Skull Base Surgery Research Articles

The importance of the palatine bone for endoscopic endonasal skull base surgery.

Endoscopic endonasal skull base surgery is increasingly prevalent, with its scope expanding from pathogens in the midline region to those in the paramedian region. Maximizing anterior sphenoidectomy is important for the median approach, and lateralizing the pterygopalatine fossa is crucial for the paramedian approach. Maximizing the surgical corridor in the nasal cavity and minimizing damage to neurovascular structures are vital for establishing a surgical field with minimal bleeding, ensuring safe, precise, and gentle procedures. However, the relationship between the maxillofacial and skull base bones in endoscopic endonasal skull base surgery is difficult to understand because these bones are intricately articulated, making it challenging to visualize each bone's outline. Understanding important bones and their related neurovascular structures is essential for all skull base surgeons to maximize the surgical corridor and minimize iatrogenic injury to neurovascular structures. This study aimed to elucidate the role of the palatine bone from a microsurgical anatomical perspective. Three dry skulls were used to demonstrate the structure of the palatine bone and its relationship with surrounding bones. A formalin-perfused cadaveric head was dissected to show the related neurovascular structures. The arteries and veins of the cadaveric heads were injected with red- and blue-colored silicon. Dissection was performed using a surgical microscope and endoscope. In addition, the utilization of the palatine bone as a landmark to identify neurovascular structures, which aids in creating a wider surgical field with less bleeding, was shown in two representative cases. The palatine bone consists of unique complex structures, including the sphenoidal process, ethmoidal crest, pterygopalatine canal, and sphenopalatine notch, which are closely related to the sphenopalatine artery, maxillary nerve, and its branches. The ethmoidal crest of the palatine bone is a well-known structure that is useful for identifying the sphenopalatine foramen, controlling the sphenopalatine artery and nerve, and safely opening the pterygopalatine fossa. The sphenoidal process of the palatine bone is a valuable landmark for identifying the palatovaginal artery, which is a landmark used to safely and efficiently expose the vidian canal. The sphenoidal process is easily cracked with an osteotome and removed to expose the palatovaginal artery, which runs along the pharyngeal groove, just medial to the vidian canal. By opening the pterygopalatine canal (also known as the greater palatine canal), further lateralization of the periosteum-covered pterygopalatine fossa contents can be achieved. Overall, the sphenoidal process and ethmoidal crest can be used as important landmarks to maximize the surgical corridor and minimize unnecessary injury to neurovascular structures.

Microanatomy of the human tunnel of Corti structures and cochlear partition-tonotopic variations and transcellular signaling.

Auditory sensitivity and frequency resolution depend on the optimal transfer of sound-induced vibrations from the basilar membrane (BM) to the inner hair cells (IHCs), the principal auditory receptors. There remains a paucity of information on how this is accomplished along the frequency range in the human cochlea. Most of the current knowledge is derived either from animal experiments or human tissue processed after death, offering limited structural preservation and optical resolution. In our study, we analyzed the cytoarchitecture of the human cochlear partition at different frequency locations using high-resolution microscopy of uniquely preserved normal human tissue. The results may have clinical implications and increase our understanding of how frequency-dependent acoustic vibrations are carried to human IHCs. A 1-micron-thick plastic-embedded section (mid-modiolar) from a normal human cochlea uniquely preserved at lateral skull base surgery was analyzed using light and transmission electron microscopy (LM, TEM). Frequency locations were estimated using synchrotron radiation phase-contrast imaging (SR-PCI). Archival human tissue prepared for scanning electron microscopy (SEM) and super-resolution structured illumination microscopy (SR-SIM) were also used and compared in this study. Microscopy demonstrated great variations in the dimension and architecture of the human cochlear partition along the frequency range. Pillar cell geometry was closely regulated and depended on the reticular lamina slope and tympanic lip angle. A type II collagen-expressing lamina extended medially from the tympanic lip under the inner sulcus, here named "accessory basilar membrane." It was linked to the tympanic lip and inner pillar foot, and it may contribute to the overall compliance of the cochlear partition. Based on the findings, we speculate on the remarkable microanatomic inflections and geometric relationships which relay different sound-induced vibrations to the IHCs, including their relevance for the evolution of human speech reception and electric stimulation with auditory implants. The inner pillar transcellular microtubule/actin system's role of directly converting vibration energy to the IHC cuticular plate and ciliary bundle is highlighted.

Sinonasal inverted papilloma and predictors of health-related quality of life after endonasal endoscopic surgery: A prospective cohort study.

Existing knowledge on health-related quality of life (HRQoL) after surgical removal of sinonasal inverted papilloma (IP) is limited. Moreover, predictors for a better or worse post-operative HRQoL outcome are not known. Our aim was to assess HRQoL in all three health domains (physical, psychological, and social), track its post-operative trajectory, investigate if pre-operative observations could predict distinct post-operative HRQoL outcomes, and evaluate whether physicians' interventions could contribute to improved post-operative HRQoL. Prospective cohort study. Tertiary referral hospital. Seventy-four patients who underwent surgery for an IP were included. They were asked to fill in the Endonasal Endoscopic Sinus and Skull-Base Surgery Questionnaire (EES-Q) pre-operatively, and then 2 weeks, 3 months, and 1 year post-operatively. Linear mixed models analyses were performed to evaluate the overall post-operative HRQoL and the separate health domains, as well as the impact of specific variables (sex, age, American Society of Anaesthesiologists [ASA] classification, smoker, Krouse staging, pre-operative EES-Q score, type of surgery, and post-operative antibiotics) on HRQoL improvement. The total EES-Q score (p < .001) as well as the physical (p < .001), psychological (p = .049), and the social (p = .002) domains significantly improved post-operatively. ASA classification (p = .049), pre-operative EES-Q score (p < .001) and post-operative antibiotics (p = .036) were significant variables. Overall HRQoL, as well as each of the three health domains, improved significantly. A higher ASA score, a higher pre-operative EES-Q score, and the administration of post-operative antibiotics were significant predictors for better HRQoL recovery post-operatively. Further research is necessary to confirm these results.

Venous thromboembolism chemical prophylaxis after skull base surgery

PurposeThere is no guidance surrounding postoperative venous thromboembolism (VTE) prophylaxis using pharmacological agents (chemoprophylaxis) in patients undergoing skull base surgery. The aim of this study was to compare VTE and intracranial haematoma rates after skull base surgery in patients treated with/without chemoprophylaxis.MethodsReview of prospective quaternary centre database including adults undergoing first-time skull base surgery (2009–2020). VTE was defined as deep vein thrombosis (DVT) and pulmonary embolism (PE) within 6 months of surgery. Multivariate logistic regression was used to determine factors predictive of postoperative intracranial haematoma/VTE. Propensity score matching (PSM) was used in group comparisons.ResultsOne thousand five hundred fifty-one patients were included with a median age of 52 years (range 16–89 years) and female predominance (62%). Postoperative chemoprophylaxis was used in 81% of patients at a median of 1 day postoperatively. There were 12 VTE events (1.2%), and the use of chemoprophylaxis did not negate the risk of VTE entirely (p > 0.99) and was highest on/after postoperative day 6 (9/12 VTE events). There were 18 intracranial haematomas (0.8%), and after PSM, chemoprophylaxis did not significantly increase the risk of an intracranial haematoma (p > 0.99). Patients administered chemoprophylaxis from postoperative days 1 and 2 had similar rates of intracranial haematomas (p = 0.60) and VTE (p = 0.60), affirmed in PSM.ConclusionPostoperative chemoprophylaxis represents a relatively safe strategy in patients undergoing skull base surgery. We advocate a personalised approach to chemoprophylaxis and recommend it on postoperative days 1 or 2 when indicated.

The lateral retrocanthal transorbital endoscopic approach to the middle fossa: cadaveric stepwise approach and review of quantitative cadaveric data.

The lateral retrocanthal transorbital endoscopic approach (LRCTEA) facilitates trajectory to the middle fossa, preserving the lateral canthal tendon and thus avoiding postoperative complications such as eyelid malposition. Here, the authors sought to define the surgical anatomy and technique of LRCTEA using a stepwise approach in cadaveric heads and offer an in-depth examination of existing quantitative data from cadaveric studies. The authors performed LRCTEA to the middle cranial fossa under neuronavigation in 7 cadaveric head specimens that underwent high-resolution (1-mm) CT scans preceding the dissections. The LRCTEA provided access to middle fossa regions including the cavernous sinus, Meckel's cave, and medial temporal lobe. The trajectories and endpoints of the approach were confirmed using electromagnetic neuronavigation. A stepwise approach was delineated and recorded. The authors' cadaveric study delineates the surgical anatomy and technique of the LRCTEA, providing a stepwise approach for its implementation. As these approaches continue to evolve, their development and refinement will play an important role in expanding the surgical options available to neurosurgeons, ultimately improving outcomes for patients with complex skull base pathologies. The LRCTEA presents a promising advancement in skull base surgery, particularly for accessing challenging middle fossa regions. However, surgeons must remain vigilant to potential complications, including transient diplopia, orbital hematoma, or damage to the optic apparatus.

A quantitative comparative surgical analysis of the endoscopic transorbital approach and frontotemporal-orbitozygomatic approach for extradural exposure of the cavernous sinus.

Recently, the endoscopic superior eyelid transorbital approach (SETA) has emerged as a potential alternative to access the cavernous sinus (CS). Several previous studies have attempted to quantitatively compare the traditional open anterolateral skull base approaches with transorbital exposure; however, these comparisons have been limited to the area of exposure provided by the bone opening and trajectory, and fail to account for the main avenues of exposure provided by subsequent requisite surgical maneuvers. The authors quantitatively compare the surgical access provided by the frontotemporal-orbitozygomatic (FTOZ) approach and the SETA following applicable periclinoid surgical maneuvers, evaluate the surgical exposure of key structures in each, and discuss optimal approach selection. SETA and FTOZ approaches were performed with subsequent applicable surgical maneuvers on 8 cadaveric heads. The lengths of exposure of cranial nerves (CNs) II-VI and the cavernous internal carotid artery; the areas of the space accessed within the supratrochlear, infratrochlear, and supramaxillary (anteromedial) triangles; the total area of exposure; and the angles of attack were measured and compared. Exposure of the extradural CS was comparable between approaches, whereas access was significantly greater in the FTOZ approach compared with the SETA. The lengths of extradural exposure of CN III, V1, V2, and V3 were comparable between approaches. The FTOZ approach provided marginally increased exposure of CNs IV (20.9 ± 2.36 mm vs 13.4 ± 3.97 mm, p = 0.023) and VI (14.1 ± 2.44 mm vs 9.22 ± 3.45 mm, p = 0.066). The FTOZ also provided significantly larger vertical (44.5° ± 6.15° vs 18.4° ± 1.65°, p = 0.002) and horizontal (41.5° ± 5.40° vs 15.3° ± 5.06°, p < 0.001) angles of attack, and thus significantly greater surgical freedom, and provided significantly greater access to the supratrochlear (p = 0.021) and infratrochlear (p = 0.007) triangles, and significantly greater exposure of the cavernous internal carotid artery (17.2 ± 1.70 mm vs 8.05 ± 2.37 mm, p = 0.001). Total area of exposure was also significantly larger in the FTOZ, which provided wide access to the lateral wall of the CS as well as the possibility for intradural access. This is the first study to quantitatively identify the relative advantages of the FTOZ and transorbital approaches at the target region following requisite surgical maneuvers. Understanding these data will aid in selecting an optimal approach and maneuver set based on target lesion size and location.

Endoscopic transorbital approach in children: surgical technique and early results.

In this study, the authors aimed to describe the endoscopic transorbital approach (ETOA) in children. Six pediatric patients (2 girls and 4 boys) underwent the ETOA for paramedian skull base lesions at a single institution between September 2016 and February 2023. The median age at the time of surgery was 7.5 (range 4-18) years. The median follow-up period was 33 (range 9-60) months. In this series, the ETOA level of difficulty included stage 1 (n = 2, 33.3%), stage 3 (n = 3, 50%), and stage 5 (n = 1, 16.7%). The ETOA was performed for tumor resection in 4 cases; the final pathology consisted of fibrous dysplasia, pilocytic astrocytoma, metastatic neuroblastoma, and choroid plexus papilloma. The procedure was also performed for repair of a petrous apex meningocele and for lateral orbital wall decompression of traumatic lateral rectus muscle entrapment. One patient experienced a transient cranial nerve III palsy after the procedure. There were no operative deaths in this series. In select cases, the ETOA can be considered a minimally invasive alternative for conventional skull base approaches in the armamentarium of pediatric skull base surgery. Further investigation and the accumulation of experience are warranted in the future to enhance the efficacy and applicability of the ETOA in pediatric patients.

Diabetes Insipidus after Endoscopic Endonasal Pituitary Macroadenoma Resection: Correlation of Patient and Surgery-Related Risk Factors.

Purpose This article aims to identify patient- and surgery-related factors that could predict the development of postoperative central diabetes insipidus (DI). Methods This is a retrospective case-control study conducted at a single-institution tertiary referral center. Patients undergoing endoscopic endonasal skull base surgery for pituitary adenoma between November 2018 and April 2023 were recruited. The main outcome measures collected include age, gender, comorbidities, tumor type, postoperative DI, intraoperative and postoperative cerebrospinal fluid (CSF) leak, flow of CSF leak, number of layers required for repair, the use of nasal packing, and hospital length of stay. Results A total of 20 patients developed DI postoperatively. Patients' demographic and comorbidity profile did not correlate with DI development. The encounter of an intraoperative CSF leak was correlated with postop DI (chi-square (1) = 18.35, p < 0.001) with a relative risk (RR) of 2.7 (confidence interval [CI] = 1.37-5.28). The use of nasal packs was also correlated with postop DI (chi-square (1) = 10.17, p = 0.001) with a RR of 1.8 (CI = 1.15-2.87). Defects requiring a two or more layers for reconstruction also correlated with postop DI compared to single layer repairs (chi-square (1) = 12.15, p < 0.001) irrelevant of the materials used. Development of DI postop correlated with an increased hospital length of stay ( t (64) = -3.35, p = 0.001). Conclusion The physician should be careful when evaluating patients with pituitary adenomas in the postoperative period, particularly those with intraoperative CSF leak, nasal packing, and those who underwent multilayer reconstruction of the surgical defect.

American Rhinologic Society expert practice statement part 1: Skull base reconstruction following endoscopic skull base surgery.

The goal of this American Rhinologic Society expert practice statement (EPS) is to summarize the best available evidence for technical factors that optimize outcomes in skull base reconstruction following endoscopic skull base surgery for intradural pathologies. These topics include the use of free mucosal grafts versus vascularized pedicled nasoseptal flaps; the use of autologous versus synthetic grafts; and the roles of lumbar drains, dural sealants, and nasal packing. This EPS was developed following the recommended methodology and approval process as previously outlined. As there are a myriad of techniques and limited agreement on the accepted principles of skull base reconstruction, this EPS aims to summarize the existing evidence and provide clinically meaningful guidance on these divergent practices. Following a modified Delphi approach, five statements were developed, four of which reached consensus and one of which reached near consensus. These statements and the accompanying evidence are summarized along with an assessment of future needs.

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%.

Special Considerations in Pediatric Endoscopic Skull Base Surgery.

Originally pioneered in adults, endoscopic endonasal approaches for skull base pathology are being increasingly applied as a minimally invasive alternative for young children. Intrinsic anatomic differences between these patient populations have sparked discussions on the feasibility, safety, and efficacy of these techniques in pediatric patients. This work aims to serve as a primer for clinicians engaged in the rapidly evolving field of pediatric endoscopic skull base surgery. A succinct overview of relevant embryology, sinonasal anatomy, and diagnostic workup is presented to emphasize key differences and unique technical considerations. Additional discussions regarding select skull base lesions, reconstructive paradigms, potential surgical complications, and postoperative care are also highlighted in the setting of multidisciplinary teams.

Short‐term urinary catheter usage in endoscopic skull base surgery and impact on urinary tract infection and reconstructive outcomes

AbstractObjectivesHospital‐acquired catheter‐associated urinary tract infections (UTIs) have been regarded as preventable adverse events, yet their risk in endoscopic skull base surgery (ESBS) has not been well described despite common use. We determine the incidence of UTI following ESBS and identify contributing clinical factors.MethodsRetrospective review was conducted for a cohort of 229 consecutive adult patients who underwent endoscopic endonasal surgery for treatment of any skull base pathology between July 2018 and June 2022 at a tertiary academic skull base surgery program. Postoperative UTI comprised the primary outcome. Independent variables included patient demographics, use and length of urinary catheterization, and pre‐existing genitourinary conditions.ResultsNosocomial UTIs were identified in 1.3% (3/229) of patients, occurring on postoperative days 2, 9, and 14, respectively; all were catheter‐associated. Overall, 86.0% (197/229) of patients received urinary catheters (mean duration 2.2 ± 1.8 days). Compared to those without, patients with UTI were older (70.0 ± 15.4 vs. 52.2 ± 16.8 years, p = 0.034), had lengthier stays (94.7 ± 126.8 vs. 5.9 ± 8.4 days, p &lt; 0.001), and had prolonged catheterizations (9.3 ± 5.5 vs. 2.1 ± 1.5 days, p &lt; 0.001). Preoperative genitourinary conditions were also associated with UTI development, namely, chronic urinary retention/obstruction (66.7% vs. 4.0%, p = 0.006), urinary incontinence (66.7% vs. 6.2%, p = 0.013), prostate disease (100.0% vs. 17.8%, p = 0.035), and renal dysfunction (100.0% vs. 9.7%, p = 0.001). Among intraoperative cerebrospinal fluid leak patients, postoperative CSF leak incidence was not associated with catheter use versus nonuse (3.3% vs. 12.5%, p = 0.276).ConclusionAlthough UTIs are uncommon in ESBS patients, advanced age, length of stay, duration of indwelling urinary catheterization, and comorbid genitourinary conditions may elevate risk.

Reconstruction of the Large Frontal Sinus Defect With the Small Supporting Bone Pieces in Neurosurgical Anterior Skull Base Surgery

BackgroundLarge defects of frontal sinus (FS) might be difficult to manage effectively. Mismanagement of the large defects could lead to serious postoperative complications in anterior skull base surgery. This study introduces a simple and reliable method applying small supporting bone pieces to cover or insert into large FS defects, then the large defect of FS was transformed into the some small defects which can be sealed by bone wax successfully. MethodsEleven patients underwent anterior skull base surgery for lesions or aneurysms, with the reconstruction of large FS defects by small supporting bone pieces. During craniotomy, mild violations of the FS mucosa were spared and sterilized, while severe violations required mucosal removal. Small supporting bone pieces were obtained from the inner plate of the bone flap, and carefully covered or inserted into the large defects. The large defects were transformed into some small ones, which could be sealed effectively by bone wax. Demographic, intraoperative, and postoperative complication data were collected. ResultsFour patients had severe mucosal violations requiring removal, while seven had mild violations sparing the mucosa. All underwent effective reconstruction with small supporting bone pieces. Median follow-up was 6 months. All cases showed effective FS morphology reconstruction, with no FS-related complications. ConclusionApplying the small supporting bone pieces for large FS defect reconstruction can restore the FS morphology, preserve physiological function, and avoid postoperative complications.

The Complete Anatomy of the Anterior Ethmoidal Artery: A Meta-Analysis with Implications for Sinus and Skull Base Surgery.

Background: The anatomical characteristics of the anterior ethmoidal artery (AEA) exhibit a high degree of variability, especially regarding its topography. Methods: PubMed, Scopus, Embase, Web of Science, Cochrane Library, and Google Scholar were searched to identify all studies that included information regarding the morphometric and topographical characteristics of the AEA. Results: Ultimately, a compilation of 38 studies meeting the predetermined criteria, and possessing comprehensive and pertinent data, were incorporated into the current meta-analysis. In the overall analysis, reports of the AEA being embedded within the skull base or at the level of the skull base producing a bony protrusion were found in 56.91% of cases (95% CI: 43.55-69.80%). The mean diameters of the AEA in the intraorbital and intracranial areas were 0.94 mm and 0.76 mm, respectively. Moreover, the artery coursed most commonly between the second and third lamellae, with a prevalence of 65.82% (95% CI: 55.39-75.56%). Conclusions: The AEA may be at a high risk of iatrogenic injury during various sinus and skull base surgeries, especially if the surgeon performing these procedures is unfamiliar with the vast number of variations this vessel may exhibit. The spatial relationship between this vessel and the skull base is especially variable, and understanding this variability goes hand in hand with intraoperative safety.

Vascular Complications of Endoscopic Transsphenoidal Approach to Sellar Base Lesions

Objective: Vascular complications are one of the most dangerous complications of endoscopic skull base surgeries. The aim of this study was to evaluate vascular complications of endoscopic transsphenoidal surgery in patients with sellar and parasellar lesions.&#x0D; &#x0D; Methods: Between August 1997 and July 2023, a total of 5300 patients underwent endoscopic transsphenoidal surgery for skull base lesions at Kocaeli University Faculty of Medicine, Department of Neurosurgery and Pituitary Research Center. Patients with vascular complications during and after surgery were included into the study.&#x0D; &#x0D; Results: We encountered 12 major vascular injuries, 116 epistaxis, and 50 operation site hematoma in our series.&#x0D; &#x0D; Conclusion: Major vascular injuries are the most life-threatening complicastions. They can cause high mortality. The ways to prevent these injuries seems to have high experience and to investigate preoperative vascular evaluation in detail.

Management of Posttraumatic Cerebrospinal Fluid Leak with Secondary Diffuse Pneumocephalus Complicated by Meningitis and Communicating Hydrocephalus – Illustrative Case Report

Rhinorrhea is a possible complication after different types of traumatic brain injury or neurosurgical procedures, such as skull base operations. Pneumocephalus is a rarely noted complication after severe traumatic brain injury, and it may be accompanied by meningitis and ventriculitis, especially when treatment has been delayed. Treatment of these entities includes conservative and surgical approaches. Pneumocephalus may result in neurologic disturbances threatening a life. Therefore, active patient management with a multidisciplinary team is required to prevent poor outcomes. In the literature, limited cases of rhinorrhea and pneumocephalus are available, including in our country. Pneumocephalus may also occur spontaneously. In 2015, Pishbin et al. identified 10 cases of spontaneous pneumocephalus. The precise incidence of diffuse pneumocephalus after traumatic brain injury is unknown, reported as &lt;1% of cases with rare complications. In this case, a 41-year-old male patient presented at a tertiary university hospital with the chief complaint of headache. A month prior to admission, the patient was discharged from another hospital with multiple skull and facial fractures, pneumocephalus, and traumatic subarachnoid hemorrhage in the left frontal lobe due to fights (Le Fort III). During the second hospitalization, the patient’s clinical status deteriorated. A repeated brain CT demonstrated diffuse pneumocephalus. Rhinorrhea was still present. The external lumbal drainage procedure was performed without stopping the cerebrospinal fluid leak. In children, pediatric inferior turbinate hypertrophy is a frequent cause of nasal breathing difficulties. In this case, no such hypertrophy was observed. It should be considered a nasal obstructive disease not necessarily related to adult entities, frequently associated with other nasal or craniofacial disorders. Early diagnosis and endoscopic management of rhinorrhea, nasal obstruction, and associated complications is vital, as delays can lead to life-threatening issues like hydrocephalus/meningitis. Eventually, the patient developed meningitis and acute communicating hydrocephalus. Right ventriculostomy with a programmable ventriculoperitoneal shunt placement was done (pressure 110 cm H&lt;sub&gt;2&lt;/sub&gt;O), stopping the rhinorrhea. This is an extremely rare case where a patient, after cerebrospinal fluid (CSF) leakage, develops severe complications, including pneumocephalus, meningitis, ventriculitis, and acute communicating hydrocephalus. In the literature, we did not come across case reports presenting all the complications as in this case. This case report will raise knowledge and awareness of such entities, adding to the rare, similar cases reported so far.

Tissue Sealant Impact on Skull Base Reconstruction Outcomes: A Systematic Review and Meta-Analysis.

Despite significant advances in understanding of skull base reconstruction principles, the role of tissue sealants in modifying postoperative cerebrospinal fluid (CSF) leak outcomes remains controversial. We evaluate postoperative CSF leak incidence associated with tissue sealant use in skull base defect repair during endoscopic skull base surgery (ESBS). Web of Science, PubMed/MEDLINE, Scopus, and Cochrane Library. Systematic review and meta-analysis of risk differences (RD). A search strategy identified original studies reporting CSF leakage following ESBS with disaggregation by tissue sealant use and/or type. 27 non-randomized studies (n = 2,403) were included for qualitative and meta-analysis. Reconstruction with a tissue sealant did not significantly reduce postoperative CSF leak risk compared with reconstruction without sealant (RD[95% CI] = 0.02[-0.01, 0.05]). Sub-analyses of dural sealant (-0.02[-0.11, 0.07]) and fibrin glue (0.00[-0.07, 0.07]) compared with no sealant were similarly unremarkable. Postoperative CSF leakage was not significantly modulated in further sub-analyses of DuraSeal (0.02[-0.02, 0.05]), Adherus (-0.03[-0.08, 0.03]), or Bioglue (-0.06[-0.23, 0.12]) versus no dural sealant use, or Tisseel/Tissucol versus fibrin glue nonuse (0.00[-0.05, 0.05]). No significant association was seen comparing dural sealant use versus fibrin glue use on pairwise (0.01[-0.03, 0.05]) or network meta-analysis (-0.01[-0.05, 0.04]). Limitations in source literature prevented sub-analyses stratified by leak characteristics, defect size and location, and accompanying reconstruction materials. Tissue sealant use did not appear to impact postoperative CSF leak incidence when compared with nonuse. Higher quality studies are warranted to thoroughly elucidate the clinical value of adjunct sealant use in endoscopic skull base reconstruction. N/A Laryngoscope, 134:3425-3436, 2024.

The Effects of Nasal Septal Deviation on Anterior Skull Base Parameters.

Introduction Functional endoscopic sinus surgery and endoscopic skull base surgery are frequently performed surgeries today. Nasal septal deviation is a common finding and can affect the surgical area. Therefore, it is important to examine the effect of this deviation on other anatomical structures. Objectıve The aim of the present study was to determine whether there is a relationship between the degree of nasal septal deviation and anterior skull base structures using computed tomography (CT). Methods A total of 312 patients (aged 18 to 65 years old) whose paranasal sinus CT images were available were included in the study. Measurements were obtained on images retrieved from Picture Archiving and Communication System (PACS) and Horos image archive systems in the bone window in the coronal and axial plane. Results The mean age of 312 patients was 33.00 years old (standard deviation [SD] 11.22 years). The presence of septal deviation was not associated with changes in olfactory fossa (OF) depths, Keros degrees, and the angle between the lateral lamella and the cribriform lamella. However, OF depths and Keros degrees on the deviated side of the septum were found to change at a significant level ( p < 0.05). No significant association was observed between the degree of septal deviation and cribriform lamella-lateral lamella angle. Conclusion The study showed significantly increased OF depth and Keros degree on the deviated side of the nasal septum. Performing CT scans before endoscopic sinus surgery and endoscopic skull base surgery is important to increase the chances of a successful surgical outcome and to reduce complications.

Surgical Navigation in the Anterior Skull Base Using 3-Dimensional Endoscopy and Surface Reconstruction

Image guidance is an important adjunct for endoscopic sinus and skull base surgery. However, current systems require bulky external tracking equipment, and their use can interrupt efficient surgical workflow. To evaluate a trackerless surgical navigation system using 3-dimensional (3D) endoscopy and simultaneous localization and mapping (SLAM) algorithms in the anterior skull base. This interventional deceased donor cohort study and retrospective clinical case study was conducted at a tertiary academic medical center with human deceased donor specimens and a patient with anterior skull base pathology. Participants underwent endoscopic endonasal transsphenoidal dissection and surface model reconstruction from stereoscopic video with registration to volumetric models segmented from computed tomography (CT) and magnetic resonance imaging. To assess the fidelity of surface model reconstruction and accuracy of surgical navigation and surface-CT model coregistration, 3 metrics were calculated: reconstruction error, registration error, and localization error. In deceased donor models (n = 9), high-fidelity surface models of the posterior wall of the sphenoid sinus were reconstructed from stereoscopic video and coregistered to corresponding volumetric CT models. The mean (SD; range) reconstruction, registration, and localization errors were 0.60 (0.24; 0.36-0.93), 1.11 (0.49; 0.71-1.56) and 1.01 (0.17; 0.78-1.25) mm, respectively. In a clinical case study of a patient who underwent a 3D endoscopic endonasal transsphenoidal resection of a tubercular meningioma, a high-fidelity surface model of the posterior wall of the sphenoid was reconstructed from intraoperative stereoscopic video and coregistered to a volumetric preoperative fused CT magnetic resonance imaging model with a root-mean-square error of 1.38 mm. The results of this study suggest that SLAM algorithm-based endoscopic endonasal surgery navigation is a novel, accurate, and trackerless approach to surgical navigation that uses 3D endoscopy and SLAM-based algorithms in lieu of conventional optical or electromagnetic tracking. While multiple challenges remain before clinical readiness, a SLAM algorithm-based endoscopic endonasal surgery navigation system has the potential to improve surgical efficiency, economy of motion, and safety.

Usefulness of Preoperative Simulation: Skull Base Approach

Preoperative simulation images creates an accurate visualization of a surgical field. The anatomical relationship of the cranial nerves, arteries, brainstem, and related bony protrusions is important in skull base surgery. However, an operator's intention is unclear for a less experienced neurosurgeon. Three-dimensional(3D)fusion images of computed tomography and magnetic resonance imaging created using a workstation aids precise surgical planning and safety management. Since the simulation images allows to perform virtual surgery, a déjà vu effect for the surgeon can be obtained. Additionally, since 3D surgical images can be used for preoperative consideration and postoperative verification, discussion among the team members is effective from the perspective of surgical education for residents and medical students. Significance of preoperative simulation images will increase eventually.