The study of predictive factors for the evolution of vestibular schwannomas.

PURPOSE: The primary objective was to determine whether the analysis of textural heterogeneity of vestibular schwannomas on MRI at diagnosis was predictive of their radiological evolutivity. The secondary objective was to determine whether some clinical or radiological factors could also be predictive of growth. METHODS: We conducted a pilot, observational and retrospective study of patients with a vestibular schwannoma, initially monitored, between April 2001 and November 2019 within the Oto-Neurosurgical Institute of Champagne Ardenne, Texture analysis was performed on gadolinium injected T1 and CISS T2 MRI sequences and six parameters were extracted: mean greyscale intensity, standard deviation of the greyscale histogram distribution, entropy, mean positive pixels, skewness and kurtosis, which were analysed by the Lasso method, using statistically penalised Cox models. Extrameatal location, tumour necrosis, perceived hearing loss < 2 years with objectified tone audiometry asymmetry, tinnitus at diagnosis, were investigated by the Log-Rank test to obtain univariate survival analyses. RESULTS: 78 patients were included and divided into 2 groups: group A comprising 39 "stable patients", and B comprising the remaining 39 "progressive patients". Independent analysis of the texture factors did not predict the growth potential of vestibular schwannomas. Among the clinical or radiological signs of interest, hearing loss < 2 years was identified as a prognostic factor for tumour progression with a significant trend (p = 0.05). CONCLUSIONS: This study did not identify an association between texture analysis and vestibular schwannomas growth. Decreased hearing in the 2 years prior to diagnosis appears to predict potential radiological progression.

Efficacy and complications of microvascular decompression in patients over 70 years with trigeminal neuralgia.

OBJECTIVE: Treatment of choice for trigeminal neuralgia (TN) by neurovascular conflict in case of failure of medical treatment is microvascular decompression (MVD). It is a safe and effective technique in the short and long term. But what about older patients who are considered more fragile anesthetically and surgically? Our Objective is to demonstrate the efficacy and complication rate of microvascular decompression (MVD) for older and younger patients with trigeminal neuralgia (TN) due to neurovascular conflict. METHODS: 102 patients with TN due to neurovascular conflict were included (June 2005-December 2016) in a single Regional hospital. 25 were included in the group composed of ≥ 70-year-old patients (G1), while 77 were included in the < 70-year-old group (G2). The patients were operated on by the same surgical team using a retro-sigmoid approach to access the neurovascular conflict. The epidemiologic, clinical, anesthetic, and surgical data were extracted. RESULTS: The immediate efficacy of surgical treatment (BNI pain intensity = I) was 96% in G1 and 96.10% in the G2 group (p = 0.71). At 3-year follow-up, the efficacy rate was 89% and 86%, respectively (p = 0.93). At 5 years, it was 92% and 92% (p = 0.98). Complication rates were comparable between the two groups (20% versus 27%; p = 0.47) and no deaths occurred despite the fact that G1 group had worst preoperative anesthetic score (ASA-NYHA). CONCLUSION: MVD is a durable procedure in patients over 70 years of age diagnosed with essential TN. The complication rate and immediate-, medium-, and long-term efficacy were similar to those of younger patients.

Long-term efficacy of vestibular neurotomy in disabling Ménière's disease and Tumarkin drop attacks.

OBJECTIVE: When Ménière's disease (MD) becomes disabling due to the frequency of attacks or the appearance of drop attacks (i.e., Tumarkin otolithic crisis) despite "conservative" medical and surgical treatments, a radical treatment like vestibular neurotomy (VN) is possible. An ideal MD treatment would relieve symptoms immediately and persist after the therapy. The aim of this study was to identify if VN was effective after 10 years of follow-up regarding vertigo and drop attacks, and to collect the immediate complications. METHODS: The authors report a retrospective, single-center (i.e., in a single tertiary referral center with otoneurological surgery activity) cohort study conducted from January 2003 to April 2020. All patients with unilateral disabling MD who had received a VN with at least 10 years of follow-up were included. The therapeutic efficacy was defined by complete disappearance of vertigo and drop attacks. The postoperative complications (CSF leak, total deafness, meningitis, death) were determined immediately after the surgery, and the hearing thresholds were determined during the patient follow-up with the pure tone average (PTA). RESULTS: A total of 74 patients (of 85 who were eligible), average age 51.9 ± 11.1 years, including 38 men (51.4%), with disabling MD and/or Tumarkin drop attacks (24.3%) received VN, with at least 10 years of follow-up after surgery. After an average follow-up of 12.4 ± 1.7 years (range 10.0-16.3 years), 67 patients (90.5%) no longer presented any vertiginous attacks, and no patient experienced drop attack. The mean variation in early pre- and postoperative PTA was not statistically significant (n = 64, 2.2 ± 10.3 decibels hearing level [range -18 to 29], 95% CI [-0.4 to 4.37]; p = 0.096), and 84.4% of the patients evaluated had unchanged or improved postoperative PTA. Three significant complications were noted, including two surgical revisions for CSF leak. There was no permanent facial paralysis, meningitis, or death. CONCLUSIONS: In case of disabling MD (disabling vertigo refractory to conservative vestibular treatments-Tumarkin drop attacks), VN via the retrosigmoid approach must be the prioritized proposal in comparison to intratympanic gentamicin injections, because of the extremely low complication rate and the immediate and long-lasting effect of this treatment on vertigo and falls.

Peristimulus Time Responses Predict Adaptation and Spontaneous Firing of Auditory-Nerve Fibers: From Rodents Data to Humans.

Sound-level coding in the auditory nerve is achieved through the progressive recruitment of auditory nerve fibers (ANFs) that differ in threshold of activation and in the stimulus level at which the spike rate saturates. To investigate the functional state of the ANFs, the electrophysiological tests routinely used in clinics only capture the first action potentials firing in synchrony at the onset of the acoustic stimulation. Assessment of other properties (e.g., spontaneous rate and adaptation time constants) requires single-fiber recordings directly from the nerve, which for ethical reasons is not allowed in humans. By combining neuronal activity measurements at the round window and signal-processing algorithms, we constructed a peristimulus time response (PSTR), with a waveform similar to the peristimulus time histograms (PSTHs) derived from single-fiber recordings in young adult female gerbils. Simultaneous recordings of round-window PSTR and single-fiber PSTH provided models to predict the adaptation kinetics and spontaneous rate of the ANFs tuned at the PSTR probe frequency. The predictive model derived from gerbils was then validated in female mice and finally applied to humans by recording PSTRs from the auditory nerve in normal-hearing patients who underwent cerebellopontine angle surgeries. A rapid adaptation time constant of ∼3 ms and a mean spontaneous rate of ∼22 spikes/s in the 4 kHz frequency range were found. This study offers a promising diagnostic tool to map the human auditory nerve, thus opening new avenues to better understanding auditory neuropathies, tinnitus, and hyperacusis.SIGNIFICANCE STATEMENT Neural adaptation in auditory nerve fibers corresponds to the reduction in the neuronal activity to prolonged or repeated sound stimulation. For obvious ethical reasons, single-fiber recordings from the auditory nerve are not feasible in humans, creating a critical gap in extending data obtained using animal models to humans. Using electrocochleography in rodents, we inferred adaptation kinetics and spontaneous discharge rates of the auditory nerve fibers in humans. Routinely used in basic and clinical laboratories, this tool will provide a better understanding of auditory disorders such as neuropathies, tinnitus, and hyperacusis, and will help to improve hearing-aid fittings.

Efficacy and Complications of Microsurgical Neurovascular Decompression in 55 Patients With Hemifacial Spasm.

OBJECTIVE: To analyze the efficacy and complications of microvascular decompression for hemifacial spasm. STUDY DESIGN: Retrospective study. SETTING: Regional hospital. METHODS: Fifty-five patients with hemifacial spasm were treated by microvascular decompression. All patients with hemifacial spasm who underwent retrosigmoid microvascular decompression from May 2004 to January 2017 were included. Patients with no conflict on preoperative magnetic resonance imaging or with an alternate diagnosis were excluded. RESULTS: The overall cure rate was 83.64%, with an average follow-up of 7.4 years. A left-sided hemifacial spasm was a healing-promoting factor (P = .01). The median healing was 0.03 months, and the mean was 6 months. The efficacy remained high in the medium term (88% at 3 years), long term (90.24% at 5 years), and very long term (90.48% at 8 years). The recurrence rate was 9.8%. Favorable criteria included a right-sided spasm (P = .01) and an average age of 62 years (P = .03). The specific complications were permanent facial palsy (3.63%), unilateral deafness (5.45%), and hearing loss (3.63%). No death was reported. Regarding the quality of life of the patients, 94.7% had a modified HFS-8 postoperative score of 0 (Hemifacial Spasm 8 Quality of Life Scale). CONCLUSION: Microvascular decompression for hemifacial spasm is an effective and lasting technique. Its low rate of complications and the considerable quality-of-life improvement should lead surgeons to propose it to patients as soon as botulinum toxin injections become ineffective or poorly tolerated.

Surgical treatment of high-grade spondylolisthesis: Technique and results.

BACKGROUND: Surgical management of high-grade spondylolisthesis is not only challenging but also controversial, from in situ fusion to complete reduction. We report our results of a safe three-stage spinal procedure in a single surgical session with seven patients diagnosed high-grade spondylolisthesis. HYPOTHESIS: Posterior fixation combined with interbody fusion is effective on reduction, ossification and clinical outcomes in high-grade spondylolisthesis. PATIENTS AND METHODS: This study is a retrospective review of patients who underwent surgery between 2016 and 2018. The surgical method involved specific installation for deformity reduction, pedicle screw fixation, correction of lumbosacral kyphosis with a specific distraction maneuver, wide decompression, gradual reduction of the deformity, and sometimes maintenance of the reduction with interbody fusion. Patients were checked out at 2, 6 and 12 months and yearly after the procedure. Clinical, radiological, Visual Analogic Scale (VAS) and Oswestry Disability Index (ODI) outcomes measures were collected. RESULTS: Seven patients with high-grade spondylolisthesis at L5-S1 (2 patients grade II, 4 patients grade IV and 1 patient grade V), with a median age of 37 years [17; 72] were included. Median follow-up was 24 months [12; 25 months]. All patients have a fused joint at 6 months except one. Median lumbosacral angle (LSA) improved from 76°[59; 85] to 94°[76; 104]. Meyerding grade of 2 cases was stable after surgery, 3 cases with loss of two ranks and 2 cases with loss of one rank. The radiological parameters showed statistically significant difference (p = 0.036) postoperatively. There was not deep infection. Medians VAS and ODI showed improved pain and disability scores. CONCLUSION: This procedure allows correct reduction rate of high-grade spondylolisthesis with good clinic-radiologic outcomes. Though surgically demanding, it was safe and reproducible. LEVEL OF EVIDENCE: IV, retrospective.

Clipping of recanalized intracerebral aneurysms initially treated by the Woven EndoBridge device.

BACKGROUND AND PURPOSE: Intrasaccular flow disruption using the Woven EndoBridge (WEB) is a safe and effective method to treat intracranial aneurysms, particularly wide neck bifurcation aneurysms. However mid term and long term follow-up imaging can show aneurysm remnant or recanalization, and retreatment is therefore sometimes necessary. In most cases, retreatment is performed using an endovascular approach. The present series reports and analyzes aneurysm clipping of recanalized or incompletely occluded aneurysms following WEB treatment. METHODS: All patients treated with the WEB device since the beginning of our experience in June 2011 were prospectively collected in a local database. Among them, patients who were retreated by clipping for aneurysm remnants were included in the present series. RESULTS: In the cumulative population of 130 patients with aneurysms treated by the WEB device from June 2011 to February 2019, 4 patients (3.1%) were retreated with surgical clipping due to incomplete occlusion (2 patients) and aneurysm recanalization (2 patients). Three of the four aneurysms retreated (75%) were located in the middle cerebral artery and one in the anterior communicating artery (25.0%). The aneurysm was ruptured in 1 of 4 patients (25%). Clipping was performed 10-54 months after initial treatment with the WEB. Surgical exposure showed that the WEB device was inside the aneurysm sac in all cases. Clipping was easily performed in all but 1 case. Control DSA showed complete occlusion in two aneurysms and a neck remnant in two. CONCLUSION: Clipping is a feasible option for treating aneurysm remnants following initial treatment with intrasaccular flow disruption using the WEB.

Skeletal involvement of hairy cell leukemia.

Hairy cell leukemia (HCL) is a rare B-cell lymphoproliferative disorder. Skeletal involvement is an unusual manifestation of HCL, complicating the course of the disease in approximately 3% of patients. We describe a case of skull involvement by HCL, a localization rarely reported in the literature.

Transglabellar approach for resection of anterior midline skull base meningiomas: technical note.

BACKGROUND: We describe our experience of minimally invasive approach of the anterior skull base through the transglabellar approach. METHOD: The technical details of the transglabellar approach are described in this article as we have been using it for the past 3 years. After an inter-eyebrow skin incision, the scalp is elevated allowing the creation of a 3-cm bone flap in the frontal sinus, which gives direct access to the anterior midline skull base. Removal of the tumour is carried out without brain retraction. The closure requires obstruction of nasofrontal ducts and sinus mucosa removal. RESULTS: We operated on 24 patients using this approach. The tumour was completely removed in every case. We reported one case of meningitis and three cerebrospinal fluid leaks. Every patient was satisfied with the aesthetic results. CONCLUSIONS: The transglabellar approach is a reasonably easy and efficient way to resect anterior midline skull base meningiomas.