Surgical treatment of cystic pituitary adenomas: literature-based definitions and postoperative outcomes.

BACKGROUND AND OBJECTIVES: To survey the applied definitions of 'cystic' among pituitary adenomas and evaluate whether postoperative outcomes differ relative to non-cystic counterparts. METHODS: A literature search and meta-analysis was performed using PRISMA guidelines. Studies were eligible if novel data were reported regarding the applied definition of 'cystic' and postoperative outcomes among cases of surgically treated pituitary adenomas. Data were pooled with random effects meta-analysis models into cohorts based on the applied definition of 'cystic'. Categorical meta-regressions were used to investigate differences between cohorts. Among studies comparing cystic and non-cystic pituitary adenomas, meta-analysis models were applied to determine the Odds Ratio [95% Confidence Interval]. Statistical analyses were performed using Comprehensive Meta-Analysis (CMA, 4.0), with a priori significance defined as P < 0.05. RESULTS: Ten studies were eligible yielding 283 patients with cystic pituitary adenomas. The definitions of 'cystic' mainly varied between the visual appearance of cystic components on preoperative magnetic resonance imaging and a volumetric definition requiring 50% or greater of tumor volume exhibiting cystic components. Tumor diameter was seldom reported with an associated standard deviation/error, limiting meta-analyses. When the data were pooled in accordance with the definition applied, there were no significant differences in the rates of gross total resection (P = 0.830), endocrinologic remission (P = 0.563), and tumor recurrence (P = 0.320). Meta-analyses on studies comparing cystic versus non-cystic pituitary adenomas indicated no significant difference in the rates of gross total resection (P = 0.729), endocrinologic remission (P = 0.857), and tumor recurrence (P = 0.465). CONCLUSION: Despite some individual studies describing a significant influence of pituitary adenoma texture on postoperative outcomes, meta-analyses revealed no such differences between cystic and non-cystic pituitary adenomas. This discrepancy may be explained in part by the inconsistent definition of 'cystic' and between-group differences in tumor size. A notion of a field-standard definition of 'cystic' among pituitary adenomas should be established to facilitate inter-study comparisons.

Full Endoscopic Transcranial Resection of Meningiomas.

OBJECTIVE: Tumors of the skull base can be accessed through different routes. Recent advantages in minimally invasive techniques have shown that very different routes can be applied for optimal tumor resection depending on the technical equipment, the surgeon's preference, and the individual anatomy of the pathology. Here, the authors present their technique for pure endoscopic transcranial tumor resection in meningiomas. METHODS: Out of the cases of the Department of Neurosurgery, Homburg Saar Germany of the last 10 years, all endoscopic procedures for meningiomas were analyzed. Particular attention was given to evaluating the peculiarities of those meningiomas that were treated purely endoscopically. RESULTS: While the endoscope was used in a large number of skull base meningiomas in endonasal approaches or for endoscopic inspection in transcranial skull base surgery, only a small number of meningiomas was selected for a purely endoscopically performed resection. The characteristics of these cases were rather a small lesion, straight access, and a keyhole position of the craniotomy. A complete resection of the tumor was achieved in all cases. Conversion to the microscope was not necessary in any case. There were no technical issues or complications associated with a fully endoscopic resection. DISCUSSION: The endoscope is a valuable tool for visualization in meningioma surgery. In most cases, it is applied for an endonasal route or for endoscopic inspection in transcranial microsurgical cases. However, small to medium-sized meningiomas that can be accessed through the keyhole approach are good candidates for pure endoscopic resection. Because of the very high magnification and the minimally invasive nature of this approach, it should be considered more frequently in suitable lesions.

Endonasal Route for Tuberculum and Planum Meningiomas.

Tuberculum and planum meningiomas are challenging tumors per their critical location and neurovascular relationships. The standard treatment is usually represented by complete tumor removal, being the transcranial approaches the well-established routes. During the last decades, novel surgical routes have been experimented with emphasis on the concept of minimal invasive approaches. The peculiar perspective from below the endoscopic endonasal approach provides a short and direct access avoiding brain and neurovascular structures manipulation, featuring excellent outcomes and a reduced morbidity. Ideal indications are small or medium size midline meningiomas, with wide tuberculum sellae angle and deep sella at the sphenoid sinus, possibly with no optic nerve and/or vessels encasement. Adequate removal of paranasal structures and extended bony opening over the dural attachment provide a wide surgical corridor ensuring safe intradural exposure at the suprasellar area. The main advantage is related to early decompression of the optic apparatus and reduced manipulation of subchiasmatic perforating vessels, with improved visual outcomes. Direct exposure of the inferomedial aspect of the optic canals allows for maximal decompression in cases of tumor extending within. Transcranial approaches tend to be selected for larger tumors with lateral extension beyond optic nerves and supraclinoid carotid arteries, in inaccessible areas from an endonasal corridor.

Transorbital Route to Intracranial Space.

The endoscopic superior eyelid transorbital approach has emerged as a notable and increasingly utilized surgical technique in recent years. This chapter presents an overview of the approach, tracing its historical development and highlighting its growing acceptance within the skull base community.Beginning with an introduction and historical perspective, the chapter outlines the evolution of the transorbital approach, shedding light on its origins and the factors driving its adoption. Subsequently, a comprehensive exploration of the anatomic bone pillars and intracranial spaces accessible via this approach is provided. Hence, five bone pillars of the transorbital approach were identified, namely the lesser sphenoid wing, the anterior clinoid, the sagittal crest, the middle cranial fossa, and the petrous apex. A detailed correlation of those bone targets with respective intracranial areas has been reported.Furthermore, the chapter delves into the practical application of the technique through a case example, offering insights into its clinical utility, indications, and limitations.

Effect of endoscopic endonasal skull base approaches on olfactory function and facial development in children.

INTRODUCTION: Endoscopic approaches for skull base pathologies are increasingly being performed, and the subsequent complications, especially in the long term, have also been partially clarified. However, there is no information on the effects of endoscopic endonasal skull base surgeries (EESBS) in children on odor and facial development in parallel with long-term development. We conducted this study to investigate postoperative olfactory function and facial development in pediatric patients who underwent skull base surgery using the endoscopic endonasal method. METHODS: We evaluated the smell test, sinonasal symptoms, and facial development of pediatric patients who underwent endoscopic endonasal skull base surgery after long-term follow-up. Odor was evaluated using the "Sniffin' Sticks" test kit, which assessed the T (odor threshold), D (odor discrimination), and I (odor identification) parameters. Sinonasal symptoms were evaluated using the SNOT-22 (sinus-nose outcome test) questionnaire. SNA (sella-nasion-A point), SNB (sella-nasion-B point), and ANB (A point-nasion-B point) angles were calculated from maxillofacial tomography and magnetic resonance imaging) to evaluate facial development. Data were compared with those of the healthy control group. RESULTS: We included 30 patients comprising 19 (63.3%) boys and 11 (36.7%) girls, with no age difference between case and control groups. The mean follow-up period was 7 years. Odor test data, cephalometric measurements, and SNOT-22 analysis results showed no statistically significant differences between the two groups. CONCLUSION: To our knowledge, this is a comprehensive study with the longest follow-up period in terms of evaluation of facial development after EESBS in children to analyze odor using the Sniffin' Sticks test kit and the quality of life using SNOT-22. Olfactory function, facial development, and quality of life remained unaffected after long-term follow-up after EESBS  in children. Although this surgical approach is minimally invasive, we recommend considering the possibility of complications, and the procedure should be performed by an experienced surgical team with adequate equipment.

Letter to the Editor: "Exploring optimal microscopic keyhole access to the skull base: an anatomical evaluation of transciliary supraorbital and transpalpebral orbitofrontal craniotomy approaches".

This letter to the editor examines the recent comparative study by Santos et al. (2024) on transciliary supraorbital (TCA) and transpalpebral (TPA) approaches for skull base access. The original article offers valuable insights into the anatomical distinctions and potential clinical applications of each approach. The letter praises the methodical analysis presented in the study while proposing future directions incorporating advanced imaging technologies and expanded clinical trials to enhance surgical precision and outcomes. Additionally, it suggests integrating longitudinal studies to evaluate patient outcomes, thereby refining the procedural choice based on specific clinical scenarios.

Endonasal endoscopic or endoscopic-assisted transcranial surgery of Rathke's cleft cysts: does the approach and surgical technique influence the radicality and recurrence rate?

OBJECTIVE: Resections of symptomatic Rathke's cleft cysts (RCCs) are mainly performed via an endonasal transsphenoidal approach. However, there is a lack of equivalent data in current literature concerning transcranial keyhole approach in the treatment of RCCs. In order to find general recommendations for the surgical treatment of RCCs also with regard to recurrence, the object of this study is the analysis and comparison of both techniques. METHODS: Twenty-nine patients having been surgically treated between January 2004 and August 2019 were retrospectively analysed. The transsphenoidal approach was chosen in 16 cases and the transcranial keyhole approach in 13 cases. Both surgical techniques were analyzed and compared concerning preoperative symptoms and cyst characteristics, complications, surgical radicality, endocrinological and ophthalmological outcome and recurrences in patients´ follow up. RESULTS: The postoperative outcome of both techniques was identic and showed highly satisfying success rates with 92% for neurological deficits, 82% for endocrinological dysfunctions and 86% for visual deficits. In contrast, momentous postoperative complications were significantly more likely after transsphenoidal operations. After a mean follow-up time of 5.7 years, the recurrence rates of both cohorts were the same with 0% each. CONCLUSIONS: Regarding its equal outcome with its lower complication rate, the authors suggest using the supraorbital keyhole approach for RCCs whose anatomical configuration allow both techniques. Yet, the decision should always consider the surgeon's personal experience and other individual patient characteristics. Further studies with higher numbers of cases and longer follow-up periods are necessary to analyse the effect of the selected approach on recurrence.

Endoscopic transorbital approach bone pillars: a comprehensive stepwise anatomical appraisal.

OBJECTIVE: The endoscopic superior eyelid transorbital approach has garnered significant consideration and gained popularity in recent years. Detailed anatomical knowledge along with clinical experience has allowed refinement of the technique as well as expansion of its indications. Using bone as a consistent reference, the authors identified five main bone pillars that offer access to the different intracranial targeted areas for different pathologies of the skull base, with the aim of enhancing the understanding of the intracranial areas accessible through this corridor. METHODS: The authors present a bone-oriented review of the anatomy of the transorbital approach in which they conducted a 3D analysis using Brainlab software and performed dry skull and subsequent cadaveric dissections. RESULTS: Five bone pillars of the transorbital approach were identified: the lesser sphenoid wing, the sagittal crest (medial aspect of the greater sphenoid wing), the anterior clinoid, the middle cranial fossa, and the petrous apex. The associations of these bone targets with their respective intracranial areas are reported in detail. CONCLUSIONS: Identification of consistent bone references after the skin incision has been made and the working space is determined allows a comprehensive understanding of the anatomy of the approach in order to safely and effectively perform transorbital endoscopic surgery in the skull base.

The trans-sylvian trans-petrosal "half & half" approach-a how I do it.

BACKGROUND: Petroclival meningiomas are one of the most challenging tumors to be operated in the realm of neurosurgery. Many approaches have been developed over the years. METHOD: The authors describe the Half & Half (H&H) approach whose main indication is petroclival meningiomas with suprasellar extension. The part of the tumor located above CN III and in the retrochiasmatic space is addressed through a trans-sylvian, while the petroclival portion is through an extradural anterior petrosectomy approach. The wide surgical corridor given by this approach allows extensive tumor resection while avoiding the risk associated with the manipulation of intracavernous neurovascular structures. CONCLUSION: The H&H approach is an effective strategy to maximize the safe resection of petroclival meningiomas.

Marsupialization as an alternative to reconstruction in endoscopic skull base surgery. How I do it.

BACKGROUND: To treat extradural solid-cystic lesions of the ventral skull base, a pedicled nasoseptal flap (NSF) maintains patency of the marsupialized cavity and prevents restenosis and cyst recurrence. METHODS: The authors provide a step-by-step description of the surgical technique valid in different lesions of the skull base, all treated via the endoscopic endonasal approach (EEA). The application is demonstrated by an operative video. CONCLUSION: In selected lesions, endoscopic marsupialization using an NSF ensures drainage and ventilation of the surgical cavity. Re-epithelialization provided by a pedicled flap is a viable alternative to multilayer skull base reconstruction.

A randomized prospective comparative study on sinonasal morbidity and quality of life of transsphenoidal endoscopic surgery for pituitary adenomas: endonasal versus trans-septal approach.

PURPOSE: Endoscopic endonasal transsphenoidal approach (Endonasal approach) is commonly used to treat pituitary adenomas. The extent of dissection possibly changes the anatomy and the physiology of the nasal cavities and could give rise to post-operative morbidity and the quality of life (QoL). The purpose of this study was to investigate sinonasal morbidity and general QoL in patients who underwent surgery for treatment of pituitary adenoma, comparing Endonasal and endoscopic trans-septal transsphenoidal approach (Trans-septal approach). METHODS: A prospective observational study, recruiting 40 patients undergoing surgery for pituitary adenoma, 20 via Endonasal approach and 20 via Trans-septal approach at our institution. Surveys with Sinonasal Outcome Test-22 (SNOT-22), Chronic Sinusitis Survey (CSS), and Short Form Health Survey 36 version 2 (SF-36v2) were obtained to collect QoL data pre- and postoperatively. RESULTS: All the 40 patients completed the questionnaires. At 6 months postoperatively, the SNOT-22 and CSS score shows significant improvements both in Endonasal approach (p = 0.01) and in Trans-septal approach (p = 0.02). No significant difference in sinonasal morbidity is observed between the two groups for SNOT-22 (p = 0.13) and CSS scores, except for sinus headache (p = 0.49), with a better score in Endonasal approach. The mean SF-36v2 scores remain the same in pre- and post-operative periods, but an improvement in time is seen in general health (p = 0.027), and general health compared to one year ago (p < 0.001). CONCLUSIONS: Endoscopic transsphenoidal surgery has negligible morbidity and does not negatively affect the nasal function in the long term. Endonasal approach and Trans-septal approach are comparable in terms of morbidity outcomes and general QoL, leaving the choice of the approach to the surgeon preference.

Peri-operative management of endoscopic endonasal cerebrospinal fluid leak repair: an international survey.

PURPOSE: Peri-operative management of nasal cerebrospinal fluid (CSF) leaks is not consensual due to limited evidence. The main aim of this study was to identify key factors in peri-operative management of endoscopic endonasal CSF leak repair among international experts. METHODS: A 60-item survey questionnaire collected opinions of members of international learned societies of ENT surgeons and neurosurgeons on nasal packing, post-operative instructions, antibiotic prophylaxis, and CSF volume depletion. RESULTS: The survey had 153 respondents (124 otorhinolaryngologists and 29 neurosurgeons). A resting position was recommended by 85% (130/151) of respondents for extended CSF leak of the anterior skull base, mainly in Fowler's position (72% (110/153)). Nasal packing was used by 85% (130/153) of respondents; 33.3% (51/153) used it to stabilize the reconstruction, and 22.2% (34/153) to prevent bleeding. It was usually removed after 48 h in 44.4% of cases (68/153). CSF depletion was considered by 47.1% (72/153) of respondents in case of CSF leak recurrence and by 34.6% (53/153) in cases of increased intracranial pressure. All respondents gave specific postoperative instructions to patients including driving, running, swimming, diving restrictions and flighting restrictions. In subgroup analysis, ENT surgeons more often recommended a resting position than neurosurgeons (71% vs. 37.9% ; p = 0.0008) and prescribed more antibiotics (82.3% vs. 21.4% ; p < 0.0001). CONCLUSION: Although postoperative management after CSF closure remains challenging and not codified, this international survey revealed some points of consensus concerning resting position and restriction of post-operative activities. Prospective clinical studies must be undertaken to evaluate their efficiency.

Cochlear implantation in patients with inner ear schwannomas: a systematic review and meta-analysis of audiological outcomes.

PURPOSE: In patients with inner ear schwannomas (IES), reports on hearing rehabilitation with cochlear implants (CI) have increased over the past decade, most of which are case reports or small case series. The aim of this study is to systematically review the reported hearing results with CI in patients with IES considering the different audiologic outcome measures used in different countries. METHODS: According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline, a search of published literature was conducted. We included patients with IES (primary or with secondary extension from the internal auditory canal (IAC) to the inner ear, sporadic or NF2 related) undergoing cochlear implantation with or without tumour removal. The audiological results were divided into the categories "monosyllables", "disyllables", "multisyllabic words or numbers", and "sentences". RESULTS: Predefined audiological outcome measures were available from 110 patients and 111 ears in 27 reports. The mean recognition scores for monosyllabic words with CI were 55% (SD: 24), for bisyllabic words 61% (SD: 36), for multisyllabic words and numbers 87% (SD: 25), and 71% (SD: 30) for sentences. Results from for multisyllabic words and numbers in general showed a tendency towards a ceiling effect. Possible risk factors for performance below average were higher complexity tumours (inner ear plus IAC/CPA), NF2, CI without tumour removal ("CI through tumour"), and sequential cochlear implantation after tumour removal (staged surgery). CONCLUSION: Hearing loss in patients with inner ear schwannomas can be successfully rehabilitated with CI with above average speech performance in most cases. Cochlear implantation thus represents a valuable option for hearing rehabilitation also in patients with IES while at the same time maintaining the possibility of MRI follow-up. Further studies should investigate possible risk factors for poor performance. Audiological tests and outcome parameters should be reported in detail and ideally be harmonized to allow better comparison between languages.

Delayed facial nerve palsy after vestibular schwannoma resection: risk factors, extent and prognosis.

INTRODUCTION: Facial nerve palsies may develop during the postoperative period of microsurgical removal of vestibular schwannomas (VSs), even after normal facial function for days or weeks after surgery. The aim of this study was to identify the pathomechanism and predictive factors of delayed palsy. MATERIAL AND METHOD: The clinical data of 193 patients who underwent vestibular schwannoma surgery between 2012 and 2021 were retrospectively analyzed. A total of 134 patients were included. The patients showed intact facial nerve function up to 24 h after surgery. All patients (n = 20) with palsy from postoperative day 4 were included and collectively referred to as delayed facial nerve palsy (DFNP). Various factors were checked using a binomial regression analysis. RESULTS: The mean age of patients with DFNP was 57.8 years (55% female, 45% male). 70% had VS with KOOS ≥ 3, and 60% underwent surgery via a translabyrinthine approach Among the 16 patients with DFNP-related neurotropic pathogens, 25% were seropositive for herpes simplex virus. Most patients (n = 9/20) experienced onset of palsy between postoperative days 6 and 10. Of the four variables included in the significance test, three were significant: KOOS ≥ 3 (p < .04), ipsilateral vestibular organ failure (p < .05), and age group (p < .03). After therapy, 100% of patients recovered almost complete facial nerve function. The parameters mentioned above (KOOS classification and ipsilateral vestibular dysfunction) could be proven risk factors for the occurrence of DFNP.

Paediatric endoscopic endonasal middle skull base reconstruction: retrospective analysis of 78 patients treated in a single tertiary care paediatric center.

INTRODUCTION: Skull base pathologies in the paediatric population are rare and require treatment by multiple qualified specialists. The endoscopic endonasal approach has revolutionized surgical treatment because it is less invasive than existing treatments.The goal of this study was to retrospectively review our experience with the reconstruction of paediatric skull middle base defects and associated complications. MATERIALS AND METHODS: We analysed medical records from patients aged ≤ 18 years who were treated at our centre between 2013 and 2021. Patients treated with an endoscopic skull base approach and reconstruction, and who had complete clinical and radiological documentation and a minimum follow-up of 12 months, were included in the analysis. Personal data, reconstructive techniques, and complications were analysed. RESULTS: A total of 78 patients met the inclusion criteria and were enrolled in the study. Of these patients, 32 were male and 46 were female, and the mean age was 11.5 years. The main signs and symptoms were as follows: bitemporal hemianopsia in 53 cases, visual impairment in 23 cases, and headache in 30 cases. The most frequent aetiologies were craniopharyngioma (38 cases), pituitary adenoma (23 cases), and clivus chordoma (4 cases). All patients were treated via a pure endoscopic approach. For reconstruction, a multilayer technique was used in 18 cases, naso-septal flap in 43 cases, Gasket-Seal technique in 12 cases, and heterologous reconstruction in 5 cases. Only six patients presented a major complication: two had a postoperative cerebral spinal fluid leak, one developed a brain abscess, and three had diabetes insipidus.The mean follow-up period was 23.4 months.There were no statistically significant differences in postoperative CSF leak in relation to different reconstructive techniques. CONCLUSION: Endoscopic endonasal skull base surgery is a safe and effective treatment for paediatric middle skull base pathologies. Reconstruction techniques have a high success rate of 96.5-100%, and the rate of associated complications is < 3%.

Conventional clinical signs and symptoms are poor predictors of postoperative cerebrospinal fluid leak: A single-centre cohort perspective.

BACKGROUND: Postoperative cerebrospinal fluid (CSF) leak remains a concerning complication of the endoscopic endonasal approach (EEA) for skull base pathology. Signs and symptoms suggesting CSF leak often trigger additional workup during the postoperative course. We systematically evaluate associations between subjectively reported clinical signs/symptoms noted during the immediate postoperative period and incidence of postoperative CSF leaks. METHODS: Retrospective chart review was conducted at a tertiary academic medical centre including 137 consecutive patients with intraoperative CSF leak during EEA with primary repair between July 2018 and August 2022. Postoperative CSF leak associations with clinical signs and symptoms were evaluated using positive (PPV) and negative predictive values (NPV), sensitivity, specificity and odds ratio (OR) via univariate logistic regression. RESULTS: Seventy-nine patients (57.7%) had high-flow leaks repaired and 5 (3.6%) developed CSF leaks postoperatively. Of reported symptoms, rhinorrhea was most common (n = 52, 38.0%; PPV [95% CI] = 7.6% [4.8%, 11.9%]), followed by severe headache (n = 47, 34.3%; 6.3% [3.1%, 12.5%]), dizziness (n = 43, 31.4%; 2.3% [0.4%, 12.1%]), salty or metallic taste (n = 20, 14.6%; 9.9% [3.3%, 25.8%]), and throat drainage (n = 10, 7.3%; 9.9% [1.7%, 41.4%]). Nausea or vomiting constituted the most reported sign concerning for CSF leak (n = 73, 53.3%; PPV [95% CI] = 4.1% [2.0%, 8.1%]). On univariate regression, no sign or symptom, including rhinorrhea (OR [95% CI] = 7.00 [0.76-64.44]), throat drainage (3.42 [0.35-33.86]), salty/metallic taste (4.22 [0.66-27.04]), severe headache (3.00 [0.48-18.62]), dizziness (0.54 [0.06-4.94]), fever (3.16 [0.50-19.99]), and nausea/vomiting (1.33 [0.22-8.21]), associated with postoperative CSF leak. CONCLUSIONS: A range of subjectively reported symptoms and signs failed to predict postoperative CSF leak. Further investigation is warranted to inform appropriate attention and response.

Jugular bulb anatomical variations and pneumatization patterns: a comprehensive CBCT analysis.

PURPOSE: This study aims to assess the anatomical possibilities of the jugular bulb (JB). METHODS: Fifty archived CBCT scans were analyzed. RESULTS: The average distance between the internal acoustic canal (IAC) and the JB was 7.97 mm on both sides (Right: SD = 2.56 mm, range 3.16-13.3 mm; Left: SD = 2.5 mm, range 2.9-13.6 mm). JB walls' pneumatization was classified into eight patterns. Deep petrosal cells (DPCs) prevailed in the lateral wall of the JB. The absence of pneumatization (NP) was commonly found on the left side. The presence of infralabyrinthine and hypotympanic cells varied. Less common types included accessory occipital cells (AOCs), posteromedial tracts (PMTs), and basi-occipital cells (BOCs), which determined a consistent variation of the lateral wall pneumatization patterns. Pneumatization of the medial wall was not observed in 50 right sides and 49 left sides. The inferior wall analysis revealed symmetry in AOC distribution and a predominant occurrence of NP. Cases with hypotympanum (HT) in the lateral wall showed a statistically significant IAC-JB distance increase by an average of 4.67 mm compared to NPs. Specific pneumatizations, particularly HT on the lateral side, have a significant effect on the IAC-JB distance, showing a clear pattern of increasing distance from DPC to NP and then to HT. A significant distance increase in HT pneumatization was noted. There were also recorded instances of JB hypoplasia and hyperplasia, JB diverticula, dehiscent JBs, and high JBs. CONCLUSION: This study establishes a novel classification of JB pneumatizations to aid in the understanding of the temporal bone anatomy.

Single-Center Experience in Microsurgical Resection of Acoustic Neurinomas and the Benefit of Microscope-Based Augmented Reality.

Background and Objectives: Microsurgical resection with intraoperative neuromonitoring is the gold standard for acoustic neurinomas (ANs) which are classified as T3 or T4 tumors according to the Hannover Classification. Microscope-based augmented reality (AR) can be beneficial in cerebellopontine angle and lateral skull base surgery, since these are small areas packed with anatomical structures and the use of this technology enables automatic 3D building of a model without the need for a surgeon to mentally perform this task of transferring 2D images seen on the microscope into imaginary 3D images, which then reduces the possibility of error and provides better orientation in the operative field. Materials and Methods: All patients who underwent surgery for resection of ANs in our department were included in this study. Clinical outcomes in terms of postoperative neurological deficits and complications were evaluated, as well as neuroradiological outcomes for tumor remnants and recurrence. Results: A total of 43 consecutive patients (25 female, median age 60.5 ± 16 years) who underwent resection of ANs via retrosigmoid osteoclastic craniotomy with the use of intraoperative neuromonitoring (22 right-sided, 14 giant tumors, 10 cystic, 7 with hydrocephalus) by a single surgeon were included in this study, with a median follow up of 41.2 ± 32.2 months. A total of 18 patients underwent subtotal resection, 1 patient partial resection and 24 patients gross total resection. A total of 27 patients underwent resection in sitting position and the rest in semi-sitting position. Out of 37 patients who had no facial nerve deficit prior to surgery, 19 patients were intact following surgery, 7 patients had House Brackmann (HB) Grade II paresis, 3 patients HB III, 7 patients HB IV and 1 patient HB V. Wound healing deficit with cerebrospinal fluid (CSF) leak occurred in 8 patients (18.6%). Operative time was 317.3 ± 99 min. One patient which had recurrence and one further patient with partial resection underwent radiotherapy following surgery. A total of 16 patients (37.2%) underwent resection using fiducial-based navigation and microscope-based AR, all in sitting position. Segmented objects of interest in AR were the sigmoid and transverse sinus, tumor outline, cranial nerves (CN) VII, VIII and V, petrous vein, cochlea and semicircular canals and brain stem. Operative time and clinical outcome did not differ between the AR and the non-AR group. However, use of AR improved orientation in the operative field for craniotomy planning and microsurgical resection by identification of important neurovascular structures. Conclusions: The single-center experience of resection of ANs showed a high rate of gross total (GTR) and subtotal resection (STR) with low recurrence. Use of AR improves intraoperative orientation and facilitates craniotomy planning and AN resection through early improved identification of important anatomical relations to structures of the inner auditory canal, venous sinuses, petrous vein, brain stem and the course of cranial nerves.

Melanoma of the external auditory canal: case report and systematic literature review.

Melanoma of the external auditory canal (EAC) is particularly rare and poorly understood, with limited available data on management and survival. This systematic review aims to analyze existing data and provide insights into the management and prognosis the beginning of EAC melanoma. It is conducted using Pubmed and Scopus databases from the beginning to July 2023 and it follows the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) 2020 guidelines. Searches are performed using the search string "(melanoma) AND (external auditory canal)".The review includes a total of 30 patients diagnosed with EAC melanoma, supplemented by an additional case from the authors' clinical experience. The role of Breslow thickness as a determining factor for the choice of surgery remains inconclusive due to limited available data. Sentinel lymph node biopsy and adjuvant therapy are sparingly employed, indicating the need for standardized guidelines. Patients in the study demonstrate a 50% overall survival rate at 5 years.EAC Melanoma is a rare and aggressive malignancy with limited therapeutic guidelines. Surgical interventions, including wide local excision and lateral temporal bone resection, are the primary treatment options for patients without distant metastases.

Effects of Endoscopic Sinus Surgery on Olfactory Function.

PURPOSE OF REVIEW: To review the effects of endoscopic sinus surgery and endonasal approaches to the skull base on olfaction. RECENT FINDINGS: Advancements in endonasal endoscopic approaches to the sinuses and skull base allow for direct treatment of a variety of sinonasal and skull base diseases. However, these extended approaches will often require manipulation of normal anatomical structures and the olfactory neuroepithelium. Depending on the planned procedure and extent of disease, the prognosis of olfactory perception can vary significantly among patients. Endoscopic sinonasal surgical procedures may impact olfaction. Optimizing olfactory function requires proper surgical techniques, gentle handling of tissue, and perioperative care. Surgeons must discuss objectives and manage patient expectations. Routine olfactory assessment is crucial in surgical work-up and follow-up. Preserving anatomical structures while addressing the obstruction of the olfactory cleft helps to prevent decreased olfactory threshold. However, smell identification and discrimination do not always correlate with sinonasal anatomy.