Pierre Roche

HEARING PRESERVATION AFTER GAMMA KNIFE RADIOSURGERY FOR VESTIBULAR SCHWANNOMAS PRESENTING WITH HIGH-LEVEL HEARING

OBJECTIVEThe aim of this study was to evaluate long-term hearing preservation after gamma knife radiosurgery (GKS) for vestibular schwannomas in patients with initially normal or subnormal hearing (Gardner-Robertson Class 1) and to determine the predictive factors for functional hearing preservation. METHODSSince July 1992, more than 2053 vestibular schwannomas have been treated by GKS and followed at the Timone University Hospital, Marseille. A minimum of 3 years of follow-up (range, 3–11 years; median, 48 months) is available for 74 patients (without neurofibromatosis Type 2 or previous surgery) with Gardner-Robertson Class 1 hearing. RESULTSThe average age of the patients was 47.5 years (range, 17–76 years). The number of tumors in Koos Stage I was 8, the average number in Stage II was 21, the average number in Stage III was 43, and the average number in Stage IV was 2. The median number of isocenters was 8 (range, 2–45), and the median marginal dose was 12 Gy (range, 9–13 Gy). At the time of the last follow-up evaluation, 78.4% of the patients had preserved functional hearing. Tumor control was achieved in 93% of the cases. The probability of preserving functional hearing was higher in patients who had an initial symptom other than hearing decrease (91.1%), in patients younger than 50 years (83.7%), and in those treated with a dose to the cochlea of less than 4 Gy (90.9%). CONCLUSIONThis study shows that the probability of preserving functional hearing in the long term after GKS for patients presenting with unilateral vestibular schwannomas is very high. The positive predictive factors appear to be young age, an initial symptom other than hearing decrease, and a low dose to the cochlea.

Gamma knife surgery for facial nerve schwannomas

OBJECTIVERadical resection of facial nerve schwannomas classically implies a high risk of severe facial palsy. Owing to the rarity of facial palsy after gamma knife surgery (GKS) of vestibular schwannomas, functional evaluation after GKS seems rational in this specific group of patients. To our knowledge, no previous similar evaluation exists in the literature. METHODSOf 1783 schwannomas of the cerebellopontine angles treated by GKS at Timone University Hospital between July 1992 and May 2003, 11 were diagnosed as originating from the facial nerve. Criteria for this diagnosis were the involvement of the tympanic or mastoid segment of the facial nerve (n = 9) and/or preoperative observation of a facial nerve deficit that had occurred during previous microsurgery (two patients). The rare occurrence of facial palsy after vestibular schwannoma radiosurgery, usually within 18 months of treatment, has been considered only in the patients with more than 2 years of follow-up (n = 9). RESULTSSix of these patients experienced a previous spontaneous facial palsy on one (n = 4) or several occasions (n = 2). A normal motor facial function was observed in only three patients before GKS (House-Brackmann Grade II in six patients, Grade III in one patient, Grade IV in one patient). The median follow-up period was 39 months (range, 18–84 mo). At the time of the last follow-up examination, no patients had developed a new facial palsy or experienced deterioration of a preexisting facial palsy and three patients had improvement of a preoperative facial palsy. Ten out of the 11 tumors are stable or decreased in size; in the other, a microsurgical resection of the tumor had been recommended owing to the development of a cyst. Clinical management owing to the specificity and heterogeneity of this group of patients has required the development of an original classification of four anatomic subtypes presenting different clinical and surgical difficulties. CONCLUSIONThis first study demonstrates that radiosurgery allows treatment of these patients while preserving normal motor facial function. Such an advantage should lead to the consideration of GKS as a first treatment option for small- to medium-size facial nerve schwannomas.

Wait-and-see strategy compared with proactive Gamma Knife surgery in patients with intracanalicular vestibular schwannomas

OBJECT The roles of the wait-and-see strategy and proactive Gamma Knife surgery (GKS) in the treatment paradigm for small intracanalicular vestibular schwannomas (VSs) is still a matter of debate, especially when patients present with functional hearing. The authors compare these 2 methods. METHODS Forty-seven patients (22 men and 25 women) harboring an intracanalicular VS were followed prospectively. The mean age of the patients at the time of inclusion was 54.4 years (range 20-71 years). The mean follow-up period was 43.8 ± 40 months (range 9-222 months). Failure was defined as significant tumor growth and/or hearing deterioration that required microsurgical or radiosurgical treatment. This population was compared with a control group of 34 patients harboring a unilateral intracanalicular VS who were consecutively treated by GKS and had functional hearing at the time of radiosurgery. RESULTS Of the 47 patients in the wait-and-see group, treatment failure (tumor growth requiring treatment) was observed in 35 patients (74%), although conservative treatment is still ongoing for 12 patients. Treatment failure in the control (GKS) group occurred in only 1 (3%) of 34 patients. In the wait-and-see group, there was no change in tumor size in 10 patients (21%), tumor growth in 36 patients (77%), and a mild decrease in tumor size in 1 patient (2%). Forty patients in the wait-and-see group were available for a hearing level study, which demonstrated no change in Gardner-Robertson hearing class for 24 patients (60%). Fifteen patients (38%) experienced more than 10 db of hearing loss and 2 of them became deaf. At 3, 4, and 5 years, the useful hearing preservation rates were 75%, 52%, and 41% in the wait-and-see group and 77%, 70%, and 64% in the control group, respectively. Thus, the chances of maintaining functional hearing and avoiding further intervention were much higher in cases treated by GKS (79% and 60% at 2 and 5 years, respectively) than in cases managed by the wait-and-see strategy (43% and 14% at 2 and 5 years, respectively). CONCLUSIONS These data indicate that the wait-and-see policy exposes the patient to elevated risks of tumor growth and degradation of hearing. Both events may occur independently in the mid-term period. This information must be presented to the patient. A careful sequential follow-up may be adopted when the wait-and-see strategy is chosen, but proactive GKS is recommended when hearing is still useful at the time of diagnosis. This recommendation may be a main paradigm shift in the practice of treating intracanalicular VSs.

Hearing preservation in patients with unilateral vestibular schwannoma after gamma knife surgery

INTRODUCTION The majority of patients still lose the functionality of their hearing in spite of the technical advances in microsurgery. Our aim was to evaluate the hearing preservation potential of Gamma Knife Surgery. We have reviewed our experience and the literature in order to evaluate the probability to obtain such functional preservation and the factors influencing it. METHODS Since July 1992, 2,053 patients have been operated on by Gamma Knife Radiosurgery in Timone University Hospital. This population included 184 unilateral schwannoma patients with functional preoperative hearing (Gardner-Robertson 1 or 2) treated by first intention radiosurgery with a marginal dose lower than 13 Gy. The population included 74 patients with subnormal hearing (class 1). All have been studied with a follow-up longer than 3 years. Univariate and multivariate analyses have been carried out. RESULTS Numerous parameters greatly influence the probability of functional hearing preservation at 3 years, which is globally 60%. The main preoperative parameters of predictability are limited hearing loss that is Gardner-Robertson stage 1 (vs. 2), presence of tinnitus, young age of the patient and small size of the lesion. The functional hearing preservation at 3 years is 77.8% when the patient is initially in stage 1, 80% in patients with tinnitus as a first symptom and 95% when the patient has both. In these patients, the probability of functional preservation at 5 years is 84%. Comparison of these results with the main series of the literature confirms the reproducibility of our results. Additionally, we have demonstrated a higher chance of hearing preservation when the dose to the cochlea is lower than 4 Gy. CONCLUSION We report a large population of patients treated by radiosurgery with functional preoperative hearing. These results demonstrate the possibility to preserve functional hearing in a high percentage of selected patients. Radiosurgery offers them a higher chance of functional hearing preservation than microsurgery or simple follow-up.

Long-term outcome in intensive care unit survivors after mechanical ventilation for intracerebral hemorrhage.

ObjectiveTo evaluate long-term survival and functional outcome in intensive care unit survivors after mechanical ventilation for intracerebral hemorrhage. DesignRetrospective chart review and prospective follow-up study. SettingOutpatient follow-up. PatientsBetween 1997 and 2000, 120 patients were mechanically ventilated for an intracerebral hemorrhage at our intensive care unit. Sixty-two patients were discharged from hospital (in-hospital mortality = 48%). Sixty patients were evaluated for survival and functional outcome (two were lost to follow-up). Time between discharge and follow-up was ≥1 yr and was a mean of 27 ± 14 months (range, 12–56). InterventionsNone. Measurements and Main ResultsPatients’ physicians were first asked about survival, and patients or proxies were interviewed by phone. Barthel Index and modified Rankin Scale scores were collected, and demographic information and general data were reviewed. The estimated life-table survival curve after discharge was 64.6% at 1 yr and 57% at 3 yrs. In the 24 patients who died, the mean time between discharge and death was 5 ± 6 months. Probability of death after discharge significantly increased if age at admission was >65 yrs (p < .01; odds ratio, 3.5; 95% confidence interval, 1.4–9.1) and if Glasgow Coma Scale score at discharge was <15 (p < .01; odds ratio, 3.9; 95% confidence interval, 1.6–9.5). In the 36 long-term survivors, Barthel Index was 67.5 ± 15 (median ± median absolute dispersion) and modified Rankin Scale score was 2.6 ± 0.5. Fifteen patients (42%) had a slight or no disability (Barthel Index ≥90 and modified Rankin Scale score ≤2), whereas 21 patients (58%) had moderate or severe disability (Barthel Index ≤85 and modified Rankin Scale score >2). ConclusionsProbability of survival at 3 yrs after mechanical ventilation for an intracerebral hemorrhage was >50%. Age was an important determinant of long-term survival. Forty-two percent of long-term survivors were independent for activities of daily living. Only a few long-term survivors had a very high degree of disability.

Gamma knife surgery for facial nerve schwannomas.

Radical resection of facial nerve schwannomas classically implies a high risk of severe facial palsy. Due to the rarity of facial palsy following Gamma Knife surgery (GKS) of vestibular schwannomas, functional evaluation after GKS in this specific group of patient appears rational. Clinical management due to the specificity and heterogeneity of this group of patients has required the development of an original classification of 4 anatomical subtypes presenting different clinical and surgical difficulties. Among 1,783 schwannomas of the cerebellopontine angle treated by GKS in Timone University Hospital between July 1992 and May 2003, 11 were diagnosed as originating from the facial nerve. Criteria for this diagnosis were: the involvement of the tympanic or mastoid segment of the facial nerve (9 patients); and/or preoperative observation of a facial nerve deficit that had occurred during previous microsurgery (2 patients). The rare occurrence of facial palsy after vestibular schwannoma radiosurgery, usually occurring within 18 months of treatment, has been considered only in the patients with more than 2 years of follow-up (9 patients). At last follow-up examination, no patients had developed a new facial palsy or experienced deterioration of a pre-existing facial palsy; 3 patients had improvement of a preoperative facial palsy. Ten of 11 tumors were stable, or decreased in size; in the remaining case, microsurgical resection of the tumor had been recommended due to the development of a cyst. This first study demonstrates that radiosurgery allows treatment of these patients while preserving normal motor facial function. Such an advantage should lead to the consideration of GKS as a first treatment option for small- to middle-sized facial nerve schwannomas.

La pétrectomie combinée Bases anatomiques, technique chirurgicale et indications

Management of large petroclival tumors requires the use of extensive surgical approaches that usually jeopardize the intrapetrous neuro-otologic structures. To confirm the interest of the combined petrosal approach in this indication, we describe the relevant anatomy and the surgical steps of this procedure. After making a periauricular skin incision and muscle elevation, an occipitotemporal bone flap is shaped. Then a retrolabyrinthine exposure is undertaken, with optimal skeletonization of the semicircular canals. Around the internal auditory canal, the retromeatal area and the petrous apex are resected. The retrosigmoid dura is opened followed by the incision of the subtemporal and posterior fossa dura along the superior petrosal sinus. The sinus is coagulated and divided. The tentorium is sectioned transversally toward its free edge behind the porus of the trochlear nerve. The combined petrosal approach is able to provide a wide multidirectional corridor toward the ventral surface of the pons, the basilary trunk and the ipislateral cranial nerves from the oculomotor to the lower cranial nerves. This study confirms that despite a significant extra time needed for proper achievement, the combined petrosal approach is a valuable conservative approach when the petroclival area, ventral brain stem and basilary trunk are targeted. This approach should be included in the panel of the transpetrous routes available by expert skull base teams.

[The combined petrosal approach. Anatomical principles, surgical technique and indications].

Management of large petroclival tumors requires the use of extensive surgical approaches that usually jeopardize the intrapetrous neuro-otologic structures. To confirm the interest of the combined petrosal approach in this indication, we describe the relevant anatomy and the surgical steps of this procedure. After making a periauricular skin incision and muscle elevation, an occipitotemporal bone flap is shaped. Then a retrolabyrinthine exposure is undertaken, with optimal skeletonization of the semicircular canals. Around the internal auditory canal, the retromeatal area and the petrous apex are resected. The retrosigmoid dura is opened followed by the incision of the subtemporal and posterior fossa dura along the superior petrosal sinus. The sinus is coagulated and divided. The tentorium is sectioned transversally toward its free edge behind the porus of the trochlear nerve. The combined petrosal approach is able to provide a wide multidirectional corridor toward the ventral surface of the pons, the basilary trunk and the ipislateral cranial nerves from the oculomotor to the lower cranial nerves. This study confirms that despite a significant extra time needed for proper achievement, the combined petrosal approach is a valuable conservative approach when the petroclival area, ventral brain stem and basilary trunk are targeted. This approach should be included in the panel of the transpetrous routes available by expert skull base teams.

La pétrectomie combinée

Management of large petroclival tumors requires the use of extensive surgical approaches that usually jeopardize the intrapetrous neuro-otologic structures. To confirm the interest of the combined petrosal approach in this indication, we describe the relevant anatomy and the surgical steps of this procedure. After making a periauricular skin incision and muscle elevation, an occipitotemporal bone flap is shaped. Then a retrolabyrinthine exposure is undertaken, with optimal skeletonization of the semicircular canals. Around the internal auditory canal, the retromeatal area and the petrous apex are resected. The retrosigmoid dura is opened followed by the incision of the subtemporal and posterior fossa dura along the superior petrosal sinus. The sinus is coagulated and divided. The tentorium is sectioned transversally toward its free edge behind the porus of the trochlear nerve. The combined petrosal approach is able to provide a wide multidirectional corridor toward the ventral surface of the pons, the basilary trunk and the ipislateral cranial nerves from the oculomotor to the lower cranial nerves. This study confirms that despite a significant extra time needed for proper achievement, the combined petrosal approach is a valuable conservative approach when the petroclival area, ventral brain stem and basilary trunk are targeted. This approach should be included in the panel of the transpetrous routes available by expert skull base teams.

A randomized controlled study assessing outcome, cognition, autonomy and quality of life in over 70-year-old patients after aneurysmal subarachnoid hemorrhage

BACKGROUND Current aging of the population with good physiological status and the increasing incidence of subarachnoid hemorrhage (SAH) in elderly patients has enhanced the benefit of treatment in terms of independence and long-term quality of life (QoL). METHODS From November 1, 2008 to October 30, 2012, 351 patients aged 70 years or older with aneurysmal SAH underwent adapted treatment: endovascular coiling (EV) for 228 (65%) patients, microsurgical clipping (MS) for 75 (29.3%) or conservative treatment for 48 (13.7%). Forty-one of these were randomized to EV (n=20) or to MS (n=21). The objectives were to determine the proportion of patients with modified Rankin Scale score≤2 (independence) at 1 year, and, secondarily, to compare cognitive function on the Mini-Mental State Examination (MMSE), autonomy on the Activities of Daily Living Index (ADLI) and Instrumental Activities of Daily Living scale (IADL), and QoL, in the prospective and randomized arms, at 1 year. RESULTS At 1 year, with 1 loss to follow-up in the EV arm, 11 patients (55%) were independent after EV occlusion and 8 (38.1%) after MS exclusion, without significant difference (P=0.29). Mortality was higher after MS during the first 2 postoperative months, and thereafter the difference between MS and EV ceased to be significant. Cognitive function and autonomy scores were similar in both arms. CONCLUSION In elderly patients treated for aneurysmal SAH, approximately 50% were independent at 1 year, with conserved cognition and autonomy. EV and MS are valid procedures in this population, with similar results at 1 year in terms of independence, cognition, autonomy, and QoL.