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G R Duckwiler

Publications and source records attributed to G R Duckwiler.

At least 19 recordsLinked to original sources
PubMed2001

N-butyl 2-cyanoacrylate embolization of spinal dural arteriovenous fistulae.

BACKGROUND AND PURPOSE: Because they are not well established, we investigated the technical success and recurrence rates of n-butyl 2-cyanoacrylate (NBCA) embolization of spinal dural arteriovenous fistulae (SDAVF), and assessed clinical outcomes. METHODS: We retrospectively studied all patients with SDAVF treated by NBCA embolization at our institution over an 8-year period. Gait and micturition disabilities were analyzed. Follow-up periods averaged 3.1 years (range, 1 month to 8.9 years). RESULTS: NBCA embolization was feasible in 74% (20/27) of patients. Of 20 patients who underwent embolization, initial embolization failure occurred in two (10%) and fistula occurrence in three (15%). All five patients in whom NBCA embolization failed underwent surgery. All patients who underwent embolization had either improved (55%) or unchanged (45%) gait disability at last follow-up. Seventeen (85%) patients had improved (40%) or unchanged (45%) micturition disability, but three (15%) had worsened. Mean Aminoff gait disability grade significantly decreased at last follow-up (2.4 [1.4] average [SD] vs 3.2 [1.4] [P = .0008]). Mean micturition disability grade decreased, but not significantly (1.4 [1.0] vs 1.7 [1.1] [P = .28]). CONCLUSION: NBCA embolization of SDAVF was technically feasible in 75% of patients. Initial apparent successful embolization was achieved in 90%; the fistula recurrence rate (failure to occlude the draining vein) for NBCA was 15%. Comparing favorably to surgical series, NBCA embolization of SDAVF appears efficacious, significantly improving mean gait disability by almost one grade at last follow-up. Close clinical and angiographic surveillance is mandatory. Longer and more uniform follow-up is needed to determine if clinical improvement and stabilization after NBCA embolization are sustained.

Aged↗
PubMed2000

Pulmonary emboli following therapeutic embolization of cerebral arteriovenous malformations in children.

BACKGROUND: Reports of the complicating side effect of pulmonary embolism (PE) following endovascular therapy of cerebral arteriovenous malformations (AVM) in children have been limited in number. Details of its occurrence are yet to be fully elucidated. OBJECTIVE: The hypothesis is that inadvertent pulmonary migration of embolic material is common and may go unrecognized. MATERIALS AND METHODS: Forty-seven patients (ages 1 day to 16 years and 11 months) underwent embolization of a cerebral AVM with at least one material (cyanoacrylate, platinum coils, detachable balloons, polyvinyl alcohol particles). The medical records and chest radiographs were reviewed retrospectively. Chest radiographs were available in 34 patients. The radiographs were analyzed for the presence or absence of foreign material in the lungs. RESULTS: The chest radiographs in 12 patients (35%) showed pulmonary deposits of embolic material; cyanoacrylate in 10 patients and platinum coils in 2. Two of the patients with cyanoacrylate deposits in the lungs developed respiratory distress that required endotracheal intubation. The patients gradually improved after a time period of 7-10 days with conservative treatment. CONCLUSION: PE is not an uncommon complication in children undergoing embolization of brain AVM. Although usually asymptomatic, PE may cause severe symptoms.

Adolescent↗
PubMed2000

X-ray videodensitometric methods for blood flow and velocity measurement: a critical review of literature.

Blood flow rate and velocity are important parameters for the study of vascular systems, and for the diagnosis, monitoring and evaluation of treatment of cerebro- and cardiovascular disease. For rapid imaging of cerebral and cardiac blood vessels, digital x-ray subtraction angiography has numerous advantages over other modalities. Roentgen-videodensitometric techniques measure blood flow and velocity from changes of contrast material density in x-ray angiograms. Many roentgen-videodensitometric flow measurement methods can also be applied to CT, MR and rotational angiography images. Hence, roentgen-videodensitometric blood flow and velocity measurement from digital x-ray angiograms represents an important research topic. This work contains a critical review and bibliography surveying current and old developments in the field. We present an extensive survey of English-language publications on the subject and a classification of published algorithms. We also present descriptions and critical reviews of these algorithms. The algorithms are reviewed with requirements imposed by neuro- and cardiovascular clinical environments in mind.

Algorithms↗
PubMed2000

Natural history of the neck remnant of a cerebral aneurysm treated with the Guglielmi detachable coil system.

OBJECT: The long-term durability of Guglielmi detachable coil (GDC) embolization of cerebral aneurysms is still unknown. The purpose of this study was to evaluate the anatomical evolution of neck remnants in aneurysms treated with GDCs. METHODS: Of 455 aneurysms treated with GDCs from 1990 to 1998 at the University of California at Los Angeles Medical Center, 178 aneurysms (39%) had residual necks postembolization. Long-term follow-up angiograms were obtained in 73 of these aneurysms in 71 patients. The mean duration of angiographic follow up was 17.3 months. Twenty-four of the aneurysms were small with small necks, 24 were small with wide necks, 15 were large, and 10 were giant aneurysms. In small aneurysms with small necks, postembolization angiography revealed 12 aneurysms (50%) with progressive thrombosis, eight (33%) unchanged, and four (17%) with recanalization. In small aneurysms with wide necks, six (25%) had progressive thrombosis, eight (33%) remained unchanged, and 10 (42%) had recanalization. In large aneurysms, two (13%) were unchanged and 13 (87%) had recanalization. Of the giant aneurysms only one (10%) remained unchanged and nine (90%) had recanalization. Overall, 18 aneurysms (25%) exhibited progressive thrombosis, 19 (26%) remained unchanged, and 36 (49%) displayed recanalization on follow-up angiography. During the last 2 years of the study, the recanalization rate decreased and a higher rate of progressive thrombosis was noted in aneurysms with small necks. These positive changes are related to important new technical developments. CONCLUSIONS: Treatment with GDCs appears to be effective and the results permanent in most small aneurysms with small necks. However, there are important technical limitations in the current GDC technology that prevent recanalization in wide-necked or large or giant aneurysms.

Adult↗
PubMed2000

Endovascular treatment of basilar tip aneurysms using Guglielmi detachable coils: anatomic and clinical outcomes in 73 patients from a single institution.

OBJECTIVE: Seventy-three consecutive patients with 75 basilar tip aneurysms were treated with Guglielmi detachable coil (GDC) technology. Their anatomic and clinical outcomes are discussed. METHODS: Seventy-five basilar tip aneurysms were treated with the GDC system at the University of California, Los Angeles Medical Center from 1990 to 1999. The average age of the population was 48.3 years (range, 28-82 yr). Forty-two patients (57.5%) presented with acute subarachnoid hemorrhage, 8 patients (10.9%) had unruptured aneurysms with mass effect, and 23 patients (31.5%) had incidental aneurysms. Thirty-one aneurysms (41.3%) were small with a small neck, 18 (24%) were small with a wide neck, 16 (21.3%) were large, and 10 (13.3%) were giant aneurysms. RESULTS: Immediate anatomic outcomes demonstrated complete or near-complete occlusion in 64 aneurysms (85.3%) and incomplete occlusion in 7 aneurysms (9.3%). Four aneurysms (5.3%) could not be embolized because of anatomic difficulties. Of the 69 patients treated with GDCs, 63 patients (91.3%) remained neurologically intact or unchanged from their initial clinical status. Procedure-related morbidity and mortality were 4.1% and 1.4%, respectively. Long-term follow-up angiograms were obtained in 41 patients with 42 aneurysms. Thirty aneurysms (71.4%) demonstrated complete or near-complete occlusion. One incompletely embolized giant aneurysm ruptured during the follow-up period. CONCLUSION: In contrast to surgical clipping of basilar tip aneurysms, the main technical challenge of the Guglielmi detachable coiling procedure depends on the shape of the aneurysm, not its location. The results of this study indicate that endovascular GDC technology is an appropriate therapeutic alternative in ruptured or unruptured basilar tip aneurysms regardless of patient age, clinical presentation, clinical status, or timing of treatment.

Adult↗
PubMed1999

Balloon-assisted Guglielmi detachable coiling of wide-necked aneurysms: Part I--experimental evaluation.

OBJECTIVE: Balloon-assisted technique is a promising technical adjunct to use of Guglielmi detachable coils for embolization of wide-necked aneurysms. In this study using experimental aneurysms in swine, the safety and long-term efficacy of this technique were evaluated. METHODS: Sixteen wide-necked aneurysms (sidewall model) were surgically created in common carotid arteries of swine. In the acute study of eight aneurysms, intra-aneurysmal pressure changes were recorded during balloon inflation in different positions of the balloon relative to the neck of the aneurysm. In the chronic study, eight aneurysms were treated with this technique, and follow-up angiography was performed 14 days postembolization. The animals were then killed for macroscopic evaluation. RESULTS: In the acute study, the systolic intra-aneurysmal blood pressure increased with balloon inflation at the distal portion of the neck and with balloon inflation/occlusion across the entire neck of the aneurysm. In the chronic study, seven of eight cases were embolized with satisfactory occlusion, and six showed no coil displacement on the follow-up angiogram. In five cases, macroscopic evaluation of the aneurysm showed that the coils were compacted at the neck of the aneurysm with a concave shape consistent with the shape of the inflated balloon across its neck. CONCLUSION: This preliminary study indicates that balloon-assisted Guglielmi detachable coiling technology may produce a temporary increase of pressure within the aneurysm while occluding the aneurysmal neck during coil delivery. This sudden change of intra-aneurysmal pressure may potentially be the cause-of aneurysm rupture in the clinical setting. The balloon must be inflated and deflated very slowly to minimize these potentially risky hemodynamic changes. Although angiographic follow-up showed successful obliteration of aneurysms, further long-term angiographic studies are necessary to establish the durability of this technique.

Animals↗
PubMed1999

Ballonn-assisted Guglielmi detachable coiling of wide-necked aneurysma: Part II--clinical results.

OBJECTIVE: To demonstrate the indications and efficacy of balloon-assisted Guglielmi detachable coiling (BAGDC). METHODS: BAGDC was used for 23 patients (19 women and 4 men; mean age, 55 yr) (17%) of a series of 136 consecutive patients who underwent Guglielmi detachable coiling of aneurysms. Every aneurysm had a wide neck, and 57% were large (11-25 mm in diameter). In each case, a nondetachable silicone balloon was advanced in the parent artery and inflated to occlude the neck of the aneurysm and stabilize the Guglielmi detachable coil delivery microcatheter at the aneurysm neck. Guglielmi detachable coils were then deposited. The balloon was then deflated to verify appropriate coil placement and stability, and finally, the Guglielmi detachable coils were detached. This process was repeated until the aneurysm was suitably embolized. RESULTS: One hundred percent aneurysm embolization was achieved in 19 patients (83%), and 95 to 100% embolization was achieved in 4 patients (17%). Twenty-two patients (96%) were at their preprocedure neurological baseline after the procedure. There were three complications in the study. One patient died after sustaining subarachnoid hemorrhage-induced vasospasm followed by a hemorrhagic infarction. She had undergone an unsuccessful clip ligation of her aneurysm. A second patient developed an intra-arterial thrombus at the site of balloon deployment. She sustained ischemic events that were treated with thrombolysis and anticoagulation. She made a complete recovery. A third patient developed an intra-arterial thrombus that was noted during the procedure. She was treated with intra-arterial thrombolysis and experienced no clinical sequelae. No permanent complications could be attributed to the BAGDC technique. The median clinical follow-up time was 10 months. No patient required additional treatment or developed a recurrent aneurysm neck or lumen. CONCLUSION: BAGDC is a promising adjunct to the treatment of wide-necked aneurysms. The balloon serves two purposes: it stabilizes the microcatheter in the aneurysm during coil delivery, and it forces the coil to assume the three-dimensional shape of the aneurysm without impinging on the parent artery.

Adult↗
PubMed1999

Comparison of methods for instantaneous angiographic blood flow measurement.

Several different algorithms have been reported for measurement of blood flow rates and velocities from digital x-ray angiograms. We compare four videodensitometric methods: (1) distance-density curve matching (DDCM), (2) distance-density curve matching with curve-fitting (DDCM-F), (3) bolus mass tracking with curve-fitting (BMT-F) and (4) fluid continuity method (FCM). We tested the flow algorithms with simulated angiograms and with images obtained from a programmable flow phantom under clinically realistic flow and contrast injection conditions including imperfect mixing. All methods perform well for simulated angiograms. On phantom angiograms with constant flow, all methods tended to underestimate flow velocities by at least 7% and demonstrate high variability between consecutive measurements. The FCM demonstrated relatively low variability, but a large negative bias. The DDCM method was moderately biased and had the highest variability. The BMT-F method demonstrated the lowest bias (-7.1%) and the lowest variability both within (27%) and between (27%) studies. No method yields reliable measurements near the peak contrast opacification, when little or no gradient of contrast is present. The extrapolating version of the BMT-F method was also the most robust for estimation of interframe displacements longer than the field of view.

Algorithms↗
PubMed1999

Embolization of incidental cerebral aneurysms by using the Guglielmi detachable coil system.

OBJECT: Guglielmi detachable coil (GDC) technology is a valuable therapeutic alternative to the surgical treatment of ruptured or incidental intracranial aneurysms. The authors describe their technical and clinical experience in the use of the GDC technique in patients who underwent endovascular occlusion for the treatment of incidentally found intracranial aneurysms. METHODS: One hundred fifteen patients with 120 incidentally found intracranial aneurysms underwent embolization by means of the GDC endovascular technique. Ninety-one patients were females and 24 were males. Patient age ranged from 13 to 80 years. In 64 patients the incidental aneurysms were discovered when unrelated nonneurological conditions signaled the need for angiography or magnetic resonance angiography (Group 1). Twenty patients who presented with incidental aneurysms that were discovered during treatment for an acutely ruptured aneurysm underwent treatment of both types of aneurysm during the acute phase of subarachnoid hemorrhage (SAH) (Group 2). Sixteen patients with incidental aneurysms were treated during the chronic phase of SAH (Group 3). Group 4 included 15 patients who had incidental aneurysms associated with brain tumors or arteriovenous malformations. Angiographic results revealed complete or near-complete occlusion in 109 aneurysms (91%) and incomplete occlusion in five aneurysms (4%). Guglielmi detachable coil embolization was attempted unsuccessfully in six aneurysms (5%). One hundred nine patients (94.8%) remained neurologically intact or unchanged from their initial clinical status. Five patients (4.3%) deteriorated as a result of immediate procedural complications. All these complications occurred in the first 50 patients treated in the series. No clinical complications were observed in the last 65 patients. In one patient, a partially embolized aneurysm ruptured 3 years postprocedure. In Groups 1 and 3, the average length of hospitalization was 3.3 days. CONCLUSIONS: The evolution of GDC technology has proved to provide safe treatment of incidental aneurysms (a morbidity rate of 0% was achieved in the last 65 patients). The topography of the aneurysm and the clinical condition of the patient did not influence final anatomical or clinical outcomes. The GDC technology also confers a positive economic impact by decreasing hospital length of stay and by eliminating the need for postembolization intensive care.

Adolescent↗
PubMed1999

Endovascular treatment of multiple intracranial aneurysms by using Guglielmi detachable coils.

OBJECT: The purpose of this paper is to present the authors' experience with Guglielmi detachable coil (GDC) embolization of multiple intracranial aneurysms and to evaluate the results of this therapy in single-stage procedures. METHODS: Clinical and angiographic evaluations were performed in 38 consecutive patients with multiple intracranial aneurysms treated by GDC embolization between March 1990 and October 1997. Twenty-nine patients presented with subarachnoid hemorrhage (SAH), four with mass effect, and five were asymptomatic. These 38 patients harbored 101 aneurysms, 79 of which were treated with GDCs, 14 by surgical clipping, and eight were left untreated. Of the GDC-treated lesions, a complete endovascular occlusion was achieved in 55 aneurysms (70%), and 24 (30%) presented neck remnants. Twenty-five patients (66%) underwent GDC embolization of more than one aneurysm in the first session. Eighteen (86%) of 21 patients with acute SAH underwent treatment for all aneurysms within 3 days after admission (15 of 21 in one session). Follow-up angiographic studies in 30 patients demonstrated an unchanged or improved result in 94% of the aneurysms (59 lesions) and coil compaction in 6% (four lesions). The overall clinical outcome was excellent in 34 patients (89%), good in one (3%), fair in one (3%), and death in two (5%). CONCLUSIONS: Endovascular treatment of multiple intracranial aneurysms, regardless of their location, with GDCs was performed safely in one session, even during the acute phase of SAH. Treatment of all aneurysms in one session protected the patient from rebleeding and eliminated the risk of mistakenly treating only the unruptured aneurysms.

Adolescent↗
PubMed1999

Intraarterial thrombolysis for treatment of acute stroke: experience in 26 patients with long-term follow-up.

BACKGROUND AND PURPOSE: Since the approval of intravenous tissue plasminogen activator for acute ischemic stroke, great interest has been generated in cerebral fibrinolysis. Our purpose was to assess long-term outcome and hemorrhagic risk in patients with anterior circulation ischemic stroke treated with intraarterial urokinase. METHODS: Twenty-six patients were treated within 6 hours of ictus; of these, 21 were followed up for an average of 23 months. Angiographic reperfusion was classified according to thrombolysis in myocardial infarction (TIMI) grades. The Rankin Scale (RS) and the modified Barthel Index (mod BI) were used as outcome measures (good outcome: RS = 0-2, mod BI = 16-20; poor outcome: RS = 3-5, mod BI < or = 15). RESULTS: Ten of the 21 patients (average age, 48 years) had a good outcome; three (average age, 71 years) had a poor outcome; eight patients (average age, 78 years) died. Partial/complete (successful) recanalization was observed in 11 of 26 patients and minimal or no (unsuccessful) recanalization in 15. Recanalization favored a better outcome: nine of 21 had successful recanalization, with a good outcome in seven; 12 of 21 had unsuccessful reperfusion, with poor outcome/death in nine. Poor outcome was noted in five patients with internal carotid artery (ICA) bifurcation occlusions, four of whom had unsuccessful recanalization and poor outcome or death. Hemorrhage occurred in 10 of the 26 patients, with clinical deterioration in three. The average dose of urokinase was higher in the hemorrhage group, and mortality was higher in patients who hemorrhaged. CONCLUSION: Intraarterial thrombolysis is feasible in the setting of acute stroke. Successful reperfusion is associated with a better outcome, and the prevalence of hemorrhage does not exceed that which occurs in the natural history of embolic stroke. Poor outcome or death is associated with nonrecanalization, older age, hemorrhage, and ICA bifurcation occlusions.

Acute Disease↗
PubMed1998

Nonadhesive liquid embolic agent for cerebral arteriovenous malformations: preliminary histopathological studies in swine rete mirabile.

OBJECTIVE: To assess acute and chronic histopathological changes observed in a swine arteriovenous malformation model after endovascular delivery of Embolyx E (Micro Therapeutics Inc., San Clemente, CA) and its organic solvent dimethyl sulfoxide (DMSO). To develop standard endovascular delivery techniques of Embolyx through microcatheters into swine rete mirabile (RMB). METHODS: Forty RMBs in 22 swine were used to analyze acute and chronic angiographic and histological changes after superselective delivery of Embolyx E and/or its organic solvent (DMSO). Four RMBs (two for DMSO and two for Embolyx E study) were used as control specimens. Angiographic and histological evaluations were obtained 18 days, 1 month, 3 months, and 6 months after the procedure. Particular attention was paid to the presence of focal or diffuse angionecrosis, arterial revascularization, and perivascular inflammatory response. RESULTS: Staged and/or continuous delivery of Embolyx E were performed through the DMSO-compatible microcatheters without untoward catheter "gluing." All subacute/chronic specimens embolized with Embolyx E showed no evidence of angiographic recanalization. Twelve RMBs were used in acute studies, and all specimens showed no evidence of angionecrosis or aggressive inflammatory reaction. Subacute and chronic (total, n = 14) histological examinations of the RMBs showed mild inflammatory response manifested by monocellular infiltration and scattered foreign body giant cell reaction. In the 9 of 14 subacute and chronic specimens, focal disruption of elastica was observed along with embolic materials. Fourteen RMBs in eight swine were used to determine the safety range for DMSO injection. Two RMBs were used as control specimens. Rapid intra-arterial delivery (0.5 ml/5-15 s, n = 6) of DMSO caused angiographic vasospasm and histological endothelial necrosis. Slow injection (0.5 ml/30-120 s, n = 8) of DMSO showed minimum or no angiographic vasospasm, minimal adventitial inflammatory response, and no clinical complications. CONCLUSION: Embolyx E, an occlusive and nonadhesive embolic agent, is capable of producing permanent occlusion of swine RMB with the development of mild intra- and perivascular inflammatory changes and no clinical complications. The slow endovascular delivery of DMSO produces no untoward angiographic, pathological, or clinical changes. A fast injection of DMSO causes endothelial necrosis and severe inflammatory response in the arterial wall. This embolic material seems to have appropriate biochemical, anatomic, and histopathological characteristics to be used in the treatment of cerebral arteriovenous malformations or vascular cranial base tumors.

Animals↗
PubMed1998

Direct arteriovenous fistulas (carotid-cavernous and vertebral-venous). Diagnosis and intervention.

Carotid-cavernous and vertebral-venous fistulas are direct arteriovenous fistulas. Their symptoms range from benign to extremely severe ophthalmologic or neurologic complications. Mechanism of symptoms is mostly related to venous drainage. Therapy is widely indicated, as today's endovascular techniques--using mostly detachable balloons and coils--have a high success rate and very few complications.

Arteriovenous Fistula↗
PubMed1997

Incidence of cerebral vasospasm after endovascular treatment of acutely ruptured aneurysms: report on 69 cases.

Cerebral vasospasm is the most common cause of morbidity and mortality in patients admitted to the hospital after suffering aneurysmal subarachnoid hemorrhage (SAH). The early surgical removal of subarachnoid clots and irrigation of the basal cisterns have been reported to reduce the incidence of vasospasm. In contrast to surgery, the endovascular treatment of aneurysms does not allow removal of subarachnoid clots. In this study the authors measured the incidence of symptomatic vasospasm after early endovascular treatment of acutely ruptured aneurysms with Guglielmi detachable coils (GDCs). Sixty-nine patients classified as Hunt and Hess Grades I to III underwent occlusion of intracranial aneurysms via GDCs within 72 hours of rupture. The amount of blood on the initial computerized tomography (CT) scan was classified by means of Fisher's scale. Symptomatic vasospasm was defined as the onset of neurological deterioration verified with angiographic or transcranial Doppler studies. Hypertensive, hypervolemic, hemodilution therapy, with or without intracranial angioplasty, was used to treat vasospasm after GDC placement. Symptomatic vasospasm occurred in 16 (23%) of 69 patients. The clinical grade at admission and the amount of blood on the initial CT were both associated with the incidence of subsequent vasospasm. At 6-month clinical follow-up examination, 12 of these 16 patients experienced a good recovery, two were moderately disabled, and two patients had died of vasospasm. In conclusion, the 23% incidence of symptomatic vasospasm in this series compares favorably with that found in conventional surgical series of patients with acute aneurysmal SAH. These results indicate that endovascular therapy does not have an unfavorable impact on cerebral vasospasm.

Acute Disease↗
PubMed1996

Endovascular embolization of superior hypophyseal artery aneurysms.

OBJECTIVE: Internal carotid artery aneurysms arising from the superior hypophyseal artery are frequently termed paraophthalmic or paraclinoid aneurysms, but they constitute a distinct anatomic entity. They are particularly amenable to endovascular treatment. METHODS: Between 1991 and 1995, we attempted treatment in 11 patients with superior hypophyseal artery aneurysms with Guglielmi detachable coil embolization and were successful in 10. Surgical exploration in seven of the patients was unsuccessful, three patients were considered to be at high risk for surgery or to have poor likelihood of surgical success by the referring neurosurgeon, and one patient refused operative clipping. Two aneurysms were giant (> 25 mm), three were large (10-25 mm), and six were small (< 10 mm). Of the six small aneurysms, two had wide necks (> 4 mm) and four had narrow necks (< or = 4 mm). RESULTS: There were no technical or clinical complications related to embolization. Immediate complete aneurysm obliteration was obtained in five aneurysms, all of which were small. Four of the remaining five aneurysms had obliteration of the dome and body, leaving only a small remnant neck. The remaining semifusiform aneurysm represented our single treatment failure. Recanalization occurred in only one patient; that patient had a giant aneurysm. Nine of the 10 patients for whom embolization was successful had good or excellent clinical outcomes; there were no clinical deteriorations attributable to embolization. CONCLUSION: We conclude that Guglielmi detachable coil embolization of superior hypophyseal artery aneurysms is an excellent treatment alternative, especially for smaller lesions.

Adult↗
PubMed1996

Treatment of large and giant fusiform intracranial aneurysms with Guglielmi detachable coils.

Results in nine patients with large or giant fusiform intracranial aneurysms that were treated with Guglielmi detachable coils (GDCs) are reported. There were six males and three females between the ages of 12 and 63. Four patients presented with subarachnoid hemorrhage (SAH) and four with mass effect; in one patient the aneurysm was asymptomatic and located in an arterial feeder of an arteriovenous malformation. Five aneurysms were supratentorial and four were in the posterior fossa. Five were giant and four were large. Selective occlusion with preservation of the parent artery was attempted in three cases, and complete occlusion of the aneurysm and the parent artery was performed in six patients. The tolerance to parent artery occlusion was assessed by angiography, balloon test occlusion, and amytal testing. Six aneurysms were permanently occluded and two partially recanalized. In one case, GDC embolization was not possible. The four patients who presented with SAH made an excellent clinical recovery. Three of the four patients presenting with mass effect recovered completely and one remained unchanged. The patient with an incidental aneurysm remained asymptomatic. There were no permanent complications. In conclusion, GDCs were useful for the occlusion of large and giant intradural fusiform aneurysms. Occlusion of the aneurysm and the parent artery afforded the greatest opportunity for a complete cure. Advantages of GDCs compared to balloons include: occlusion of a shorter segment of normal artery, no traction on the parent vessel, and safer and easier catheterization techniques.

Adult↗
PubMed1996

Laboratory simulations and training in endovascular embolotherapy with a swine arteriovenous malformation model.

We assessed the suitability of a swine experimental arteriovenous malformation model for laboratory simulations and training in endovascular embolotherapy. Embolizations with liquid glue or particles were performed in 10 animals. The parameters of injection (microcatheter position, concentration and volume of embolic agent, injection rate) were deliberately varied to simulate results that may be observed in clinical practice. A range of successful and less desirable therapeutic outcomes or complications was simulated. In one model, intravascular mean blood pressure in the "terminal feeder" rose after "nidus" embolization, consistent with observations in feeders of cerebral arteriovenous malformations. Experience in the technical aspects of embolotherapy was gained by repeated performances using this model. Simplicity of creation, clear angiographic visibility of feeders, a nidus and a draining vein, and hemodynamic similarities with cerebral arteriovenous malformations make this an attractive in vivo experimental model for learning the principles of embolotherapy, testing new embolic agents, and training/gaining experience in embolization techniques.

Animals↗