Jacob B. Archer

Surgical anatomy and utility of pedicled vascularized tissue flaps for multilayered repair of skull base defects.

OBJECT The objective of this study was to describe the surgical anatomy and technical nuances of various vascularized tissue flaps. METHODS The surgical anatomy of various tissue flaps and their vascular pedicles was studied in 5 colored silicone-injected anatomical specimens. Medical records were reviewed of 11 consecutive patients who underwent repair of extensive skull base defects with a combination of various vascularized flaps. RESULTS The supraorbital, supratrochlear, superficial temporal, greater auricular, and occipital arteries contribute to the vascular supply of the pericranium. The pericranial flap can be designed based on an axial blood supply. Laterally, various flaps are supplied by the deep or superficial temporal arteries. The nasoseptal flap is a vascular pedicled flap based on the nasoseptal artery. Patients with extensive skull base defects can undergo effective repair with dual flaps or triple flaps using these pedicled vascularized flaps. CONCLUSIONS Multiple pedicled flaps are available for reconstitution of the skull base. Knowledge of the surgical anatomy of these flaps is crucial for the skull base surgeon. These vascularized tissue flaps can be used effectively as single or combination flaps. Multilayered closure of cranial base defects with vascularized tissue can be used safely and may lead to excellent repair outcomes.

Management of Intracranial Meningiomas Using Keyhole Techniques

Background: Keyhole craniotomies are increasingly being used for lesions of the skull base. Here we review our recent experience with these approaches for resection of intracranial meningiomas. Methods: Clinical and operative data were gathered on all patients treated with keyhole approaches by the senior author from January 2012 to June 2013. Thirty-one meningiomas were resected in 27 patients, including 9 supratentorial, 5 anterior fossa, 7 middle fossa, 6 posterior fossa, and 4 complex skull base tumors. Twenty-nine tumors were WHO Grade I, and 2 were Grade II. Results: The mean operative time was 8 hours, 22 minutes (range, 2:55-16:14) for skull-base tumors, and 4 hours, 27 minutes (range, 1:45-7:13) for supratentorial tumors. Simpson Resection grades were as follows: Grade I = 8, II = 8, III = 1, IV = 15, V = 0. The median postoperative hospital stay was 4 days (range, 1-20 days). In the 9 patients presenting with some degree of visual loss, 7 saw improvement or complete resolution. In the 6 patients presenting with cranial nerve palsies, 4 experienced improvement or resolution of the deficit postoperatively. Four patients experienced new neurologic deficits, all of which were improved or resolved at the time of the last follow-up. Technical aspects and surgical nuances of these approaches for management of intracranial meningiomas are discussed. Conclusions: With careful preoperative evaluation, keyhole approaches can be utilized singly or in combination to manage meningiomas in a wide variety of locations with satisfactory results.

Extensive Anterior Cranial Base Fractures: Anatomic and Surgical Description of Combination Flaps

Introduction: Traditionally, cerebrospinal fluid (CSF) fistula repair following anterior skull base fractures has been accomplished with the use of exclusive anterior-based pericranial flaps. Over time, limitations have been identified with this technique. Persistent CSF leak rates following initial repairs are 12.5 to 17%, and could potentially be contributed to compromise blood supply resulting from initial cranial insult. In addition, glabellar tissue defects from placement of these flaps can result in poor cosmesis. The limited posterior reach of these flaps can hinder repairs in fractures with a substantial posterior extent. This has led to the addition of lateral temporoparital fascial flap and nasoseptal flap to our repair techniques. Methods: Retrospective chart review was preformed of patients with CSF fistula from anterior skull base fractures that were repaired utilizing any combination of anterior pericranial flap, lateral temporoparietal fascial flap, and/or nasoseptal flap. Nasoseptal flap repairs were utilized primarily during initial repair or as a salvage therapy in patients with persistent leaks following an initial repair. Additional anatomic studies were preformed using cadaveric specimen to help with flap design. Results: A total of 10 patients were identified. Nine had fractures extending back to the sphenoid bone, and one had fractures only spanning frontal and ethmoid bones. Nasoseptal flap was utilized as a salvage procedure in three patients. Two cases utilized all three flaps. One patient had combination anterior pericranial and nasoseptal flap, and the other four combined temporoparietal fascial and anterior pericranial flaps. There were no postoperative infections. There were no mortalities and one patient required wound revision for dehiscence. No patient had persistent CSF leak following repair with any combination of flap. Conclusion: Exclusive anterior-based pericranial flaps in comminuted anterior skull based fractures can be supplemented or replaced with temporoparietal fascial flaps and nasoseptal flaps to provide the greatest long-term functional and cosmetic outcome. The combined use of nasoseptal flaps, anterior pericranial flaps, and lateral temporoparietal fascial flaps allow for a comprehensive arsenal in anterior skull base repair and salvage therapy for extensive and severe fractures.