Optimal Multiple-Layered Anterior Skull Base Reconstruction Using a 360° Suturing Technique

Trans-Defect Underlay Watertight Duraplasty for Traumatic Anterior Skull Base Dural Defect: Technical Report

BACKGROUND

Watertight duraplasty is essential for surgical management of traumatic anterior skull base (ASB) dural defect but challenging in the deep and narrow operative corridor. Here, the authors report a trans-defect underlay watertight duraplasty (TDUWD) technique for traumatic ASB dural defect.

METHODS

TDUWD was performed by inserting a free pericranium graft under the dural defect. The diameter of the pericranium graft was larger than the dural defect. The pericranium graft was sutured to the dural defect watertightly in an "inside-to-outside" direction, with the needle not penetrating the inner layer of pericranium graft. The pedicled pericranium flap was used as a second layer of reconstruction. The characteristics, complications, and outcomes of patients who received TDUWD are reported.

RESULTS

A total of 29 patients received TDUWD. Immediate postoperative cessation of cerebrospinal fluid (CSF) leak occurred in 28 patients. One patient recovered after lumber drainage. No patient needed a second operation or reported delayed recurrence of CSF leak. No complication related to the surgical technique was observed.

CONCLUSIONS

Use of TDUWD for traumatic ASB dural defect results in an immediate, 1-stage, and definitive correction of CSF leak and seems to be simple, safe, and reliable for large and deeply located dural defects.

The impact of multidisciplinary approaches on the outcomes of olfactory neuroblastoma treated with postoperative radiotherapy

BACKGROUND

We investigated the outcomes of postoperative radiation therapy for olfactory neuroblastoma (ONB) and our cross-departmental collaboration to enhance the effectiveness of cancer treatment.

METHODS

We retrospectively evaluated 22 patients with ONB who underwent postoperative radiotherapy after tumor resection. En bloc resection was performed; pathology specimens were prepared in coronal sections; and irradiation fields were determined after discussion with radiation oncologists, head and neck surgeons, and pathologists.

RESULTS

The overall survival and local control rates were 95.5% and 100%, respectively, at a median 37-month follow-up. The 3- and 5-year disease-free survival (DFS) rates were 64.4% and 56.3%, respectively. Of the 22 patients, 9 (8 Kadish C and 1 Kadish B) had disease recurrence. Of the nine patients, five had positive margins and two had closed margins; cervical lymph node recurrence occurred in six, and distant metastasis with or without cervical lymph node recurrence occurred in three. DFS analysis of risk factors showed no statistically significant differences, but positive margins were a significant recurrence factor in multivariate analysis.

CONCLUSIONS

The local control rate of ONB treated with postoperative radiation therapy was 100%. This may be attributed to cross-departmental cooperation between head and neck surgeons, pathologists, and radiation oncologists, which resulted in accurate matching of CT images for treatment planning with the location of the tumor and positive margins. Longer follow-up periods are required to evaluate the effectiveness of our strategy.

Simple and safe resection of the crista galli

A critical procedure in the transcribriform approach is the resection of the crista galli. However, the standard technique for crista galli resection has several disadvantages. We reviewed the cases of patients with olfactory neuroblastomas who underwent an endoscopic endonasal transcribriform approach using a newly developed technique for crista galli resection. We performed a cadaveric study to measure the superior accessibility limits using the proposed method. We included 38 patients with olfactory neuroblastomas in this study. The tumor invaded the posterior crista galli in four patients. The anterior end of the crista galli was not invaded by the tumor. Our cadaveric study showed that the dura was approachable to the point that was 7.4 ± 1.3 mm superior and 23.2 ± 7.2 mm lateral to the foramen cecum following crista galli removal. By resecting the crista galli in advance, manipulation of the superior dura became feasible.