Effectiveness of Hypoglossal-Facial Anastomosis in the Rehabilitation of Facial Paralysis Following Vestibular Schwannoma Surgery: A Systematic Review

The facial nerve plays a crucial role in facial expression and sensory functions, with irreversible injuries often demanding rehabilitation therapies, with hypoglossal-facial nerve anastomosis (HFA) being one of the treatment options. This systematic review assessed different HFA techniques for facial paralysis, particularly post vestibular schwannoma resection, focusing on effectiveness and associated morbidities. Fifteen studies, comprising a case series and a retrospective cohort, were analyzed. Techniques included end-to-end, split, side-to-side, end-to-side, and jump interpositional graft hypoglossal-facial anastomosis (JIGHFA). Positive outcomes were observed with end-to-end and side-to-side techniques, while the split technique and JIGHFA showed promise. Comparative analyses favored the 'end-to-side' approach. Shorter intervals between surgery and HFA correlated with improved outcomes. Methodological variations highlight the need for prospective studies with standardized methodologies for robust evidence and informed decision-making on optimal HFA techniques.

Asymmetry of the anterior ethmoidal artery in relation to the anterior skull base: a population-based study of 500 arteries

OBJECTIVE

To analyze variability in the distance between the Anterior Ethmoidal Artery (AEA) and the anterior Skull Base (SB), as well as the frequency of lateral asymmetry in a Latin American population using computed tomography.

METHODS

A total of 250 computed tomography scans of paranasal sinuses in coronal reconstruction (500 AEAs) were analyzed. After determining the image with the best anatomical view of the artery, the distance between its midpoint and the ethmoidal roof was measured, and the images were independently interpreted by 2 physicians.

RESULTS

Of the 500 AEAs, 279 (55.8%) adhered to or passed through the SB at a distance of 0mm. A total of 221 AEAs (44.2%) were at some distance from the SB, of which 107 (48.4%) were on the right side, ranging from 1.18 to 6.75mm, and 114 (51.5%) were on the left side, ranging from 1.15 to 6.04mm. The overall mean distance between the AEA and SB was 1.22 (SD=1.57) mm, increasing to 2.77 (SD=1.14) when the arteries adhered to the SB were excluded. Seventy-six individuals (30.4%) had a lateral distance variation > 1mm.

CONCLUSION

Our study includes the largest sample of AEA analyzed with computed tomography scans of paranasal sinuses. There was some distance between the AEA and SB in almost half the patients, and we found a high rate of lateral variability >1mm.

LEVEL OF EVIDENCE

Level 3.

Anteromedial Petrous (Gardner's) Triangle: Surgical Anatomy and Relevance for Endoscopic Endonasal Approach to the Petrous Apex and Petroclival Region

BACKGROUND AND OBJECTIVES

Triangular corridors have been used as reliable surgical entry points for open transcranial approaches to the petrous apex (PA) and petroclival region (PCR). The endoscopic endonasal approaches have grown rapidly in the last decade, and the indications have advanced. The knowledge of accurate and reliable anatomic landmarks through endoscopic endonasal route is essential and remain to be established. The purpose of this study was to describe the feasibility and surgical exposure of the anteromedial petrous (Gardner's) triangle as a novel corridor to the PA and PCR.

METHODS

Five anatomic specimens were dissected. The PA and PCR were accessed through endoscopic endonasal approaches and contralateral transmaxillary approach. The limits of the anteromedial petrous (Gardner's) triangle were identified and dissected and associated measurements performed.

RESULTS

The dissection was divided into 6 steps. The limits of the anteromedial petrous (Gardner's) triangle were identified and defined by the paraclival internal carotid artery anterolaterally, the abducens nerve posteromedially, and the petroclival synchondrosis inferiorly. Three lines were established following the limits of the triangle. The mean distance of the anterolateral limit was 10.03 mm (SD = 0.94), of the posteromedial limit was 20.06 mm (SD = 2.90), and of the inferior limit was 17.99 mm (SD = 2.99). The mean area was 87.56 mm 2 (SD = 20.06). The 3 anatomic landmarks with a critical role to safely define the triangle were the pterygosphenoidal fissure, the petrosal process of the sphenoid bone, and the petroclival synchondrosis.

CONCLUSION

The anteromedial (Gardner's) triangle is a well-defined bone corridor which provides access to the entire petrous bone and petroclival junction through endoscopic endonasal route. Regardless of the anatomic variations or tumor location, the landmarks of the abducens nerve, paraclival internal carotid artery, and petroclival synchondrosis are key for understanding lateral access to tumors extending from the clivus.

Task force of the Brazilian Society of Otology - evaluation and management of peripheral facial palsy

OBJECTIVE

To review key evidence-based recommendations for the diagnosis and treatment of peripheral facial palsy in children and adults.

METHODS

Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on peripheral facial palsy were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions.

RESULTS

The topics were divided into 2 main parts: (1) Evaluation and diagnosis of facial palsy: electrophysiologic tests, idiopathic facial palsy, Ramsay Hunt syndrome, traumatic peripheral facial palsy, recurrent peripheral facial palsy, facial nerve tumors, and peripheral facial palsy in children; and (2) Rehabilitation procedures: surgical decompression of the facial nerve, facial nerve grafting, surgical treatment of long-term peripheral facial palsy, and non-surgical rehabilitation of the facial nerve.

CONCLUSIONS

Peripheral facial palsy is a condition of diverse etiology. Treatment should be individualized according to the cause of facial nerve dysfunction, but the literature presents better evidence-based recommendations for systemic corticosteroid therapy.

Non-Hodgkin Lymphoma Mimicking Vestibular Schwannoma

Progressive unilateral hearing loss and an MRI are usually enough to diagnose vestibular schwannoma (VS). We were consulted by a 45-year-old man with otalgia and left-sided hearing loss as well as ipsilateral facial paralysis that had begun two weeks prior. Due to a possible atypical presentation of VS, an MRI was ordered, which revealed an intracanalicular lesion occupying the left cerebellopontine angle cistern. With no signs of systemic disease and considering the total left ear deafness, the patient underwent retrolabyrinthine mastoidectomy. During the procedure, a mass incompatible with VS was found and a biopsy was performed, which led to a diagnosis of non-Hodgkin's lymphoma (NHL). The patient was referred to an oncologist for treatment and, in time, achieved complete remission of the lesion. This case shows us that symptoms of VS may vary in tumor size and location and that atypical presentations warrant investigation. Non-Hodgkin's lymphoma (NHL), although not among the most common differential diagnoses, should be remembered due to its varied clinical presentation broadly dependent on its subtype and dissemination.

Brazilian Society of Otology task force - Otosclerosis: evaluation and treatment

OBJECTIVES

To review and provide evidence-based recommendations for the diagnosis and treatment of otosclerosis.

METHODS

Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on otosclerosis were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions.

RESULTS

The topics were divided into 2 parts: 1) Diagnosis - audiologic and radiologic; 2) Treatment - hearing AIDS, pharmacological therapy, stapes surgery, and implantable devices - bone-anchored devices, active middle ear implants, and Cochlear Implants (CI).

CONCLUSIONS

The pathophysiology of otosclerosis has not yet been fully elucidated, but environmental factors and unidentified genes are likely to play a significant role in it. Women with otosclerosis are not at increased risk of worsening clinical condition due to the use of contraceptives or during pregnancy. Drug treatment has shown little benefit. If the patient does not want to undergo stapedotomy, the use of hearing aids is well indicated. Implantable systems should be indicated only in rare cases, and the CI should be indicated in cases of profound deafness.

Brazilian Society of Otology task force - Vestibular Schwannoma ‒ evaluation and treatment

OBJECTIVE

To review the literature on the diagnosis and treatment of vestibular schwannoma.

METHODS

Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on vestibular schwannoma were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions.

RESULTS

The topics were divided into 2 parts: (1) Diagnosis - audiologic, electrophysiologic tests, and imaging; (2) Treatment - wait and scan protocols, surgery, radiosurgery/radiotherapy, and systemic therapy.

CONCLUSIONS

Decision making in VS treatment has become more challenging. MRI can diagnose increasingly smaller tumors, which has disastrous consequences for the patients and their families. It is important to develop an individualized approach for each case, which highly depends on the experience of each surgical team.

Facial Nerve Hemangioma of the Lateral Portion of the Internal Acoustic Canal: A Case Report and a Review of Literature

Introduction  Facial nerve hemangiomas (FNH) are rare tumors. Although it can occur in any portion of the nerve, it predominantly appears near the geniculate ganglion. We present a case of facial nerve hemangioma of an unusual location. Case Report  A 30-year-old woman presented with right-sided severe hearing loss and progressive facial palsy. Magnetic resonance showed a 5 mm lesion in the lateral portion of the right internal auditory canal. Due to facial palsy, the patient was submitted to a translabyrinthine approach and a total tumor resection, followed by hypoglossal-facial nerve anastomosis. Discussion  The facial nerve is susceptible in its path to expansive lesions, which have high morbidity. FNH is a rare and difficult-to-diagnose lesion. Computerized tomography and nuclear magnetic resonance can be used in its diagnosis. The differential diagnosis of FNH includes, in addition to schwannomas, meningiomas, cholesteatomas, paragangliomas, and other temporal bone tumors. There is no well-established consensus on the best approach. Because of its slow growth and benign behavior, some studies suggest conservative treatment and serial imaging. However, surgery is the cornerstone of treatment, as it is the only curative option. Conclusion  FNHs are often small but very symptomatic. Its high morbidity demands early diagnosis and, sometimes, surgical treatment.

Are hearing protection devices used in the workplace really efficient? A systematic review

BACKGROUND

The most common current hearing protection devices (HPDs) on the market include earplugs and earmuffs. A variety of materials can be used to manufacture these devices, and each offers a level of noise attenuation that is informed by the manufacturer although it does not always correspond to the attenuation observed in real-world use.

OBJECTIVE

To evaluate the noise attenuation of HPDs available to workers exposed to noise.

METHODS

The most relevant studies originally published in English, Portuguese, or Spanish that investigated the noise attenuation effectiveness of HPDs used by workers exposed to noise were analyzed. The following electronic databases were searched by 2 independent reviewers for studies published from 1999 to 2019: MEDLINE (PubMed), Scopus, Web of Science, EMBASE, Cochrane Library (OVID), ProQuest, and BVS-Bireme. Different combinations of the following search terms (MeSH terms) were used for all databases: "Hearing Loss, Noise-Induced", "Ear Protective Devices" (Efficacy OR Effectiveness)", "Noise, Occupational".

RESULTS

The search strategy yielded a total of 326 potentially relevant studies. After the removal of duplicates, 156 remained for the screening of titles and abstracts. After reviewing titles and abstracts, 46 studies were selected for full-text reading. Of these, six were included in this systematic review.

CONCLUSION

Hearing protection devices reduced the noise exposure and were effective in all included studies in different countries, types of activity, and sound pressure exposure.

The Learning Curve in Skullbase Surgery Part 2–From the Microsurgical Lab Training to the Operative Room

In this second part, the authors review and suggest a methodology for studies in skull base surgery and training in microsurgical laboratory, based on their experiences and reflections. Not only are the foundations for the acquisition of microsurgical skills presented, but also what is needed to be an effective skullbase surgeon with good results. The present article reflects in particular the philosophy of professor Evandro de Oliveira and also serves to present to the neurosurgical community a new state-of-the-art laboratory for hands-on courses in Brazil, at the Faculdade Evangélica Mackenzie do Paraná.

The Learning Curve in Skull Base Surgery Part 1–From Historical-Philosophical Concepts to Microsurgical Lab Training

The learning curve reflects surgeons' experience in managing several patients with the same disease. In skull base surgery, the professional's place on the curve could be related to the number of times the same procedure was performed. Where does curve begin? What amount of training is necessary prior to its application in surgical settings? What were the results of the first few skull base tumor surgeries performed by a surgeon who goes on to produce excellent results, and how is reflected in the start of their learning curve? The only way for neurosurgeons to improve their results from the start is with prior training in the microsurgery laboratory. This learning technique is essential to maximize the chance of success of a neurosurgical procedures, minimizing the morbidity rate to which patients are subjected by less experienced neurosurgeons. This article is divided in two parts, and its purpose is to show how training in the microsurgical laboratory fits into the construction of knowledge about skull base surgery, based on authors' experience and reflections. This first part discusses the technical, psychological, and philosophical aspects of medical knowledge, primarily addressing those training in skull base surgery, the principles of some selected philosophical currents, and their influence on the development of current medical knowledge.

Task force Guideline of Brazilian Society of Otology ‒ hearing loss in children - Part I ‒ Evaluation

OBJECTIVES

To provide an overview of the main evidence-based recommendations for the diagnosis of hearing loss in children and adolescents aged 0 to 18 years.

METHODS

Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on childhood hearing loss were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions.

RESULTS

The evaluation and diagnosis of hearing loss: universal newborn hearing screening, laboratory testing, congenital infections (especially cytomegalovirus), genetic testing and main syndromes, radiologic imaging studies, vestibular assessment of children with hearing loss, auditory neuropathy spectrum disorder, autism spectrum disorder, and noise-induced hearing loss.

CONCLUSIONS

Every child with suspected hearing loss has the right to diagnosis and appropriate treatment if necessary. This task force considers 5 essential rights: (1) Otolaryngologist consultation; (2) Speech assessment and therapy; (3) Diagnostic tests; (4) Treatment; (5) Ophthalmologist consultation.

Task force Guideline of Brazilian Society of Otology - hearing loss in children - Part II - Treatment

OBJECTIVES

To provide an overview of the main evidence-based recommendations for the diagnosis of hearing loss in children and adolescents aged 0-18 years.

METHODS

Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on childhood hearing loss were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions.

RESULTS

The topics were divided into 2 parts: (1) treatment of sensorineural hearing loss: individual hearing aids, bilateral cochlear implants, cochlear implants in young children, unilateral hearing loss, and auditory neuropathy spectrum disorder; and (2) treatment of conductive/mixed hearing loss: external/middle ear malformations, ventilation tube insertion, and tympanoplasty in children.

CONCLUSIONS

In children with hearing loss, in addition to speech therapy, Hearing AIDS (HAs) or implantable systems may be indicated. Even in children with profound hearing loss, both the use of HAs and behavioral assessments while using the device are important.

Abordajes quirúrgicos de los meningiomas petroclivales Parte 2: revisión narrativa y lo que aprendimos con 30 casos

Antecedentes:

La resección quirúrgica de los meningiomas petroclivales es un desafío debido a su ubicación profunda y su relación con las estructuras neurovasculares vitales. Por lo general, son lesiones benignas, pero pueden involucrar o infiltrar huesos en la base del cráneo, la duramadre y el tronco encefálico. Esto hace que la extirpación total sea muy difícil o imposible sin causar déficits neurológicos. El objetivo de este estudio es revisar los abordajes quirúrgicos utilizados para tratar los meningiomas petroclivales y las lecciones que hemos aprendido en el manejo quirúrgico de 30 casos.

Métodos:

Serie de casos de 30 meningiomas petroclivales. Al comienzo de nuestra serie, utilizamos el abordaje petroso para todos los casos, pero con la adquisición de experiencia comenzamos a indicar cada vez más el abordaje retrosigmoideo, reservando los abordajes petrosos y cráneo-orbitocigomático para casos seleccionados.

Resultados:

Debido a la dificultad de acceso, los meningiomas petroclivales generalmente requieren diferentes abordajes quirúrgicos y presentan diferentes dificultades quirúrgicas. Hay tres abordajes principales: fronto-orbito-cigomático y variantes; petroso y variantes; y retrosigmoideo, pudiendo ser combinados. La elección del abordaje quirúrgico generalmente se basa en la ubicación y extensión del tumor, la forma del cráneo y la participación de las estructuras venosas, y la experiencia del cirujano.

Conclusión:

Los meningiomas petroclivales son raros y complejos en la base del cráneo. Elegir el abordaje correcto es crucial para un resultado quirúrgico exitoso.

SARS‐CoV ‐2 infection with bilateral intralabyrinthine hemorrhage

A 47‐year‐old woman presented with the complaint of sudden hearing loss associated with vertigo. Serological testing was positive for IgM and negative for IgG COVID‐19 antibodies, with no other associated factors. Magnetic resonance imaging of the brain showed bilateral intralabyrinthine hemorrhage.

This is a rare case of bilateral intralabylinthine hemorrhage after COVID‐19 infection. The mechanism is unclear, but clinicians should keep this case in mind when you see sudden hearing loss with vertigo, and early intervention should be considered.

Progressive Asymmetry in Occupational Noise-Induced Hearing Loss: A Large Population-Based Cohort Study With a 15-Year Follow-Up

BACKGROUND

To evaluate interaural differences between the right and left ears at frequencies from 0.25 to 8 kHz in 3 groups of workers from metallurgy companies.

METHODS

This study is a cross-sectional cohort study. Workers were divided into 3 groups: (1) workers without occupational noise exposure and normal audiometric testing; (2) workers with 10 years of occupational noise exposure; and (3) workers with 15 years of occupational noise exposure. The interaural difference from 0.25 to 8 kHz was measured in each group.

RESULTS

A total of 2103 workers were included. Of these, 483 workers had been exposed to noise in the workplace for 10 years and 216 workers for 15 years. Group 1, only at 4 and 6 kHz, the difference was statistically significant. Group 2, only at 3 , 4 , and 6 kHz, the difference was statistically significant. Group 3, the difference was statistically significant at the frequencies from 2 to 8 kHz.

CONCLUSION

Asymmetry between the right and left ears was observed in all groups, with higher air-conduction thresholds in the left ear. It is important for otolaryngologists be aware that NIHL can also cause or accentuate asymmetry between the right and left ears over time.

Image-guided Temporal Bone Dissection Course

Introduction  Temporal bone anatomy is complex and demands a profound anatomical knowledge. Association between surgery and imaging helps in the process of learning three-dimensional (3D) anatomy and surgical techniques. High definition temporal bone imaging can play an important role in dissection training. Objective  To describe a computed tomography (CT) image-guided temporal bone dissection course for surgical training in otolaryngology and to verify the satisfaction level of the students with the course. Methods  Descriptive research. The course took place at a research laboratory, with three experienced temporal bone surgeons. The participants were 12 otolaryngology residents. The laboratory has 7 modern workstations with microscope and monitors linked with a computerized video system. Cadaveric temporal bones were donated to the university. Imaging acquisition of the cadaveric temporal bones used in the course was performed in a multislice CT scanner. The CT images of cadaveric temporal bones were available with real-time access on the laboratory monitor's screens during dissections. Results  A total of 13 temporal bones were included for dissection. Students had the opportunity to view on the same screen, simultaneously, both the dissection video and the respective CT images of their temporal bone anatomical specimens. This allowed correlating surgical and imaging aspects of temporal bone anatomy. At the end of the course, participants answered a satisfaction survey. Conclusion  Considering imaging methods are routinely used during most otologic surgeries, detailed knowledge of CT imaging should be explored in conjunction with the temporal bone anatomical dissection.

Noise Exposure and Distortion Product Otoacoustic Emission Suprathreshold Amplitudes: A Genome-Wide Association Study

BACKGROUND

Although several candidate-gene association studies have been conducted to investigate noise-induced hearing loss (NIHL) in humans, most are underpowered, unreplicated, and account for only a fraction of the genetic risk. Mouse genome-wide association studies (GWASs) have revolutionized the field of genetics and have led to the discovery of hundreds of genes involved in complex traits. The hybrid mouse diversity panel (HMDP) is a collection of classic inbred and recombinant inbred strains whose genomes have been either genotyped at high resolution or sequenced. To further investigate the genetics of NIHL, we report the first GWAS based on distortion product otoacoustic emission (DPOAE) measurements and the HMDP.

METHODS

A total of 102 strains (n = 635) from the HMDP were evaluated based on DPOAE suprathreshold amplitudes before and after noise exposure. DPOAE amplitude variation was set at 60 and 70 dB SPL of the primary tones for each frequency separately (8, 11.3, 16, 22.6, and 32 kHz). These values provided an indirect assessment of outer hair cell integrity. Six-week-old mice were exposed for 2 h to 10 kHz octave-band noise at 108 dB SPL. To perform local expression quantitative trait locus (eQTL) analysis, gene expression microarray profiles were generated using cochlear RNA from 64 hybrid mouse strains (n = 3 arrays per strain).

RESULTS

Several new loci were identified and positional candidate-genes associated with NIHL were prioritized, especially after noise exposure (1 locus at baseline and 5 loci after exposure). A total of 35 candidate genes in these 6 loci were identified with at least 1 probe whose expression was regulated by a significant cis-eQTL in the cochlea. After careful analysis of the candidate genes based on cochlear gene expression, 2 candidate genes were prioritized: Eya1 (baseline) and Efr3a (post-exposure).

DISCUSSION AND CONCLUSION

For the first time, an association analysis with correction for population structure was used to map several loci for hearing traits in inbred strains of mice based on DPOAE suprathreshold amplitudes before and after noise exposure. Our results identified a number of novel loci and candidate genes for susceptibility to NIHL, especially the Eya1 and Efr3a genes. Our findings validate the power of the HMDP for detecting NIHL susceptibility genes.

Is it necessary to perform occupational audiometric testing at 6-months of employment?

Introduction

Current Brazilian legislation requires that all workers exposed to noise are to be given an audiogram upon hiring, after 6 months of employment (first periodic test), and annually after the first periodic test. In other countries, the regulations of hearing conservation programs do not include the requirement for audiometric testing at 6 months of employment, but only annually. There is no evidence that the periodicity adopted by Brazilian legislation is the most appropriate.

Objective

The present study aimed to evaluate the first 3 occupational audiometric tests of workers exposed to noise.

Methods

Historical cohort study with cross-sectional analysis. Participants were all male metallurgy workers aged up to 40 years. The first 3 audiograms of each worker were analyzed: pre-employment audiometric test, periodic audiometric test 1, and periodic audiometric test 2. For each worker, mean frequency thresholds were calculated at 3, 4, and 6 kHz in the left and right ears for each test. Statistical analysis was performed using the nonparametric Wilcoxon test.

Results

A total of 988 workers were included. There was a significant difference in auditory thresholds between the pre-employment test and the 2 subsequent periodic tests for the right and left ears. There was no significant difference between Test1 and Test2 in either ear.

Conclusion

Given the lack of difference between the first 2 periodic tests, we believe that they could be merged into a single test, i.e., first periodic audiometric testing could be performed at 12 months of employment without compromising workers’ health.

Thorax necrotizing fasciitis following Bezold's abscess

Bezold's abscess is a rare complication of acute otitis media, but it should be recognized and aggressively treated. Otolaryngologists must be aware of this diagnosis, and multidisciplinary care should be provided as soon as possible.

Tympanic Membrane Retractions in patients with Williams Syndrome: A Controlled Study

Introduction  The role of elastin in tympanic retractions and chronic otitis media is not well established. Williams Syndrome (WS), a pathology related to a mutation in the elastin gene, could generate tympanic retractions. Objective  To compare the prevalence of tympanic retractions among patients with WS and controls. Methods  WS patients ( n  = 43 ears) and controls ( n  = 130 ears) were evaluated by digital otoscopic examination and the degree of tympanic membrane retraction was classified by 2 blinded experienced otolaryngologists. Results  The agreement rate between the evaluators was 71.1% for pars tensa and 65% for pars flaccida retraction ( p  < 0.001). The pars tensa and pars flaccida retractions are present in patients with WS after an adjusted residue of respectively - 2.8 and - 2.6 ( p  = 0.011 and p  = 0.022) compared with controls. Conclusions  Tympanic membrane retractions are not more common in the WS group when compared with controls.

The COVID-19 Pandemic and Planetary Health. A Critical Review of Epidemiology, Prevention, Clinical Characteristics and Treatments for Oral, Head and Neck Health Professionals. Do We Have a Roadmap?

Introduction  Coronavirus disease 19 (COVID-19) is potentially the greatest global public health crisis of this century. This disease emerged as an outbreak of pneumonia of unknown cause in Wuhan, the capital city of the Hubei province in China, in December 2019. Otolaryngologists, head and neck surgeons and dentists are at an increased risk of occupational disease. Objective  The present review summarizes currently published evidence of Covid-19 epidemiology, clinical characteristics, treatment and prevention. No proven effective treatments for this disease currently exist. Data Synthesis  COVID-19 started from a zoonotic transmission event associated with a large seafood market that also traded in live wild animals, and it soon became clear that efficient person-to-person transmission was also occurring. Symptoms are varied, and not all patients develop all of them. Conclusion  Social distancing seems to have been successful in several places in the world. However, this recommendation alone is not enough to contain the disease, and it is not a long-term solution. Large-scale testing by health professionals of representative samples of the population may give an estimate of the progression of the disease. Different treatments are under test and bring hope of a cure to the population. However, no current treatments (April 27, 2020) have been proven to be the key to success in the treatment of patients with COVID-19. Planetary health is a useful concept to understand the current drivers of this pandemic and to draw a roadmap for science and healthcare that may guide actions to fight economic depression and ensure a healthy recovery.

Effect of Noise Exposure on 1,382 Metallurgical Workers in Periodic Audiometric Evaluation: A Cohort Study

INTRODUCTION

Noise-induced hearing loss is the most preventable cause of auditory impairment. Periodic audiometric evaluations are essential to monitor the hearing health of noise-exposed workers.

OBJECTIVE

To compare the evolution of audiometric thresholds in the initial three evaluations at frequencies of 3, 4, and 6 kHz in groups of workers exposed or not to noise.

METHODS

In this historical cohort study, audiometric evaluations were obtained from male workers between 18 and 40 years of age at six different metallurgical companies in Brazil. The workers were separated into noise-exposed and non-noise-exposed groups. The mean thresholds for 3, 4, and 6 kHz were calculated for both ears at baseline and the first and second periodic evaluations. The non-parametric Wilcoxon test was used for statistical analysis.

RESULTS

A total of 1,382 metallurgical workers were evaluated (1,199 noise-exposed and 183 non-noise-exposed). There was a significant difference between baseline and the first periodic evaluation (right ear - effect size = 0.62; p = 0.0030 and left ear - effect size = 0.74; p = 0.0063) and between baseline and the second periodic evaluation (right ear - effect size = 0.85; p = 0.004 and left ear - effect size = 0.96; p = 0.0002). In the non-noise-exposed group, there was no difference between baseline and the first periodic evaluation (right ear - effect size = 0.18; p = 0.2703 and left ear - effect size = 0.12; p = 0.7907) and between baseline and the second periodic evaluation (right ear - effect size = 0.29; p = 0.4475 and left ear - effect size = 0.41; p = 0.6381).

CONCLUSION

In noise-exposed workers, there was a significant worsening of audiometric thresholds between baseline and the initial periodic evaluation, but there was no difference between the two post-baseline evaluations. This shows that noise exposure can quickly affect hearing, despite protective measures.

An update on COVID-19 for the otorhinolaryngologist - a Brazilian Association of Otolaryngology and Cervicofacial Surgery (ABORL-CCF) Position Statement

Introduction

We are facing a pandemic with a great impact worldwide, as a result of the rapid spread of the novel coronavirus (COVID-19). The medical community is still getting to know behavior of this virus and the consequences from a population point of view. All this knowledge is extremely dynamic, so some behaviors are still not well established. Otorhinolaryngologists have a central role in the management of this situation, in which they must assess the patient, avoid contamination to and by health professionals and other patients. Thus, the recommendations of the Brazilian Association of Otorhinolaryngology and Cervical-Facial Surgery (ABORL-CCF) have the main objective of reducing the spread of the new coronavirus during otorhinolaryngological care and assisting in the management of these patients.

Methods

Review of the main recommendations of national and international scientific societies, decisions by government agencies and class councils. The topics will be related to the general aspects of COVID-19, personal protective equipment, care in patient assistance, endoscopic exam routines and the management of sinonasal, otological and pediatric evaluations related to COVID-19.

Results

The use of personal protective equipment is considered crucial in routine ENT care. We recommend postponing appointments, exams and elective surgeries to reduce the spread of COVID-19. Similarly, we recommend changing routines in several areas of otolaryngology. Additionally, guidance is provided on the use of telemedicine resources during the pandemic period.

Conclusions

We are still at the beginning of the COVID-19 pandemic and scientific evidence is still scarce and incomplete, so these ABORL-CCF recommendations for otorhinolaryngologists may be updated based on new knowledge and the pattern of the new coronavirus spread.

Neurotology: definitions and evidence-based therapies - Results of the I Brazilian Forum of Neurotology

Introduction

Neurotology is a rapidly expanding field of knowledge. The study of the vestibular system has advanced so much that even basic definitions, such as the meaning of vestibular symptoms, have only recently been standardized.

Objective

To present a review of the main subjects of neurotology, including concepts, diagnosis and treatment of Neurotology, defining current scientific evidence to facilitate decision-making and to point out the most evidence-lacking areas to stimulate further new research.

Methods

This text is the result of the I Brazilian Forum of Neurotology, which brought together the foremost Brazilian researchers in this area for a literature review. In all, there will be three review papers to be published. This first review will address definitions and therapies, the second one will address diagnostic tools, and the third will define the main diseases diagnoses. Each author performed a bibliographic search in the LILACS, SciELO, PubMed and MEDLINE databases on a given subject. The text was then submitted to the other Forum participants for a period of 30 days for analysis. A special chapter, on the definition of vestibular symptoms, was translated by an official translation service, and equally submitted to the other stages of the process. There was then a in-person meeting in which all the texts were orally presented, and there was a discussion among the participants to define a consensual text for each chapter. The consensual texts were then submitted to a final review by four professors of neurotology disciplines from three Brazilian universities and finally concluded. Based on the full text, available on the website of the Brazilian Association of Otorhinolaryngology and Cervical-Facial Surgery, this summary version was written as a review article.

Result

The text presents the official translation into Portuguese of the definition of vestibular symptoms proposed by the Bárány Society and brings together the main scientific evidence for each of the main existing therapies for neurotological diseases.

Conclusion

This text rationally grouped the main topics of knowledge regarding the definitions and therapies of Neurotology, allowing the reader a broad view of the approach of neurotological patients based on scientific evidence and national experience, which should assist them in clinical decision-making, and show the most evidence-lacking topics to stimulate further study.

The Role of Magnetic Resonance Imaging of the Temporomandibular Joint to Investigate Tinnitus in Adults with Temporomandibular Joint Disorder: A Comparative Study

Introduction  The prevalence of tinnitus is higher in individuals with temporomandibular joint disorder (TMD) than in the general population. Magnetic resonance imaging (MRI) of the temporomandibular joint (TMJ) is the method of choice for investigation, and it has been hypothesized that specific MRI findings might be observed in TMD with comorbid tinnitus.

Objective  To comparatively describe MRI findings in patients with TMD with and without tinnitus, identifying the most common TMJ alterations and determining whether a correlation exists between severity of TMD and tinnitus.

Methods  A cross-sectional study of 53 adult patients with bilateral or unilateral TMD (30 with and 23 without tinnitus). The association between tinnitus and morphological aspects of TMD (changes in condylar morphology, articular eminence morphology, and disc morphology), disc displacement (with/without reduction), condylar translation, and intra-articular effusion was analyzed on MRI images.

Results  The mean patient age was 46.12 ± 16.1 years. Disc displacement was the most common finding in both groups (24 patients with tinnitus versus 15 without; p  = 0.043). Only the frequency of disc displacement with reduction was significantly different between groups.

Conclusion  Additional imaging techniques should be explored to detect specific aspects of the relationship between tinnitus and TMD.

Petroclival Meningiomas: Factors Determining the Choice of Approach

Objectives  To review a surgical series of petroclival meningiomas and the factors considered in the choice of approach. Design  Retrospective review. Setting  The study was conducted in a university hospital in southern Brazil. Participants  Twenty-two patients with petroclival meningioma originating from the upper two-thirds of the clivus medial to the fifth cranial nerve. Main Outcome Measures  Gross-total resection, mortality, major morbidity, new cranial nerve deficits and tumor progression or recurrence. Results  Retrosigmoid approach was used in tumors <3 cm and in those at or below the internal auditory meatus. Posterior petrosectomy was performed for tumors extending into the middle fossa. Gross-total resection was performed in 11 patients (50%). The mean follow-up time was 32 months (6-75 months). There were four cases of tumor progression or recurrence, which were treated with radiosurgery. Conclusions  Resection of petroclival meningiomas remains challenging. In most cases, the retrosigmoid approach was sufficient, without affecting the degree of tumor resection. Petrosal approaches were reserved for patients with tumor extension into the middle fossa.

Role of Neuropilin-1/Semaphorin-3A signaling in the functional and morphological integrity of the cochlea

Neuropilin-1 (Nrp1) encodes the transmembrane cellular receptor neuropilin-1, which is associated with cardiovascular and neuronal development and was within the peak SNP interval on chromosome 8 in our prior GWAS study on age-related hearing loss (ARHL) in mice. In this study, we generated and characterized an inner ear-specific Nrp1 conditional knockout (CKO) mouse line because Nrp1 constitutive knockouts are embryonic lethal. In situ hybridization demonstrated weak Nrp1 mRNA expression late in embryonic cochlear development, but increased expression in early postnatal stages when cochlear hair cell innervation patterns have been shown to mature. At postnatal day 5, Nrp1 CKO mice showed disorganized outer spiral bundles and enlarged microvessels of the stria vascularis (SV) but normal spiral ganglion cell (SGN) density and presynaptic ribbon body counts; however, we observed enlarged SV microvessels, reduced SGN density, and a reduction of presynaptic ribbons in the outer hair cell region of 4-month-old Nrp1 CKO mice. In addition, we demonstrated elevated hearing thresholds of the 2-month-old and 4-month-old Nrp1 CKO mice at frequencies ranging from 4 to 32kHz when compared to 2-month-old mice. These data suggest that conditional loss of Nrp1 in the inner ear leads to progressive hearing loss in mice. We also demonstrated that mice with a truncated variant of Nrp1 show cochlear axon guidance defects and that exogenous semaphorin-3A, a known neuropilin-1 receptor agonist, repels SGN axons in vitro. These data suggest that Neuropilin-1/Semaphorin-3A signaling may also serve a role in neuronal pathfinding in the developing cochlea. In summary, our results here support a model whereby Neuropilin-1/Semaphorin-3A signaling is critical for the functional and morphological integrity of the cochlea and that Nrp1 may play a role in ARHL.

Neuropilin-1 is a member of the neuropilin family acting as an essential cell surface receptor involved in semaphorin-dependent axon guidance and VEGF-dependent angiogenesis and lies within our previously identified ARHL GWAS interval. In this study, we investigated the role of Neuropilin-1/Semaphorin-3A signaling in the functional and morphological integrity of the cochlea, specifically the innervation and vascularization patterns. Detailed analyses of the cochleae of 4-month-old Nrp1 CKO mice showed abnormalities in ribbon synapses, innervation of the hair cells, and microvessels of the stria vascularis. We show also that Neuropilin-1/Semaphorin-3A signaling plays an important role in cochlear innervation.

The Crista Fenestra and Its Impact on the Surgical Approach to the Scala Tympani during Cochlear Implantation

Objective: The aim of this work was to describe the dimensions of the crista fenestra and determine its presence by means of high-resolution computed tomography (CT) for the purpose of cochlear implantation via the round window approach. Methods: A series of 10 adult human temporal bones underwent high-resolution CT scanning and were further dissected for microscopic study of the round window niche. Results: In all of the specimens, the round window membrane was fully visualized after the complete removal of bony overhangs. The crista fenestra was identified as a sharp bony crest located in the anterior and inferior borders of the niche; its area ranged from 0.28 to 0.80 mm2 (mean 0.51 ± 0.18). The proportion of the area occupied by the crista fenestra in the whole circumference of the round window ranged from 23 to 50% (mean 36%). We found a moderate positive correlation between the area of the niche and the dimensions of the crista fenestra (Spearman rho: 0.491). In every case, high-resolution CT scanning was unable to determine the presence of the crista fenestra. Conclusion: The crista fenestra occupies a variable but expressive area within the bony round window niche. Narrower round window niches tended to house smaller crests. The presence of the crista fenestra is an important obstacle to adequate access to the scala tympani. Nevertheless, a high-resolution CT scan provides no additional preoperative information with regard to its presence for the purpose of surgical access to the scala tympani via the round window niche.

Large-scale phenotyping of noise-induced hearing loss in 100 strains of mice

A cornerstone technique in the study of hearing is the Auditory Brainstem Response (ABR), an electrophysiologic technique that can be used as a quantitative measure of hearing function. Previous studies have published databases of baseline ABR thresholds for mouse strains, providing a valuable resource for the study of baseline hearing function and genetic mapping of hearing traits in mice. In this study, we further expand upon the existing literature by characterizing the baseline ABR characteristics of 100 inbred mouse strains, 47 of which are newly characterized for hearing function. We identify several distinct patterns of baseline hearing deficits and provide potential avenues for further investigation. Additionally, we characterize the sensitivity of the same 100 strains to noise exposure using permanent thresholds shifts, identifying several distinct patterns of noise-sensitivity. The resulting data provides a new resource for studying hearing loss and noise-sensitivity in mice.

Genome-wide association study identifies nox3 as a critical gene for susceptibility to noise-induced hearing loss

In the United States, roughly 10% of the population is exposed daily to hazardous levels of noise in the workplace. Twin studies estimate heritability for noise-induced hearing loss (NIHL) of approximately 36%, and strain specific variation in sensitivity has been demonstrated in mice. Based upon the difficulties inherent to the study of NIHL in humans, we have turned to the study of this complex trait in mice. We exposed 5 week-old mice from the Hybrid Mouse Diversity Panel (HMDP) to a 10 kHz octave band noise at 108 dB for 2 hours and assessed the permanent threshold shift 2 weeks post exposure using frequency specific stimuli. These data were then used in a genome-wide association study (GWAS) using the Efficient Mixed Model Analysis (EMMA) to control for population structure. In this manuscript we describe our GWAS, with an emphasis on a significant peak for susceptibility to NIHL on chromosome 17 within a haplotype block containing NADPH oxidase-3 (Nox3). Our peak was detected after an 8 kHz tone burst stimulus. Nox3 mutants and heterozygotes were then tested to validate our GWAS. The mutants and heterozygotes demonstrated a greater susceptibility to NIHL specifically at 8 kHz both on measures of distortion product otoacoustic emissions (DPOAE) and on auditory brainstem response (ABR). We demonstrate that this sensitivity resides within the synaptic ribbons of the cochlea in the mutant animals specifically at 8 kHz. Our work is the first GWAS for NIHL in mice and elucidates the power of our approach to identify tonotopic genetic susceptibility to NIHL.

Noise-induced hearing loss (NIHL) is the most common work-related disease in the world and the second cause of hearing loss. Although several candidate gene association studies for NIHL in humans have been conducted, each are underpowered, un-replicated, and account for only a fraction of the genetic risk. Buoyed by the prospects and successes of human association studies, several groups have proposed mouse genome-wide association studies. The environment can be carefully controlled, facilitating the study of complex traits like NIHL. In this manuscript, we describe, for the first time, an association analysis with correction for population structure for the mapping of several loci for susceptibility to NIHL in inbred strains of mice. We identify Nox3 as the associated gene for susceptibility to NIHL that the genetic susceptibility is frequency specific and that it occurs at the level of the cochlear synaptic ribbon.

Linear Acceleration Response Variation in Inbred Strains of Mice: The Requisite for Gene Discovery

Objectives:

(1) Evaluate gravity receptor function using vestibular evoked potentials (VsEPs) recordings in different strains of mice. (2) Indicate functional variation in VsEPs response parameters across strains for the Genome-Wide Association Study (GWAS) mapping of the vestibular system.

Methods:

Mice (6 weeks old) were anesthetized with ketamine 100 mg/kg and xylazine 10 mg/kg and were positioned supine with the head mount coupled and the cranium securely fastened to a mechanical shaker. Stimuli consisted of linear acceleration (17 pulses/s) applied to the cranium in the naso-occipital axis. The first (P1) and second (P2) positive and negative response peaks were measured as phenotypes. Mice were selected based on a combined set of classic inbred (CI) and recombinant inbred (RI) strains from the Hybrid Mouse Diversity Panel (HMDP). A total of 13 CI (C57BL/6J, FVB/NJ, Balb/cJ, C3H/HeJ, Balb/cByJ, AKR/J, 129x1/SvJ, A/J, DBA/2J, SJL/J, CBA/J, SEA/GnJ, and NOD/ShiLtJ) and 10 RI (BXA14/PgnJ, BXD84/RwwJ, BXH19/TyJ, BXH22/KccJ, BXH9/TyJ, BXH10/TyJ, BXA14/PgnJ, BXA4/PgnJ, BXA16/PgnJ, and CXB9/HiAJ) were evaluated with an average of 2.7 mice/strain.

Results:

A wide range of phenotypic responses was observed. The mean threshold (–8.73 ± 5.1 dB re: 1 g/ms) and P2-N2 amplitude at +6 dB re: 1 g/ms (0.682 ± 0.51 mV) both demonstrated statistical significant variation (analysis of variance) in VsEP thresholds ( P = .008) and P2-N2 amplitude ( P = .001).

Conclusions:

These data demonstrate significant variation in VsEP response parameters across strains, strongly suggesting the hypothesis that there exists functional variation of vestibular function among strains of mice and the genetic determinants of such variation can be mapped using GWAS.

Cocleostomia transcanal: resultados em longo prazo de um estudo de coorte

The combined approach technique (CAT) is a variation of the classical the mastoidectomy-posterior tympanotomy technique (MPTA) that combines a transcanal approach to cochleostomy with a reduced posterior tympanotomy for insertion of electrodes.

Aim

To compare and evaluate long-term safety and effectiveness outcomes obtained with the CAT and with MPTA approach in patients submitted to cochlear implant (CI) surgery. Design: series study.

Methods

Patients who underwent CI using CAT or MPTA at a Brazilian center were followed in a cohort study. Main outcomes were complications, audiometric performance and radiological evaluation of electrode position.

Results

Fourty-four patients were implanted using CAT and 31 MPTA. There were no cases of facial nerve paralysis, mastoiditis, cholesteatoma or cerebrospinal fluid leaks after 3.4±1.0 years. Radiological evaluation of electrode position revealed that the median number of electrodes outside the cochlea was 0 in CAT and 3 in MPTA groups (p < 0.001). There were no differences between both surgical approaches in terms of mean pure-tone thresholds with CI at all frequencies.

Conclusion

Long-term follow-up data showed that the transcanal route to cochleostomy, combined with a reduced posterior tympanotomy, is a safe alternative approach in cochlear implant surgery, with no related major complications and fewer cases of electrode migration when compared with the MPTA. These findings encourage the use of the transcanal route to cochleostomy as an alternative approach option.

Transcanal cochleostomy in cochlear implantation: experience with 50 cases

The traditional access route for cochlear implantation was initially proposed by William House in 1961. Alternatives to this surgical approach have been suggested by many authors. The combined approach technique (CAT) is a variation of the traditional mastoidectomy-posterior tympanotomy method, which uses a transcanal approach to cochleostomy combined with a small mastoidectomy and an equally small posterior tympanotomy for the insertion of electrodes. This paper presents a detailed description of this alternative procedure, reporting our experience with 50 cases, and adds our contribution regarding possible advantages and implications of using a transcanal cochleostomy. The subjects had profound and severe bilateral hearing loss and had not benefited from external hearing aids. They underwent cochlear implantation at Hospital de Clinicas de Porto Alegre from May 2003. The median follow-up was 29 months. All cases were successfully implanted using CAT. No major complications, such as facial paralysis or paresis, meningitis, cholesteatoma, or cerebrospinal fluid leaks, were observed in any patient. The CAT is a safe and efficient variation of cochlear implantation surgery, which is especially appropriate if cochlear calcification or malformations are present, or whenever cochleostomy has to be performed anteriorly, and when the position of the facial nerve prevents an adequate posterior tympanotomy.

Effectiveness of hypopharyngeal packing during nasal and sinus surgery in the prevention of PONV

OBJECTIVE

Evaluate the hypopharyngeal packing effectiveness on prevention of postoperative nausea and vomiting (PONV) in nasal surgery.

STUDY DESIGN AND SETTING

A randomized clinical trial was conducted from July 2004 to October 2005. The intervention group was submitted to hypopharyngeal packing after orotracheal tube placement. The control group had no hypopharyngeal packing. Occurrence of nausea, vomiting, use of antiemetic drugs, and throat pain were checked blindly on recovery period.

RESULTS

One hundred forty-four patients were included in the study. There was no difference related to postoperative nausea (RR 1.34; CI 0.72-2.48), vomiting (RR 0.52; CI 0.19-1.47), use of antiemetic drugs (RR 1.54; CI 0.80-2.95), and throat pain (RR 0.91; 0.62-1.34) between both groups. A beta error could not be excluded.

CONCLUSION

Results suggest there is no benefit in hypopharyngeal packing on PONV prevention in nasal surgery. New studies with a greater number of patients should be carried out in order to confirm these results.

Proliferative diabetic retinopathy is associated with microalbuminuria in patients with type 2 diabetes

Diabetic retinopathy is one of the leading causes of blindness in working-age individuals. Diabetic patients with proteinuria or those on dialysis usually present severe forms of diabetic retinopathy, but the association of diabetic retinopathy with early stages of diabetic nephropathy has not been entirely established. A cross-sectional study was conducted on 1214 type 2 diabetic patients to determine whether microalbuminuria is associated with proliferative diabetic retinopathy in these patients. Patients were evaluated by direct and indirect ophthalmoscopy and grouped according to the presence or absence of proliferative diabetic retinopathy. The agreement of diabetic retinopathy classification performed by ophthalmoscopy and by stereoscopic color fundus photographs was 95.1% (kappa = 0.735; P < 0.001). Demographic information, smoking history, anthropometric and blood pressure measurements, glycemic and lipid profile, and urinary albumin were evaluated. On multiple regression analysis, diabetic nephropathy (OR = 5.18, 95% CI = 2.91-9.22, P < 0.001), insulin use (OR = 2.52, 95% CI = 1.47-4.31, P = 0.001) and diabetes duration (OR = 1.04, 95% CI = 1.01-1.07, P = 0.011) were positively associated with proliferative diabetic retinopathy, and body mass index (OR = 0.90, 95% CI = 0.86-0.96, P < 0.001) was negatively associated with it. When patients with macroalbuminuria and on dialysis were excluded, microalbuminuria (OR = 3.3, 95% CI = 1.56-6.98, P = 0.002) remained associated with proliferative diabetic retinopathy. Therefore, type 2 diabetic patients with proliferative diabetic retinopathy more often presented renal involvement, including urinary albumin excretion within the microalbuminuria range. Therefore, all patients with proliferative diabetic retinopathy should undergo an evaluation of renal function including urinary albumin measurements.

[Low-dose aspirin in patients with diabete melitus: risks and benefits regarding macro and microvascular complications]

Aspirin is recommended as cardiovascular disease prevention in patients with diabetes mellitus. Due to the increased risk of bleeding and because of the hypothesis that there could be a worsening of microvascular complications related to aspirin, there has been observed an important underutilization of the drug. However, it is now known that aspirin is not associated with a deleterious effect on diabetic retinopathy and there is evidence indicating that it also does not affect renal function with usual doses (150 mg/d). On the other hand, higher doses may prove necessary, since recent data suggest that diabetic patients present the so called "aspirin resistance". The mechanisms of this resistance are not yet fully understood, being probably related to an abnormal intrinsic platelet activity. The employment of alternative antiplatelet strategies or the administration of higher aspirin doses (150-300 mg/d) should be better evaluated regarding effective cardiovascular disease prevention in diabetes as well as the possible effects on microvascular complications.

Use of a contact lens telescopic system in low vision patients

This study was designed to evaluate the effectiveness of a contact lens telescopic system in patients diagnosed with low vision. Fifteen white patients (mean age 60.7 years) with visual acuity between 20/60 and 20/400 (mean 20/245) were evaluated using first a conventional telescope and subsequently a contact lens telescope (CLT). Evaluation parameters were visual acuity, amplitude of visual field, and patients' satisfaction with the systems. The mean final visual acuity attained with both systems was 20/105. No differences in visual acuity between the two systems were detected. However, the visual field was significantly different with each system. Mean visual field with the conventional telescope was 22 degrees, whereas with the CLT it was 52.1 degrees. This corresponds to a reduction of 78.2% in the field of view with the conventional telescope and of 49.5% with the CLT. Therefore, the CLT was found to provide a field of view that is 136% as great as the one provided by the conventional telescope. Younger patients are specially enthusiastic about the CLT because of its improved cosmetic appearance and visual field as compared to traditional telescopes. Aged patients tend to have more difficulty in accepting and using contact lenses daily.

Visual-evoked potentials: assessment of retrobulbar and peribulbar anesthesia

PURPOSE

To assess the effects of retrobulbar and peribulbar anesthesia on nerve function as detected by visual-evoked potentials (VEPs).

SETTING

University hospital in southern Brazil.

METHODS

In a prospective study, 7 patients had peribulbar anesthesia and 9 had retrobulbar anesthesia for extracapsular cataract extraction. Visual-evoked potentials with pattern reversal and flash stimulation were performed at least 1 month before and 1 month after surgery. Study participants did not have ocular pathology other than cataract. The Lens Classification System III was used to grade the opacities before surgery.

RESULTS

No significant difference was found between preoperative and postoperative evaluations in VEP flash and pattern-reversal amplitude and latency in either group (P >.05). Postoperative amplitude and latency was not significantly different between the peribulbar and retrobulbar groups. Two cases in the peribulbar group had altered wave morphology without clinical manifestation postoperatively. All patients had a final best spectacle-corrected visual acuity of 20/20.

CONCLUSION

Block anesthetic procedures were safely used in cataract surgery, with no clinical sequelae to the optic nerve.