A minimally invasive endoscope assisted retrosigmoid approach for removal of arachnoid cysts in the internal auditory canal: a step by step description / Abordagem retrosigmoide minimamente invasiva assistida por endoscopia para remoção de cistos aracnóides no conduto auditivo interno: descrição passo a passo

Abstract Introduction: Arachnoid cyst in the internal auditory canal is a quite rare pathology but due to its compressive action on the nerves in this district should be surgically removed. Several surgical techniques have been proposed but no surgeons have used the minimally assisted endoscope retrosigmoid approach for its removal. Objective: To investigate the feasibility of using a minimally invasive endoscope assisted retro-sigmoid approach for surgical removal of arachnoid cysts in the internal auditory canal. Methods: Minimally invasive endoscope assisted retrosigmoid approach allows to access to the internal auditory canal through a minimally invasive retrosigmoid approach that combines the use of a microscope and an endoscope. It is performed in six steps: soft tissue step, bone step, dura step, cerebellopontine angle step (performed using an endoscope and a microscope), microscope-endoscope assisted arachnoid cysts removal and closure. We tested minimally invasive endoscope assisted retrosigmoid approach for removal of arachnoid cysts in the internal auditory canal on two human cadaveric heads (specimens) of subjects affected from audio-vestibular disorders and with arachnoid cysts in the internal auditory canal confirmed by magnetic resonance imaging. Results: The mass was completely and successfully removed from the two specimens with no damage to the nerves and/or vessels in the surgical area. Conclusion: The results of our study are encouraging and support the feasibility of using minimally invasive endoscope assisted retrosigmoid approach for removal of arachnoid cysts in the internal auditory canal. While further clinical in-vivo studies are needed to confirm the accuracy and safety of using the minimally invasive endoscope assisted retrosigmoid approach for this specific surgery, our group has successfully used the minimally invasive endoscope assisted retrosigmoid approach in the treatment of microvascular compressive syndrome, schwannoma removal and vestibular nerve resection.

Resumo Introdução: O cisto aracnóide no conduto auditivo interno é uma doença bastante rara, mas, devido à sua ação compressiva sobre os nervos deste local, ele deve ser removido cirurgicamente. Várias técnicas cirúrgicas foram propostas, mas ninguém utilizou a abordagem retrosigmoide minimamente invasiva assistida por endoscopia para a sua remoção. Objetivo: Investigar a viabilidade do uso da abordagem retrosigmoide minimamente invasiva assistida por endoscopia para remoção cirúrgica de cistos aracnóides no conduto auditivo interno. Método: A abordagem retrosigmoide minimamente invasiva assistida por endoscopia permite o acesso ao conduto auditivo interno através de uma abordagem retrosigmóide minimamente invasiva que combina o uso de um microscópio e um endoscópio. É realizada em seis etapas: do tecido mole, óssea, dura-máter, do ângulo pontocerebelar (realizado com um endoscópio e um microscópio), remoção e fechamento assistidos por endoscópio-microscópico. Testamos a abordagem retrosigmoide minimamente invasiva assistida por endoscopia para remoção de cistos aracnóides no conduto auditivo interno em duas cabeças de cadáveres humanos (espécimes) de indivíduos afetados por distúrbios auditivos-vestibulares e com cistos aracnóides no conduto auditivo interno confirmado por imagem de ressonância magnética. Resultados: A lesão foi removida completamente e com sucesso nos dois espécimes sem dano aos nervos e/ou vasos na área cirúrgica. Conclusão: Os resultados do nosso estudo são encorajadores e apoiam a viabilidade do uso da abordagem retrosigmoide minimamente invasiva assistida por endoscopia para remoção de cistos aracnóides no conduto auditivo interno. Embora mais estudos clínicos in vivo sejam necessários para confirmar a precisão e a segurança do uso da abordagem retrosigmoide minimamente invasiva assistida por endoscopia para essa cirurgia específica, nosso grupo utilizou com sucesso a abordagem retrosigmoide minimamente invasiva assistida por endoscopia no tratamento da síndrome compressiva microvascular, remoção de schwannoma e ressecção do nervo vestibular.

Removal of Koos IV acoustic neuroma and auditory brainstem implant in NF2 patient.

The authors present the case of removal of a Koos grade IV right acoustic neuroma in a neurofibromatosis type 2 (NF2) patient, already operated on for left cerebellopontine angle meningioma at 7 years of age and a left acoustic neuroma at 16 years of age. A transpetrosal approach allowed cochlear sensor implantation to detect residual hearing. An enlarged retrosigmoid approach then allowed subtotal microsurgical removal of the lesion; consequently, the authors illustrate the technical nuances of an auditory brainstem implant (ABI). One month after surgery, the ABI was successfully switched on, giving back hearing perception to the patient. The video can be found here: https://stream.cadmore.media/r10.3171/2021.7.FOCVID2188.

Spiral Ganglions and Speech Perception in the Elderly. Which Turn of the Cochlea is the More Relevant? A Preliminary Study on Human Temporal Bones.

OBJECTIVES: To identify the cochlear segment in which spiral ganglion neuron (SGN) loss may more severely impact discrimination thresholds. MATERIALS AND METHODS: Thirteen temporal bones from 13 subjects between 55 and 77 years of age were analyzed. The organ of corti was analyzed to identify the loss of hair cells, and the number of SGNs in each cochlear segment were counted. The results of the speech perception test (SPT) and pure tone audiometry (PTA) tests were collected. PTA averages for low and high frequencies were calculated. One-way analysis of variance (ANOVA), Pearson, Spearman, and multilinear regression tests were performed. RESULTS: No statistically significant correlation was identified between the patient's age and number of SGNs. Statistically significant differences were observed between the number of SGNs in the different cochlear segments (one-way ANOVA: p<0.0001) and between poor PTA average and SPT scores (negative correlation) (p=0.03). A statistically significant correlation was identified between the overall number of cochlear SGNs and SPT scores (p=0.02) and between the number of SGNs in cochlear segments I (p=0.04) and II and the SPT score (p=0.03). CONCLUSIONS: We identified that residual SGNs in the basal and middle turns of the cochlea might be determinants of speech perception.

Sensorineural Hearing Loss in Newborns Hospitalized in Neonatal Intensive Care Unit: An Observational Study.

Children hospitalized in Neonatal Intensive Care Units (NICU) present an increased risk for Sensorineural Hearing Loss (SNHL) due to prematurity, hypoxia-ischemia, hyperventilation, low birth weight and the use of ototoxic drugs. The aim of this study was to assess the prevalence of SNHL in newborns hospitalized in a NICU using Transient Evoked Otoacoustic Emissions (TEOAE) and Automated Auditory Brainstem Responses (A-ABR) and analyze the associated risk factors. A sample of 153 newborns hospitalized in NICU underwent TEOAE, A-ABR and clinical ABR to evaluate the presence of hearing deficits. Prevalence of SNHL was calculated and odds ratio for specific risk factors was measured. One-hundred fifteen babies (86.7%) presented normal hearing at TEOAE and A-ABR. Fifteen children had a REFER response at TEOAE and a PASS response at A-ABR. Twenty-five children (16.3%) had a REFER A-ABR and were addressed to clinical ABR. A diagnosis of SNHL was made in 12 (7.8%) newborns. An increased risk of SNHL was observed in preterm children <28 weeks (p=0.0135), in children with neurological disorders (p=0.02), that underwent surgery (p=0.0002), affected from premature retinopathy (p=0.0006), craniofacial malformation (p=0.007) and that had sepsis (p=0.04). Additional risk factors for SNHL in our sample were a maternal disease during pregnancy (p=0.0011), cesarean delivery (p<0.0001) and a twin pregnancy (p<0.0001). SNHL in newborns is correlated with hospitalization in NICU. An accurate hearing screening associated to a rigorous clinical medical collection of data is necessary to promptly identify cases of SNHL in children with a special attention to those hospitalized in NICU and plan proper intervention.

Endoscope-assisted retrosigmoid approach in hemifacial spasm: our experience / Abordagem retrosigmóidea assistida por endoscopia em espasmo hemifacial: nossa experiência

Abstract Introduction: The use of surgical decompression of facial hemispasm due to the loop in the internal auditory canal is not always accepted due to the risk related to the surgical procedure. Currently a new surgical technique allows surgeons to work in safer conditions. Objective: To report the results with endoscope-assisted retrosigmoid approach for facial nerve microvascular decompression in hemifacial spasm due to neurovascular conflict. The surgical technique is described. Methods: We carried out a prospective study in a tertiary referral center observing 12 (5 male, 7 female) patients, mean age 57.5 years (range 49-71) affected by hemifacial spasm, that underwent to an endoscope assisted retrosigmoid approach for microvascular decompression. We evaluated intra-operative findings, postoperative HFS resolution and complication rates. Results: Hemifacial spasm resolution was noticed in 9/12 (75%) cases within 24 h after surgery and in 12/12 (100%) subjects within 45 days. A significant (p < 0.001) correlation between preoperative historical duration of hemifacial spasm and postoperative recovery timing was recorded. Only 1 patient had a complication (meningitis), which resolved after intravenous antibiotics with no sequelae. No cases of cerebrospinal fluid leak, facial palsy or hearing impairment were recorded. Hemifacial spasm recurrence was noticed in the only subject where the neurovascular conflict was due to a vein within the internal auditory canal. Conclusions: The endoscope assisted retrosigmoid approach technique offers an optimal visualization of the neurovascular conflict thorough a minimally invasive approach, thus allowing an accurate decompression of the facial nerve with low complication rates. Due to the less invasive nature, the procedure should be considered in functional surgery of the cerebellar pontine angle as hemifacial spasm treatment, specially when the procedure is performed by an otolaryngologist.

Resumo Introdução: O uso de descompressão cirúrgica do espasmo hemifacial devido ao loop no canal auditivo interno nem sempre é aceito devido ao risco relacionado ao procedimento cirúrgico. Atualmente, uma nova técnica cirúrgica permite trabalhar em condições seguras. Objetivo: Relatar os resultados que obtivemos com a abordagem retrosigmóidea assistida por endoscopia para a descompressão microvascular do nervo facial em casos de espasmo hemifacial devido a conflito neurovascular. A técnica cirúrgica é descrita. Método: Realizamos um estudo prospectivo em um centro de referência terciária observando 12 pacientes (5M, 7F), com média de idade de 57,5 (intervalo 49-71) anos com espasmo hemifacial submetidos a uma abordagem retrosigmóide assistida por endoscopia para descompressão microvascular. Foram avaliados os achados intraoperatórios, a resolução pós-operatória do espasmo hemifacial e as taxas de complicações. Resultados: A resolução do espasmo hemifacial foi observada em 9/12 (75%) dos casos nas 24 horas após a cirurgia e em 12/12 (100%) dos indivíduos até 45 dias. Uma correlação significativa (p < 0,001) entre a duração do histórico pré-operatório de espasmo hemifacial e o tempo de recuperação pós-operatório foi registrado. Apenas um paciente apresentou uma complicação (meningite), que foi resolvida após administração de antibióticos por via intravenosa sem sequelas. Nenhum caso fístula liquórica, paralisia facial ou deficiência auditiva foi registrado. A recorrência do espasmo hemifacial foi observada em único indivíduo em quem o conflito neurovascular foi causado por um vaso no interior do canal auditivo interno. Conclusões: A técnica da abordagem retrosigmóidea assistida por endoscopia oferece uma ótima visualização do conflito neurovascular através de uma abordagem minimamente invasiva, permite assim uma descompressão precisa do nervo facial com baixas taxas de complicações. Por ser menos invasivo, o procedimento deve ser considerado na cirurgia funcional do ângulo pontocerebelar como tratamento de espasmo hemifacial, especialmente quando o procedimento é feito por um otorrinolaringologista.

Evaluation of pediatric cochlear implant care throughout Europe: Is European pediatric cochlear implant care performed according to guidelines?

OBJECTIVES: International guidelines indicate that children with profound hearing loss should receive a cochlear implant (CI) soon after diagnosis in order to optimize speech and language rehabilitation. Although prompt rehabilitation is encouraged by current guidelines, delays in cochlear implantation are still present. This study investigated whether European countries establish timely pediatric CI care based on epidemiological, commercial, and clinical data. METHODS: An estimation of the number of pediatric CI candidates in European countries was performed and compared to epidemiological (Euro-CIU), commercial (Cochlear®), and clinical (institutional) age-at-implantation data. The ages at implantation of pediatric patients in eight countries (the Netherlands, Belgium, Germany, the United Kingdom, France, Turkey, Portugal, and Italy) between 2005 and 2015 were evaluated. RESULTS: From 2010 onwards, over 30% of the pediatric CI candidates were implanted before 24 months of age. Northern European institutions implanted children on average around 12 months of age, whereas southern European institutions implanted children after 18 months of age. The Netherlands and Germany implanted earliest (between 6 and 11 months). DISCUSSION: Implemented newborn hearing screening programs and reimbursement rates of CIs vary greatly within Europe due to local, social, financial, and political differences. However, internationally accepted recommendations are applicable to this heterogeneous European CI practice. Although consensus on early pediatric cochlear implantation exists, this study identified marked delays in European care. CONCLUSION: Regardless of the great heterogeneity in European practice, reasons for latency should be identified on a national level and possibilities to prevent avoidable future implantation delays should be explored to provide national recommendations.

Comparative Study between the use of Melatonin and A Solution with Melatonin, Tryptophan, and Vitamin B6 as an Inducer of Spontaneous Sleep in Children During an Auditory Response Test: An Alternative to Commonly Used Sedative Drugs.

OBJECTIVE: An elective investigation into the early diagnosis of deafness in children under the age of 4-5 years is performed using auditory evoked potentials of auditory brainstem responses (ABRs). In case of pediatric patients, the major difficulty includes being examined during spontaneous sleep, which is complicated to obtain, especially in the age range of 12 to 72 months. Recently, melatonin has been used as a "sleep inducer" in diagnostic tests with positive results. Our aim was to evaluate the use of melatonin and of a solution containing melatonin, tryptophan, and vitamin B6 as an inducer of spontaneous sleep on repeated ABR analyses as well as to evaluate the reduction in analyses with sedative drugs in case of uncooperative patients. MATERIALS AND METHODS: In total, 748 children aged between 12 and 48 months were included in the study and divided into three groups: A: placebo (n=235), B: melatonin (n=246), and C: melatonin, tryptophan, and vitamin B6 (n=267). RESULTS: In groups B and C, in addition to physiological awakening, we observed a significant reduction in the number of repeated analyses as well as drug regimen usage. CONCLUSION: This study confirms the strategic role of melatonin as an inducer of spontaneous sleep. However, above all, it suggests that the administration of a solution containing melatonin, tryptophan, and vitamin B6 significantly reduces the number of repeated ABR examinations as well as the percentage of repeated analysis performed using sedative drugs compared to both the control group and the melatonin-only group.

Bone-anchored hearing aids (Baha) in congenital aural atresia: personal experience.

AIMS: Aural atresia is a congenital disease constituted by partial or complete lack of development of the external auditory canal, which is generally associated with malformations of the auricle and middle ear. Reconstruction of the auditory canal and correction of any deformities of the middle ear have yielded unpredictable results and variable functional outcomes, and there is a high rate of complications. Therefore, the use of bone-conduction hearing aids, such as the Baha, may represent a valid alternative for subjects who have conductive hearing loss with cochlear reserve that, as a rule, is fully conserved. The aim of this work is to reexamine our experience with the management of conductive and mixed hearing loss using the Baha system in children with bilateral aural atresia. METHODS: We examined 31 patients with bilateral congenital aural atresia in whom a Baha system had been implanted. The patients, 16 males and 15 females, were between 5 and 14 years of age (mean 8.7). The following parameters were assessed for each patient: mean preoperative air and bone conduction for frequencies between 0.5 and 4kHz; mean preoperative threshold with conventional bone-conduction hearing aids; mean postoperative threshold with the Baha system; improvement in quality of life evaluated with the Glasgow Children's Benefit Inventory; rate and type of surgical complications. RESULTS: The mean preoperative air- and bone-conduction thresholds were 51.2±12.5 and 14.1±6.3dB HL, respectively. The mean preoperative threshold with a conventional bone-conduction hearing aid was 29.3±7.2dB HL, and the mean postoperative threshold with the Baha system was 18.1±7.5dB HL. Quality of life improved for all operated patients. CONCLUSIONS: The results of our study of the Baha system to treat patients with bilateral aural atresia were extremely satisfactory compared both with those of surgical reconstruction of the auditory canal and those of traditional bone-conduction hearing aids. Furthermore, great improvement was noted in quality of life, while the rate of complications was very low. Therefore, we are convinced that the Baha system is the treatment of choice for hearing loss due to bilateral congenital aural atresia.