Faculty Bibliography

BACKGROUND: Peripheral nerve stimulation for chronic pain states is a safe and efficacious technique, being used with increasing frequency. The incidence of hardware-related complications requiring revision remains high. OBJECTIVES: The authors describe a technique of distal to proximal neurostimulator lead revision, which does not require the changing of generators or extension leads, and thus presumably will minimize further device-related complications. METHODS: The authors present a case series of 3 patients where the distal to proximal neurostimulator lead revision technique was utilized. RESULTS: The technique was well tolerated in each instance and all patients reported >50% pain reduction at long-term follow-up. CONCLUSIONS: The distal to proximal neurostimulator lead revision technique quickly and safely adjusts lead position, including both lead depth and lead tip location, without a need for replacement of components or revision of the entire system.

Giants have been a subject of fascination throughout history. Whereas descriptions of giants have existed in the lay literature for millennia, the first attempt at a medical description was published by Johannes Wier in 1567. However, it was Pierre Marie, in 1886, who established the term "acromegaly" for the first time and established a distinct clinical diagnosis with clear clinical descriptions in 2 patients with the characteristic presentation. Multiple autopsy findings revealed a consistent correlation between acromegaly and pituitary enlargement. In 1909, Harvey Cushing postulated a “hormone of growth" as the underlying pathophysiological trigger involved in pituitary hypersecretion in patients with acromegaly. This theory was supported by his observations of clinical remission in patients with acromegaly in whom he had performed hypophysectomy. In this paper, the authors present some of the early accounts of acromegaly and gigantism, and describe its historical evolution as a medical and surgical entity.

Distal ventriculo-peritoneal shunt migration and extra-peritoneal CSF pseudocyst formation are unusual complications of shunt placement. We present a 65-year-old-female who received a subgaleal-peritoneal shunt to decompress a post-surgical subgaleal fluid collection. Eight weeks later, shunt series showed tight coiling of the distal catheter, and operative exploration found the distal shunt tip to have migrated superficial to the rectus sheath, where it had become encapsulated in a pre-peritoneal CSF pseudocyst. Migration of the distal catheter into the abdominal wall was likely due to local inflammation of the inner surface of the abdomen, with pressure from intestinal peristaltic movements and intra-abdominal pressure, and continued inflammation at the distal catheter tip may have caused formation of a pre-peritoneal CSF pseudocystic dilatation. To date, this is the first reported case of distal shunt migration into the abdominal wall with subsequent formation of an extra-peritoneal pseudocyst and represents a rare event in the surgical management of peritoneal shunts.

The management of adult patients with Chiari malformation associated with syrinx remains controversial. Although an abundance of literature exists for the pediatric population, there is an absence of guidelines for the adult population. It is unclear which of the different surgical approaches is appropriate in patients with Chiari I malformations and syringomyelia. A 36-year-old female patient had a posterior fossa decompression 3years prior to recurrence. The patient developed recurrent symptoms with sensory loss and hyperesthesia in the right upper extremity. MRI revealed decreased cerebrospinal fluid flow at the craniocervical junction. The patient was taken to the operating room for revision of the posterior fossa decompression, lysis of adhesions and duraplasty. Re-exploration of a Chiari decompression, lysis of adhesions and revision duraplasty is an effective treatment option for recurrent syringomyelia

This report describes treatment of concurrent epidural and retropharyngeal abscesses and presents a novel surgical approach to treating this pathology. The treatment of epidural and retropharyngeal prevertebral abscesses requires surgical drainage in addition to systemic antibiotics. After the patient's airway is secured, urgent otolaryngologic surgery consultation is obtained for transoral drainage of the retropharyngeal abscesses to minimize risk to vascular and nervous structures within the neck. If epidural extension is also present, urgent neurosurgical evaluation and decompression may be necessary. We report a patient with an epidural and prevertebral abscess. A posterior approach was taken for wide decompression of the cervical spine and evacuation of the epidural collection. During this procedure, under fluoroscopic guidance, an 8 Fr soft rubber catheter was slowly advanced ventrally in the epidural space through the C5-6 intervertebral disk into the retropharyngeal abscess with evacuation of this collection as well. Using a single, wide posterior approach, the dorsal epidural, the ventral epidural, and prevertebral abscesses were all successfully evacuated. This report describes a novel approach for evacuation of prevertebral abscess concurrent with multilevel laminectomy for epidural abscess evacuation.

OBJECTIVE:Subarachnoid hemorrhage (SAH) has a worldwide incidence of approximately 10.5 cases per 100,000 person-years and constitutes 3% of all strokes. Erythropoietin (EPO) has recently been proposed for the treatment of a variety of brain diseases, including SAH, because of its neuroprotective effects. Hence, the current evidence in the published literature was reviewed to determine the potential utility of EPO in the treatment of SAH. METHODS:A careful retrospective review of the literature was performed to determine the potential benefit of employing EPO in the treatment of SAH and its sequelae. RESULTS:Careful literature review revelaed that the use of EPO may not necessarily reduce the incidence of vasospasm after SAH, but it may reduce the severity and its eventual outcome. CONCLUSION/CONCLUSIONS:Given the recent trial results, a dose-escalation study and subsequent randomized trial should be considered.

The intra-operative isocentric C-arm (Siremobil Iso-C 3D; Siemens Medical Solutions, Erlangen, Germany) allows for the acquisition and immediate interpretation of multiplanar three-dimensional images. The utility of isocentric fluoroscopy in surgery of the spine has been well described, in patients with percutaneous kyphoplasty, anterior cervical discectomy and fusion, fracture repair, as well as in percutaneous instrumentation at cervical, thoracic and lumbar levels. Two patients who underwent transoral odontoidectomy are presented in whom isocentric fluoroscopy was utilized to provide an intra-operative CT scan. Use of this technology allowed the surgeon to detect residual bone peri-operatively, thus allowing for a more extensive decompression and excellent clinical results. Intra-operative isocentric fluoroscopy in transoral odontoidectomy allows for peri-operative detection of residual bone fragments and intra-operative confirmation of complete decompression.

BACKGROUND:In the United States, TBI remains a major cause of morbidity and mortality in children and young adults. A total of 1.5 million Americans experience head trauma every year, and the yearly economic cost of this exceeds $56 billion. The magnitude of this problem has generated a great deal of interest in elucidating the complex molecular mechanism underlying cell death and dysfunction after TBI and in the development of neuroprotective agents that will reduce morbidity and mortality. METHODS:A review of recent literature on EPO, TBI, and apoptosis is conducted with analysis of pathophysiologic mechanisms of TBI. In addition, animal experiments and clinical trials pertaining to mechanisms of cell death in TBI and EPO as a neuroprotective agent are reviewed. CONCLUSION/CONCLUSIONS:The literature and evidence for EPO as a potent inhibitor of apoptosis and promising therapeutic agent in a variety of neurological insults, including trauma, are mounting. With the recent interest in clinical trials of EPO in human stroke, it is both timely and prudent to consider the use of this pharmaceutical avenue in TBI in man.

BACKGROUND:Pneumocephalus is commonly seen after neurosurgical procedures and is usually of little consequence. When an anatomical 1-way valve develops, there can be significant air entrapment, known as tension pneumocephalus. In cases of craniofacial resection, an iatrogenic ball-valve mechanism involving the nasopharynx can be created. CASE DESCRIPTION/METHODS:In this case of craniofacial resection, we find that a tension pneumocephalus developed after surgery, resulting in a change in the patient's mental status. A latissimus dorsi muscle flap, which had been created during surgery, was found to pulsate with the patient's respirations. This flap, along with the patient's nasopharynx, created a ball valve mechanism which led to entrapment and accumulation of intracranial air. This case demonstrates the use of endotracheal intubation as a means of bypassing a 1-way valve of this nature. CONCLUSION/CONCLUSIONS:Endotracheal intubation in conjunction with twist drill hole aspiration effectively resolves the pneumocephalus by both providing an outlet for trapped air and by removing the ball-valve mechanism from the circuit. Endotracheal intubation should be considered along with twist drill hole aspiration in the emergent management of tension pneumocephalus secondary to a nasopharyngeal ball-valve mechanism.

Malignant peripheral nerve sheath tumors (MPNSTs) are a rare variety of soft tissue sarcoma of ectomesenchymal origin. MPNSTs arise from major or minor peripheral nerve branches or sheaths of peripheral nerve fibers and are derived from Schwann cells or pluripotent cells of neural crest origin. Arthur Purdy Stout played a pivotal role in the development of our current understanding of the pathogenesis of peripheral nerve sheath tumors by identifying the Schwann cell as the major contributor to the formation of benign and malignant neoplasms of the nerve sheath. Although this fact remains essentially true, the cell of origin of the MPNST remains elusive and has not yet conclusively been identified. Some have suggested these tumors may have multiple cell line origins. In the present review, MPNSTs and their epidemiology, diagnosis, management, and treatment are discussed.