Search Results

You are looking at 1 - 10 of 33 items for :

  • Neurosurgical Focus x
  • By Author: Liu, James K. x
Clear All
Full access

James K. Liu

The surgical management of intramedullary spinal cord ependymomas remains a formidable challenge amongst neurosurgeons because of the potential risk of surgical morbidity. From on an oncological perspective, complete resection—if technically feasible—should be the goal of surgery, since this can result in excellent local control and progression-free survival. Advances in microsurgical techniques, intraoperative neurophysiological monitoring, and the use of lasers have contributed to our ability to achieve gross-total resection. This is also largely dependent on the presence of an identifiable surgical plane of dissection between the tumor and spinal cord, which appears to have a positive prognosis with overall neurological improvement. In this operative video manuscript, the author demonstrates an illustrative step-by-step technique for microsurgical resection of a thoracic intramedullary spinal cord ependymoma (T-3 to T-5) associated with an extensive cervicothoracic syrinx. The application of a handheld non-contact CO2 laser for performing the midline myelotomy is also highlighted. The operative technique and surgical nuances, including the surgical approach, intradural tumor removal, and closure, are illustrated in this video atlas.

The video can be found here: http://youtu.be/itE2tuBFmgw.

Free access

James K. Liu

Intraventricular meningiomas are rare tumors, accounting for approximately 0.5 to 3% of all intracranial meningiomas. The majority arise in the atrium of the lateral ventricle. The surgical management of these tumors remains a considerable challenge because of their deep location and proximity to critical structures. Complete resection, if safely possible, should be the goal of surgery since this results in the best rates of local control. Although various approaches exist to access the lateral ventricular system, selection of the optimal approach should be individualized to the patient based upon the location of the tumor within the ventricle, the tumor size, the origin of the vascular supply to the tumor, and the relationship to neighboring neurovascular structures at risk. In this operative video manuscript, the author demonstrates an illustrative step-by-step technique for microsurgical resection of a giant intraventricular meningioma of the left atrium via a transcortical parieto-occipital approach. The patient illustrated in this video presented with a large recurrent meningioma (> 5 cm) approximately 10 years after the initial resection. The tumor had grown around a pre-existing shunt catheter and resulted in loculated hydrocephalus. A complete resection and shunt revision were both performed at the same sitting. The operative technique and surgical nuances, including the surgical approach, intradural tumor removal, closure, and management of hydrocephalus are illustrated in this video atlas.

The video can be found here: http://youtu.be/vpdmZ1ccWSM.

Full access

Oren N. Gottfried, James K. Liu and William T. Couldwell

Object

The optimal management of glomus jugulare tumors remains controversial. Available treatments were once associated with poor outcomes and significant complication rates. Advances in skull base surgery and the delivery of radiation therapy by stereotactic radiosurgery have improved the results obtained using these treatment options. The authors summarize and compare the contemporary outcomes and complications for these therapies.

Methods

Papers published between 1994 and 2004 that detailed the use of radiosurgery or surgery to treat glomus jugulare tumors were reviewed. Eight radiosurgery series including 142 patients and seven surgical studies including 374 patients were evaluated for neurological outcome, change in tumor size (radiosurgery) or percent of total resection (surgery), recurrences, tumor control, need for further treatment, and complications.

The mean age at treatment for patients who underwent surgery and radiosurgery was 47.3 and 56.7 years, respectively. The mean follow-up duration was 49.2 and 39.4 months, respectively. The surgical control rate was 92.1%, with 88.2% of tumors totally resected in the initial surgery. A cerebrospinal fluid leak occurred in 8.3% of patients who underwent surgery and recurrences were found in 3.1%; the mortality rate was 1.3%. Among patients who underwent radiosurgery, tumors diminished in 36.5%, whereas 61.3% had no change in tumor size, and subjective or objective improvements occurred in 39%. Despite the presence of residual tumor in 100% of radiosurgically treated patients, recurrences were found in only 2.1%, the morbidity rate was 8.5%, and there were no deaths.

Conclusions

Death and recurrences after these treatments are infrequent, and therefore both treatments are considered to be safe and efficacious. Although surgery is associated with higher morbidity rates, it immediately and totally eliminates the tumor. The radiosurgery results are very promising, although the incidence of late recurrence (after 10–20 years) is unknown.

Full access

Christopher S. Eddleman and James K. Liu

resection of the tumor and involved optic nerve can be performed. If the globe is invaded by tumor and orbital proptosis is present, orbital exenteration should be considered. In patients with rapidly deteriorating vision, surgery for the goal of immediate optic decompression may be considered, especially if there is tumor within and around the optic canal with intracranial extension. This type of operation would include a frontotemporal craniotomy, posterior orbitotomy, anterior clinoidectomy, optic roof decompression, and opening of the falciform ligament and dura

Full access

James K. Liu and William T. Couldwell

Prolactin-secreting pituitary adenomas—prolactinomas—are the most common type of functional pituitary tumor. Treatment of hyperprolactinemia is indicated because of the consequences of infertility, gonadal dysfunction, and osteoporosis. Making the correct diagnosis is important because the first line of therapy is medical management with dopamine agonists. Medical therapy is effective in normalizing prolactin levels in more than 90% of patients, but long-term treatment may be required in some patients. Transsphenoidal surgery is usually indicated in those patients in whom medical therapy fails or cannot be tolerated, or in patients who harbor microprolactinomas. In experienced hands, a hormonal and oncological cure can be achieved in more than 90% of patients after transsphenoidal removal of microprolactinomas with minimal risks. Thus, surgery may be an option for microprolactinomas in a young patient who desires restoration of fertility and avoidance of long-term medical therapy. The authors review the diagnosis and management of prolactinomas, including medical therapy, surgical therapy, and stereotactic radiosurgery.

Full access

James K. Liu and William T. Couldwell

Cerebral revascularization is an important component in the surgical management of complex skull base tumors and aneurysms. Patients who harbor complex aneurysms that cannot be clipped directly and in whom parent vessel occlusion cannot be tolerated may require cerebrovascular bypass surgery. In cases in which skull base tumors encase the carotid artery (CA) and a resection is desired, a cerebrovascular bypass may be necessary in planned CA occlusion or sacrifice. In this review the authors discuss options for performing high-flow anterograde interposition CA bypass for lesions of the skull base. The authors review three important bypass techniques involving saphenous vein grafts: the cervical-to-petrous internal carotid artery (ICA), petrous-to-supraclinoid ICA, and cervical-to-supraclinoid ICA bypass. These revascularization techniques are important tools in the surgical treatment of complex aneurysms and tumors of the skull base and cavernous sinus.

Full access

James K. Liu and Jean Anderson Eloy

Anterior skull base (ASB) schwannomas are extremely rare and can often mimic other pathologies involving the ASB such as olfactory groove meningiomas, hemangiopericytomas, esthesioneuroblastomas, and other malignant ASB tumors. The mainstay of treatment for these lesions is gross-total resection. Traditionally, resection for tumors in this location is performed through a bifrontal transbasal approach that can involve some degree of brain retraction or manipulation for tumor exposure. With the recent advances in endoscopic skull base surgery, various ASB tumors can be resected successfully using an expanded endoscopic endonasal transcribriform approach through a “keyhole craniectomy” in the ventral skull base. This approach represents the most direct route to the anterior cranial base without any brain retraction. Tumor involving the paranasal sinuses, medial orbits, and cribriform plate can be readily resected. In this video atlas report, the authors demonstrate their step-by-step techniques for resection of an ASB olfactory schwannoma using a purely endoscopic endonasal transcribriform approach. They describe and illustrate the operative nuances and surgical pearls to safely and efficiently perform the approach, tumor resection, and multilayered reconstruction of the cranial base defect.

The video can be found here: http://youtu.be/NLtOGfKWC6U.

Full access

Smruti K. Patel, Qasim Husain, Jean Anderson Eloy, William T. Couldwell and James K. Liu

T he beginnings of transsphenoidal surgery date back over a century ago, when in 1907, Austrian neurosurgeon Dr. Hermann Schloffer carried out the first documented transnasal operation in a patient with a pituitary tumor. 42 , 48 , 49 This procedure was subsequently performed by surgeons in Vienna, von Eiselsberg and Hochenegg, in 1908. 42 , 52 A year later, in 1909, Theodor Kocher 35 , 42 modified the transnasal approach by introducing submucosal resection for better visualization, and within the year, various other modifications were introduced by

Full access

Richard F. Schmidt, Osamah J. Choudhry, Ramya Takkellapati, Jean Anderson Eloy, William T. Couldwell and James K. Liu

Until now, no such operation has yet been carried out on a living patient, at least none has been reported, obviously, because firstly the decision to perform such a difficult intervention bears the mark of a foolhardy novice, and is difficult even for the expert; secondly, because the function of the hypophysis remains obscure and hence the consequences of extirpation of the pituitary cannot be foreseen. H ermann S chloffer , 1906 40 These words were written by Hermann Schloffer 1 year before he performed the first successful transsphenoidal surgery

Full access

James K. Liu, Richard F. Schmidt, Osamah J. Choudhry, Pratik A. Shukla and Jean Anderson Eloy

E ndoscopic endonasal skull base surgery has benefited from significant advances over the past decade. In the EEA to the skull base, a minimal access technique is used via the transnasal route to expose and remove various midline ventral skull base lesions from the frontal sinus to the craniocervical junction. 15 Endoscopic endonasal approaches have many advantages over more traditional “open” transcranial approaches, including the absence of brain retraction and manipulation, better panoramic endoscopic visualization, and increased postoperative comfort