In-Hospital Costs Associated With an Expanded Endonasal Approach to Anterior Skull Base Tumors

Objective: To determine in-hospital costs associated with performing an EEA to anterior skull base pathology and to identify drivers of cost variability for patients undergoing endoscopic anterior skull base surgery. Methods: All endoscopic anterior skull base surgeries performed over a period from January 1st, 2015 to October 24th, 2017 were evaluated. The electronic medical record was reviewed for patient factors, tumor characteristics, and cost variables associated with each hospital stay and univariate analysis was performed using Stata software. Results: An EEA was associated with an average total in-hospital cost of $44 545. Compared to patients undergoing a transsphenoidal approach to pituitary tumor resection, EEA patients incurred higher in-hospital costs across all variables including a total cost increase of $15 921 (95% confidence interval $5720-26 122, P = .002). Univariate analysis of all endoscopic anterior skull base surgery patients showed a cost increase of $30 616 associated with post-operative cerebrospinal fluid (CSF) leak ($10 420-50 811, P = .004), $14 610 with post-operative diabetes insipidus (DI) ($4610-24 609, P = .004), and $11 522 with African-American patients relative to Caucasian patients ($3049-19 995, P = .008). Conclusions: Patients who undergo endoscopic EEA for resection of anterior skull base tumors typically incur greater in-hospital costs than patients undergoing a standard TSA. Post-operative complications such as CSF leak and DI, as well as ethnicity, are significant drivers of cost-variability.

An Endoscopic Endonasal Nasopharyngectomy with Posterolateral Extension

Background Invasion depth influences the choice for extirpation of nasopharyngeal malignancies. This study aims to validate the feasibility of endoscopic endonasal resection of lesions with a posterolateral invasion. As a secondary goal, the study intends to propose a classification system of endoscopic endonasal nasopharyngectomy determined by the depth of posterolateral invasion. Methods Eight cadaveric specimens (16 sides) underwent progressive nasopharyngectomy using an endoscopic endonasal approach. Resection of the torus tubarius, Eustachian tube (ET), medial pterygoid plate and muscle, lateral nasal wall, and lateral pterygoid plate and muscle were sequentially performed to expose the fossa of Rosenmüller, petroclival region, parapharyngeal space (PPS), and jugular foramen, respectively. Results Technical feasibility of endonasal nasopharyngectomy toward a posterolateral direction was validated in all 16 sides. Nasopharyngectomy was classified into four types as follows: (1) type 1: resection restricted to the posterior or superior nasopharynx; (2) type 2: resection includes the torus tubarius which is suitable for lesions extended into the petroclival region; (3) type 3: resection includes the distal cartilaginous ET, medial pterygoid plate, and muscle, often required for lesions extending laterally into the PPS; And (4) type 4: resection includes the lateral nasal wall, pterygoid plates and muscles, and all the cartilaginous ET. This extensive resection is required for lesions involving the carotid artery or extending to the jugular foramen region. Conclusion Selected lesions with posterolateral invasion into the PPS or jugular foramen is amenable to a resection via expanded endonasal approach. Classification of nasopharyngectomy based on tumor depth of posterolateral invasion helps to plan a surgical approach.

Collision Occurrence of Sinonasal Carcinosarcoma and Pituitary Adenoma: A Case Report and Literature Review.

BACKGROUND: Collision occurrences of sinonasal carcinosarcoma and pituitary adenoma are rarely reported. Sinonasal carcinosarcomas represent rare neoplasms with invasive characteristics and unfavorable prognoses.CASE DESCRIPTION: We present a rare case of a collision occurrence of sinonasal carcinosarcoma and pituitary adenoma in a 45‐year‐old male patient. MRI demonstrated a large mass involving the sellar region, nasal cavity, paranasal sinuses and anterior cranial base. Total surgical resection with a pure endoscopic expanded endonasal approach was performed successfully with neuronavigational assistance. Histopathologic results were a carcinosarcoma in the nasal cavity, paranasal sinuses, and anterior cranial base and a pituitary adenoma in the intrasellar zone. The Ki-67 index of the carcinosarcoma was high (more than 95%). Although the patient received chemotherapy, he died 6 months after surgery because of in situ recurrence and extensive metastatic growth.CONCLUSIONS: Collision occurrences of sinonasal carcinosarcoma and pituitary adenoma are rare events. Such tumor could be removed successfully by neuronavigational guidance with a pure endoscopic expanded endonasal approach. A contralateral nasal septum mucosa flap without tumor invasion can be used as a kind of skull base repair material. A high Ki-67 index may be a biomarker of rapid tumor progression and poor prognosis in such patients.

Abducens Nerve Schwannoma: First Case to Be Treated With an Expanded Endonasal Approach

Abducens nerve schwannomas are incredibly rare, with very few cases being reported previously. Our patient is the first to have been treated through use of an endoscopic endonasal approach. A 61-year-old woman presented with diplopia over a 1-year period. Magnetic resonance imaging identified a 2.8-cm lesion expanding into her right sphenoid sinus. She underwent an endoscopic endonasal approach for histological diagnosis and clearance of the lesion. Intraoperative exploration found the lesion to be originating from Dorello canal. Histological analysis confirmed a benign schwannoma. Following a multidisciplinary case review, we have followed a conservative approach and she remains well on radiological surveillance. In patients presenting with a sixth nerve palsy/paresis and a concomitant sphenoid lesion, clinicians should consider an abducens schwannoma as a possible diagnosis.

Clinical features and operative technique of transinfundibular craniopharyngioma

OBJECTIVETransinfundibular craniopharyngioma (TC) is one of the 4 subtypes of suprasellar craniopharyngioma. In this study, the authors analyzed the clinical features of and operative technique for TC.METHODSA total of 95 consecutive cases of suprasellar craniopharyngioma that had been resected via the endoscopic expanded endonasal approach were retrospectively reviewed. Patients were divided into 2 groups: 34 in the TC group and 61 in the nontransinfundibular craniopharyngioma (NC) group. Clinical and radiographic features, intraoperative findings, histopathological and genetic findings, and surgical outcomes were analyzed and compared between groups.RESULTSCompared with NC, TC was mostly seen in adult patients (97.1%); it was rare in children (2.9%). Clinical presentations tended toward headache, hydrocephalus, and diabetes insipidus. The relatively smaller volume, midline location (consistent with the stalk position), unidentifiable stalk, no shift of the third ventricle, and greater likelihood to involve the third ventricle and cause hydrocephalus were the characteristic features of TC in the preoperative MRI study. According to the degree of vertical extension of the tumor, the 34 TCs could be classified into 3 subtypes: type 1, entity was limited to stalk (n = 2, 5.9%); type 2, tumor extended up to the third ventricle (type 2a) or down to the subdiaphragmatic cavity (type 2b) (n = 23, 67.6%); and type 3, tumor extended in both directions (n = 9, 26.5%). For TC resection, the chiasm–pituitary corridor, lamina terminalis corridor, and pituitary corridor could be used separately or jointly. Most of the TCs originated from the infundibulum–tuber cinereum, grew within and along the long axis of the infundibulum, and the pituitary stalk was not usually preserved in TCs (20.6%), whereas the rate of preservation was higher (80.3%) in NCs. Bilateral hypothalamic injury was found in nearly all TCs if radical resection was performed, whereas the relationship between NCs and hypothalamus was either compression (32.8%) or unilateral invasion (67.2%). Meanwhile, the postoperative endocrine and neuropsychological function outcomes in patients with TC were worse than in patients with NC. The genetic analysis with whole-exome sequencing studies showed no differential mutations of CTNNB1 (β-catenin) and BRAF (V600E) between TC and NC subtypes, but there was a difference between adamantinomatous craniopharyngioma and papillary craniopharyngioma.CONCLUSIONSTC is a special subtype of suprasellar craniopharyngioma, which is remarkably different from NC. Identification of this type of tumor preoperatively is essential for the planning of appropriate surgical approach and degree of excision.

Investigation of the Effect of Process Parameters on Bone Grinding Performance Based on On-Line Measurement of Temperature and Force Sensors

This study investigates the effect of process parameters on neurosurgical bone grinding performance using a miniature surgical diamond wheel. Bone grinding is an important procedure in the expanded endonasal approach for removing the cranial bone and access to the skull base tumor via nasal corridor. Heat and force are generated during the grinding process, which may cause thermal and mechanical damage to the adjacent tissues. This study investigates the effect of grinding process parameters (including the depth of cut, feed rate, and spindle speed) on the bone grinding performance using temperature and force measurement sensors in order to optimize the grinding process. An orthogonal experimental design with a standard orthogonal array, L9 (33), is selected with each parameter in three levels. The experimental results have been statistically analyzed using the range and variance analysis methods in order to determine the importance order of the process parameters. The results indicate that the effect of the cutting depth on the grinding temperature and normal force is the largest, while the effect of the spindle speed on the tangential force is the largest. A high spindle speed would make the temperature rise to a certain extent; however, it significantly reduces the grinding force. At a certain spindle speed, a lower depth of cut and feed rate help to reduce the grinding temperature and force.

Expanded Endonasal Approach for Resection of Extradural Infratemporal Fossa Trigeminal Schwannoma: 2-Dimensional Operative Video

The infratemporal fossa (ITF) is bounded superiorly by the skull base, specifically the greater wing of the sphenoid, which contains foramen ovale. It is bordered posteriorly by the temporal bone, including the petrous portion of the carotid canal, anteriorly by the posterior wall of the maxillary sinus, laterally by the mandible, and medially by the pterygoid body and lateral pterygoid plate.1-3 In this video, we report a case of a rare, exclusively extradural, schwannoma originating from the third division of the trigeminal nerve with a widened foramen ovale at the skull base. The tumor filled the ITF and extended laterally just through the sigmoid notch of the mandible. The patient complained of left cheek and lower jaw numbness and intermittent left jaw spasms. The tumor was deemed appropriate for endoscopic resection. To access the ITF, left-sided endoscopic sinus surgery, a modified endoscopic Denker's approach,4 and posterior nasal septectomy were first performed. A nasoseptal flap was also harvested in case an intraoperative cerebrospinal fluid (CSF) leak required repair. Dissection was carried out through the posterior wall of the maxillary sinus and pterygopalatine fossa to reach the ITF. Tumor resection was achieved through a 2-surgeon, 4-handed approach in which appropriate traction and countertraction were carefully applied to tease the tumor away from the skull base and dehiscent carotid canal. No CSF leak or carotid injury occurred, and the posterior maxillary sinus wall defect was repaired with the nasoseptal flap. The patient did well postoperatively. The patient consented to the procedure in a standard fashion.