Psychological factors and long-term tinnitus handicap in vestibular schwannoma patients after retrosigmoid microsurgery - a cross-sectional study.

OBJECTIVE: This study aimed to investigate the connection between psychological factors and postoperative tinnitus in vestibular schwannoma (VS) patients following retrosigmoid microsurgery. DESIGN: Cross-sectional study. STUDY SAMPLE: Ninety-three VS patients participated, completing questionnaires on demographics, tinnitus severity (THI-12), personality traits (TIPI-G), dizziness impact (DHI), perceived health benefits (GBI), somatisation tendencies (SOMS-2), and psychological distress (HADS-D). Our analysis involved Mann-Whitney U-tests, Spearman's rank-order correlations, and false discovery rate correction. RESULTS: Most participants reported postoperative tinnitus (77/93), with 41 experiencing it preoperatively. Emotional stability correlated negatively with tinnitus presence, while tinnitus severity was associated with emotional distress. Preoperative somatisation tendencies were also positively linked to tinnitus severity. Postoperative Tinnitus was further linked to reduced perceived health benefits and increased anxiety and depression levels. Notably, age and gender showed no significant associations. CONCLUSION: This study uncovers the interplay between postoperative tinnitus and psychological factors in VS patients, highlighting emotional and cognitive dimensions. Tailored psychological interventions addressing tinnitus's psychosomatic impact may enhance patients quality of life.

[Pulmonary phenotypes of inborn errors of metabolism]. / Manifestations pulmonaires des maladies héréditaires du métabolisme.

Inborn metabolic diseases or inborn errors of metabolism comprise a large number of rare and heterogeneous genetic diseases categorized in several subgroups depending on their pathophysiologic mechanisms. In this review, we focus on different metabolic diseases with respiratory symptoms in adults: lysosomal glycosphingolipidoses such as acid sphingomyelinase deficiency (Niemann-Pick types A and B disease), Gaucher, Fabry, Pompe diseases and mucopolysaccharidoses in general. We also address classical homocystinuria, which is a monogenic vascular disease, Hermansky-Pudlak syndrome, which is associated with disorders in the lysosomal-related-organelles, and lysinuric protein intolerance, which is due to an amino-acid transporter defect. Presentation and prognosis of these diseases are highly heterogeneous, and respiratory impairment may be central and prognostic. Many are primarily pediatric, and diagnoses are often delivered during childhood. Improved pediatric management has enabled better prognosis and new phenotype of the diseases in the adulthood. Some others can be diagnosed during adulthood. While some diseases call for specific, specialized treatment, all necessitate systematic multidisciplinary management. It is of paramount importance that a pneumologist be familiar with these phenotypes, most of which can benefit from early diagnosis and early therapeutic management with dedicated innovative treatments.

Estimating the surgical backlog from the COVID-19 lockdown in South Africa: A retrospective analysis of six government hospitals.

BACKGROUND: The COVID-19 pandemic reached South Africa (SA) in March 2020. A national lockdown began on 27 March 2020, and health facilities reduced non-essential activity, including many surgical services. PRIMARY OBJECTIVE: to estimate the COVID-19 surgical backlog in Western Cape Province, SA, by comparing 2019 and 2020 general surgery operative volume and proportion at six district and regional hospitals. SECONDARY OBJECTIVE: to compare the operative volume of appendicectomy, laparoscopic cholecystectomy, cancer and trauma between the 2 years. METHODS: This was a retrospective study of general surgery operations from six SA government hospitals in the Western Cape. Data were obtained from electronic operative databases or operative theatre logbooks from 1 April to 31 July 2019 and 1 April to 31 July 2020. RESULTS: Total general surgery operations decreased by 44% between 2019 (n=3 247) and 2020 (n=1 810) (p<0.001). Elective operations decreased by 74% (n=1 379 v. n=362; p<0.001), and one common elective procedure, laparoscopic cholecystectomy, decreased by 68% (p<0.001). Emergency operations decreased by 22% (n=1 868 v. n=1 448; p<0.001) and trauma operations by 42% (n=325 v. n=190; p<0.001). However, non-trauma emergency operations such as appendicectomy and cancer did not decrease. The surgical backlog for elective operations after 4 months from these six hospitals is 1 017 cases, which will take between 4 and 14 months to address if each hospital can do one additional operation per weekday. CONCLUSIONS: The COVID-19 pandemic has created large backlogs of elective operations that will need to be addressed urgently. Clear and structured guidelines need to be developed in order to streamline the reintroduction of full surgical healthcare services as SA slowly recovers from this unprecedented pandemic.

Validation of the Hamilton Program for Schizophrenia Voices Questionnaire: Associations with emotional distress and wellbeing, and invariance across diagnosis and sex.

BACKGROUND: Voice-hearing is a transdiagnostic experience with evident negative effects on patients. Good quality measurement is needed to further elucidate the nature, impact and treatment of voice-hearing experiences across patient groups. The Hamilton Program for Schizophrenia Voices Questionnaire (HPSVQ) is a brief self-report measure which requires further psychometric evaluation. METHODS: Using data from a transdiagnostic sample of 401 adult UK patients, the fit of a conceptual HPSVQ measurement model, proposing a separation between physical and emotional voice-hearing characteristics, was tested. A structural model was examined to test associations between voice-hearing, general emotional distress (depression, anxiety, stress) and wellbeing. The invariance of model parameters was examined across diagnosis and sex. RESULTS: The final measurement model comprised two factors named 'voice severity' and 'voice-related distress'. The former comprised mainly physical voice characteristics and the latter mainly distress and other negative impacts. Structural model results supported voice-related distress as mediating the associations between voice severity and emotional distress and wellbeing. Model parameters were invariant across psychosis versus non-psychosis diagnosis and partially invariant across sex. Females experienced more severe and distressing voices and a more direct association between voice severity and general anxiety was evident. CONCLUSIONS: The HPSVQ is a useful self-report measure of voice-hearing with some scope for further exploration and refinement. Voice-related distress appears a key mechanism by which voice severity predicts general distress and wellbeing. Whilst our data broadly support interventions targeting voice-related distress for all patients, females may benefit especially from interventions targeting voice severity and strategies for responding.

[Hearing classification in patients with vestibular schwannoma using German-language test procedures]. / Hörklassen bei Patienten mit Vestibularisschwannom bei Verwendung deutschsprachiger Testverfahren.

BACKGROUND: Hearing function in patients with vestibular schwannoma is often classified according to the Gardner and Robertson (1988) or the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS, 1995) systems. These classification systems are based on English-language test procedures, there is no German-language equivalent. The aim of the study was to investigate the influence of various target parameters on hearing classification and to derive a recommendation for the use of German-language test methods. MATERIALS AND METHODS: The rules for speech audiometry based on English-language test procedures were applied to German speech test materials. In 91 patients with vestibular schwannoma, pure tone hearing thresholds, speech recognition thresholds, and speech discrimination at different sound pressure levels were measured. The patients were categorized according to the Gardner and Robertson and AAO-HNS classifications. RESULTS: In both the Gardner-Robertson and the AAO-HNS classifications, the number of patients in the hearing classes with serviceable hearing function (measured as Pure Tone Average across three (3PTA) or four (4PTA) frequencies) was highest when using the 3PTA0,5;1;2 kHz condition, followed by 4PTA0,5;1;2;3 kHz, 4PTA0,5;1;2;4 kHz, and 4PTA0,5;1;2;"3"kHz. If maximum word recognition score (WRSmax) was used instead of word recognition 40 dB above the sensation level (WRS40SL), more patients were classified into the hearing classes with serviceable hearing function, irrespective of the mean pure tone hearing threshold. CONCLUSION: The Gardner-Robertson and AAO-HNS classifications can be used in German-speaking settings. The Freiburg monosyllabic test can be used to determine speech discrimination scores or maximum word recognition.

Management of transmodiolar and transmacular cochleovestibular schwannomas with and without cochlear implantation.

INTRODUCTION: Hearing rehabilitation with cochlear implants has attracted increasing interest also for patients with cochleovestibular schwannoma. The authors report their experience with the surgical management of tumors with rare transmodiolar or transmacular extension and outcomes after cochlear implantation (CI). METHODS: This retrospective case series included nine patients with either primary intralabyrinthine tumors or secondary invasion of the inner ear from the internal auditory canal. The primary endpoint with CI, performed in six patients, was word recognition score at 65 dB SPL (sound pressure level). Secondary endpoints were intra- and postoperative electrophysiological parameters, impedance measures, the presence of a wave V in the electrically evoked (via the CI) auditory brainstem responses, the specifics of postoperative CI programming, and adverse events. RESULTS: Hearing rehabilitation with CI in cases of transmodiolar tumor growth could be achieved only with incomplete tumor removal, whereas tumors with transmacular growth could be completely removed. All six patients with CI had good word recognition scores for numbers in quiet conditions (80-100% at 65 dB SPL, not later than 6 to 12 months post CI activation). Four of these six patients achieved good to very good results for monosyllabic words within 1-36 months (65-85% at 65 dB SPL). The two other patients, however, had low scores for monosyllables at 6 months (25 and 15% at 65 dB SPL, respectively) with worsening of results thereafter. CONCLUSIONS: Cochleovestibular schwannomas with transmodiolar and transmacular extension represent a rare entity with specific management requirements. Hearing rehabilitation with CI is a principal option in these patients.

[Management of transmodiolar and transmacular cochleovestibular schwannomas with and without cochlear implantation. German version]. / Management transmodiolärer und transmakulärer Vestibularis- und Cochlearisschwannome mit und ohne Cochleaimplantation.

INTRODUCTION: Hearing rehabilitation with cochlear implants has attracted increasing interest also for patients with cochleovestibular schwannoma. The authors report their experience with the surgical management of tumors with rare transmodiolar or transmacular extension and outcomes after cochlear implantation (CI). METHODS: This retrospective case series included nine patients with either primary intralabyrinthine tumors or secondary invasion of the inner ear from the internal auditory canal. The primary endpoint with CI, performed in six patients, was word recognition score at 65 dB SPL (sound pressure level). Secondary endpoints were intra- and postoperative electrophysiological parameters, impedance measures, the presence of a wave V in the electrically evoked (via the CI) auditory brainstem responses, the specifics of postoperative CI programming, and adverse events. RESULTS: Hearing rehabilitation with CI in cases of transmodiolar tumor growth could be achieved only with incomplete tumor removal, whereas tumors with transmacular growth could be completely removed. All six patients with CI had good word recognition scores for numbers in quiet conditions (80-100% at 65 dB SPL, not later than 6 to 12 months post CI activation). Four of these six patients achieved good to very good results for monosyllabic words within 1-36 months (65-85% at 65 dB SPL). The two other patients, however, had low scores for monosyllables at 6 months (25 and 15% at 65 dB SPL, respectively) with worsening of results thereafter. CONCLUSIONS: Cochleovestibular schwannomas with transmodiolar and transmacular extension represent a rare entity with specific management requirements. Hearing rehabilitation with CI is a principal option in these patients.

50 Shades of Red: The Predictive Value of Closed Suction Drains for the Detection of Postoperative Bleeding in Breast Surgery.

BACKGROUND: While closed suction drains (CSDs) are still frequently employed in clinical practice, the supporting evidence is limited with some studies demonstrating a failure of routine CSD use in preventing hematoma or seroma. Nonetheless, CSD quantity and quality fluid assessment is still appreciated by clinicians to detect postoperative bleeding. This study investigates the value of routine CSD use, in breast surgery, to predict postoperative bleeding. METHODS: A retrospective, intra-individual analysis, of CSD fluid volumes between the hematoma side and the unaffected contralateral breast, was undertaken in patients (n = 20) with unilateral postoperative bleeding following bilateral breast surgery (2003-2018). Statistical analysis was undertaken to establish a minimum cutoff fluid volume that might assist in the detection of postoperative bleeding. To determine the usefulness of quality assessment of CSD fluid output by visual inspection, surgeons (n = 56) prospectively matched six eligible hemoglobin concentrations corresponding to pre-filled CSDs. RESULTS: Statistical analysis did not yield a clinically reliable cutoff fluid volume indicating postoperative bleeding. All six eligible hemoglobin concentrations were completely successfully matched to pre-filled CSDs by 30.4% (17/56) of surgeons. CONCLUSIONS: This study questions the significance of routine CSD use to assist in the decision-making process to return to the theater and address postoperative bleeding. Quantity as well as quality analysis of CSD fluid output failed the reliability and diagnostic validity tests. Hemoglobin measurements in drain fluid specimens via blood gas analysis might contribute to the detection of postoperative bleeding. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A coloring-book approach to finding coordination sequences.

An elementary method is described for finding the coordination sequences for a tiling, based on coloring the underlying graph. The first application is to the two kinds of vertices (tetravalent and trivalent) in the Cairo (or dual-32.4.3.4) tiling. The coordination sequence for a tetravalent vertex turns out, surprisingly, to be 1, 4, 8, 12, 16, …, the same as for a vertex in the familiar square (or 44) tiling. The authors thought that such a simple fact should have a simple proof, and this article is the result. The method is also used to obtain coordination sequences for the 32.4.3.4, 3.4.6.4, 4.82, 3.122 and 34.6 uniform tilings, and the snub-632 tiling. In several cases the results provide proofs for previously conjectured formulas.

Case report: A fatal case of cryptococcosis in an immunocompetent patient due to Cryptococcus deuterogattii (AFLP6/VGII).

INTRODUCTION: Cryptococcosis in immunocompetent adults is a rare disease in Europe, mostly induced by members of the Cryptococcus gattii species complex. The diagnosis can be challenging due to its rarity, unspecific symptoms and long symptomless latency. CASE PRESENTATION: A 49-year-old woman with a three weeks history of headache was admitted to the hospital due to discrete ataxia and impaired vision. Cranial magnetic resonance imaging (MRI) showed a contrast-enhancing mass in the cerebellum. Further investigations detected a slight leukocytosis and a single subpleural nodule in the right inferior lung lobe. The cerebral lesion was surgically removed, and a direct frozen section only showed an unspecific inflammation. In the course of her admission she developed non-treatable cerebral edema and died ten days after surgical intervention. Histopathological examination of the surgical specimen and postmortem evaluation of the lung and the cerebrum demonstrated fungal elements. Molecular identification of the fungal elements in formalin-fixed paraffin-embedded tissue lead to the diagnosis of cryptococcosis induced by C. gattii sensu lato. Molecular genetic analysis identified the involved cryptococcal species as genotype AFLP6/VGII, recently described as Cryptococcus deuterogattii, which is known to be endemic to the west-coast of Canada and the USA. Additional heteroanamnestic information revealed that she had spent her holidays on Vancouver Island, Canada, two years before disease onset, indicating that infection during this stay seems to be plausible. CONCLUSION: Cryptococcosis due to C. deuterogattii is a rarely encountered fungal disease in Europe, not particularly associated with immunodeficiency, and infection is likely to be contracted in endemic areas. Due to its rarity, long symptomless latency, unspecific symptoms and misleading radiological features the diagnosis can be challenging. Physicians need to be aware of this differential diagnosis in immunocompetent patients, as early adequate therapy can be lifesaving.

Vasopressor support vs. liberal fluid administration in deep inferior epigastric perforator (DIEP) free flap breast reconstruction - a randomized controlled trial.

BACKGROUND: Perioperatively, patients' hemodynamics are modulated predominantly by intravenous fluid administration and vasoactive pharmacological support. Vasopressor agents are suspected to be detrimental on free flap survival by the cause of vasoconstriction of the pedicle with consecutive reduced overall flap perfusion and by aggravation of flap dissection. OBJECTIVE: A novel, standardized fluid restrictive perioperative hemodynamic management was assessed for its feasibility in clinical practice in free flap patients undergoing breast reconstruction. METHODS: Patients were randomized to two perioperative regimens with different fluid and vasopressor limits. The primary endpoint regarded flap survival. Secondary endpoints included surgery times, time of patient ambulation and length of hospital stay. RESULTS: There was one total flap failure with liberal fluid administration (LFA). No total or partial flap failure was noted in the fluid restrictive regimen with norepinephrine administration up to 0.04µg/kg/min (FRV). No delay regarding operation time (p = 0.217), patient mobilization (p = 0.550) or hospital discharge (p = 0.662) was registered in the FRV study subpopulation compared to LFA. CONCLUSIONS: The results of this prospective interventional trial could not detect any negative impact of vasopressors, neither for the primary endpoint of flap survival nor for the overall patient outcome. The fear of vasopressor associated flap complications has led to a traditional liberal fluid administration, which failed to demonstrate any benefits when compared to a fluid restrictive vasopressor strategy.

Preoperative determination of nerve of origin in patients with vestibular schwannoma.

BACKGROUND: Vestibular schwannoma (VS) is a benign tumor that develops in the internal auditory canal and the cerebellopontine angle, potentially diminishing hearing or balance. Most VS tumors arise from one of two vestibular branches: the superior or inferior vestibular nerve. Determining the specific nerve of origin could improve patient management in terms of preoperative counseling, treatment selection, and surgical decision-making and planning. The aim of this study was to introduce a novel scoring system that was designed to determine the nerve of origin. METHODS: The nerve of origin was predicted based on video head impulse assessments of all semicircular channels, together with cervical/ocular vestibular-evoked myogenic potential tests. The acquired data were entered into a scoring system developed to allocate the tumor origin. Finally, the nerve of origin was definitively determined intraoperatively. RESULTS: The novel scoring system was applied to five consecutive patients undergoing surgical VS treatment. In one case, no determination was possible. In all other cases, the preoperatively predicted tumor origin was the same as the origin determined during surgery. CONCLUSION: The scoring system predicts the nerve of origin and will be evaluated in a larger prospective cohort study of VS patients in the near future.

[Preoperative determination of nerve of origin in patients with vestibular schwannoma. German version]. / Präoperative Bestimmung des Ursprungsnervs von Vestibularisschwannomen.

BACKGROUND: Vestibular schwannoma (VS) is a benign tumor that develops in the internal auditory canal and the cerebellopontine angle, potentially diminishing hearing or balance. Most VS tumors arise from one of two vestibular branches: the superior or inferior vestibular nerve. Determining the specific nerve of origin could improve patient management in terms of preoperative counseling, treatment selection, and surgical decision-making and planning. The aim of this study was to introduce a novel scoring system that was designed to determine the nerve of origin. METHODS: The nerve of origin was predicted based on video head impulse assessments of all semicircular channels, together with cervical/ocular vestibular-evoked myogenic potential tests. The acquired data were entered into a scoring system developed to allocate the tumor origin. Finally, the nerve of origin was definitively determined intraoperatively. RESULTS: The novel scoring system was applied to 5 consecutive patients undergoing surgical VS treatment. In one case, no determination was possible. In all other cases, the preoperatively predicted tumor origin was the same as the origin determined during surgery. CONCLUSION: The scoring system predicts the nerve of origin and will be evaluated in a larger prospective cohort study of VS patients in the near future.

[Neuroprotective medication in vestibular schwannoma surgery]. / Medikamentöse Neuroprotektion in der Vestibularisschwannomchirurgie.

BACKGROUND: Except for glucocorticoids there is a lack of neuroprotective medication in neurosurgical interventions. OBJECTIVE: An overview of clinical trials investigating administration of the calcium antagonist nimodipine and hydroxyethyl starch (HES) in vestibular schwannoma (VS) surgery is given. Basic research is addressed and potential neuroprotective effect mechanisms are discussed, as are perspectives for application of the concept to other types of surgery with a risk postoperative impairment of nerve function. MATERIALS AND METHODS: A selective PubMed search was performed and all 10 clinical trials corresponding to the search criteria were included. RESULTS: Four trials with an intraoperative start of the medication showed a positive effect for the preservation of facial nerve function and hearing preservation. A pilot study showed superiority of prophylactic treatment over intraoperative application. There were no significant results in a prospective multicenter phase III trial. After 1 year, postoperative facial nerve preservation rates were excellent in both groups. However, the risk of hearing loss was twice as high in the control group. A combined analysis of the phase III trial with its pilot study showed significant results for better hearing preservation rates in the treatment group (probably by increasing the case load). CONCLUSION: Prophylactic nimodipine can be recommended in VS surgery in patients with good preoperative hearing. The effect mechanisms of nimodipine and modifications to prophylaxis should be clarified in basic research.

Intralabyrinthine schwannomas : Surgical management and hearing rehabilitation with cochlear implants.

Intralabyrinthine schwannomas (ILS) are a rare differential diagnosis of sudden hearing loss and vertigo. In an own case series of 12 patients, 6 tumors showed an intracochlear, 3 an intravestibular, 1 a transmodiolar including the cerebellopontine angle (CPA), 1a transotic including the CPA, and 1 a multilocular location. The tumors were removed surgically in 9 patients, whereas 3 patients decided for a "wait-and-test-and-scan" strategy. Of the surgical patients, 3 underwent labyrinthectomy and cochlear implant (CI) surgery in a single-stage procedure; 1 patient had extended cochleostomy with CI surgery; 3 underwent partial or subtotal cochleoectomy, with partial cochlear reconstruction and CI surgery (n = 1) or implantation of electrode dummies for possible later CI after repeated MRI follow-up (n = 2); and in 2 patients, the tumors of the internal auditory canal and cerebellopontine angle exhibiting transmodiolar or transmacular growth were removed by combined translabyrinthine-transotic resection. For the intracochlear tumors, vestibular function could mostly be preserved after surgery. In all cases with CI surgery, hearing rehabilitation was successful, although speech discrimination was limited for the case with subtotal cochleoectomy. Surgical removal of intracochlear schwannomas via partial or subtotal cochleoectomy is, in principle, possible with preservation of vestibular function. In the authors' opinion, radiotherapy of ILS is only indicated in isolated cases. Cochlear implantation during or after tumor resection (i. e., as synchronous or staged surgeries) is an option for hearing rehabilitation in cartain cases and represents a therapeutic approach in contrast to a "wait-and-test-and-scan" strategy.

Malignization of a vestibular schwannoma 13 years after radiation therapy.

This article presents a case of malignant transformation of vestibular schwannoma 13 years after stereotactic radiation therapy, which lead to an acute life-threatening condition. Although the observation is currently only based on case reports, an increasing number of these support the hypothesis that there is a relevant risk of malignant transformation in the long-term course of previously irradiated vestibular schwannomas. Therefore, long-term MRI follow-up should be considered.

[Intralabyrinthine schwannomas : Surgical management and hearing rehabilitation with cochlear implants. German version]. / Intralabyrinthäre Schwannome : Chirurgisches Management und Hörrehabilitation mit Cochleaimplantaten.

Intralabyrinthine schwannomas (ILS) are a rare differential diagnosis of sudden hearing loss and vertigo. In an own case series of 12 patients, 6 tumors showed an intracochlear, 3 an intravestibular, 1 a transmodiolar including the cerebello-pontine angle (CPA), 1 a transotic including the CPA and 1 a multilocular location. The tumors were removed surgically in 9 patients, whereas 3 patients opted for a "wait-and-test-and-scan" strategy. Of the surgical patients, 3 underwent labyrinthectomy and cochlear implant (CI) surgery in a single stage procedure; 1 patient received extended cochleostomy with CI surgery; 3 underwent partial or subtotal cochleoectomy, with partial cochlear reconstruction and CI surgery (n = 1) or implantation of electrode dummies for possible later CI following repeated MRI follow-up (n = 2); and in 2 patients, the tumors of the internal auditory canal and cerebellopontile angle exhibiting transmodiolar or transmacular growth were removed by combined translabyrinthine-transotic resection. For the intracochlear tumors, vestibular function could mostly be preserved after surgery. In all cases with CI surgery, hearing rehabilitation was successful, although speech discrimination was limited for the case with subtotal cochleoectomy. Surgical removal of intracochlear schwannomas via partial or subtotal cochleoectomy is, in principle, possible with preservation of vestibular function. In the authors' opinion, radiotherapy of ILS is only indicated in isolated cases. Provided performed early enough, cochlear implantation after surgical removal of ILS is an option for auditory rehabilitation, thus representing-in contrast to the "wait-and-test-and-scan" strategy-a therapeutic approach.

[Intraoperative monitoring of the facial nerve : Vestibular schwannoma surgery]. / Intraoperative Funktionsüberwachung des N. facialis : Operationen an Vestibularisschwannomen.

BACKGROUND: In vestibular schwannoma surgery, facial nerve injury with consecutive functional impairment is one of the most important complications. Intraoperative monitoring of facial nerve function has been developed in order to avoid this complication. OBJECTIVE: Which methods for intraoperative monitoring have been developed? Which methods are in use today and what can they achieve in modern vestibular schwannoma surgery? MATERIAL AND METHODS: This article provides an evaluation and summary of the literature, as well as a discussion of the methods and their ability to achieve the goals of intraoperative monitoring. RESULTS: Intraoperative functional monitoring aims to identify and map the facial nerve in the surgical field during surgery. It also aims to identify potentially damaging events and allow for intraoperative prognosis of functional outcome. Available methods are direct electrical stimulation, free-running electromyogram (EMG), facial nerve evoked potentials, and processed EMG. CONCLUSION: Identification and mapping of the facial nerve in the surgical field can be reliably achieved by direct electrical stimulation; potentially dangerous events can be identified in real time by the free-running EMG and the processed EMG, and almost in real time by facial nerve evoked potentials. Intraoperative prognostics are hampered by false-positive results with all available methods and have limited reliability.