Browse

You are looking at 1 - 4 of 4 items for :

  • Neurosurgical Focus x
  • Refine by Access: all x
  • By Author: Jyung, Robert W. x
Clear All
Free access

James K. Liu and Robert W. Jyung

Cholesterol granulomas are cystic lesions that typically arise in the petrous apex as a result of an inflammatory giant-cell reaction to cholesterol crystal deposits that are formed when normal aeration and drainage of temporal bone air cells become occluded resulting in transudation of blood into the petrous air cells. Surgical strategies include simple cyst decompression, radical excision of the cyst wall, or fenestration and drainage with silastic tubing. The authors present a giant cholesterol granuloma compressing the cerebellopontine angle and brainstem in a 35 year-old male who presented with progressive facial nerve weakness, sensorineural hearing loss, and vertigo. A combined transmastoid middle fossa extradural approach was performed to remove the cyst contents and decompress the brain-stem. A near total excision of the cyst wall was achieved with a small remnant adherent to the posterior fossa dura. Two separate silastic catheters were placed into the cyst cavity to provide “dual exhaust” drainage. One catheter drained the cyst cavity into the sphenoid sinus via a window made in the anteromedial triangle between V1 and V2. The second catheter drained the cyst cavity into the mastoidectomy cavity and middle ear. Postoperative MRI demonstrated regression of the cyst and excellent decompression of the brainstem. The patient experienced return of normal facial nerve function while hearing loss remained unchanged. He remained free of recurrence at 4 years postoperatively. The theoretical advantages of cyst wall removal combined with dual catheter drainage are longer term patency of cyst drainage and decrease of cyst recurrence. In this operative video atlas report, we describe the step-by-step technique and illustrate the operative nuances and surgical pearls to safely and efficiently perform the “dual exhaust” catheter drainage and resection of a giant cholesterol granuloma via a combined transmastoid middle fossa approach.

The video can be found here: http://youtu.be/iZpYBP26ghA.

Free access

James K. Liu and Robert W. Jyung

Large acoustic neuromas, greater than 3 cm, can be technically challenging tumors to remove because of their intimate relationship with the brainstem and surrounding cranial nerves. Successful tumor resection involves functional preservation of the facial nerve and neurovascular structures. The translabyrinthine approach is useful for surgical resection of acoustic neuromas of various sizes in patients with poor preoperative hearing. The presigmoid surgical corridor allows direct exposure of the tumor in the cerebellopontine angle without any fixed cerebellar retraction. Early identification of the facial nerve at the fundus facilitates facial nerve preservation. Large acoustic tumors can be readily removed with a retractorless translabyrinthine approach using dynamic mobilization of the sigmoid sinus. In this operative video atlas report, the authors demonstrate their operative nuances for resection of a large acoustic neuroma via a translabyrinthine approach using a retractorless technique. Facial nerve preservation is achieved by maintaining a plane of dissection between the tumor capsule and the tumor arachnoid so that a layer of arachnoid protects the blood supply to the facial nerve. Multilayered closure is achieved with a fascial sling technique in which an autologous fascia lata graft is sutured to the dural defect to suspend the fat graft in the mastoidectomy defect. We describe the step-by-step technique and illustrate the operative nuances and surgical pearls to safely and efficiently perform the retractorless translabyrinthine approach, tumor resection, facial nerve preservation, and multi-layered reconstruction of the skull base dural defect to prevent postoperative cerebrospinal fluid leakage.

The video can be found here: http://youtu.be/ros98UxqVMw.

Full access

James K. Liu, Smruti K. Patel, Amanda J. Podolski, and Robert W. Jyung

Reconstruction of presigmoid dural defects after resection of acoustic neuromas via the translabyrinthine approach is paramount to prevent postoperative CSF leakage. However, primary dural reapproximation and achieving a watertight closure of the dural defect in this anatomical region are quite difficult. Standard closure techniques after the translabyrinthine approach often involve packing an abdominal fat graft that plugs the dural defect and mastoidectomy cavity. This technique, however, may pose the risk of direct compression of the fat graft on the facial nerve and brainstem. Nonetheless, even with the evolution in dural repair techniques, postoperative CSF leaks can still occur and provide a route for infection and meningitis. In this report, the authors describe a novel dural “sling” reconstruction technique using autologous fascia lata to repair presigmoid dural defects created after translabyrinthine resection of acoustic neuromas. The fascia lata is sewn to the edges of the presigmoid dural defect to create a sling to suspend the fat graft within the mastoidectomy defect. A titanium mesh plate embedded in porous polyethylene is secured over the mastoidectomy defect to apply pressure to the fat graft. In the authors' experience, this has been a successful technique for dural reconstruction after translabyrinthine removal of acoustic neuromas to prevent postoperative CSF leakage. There were no cases of CSF leakage in the first 8 patients treated using this technique. The operative details and preliminary results of this technique are presented.

Full access

Richard F. Schmidt, Zain Boghani, Osamah J. Choudhry, Jean Anderson Eloy, Robert W. Jyung, and James K. Liu

With the relatively recent increase in the use of MRI techniques, there has been a concurrent rise in the number of vestibular schwannomas (VSs) detected as incidental findings. These incidental VSs may be prevalent in up to 0.02%–0.07% of individuals undergoing MRI and represent a significant portion of all diagnosed VSs. The management of these lesions poses a significant challenge for practitioners. Most incidental VSs tend to be small and associated with minimal symptoms, permitting them to be managed conservatively at the time of diagnosis. However, relatively few indicators consistently predict tumor growth and patient outcomes. Furthermore, growth rates have been shown to vary significantly over time with a large variety of long-term growth patterns. Thus, early MRI screening for continued tumor growth followed by repeated MRI studies and clinical assessments throughout the patient's life is an essential component in a conservative management strategy. Note that tumor growth is typically associated with a worsening of symptoms in patients who undergo conservative management, and many of these symptoms have been shown to significantly impact the patient's quality of life. Specific indications for the termination of conservative management vary across studies, but secondary intervention has been shown to be a relatively safe option in most patients with progressive disease. Patients with incidental VSs will probably qualify for a course of conservative management at diagnosis, and regular imaging combined with the expectation that the tumor and symptoms may change at any interval is crucial to ensuring positive long-term outcomes in these patients. In this report, the authors discuss the current literature pertaining to the prevalence of incidental VSs and various considerations in the management of these lesions. It is hoped that by incorporating an understanding of tumor growth, patient outcomes, and management strategies, practitioners will be able to effectively address this challenging disease entity.