustic neuroma surgery from prolongation of patient life to preservation of cranial nerve function, [37] which has led to extraordinary improvements in patient outcomes, with reports from modern series of up to 90% postoperative normal or near-normal facial nerve function [1,3,19,22,25,33,36] and 40% hearing preservation. [2,7,12,15,16,21,23,27,34] A significant number of patients, however, still develop postoperative cranial nerve dysfunction. Consequently, further efforts to refine operative techniques and improve intraoperative monitoring to preserve maximum cranial nerve function continue to be made.…”

mentioning

confidence: 99%

Microanatomical variations in the cerebellopontine angle associated with vestibular schwannomas (acoustic neuromas)

Sampath¹,

Rini²,

Long³

1998

FOC

View full text Add to dashboard Cite

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 the retrosigmoid (suboccipital); 301 (29%) via translabyrinthine; and 16 (2%) via middle fossa approach. Patients undergoing the middle fossa approach were excluded from the study. Patients were subdivided into three groups based on tumor size: Group 1 tumors (609 patients [61%]) were smaller than 2.5 cm; Group 2 tumors (244 patients [24%]) were between 2.5 and 4 cm; and Group 3 tumors (153 patients [15%]) were larger than 4 cm. Operative notes were analyzed for each patient. Relevant cranial nerve and vascular “involvement” as well as anatomical location with respect to the tumor in the CPA were noted. “Involvement” was defined as intimate contact between neurovascular structure and tumor (or capsule), where surgical dissection was required to free the structure. Seventh and eighth cranial nerve involvement was divided into anterior, posterior, and polar (around the upper or lower pole) locations. Anterior and posterior locations were further subdivided into upper, middle, or lower thirds of the tumor. The most common location of the seventh cranial nerve (facial) was the anterior middle third of the tumor for Groups 1, 2, and 3, although a significant number were found on the anterior superior portion. The posterior location was exceedingly rare (< 1%). Interestingly, patients with smaller tumors (Group 1) had an incidence (3.4%) of the seventh cranial nerve passing through the tumor itself equal to that of patients with larger tumors. The most common location of the seventh cranial nerve complex was the anterior inferior portion of the tumor. Not surprisingly, larger tumors (Group 3) had a higher incidence of involvement of sixth cranial nerve (41%), fifth cranial nerve (100%), ninth-11th cranial nerve complex (99%), 12th cranial nerve (31%), as well as superior cerebellar artery (79%), anterior inferior cerebellar artery (AICA) trunk (91.5%), AICA branches (100%), posterior inferior cerebellar artery (PICA) trunk (59.5%), PICA branches (79%), and the vertebral artery (93.5%). A small number of patients in Group 3 also had AICA (3.3%), PICA (3.3%), or vertebral artery (1.3%) vessels within the tumor itself. In this study, the authors show the great variation in anatomical location and involvement of neurovascular structures in the CPA. With this knowledge, they present certain technical lessons that may be useful in preserving function during surgery and, in doing so, hope to provide neurosurgeons and neurootologists with valuable information that may help to achieve optimum cranial nerve outcomes in patients.

show abstract

Hearing conservation in acoustic neuroma surgery via the posterior fossa

Cited by 46 publications

References 16 publications

Hearing Preservation by the Extended and Nonextended Middle Cranial Fossa Approach for Acoustic Neuroma

Hearing Preservation by the Extended and Nonextended Middle Cranial Fossa Approach for Acoustic Neuroma

Surgery for vestibular schwannomas: a systematic review of complications by approach

Microanatomical variations in the cerebellopontine angle associated with vestibular schwannomas (acoustic neuromas)

Contact Info

Product

Resources

About