Reuse of Nasoseptal Flaps for Endoscopic Endonasal Skull Base Reconstruction.

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.

The lateral transorbital approach to the medial sphenoid wing, anterior clinoid, middle fossa, cavernous sinus, and Meckel's cave: target-based classification, approach-related complications, and intermediate-term ocular outcomes.

OBJECTIVE: The lateral transorbital approach (LTOA) is a relatively new minimal access skull base approach suited for addressing paramedian pathology of the anterior and middle fossa. The authors define target zones for this approach and describe a series of cases with detailed measurements of visual outcomes, including those obtained with exophthalmometry. METHODS: The authors performed a retrospective analysis of a consecutive series of LTOA patients. Seven target zones were identified: 1) the orbit, 2) the lesser sphenoid wing and anterior clinoid, 3) the middle fossa, 4) the lateral wall of the cavernous sinus and Meckel's cave, 5) the infratemporal fossa, 6) the petrous apex, and 7) the anterior fossa. The authors used volumetric analyses of preoperative and postoperative MR and CT imaging data to calculate the volume of bone and tumor removed and to provide detailed ophthalmological, neurological, and cosmetic outcomes. RESULTS: Of the 20 patients in this cohort, pathology was in zone 2 (n = 10), zone 4 (n = 6), zone 3 (n = 2), zone 1 (n = 1), and zone 5 (n = 1). Pathology was meningioma (n = 10), schwannoma (n = 2), metastasis (n = 2), epidermoid (n = 1), dermoid (n = 1), encephalocele (n = 1), adenoma (n = 1), glioblastoma (n = 1), and inflammatory lesion (n = 1). The goal was gross-total resection (GTR) in 9 patients, all of whom achieved GTR. Subtotal resection (STR) was the goal in 8 patients (5 spheno-orbital meningiomas, 1 giant cavernous sinus/Meckel's cave schwannoma, 1 cavernous sinus prolactinoma, and 1 cavernous sinus dermoid), 7 of whom achieved STR and 1 of whom achieved GTR. The goal was biopsy in 2 patient and repair of encephalocele in 1. Visual acuity was stable or improved in 18 patients and worse in 2. Transient early postoperative diplopia, ptosis, eyelid swelling, and peri-orbital numbness were common. All 9 patients with preoperative diplopia improved at their last follow-up. Seven of 8 patients with preoperative exophthalmos improved after surgery (average correction of 64%). There were no cases of clinically significant (> 2 mm) postoperative enophthalmos. The most frequent postoperative complaint was peri-orbital numbness (40%). There was 1 CSF leak. Most patients were satisfied with their ocular (84%-100% of patients provided positive satisfaction-related responses) and cosmetic (75%-100%) outcomes. CONCLUSIONS: The LTOA is a safe minimal access approach to a variety of paramedian anterior skull base pathologies in several locations. Early follow-up revealed excellent resolution of exophthalmos with little risk of clinically significant enophthalmos. Transient diplopia, ptosis, and peri-orbital numbness were common but improved. Careful case selection is critical to ensure good outcome.

Lateral Transorbital Approach for Repair of Lateral Sphenoid Sinus Meningoencephaloceles in Proximity to Foramen Rotundum: Cadaveric Study and Case Report.

BACKGROUND: The repair of lateral sphenoid sinus cerebrospinal fluid leaks is routinely accomplished through the use of the endonasal endoscopic approach (EEA) with a transpterygoidal extension. This approach can incur sinus morbidity, damage to the vidian, palatine and trigeminal nerves, and the contents of the pterygopalatine fossa, particularly if the encephalocele is lateral to the foramen rotundum (FR) and V2. OBJECTIVE: To investigate the use of the lateral transorbital approach (LTOA) as an alternative approach for repair of lateral sphenoid sinus encephaloceles that avoids the potential morbidity of EEA. METHODS: We performed cadaveric dissections of 2 specimens (4 sides) and present one of the first cases of a lateral sphenoid sinus encephalocele repair lateral to the FR in a patient through an ipsilateral LTOA. RESULTS: We find that the LTOA provides a shorter distance to target compared with the EEA (56 vs 89.5 mm, P = .002). The LTOA field of view also affords excellent visualization of both the medial and lateral aspects of V2, whereas the EEA is less effective at exposing lateral to V2, even after sacrifice of the vidian nerve and maximal pterygopalatine fossa content retraction. We report a case of LTOA to repair a meningoencephalocele lateral to V2 in the sphenoid sinus. CONCLUSION: The LTOA to the foramen rotundum is a more direct approach that minimizes the morbidity associated with EEA to repair meningoencephaloceles both medial and lateral to foramen rotundum.

A telemedicine instrument for home monitoring of patients with chronic respiratory diseases.

We developed a telemedicine instrument for home monitoring of subjects with respiratory diseases. The instrument directly measures blood oxygen saturation and pulse rate, but the most relevant aspect is that it also acts as digital recorder of parameters coming from several external instruments (spirometer, capnometer, NIBP device, etc.). It also connects to all pulmonary ventilators. The instrument main board includes five slots, which are used to insert the measuring boards (saturation and ventilation boards) and the interface boards (connecting the external instruments). Depending on patient's needs, only the proper measuring/interface boards are mounted, thus allowing maximum flexibility and cost saving. The instrument has several I/O units, and especially an internal modem for direct connection to the Internet through TCP/IP protocol. The instrument was extensively tested, and preliminary trials were performed over fifteen patients with amyotrophic lateral sclerosis.

Qualitative and quantitative analyses of protein phosphorylation in naive and stimulated mouse synaptosomal preparations.

Activity-dependent protein phosphorylation is a highly dynamic yet tightly regulated process essential for cellular signaling. Although recognized as critical for neuronal functions, the extent and stoichiometry of phosphorylation in brain cells remain undetermined. In this study, we resolved activity-dependent changes in phosphorylation stoichiometry at specific sites in distinct subcellular compartments of brain cells. Following highly sensitive phosphopeptide enrichment using immobilized metal affinity chromatography and mass spectrometry, we isolated and identified 974 unique phosphorylation sites on 499 proteins, many of which are novel. To further explore the significance of specific phosphorylation sites, we used isobaric peptide labels and determined the absolute quantity of both phosphorylated and non-phosphorylated peptides of candidate phosphoproteins and estimated phosphorylation stoichiometry. The analyses of phosphorylation dynamics using differentially stimulated synaptic terminal preparations revealed activity-dependent changes in phosphorylation stoichiometry of target proteins. Using this method, we were able to differentiate between distinct isoforms of Ca2+/calmodulin-dependent protein kinase (CaMKII) and identify a novel activity-regulated phosphorylation site on the glutamate receptor subunit GluR1. Together these data illustrate that mass spectrometry-based methods can be used to determine activity-dependent changes in phosphorylation stoichiometry on candidate phosphopeptides following large scale phosphoproteome analysis of brain tissue.