Introduction  Pedicled nasoseptal flap (NSF) placement is a critical component of skull base reconstruction after endoscopic endonasal approaches (EEAs). The effectiveness of NSF reuse has not been thoroughly studied. Prior reports using flaps harvested at one center and reused at another may have technical variability bias. Methods  We identified patients who underwent both their initial and NSF-reused surgeries at Weill Cornell Medical College from 2004 to 2022 using a prospective database of all EEAs. Surgical pathology, intraoperative leak grade, use of cerebrospinal fluid (CSF) diversion and skull base coverage were examined. The primary outcome measure was occurrence of CSF leak. Results  Fourteen patients (six women, eight men) underwent 14 first time and 14 revision operations with median age of 36.6 years (interquartile range [IQR]: 23.9-61.3) at the time of the NSF reuse. The median interval between the first NSF use and reuse was 70.6 months (IQR: 16.6-87). Eight patients were operated on for pituitary adenoma. Nonadenomas included three craniopharyngiomas and one case each of epidermoid, ependymoma, and chordoma. There were 16 high-flow, 8 low-flow intraoperative leaks, and 4 with no leak. CSF diversion was used in 24 operations. There were three postoperative leaks, one after a first operation and two after NSF reuse. All postoperative CSF leaks, whether first or second operations, occurred in cases with both high-flow intraoperative CSF leak and incomplete NSF coverage ( p  = 0.006). Conclusion  NSF reuse is effective at preventing postoperative CSF leak. The primary predictors of leak are high-flow intraoperative leak and inadequate defect coverage with NSF, regardless of the operation number.

Sphenoid meningoencephaloceles are rare, and their treatment is challenging. In this report, we describe two clinical cases of sphenoid meningoencephalocele, in which one patient presented with a cerebrospinal fluid leak after repeated head trauma, while in the other, sphenoid meningoencephalocele was detected during the study of memory impairment as the patient was otherwise asymptomatic. The CT scans showed bony dehiscence on the lateral wall of the sphenoid sinus filled with soft tissue that was confirmed by MRI as being herniated brain tissue. A transpterygoid endoscopic endonasal approach was performed with a multilayer reconstruction of the defect with success in both cases without perioperative complications. Imaging techniques are fundamental for diagnosis and surgical planning. Treatment using an endoscopic endonasal approach is efficient with very low morbidity.

Aspiration pneumonitis is an inflammatory lung disease caused by the inhalation of oropharyngeal secretions colonized by pathogenic bacteria. Accurate diagnosis of aspiration pneumonitis can be challenging, and cerebrospinal fluid (CSF) rhinorrhea is often overlooked as a rare cause of aspiration. In this case report, we present the case of a 48-year-old male patient who experienced right-sided nasal flow of clear watery secretions for 6 months, accompanied by a dry cough as the major symptom. Through comprehensive assessment of clinical symptoms, sinus imaging, nasal endoscopy, and relevant laboratory testing, a presumptive diagnosis of traumatic cribriform plate fracture with CSF rhinorrhea was made. Chest imaging revealed flocculent ground glass shadows in the bilateral lungs. After ruling out viral pneumonia, nasal endoscopic repair of the skull base defect was performed. The patient\'s dry cough and rhinorrhea symptoms resolved within 1 week after surgery, and the pneumonia showed significant improvement and complete resolution within 2 weeks postoperatively. Despite the absence of characteristic symptoms and evident inhalation factors, chronic CSF rhinorrhea caused by the cribriform plate fracture was ultimately identified as the primary etiology of the patient\'s aspiration pneumonitis. This rare case highlights the importance of considering traumatic CSF rhinorrhea as an uncommon cause of aspiration, which can enhance physicians\' awareness and focus on the less-common etiologies of aspiration. Such awareness can contribute to more accurate diagnosis and early operative intervention, particularly in the context of the coronavirus disease 2019 pandemic.

BACKGROUND: Various graft materials that are classified as autografts, xenografts, and allografts based on their origin have been used to endoscopically repair skull base defects. Tutoplast® (Tutogen Medical GmbH), an allogeneic natural collagen matrix, is processed through chemical sterilization that preserves tissue biocompatibility and structural integrity.
OBJECTIVE: To study the safety and efficacy of Tutoplast Fascia Lata and Tutoplast Temporalis Fascia® as primary graft materials in the endoscopic reconstruction of skull base defects of different sizes and etiologies and to compare the outcomes with those of other traditional graft materials based on our experience.
METHODS: This is a multi-center retrospective chart review of patients who underwent cerebrospinal fluid leak (CSF) endoscopic reconstruction with Tutoplast Fascia Lata or Tutoplast Temporalis Fascia as either a stand-alone reconstruction material or a part of a multilayer reconstruction depending on the defect at Prince Sultan Military Medical City and King Faisal Specialist Hospital and Research Center in Riyadh, Saudi Arabia, between 2017 and 2020. Our inclusion criteria were CSF leak repair with Tutoplast and a transnasal endoscopic approach. We reviewed demographic data, intraoperative and postoperative complications, repair materials, repair failure, defect size and location.
RESULTS: Tutoplast® was used as the primary graft material in 33 cases. Our main outcome was repair success with lack of post operative CSF leak, observed in 30 cases (90.9%). There was no significant association between postoperative CSF leaks and factors including different defect sizes, defect sites, demographic data, hospitalization duration, or postoperative radiation in oncological cases.
CONCLUSIONS: Tutoplast alone or in combination with other materials can be used safely and effectively for skull base defects repair.

Encephaloceles are herniations of intracranial neural tissue and meninges through defects in the skull. Basal encephaloceles are rare anterior skull base defects incident in 1 in 35,000 live births. Sphenoethmoidal encephaloceles are even more uncommon, with an incidence of 1 in 700,000 live births. Anterior skull base encephaloceles may be life-threatening in infants, presenting as airway obstruction and respiratory compromise. They can also present with cerebrospinal fluid (CSF) rhinorrhea, purulent nasal drainage, or meningitis.
To report a novel technique for repairing a giant sphenoethmoidal encephalocele containing eloquent neural tissue.
A 16-mo-old girl presented with progressive airway obstruction from a giant sphenoethmoidal encephalocele that filled her oral cavity. She had multiple congenital anomalies including agenesis of the corpus callosum and cleft lip and palate. Computed tomography showed complete absence of the bony anterior cranial base, and magnetic resonance imaging demonstrated the presence of the pituitary gland and hypothalamus in the hernia sac.
We repaired the encephalocele using a combined microsurgical and endoscopic multidisciplinary approach working through transcranial, transnasal, and transpalatal corridors. The procedure was completed in a single stage, during which the midline cleft lip was also repaired. The child made an excellent neurological and aesthetic recovery with preservation of pituitary and hypothalamic function, without evidence of CSF fistula.
The authors describe a novel multidisciplinary technique for treating a giant sphenoethmoidal encephalocele containing eloquent brain. The cleft lip was also repaired at the same time. The ability to work through multiple corridors can enhance the safety and efficacy of an often-treacherous operative endeavor.

UNASSIGNED: Report a series of cases in which patients have concomitant superior semicircular canal dehiscence (SSCD) and a dehiscent tegmen tympani with Dural contact to the malleus head (DCMH).
UNASSIGNED: An analysis of radiologic and audiologic data in 4 patients who presented with SSCD and DCMH at a tertiary care institution. A pertinent literature review was performed.
UNASSIGNED: Four patients (5 ears) had SSCD and DCMH. In 3 patients with unilateral DCMH, the mean maximum air-bone gap was 15 dB in the ear with DCMH compared to 50 dB in the ear without DCMH. Of the 5 ears with DCMH, the mean air conduction threshold at 250 Hz was 17 dB compared to 42 dB in the 3 ears without DCMH.
UNASSIGNED: We report the findings of DCMH in a series of 4 patients with bilateral SSCD. This limited series suggests that ears with SSCD and DCMH have less of an air-bone gap than would be expected, as 1 would expect an additive effect of DCMH and SSCD on the air-bone gap.

UNASSIGNED: Dopamine agonist-induced cerebrospinal fluid (CSF) rhinorrhea is an uncommon treatment-related complication arising in 6.1% of prolactinoma patients treated with dopamine agonists. Locally invasive prolactinomas may create CSF fistulae through formation of dural and osseous skull base defects. Tumor shrinkage secondary to dopamine agonist therapy unmasks skull base defects, thus inducing CSF rhinorrhea. In these cases, repair of the leak may be achieved through collaborative surgical intervention by rhinologists and neurosurgeons. Multiple variables have been investigated as potential contributors to the risk of CSF rhinorrhea development in medically treated prolactinoma patients, with little consensus.
UNASSIGNED: The primary aim of our study was the characterization of risk factors for CSF rhinorrhea development following dopamine agonist treatment.
UNASSIGNED: A systematic review of the literature was conducted to identify cases of CSF rhinorrhea following dopamine agonist treatment of prolactinoma. The clinical history, radiographic findings and treatment outcomes are discussed.
UNASSIGNED: Fifty-four patients with dopamine agonist-induced CSF rhinorrhea were identified across 23 articles published from 1979 to 2019. Description of diagnostic imaging [computed tomography (CT)/magnetic resonance imaging (MRI)] was not provided for 18/54 subjects. For the 36 cases that described prolactinoma appearance on CT or MRI, invasion of the cavernous sinuses was reported in 13 (36.1%) and invasion of the sphenoid sinus was reported in 18 (50%).
UNASSIGNED: Based on our systematic review, we propose that CT findings of osseous erosion of the sella or the anterior skull base may predict dopamine agonist-induced CSF rhinorrhea. We recommend obtaining a thin-slice CT of the sinuses in cases with MRI evidence of sphenoid involvement.

Introduction Cerebrospinal fluid (CSF) rhinorrhea is the result of a bony defect at the skull base with disruption of the arachnoid, dura mater, and sinonasal mucosa that leads to an active CSF leak and flow of clear fluid from the nose. The endoscopic repair of CSF leaks and skull defects have been used by an increasing number of surgeons and is the standard of care for repairing CSF leaks. Materials and methods We conducted a retrospective study of all cases of CSF leaks managed via the endonasal endoscopic approach from 2010 to 2020 at a tertiary referral hospital of King Fahad Specialist Hospital, Dammam (KFSH-D). Results Over 10 years, 61 procedures were performed on a total of 56 patients (average age, 39.9 years) with 26 spontaneous CSF leaks and 30 traumatic CSF leaks. The leak sites were frontal bone in 14% of the cases, the roof of the ethmoid in 25%, the cribriform plate of ethmoid in 39%, and the walls of sphenoid sinus in 21%; multiple site defects were found in eight patients. The defect was localized by high-resolution computed tomography (CT) of the paranasal sinuses and skull base and magnetic resonance imaging (MRI) in all patients. CT cisternography, intrathecal fluorescein injection, and topical application of fluorescein dye were used in patients as required. A combination of free grafts and flaps materials were used in most patients. A middle and inferior turbinate graft was used in 12 patients, a septal cartilage graft in 18 patients, and a pedicled nasoseptal flap in 12 patients. The success rate was 92% after the first closure attempt. A recurrence of CSF leaks was observed in four patients. The mean hospitalization time was 6.5 days. The postoperative follow-up period ranged from one year to 10 years with a mean postoperative follow-up time of three years. Conclusions The endonasal endoscopic approach is the current standard of care for repairing most CSF leaks and skull base defects. We have had an excellent experience with endonasal endoscopic CSF leak repair, with high success rates and low morbidity. Our results support the effectiveness and safety of this technique and should encourage otolaryngologists to apply the procedure in cases of CSF leak.

BACKGROUND: Cerebrospinal fluid leak (CSFL) repair simulation models are scarce; however, these models are valuable tools for skull base reconstruction surgery training.
OBJECTIVE: This study aims to assess the face, content, and construct validity of a CSFL repair simulation model.
METHODS: Eight novices (residents- PGY3) and eight experts have performed skull base reconstruction in multiple sites in twelve human cadaveric heads in simulated surgical environment. The experts completed a post-study 21-item questionnaire to assess the face and content validity. The performances of the participants were recorded and scored by two independent investigators who were blinded to the participant\'s level. Global Rating Scale of Operative Performance (GRSOP) and a Specific Skull Base Reconstruction Checklist (SBRC) were used to score the performances.
RESULTS: The responses from the expert group for the 21-item questionnaire were high for all items (4.13-4.88 out of 5). The internal consistency reliability of the questionnaire and the intraclass correlation, which was derived by Cronbach\'s Alpha, were 0.913 and 0.941 respectively. Differences in construct validity between the two groups were statistically significant for both the GRSOP and SBRS (P-value < 0.001).
CONCLUSIONS: We demonstrated the face, content, and construct validity of the CSFL repair simulation model, which facilitates the acquisition of technical skills necessary for skull base reconstruction surgery. The model includes realistic features that make it useful in educational courses.

Cerebrospinal fluid (CSF) leakage after penetrating skull base injury is relatively rare compared with close head injuries involving skull base fractures.
We report the case of a 65-year-old man who had presented with epistaxis and serous rhinorrhea. When he had fallen to the ground near his bee boxes, a garden pole had poked into his right nostril. He had instantly removed the pole from his nostril himself. However, immediately after removal of the pole, he had developed nasal bleeding and serous rhinorrhea. He then drove to our emergency room. Computed tomography showed pneumocephalus with a minor cerebral contusion in the left frontal lobe and a penetrating injury in the left anterior skull base. His CSF leakage had not resolve spontaneously within 1 week after the injury with strict bed rest. We repaired the CSF leakage using a fat (adipose tissue)-on-fascia autograft plug and caulked the defect in the anterior skull base with the fat-on-fascia graft (FFG) plug through the left nostril with endoscopic guidance. The CSF rhinorrhea was successfully controlled. Intranasal local application of fluorescein aided in the detection of the direction of flow of the CSF leakage.
Endonasal endoscopic caulking of a skull base defect using an FFG plug can be useful to treat CSF leakage due to the localized skull base defect, especially in the coronavirus disease 2019 pandemic. It is simple, inexpensive, and timesaving. It requires no special skills nor sophisticated instruments that can cause aerosolization, reducing the risk of infection during the surgery.