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The history of neurosurgery at the House Clinic in Los Angeles

Gautam U. Mehta and Gregory P. Lekovic

Although most widely known as the birthplace of neuro-otology, the House Clinic in Los Angeles has been the site of several major contributions to the field of neurosurgery. From the beginning of the formation of the Otologic Medical Group in 1958 (later renamed the House Ear Clinic), these contributions have been largely due to the innovative and collaborative work of neurosurgeon William E. Hitselberger, MD, and neuro-otologist William F. House, MD, DDS. Together they were responsible for the development and widespread adoption of the team approach to skull-base surgery. Specific neurosurgical advances accomplished at the House Clinic have included the first application of the operative microscope to neurosurgery, the application of middle fossa and translabyrinthine approaches for vestibular schwannoma, and the development of combined petrosal, retrolabyrinthine, and other alternative petrosal approaches and of hearing preservation surgery for vestibular schwannoma. The auditory brainstem implant, invented at the House Clinic in 1979, was the first ever successful application of central nervous system neuromodulation for restoration of function. Technological innovations at the House Clinic have also advanced neurosurgery. These include the first video transmission of microsurgery, the first suction irrigator, the first debulking instrument for tumors, and the House-Urban retractor for middle fossa surgery.

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Use of a flexible hollow-core carbon dioxide laser for microsurgical resection of vestibular schwannomas

Marc S. Schwartz and Gregory P. Lekovic

OBJECTIVE

The CO2 laser has been used on an intermittent basis in the microsurgical resection of brain tumors for decades. These lasers were typically cumbersome to use due to the need for a large, bulky design since infrared light cannot be transmitted via fiber-optic cables. Development of the OmniGuide cable, which is hollow and lined with an omnidirectional dielectric mirror, has facilitated the reintroduction of the CO2 laser in surgical use in a number of fields. This device allows for handheld use of the CO2 laser in a much more ergonomically favorable configuration, holding promise for microneurosurgical applications. This device was introduced into the authors’ practice for use in the microsurgical resection of skull base tumors, including vestibular schwannomas.

METHODS

The authors reviewed the initial 41 vestibular schwannomas that were treated using the OmniGuide CO2 laser during an 8-month period from March 2010 to October 2010. The laser was used for all large tumors, and select medium-sized tumors were treated via both the translabyrinthine and retrosigmoid approaches. The estimated time of tumor resection and estimated blood loss were obtained from operating room records. Data regarding complications, facial nerve and hearing outcomes, and further treatment were collected from hospital and clinic records, MRI reports, and direct review of MR images. Time of resection and blood loss were compared to a control group (n = 18) who underwent surgery just prior to use of the laser.

RESULTS

A total of 41 patients with vestibular schwannomas were surgically treated. The median estimated time of tumor resection was 150 minutes, and the median estimated blood loss was 300 ml. The only operative complication was 1 CSF leak. Thirty-eight patients had normal facial nerve function at late follow-up. The median MRI follow-up was 52 months, and, during that time, only 1 patient required further treatment for regrowth of a residual tumor.

CONCLUSIONS

The OmniGuide CO2 laser is a useful adjunct in the resection of large vestibular schwannomas. This device was used primarily as a cutting tool rather than for tumor vaporization, and it was found to be of most use for very large and/or firm tumors. There were no laser-associated complications, and the results compared favorably to earlier reports of vestibular schwannoma resection.

Open access

Endoscopic closure of the Eustachian tube orifice for refractory lateral skull base cerebrospinal fluid leak using autologous fat graft: illustrative case

Gautam U. Mehta, Nida Fatima, Gregory P. Lekovic, and William H. Slattery

BACKGROUND

Rhinorrhea due to lateral skull base cerebrospinal fluid (CSF) leaks can be a challenge to manage. Multiple strategies exist for treating CSF leaks in this region including direct repair, posterior Eustachian tube packing, and CSF diversion. Endonasal closure of the Eustachian tube has been reported using cerclage and mucosal flaps.

OBSERVATIONS

We present the first reported case of endoscopic autologous fat packing of the Eustachian tube orifice to repair a CSF leak. In this case a 42-year-old woman who underwent middle fossa meningioma resection 20 years ago presented with refractory CSF rhinorrhea despite blind sac closure of the ear canal. This persisted after CSF diversion and only resolved after endoscopic endonasal Eustachian tube closure described herein.

LESSONS

This technique is simple to perform with minimal risk of morbidity. Eustachian tube orifice fat packing may be particularly useful for patients with refractory CSF rhinorrhea with low CSF pressure.

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Multifocal granulocytic sarcoma of the spine mimicking neurofibromatosis Type 2: case report

Gregory P. Lekovic, Marc S. Schwartz, and John L. Go

In this report the authors report on a patient with a very indolent course of granulocytic sarcoma, characterized by steroid-induced remission of spinal and cranial tumors and recurrence over a period of several years. This 24-year-old man with history of leukemia presented with rapid-onset quadriparesis secondary to multiple extraaxial masses of the cervicothoracic spine, from C-5 to T-3, and lumbosacral spine, from L-5 to the coccyx. Although the imaging features were highly suggestive of neurofibromatosis Type 2, the patient's history and clinical course were consistent with granulocytic sarcoma; repeat imaging and, later, needle biopsy definitively established the diagnosis of granulocytic sarcoma. Laminectomy and surgical decompression of the spine were not required and, arguably, could have posed unnecessary risk to the patient. This case illustrates that the successful management of a patient presenting with profound neurological deficits due to intradural spinal cord tumors may sometimes be nonsurgical.

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Atypical tumors of the facial nerve: case series and review of the literature

Lindsey Ross, Doniel Drazin, Paula Eboli, and Gregory P. Lekovic

Object

The authors present a series of 4 patients with rare facial nerve tumors. The relevant literature is reviewed and is discussed regarding diagnostic features, the role of operative management, and surgical approach.

Methods

A retrospective chart review was conducted for patients with tumors of the facial nerve that were treated between 2008 and 2011. Patients undergoing observation with serial MRI and those who were treated with up-front radiosurgery and for whom tissue diagnosis was not available were excluded. In addition, patients with suspected vestibular schwannoma, facial nerve schwannoma, neurofibromatosis Type 2, and metastatic disease were also excluded. The charts of 4 patients (2 men and 2 women) with “atypical” tumors were reviewed and analyzed.

Results

A total of 12 patients with tumors of the facial nerve were identified during the study period. Patient characteristics, preoperative imaging, operative approach, tumor histology, and outcomes are described.

Conclusions

Atypical facial nerve tumors must be distinguished from the more common facial nerve schwannoma. How the authors of this study treat rare facial nerve tumors is based on their experience with the more common facial nerve schwannomas, characterized by a slow progression of symptoms and growth. Less is known about the rare lesions, and thus a conservative approach may be warranted. Open questions include the role of radiosurgery, facial nerve decompression, and indications for resection of tumor and cable grafting for these rare lesions.

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Endoscope-assisted middle fossa craniotomy for resection of inferior vestibular nerve schwannoma extending lateral to transverse crest

Adam N. Master, Daniel S. Roberts, Eric P. Wilkinson, William H. Slattery, and Gregory P. Lekovic

OBJECTIVE

The authors describe their results using an endoscope as an adjunct to microsurgical resection of inferior vestibular schwannomas (VSs) with extension into the fundus of the internal auditory canal below the transverse crest.

METHODS

All patients who had undergone middle fossa craniotomy for VSs performed by the senior author between September 2014 and August 2016 were prospectively enrolled in accordance with IRB policies, and the charts of patients undergoing surgery for inferior vestibular nerve tumors, as determined either on preoperative imaging or as intraoperative findings, were retrospectively reviewed. Age prior to surgery, side of surgery, tumor size, preoperative and postoperative pure-tone average, and speech discrimination scores were recorded. The presence of early and late facial paralysis, nerve of tumor origin, and extent of resection were also recorded.

RESULTS

Six patients (all women; age range 40–65 years, mean age 57 years) met these criteria during the study period. Five of the 6 patients underwent gross-total resection; 1 patient underwent a near-total resection because of a small amount of tumor that adhered to the facial nerve. Gross-total resection was facilitated using the operative endoscope in 2 patients (33%) who were found to have additional tumor visible only through the endoscope. All patients had a House-Brackmann facial nerve grade of II or better in the immediate postoperative period. Serviceable hearing (American Academy of Otolaryngology–Head and Neck Surgery class A or B) was preserved in 3 of the 6 patients.

CONCLUSIONS

Endoscope-assisted middle fossa craniotomy for resection of inferior vestibular nerve schwannomas with extension beyond the transverse crest is safe, and hearing preservation is feasible.

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Translabyrinthine microsurgical resection of small vestibular schwannomas

Marc S. Schwartz, Gregory P. Lekovic, Mia E. Miller, William H. Slattery, and Eric P. Wilkinson

OBJECTIVE

Translabyrinthine resection is one of a number of treatment options available to patients with vestibular schwannomas. Though this procedure is hearing destructive, the authors have noted excellent clinical outcomes for patients with small tumors. The authors review their experience at a tertiary acoustic neuroma referral center in using the translabyrinthine approach to resect small vestibular schwannomas. All operations were performed by a surgical team consisting of a single neurosurgeon and 1 of 7 neurotologists.

METHODS

Data from a prospectively maintained clinical database were extracted and reviewed. Consecutive patients with a preoperative diagnosis of vestibular schwannoma that had less than 1 cm of extension into the cerebellopontine angle, operated on between 2008 and 2013, were included. Patents with neurofibromatosis Type 2, previous treatment, or preexisting facial weakness were excluded. In total, 107 patients were identified, 74.7% of whom had poor hearing preoperatively.

RESULTS

Pathologically, 6.5% of patients were found to have a tumor other than vestibular schwannoma. Excluding two malignancies, the tumor control rates were 98.7%, as defined by absence of radiographic disease, and 99.0%, as defined by no need for additional treatment. Facial nerve outcome was normal (House-Brackmann Grade I) in 97.2% of patients and good (House-Brackmann Grade I–II) in 99.1%. Complications were cerebrospinal fluid leak (4.7%) and sigmoid sinus thrombosis (0.9%), none of which led to long-term sequelae.

CONCLUSIONS

Translabyrinthine resection of small vestibular schwannomas provides excellent results in terms of complication avoidance, tumor control, and facial nerve outcomes. This is a hearing-destructive operation that is advocated for selected patients.

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Endoscopic harvesting of the radial artery for neurovascular bypass

Technical note

L. Fernando Gonzalez, Dixie L. Patterson, Gregory P. Lekovic, Peter Nakaji, and Robert F. Spetzler

Object

The radial artery is a common conduit used for high-flow bypasses. Until now the radial artery has been harvested using a long incision in the forearm that follows the course of the artery. The authors present an endoscopic technique that has been used during coronary bypass surgery but is not yet widespread in the neurosurgical arena.

Methods

From October 2006 to October 2007, the authors used the radial artery as a graft in 6 patients during the treatment of complex cerebral aneurysms. The artery was harvested via an endoscopic technique.

The radial artery was exposed distally at the wrist. Using the VasoView vessel harvesting system, the endoscope was inserted into the arm. The radial artery was dissected from its surrounding tissues endoscopically. With direct current energy via the HemoPro device, the side branches were coagulated and cut. The artery was transected at the wrist, then retrieved through a counterincision at the proximal forearm.

Results

There were no neurological or bleeding complications in the hand or forearm.

Conclusions

Endoscopic harvesting of the radial artery is feasible, faster, and produces a more aesthetically pleasing result than standard open harvesting. The learning curve associated with the endoscope can be overcome by practice on cadavers and by collaboration with a cardiac surgical team.

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Biportal thoracoscopic sympathectomy for palmar hyperhidrosis in adolescents

Clinical article

Scott D. Wait, Brendan D. Killory, Gregory P. Lekovic, and Curtis A. Dickman

Object

Palmar, axillary, and plantar hyperhidrosis is often socially, emotionally, and physically disabling for adolescents. The authors report surgical outcomes in all adolescents treated for palmar hyperhidrosis via bilateral thoracoscopic sympathectomy at the Barrow Neurological Institute by the senior author.

Methods

A prospectively maintained database of all adolescent patients undergoing bilateral thoracoscopic sympathectomy between 1998 and 2006 (inclusive) was reviewed. Additional follow-up was obtained as needed in clinic or by phone or written questionnaire.

Results

Fifty-four patients (40 females) undergoing bilateral procedures were identified. Their mean age was 15.4 years (range 10–17 years). Average follow-up was 42 weeks (range 0.2–143 weeks). Hyperhidrosis involved the palms alone in 10 patients; the palms and axilla in 6 patients; the palms and plantar surfaces in 17 patients; and the palms, axilla, and plantar surfaces in 21 patients. Palmar hyperhidrosis resolved completely in 98.1% of the patients. Resolution or improvement of symptoms was seen in 96.3% of patients with axillary and 71.1% of those with plantar hyperhidrosis. Hospital stay averaged 0.37 days with 68.5% of patients discharged the day of surgery. One patient experienced brief intraoperative asystole that resolved with medications and had no long-term sequelae. Otherwise, no serious intraoperative complications occurred. No patient required chest tube drainage. The percentage of patients who reported satisfaction and willingness to undergo the procedure again was 98.1%.

Conclusions

Biportal, bilateral thoracoscopic sympathectomy is an effective and low-morbidity treatment for severe palmar, axillary, and plantar hyperhidrosis.

Open access

Malignant progression of cerebellopontine angle solitary fibrous tumors following radiation: illustrative case

Anna K. La Dine, Nida Fatima, Zachary R. Barnard, William H. Slattery, and Gregory P. Lekovic

BACKGROUND

Intracranial solitary fibrous tumors (ISFTs) are rare mesenchymal tumors originating in the meninges and constitute a heterogeneous group of clinical and biological behavior. Benign histotypes, such as hemangiopericytomas are now considered as a cellular phenotypic variant of this heterogenous group of rare spindle-cell tumors. IFSTs are poorly recognized and remain a diagnostic challenge due to rarity and resemblance to other brain tumors. Previously, IFSTs were thought to pursue a slow, indolent, and nonaggressive course, however, a growing body of literature based on longer follow-up demonstrates an unpredictable clinical course and an uncertain diagnosis.

OBSERVATIONS

A rare case report of malignant transformation of IFST following radiation therapy is reported. In this case a 60-year-old female who underwent gross total resection of the cerebellopontine angle tumor with histopathology consistent with solitary fibrous tumor followed by salvage stereotactic radiosurgery, presented with another recurrence after 2 years of surgery. The authors performed complete removal of the tumor with pathology now consistent with malignant solitary fibrous tumor. A recent follow-up magnetic resonance imaging did not show any recurrence or residual tumor, and the patient reports a generalized well-being.

LESSONS

This report will help to understand the natural history and unusual clinical behavior of these intracranial tumors.