Microcatheterization of the cervical epidural space via lumbar puncture: technical note.

OBJECTIVE: Deposition of opiates, corticosteroids, or local anesthetics into the epidural space is useful for the management of painful maladies of the cervical and thoracic spine. We describe a novel technique for epidural medication delivery via an angiographic microcatheter inserted at or below the conus and advanced cephalad under fluoroscopic guidance. Unlike commercial kits used by anesthesiologists, this method uses a radiopaque catheter that can be precisely targeted to the levels of interest. The hazards of direct puncture, such as "wet tap" or injury to the cervical cord, are minimized. METHODS: An 18-gauge Tuohy needle is inserted into the lumbar epidural space. A 2.3-French microcatheter and a 0.018-inch steerable guidewire are then introduced through the lumen of the needle. The catheter is fluoroscopically advanced to the cervical epidural space, where Depo-Medrol (Pharmacia & Upjohn, Kalamazoo, MI) is administered. As the catheter is withdrawn, additional corticosteroid can be delivered to the thoracic epidural space, together with long-acting morphine compounds or local anesthetics. Regional pressures within the epidural space and other physiological parameters can be measured, and the local microenvironment can be sampled. RESULTS: To date, we have performed 16 procedures for 13 patients. All patients reported improvement, of varying extent and duration. There have been no complications. CONCLUSION: Our system of accessing the epidural space has many advantages, compared with direct puncture and commercially available kits. It provides a safe means of delivering epidural medication to multiple spinal levels and permits measurement of physiological variables that may be useful in the diagnosis and treatment of cervical and thoracic spine disease.

Percutaneous transpedicular polymethylmethacrylate vertebroplasty for the treatment of spinal compression fractures.

OBJECTIVE: To assess the safety, feasibility, and clinical outcome of percutaneous transpedicular polymethylmethacrylate vertebroplasty (PTPV) for the treatment of spinal compression fractures causing refractory pain. METHODS: We retrospectively reviewed a consecutive group of patients undergoing PTPV at our institution between April 1998 and January 2001. Outcome measures included analgesic requirements, ambulatory status, sleep comfort, and overall quality of life 2 weeks after the procedure. RESULTS: A total of 97 patients (73 women and 24 men) underwent 258 PTPV procedures during 133 treatment sessions. The mean age was 76 years (range, 42-99 yr). The mean duration of follow-up was 14.7 months (range, 2-35 mo). Most of the patients had osteoporotic compression fractures, although some had osteolytic malignancies. Complete follow-up was obtained in 81 patients (84%). Narcotic and analgesic usage decreased in 63% of patients, increased in 7%, and remained the same in 30%. Ambulation and mobility were improved in 51%, worse in 1% and the same in 48%. One-half of the patients were able to sleep more comfortably after the procedure, whereas the other half remained the same. Most patients who reported no change in sleep or ambulation had experienced no impairment of these activities before PTPV. Overall, 74% of patients believed that PTPV significantly enhanced their quality of life and 26% reported no change. No patient was worse after PTPV. One patient with preexisting pneumonia died of respiratory failure after the procedure; another died of an acute stroke weeks later. One patient developed symptomatic pulmonary embolism of cement, and another developed transient quadriceps weakness from radiculopathy. Other complications were minor and infrequent. There were no infections. CONCLUSION: PTPV provided significant relief in a high percentage of patients with refractory pain. PTPV is a safe and feasible treatment for patients with spinal compression fractures.

Percutaneous carotid angioplasty and stenting with the use of gadolinium in lieu of iodinated contrast medium: technical case report and review of the literature.

OBJECTIVE AND IMPORTANCE: We describe a patient who underwent percutaneous transluminal carotid angioplasty and stent placement with the use of intra-arterial gadolinium (Gd-DTPA) instead of iodinated contrast medium. This represents one of the first published reports of the use of Gd-DTPA as an angiographic contrast agent for an interventional neuroradiological procedure. CLINICAL PRESENTATION: A 75-year-old man with renal insufficiency and multiple comorbidities developed amaurosis fugax. Doppler examination revealed high-grade stenosis of the right internal carotid artery. INTERVENTION: The patient underwent percutaneous transluminal balloon angioplasty with endovascular stent placement for 95% narrowing of the proximal right internal carotid artery. Because of his impaired renal function, the procedure was performed with the use of Gd-DTPA as the sole contrast agent. Approximately 60 ml of contrast medium (twice the volume typically used for a magnetic resonance imaging study) was used. There were no neurological, renal, or other complications. CONCLUSION: Intra-arterially administered Gd-DTPA may be substituted for iodinated contrast agents in complex neuroendovascular procedures. This capacity expands the armamentarium for interventional neuroradiological procedures.

Balloon-protected carotid angioplasty.

OBJECTIVE: We describe a method of protecting the distal cerebral circulation during carotid angioplasty and report results using the technique in 17 procedures. METHODS: Eleven men and five women with carotid stenoses ranging in severity from 70 to 95% underwent the procedure. The technique was used bilaterally in one patient. A compliant silicone balloon was used to occlude the distal internal carotid artery during the angioplasty phase, when the largest number of emboli are generated. After angioplasty, debris was then flushed into the external circulation while the occlusion balloon remained inflated. The subsequent passage of an exchange guidewire through the angioplasty catheter, with the occlusion balloon deflated, allowed continuous guidewire access across the area of stenosis and facilitated the subsequent placement of a stent. RESULTS: The technique was successful in 16 (94%) of 17 procedures. In the one patient in whom the occlusion balloon could not be advanced across the stenosis, the patient experienced a transient ischemic attack after subsequent angioplasty that was performed without protection. Otherwise, no complications occurred among the 15 patients undergoing successful, balloon-protected angioplasty. Inflation times for the occlusion balloon did not exceed 5 minutes in any patient. CONCLUSION: This method of cerebral protection prevents the intracranial embolization of thrombus and atherosclerotic debris, while allowing continuous guidewire access across the site of stenosis. The success of this technique and a similar method used by Theron et al. supports the use of balloon protection as a means of reducing the risk of stroke associated with carotid angioplasty.

Parent vessel Guglielmi detachable coil herniation during wide-necked aneurysm embolization: treatment with intracranial stent placement: two technical case reports.

OBJECTIVE AND IMPORTANCE: Despite recent advances in technology, parent vessel coil herniation occasionally complicates successful Guglielmi detachable coil embolization, particularly in wide-necked aneurysms. We report endovascular stent deployment performed in two patients specifically to treat this complication. CLINICAL PRESENTATION: Two patients underwent Guglielmi detachable coil embolization of cavernous segment aneurysms. Both developed coil herniation into the internal carotid artery. In one patient, the herniation occurred during the initial procedure; in the other, it was discovered in a delayed fashion during a follow-up examination for ocular symptoms. INTERVENTION: In both patients, endovascular stent deployment was performed to isolate the herniated portion of the coil from the internal carotid lumen. Follow-up angiography at 6 months demonstrated no aneurysm recanalization and no stenosis of the parent internal carotid artery in the stented region in either patient. CONCLUSION: The use of intraluminal stents has been reported to be a helpful technical adjunct to the conventional endovascular treatment of aneurysms and balloon angioplasty. One additional indication for the use of this technology is sequestering herniated coils from the lumen of the parent artery to reduce potential embolic or occlusive sequelae.

A tribute to Dr. Fedor A. Serbinenko, founder of endovascular neurosurgery.

From humble beginnings in the former Soviet Union, Fedor A. Serbinenko, M.D., Ph.D., became a leading figure at Moscow's famed Burdenko Neurosurgery Institute. While there, he invented and perfected the technique of balloon embolization, which was destined to change the practice of neurovascular surgery forever. We present the life and achievements of the father of endovascular neurosurgery.

Causes and management of aneurysmal hemorrhage occurring during embolization with Guglielmi detachable coils.

OBJECT: The purpose of this review is to describe the incidence, causes, management, and outcome of aneurysmal hemorrhage that occurred in patients during endovascular treatment with the Guglielmi detachable coil (GDC) system. METHODS: At the authors' institution between September 1991 and August 1995, more than 200 patients were treated using GDCs for intracranial aneurysms. The first 200 patients treated in this fashion were reviewed and all who experienced new subarachnoid hemorrhage (SAH) during the procedure were identified. Angiographic studies were also reviewed and patients were contacted for longer-term follow up when possible. Four patients who experienced intraprocedural SAH were identified. The causes of hemorrhage were believed to be perforation of the aneurysm by the guidewire in one patient, perforation by the microcatheter in a second, and perforation by the delivery wire in a third. The fourth patient had a hemorrhage during injection of contrast material for control angiographic studies after placement of the final coil. One patient died, but the other three experienced no neurological symptoms or recovered without acquiring additional deficits. Overall a procedural hemorrhage rate of 2% was seen, with permanent morbidity and mortality rates of 0% and 0.5%, respectively. CONCLUSIONS: Although SAH during endovascular treatment of intracranial aneurysms remains a significant risk, its incidence is low and a majority of patients can survive without serious sequelae.

Carotid endarterectomy compared with angioplasty and stenting: the status of the debate.

Endarterectomy is the treatment of choice for patients with symptomatic stenosis of the internal carotid artery. Recently, debate has arisen over the potential benefits of endovascular techniques. Although retrospective analyses of angioplasty and stenting procedures suggest comparable clinical efficacy to endarterectomy, prospective evaluation is pending. The authors review the status of the debate and discuss those issues on both sides that are particularly contentious and clinically relevant.

Dural arteriovenous fistulas of the marginal sinus.

PURPOSE: To investigate the clinical presentation, angiographic findings, endovascular management and clinical outcome in dural arteriovenous fistulas (DAVFs) of the marginal sinus. METHODS: Fourteen patients with DAVFs of the marginal sinus were identified from angiographic studies and medical records of all patients treated for DAVFs at our institution between July 1990 and August 1995. The endovascular treatment and clinical outcomes of these patients are reported. RESULTS: Eleven patients had pulse-synchronous bruit, two had intracranial hemorrhage, and one had ataxia. Thirteen patients were cured with endovascular techniques alone and one was cured by a combination of preoperative embolization followed by surgical obliteration of the fistula. The sole complication of treatment was a partial left hypoglossal nerve palsy, which resolved spontaneously. CONCLUSION: DAVFs of the marginal sinuses are potentially life-threatening lesions that can be treated with endovascular techniques for a high rate of cure and a low rate of morbidity.

Cerebrospinal fluid flow artifact. A possible pitfall on fast-spin-echo MR imaging of the spine simulating intradural pathology.

We have noted that fast-spin-echo T2-weighted images of the cervical and thoracic regions of the spine can produce low-signal artifacts in the spinal subarachnoid space which might be misinterpreted as tumor or abnormal vascular flow voids. These are possibly related to complex cerebrospinal fluid pulsatile flow and should be recognized as artifactual by the radiologist.

Endovascular treatment of basilar tip aneurysms using electrolytically detachable coils.

Preliminary experience using electrolytically detachable coils to treat basilar tip aneurysms in 33 patients is described. The most frequent presentation was subarachnoid hemorrhage (SAH) in 23 patients. All patients were referred after neurosurgical assessment and exclusion as candidates for surgical clipping of their aneurysms. At the time of initial treatment complete aneurysm occlusion was achieved in seven (21.2%) of 33 patients. In 17 of the patients (51.5%), greater than 90% but less than 100% aneurysm occlusion was achieved. Angiographic follow up (mean 11.7 months) was available in 19 patients. At follow- up angiography four (21%) of 19 aneurysms were 100% occluded and 12 (63.2%) of 19 were more than 90% but less than 100% occluded. The mean clinical follow-up time in treated patients surviving beyond the initial treatment period is 15 months. One patient suffered major permanent morbidity from thrombosis of the basilar tip region a few hours after coil placement. One patient treated following SAH experienced further hemorrhage 6 months later. No other patient suffered direct or indirect permanent morbidity as a consequence of this method of treatment. The authors believe that this technique is a reasonable alternative for patients who are not candidates for conventional surgical treatment or in whom such treatment has failed. This study's follow-up period is brief and greater experience with long-term follow-up study is mandatory.

Treatment of massive posterior epistaxis by detachable coil embolization of a cavernous internal carotid artery aneurysm.

We present a case of massive posterior epistaxis caused by a cavernous internal carotid artery aneurysm. This lesion was treated with endovascular placement of electrolytically detachable platinum embolization coils. The treatment resulted in cessation of epistaxis until the patient's death 3 months following embolization. We discuss aspects of using these above coils for this condition.

Endovascular management of biopsy-related posterior inferior cerebellar artery pseudoaneurysm.

We present a case of a posterior inferior cerebellar artery pseudoaneurysm with subarachnoid hemorrhage resulting from a transoral head and neck tumor biopsy. The pseudoaneurysm was managed using transcatheter coil embolization.

Spinal dural arteriovenous fistulas supplied by branches of the internal iliac arteries.

Spinal dural arteriovenous fistulas are abnormal arteriovenous connections on the surface of the dura. They are supplied by branches of intercostal, lumbar, vertebral, middle sacral, or subclavian arteries and rarely by branches of the internal iliac arteries. We present four cases of spinal dural arteriovenous fistulas supplied exclusively by branches of the internal iliac artery in which the clinical and magnetic resonance presentation were not suggestive of this unusual supply. In our experience, internal iliac artery supply was observed in 12.5% of cases of spinal dural arteriovenous fistulas. We recommend that selective internal iliac arteriography be included in the angiographic evaluation of patients suspected of having a spinal dural arteriovenous fistula.

Angiographic embolization of renal stab wounds.

Nonoperative management of renal stab wounds following complete radiographic assessment has become an accepted if not preferred therapeutic option. Selected injuries, however, including renal artery branch injuries, often require surgical intervention and result in partial or total nephrectomy. We report our experience with 16 renal branch arterial injuries secondary to street stabbing during the last 10 years that were managed with angiography and embolization techniques. Angiography with embolization was the initial treatment in 11 patients, while 5 had undergone emergency surgical intervention initially because of hemodynamic instability. Subsequently, gross hematuria recurred in the latter 5 patients and they were managed angiographically. Overall, 14 of 16 patients had prompt hemostasis documented either on the post-embolization angiogram or by clinical assessment. In 2 patients bleeding was increased but partial nephrectomy ultimately was required. Complications included nontarget embolization in 2 patients: 1 subsequently had hypertension and 1 had no untoward effect as a result of this complication. We conclude that angiography with transcatheter embolization techniques provides a safe and effective means of managing renal artery branch injuries secondary to stab wounds.

Quantity of protein deposited on hydrogel contact lenses and its relation to visible protein deposits.

The purposes of this study were to determine if the quantity of protein deposited (QPD) upon hydrogel lenses was affected by enzymatic cleaning and to test the potential relation between QPD and visible protein deposition (VPD) and change. Seventy-four contact lens patients classified as "heavy depositors" wore new lenses for an average of 80 (SD = 32) days. Cleaning and disinfection solutions varied. One lens was cleaned weekly by a papain enzymatic treatment. The distribution of QPD measurements was bimodal and was related to the FDA material for nonionic, low water content lenses (FDA Materials Group no. 1). The mean deposition was 45 micrograms/cm2 (N = 112) compared with that of ionic, high water content lenses (FDA Materials Group no. 4), which was 1010 micrograms/cm2 (N = 30). VPD distributions were the same for the FDA Group no. 1 and no. 4 lenses. Enzymatic treatment did not significantly reduce QPD; however, enzymatic treatment did reduce VPD. Thus QPD and VPD are independent phenomena and possible reasons for this are given.

Proton NMR relaxation in hydrogel contact lenses: correlation with in vivo lens dehydration data.

A study of hydrogel contact lenses was undertaken to determine whether NMR relaxation data can be used as a predictor for on-eye lens dehydration. Proton NMR relaxation times (T1 and T2), were determined for a series of contact lenses for which on-eye dehydration data were also available. NMR relaxation times were found to depend upon lens water content, but the dependence was not monotonic. T1 values varied between 100 and 800 msec, and T2 values varied between 6 and 85 msec for the lenses studied. In this study, the NMR signal and corresponding relaxation times are average values, derived both from lens water protons as well as from exchangeable polymer protons. A simple analysis of the data indicates that the mobility of these protons varies by more than a factor of 10 for the lenses studied. A test for linear correlation between NMR relaxation rate, 1/T1 and relative change in lens water mass, % delta mw gave r = -0.830 for all data, and r = 0.904 if one lens was excluded.