Donald W. Larsen

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

OBJECTIVETo assess the safety, feasibility, and clinical outcome of percutaneous transpedicular polymethylmethacrylate vertebroplasty (PTPV) for the treatment of spinal compression fractures causing refractory pain. METHODSWe 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. RESULTSA 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. CONCLUSIONPTPV 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.

Spinal dural arteriovenous fistulae: clinical features and long-term results.

OBJECTIVEThe goals of this study were to characterize the clinical, radiological, treatment, and outcome data associated with patients diagnosed with spinal dural arteriovenous fistulae (SDAVFs) at a single tertiary care institution over a 20-year period. METHODSA 20-year retrospective study was undertaken at our university hospital. Patients with mixed intracranial and spinal dural fistulas were excluded. A literature review of articles reporting endovascular or combined treatment of SDAVFs was performed. RESULTSBetween 1984 and 2005, our institution diagnosed and treated 63 patients (mean age, 62; 13 women, 50 men) with SDAVFs. The presenting symptoms were consistent with progressive myelopathy, and included lower extremity weakness (33 patients, 52%), parasthesias (19 patients, 30%), back pain (15 patients, 24%), and urinary symptoms (four patients, 6%). Thirty-nine patients underwent an initial endovascular embolization with 27 requiring only this first procedure for complete obliteration. On the other hand, 24 patients underwent an initial surgical procedure with 20 of them treated successfully with a single operation. Endovascular patients presented at mean age 62.3 years (standard deviation [SD], 10.6), were hospitalized for an average of 3.1 days (SD, 2.6), and were followed-up for 39 months (SD, 33). Surgical patients presented at mean age of 65.8 years (SD, 10.3), were hospitalized for 9.8 days (SD, 2.7), and were followed-up for 35 months (SD, 44). A significant improvement in Aminoff-Logue scores was found in both the endovascular and surgery groups (gait, P < 0.001; micturition, P = 0.005). The endovascular group had reduced hospitalization (P = 0.0001). No differences were found in the magnitude of clinical response to treatment. CONCLUSIONSDAVFs most commonly present with progressive myelopathy, yet often remain undiagnosed for months or years. Endovascular therapies and surgical therapies are associated with significantly improved symptoms once the definitive diagnosis of SDAVF is made.

Endovascular management of spinal dural arteriovenous fistulas. A review.

OBJECT Spinal dural arteriovenous fistulas (DAVFs) are the most common spinal vascular malformations and can be a significant cause of myelopathy, yet remain inefficiently diagnosed lesions. Over the last several decades, the treatment of spinal DAVFs has improved tremendously due to improvements in neuroimaging, microsurgical, and endovascular techniques. The aim of this paper was to review the existing literature regarding the clinical characteristics, classification, and endovascular management of spinal DAVFs. METHODS A search of the PubMed database from the National Library of Medicine and reference lists of all relevant articles was conducted to identify all studies pertaining to spinal DAVFs, spinal dural fistulas, and spinal vascular malformations, with particular attention to endovascular management and outcomes. RESULTS The ability to definitively treat spinal DAVFs using endovascular embolization has significantly improved over the last several decades. Overall rates of definitive embolization of spinal DAVFs have ranged between 25 and 100%, depending in part on the embolic agent used and the use of variable stiffness microcatheters. The majority of recent studies in which N-butyl cyanoacrylate or other liquid embolic agents were used have reported success rates of 70-90%. Surgical treatment remains the definitive option in cases of failed embolization, repeated recanalization, or lesions not amenable to embolization. Clinical outcomes have been comparable to surgical treatment when the fistula and draining vein remain persistently occluded. Improvements in gait and motor function are more likely following successful treatment, whereas micturition symptoms are less likely to improve. CONCLUSIONS Endovascular embolization is an increasingly effective therapy in the treatment of spinal DAVFs, and can be used as a definitive intervention in the majority of patients that undergo modern endovascular intervention. A multidisciplinary approach to the treatment of these lesions is required, as surgery is required for refractory cases or those not amenable to embolization. Newer embolic agents, such as Onyx, hold significant promise for future therapy, yet long-term follow-up studies are required.

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.

Microcatheter Embolization of Non-neurologic Traumatic Vascular Lesions

PURPOSE The authors report their experience over a 28-month period with embolization of 23 non-neurologic traumatic vascular lesions in 21 patients with use of a coaxial microcatheter coil delivery system. PATIENTS AND METHODS The injuries included pseudoaneurysms (n = 17), arteriovenous fistulas (n = 3), and sites of extravasation (n = 3) and were caused by gunshot, shotgun, and stab wounds, as well as motor vehicle accidents and iatrogenic trauma. All microcatheter embolizations except one were performed with 2.2-F Tracker-18 catheters inserted coaxially through 5.0-5.5-F guiding catheters. In one case, a coaxial 3-F Teflon catheter was used. In all cases platinum microcoils (almost all non-fibril) and/or straight platinum embolization wires (with fibrils) were used. RESULTS Twenty-one (91%) of 23 vascular lesions were successfully occluded with use of the microcatheter system. The two cases in which microcatheter embolization failed were successfully managed by using larger catheters and steel coils. Two patients with hepatic vascular lesions (one site of extravasation and a pseudoaneurysm) and one patient with a lower extremity arteriovenous fistula required two procedures each for successful treatment. Procedures were life-saving in at least two patients. Two lesions recurred during follow-up ranging from 3 days to 17 months. Both of these recurrences were successfully treated with transcatheter embolization, in one case with use of microcatheters. CONCLUSION Microcatheter embolization with platinum coils and wires is an effective means for treating traumatic vascular lesions. A coaxial microcatheter system allows for easier, more rapid coil/wire delivery to smaller, spasm-prone arteries in such cases.

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.

Covered stent-graft repair of the brachiocephalic arteries: technical note.

OBJECTIVE The use of a covered stent-graft to repair disruptions of the cervical carotid and vertebral arteries is described. This device maintains vessel patency while effectively excluding pseudoaneurysms, arteriovenous fistulae, and other breaches in the integrity of the arterial wall. METHODS Patient 1 bled from a large rent in the proximal common carotid artery as a result of tumor invasion. Patient 2 developed a vertebral arteriovenous fistula after a stab injury to the neck. Patient 3 developed cerebral infarction and an enlarging pseudoaneurysm of the internal carotid artery, also after a stab wound to the neck. RESULTS All three patients were treated with the Wallgraft endoprosthesis (Boston Scientific, Watertown, MA). In each case, the vessel wall defect was repaired while antegrade flow through the artery was preserved or restored. No neurological complications occurred as a result of stent-graft deployment. CONCLUSION Covered stent-grafts offer an alternative to endovascular occlusion of the parent vessel, thereby expanding the therapeutic options for patients with extracranial cerebrovascular disease. These three cases highlight the usefulness and versatility of these devices for endoluminal reconstruction of the brachiocephalic vasculature.

Traumatic vascular injuries and their management

Traumatic vascular injury to the intracranial and extracranial circulation can be sequelae of blunt, penetrating, or iatrogenic insults to the head, face, or neck. Treatment options include conservative medical management, or more invasive surgical or endovascular therapy. The appropriate treatment depends on the risk-benefit ratio of each option considering the natural history of each. Injuries include mild intimal irregularities, intimal flaps, pseudoaneurysms, fistulas, and occlusions. Need for treatment is partly determined by the collateral circulation to the brain, and the degree to which the lesion is thrombogenic. Advances in endovascular devices and techniques provide us with less invasive alternatives to surgery intervention or allow the interventionalist to treat lesions not treatable by any other modality.

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 Moscows 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.