Posts Tagged ‘acoustic neuroma’
Background: Cochlear dose has been identified as a potentially modifiable contributor to hearing loss following stereotactic radiosurgery (SRS) for vestibular schwannoma (VS).
Objective: (1) to evaluate the association between CT-based volumetric cochlea dose and loss of serviceable hearing following SRS; 2) to assess intra- and interobserver reliability when determining modiolar point dose using MRI and CT; 3) and to discuss the clinical significance of the cochlea dose with regard to radiosurgical planning strategy.
Methods: Patients with serviceable pre-treatment hearing who underwent SRS for sporadic VS between using Gamma Knife Perfexion were studied. Univariate and multivariate associations with the primary outcome of time to non-serviceable hearing were evaluated.
Background: Management of neurofibromatosis type 2 (NF2)—associated vestibular schwannomas (VSs) remains controversial. Stereotactic radiosurgery (SRS) with conventional dosing is less effective for NF2-related VS compared with sporadic lesions.
Objective: To evaluate optimal SRS dose parameters for NF2-related VS and to report long-term outcomes.
Methods: A prospective database was reviewed and outcome measures, including radiographic progression, American Academy of Otolaryngology—Head and Neck Surgery hearing class, and facial nerve function, were analyzed. Progression-free survival was estimated with Kaplan-Meier methods. Associations between tumor progression and radiosurgical treatment parameters, tumor volume, and patient age were explored with the use of Cox proportional hazards regression.
Background: Fractionated Stereotactic Radiotherapy (FSRT) is a non-invasive treatment for acoustic neuromas (AN). Initial reports from our institution demonstrated that reduction of treatment dose to 46.8 Gy resulted in improved preservation of functional hearing status.
Objective: We now report the tumor control (TC), symptomatic outcome, and hearing preservation rate (HP) in patients treated with reduced-dose FSRT.
Methods: We analyzed all patients with AN treated from 2002 to 2011. All patients received 46.8 Gy in 1.8 Gy fractions. Follow-up audiogram and MRI were performed in = one-year intervals. TC and HP were calculated by the Kaplan-Meier method. Analysis of HP, defined as Gardner-Robertson value = 2, was determined by audiometric data. Non-hearing related symptoms were defined by Common Terminology Criteria for Adverse Events version 4.
Background: Radiosurgery is increasingly used to treat vestibular schwannomas (VSs). Increasing the sensitivity of VS cells to irradiation (IR) could allow for lower and/or more effective doses of IR, improving safety and efficacy. Persistent c-Jun N-terminal kinase (JNK) activity in VS cells reduces cell death by suppressing accumulation of reactive oxygen species (ROS), raising the possibility that JNK activity protects against IR-induced VS cell death, which is mediated by ROS.
Objective: To determine the extent to which JNK signaling contributes to VS cell radiosensitivity.
Methods: Primary human VS cultures, derived from acutely resected tumors, received single doses (5-40 Gy) of [gamma]-irradiation. Histone 2AX phosphorylation, a marker of IR-induced DNA damage, was assayed by western blot and immunostaining. ROS levels were quantified by measuring 2′,7′-dichlorodihydrofluorescein diacetate (CM-H2DCFDA) fluorescence. Cell apoptosis was determined by terminal deoxynucleotidyl transferase dUTP nick end labeling.
Background: Despite advanced microsurgical techniques, more refined instrumentation, and expert team management, there is still a significant incidence of complications in vestibular schwannoma surgery.
Objective: To analyze complications from the microsurgical treatment of vestibular schwannoma by an expert surgical team and to propose strategies for minimizing such complications.
Methods: Surgical outcomes and complications were evaluated in a consecutive series of 410 unilateral vestibular schwannomas treated from 2000 to 2009. Clinical status and complications were assessed postoperatively (within 7 days) and at the time of follow-up (range, 1-116 months; mean, 32.7 months).
Background: Despite advanced microsurgical techniques, more refined instrumentation, and expert team management, there is still a significant incidence of complications in vestibular schwannoma (VS) surgery.
Objective: To analyze complications from the microsurgical treatment of VS by an expert surgical team and to propose strategies for minimizing such complications.
Methods: Surgical outcomes and complications were evaluated in a consecutive series of 410 unilateral VSs treated from 2000 to 2009. Clinical status and complications were assessed postoperatively (within 7 days) and at the time of follow-up (range: 1 to 116 months; mean: 32.7 months).
Background: Permanent facial nerve (FN) paresis after vestibular schwannoma surgery is distressing to both the patient and surgeon. Intraoperative electrophysiological testing has proven invaluable in reducing the incidence of FN injury and may assist in prognosticating long-term function.
Objective: To report definitive FN outcomes among a cohort of patients with an unevokable but anatomically intact seventh nerve after microsurgical vestibular schwannoma resection.
Methods: All patients undergoing vestibular schwannoma surgery between 2000 and 2010 at a single tertiary academic referral center were identified. Intraoperative FN monitoring data and definitive FN outcomes were reviewed, and all patients with an anatomically intact but electrically unresponsive FN were included.