William E. Thorell

The long-term clinical outcome of patients undergoing anterior cervical discectomy with and without intervertebral bone graft placement

OBJECTIVE This retrospective study provides data on the long-term clinical outcomes of patients with either anterior cervical discectomy alone (ACD) or anterior cervical discectomy with intervertebral bone graft placement (ACDF). METHODS A questionnaire was mailed to 525 patients who had undergone ACD (290 patients) or ACDF (235 patients) at least 2 years previously. All procedures were performed by University of Nebraska Medical Center faculty in the Section of Neurosurgery. The follow-up period averaged 8.1 years, with a range of 2 to 14 years. RESULTS Two hundred sixty-two (49.9%) patients responded to the questionnaire. There was no demographic difference between respondents and nonrespondents (P > 0.05). Respondents who underwent ACDF reported fewer problems with pain than did those who underwent ACD (P < 0.05). A higher percentage of respondents with ACDF reported that they had normal function than did those who underwent ACD (P < 0.05). When limited to respondents who underwent first-time, single-level operations (191 patients), similar results were obtained for the pain parameter (P < 0.05) but not for the level of function (P = 0.25). Patients with longer follow-up periods had fewer problems with pain and better levels of function (P < 0.05). CONCLUSION Patients who underwent ACD or ACDF did well and benefited from their operations. Those who underwent ACDF did better than those who underwent ACD. Length of follow-up was also an important predictor of current levels of function and pain.

Patient outcome after resection of lumbar juxtafacet cysts

Study Design. Retrospective review of patients who underwent lumbar juxtafacet cyst resection with questionnaire follow-up. Objectives. Determine the long-term outcome after resection of lumbar juxtafacet cysts. Summary of Background Data. Juxtafacet cysts are uncommon causes of radicular pain and are often associated with significant spinal degenerative disease. Previous studies have not focused on the outcome of patients who have undergone resection. Methods. Charts of 29 patients who underwent lumbar juxtafacet resection were reviewed and an outcomes questionnaire was sent to each. Results. Thirty-three lumbar juxtafacet cysts were resected from 29 patients. Cysts, 31 (94%) from facets and 2 (6%) from the ligamentum flavum, most commonly arose at the L4–L5 level (51%). Twelve patients (41%) were found to have some degree of spondylolisthesis before surgery, while 26 patients (90%) had facet arthropathy. Two patients (7%) underwent concurrent resection and fusion. Recurrence occurred in 3%. Three patients (9%) had subsequent lumbar spine operations, including 2 fusions (6%). Incidental durotomy was the most common surgical complication occurring in 3 cases (9%). Twenty-four patients (83%) responded to follow-up questionnaire or phone interview. Mean length of follow-up was 24 months (4–64 months). Twenty patients (83%) reported improvement in pain, and 16 (67%) reported an improved level of function. All respondents reported some degree of improvement in their condition after surgery. Conclusions. Juxtafacet cysts are an uncommon cause of radiculopathy. Surgical resection is the treatment of choice with low rates of complications, recurrences, and residual complaints.

Angiogram-Negative Subarachnoid Hemorrhage: Outcomes Data and Review of the Literature

Spontaneous subarachnoid hemorrhage (SAH) is most commonly caused by rupture of a saccular aneurysm or other structural pathologies. Occasionally, no structural cause for the hemorrhage can be identified by radiographic imaging. These hemorrhages, termed angiogram-negative SAH, are generally considered to have a better prognosis than aneurysmal SAH. Angiogram-negative SAH subgroups include benign perimesencephalic SAH (PMH) and aneurysmal-type SAH. Outcome data for these subgroups differ from those for the group as a whole. We report data for 31 patients who presented to our institution from 2006 to the present. We performed a retrospective chart review, and report outcome data that include rates of rehemorrhage, hydrocephalus, vasospasm, permanent ischemic deficits, headaches, and outcomes based on modified Rankin Scale scores. We also performed a review of the literature and meta-analysis of the data therein. We compared rates of complications in the PMH subgroup and the diffuse-type hemorrhage subgroup. The chart review revealed no poor outcomes and no rehemorrhages in the patients with PMH. In the diffuse hemorrhage subgroup, 1 patient had a rehemorrhage and 2 patients had a poor outcome. Our literature review found an OR of 6.23 for a good outcome for PMH versus diffuse-type hemorrhage, and an OR of 2.78 for rehemorrhage in PMH versus diffuse-type hemorrhage. Angiogram-negative SAH is not a benign entity. Complications are present but are significantly reduced, and outcomes are improved, compared with aneurysmal SAH.

Type I spinal dural arteriovenous fistulas: historical review and illustrative case

Type I spinal dural arteriovenous fistulas are the most common vascular malformation of the spinal cord, and an important cause of reversible progressive myelopathy. This lesion remains underdiagnosed, with most patients presenting late in the course of the disease. In this article the authors provide a review of the literature with particular attention to historical aspects related to the pathophysiology, diagnosis, classification, clinical findings, natural history, and treatment of this lesion. An illustrative case is also provided.

Successful Endovascular Treatment of Pulsatile Tinnitus Caused by a Sigmoid Sinus Aneurysm: A Case Report and Review of the Literature

We describe the case of a 48-year-old woman who presented with a sigmoid sinus aneurysm. These rare entities have only recently been described in the literature and the ideal treatment approach has not been elucidated. This report represents additional evidence in a growing body of literature that suggests that endovascular therapy is a safe and effective therapeutic alternative to surgical reconstruction of the sigmoid sinus in selected cases of intractable pulsatile tinnitus.

Remote cerebellar hemorrhage following supratentorial cerebrovascular surgery

Three patients with remote cerebellar hemorrhage following supratentorial cerebrovascular surgery are presented. Remote cerebellar hemorrhage is a rare surgical complication that is most often associated with aneurysm clipping or temporal lobectomies. Bleeding occurs on the superior cerebellar cortex and is believed to be venous in origin. The precise pathogenesis of remote cerebellar hemorrhage has yet to be fully elucidated but is generally considered to be a consequence of intraoperative cerebrospinal fluid loss causing caudal displacement of the cerebellum with resultant stretching of the supracerebellar veins. This case series will hopefully shed further light on the incidence, presentation, workup, and treatment of this particular complication of supratentorial surgery.

Review of vertebral artery fenestration and novel extracranial fenestration

Although anomalies of the vasculature of the head and neck are ot particularly common, vertebral artery abnormalities have been ell described in the literature. Anatomical variations of the verebral arteries can pose significant risk for vascular injury during urgical and endovascular interventions [1]. Therefore it is imporant to understand and recognize these anomalies. The classic anatomic course of the vertebral artery has its oriin from the subclavian or innominate artery, enters the foramen ransversarium of C6–C2 where it courses around C1 to enter the oramen magnum and join the contralateral vertebral forming the asilar artery. There are some important variations of the usual natomy. The vertebral artery enters at the C6 foramen in 93% of atients; alternatively, the vertebral artery may enter at C4, C5, or 7 at the respective frequency of 1, 5, and 0.8% [1]. An aberrant verebral artery course may lead to iatrogenic injury during surgical pproaches to the cervical spine. Understandably, it has been proosed that the course of the vertebral artery should be noted in the nterpretation of all routine cervical spine MRIs. In addition to an berrant arterial route, various authors have previously described everal anomalous origins. The vessel itself may randomly divide nd reconstitute as seen in arterial fenestrations and duplications.

Hybrid peratrial double device closure of a patent foramen ovale and sinus venosus defect in an infant with vein of galen malformation

Vein of Galen aneurysmal malformation is the most common cerebral arteriovenous malformation in children. Neurointerventional embolization has improved outcomes with this lesion. An association with cardiac defects has been recognized and can increase the risk of systemic embolic events during treatment. Cardiopulmonary bypass (CPB) to correct the cardiac defect before repair of the malformation may be associated with compromised cerebral perfusion and possible neurologic injury. We describe a successful hybrid peratrial closure of two intracardiac shunts (a patent foramen ovale and a sinus venosus ASD) before neurointervention, avoiding CPB, and eliminating the intracardiac embolic risk during treatment of the vein of Galen malformation.

Long-term efficacy of continuous intrathecal opioid treatment for malignant and nonmalignant pain

Continuous intrathecal opioid administration via an implantable pump is an effective method of treatment for chronic pain. This retrospective study examines the long-term effectiveness of continuous intrathecal opioid treatment in patients with malignant and nonmalignant chronic pain syndromes. We reviewed charts from 81 patients with a history of permanent pump implantation between 1989 and 2000 for treatment of chronic pain due to malignant or nonmalignant causes. We conducted follow-up using telephone interviews. Of the 81 patients, 31 had placement of the pump for malignant pain and 50 had placement for nonmalignant pain. Of those with malignant pain, 30 were no longer living at the time of the study. We were unable to locate 21 of those with nonmalignant pain. Of the 30 patients who participated in the study, 24 patients continued to use the pump, and six patients had the pump removed. Follow-up ranged from 2.2 years to 7.3 years, with an average follow-up of 4.5 years. Patient age ranged from 42 years to 84 years with an average age of 64 years. Twenty-two of the 24 patients still using the pump considered it effective at relieving their pain, with an average pain relief of 62.92% ± 16.81%. Eighteen of the 24 patients required oral pain medications for breakthrough pain. All patients had had their intrathecal opioid dose increased since the original time of pump placement. Complications occurred in eight patients, including eight fractured catheters, two coiled catheters, one displaced catheter, three pump malfunctions, two displaced pumps, and two infections, one of which was meningitis. Nine pumps were replaced due to battery depletion. Eighteen of the 24 patients reported no side effects. Those reporting adverse effects named constipation, urinary retention, nausea, anorexia, light-headedness, fatigue, increased hunger, facial flushing, dry mouth, pruritus, and edema as their complaints. This study, along with previous studies of long-term continuous intrathecal opioid administration, demonstrate that it is an effective treatment modality for chronic pain of both malignant and nonmalignant origin.

Measuring Hemodynamic Changes in the Ophthalmic Artery During Applied Force for Noninvasive Intracranial Pressure Monitoring: Test Results in a Porcine Model

Possible traumatic brain injury victims would greatly benefit from a handheld, noninvasive intracranial pressure (ICP) monitoring tool, which a medic could operate in a remote area. Such a device would also benefit the transport of injured soldiers during en route medical care and critical care air transport. This study demonstrates the use of noninvasive blood flow measurements in the eye by ultrasound as a proxy for ICP. ICP was artificially raised in a porcine model and resultant blood flow change in the ophthalmic artery was measured. In addition, the ultrasound transducer itself was used to compress the eye further altering ophthalmic hemodynamics. Blood flow velocities at a range of applied forces and ICP were compared. It was found that 3.25 N of force applied to the cornea was sufficient to produce significant changes in ophthalmic artery blood dynamics regardless of the ICP value. Specifically, the change in resistivity index (RI) and pulsatility index (PI) as force was applied to the cornea correlated with ICP levels. In multiple animal experiments, the magnitude of PI/RI percent change was inversely related to differences in ICP. Force applied to the cornea at baseline ICP resulted in a 15% increase in PI/RI. Results indicate that as ICP increases, the percent change in PI/RI while force is applied decreases. The consistency of data collected indicates that a trend line developed with this data and from similar experiments could be used as a predictive measurement of ICP.