Preserve Hearing Function Research Articles

Endolymphatic sac and duct as an anatomical repair to achieve complete exposure of the internal auditory canal through the retrosigmoid approach: Anatomical study.

The retrosigmoid approach (RSA) is used in a wide variety of pathologies in the cerebellopontine angle (CPA), especially according to the findings, it can preserve hearing function during the resection of vestibular schwannomas (VS). Complete exposure of the fundus of the internal auditory canal (IAC) could jeopardize the integrity of the otic capsule and subsequently cause profound hearing loss and chronic disabling vertigo. Great variability has been described in labyrinthine structures and to date there is no clear data on the distances of these structures to safely expose the IAC fundus. ObjectiveEstablish reference values of the endolymphatic sac and duct to achieve safe and complete exposure of the IAC through the RSA. MethodologyThis is a cross-sectional descriptive study where complete dissection of the endolymphatic sac and duct (ELSD) was performed on 20 preserved human temporal bones, measuring the distances of nine anatomical structures underlying or closely related to the ELSD. ResultsWhen evaluating the variability between the structures, the distance between the ELSD to the acoustic pore (AP) had little variability and remained constant in all specimens. The distance between the AP and the common cross (CC) presented in our study had the lowest coefficient of variation. The distance that had the greatest variability was the measurement of the jugular foramen (JF) both by retrosigmoid and translabyrinthine approaches (RSA-TLA). The rest of the variables remained stable. ConclusionsThe ELSD is a safe anatomical technique for dissection and exposure of the IAC during RSA in VS surgeries. In our study, the structures evaluated present little variability with the exception of the distances between the ELSD and the JF, which in some cases the JF exceeds the lower limit of the ELSD and IAC.

Resistance to age-related hearing loss in the echolocating big brown bat (Eptesicus fuscus).

Hearing mediates many behaviours critical for survival in echolocating bats, including foraging and navigation. Although most mammals are susceptible to progressive age-related hearing loss, the evolution of biosonar, which requires the ability to hear low-intensity echoes from outgoing sonar signals, may have selected against the development of hearing deficits in bats. Many echolocating bats exhibit exceptional longevity and rely on acoustic behaviours for survival to old age; however, relatively little is known about the ageing bat auditory system. In this study, we used DNA methylation to estimate the ages of wild-caught big brown bats (Eptesicus fuscus) and measured hearing sensitivity in young and ageing bats using auditory brainstem responses (ABRs) and distortion product otoacoustic emissions (DPOAEs). We found no evidence for hearing deficits in bats up to 12.5 years of age, demonstrated by comparable thresholds and similar ABR and DPOAE amplitudes across age groups. We additionally found no significant histological evidence for cochlear ageing, with similar hair cell counts, afferent and efferent innervation patterns in young and ageing bats. Here, we demonstrate that big brown bats show minimal evidence for age-related hearing loss and therefore represent informative models for investigating mechanisms that may preserve hearing function over a long lifetime.

The Effect of Thymoquinone on Acoustic Trauma-Induced Hearing Loss in Rats.

Background The aim of this study was to investigate the protective effect of thymoquinone, an antioxidant, on hearing loss induced by acoustic trauma in rats. Material and methods This study included 32 Wistar Albino rats divided into four groups: control, acoustic trauma, thymoquinone + acoustic trauma, and thymoquinone only, with eight rats per group. The control group received 0.5 mL of corn oil intraperitoneally for 10 days. The acoustic trauma group was exposed to 100 dB white noise at 4 kHz for 16 hours. The thymoquinone + acoustic trauma group received thymoquinone (10 mg/kg) intraperitoneally for two days before acoustic trauma and eight days after acoustic trauma. The thymoquinone only group received thymoquinone (10 mg/kg) for 10 days. Distortion product otoacoustic emissions (DPOAEs) were measured before and after treatments on days 1, 4, and 10. Results In the control group, DPOAE measurements showed no significant change over the study period. The acoustic trauma group exhibited a significant decrease in DPOAE on the first day after trauma, followed by some recovery. The thymoquinone + acoustic trauma group showed no significant decrease in DPOAE on the first day post-trauma, suggesting a protective effect. The thymoquinone only group also indicated no significant change in DPOAE measurements, suggesting that thymoquinone alone did not affect hearing function. Conclusion Thymoquinone demonstrated a protective effect against acoustic trauma-induced hearing loss in rats, as evidenced by stable DPOAE measurements post-trauma. These findings suggest that thymoquinone may help preserve hearing function by reducing oxidative stress in the cochlea. Further studies are needed to confirm these results in humans and optimize dosage and treatment protocols.

Modified infra-promontorium trans-channel approach to the petrous apex. Case report

This article describes the approach to the petrous pyramid developed at National Medical Research Center of Otorhinolaryngology, namely an endoscopy – microscopy-guided modified trans-channel infra-promontorium approach with internal carotid artery retraction maneuver in patients with lesions of the petrous pyramid but with preserved hearing. A clinical report describing the apical cholesteatoma of the petrous pyramid and the use of this approach are presented. Anatomical and functional features after the surgery are also described. The purpose of this paper is advancing of the surgical approach to the petrous pyramid with the possibility of hearing preservation. The results of surgical treatment in lesions of the petrous pyramid were evaluated in the immediate and distant periods. The functions of facial mimic muscles were evaluated immediately after the surgery, in 6 months, and in one year. The functions of facial mimic muscles remained at the baseline level during the whole follow-up period. The pure tone audiogram demonstrated the preserved hearing function in the postoperative period. Complete elimination of the pathological process was achieved in all cases (n=15); according to the MRI of the temporal bones, no relapses occurred in a year. The surgical approach proposed for patients with the lesions of the petrous pyramid enables complete removal of the pathological process from the petrous pyramid with the preservation of hearing and facial functions, based on the subjective examinations (audiometry, facial function diagnosis) and radiology (CT and MRI of temporal bones) at the preoperative stage.

Resistance to age-related hearing loss in the echolocating big brown bat ( Eptesicus fuscus ).

Hearing mediates many behaviors critical for survival in echolocating bats, including foraging and navigation. Most mammals are susceptible to progressive age-related hearing loss; however, the evolution of biosonar, which requires the ability to hear low-intensity echoes from outgoing sonar signals, may have selected against the development of hearing deficits in echolocating bats. Although many echolocating bats exhibit exceptional longevity and rely on acoustic behaviors for survival to old age, relatively little is known about the aging bat auditory system. In this study, we used DNA methylation to estimate the ages of wild-caught big brown bats ( Eptesicus fuscus ) and measured hearing sensitivity in young and aging bats using auditory brainstem responses (ABRs) and distortion product otoacoustic emissions (DPOAEs). We found no evidence for hearing deficits in aging bats, demonstrated by comparable thresholds and similar ABR wave and DPOAE amplitudes across age groups. We additionally found no significant histological evidence for cochlear aging, with similar hair cell counts, afferent, and efferent innervation patterns in young and aging bats. Here we demonstrate that big brown bats show minimal evidence for age-related loss of peripheral hearing sensitivity and therefore represent informative models for investigating mechanisms that may preserve hearing function over a long lifetime.

Endolymphatic duct blockage surgery vs. intratympanic steroids for treatment of refractory Ménière's disease.

To compare the effectiveness of the Endolymphatic duct blockage (EDB) and intratympanic methylprednisolone(ITMP) injection to control refractory Ménière's disease(MD) symptoms and evaluate their impact on hearing level. Retrospective study in a tertiary care center. 36 received ITMP injection and 52 EDB. Mean outcome measures at 24months included vertigo control, tinnitus, aural fullness and hearing level: pure-tone average (PTA), bone conduction average(BCA) and speech discrimination score(SDS). At 24months postoperatively, 90.4% of the EDB group had complete control of vertigo and 43.4% of the ITMP group (p = 0.001). There was no significant difference in tinnitus or aural fullness control (p = 0.34 and p 0.21 respectively). In each group, the drop in tinnitus and aural fullness frequency at 24months were significant for EDB (p = 0.03; p < 0.001 respectively) and for ITMP group in tinnitus (p = 0.03) but not aural fullness (p = 0.063). At 24months, PTA, BCA and SDS were significantly worst in the ITMP group when compared to preoperative levels (p = 0.038, p = 0.027, p = 0.016). PTA in the EDB group was stable with no difference compared to ITMP group (p = 0.48). BCA and SDS in the EDB group were stable and better than the ITMP group (p = 0.032; p = 0.036). In each group, vestibular paresis was not significantly different before (p = 0.06) and after treatment (p = 0.68). EDB is more effective than the ITMP for controlling the vertigo symptoms of Ménière's disease and in preserving hearing function. It is a novel surgical technique with promising results for a complete treatment of Ménière's disease. ITMP decreases the frequency and the severity of the symptoms but only control vertigo in 27.8% of cases.

Decoding the impact of autoinflammatory/autoimmune diseases on inner ear harmony and hearing loss

Autoimmune and autoinflammatory diseases affecting the inner ear can cause symptoms such as hearing loss, imbalance, vertigo, and tinnitus, presenting demanding and often underdiagnosed conditions. Diagnostic challenges arise due to their diverse manifestations, potential long-term consequences, and the absence of specific serological markers, necessitating a multidisciplinary approach combining clinical evaluation, audiological assessments, and imaging techniques. Various autoimmune disorders, including systemic lupus erythematosus, rheumatoid arthritis, and Sjogren’s syndrome, have been implicated in immune-mediated damage to auditory structures, resulting in inner ear dysfunction. Inflammatory processes in autoinflammatory diseases like Cogan’s syndrome and relapsing polychondritis can also affect the inner ear. While the exact mechanisms of inner ear involvement in these conditions are still being studied, immune-mediated inflammation, damage to auditory structures, and vascular involvement play significant roles in auditory impairments. Treatment strategies primarily focus on immunomodulation and inflammation control using corticosteroids, immunosuppressants, and targeted biologic agents to ameliorate symptoms and preserve hearing function. Hearing aids and cochlear implants may be also considered for severe hearing loss. Individualized approaches are necessary due to patient response heterogeneity. This review provides a concise overview of key autoimmune and autoinflammatory diseases impacting the inner ear, highlighting clinical manifestations, diagnostics, pathophysiology, and treatment options. Early recognition and appropriate management are crucial for optimizing patient outcomes. Further research is needed to understand underlying mechanisms and identify novel therapeutic targets. Collaboration between otolaryngologists, rheumatologists, and immunologists is crucial for improving the quality of life in these complex conditions.

Decoding the impact of autoinflammatory/autoimmune diseases on inner ear harmony and hearing loss

Autoimmune and autoinflammatory diseases affecting the inner ear can cause symptoms such as hearing loss, imbalance, vertigo, and tinnitus, presenting demanding and often underdiagnosed conditions. Diagnostic challenges arise due to their diverse manifestations, potential long-term consequences, and the absence of specific serological markers, necessitating a multidisciplinary approach combining clinical evaluation, audiological assessments, and imaging techniques. Various autoimmune disorders, including systemic lupus erythematosus, rheumatoid arthritis, and Sjogren’s syndrome, have been implicated in immune-mediated damage to auditory structures, resulting in inner ear dysfunction. Inflammatory processes in autoinflammatory diseases like Cogan’s syndrome and relapsing polychondritis can also affect the inner ear. While the exact mechanisms of inner ear involvement in these conditions are still being studied, immune-mediated inflammation, damage to auditory structures, and vascular involvement play significant roles in auditory impairments. Treatment strategies primarily focus on immunomodulation and inflammation control using corticosteroids, immunosuppressants, and targeted biologic agents to ameliorate symptoms and preserve hearing function. Hearing aids and cochlear implants may be also considered for severe hearing loss. Individualized approaches are necessary due to patient response heterogeneity. This review provides a concise overview of key autoimmune and autoinflammatory diseases impacting the inner ear, highlighting clinical manifestations, diagnostics, pathophysiology, and treatment options. Early recognition and appropriate management are crucial for optimizing patient outcomes. Further research is needed to understand underlying mechanisms and identify novel therapeutic targets. Collaboration between otolaryngologists, rheumatologists, and immunologists is crucial for improving the quality of life in these complex conditions.

Intraoperative Monitoring During Microvascular Decompression

During microvascular decompression(MVD)for hemifacial spasm(HFS), trigeminal neuralgia(TN), and glossopharyngeal neuralgia(GPN), brainstem auditory-evoked potential monitoring is widely used to preserve hearing function. In MVD for HFS, abnormal muscle response monitoring is useful for identifying the offending vessels compressing the facial nerve and confirming the completion of decompression intraoperatively. The amplitude of facial motor-evoked potential by transcranial electrical stimulation in the orbicularis oculi muscle is reported to decrease after completing MVD. The Z-L response(ZLR)probably confirms the true offending vessels by stimulating the culprit vessels; then, the ZLR could disappear after decompressing the offending vessels away from the compression sites. Spontaneous electromyographic activities obtained from the mentalis muscles by injection of saline into the facial nerve reportedly decreased after MVD compared with those before MVD. In MVD for the GPN, glossopharyngeal motor-evoked potential by transcranial electrical stimulation is used to preserve swallowing function and not to assess the completion of MVD. Because MVD for both the TN and GPN can result in normalization of the hyperactivity of the sensory nerve, it may be difficult to develop any monitoring to confirm the completion of MVD during surgery.

Intraoperative Monitoring during Microvascular Decompression for Hemifacial Spasm

Brainstem auditory evoked potential(BAEP)and abnormal muscle response(AMR)monitoring are widely used during microvascular decompression(MVD)for hemifacial spasm(HFS). In BAEP monitoring, the intraoperative findings of wave V do not necessarily predict postoperative hearing function. However, if a warning sign as significant as wave V change appears, the surgeon must abort the operation or inject artificial cerebrospinal fluid into the VIII nerve. During MVD for HFS, BAEP monitoring must be performed to preserve hearing function. AMR monitoring is useful in identifying the offending vessels compressing the facial nerve and confirming the completion of decompression intraoperatively. During the operation of the offending vessels, AMR sometimes changes its onset latency and amplitude in real time. These findings allow surgeons to identify the offending vessels. Even if the AMRs remain after completion of decompression, a decrease in amplitude of more than 50% compared to baseline is predictive of postoperative loss of HFS in long-term outcomes. When the AMRs disappear after dural opening, the AMR monitoring should be continued because the AMRs sometimes reappear.

Auditory Brainstem Response: ABR

Intraoperative auditory brainstem response(ABR)monitoring has been established as a reliable method to evaluate cochlear function. Intraoperative ABR is mandatory in microvascular decompression for hemifacial spasm, trigeminal neuralgia, and glossopharyngeal neuralgia. Cerebellopontine tumor with remaining effective hearing function also requires ABR monitoring during surgery to preserve hearing function. Prolonged latency and subsequent amplitude decrease in the ABR wave V predicts postoperative hearing impairment. Therefore, when alerted to an intraoperative ABR during surgery, the surgeon should release the cerebellar retraction stressing the cochlear nerve and wait for the abnormal ABR to recover.

Vestibular schwannoma associated with neurofibromatosis type 2: Clinical course following stereotactic radiosurgery.

ObjectiveA lack of understanding of the clinical course of neurofibromatosis type 2 (NF2)-associated vestibular schwannoma (VS) often complicates the decision-making in terms of optimal timing and mode of treatment. We investigated the outcomes of stereotactic radiosurgery (SRS) in this population.MethodsWe retrospectively analyzed NF2 patients treated with Gamma-Knife SRS for VS in our tertiary referral center. A total of 41 treated lesions from 33 patients were collected with a follow-up period of 69.1 (45.0-104.8) months. We reviewed the treatment history, hearing function, and other treatment-related morbidities in individual cases. We also analyzed pre- and post-treatment tumor volumes via imaging studies. Longitudinal volumetric analyses were conducted for the tumor volume response of the 41 treated lesions following SRS. The growth pattern of 22 unirradiated lesions during an observation period of 83.4 (61.1-120.4) months was separately evaluated.ResultsMost treated lesions showed effective tumor control up to 85% at 60 months after SRS, whereas unirradiated lesions progressed with a relative volume increase of 14.0% (7.8-27.0) per year during the observation period. Twelve (29%) cases showed pseudoprogression with significant volume expansion in the early follow-up period, which practically reduced the rate of tumor control to 57% at 24 months. Among the patients with serviceable hearing, two (20%) cases lost the hearing function on the treated side during the early follow-up period within 24 months.ConclusionsProgressive NF2-associated VS can be adequately controlled by SRS but the short-term effects of this treatment are not highly advantageous in terms of preserving hearing function. SRS treatment candidates should therefore be carefully selected.

Surgical Management of Intractable Meniere's Disease.

Meniere's Disease (MD) is an inner ear disorder characterized by spontaneous recurrent vertigo, fluctuating sensorineural hearing loss, aural fullness and low-pitch tinnitus. Therapeutic management of MD includes dietary restriction and medical therapy. A minority of cases is characterized by frequent vertigo attacks, progressive hearing loss and persistent tinnitus even through the continuous medical treatments; this condition is called intractable MD and requires a therapeutic escalation from non-invasive medical treatment to surgical intervention. Invasive procedures include endolymphatic sac surgery, vestibular nerve section and labyrinthectomy. These procedures have a very high success rate on symptom control but may have a severe impact on the hearing function. However, the simultaneous combined approach of demolitive surgery and cochlear implantation may be a valid approach to treat symptoms of intractable MD and preserve hearing function. In the present study, we review current literature focusing on intractable MD to describe and discuss advantages and disadvantages of established and newly proposed surgical treatments for intractable MD.

Petrous Bone Cholesteatoma: Facial and Hearing Preservation.

Objectives: Petrous bone cholesteatoma (PBC) is a rare condition of the petrous portion of the temporal bone. Treatment of choice consists of radical surgical removal, paying attention to protect the facial nerve and inner ear as far as possible. The aim of the present study was to evaluate the efficacy of modified translabyrinthine techniques in preserving hearing function and the use of the adjuvant endoscopic techniques in a group of PBC patients. Methods: This study comprised 16 cases of PBCs surgically treated in our Department. Pre- and post-operative hearing status was assessed with pure tone audiometry and speech discrimination and graded according to the Gardner- Robertson classification system. Facial function was based on the House Brackman (HB) classification. PBCs were grouped using Sanna's classification. The choice of surgical technique was based on the above findings together with preoperative evidence. Post-operative follow-up ranged from 1 to 10 years and also included Computed Tomography and Magnetic Resonance Imaging assessment. Results: PBCs were classified as follows: 37.5% infralabyrinthine; 43.75% supralabyrinthine; and 18.75% massive. Preservation of the bone conduction threshold was feasible in 62.5% of patients. For supralabyrinthine PBCs a subtotal petrosetomy was performed in all cases and hearing preservation was possible in 57% of them: an adjuvant endoscopic approach was performed in 43%. Infralabyrinthine PBCs were treated using a modified translabyrinthine approach with preservation of bone conduction in 83% of patients; an adjuvant endoscopic approach was performed in 50% cases. One patient with a massive cholesteatoma was treated by modified translabyrinthine approach, preserving a serviceable level of hearing. In all massive cases, an adjuvant endoscopic approach was performed. In 2 patients with preoperative palsy, facial nerve function showed an improvement. The follow-up period revealed evidence of limited recurrence at CT imaging in 2 patients. Conclusions: The introduction of modified surgical approaches, able to preserve the anatomical-functional structures, have shown an improvement of post-operative hearing outcomes.

Clinical characteristics of otogenic lateral sinus thrombosis in patients under 18 years old compared with that in adult patients

Background Otogenic lateral sinus thrombosis (OLST) is a rare complication of otitis media. We do not know whether the disease progress between the pediatric and adult OLST patients is consistent. However, pediatric surgical methods always refer to the adults'. Aims/objectives This study aimed to seek evidence for suitable surgical methods in pediatric patients. Materials and methods The clinical manifestation, laboratory findings, and findings in operation between children and adult groups were compared. Results Ten children and 17 adults OLST patients were included. Most pediatric patients had no history of chronic otitis media or cholesteatoma (p<.001). The ratios of otorrhea, tympanic perforation and sclerotic type mastoid in CT scan were significantly lower in the children group (p<.05). The mean air conduction hearing threshold in the children and adolescent group (31.25 ± 21.27 dB) was significantly lower than that of the adult group (77.6 ± 23.66 dB) (p<.001). The diseases in attics (66.7%) and the ossicular chain destruction (33.3%) were not as severe as those in the adult group (p<.05). The eustachian tube closure was found similar in two groups. Conclusions and significance Conservative surgery is recommended to pediatric OLST to obliterate the diseases and improve middle ear and mastoid drainage, preserving hearing function.

Long-term prognosis of preserved useful hearing after surgery in patients with vestibular schwannoma: a study of 91 cases.

In patients with a vestibular schwannoma, some studies have reported that useful hearing preserved initially after surgery deteriorates gradually in the long term. Studies with more patients are needed to clarify the maintenance rate of postoperative hearing function and to identify prognostic of hearing function. Ninety-one patients (mean age, 39.5 years; mean tumor size, 18.9 mm) with preserved useful hearing immediately after surgery were retrospectively analyzed. The useful hearing was defined as the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) classes A and B. Hearing tests, including auditory brainstem responses (ABR) and distortion product otoacoustic emissions (DPOAE), were evaluated preoperatively, immediately after surgery, and at outpatient follow-up. At the final follow-up (mean, 63.0 months), the useful hearing was maintained in 79 patients (87%), and the hearing class remained unchanged during the follow-up period in 40 patients (44%). Significant predictors of useful hearing maintenance were AAO-HNS class A immediately after surgery, improvement of ABR, and the absence of postoperative DPOAE deterioration. Postoperative DPOAE deterioration correlated with hearing class deterioration. Despite hearing being preserved in vestibular schwannoma patients immediately after surgery, Thirteen percent lost their useful hearing during the long follow-up period, and hearing class worsened in 55% of the patients. This study, which analyzed one of the largest series of vestibular schwannoma patients, demonstrated that retrocochlear condition is a key factor for useful hearing maintenance. In patients with vestibular schwannoma who have preserved hearing function, regular postoperative monitoring of hearing function is as important as regular MRI.

Keyhole Retrosigmoid Craniotomy for Resection of Pontine Juvenile Pilocytic Astrocytoma: 2-Dimensional Operative Video.

Resection of intrinsic brainstem tumors is fraught with a high risk of morbidity. In select cases, however, complete tumor resection is possible and can result in long-term benefit to the patient. Informed consent for the operation was obtained. In this video, we illustrate the use of a keyhole retrosigmoid craniotomy for microsurgical resection of an exophytic juvenile pilocytic astrocytoma and highlight the nuances of opening the various fissures between the brainstem and the cerebellum to obtain a more direct view of the brainstem, mapping of the brainstem surface to avoid cranial nerve nuclei, use of safe entry zones to minimize injury to critical structures, and microsurgical technique used to operate within the substance of the brainstem. In general, navigation is used to optimize placement of craniotomy and size of bony opening, to delineate the superior to inferior extent of the tumor, and to confirm that the boundary between the tumor and the normal brainstem is reached at the depth. In general, the authors attempt surgical resection of brainstem tumors that are exophytic, have clear boundaries (signal on T1 postcontrast and T2 sequences denote similar tumor boundaries), do not encapsulate the basilar artery, and do not exhibit infiltration of the deep pontine fibers (as is the case with diffuse intrinsic pontine gliomas). In properly selected patients, surgery for brainstem tumor can result in good resection with preservation of neurological function. This patient developed subtle weakness of the face after surgery, which did not improve at 3 mo, but had preserved hearing function and no further neurological deficits.

Effect of Specific Retinoic Acid Receptor Agonists on Noise-Induced Hearing Loss.

Noise is one of the most common causes of hearing loss in industrial countries. There are many studies about chemical agents to prevent noise-induced hearing loss (NIHL). However, there is no commercially available drug yet. Retinoic acid is an active metabolite of Vitamin A; it has an anti-apoptic role in NIHL. This study aims to verify the differences among selective agonists of retinoic acid receptors (RARs) in NIHL. All-trans retinoic acid (ATRA), AM80 (selective retinoic acid receptor α agonist), AC261066 (Selective retinoic acid receptor β1 agonist), and CD1530 (Selective retinoic acid λ agonist) were injected to 6–7 weeks old CJ5BL/6 mice before noise (110 dB for 3 h) exposure. In the auditory brainstem response test pre-, post 1, 3, and 7 days after noise exposure, not only ATRA but all kinds of selective RAR agonists showed protective effects in hearing threshold and wave I amplitude. Though there was no significant difference in the level of protective effects between agonists, α agonist showed the most prominent effect in preserving hearing function as well as outer hair cells after noise exposure. In conclusion, selective agonists of RAR demonstrate comparable protective effects against NIHL to retinoic acid. Given that these selective RAR agonists have less side effects than retinoic acid, they may be promising potential drugs against NIHL.

Combined Petrosal Approach for Resection of Petroclival Meningioma with Endoscopic Assistance: Operative Video and Technical Nuances.

Petroclival meningiomas are formidable lesions due to their deep location in the skull base and proximity to critical neurovascular structures. The combined petrosal approach, comprised of an anterior petrosectomy and posterior retrolabyrinthine petrosectomy, allows for both supra- and infratentorial exposure of the tumor in the petroclival region while potentially preserving hearing function ( Fig. 1 ). In this operative video atlas manuscript, the authors demonstrate a step-by-step technique for microsurgical resection of a petroclival meningioma via the combined petrosal approach. The nuances of microsurgical and skull base technique are illustrated including drilling of the petrous bone, transecting the tentorium, resection of the tumor, and multilayered reconstruction of the dural defect. The combined petrosal approach allows for multiple angles of attack including both subtemporal and presigmoid corridors. In summary, the combined petrosal approach with endoscopic assistance is an important strategy in the armamentarium for surgical resection of petroclival meningiomas ( Fig. 2 ). The link to the video can be found at: https://youtu.be/ipZb9kHcP2g .

Audiological outcome for hearing preservation surgery in acoustic neuroma: the need of agreement in reporting results

Purpose: Early diagnosis in acoustic neuroma (AN) has increased the prevalence of small tumors with good hearing. Otoneurological centres have increasingly aimed to preserve hearing function. The managementoptions of small ANs range from observation to active treatments (surgery, radiotherapy). No firm agreement has been made on which is the best option for audiological function preservation. Nowadays, no definitive guidelines are present in order to suggest a standard way of evaluating and comparing the hearing quality. The lack of a universally agreed hearing classification leads to the impossibility of comparing data from different centres or different therapeutic options.Method: The paper wantst o show, analyzing our surgical experience in hearing preservation surgery for ANs, the different results that are demonstrable by just using different hearing classification.Results: About the 13 patients considered ‘in protocol’ who underwent HPS, 69% are considered to have ‘good’ hearing after surgery using the Tokyo or Sanna classifications; with the AAO-HNS or the GR classifications the outcome of ‘good’ hearing preservation was 77% and in 87% with the WRS classification.Conclusion: A shared hearing classification is potentially the solution in order to facilitate comparison of functional outcomes across different centres or different treatment modalities.