Charles M. Cawley

Indocyanine green videoangiography in the management of dural arteriovenous fistulae.

OBJECTIVETo evaluate the usefulness of indocyanine green (ICG) videoangiography in the operative management of dural arteriovenous fistulae (dAVFs). METHODSIntraoperative ICG videoangiography was used as a surgical adjunct in 25 patients with cranial and spinal dural arteriovenous fistulae to identify the fistula and verify its complete obliteration. The findings on ICG videoangiography were compared with intraoperative and/or postoperative imaging. RESULTSAll dural arteriovenous fistulae were clearly identified by intraoperative ICG videoangiography and obliteration was documented in each case. Findings on ICG videoangiography correlated with intraoperative and/or postoperative imaging. CONCLUSIONICG videoangiography is a useful adjunct to the surgical management of dural arteriovenous fistulae for localization and confirmation of complete obliteration. The safety and ease of use make it an attractive modality. The surgeon can only evaluate what is visualized under the operating microscope and must therefore fully expose the venous drainage of the fistula to confirm obliteration.

Endovascular therapy of very small aneurysms of the anterior communicating artery: five-fold increased incidence of rupture.

BACKGROUND:Intraprocedural rupture is a dangerous complication of endovascular treatment. Small ruptured anterior communicating artery (ACoA) aneurysms and microaneurysms present a challenge for both surgical and endovascular therapies to achieve obliteration. An understanding of the complication rates of treating ruptured ACoA microaneurysms may help guide therapeutic options. OBJECTIVE:To report the largest cohort of ACoA microaneurysms treated with endovascular therapy over the course of the past 10 years. METHODS:We performed a retrospective review of 347 ACoA aneurysms treated in 347 patients at Cleveland Clinic and Emory University over a 10-year period. Patient demographics, aneurysmal rupture, size, use of balloon remodeling, patient outcomes, intraprocedural rupture, and rerupture were reviewed. RESULTS:Rupture rates were examined by size for all patients and subgroups and dichotomized to evaluate for size ranges associated with increased rupture rates. The highest risk of rupture was noted in aneurysms less than 4 mm. Of 347 aneurysms, 74 (21%) were less than 4 mm. The intraprocedural rupture rate was 5% (18/347) for ACoA aneurysms of any size. There was an intraprocedural rupture rate of 2.9% (8/273) among ACoA aneurysms greater than 4 mm compared with 13.5% (10/74) in less than 4-mm aneurysms. Procedural rupture was a statistically significant predictor of modified Rankin score after adjusting for Hunt and Hess grades (HH). CONCLUSION:ACoA aneurysms less than 4 mm have a 5-fold higher incidence of intraprocedural rerupture during coil embolization. Outcome is negatively affected by intraprocedural rerupture after adjusting for HH grade.

Advances in Surgical Approaches to Dural Fistulas

Dural arteriovenous fistulas are abnormal connections of dural arteries to dural veins or venous sinuses originating from within the dural leaflets. They are usually located near or within the wall of a dural venous sinus that is frequently obstructed or stenosed. The dural fistula sac is contained within the dural leaflets, and drainage can be via a dural sinus or retrograde through cortical veins (leptomeningeal drainage). Dural arteriovenous fistulas can occur at any dural sinus but are found most frequently at the cavernous or transverse sinus. Leptomeningeal venous drainage can lead to venous hypertension and intracranial hemorrhage. The various treatment options include transarterial and transvenous embolization, stereotactic radiosurgery, and open surgery. Although many of the advances in dural arteriovenous fistula treatment have occurred in the endovascular arena, open microsurgical advances in the past decade have primarily been in the tools available to the surgeon. Improvements in microsurgical and skull base approaches have allowed surgeons to approach and obliterate fistulas with little or no retraction of the brain. Image-guided systems have also allowed better localization and more efficient approaches. A better understanding of the need to simply obliterate the venous drainage at the site of the fistula has eliminated the riskier resections of the past. Finally, the use of intraoperative angiography or indocyanine green videoangiography confirms the complete disconnection of fistula while the patient is still on the operating room table, preventing reoperation for residual fistulas.Dural arteriovenous fistulas are abnormal connections of dural arteries to dural veins or venous sinuses originating from within the dural leaflets. They are usually located near or within the wall of a dural venous sinus that is frequently obstructed or stenosed. The dural fistula sac is contained within the dural leaflets, and drainage can be via a dural sinus or retrograde through cortical veins (leptomeningeal drainage). Dural arteriovenous fistulas can occur at any dural sinus but are found most frequently at the cavernous or transverse sinus. Leptomeningeal venous drainage can lead to venous hypertension and intracranial hemorrhage. The various treatment options include transarterial and transvenous embolization, stereotactic radiosurgery, and open surgery. Although many of the advances in dural arteriovenous fistula treatment have occurred in the endovascular arena, open microsurgical advances in the past decade have primarily been in the tools available to the surgeon. Improvements in microsurgical and skull base approaches have allowed surgeons to approach and obliterate fistulas with little or no retraction of the brain. Image-guided systems have also allowed better localization and more efficient approaches. A better understanding of the need to simply obliterate the venous drainage at the site of the fistula has eliminated the riskier resections of the past. Finally, the use of intraoperative angiography or indocyanine green videoangiography confirms the complete disconnection of fistula while the patient is still on the operating room table, preventing reoperation for residual fistulas.

Resolution of Oculomotor Nerve Palsy Secondary to Posterior Communicating Artery Aneurysms: Comparison of Clipping and Coiling.

BACKGROUND Previous studies have attempted to determine the best treatment for oculomotor nerve palsy (ONP) secondary to posterior communicating artery (PCoA) aneurysms, but have been limited by small sample sizes and limited treatment. OBJECTIVE To analyze the treatment of ONP secondary to PCoA with both coiling and clipping in ruptured and unruptured aneurysms. METHODS Data from 2 large academic centers was retrospectively collected over 22 years, yielding a total of 93 patients with ONP secondary to PCoA aneurysms. These patients were combined with 321 patients from the literature review for large data analyses. Onset symptoms, recovery, and time to resolution were evaluated with respect to treatment and aneurysm rupture status. RESULTS For all patients presenting with ONP (n = 414) 56.6% of those treated with microsurgical clipping made a full recovery vs 41.5% of those treated with endovascular coil embolization (P = .02). Of patients with a complete ONP (n = 229), full recovery occurred in 47.3% of those treated with clipping but in only 20% of those undergoing coiling (P = .01). For patients presenting with ruptured aneurysms (n = 130), full recovery occurred in 70.9% compared with 49.3% coiled patients (P = .01). Additionally, although patients with full ONP recovery had a median time to treatment of 4 days, those without full ONP recovery had a median time to treatment of 7 days (P = .01). CONCLUSION Patients with ONP secondary to PCoA aneurysms treated with clipping showed higher rates of full ONP resolution than patients treated with coil embolization. Larger prospective studies are needed to determine the true potential of recovery associated with each treatment. ABBREVIATIONS EUH, Emory University HospitalIQR, interquartile rangeJHU, Johns Hopkins UniversitymRS, modified Rankin ScaleONP, oculomotor nerve palsyPCoA, posterior communicating arterySAH, subarachnoid hemorrhage.

Pial Arteriovenous Fistula Resulting from Ventriculostomy

OBJECTIVE Ventriculostomy complications are well documented in the literature. We report the first known example of an arteriovenous fistula created during passage of a ventriculostomy catheter for the treatment of hydrocephalus. METHODS A 47-year-old female patient initially presented with a subarachnoid hemorrhage and an anterior communicating artery aneurysm. The patient underwent coil embolization followed by a ventriculostomy catheter for hydrocephalus. After recovery, a follow-up angiogram demonstrated a new arteriovenous fistula at the site of the ventriculostomy. A craniotomy was performed at the site of the ventriculostomy burr-hole site. Indocyanine green videoangiography confirmed the site of the fistula. RESULTS The fistulous point was coagulated and divided and confirmed with both indocyanine green videoangiography and intraoperative diagnostic angiography. The patient recovered without deficit. CONCLUSION This is the first reported case of a pial arteriovenous fistula from a ventriculostomy catheter. The formation of a fistula can occur from trauma to cortical arteries and veins at the pial entry site. Although rare, vascular injury and subsequent fistula formation may form in patients in whom catheter tract hemorrhages occur after catheter placement.

Indocyanine Green Videoangiography for Confirmation of Bypass Graft Patency

OBJECTIVE The aim of the study is to determine the efficacy of indocyanine green (ICG) videoangiography for confirmation of vascular anastomosis patency in both extracranial-intracranial and intracranial-intracranial bypasses. METHODS Intraoperative ICG videoangiography was used as a surgical adjunct for 56 bypasses in 47 patients to assay the patency of intracranial vascular anastomosis. These patients underwent a bypass for cerebral ischemia in 31 instances and as an adjunct to intracranial aneurysm surgery in 25. After completion of the bypass, ICG was administered to assess the patency of the graft. The findings on ICG videoangiography were then compared to intraoperative and/or postoperative imaging. RESULTS ICG provided an excellent visualization of all cerebral arteries and grafts at the time of surgery. Four grafts were determined to be suboptimal and were revised at the time of surgery. Findings on ICG videoangiography correlated with intraoperative and/or postoperative imaging. CONCLUSION ICG videoangiography is rapid, effective, and reliable in determining the intraoperative patency of bypass grafts. It provides intraoperative information allowing revision to reduce the incidence of technical errors that may lead to early graft thrombosis.

Carotid cavernous fistula after Pipeline placement: a single-center experience and review of the literature

Objective Carotid cavernous fistula (CCF) development after Pipeline Embolization Device (PED) treatment of cavernous carotid aneurysms (CCA) can be a challenging pathology to treat for the neurointerventionalist. Methods A database of all patients whose aneurysms were treated with the PED since its approval by the Food and Drug Administration in 2011 was retrospectively reviewed. Demographic information, aneurysm characteristics, treatment technique, antiplatelet regimen, and follow-up data were collected. A literature review of all papers that describe PED treatment of CCA was then completed. Results A total of 44 patients with 45 CCAs were identified (38 women, 6 men). The mean age was 59.9±9.0 years. The mean maximal aneurysm diameter was 15.9±6.9 mm (mean neck 7.1±3.6 mm). A single PED was deployed in 32 patients, with two PEDs deployed in 10 patients and three PEDs in 3 patients. Adjunctive coiling was performed in 3 patients. Mean follow-up duration based on final imaging (MR angiography or digital subtraction angiography) was 14.1±12.2 months. Five patients (11.4%) developed CCFs in the post-procedural period after PED treatment, all within 2 weeks of device placement. These CCFs were treated with a balloon test occlusion followed by parent artery sacrifice. Our literature review yielded only three reports of CCFs after PED placement, with the largest series having a CCF rate of 2.3%. Conclusions CCF formation is a known risk of PED treatment of CCA. Although transvenous embolization can be used for treating CCFs, parent artery sacrifice remains a viable option on the basis of these data. Studies support the view that adjunctive coiling may have a protective effect against post-PED CCF formation. None of the coiled aneurysms in our database or in the literature have ruptured. Follow-up data will lead to a better understanding of the safety profile of the PED for CCA.

Experience with coil embolization of previously clipped aneurysms presenting with rupture.

Introduction Endovascular coil embolization has an established role alongside microsurgical clipping in the treatment of aneurysms. We studied previously clipped aneurysms that presented as subarachnoid hemorrhage and were treated by coil embolization. Methods A retrospective review was performed of two prospectively maintained databases from two institutions (Cleveland Clinic, Emory University) that spanned 12 years. Results Seven patients were identified (mean age 56.9 years) who had previously undergone surgical clipping for aneurysm obliteration; six (86%) were previously ruptured. Patients presented with aneurysm rupture with a mean time of 11.5 years (range 4 months to 20 years) following surgical treatment. Aneurysm location included anterior communicating artery (n=4), posterior communicating artery (n=1), internal carotid artery terminus (n=1) and anterior choroidal (n=1). Three patients presented in Hunt and Hess (HH) grade 1, one in HH2, two in HH3 and one in HH4. Four of the patients underwent unassisted coil embolization while balloon assistance was employed in three. Angiographic results were as follows: complete occlusion (n=3; 42.9%) and residual neck (n=4; 57.1%). There were no intraprocedural complications. Conclusion Aneurysm rupture following surgical obliteration is a rare event and may occur remote from the initial treatment. Endovascular embolization with or without balloon assistance can be safely employed in cases of aneurysm recurrence rupture following surgical treatment with satisfactory angiographic treatment.

Endovascular treatment of an aneurysm of a persistent primitive hypoglossal artery with complete resolution of brainstem compressive symptoms: case report.

BACKGROUND AND IMPORTANCE:Aneurysms of the posterior circulation may manifest with neurological deficits related to mass effect on the brainstem. We present an unusual case of an aneurysm resulting in selective lower-extremity weakness and gait instability. CLINICAL PRESENTATION:A 61-year-old man presents with progressively worsening gait instability over the course of several months. A magnetic resonance image and computed tomographic angiogram demonstrate a persistent hypoglossal artery associated with an aneurysm invaginating into the pontomedullary junction. The patient manifested only lower-extremity symptoms. An endovascular approach through the right internal carotid artery and persistent primitive hypoglossal artery was assayed, coiling off the aneurysm with complete angiographic occlusion. One month after the procedure, the patient reported marked improvement in symptoms with residual difficulty walking. At the 1-year postprocedure interval, he reported nearly complete resolution of symptoms. CONCLUSION:Endovascular therapy of an aneurysm invaginating into the brainstem is safe and efficacious.

Reduced Efficacy of the Pipeline Embolization Device in the Treatment of Posterior Communicating Region Aneurysms with Fetal Posterior Cerebral Artery Configuration

BACKGROUND Aneurysms at the origin of the posterior communicating artery (PcommA) have been demonstrated to be effectively treated with the pipeline embolization device (PED). Much less is known about the efficacy of the PED for aneurysms associated with a fetal posterior cerebral artery (fPCA) variant. OBJECTIVE To study PED treatment efficacy of PcommA aneurysms, including fPCA aneurysms. METHODS A prospectively maintained university database of aneurysm patients treated with the PED was retrospectively reviewed. Demographics, treatment details, and imaging were reviewed for all PcommA and fPCA aneurysms. RESULTS Out of a total of 285 patients treated with PED, 50 patients (mean age 57.5 ± 12.2 yr, 42 females) with unruptured PcommA (9 fPCA) aneurysms were identified. Mean follow-up duration was 14.0 ± 11.6 mo (48 patients). Roy-Raymond class I occlusion on follow-up magnetic resonance or catheter angiography (mean time 11.7 ± 6.8 mo) was achieved in 30 patients (62.5%), class II occlusion in 11 patients (22.9%) and class III occlusion in 7 patients (14.5%). The PcommA was occluded in 56% of patients without any clinical symptoms. No deaths or permanent neurological complications occurred. In fPCA aneurysms, class I occlusion was seen in 1 patient, class 2 occlusion in 2 patients, and class III occlusion in 6 patients. Multivariate analysis revealed an independent association between incomplete occlusion and fPCA configuration (OR 73.65; 95% CI: 5.84-929.13; P = .001). CONCLUSION The PED is a safe and effective treatment for PcommA aneurysms, although fetal anatomy should increase consideration of traditional endovascular techniques or surgical clipping.