Strategy and Technique of Endonasal Endoscopic Bony Decompression and Selective Tumor Removal in Symptomatic Skull Base Meningiomas of the Cavernous Sinus and Meckel's Cave.

BACKGROUND: Parasellar meningiomas involving the cavernous sinus and Meckel's cave pose a management challenge because of invasion around neurovascular structures and the pituitary gland. The management options range from aggressive resection to focused radiotherapy alone. We present a strategy for these tumors that includes endonasal bony decompression, partial tumor removal, and stereotactic radiotherapy (SRT) in select cases. METHODS: The tumor location, previous treatments, cranial neuropathies, pituitary dysfunction, tumor control rates, use of stereotactic radiosurgery, SRT, and complications were retrospectively evaluated. RESULTS: Twenty patients (age range, 43-81 years; 65% women; 90% with World Health Organization grade I; median follow-up, 57 months; 14 without previous debulking and RT; 6 with previous debulking and RT) underwent endonasal bony decompression and partial tumor removal. The most common tumor locations were cavernous sinus (95%), Meckel's cave (95%), sella (75%), petroclival (60%), and optic canal/orbit (30%). Three patients with large meningiomas underwent staged transcranial and endonasal debulking. Of the 14 patients without previous debulking and RT, 11 had undergone postoperative SRT, with tumor shrinkage in 3 (27%). At the last follow-up examination, for these 14 patients and the 6 patients who had undergone previous surgery and RT, tumor control was 100% and 33% (P < 0.001) and the cranial neuropathies had improved in 57% and 33%, respectively. Major complications occurred in 2 patients: a permanent sixth cranial nerve palsy and cerebrospinal fluid leakage requiring reoperation. CONCLUSIONS: Endonasal bony decompression and selective tumor removal, followed by SRT, appears to be a reasonable treatment option for most previously untreated parasellar meningiomas. For patients who have undergone previous debulking and RT, new targeted treatment strategies are needed.

Evaluation of Non-Watertight Dural Reconstruction with Collagen Matrix Onlay Graft in Posterior Fossa Surgery.

OBJECTIVE: Many surgeons advocate for watertight dural reconstruction after posterior fossa surgery given the significant risk of cerebrospinal fluid (CSF) leak. Little evidence exists for posterior fossa dural reconstruction utilizing monolayer collagen matrix onlay graft in a non-watertight fashion. Our objective was to report the results of using collagen matrix in a non-watertight fashion for posterior fossa dural reconstruction. METHODS: We conducted a retrospective review of operations performed by the senior author from 2004-2011 identified collagen matrix (DuraGen) use in 84 posterior fossa operations. Wound complications such as CSF leak, infection, pseudomeningocele, and aseptic meningitis were noted. Fisher's exact test was performed to assess risk factor association with specific complications. RESULTS: Incisional CSF leak rate was 8.3% and non-incisional CSF leak rate was 3.6%. Incidence of aseptic meningitis was 7.1% and all cases resolved with steroids alone. Incidence of palpable and symptomatic pseudomeningocele in follow-up was 10.7% and 3.6% respectively. Postoperative infection rate was 4.8%. Previous surgery was associated with pseudomeningocele development (p<0.05). CONCLUSION: When primary dural closure after posterior fossa surgery is undesirable or not feasible, non-watertight dural reconstruction with collagen matrix resulted in incisional CSF leak in 8.3%. Incidence of pseudomeningocele, aseptic meningitis, and wound infection were within acceptable range. Data from this study may be used to compare alternative methods of dural reconstruction in posterior fossa surgery.

Endonasal Endoscopic Management of Parasellar and Cavernous Sinus Meningiomas.

The management of cavernous sinus and invasive parasellar meningiomas often requires a multimodality treatment approach. Early attempts at complete or near-complete removal of parasellar meningiomas involving the cavernous sinus, Meckel cave, clivus, and sella using anterolateral or lateral skull base approaches were typically unsuccessful and yielded high rates of new cranial neuropathy and other complications. This article presents a strategy of endonasal endoscopic parasellar skull base bony decompression and limited tumor removal followed by stereotactic radiotherapy, stereotactic radiosurgery, or observation. Patient selection, technical nuances, potential complications, and initial outcomes in a small series of patients are discussed.

Impact of selective pituitary gland incision or resection on hormonal function after adenoma or cyst resection.

OBJECTIVE: With the resection of pituitary lesions, the anterior pituitary gland often obstructs transsphenoidal access to the lesion. In such cases, a gland incision and/or partial gland resection may be required to obtain adequate exposure. We investigate this technique and determine the associated risk of post-operative hypopituitarism. METHODS: All patients who underwent surgical resection of a pituitary adenoma or Rathke cleft cyst (RCC) between July 2007 and January 2013 were analyzed for pre- and post-operative hormone function. The cohort of patients with gland incision/resection were compared to a case-matched control cohort of pituitary surgery patients. Total hypophysectomy patients were excluded from outcome analysis. RESULTS: Of 372 operations over this period, an anterior pituitary gland incision or partial gland resection was performed in 79 cases (21.2 %). These include 53 gland incisions, 12 partial hemi-hypophysectomies and 14 resections of thinned/attenuated anterior gland. Diagnoses included 64 adenomas and 15 RCCs. New permanent hypopituitarism occurred in three patients (3.8 %), including permanent DI (3) and growth hormone deficiency (1). There was no significant difference in the rate of worsening gland dysfunction nor gain of function. Compared to a control cohort, there was a significantly lower incidence of transient DI (1.25 vs. 11.1 %, p = 0.009) but no significant difference in permanent DI (3.8 vs. 4.0 %) in the gland incision group. CONCLUSION: Selective gland incisions and gland resections were performed in over 20 % of our cases. This technique appears to minimize traction on compressed normal pituitary gland during removal of large lesions and facilitates better visualization and removal of cysts, microadenomas and macroadenomas.

The expanding role of the endonasal endoscopic approach in pituitary and skull base surgery: A 2014 perspective.

BACKGROUND: The past two decades have been the setting for remarkable advancement in endonasal endoscopic neurosurgery. Refinements in camera definition, surgical instrumentation, navigation, and surgical technique, including the dual surgeon team, have facilitated purely endonasal endoscopic approaches to the majority of the midline skull base that were previously difficult to access through the transsphenoidal microscopic approach. METHODS: This review article looks at many of the articles from 2011 to 2014 citing endonasal endoscopic surgery with regard to approaches and reconstructive techniques, pathologies treated and outcomes, and new technologies under consideration. RESULTS: Refinements in approach and closure techniques have reduced the risk of cerebrospinal fluid leak and infection. This has allowed surgeons to more aggressively treat a variety of pathologies. Four main pathologies with outcomes after treatment were identified for discussion: pituitary adenomas, craniopharyngiomas, anterior skull base meningiomas, and chordomas. Within all four of these tumor types, articles have demonstrated the efficacy, and in certain cases, the advantages over more traditional microscope-based techniques, of the endonasal endoscopic technique. CONCLUSIONS: The endonasal endoscopic approach is a necessary tool in the modern skull base surgeon's armamentarium. Its efficacy for treatment of a wide variety of skull base pathologies has been repeatedly demonstrated. In the experienced surgeon's hands, this technique may offer the advantage of greater tumor removal with reduced overall complications over traditional craniotomies for select tumor pathologies centered near the midline skull base.

Primary Hodgkin lymphoma of the central nervous system.

Primary involvement of the central nervous system by Hodgkin lymphoma is rare; most cases represent metastases. We report a primary Hodgkin lymphoma presenting in the cerebellum of a 77-year-old man and review the literature on primary Hodgkin lymphoma of the central nervous system.

Mid-term results of endovascular coiling of wide-necked aneurysms using double stents in a Y configuration.

BACKGROUND: Double stenting in a Y configuration may be used to treat a subset of wide-necked aneurysms not amenable to reconstruction with a single stent. OBJECTIVE: We studied the feasibility, safety, and mid-term angiographic outcome of patients treated using this technique. METHODS: A retrospective review was undertaken of all coil embolizations of wide-necked aneurysms using double stents in a Y configuration. RESULTS: Nineteen patients were identified from 2002 to 2010 (14 women, 5 men) with a mean age of 57.4 years. Stents were deployed in a Y configuration achieving complete occlusion (5/19), residual neck (5/19), and residual aneurysm filling (9/19). Angiographic follow-up was available for a mean of 16 months, and clinical follow up was available for a mean of 21.4 months. The incidence of complications at the initial treatment was 6 of 19 (31.6%), and delayed thromboembolic complications occurred in 2 of 19 (10.5%). An angiographic neck recurrence requiring retreatment developed in only 1 of the patients in whom complete occlusion was obtained with the initial treatment. Spontaneous thrombosis and complete occlusion on follow-up imaging were found in 6 patients in whom initial neck or aneurysm filling was observed. Ultimately, 12 of the aneurysms (63.2%) were completely occluded on follow-up angiography. CONCLUSION: Y-stent reconstruction enables the endovascular management of otherwise complex, wide-necked cerebral aneurysms and can be performed safely in experienced hands with satisfactory mid-term results, even in cases requiring retreatment.