Origin Of Ophthalmic Artery Research Articles

Anatomic Nuances of the Ophthalmic Artery Origin from a Ventral Viewpoint: Considerations and Implications for Endoscopic Endonasal Surgery.

The origin of the ophthalmic artery is within the surgical field of endoscopic endonasal approaches (EEAs) to the suprasellar and parasellar regions. However, its anatomy from the endoscopic point-of-view has not been adequately elucidated. To highlight the anatomy of the ophthalmic artery origin from an endoscopic endonasal perspective. The origin of the ophthalmic artery was studied bilaterally under endoscopic visualization, after performing transplanum/transtubercular EEAs in 17 cadaveric specimens (34 arteries). Anatomic relationships relevant to surgery were evaluated. To complement the cadaveric findings, the ophthalmic artery origin was reviewed in 200 "normal" angiographic studies. On the right side, 70.6% of ophthalmic arteries emerged from the superior aspect, while 17.6% and 11.8% emerged from the superomedial and superolateral aspects of the intradural internal carotid artery, respectively. On the left, 76.5%, 17.6%, and 5.9% of ophthalmic arteries emerged from the superior, superomedial, and superolateral aspects of the internal carotid, respectively. Similar findings were observed on angiography. All ophthalmic arteries emerged at the level of the medial opticocarotid recess. Overall, 47%, 26.5%, and 26.5% of ophthalmic arteries (right and left) were inferolateral, inferior, and inferomedial to the intracranial optic nerve segment, respectively. On both sides, the intracranial length of the ophthalmic artery ranged from 1.5 to 4.5 mm (mean: 2.90±standard deviation of 0.74 mm). Awareness of the endoscopic nuances of the ophthalmic artery origin is paramount to minimize the risk of sight-threatening neurovascular injury during EEAs to the suprasellar and parasellar regions.

The clinical presentation and collateral pathway development of congenital absence of the internal carotid artery

ObjectiveThe objective of this study was to investigate the clinical presentation, risks, and collateral pathway development of the congenital absence of the internal carotid artery (ICA). MethodsSixty-four patients (10 new patients and 54 patients from the relevant literature) were studied. Data on demographic, clinical, and radiologic features were collected, followed by an analysis of the risks associated with ICA agenesis. ResultsThere were 31 male and 33 female patients whose ages ranged from 5 months to 75 years, with a mean age of 31.1 years. The range of clinical symptoms recorded included transient ischemic attack (17 patients), subarachnoid hemorrhage (12 patients), developmental delay (13 patients), asymptomatic (8 patients), and other symptoms (15 patients). All 64 patients presented with absence of unilateral or bilateral ICAs, as measured by cervical computed tomography angiography or magnetic resonance angiography. The carotid canal was absent in all patients on computed tomography of the base of the skull, and abnormal development of collateral circulation pathways was observed. Five patients presented with basilar artery dilation on angiography. Aneurysms were observed in the angiography results from 16 patients. Ten patients presented with variations in the ophthalmic artery origin (the ophthalmic artery originated from the ipsilateral middle meningeal artery in six patients and from the ipsilateral middle cerebral artery in four patients). ConclusionsFrom analysis of our 10 cases of ICA agenesis and our review of the relevant literature, we conclude that young patients with ICA agenesis may present with developmental delay, subarachnoid hemorrhage, or other developmental abnormalities, whereas older patients most commonly present with transient neurologic events. Complications of carotid agenesis are related to specific anatomic subtypes and the resulting collateral circulation development.

Ophthalmic artery occlusion after Pipeline Embolization Device placement with reconstitution of flow via an endoleak: a report of two cases

The Pipeline Embolization Device (PED) is a flow diverting stent used in the treatment of a wide variety of intracranial aneurysms. The device differs from traditional stents used in stent-assisted...

Ophthalmic artery originating from the anterior cerebral artery: anatomo-radiological study, histological analysis, and literature review

The ophthalmic artery has an anomalous origin in 2-3% of cases and rarely arises from the anterior cerebral artery. Herein, we provide the first anatomical, radiological, and histological description of such an anomalous origin, together with a literature review. During the anatomical dissection of an 81-year-old Caucasian male, the absence of the right ophthalmic artery in its usual location was evident from an endonasal transsphenoidal perspective. The specimen was then studied in detail, through multiple dissections, corrosion casting, high-resolution CT, and histological analysis. The English literature on anomalous origins of the ophthalmic artery was reviewed, together with reported associated pathologies. Anatomo-radiological analysis documented that the right ophthalmic artery arose from the inferior surface of A1 tract of the anterior cerebral artery (A1) and passed over the optic nerve in its subarachnoid tract. A meningo-ophthalmic artery was evident on the same side and reached the orbit through the superior orbital fissure. Histological examination of both internal carotid artery (ICA) walls documented a significantly decreased thickness of the tunica media and adventitia on the side of the anomalous ophthalmic artery, with a significantly different content of collagen types I and III. The literature review documented an association of aneurysms and anomalous ophthalmic arteries. To the best of our knowledge, this is the first anatomical report that includes a radiological and arterial wall analysis of a persistent ventral ophthalmic artery. The latter provides histological data that support the clinical evidence of a higher association of aneurysms with anomalous origins of the ophthalmic artery.

Pipeline Embolization Device for small paraophthalmic artery aneurysms with an emphasis on the anatomical relationship of ophthalmic artery origin and aneurysm.

OBJECTIVE Contemporary treatment for paraophthalmic artery aneurysms includes flow diversion utilizing the Pipeline Embolization Device (PED). Little is known, however, about the potential implications of the anatomical relationship of the ophthalmic artery (OA) origin and aneurysm, especially in smaller aneurysms. METHODS Four major academic institutions in the United States provided data on small paraophthalmic aneurysms (≤ 7 mm) that were treated with PED between 2009 and 2015. The anatomical relationship of OA origin and aneurysm, radiographic outcomes of aneurysm occlusion, and patency of the OA were assessed using digital subtraction angiography. OA origin was classified as follows: Type 1, OA separate from the aneurysm; Type 2, OA from the aneurysm neck; and Type 3, OA from the aneurysm dome. Clinical outcome was assessed using the modified Rankin Scale, and visual deficits were categorized as transient or permanent. RESULTS The cumulative number of small paraophthalmic aneurysms treated with PED between 2009 and 2015 at the 4 participating institutions was 69 in 52 patients (54.1 ± 13.7 years of age) with a male-to-female ratio of 1:12. The distribution of OA origin was 72.5% for Type 1, 17.4% for Type 2, and 10.1% for Type 3. Radiographic outcome at the last follow-up (median 11.5 months) was available for 54 aneurysms (78.3%) with complete, near-complete, and incomplete occlusion rates of 81.5%, 5.6%, and 12.9%, respectively. Two aneurysms (3%) resulted in transient visual deficits, and no patient experienced a permanent visual deficit. At the last follow-up, the OA was patent in 96.8% of treated aneurysms. Type 3 OA origin was associated with a lower rate of complete aneurysm occlusion (p = 0.0297), demonstrating a trend toward visual deficits (p = 0.0797) and a lower rate of OA patency (p = 0.0783). CONCLUSIONS Pipeline embolization treatment of small paraophthalmic aneurysms is safe and effective. An aneurysm where the OA arises from the aneurysm dome may be associated with lower rates of aneurysm occlusion, OA patency, and higher rates of transient visual deficits.

Visual outcomes with flow-diverter stents covering the ophthalmic artery for treatment of internal carotid artery aneurysms.

Flow-diverting stents can be used to treat intracranial aneurysms that are not amenable to treatment with coils. We analyzed ophthalmic consequences due to coverage of the origin of the ophthalmic artery by flow-diverting stents for the treatment of internal carotid artery aneurysms. From April 2009 to April 2013, the clinical and angiographic outcomes of all 28 patients treated for aneurysms with flow-diverting stents covering the origin of the ophthalmic artery were prospectively collected. The origin of the ophthalmic artery in relation to the target aneurysm was classified by using a 4-type classification. A complete ophthalmic examination was performed by a single ophthalmologist 48 hours before and 1 week after covering the ophthalmic artery. Ophthalmic artery patency was normal at the end of endovascular treatment in 24/28 cases (85.7%). With extensive ophthalmic examinations, 11 patients (39.3%) showed new ophthalmic complications. Patients with the ophthalmic artery originating from the aneurysm sac were at high risk for retinal emboli (4/5, 80%). Patients with the ophthalmic artery originating from the inner curve of the carotid siphon were at high risk for optic nerve ischemic atrophy (3/4, 75%). This prospective study shows that covering the ophthalmic artery with a flow-diverting stent is not without potential complications. Ophthalmic complications can occur but are often not diagnosed. The anatomic disposition of the ophthalmic artery in relation to the carotid siphon and aneurysm should be clearly understood because some configurations have a higher risk. When not required, covering of the ophthalmic artery by flow-diverting stents should be avoided.

Different ophthalmic artery origins: Embryology and clinical significance

This retrospective study gives a summary of ophthalmic artery (OA) variations to serve as guidelines for surgical interventionists and trainees. Pubmed and Medline searches were conducted. The OA usually arises intradurally (superomedial, anteromedial, or rarely superolateral) from the internal carotid artery (ICA). Rare extradural origin (primitive dorsal OA) (PDOA) remnant and extremely rare interdural origin (primitive ventral OA) (PVOA) remnant are of significance when sectioning the dural ring. Rarely, a persistent PDOA with ICA origin, or a PDOA remnant with inferolateral trunk origin, enters the orbit via the superior orbital fissure (SOF) for sole or partial orbital supply. Extremely rare, the PDOA and PVOA persist and form double OAs that arise from the ICA and run via the SOF and optic foramen. Occasionally, the OA arises from the middle meningeal artery (MMA), when both the PDOA and VDOA regress and enter the orbit via the SOF. Sole orbital supply via the external carotid artery (ECA), i.e. meningo-ophthalmic artery and/or MMA branches, or dual OAs (ECA and ICA origins) may occur. Other rare OA origins include anterior or posterior communicating artery; anterior or middle cerebral artery; basilar artery; posterior inferior cerebellar artery; and the carotid bifurcation. Primitive arteries (persistent or remnant), and/or abnormal anastomoses play pivotal roles in manifestations of OA variations. Of clinical importance are orbital collateral routes and dangerous extracranial-intracranial anastomoses. Awareness of OA origins and collateral routes is imperative for transarterial embolizations or infusion chemotherapy in the ECA territory to prevent visual complications.

Endovascular treatment of ophthalmic artery aneurysms: assessing balloon test occlusion and preservation of vision in coil embolization.

ICA-ophthalmic artery aneurysms have unique configurations corresponding to relative risks of ophthalmologic morbidities. Presented herein are clinical and radiologic outcomes of coil embolization in ophthalmic artery aneurysms. From January 2003 to September 2013, endovascular coiling was performed in 43 consecutive patients with ophthalmic artery aneurysms, each classified by the degree to which the ophthalmic artery was incorporated by the aneurysm and the contiguity between the ophthalmic artery entry and parent ICA. Clinical and radiologic outcomes of this approach were investigated, including the technical aspects of treatment and the efficacy of balloon test occlusion. Among 14 patients (32.6%, all ophthalmic artery types) undergoing balloon test occlusion before endovascular coiling, patent collaterals between the external carotid artery and ophthalmic artery were demonstrated in 12 (85.7%) and complete compromise of the ophthalmic artery (without affecting vision) occurred in 4 patients during coiling. Steam-shaped S-configured (67.9%) or straight microcatheters (17.8%) facilitated aneurysm selection in most of the superiorly directed ophthalmic artery aneurysms (n = 28), and steam-shaped pigtail microcatheters (85.7%) were useful in medially directed aneurysms (n = 14). Balloon protection (n = 22) was generally used to facilitate coiling, or a stent (n = 9) was alternatively deployed. Satisfactory aneurysmal occlusion was achieved through coil embolization in 37 lesions (86.1%). During follow-up of 35 patients (mean interval, 12.9 ± 9.4 months), only 1 instance (2.9%) of major recanalization was observed. If one tailors technical strategies, ophthalmic artery aneurysms are amenable to safe and effective endovascular coil embolization, which tends to be stable in follow-up. Balloon test occlusion may be helpful in devising treatment strategies to preserve vision when coiling ophthalmic artery aneurysms (especially those incorporating an ophthalmic artery origin) is done.

Ophthalmic Artery Arising from the Anterior Cerebral Artery and Concomitant Internal Carotid Artery Aneurysm: Report of a Case

Introduction: In 96% of subjects, the ophthalmic artery (OA) arises from the internal carotid artery (ICA). The OA and its branches make a significant contribution to the arterial supply of the retina in addition to external carotid artery branch collaterals. Other OA origins include the middle meningeal artery, the basilar artery, the posterior communicating artery and ICA bifurcation. The OA may also arise extradurally from the clinoidal segment or the intracavernous portion of the ICA and pass through the superior orbital fissure. OA originating from the anterior cerebral artery (ACA) is extremely rare. We present the unique case of a patient undergoing surgical treatment of a paraclinoidal ICA aneurysm, presenting with an OA originating from the ipsilateral ACA (A1 segment) (Fig. 1). Vascular embryogenesis and surgical anatomy are reviewed to understand this rare vascular anatomy combination.

Neuro-ophthalmic effects of stenting across the ophthalmic artery origin in the treatment of intracranial aneurysms.

OBJECT.: The benefits of treating intracranial aneurysms in the region of the anterior visual pathways are well understood. However, the adverse effects of endovascular stenting across the ophthalmic artery have received little attention. The authors reviewed their experience with patients who had stents deployed across the ophthalmic artery origin. Patients' medical charts and imaging studies were reviewed to identify all patients with a non-flow diverting stent deployed over the ophthalmic artery origin for the treatment of intracranial aneurysms. All patients with neuro-ophthalmic complaints were referred for formal ophthalmological evaluation. A total of 104 consecutive patients with 106 aneurysms were identified to meet criteria for inclusion in the study cohort. Preoperatively, 30 patients (29%) described headache symptoms and 32 patients (31%) reported visual complaints. Of the patients with preoperative headaches, 15 (54%) of 28 patients for whom follow-up was available experienced improvement in their symptoms. Of the patients with preoperative visual complaints, improvement was noted in 11 (41%) of the 27 patients for whom follow-up was available, 9 (33%) of 27 patients reported no change in visual symptoms, and 7 (26%) of 27 patients reported progression of symptoms. Visual field defects developing posttreatment were noted to occur in 8 (7.7%) of 104 patients: 3 with immediate postoperative retinal infarcts, 1 with perioperative hemianopia that resolved by the time of discharge, 1 with a subjective visual field defect, 1 with subjective migratory visual field defects, and 2 with nonspecific visual symptoms. Compressive symptoms from aneurysm mass effect were noted in 6 patients preoperatively, with 4 of those patients experiencing persistent worsening, resolution in 1 case, and no change in 1 case. One patient developed a novel cranial nerve palsy from mass effect in the immediate postoperative period. Deployment of stents across the ophthalmic artery origin for the treatment of intracranial aneurysms appears to be relatively safe with regard to visual outcomes. Neuro-ophthalmic complaint resolution rates were comparable to endovascular procedures that do not employ stents, with headache resolution rates comparable to coil-only aneurysm obliteration and low rates of retinal ischemic events. For patients presenting with mass effect, stent-assisted coiling appears to be less effective than microsurgery with decompression for relief of compressive symptoms.

Endovascular treatment of paraclinoid aneurysms: modified classification based microcatheter shaping technique

Objective To develop a modified classification to guide microcatheter shaping in endovascular management for paraclinoid aneurysms and to evaluate the efficiency of this technique.Methods From January 2009 to December 2011,consecutive 126 patients with 142 saccular paraclinoid aneurysms were treated with endovascular embolization at our institute.Paraclinoid aneurysms were classified as Type Ⅰ (ophthalmic artery aneurysms) and Type Ⅱ (superior hypophyseal artery aneurysm).Each type was further divided into two subtypes according to their relative position to an imaginary bisector that separated the origin of ophthalmic artery and posterior communicating artery.Ⅰ a and Ⅱ a referred to aneurysms arising from ICA proximal to the bisector,and Ⅰ b and Ⅱb referred to those aneurysms arising distal to the bisector.Recommended shapes of microcatheter for each subtype of the aneurysins were Ⅰ astraight,Ⅰ b-S shaped,Ⅱ a-C shaped (＜ 90 °) and Ⅱ b-primary curve (≥ 90°).The maneuverability of microcatheters was evaluated with an arbitrary score system.Results Of the 142 aneurysms,56 (39.4％)aneurysms were Type Ⅰ,while 86 (60.6％) were Type Ⅱ.24 aneurysms (16.9％) were managed with coil embolization,and 118 (83.1％) with stent-assisted coiling technique.Immediate angiography demonstrated complete occlusion in 62 (43.7％),neck remnant occlusion in 47 (33.1％) and residual aneurysm occlusion in 33 (23.2％) aneurysms.The microcatheter maneuverability scores ranked as Ⅰ b ＞Ⅱ a ＞ Ⅰ a ＞ Ⅱ b.The maneuverability of microcatheters in Type Ⅰ b was the least satisfactory (P ＜ 0.01).Conclusions A modified classification system of paraclinoid aneurysms may be used to guide microcatheter shaping during endovascular treatment. Key words: Paraclinoid aneurysms ; Endovascular treatment; Classification; Microcatheter

Aneurysmal Remodeling in the Circle of Willis after Carotid Occlusion in an Experimental Model

Carotid occlusions are associated with de novo intracranial aneurysm formation in clinical case reports, but this phenomenon is not widely studied. We performed bilateral carotid ligation (n=9) in rabbits to simulate carotid occlusion, and sham surgery (n=3) for control. Upon euthanasia (n=3 at 5 days, n=6 at 6 months post ligation, and n=3 at 5 days after sham operation), vascular corrosion casts of the circle of Willis (CoW) were created. Using scanning electron microscopy, we quantified gross morphologic, macroscopic, and microscopic changes on the endocasts and compared findings with histologic data. At 5 days, CoW arteries of ligated animals increased caliber. The posterior communicating artery (PCom) increased length and tortuosity, and the ophthalmic artery (OA) origin presented preaneurysmal bulges. At 6 months, calibers were unchanged from 5 days, PComs further increased tortuosity while presenting segmental dilations, and the OA origin and basilar terminus presented preaneurysmal bulges. This exploratory study provides evidence that flow increase after carotid occlusion produces both compensatory arterial augmentation and pathologic remodeling such as tortuosity and saccular/fusiform aneurysm. Our findings may have considerable clinical implications, as these lesser-known consequences should be considered when managing patients with carotid artery disease or choosing carotid ligation as a therapeutic option.

Flow diverter assisted coil embolization of a very small ruptured ophthalmic artery aneurysm

Small ruptured aneurysms present a unique problem to endovascular therapy. We report a case in which a patient presented with subarachnoid hemorrhage and a very small ruptured ophthalmic artery aneurysm,...

High incidence of ICA anterior wall aneurysms in patients with an anomalous origin of the ophthalmic artery: possible relevance to the pathogenesis of aneurysm formation

Surgery for aneurysms at the anterior wall of the internal carotid artery (ICA), which are also referred to as ICA anterior wall aneurysms, is often challenging. A treatment strategy needs to be determined according to the pathology of the aneurysm-namely, whether the aneurysm is a saccular aneurysm with firm neck walls that would tolerate clipping or coiling, a dissecting aneurysm, or a blood blister-like aneurysm. However, it is not always possible to properly evaluate the condition of the aneurysm before surgery solely based on angiographic findings. The authors focused on the location of the ophthalmic artery (OA) in determining the pathology of ICA anterior wall aneurysms. Between January 2006 and December 2012, diagnostic cerebral angiography, for any reason, was performed on 1643 ICAs in 855 patients at Saitama Medical Center. The authors also investigated the relationship between the origin of the OA and the incidence of ICA anterior wall aneurysms. The pathogenesis was also evaluated for each aneurysm based on findings from both angiography and open surgery to identify any correlation between the location where the OA originated and the conditions of the aneurysm walls. Among 1643 ICAs, 31 arteries (1.89%) were accompanied by an anomalous origin of the OA, including 26 OAs originating from the C3 portion, 3 originating from the C4 portion, and 2 originating from the anterior cerebral artery. The incidence of an anomalous origin of the OA had no relationship to age, sex, or side. Internal carotid artery anterior wall aneurysms were observed in 16 (0.97%) of 1643 ICAs. Female patients had a significantly higher risk of having ICA anterior wall aneurysms (p = 0.026). The risk of ICA anterior wall aneurysm formation was approximately 50 times higher in patients with an anomalous origin of the OA (25.8% [8 of 31]) than in those with a normal OA (0.5% [8 of 1612], p < 0.0001). Based on angiographic classifications, saccular aneurysms were significantly more common in patients with an anomalous origin of the OA than in those with a normal OA (p = 0.041). Ten of 16 patients with ICA anterior wall aneurysms underwent craniotomies. Based on the intraoperative findings, all 6 aneurysms with normal OAs were dissecting or blood blister-like aneurysms, not saccular aneurysms. There was a close relationship between the location of the OA origin and the predisposition to ICA anterior wall aneurysms. Developmental failure of the OA and subsequent weakness of the vessel wall might account for this phenomenon, as previously reported regarding other aneurysms related to the anomalous development of parent arteries. The data also appear to indicate that ICA anterior wall aneurysms in patients with an anomalous origin of the OA tend to be saccular aneurysms with normal neck walls. These findings provide critical information in determining therapeutic strategies for ICA anterior wall aneurysms.

An unusual superolateral origin of ophthalmic artery: an anatomic case report

If ophthalmic artery's (OphA) origin anomalies are frequent, the superolateral origin of the OphA was rarely described. During an aneurysmal surgery, a superolateral origin of the left OphA was found. This variation was associated with a sylvian aneurysm. The anatomical, embryological features, the neurosurgical implications of this origin such as treatment of carotid-ophthalmic aneurysm or intra arterial retinoblastoma chemotherapy are discussed. To the best of our knowledge, this is a very rare operative case of both superolateral origin and initial course of OphA.

Persistent dorsal ophthalmic artery and ophthalmic artery arising from the middle meningeal artery diagnosed by MR angiography at 3 T

A persistent dorsal ophthalmic artery (OA) is a rare variation that originates from the cavernous segment of the internal carotid artery (ICA) and enters the orbit via the superior orbital fissure (SOF). Occasionally, the OA also arises from the middle meningeal artery (MMA) and enters the orbit via the SOF. These two major variations of the OA have not been well described by magnetic resonance (MR) angiography. We evaluated their prevalence on MR angiography at 3 T. We retrospectively reviewed our database of MR angiographic images obtained using a 3 T imager. Of images of 846 patients, we evaluated those of 826 patients (1,652 OAs) with special attention to OA origin and its course into the orbit. We excluded images of the 20 because quality was insufficient to assess. We found 7 (0.42%) persistent dorsal OAs among 1,652 OAs (right/left, 6/1; male/female, 3/4). Twenty-four (1.45%) OAs arose from the MMA (right/left/bilateral, 11/5/4; male/female, 10/10), three of which also demonstrated a small normally branching OA. In one patient, we observed both right persistent dorsal OA and left OA arising from the MMA. Per OA, the prevalence of persistent dorsal OA was 0.42% and of OA arising from the MMA, 1.45%, with a tendency toward right-side predominance. OA arising from the MMA can be seen bilaterally; preprocedural knowledge of this variation is important because of the danger associated with endovascular procedures of the external carotid system when the OA arises from the MMA.

Measurement of Critical Structures around Paraclinoidal Area : A Cadaveric Morphometric Study.

ObjectiveAlthough removal of the anterior clinoid process (ACP) is essential surgical technique, studies about quantitative measurements of the space broadening by the anterior clinoidectomy are rare. The purposes of this study are to investigate the dimension of the ACP, to quantify the improved exposure of the parasellar space after extradural anterior clinoidectomy and to measure the correlation of each structure around the paraclinoidal area.MethodsEleven formalin-fixed Korean adult cadaveric heads were used and frontotemporal craniotomies were done bilaterally. The length of C6 segment of the internal carotid artery on its lateral and medial side and optic nerve length were checked before and after anterior clinoidectomy. The basal width and height of the ACP were measured. The relationships among the paraclinoidal structures were assessed. The origin and projection of the ophthalmic artery (OA) were investigated.ResultsThe mean values of intradural basal width and height of the ACP were 10.82 mm and 7.61 mm respectively. The mean length of the C6 lateral and medial side increased 49%. The mean length of optic nerve increased 97%. At the parasellar area, the lengths from the optic strut to the falciform liament, distal dural ring, origin of OA were 6.69 mm, 9.36 mm and 5.99 mm, respectively. The distance between CN III and IV was 11.06 mm.ConclusionWith the removal of ACP, exposure of the C6 segments and optic nerve can expand 49% and 97%, respectively. This technique should be among a surgeon's essential skills for treating lesions around the parasellar area.

Validating a Nonhuman Primate Model of Super-Selective Intraophthalmic Artery Chemotherapy: Comparing Ophthalmic Artery Diameters

Superselective intraophthalmic artery chemotherapy (SSIOAC) is being used for treatment of retinoblastoma; however, the hemodynamic consequences and toxicities are not fully known. We developed a nonhuman primate (NHP) model of SSIOAC and reported our clinical observations. For validation, we compared ophthalmic artery (OA) diameters between NHPs and children (<6 years). Endovascular cannulation of the right OA was performed three times each in six adult male Rhesus macaques. Angiographic OA images were obtained and measured, and postmortem OAs were histologically sectioned and measured. Retrospectively, computed tomography (CT) and magnetic resonance (MR) angiography images of the head in children and adolescents (as an adult reference) were used to measure the OA luminal diameter at its origin. The median angiographic diameter of treated NHP OA origins (n = 6) was 1.06 mm (range 0.94-1.56). Histologic measurements (8 of 12 NHP OAs) gave a median diameter of 1.09 mm (range 0.95-1.41). In 98 children (from 169 consecutive CT and MR angiography studies; median age 1.01 years, range 0.01-5.74), 186 OAs were measurable at the origin (median luminal diameter 1.28 mm, range 0.82-2.00; P = 0.16 for the angiographic NHP diameters versus pediatric cohort). Angiographic measurements of 34 OAs (of 20 consecutive studies of adolescents; median age 16.55 years, range 14.40-18.18) gave a median luminal diameter of 1.45 mm (origin, range 1.13-1.66; P < 0.0001, adolescent versus pediatric). Measurements of the OA luminal diameter at its origin were similar between our NHP and pediatric cohort, validating our NHP model for testing both the hemodynamic consequences and toxicities of SSIOAC.

Merci Retrievers as Access Adjuncts for Reperfusion Catheters

Expeditious, stable access in acute ischemic stroke is foundational for mechanical revascularization. Proximal vascular tortuosity and unfavorable anatomy may impede the access necessary for revascularization, particularly when large-caliber catheters are used. We describe an approach using the Merci retriever to gain stable catheter access for aspiration. To assess the technical feasibility of using the Merci retriever system as an access adjunct in acute ischemic stroke and tortuous ophthalmic segment anatomy. The acute ischemic stroke database was queried, and 3 patients presenting with acute ischemic stroke and tortuous proximal anatomy who were treated with mechanical thrombectomy and the Merci retriever as an access adjunct were identified. Patient charts and procedure reports were reviewed. In each of the patients, the ophthalmic segment of the internal carotid artery proved difficult to navigate. An appropriately sized Merci retriever was deployed in the M1 segment. Gentle tension on the retriever was applied, altering the angle at which the aspiration catheter navigated the ophthalmic segment, affording rapid access past the ophthalmic artery origin and into the target vessel. The 18 L microcatheter and retriever were withdrawn, followed by aspiration and clot maceration with the Penumbra aspiration system. Tortuous proximal anatomy may impede access to an occluded vessel. Use of tension on a deployed Merci retriever straightens the course of the wire, changing the angle that the aspiration catheter makes with the vessel. In the setting of unfavorable anatomy, this technique may be used to advance an aspiration catheter to the target lesion.

E-011 Merci retrievers as access adjuncts for reperfusion catheters: the grappling hook technique

Objective and ImportanceExpeditious and stable access in the setting of acute ischemic stroke is foundational to mechanical revascularization of large vessel occlusions of the cerebral vasculature, particular when using an...