A narrative review of unruptured ophthalmic aneurysms: current evidence for management based on emerging knowledge

Introduction

Background

Ophthalmic aneurysms are intracranial aneurysms (IAs) that arise between the distal border of the cavernous internal carotid artery (ICA) segment, just proximal to the ophthalmic artery (OphA) ostium, to the origin of the posterior communicating artery (1). Aneurysms may arise close to the origin of the OphA or from the artery itself. Most ophthalmic aneurysms originate from the intradural ICA, although, in 2–18% of cases, they are extradural, since the OphA can arise from the low clinoid segment (2,3).

Treatment options include microsurgical clipping, and a range of endovascular techniques, such as coil embolization, flow-diverting devices, and the combination of coiling with stenting. Due to the complex anatomy in this region—including the anterior clinoid process, optic apparatus, cavernous sinus, and ICA branches—ophthalmic aneurysms pose significant technical challenges for most neurosurgeons. As a result, endovascular treatment (EVT) has become increasingly favored, owing to its accessibility, the absence of critical perforating vessels, and ongoing advances in endovascular device technology.

Rationale and knowledge gap

Ophthalmic aneurysms have a very low risk of rupture compared with other IAs locations (4). Nonetheless, the preventive treatment of small, incidentally discovered, unruptured ophthalmic aneurysms remains controversial (4,5), and no consensus exists regarding the optimal management of larger unruptured lesions (6,7). A recent review by Wang and Yu (8) provided an overview of endovascular techniques for paraophthalmic aneurysms and briefly mentioned microsurgical clipping. Our review expands upon this by integrating both microsurgical and endovascular strategies, incorporating more recent evidence, and offering a structured overview intended to guide clinical practice.

Objective

This review specifically focuses on unruptured ophthalmic aneurysms. The objective is to summarize and critically evaluate the current evidence regarding their epidemiology and natural history, risk of rupture, and available treatment options. Emphasis is placed on the role of evolving endovascular techniques and recent advances in device technology, with the aim of guiding clinical decision-making in the absence of standardized treatment protocols. We present this article in accordance with the Narrative Review reporting checklist (available at https://jni.amegroups.com/article/view/10.21037/jni-25-36/rc).

Methods

A structured literature search was conducted to identify studies on the management of unruptured ophthalmic aneurysms. Electronic databases, including PubMed, Scopus, and Google Scholar, were queried using key search terms such as “ophthalmic artery aneurysms” OR “paraophthalmic segment” OR “periophthalmic aneurysm” AND “paraclinoid aneurysms” AND “unruptured”, AND “management”, AND “treatment”, AND “complication”, AND “retinal artery”, AND “follow-up”. The search was limited to articles published in English between 2014 and 2025.

Inclusion criteria consisted of studies focusing on risk assessment, clinical outcomes, and treatment approaches for unruptured ophthalmic aneurysms. Exclusion criteria included ruptured ophthalmic aneurysm, peripheral type aneurysms originating from the OphA, in vitro studies, animal studies, and those lacking sufficient data on management strategies (Table 1, Table S1).

Evidence from case reports, observational studies, and expert opinion articles was summarized to provide an updated overview of the current management practices for unruptured ophthalmic aneurysms.

Epidemiology and natural history

Ophthalmic aneurysms represent 7.5–10% of all IAs (4,5,9). They have a notable female predilection, with hormonal factors likely playing significant role in their higher incidence at this specific location (4,10).

In a study by Chiaroni et al. (4), which evaluated 604 IAs, ophthalmic aneurysms accounted for 14.9% of unruptured IAs (UIAs) (the second most common aneurysm location) and 1.2% of ruptured IAs (second least common aneurysm location). The mean size of unruptured ophthalmic aneurysms was 5.4 mm (average compared with other UIAs), while the mean size of ruptured ophthalmic aneurysms was 12.7 mm (the largest among all locations). Similarly, Jeon et al. (5), reported a low annual rupture rate of 0.12% and an annual growth rate of 1.01% for incidental, small (≤5 mm), paraclinoid unruptured aneurysms over a total of 1,675.5 aneurysm-years, with risk factors for rupture and growth including aneurysms ≥4 mm, branch-related lesions, hypertension and multiple aneurysms.

Regardless of aneurysm rupture, patients may experience non-specific symptoms such as headache of varying severity, along with signs and symptoms of optic nerve (ON) and/or chiasma dysfunction due to mass effect. These can include impaired visual acuity, progressive or sudden visual field deficits (most commonly hemianopia), and diplopia, particularly when the aneurysm fundus is 5 mm or larger (11-13). The pathophysiology of the visual impairment remains unclear, with four potential mechanisms suggested as the primary cause: direct compression of the visual pathway by the aneurysm, especially in presence of aneurysm wall calcification and intraluminal thrombus; pulsation over the fundus of the aneurysm, which could explain the favorable outcome of endovascular occlusion; vascular compromise due to occlusion or kinking of the OphA; indirect compression of the ON against the optic canal (14).

Classifications

Ophthalmic aneurysms can be classified based on the relationship between the OphA and the aneurysm, particularly when covered by a flow-diverting stent (FDS). According to Rouchaud et al. (15), the OphA origin is categorized into four types:

• Type A: OphA originates from the aneurysm sac.
• Type B: OphA originates close to or from the neck of the aneurysm.
• Type C: OphA originates from the inner curve of the carotid siphon.
• Type D: OphA is not involved in the aneurysm but is covered by the stent.

This classification is particularly useful for evaluating the positioning and involvement of the OphA relative to the aneurysm, which is crucial for treatment planning. Ophthalmic aneurysms are also categorized by size as small (<7 mm), medium (7–12 mm), large (13–24 mm), and giant (≥25 mm) (16).

Summary of current evidence

Interpretation of published outcomes is complicated by substantial heterogeneity across studies, including differences in patient selection, aneurysm morphology, treatment techniques, and follow-up periods. In addition, many older reports may be less applicable in the current era of improved devices and techniques, which have substantially altered both safety and efficacy profiles. Where possible, we stratified reported results according to aneurysm size, morphology, and clinical presentation to provide a clearer summary of the available evidence.

Management approaches

Currently, there are no standardized guidelines for managing unruptured ophthalmic aneurysms. Deciding on preventive treatment for asymptomatic, small, regularly shaped ophthalmic aneurysms is particularly challenging, as it requires balancing the potential benefits of intervention alongside the risks associated with treatment, especially since these aneurysms grow more slowly and have a lower rupture risk compared to other intra-dural aneurysms. Recent studies suggest that conservative treatment should be the first choice for this subgroup, with close monitoring being appropriate for patients with high-risk factors, such as neck diameter ≥4 mm, hypertension, arterial branch-related aneurysms [Type A and B (15)], and multiple aneurysms (4,5). This watchful waiting strategy could include a first follow-up within 6 to 12 months, followed by subsequent yearly or biennial imaging once stability is documented. It may be appropriate to discontinue further scheduled follow-up when the patient’s age or medical comorbidities reach a point where invasive interventions pose an excessive risk or provide minimal benefits (17). Time-of-flight magnetic resonance angiography (TOF-MRA) should be preferred for repeated imaging over computed tomography angiography (CTA), as it doesn’t require intravenous contrast and avoids X-ray radiation (17). At the same time, patients should be encouraged to adopt lifestyle modifications to address risk factors, such as smoking cessation and hypertension control (18).

The decision to treat small, asymptomatic unruptured ophthalmic aneurysms requires careful evaluation of both aneurysm-specific and patient-related risk factors. Features associated with higher rupture risk include irregular shape, presence of blebs, fusiform or dissecting morphology, and proven aneurysm growth (19,20). Patient factors such as a history of subarachnoid hemorrhage (SAH) from another aneurysm, age under 50 years, Japanese ethnicity, hypertension, and the presence of multiple aneurysms should also be considered (18,21). Conservative management with imaging surveillance is generally appropriate in the absence of these risk factors.

Treatment is typically indicated for large aneurysms (13–24 mm) or for symptomatic cases, especially when mass effect on the optic apparatus or cranial nerves is present (13,16).

The primary goal is to preserve visual function whilst ensuring the aneurysm is completely excluded in the long-term to avoid SAH and aneurysm growth. A multidisciplinary discussion involving neurovascular surgeons and interventional neuroradiologists is essential for determining the most effective treatment tailored to each individual patient. Treatment options include sole coil-embolization, balloon-assisted coiling (BAC), stent-assisted coiling (SAC), FDS with or without adjunctive coiling, intrasaccular flow diverters, and microsurgical clipping. For each treatment of these approaches, we discuss the selection criteria, potential limitations, outcomes to date, and associated complications. Key comparative features of the different management strategies are outlined in Table 2.

Endovascular coiling

Ophthalmic aneurysms can be challenging to access due to their unique orientations, along with the sharp curvature of the carotid siphon proximal to the aneurysm and larger caliber of the paraophthalmic ICA lumen. As a result, maintaining a stable microcatheter position during coil embolization may be difficult, with the two primary technical issues being microcatheter aneurysm catheterization and the kickback during coil insertion (22).

Shaping the microcatheter can greatly aid procedural success. Suggestions include an S-shaped microcatheter for selecting superiorly directed aneurysm, and ‘loop-shaped technique’ (deflecting the wire and catheter off the wall of the aneurysm itself) in large/giant aneurysms (23-25). More recently, patient specific shaping of microcatheter using 3D printing has emerged, potentially reducing procedure time and optimizing coiling cost efficiency, however availability of the equipment and expertise in using it will remain a limiting factor (26). Despite these techniques, simple coiling of large ophthalmic aneurysm can result in incomplete packing or coil protrusion. For these reasons, conventional simple coiling for unruptured ophthalmic aneurysms is usually performed only for small, narrow-necked aneurysms (<4 mm) (27).

For larger aneurysms (small and medium types) with a wide neck (>4 mm) or a dome-to-neck ratio <2, balloon-assisted or SAC is typically employed (28-30). The main advantage of balloon-assisted coiling over stenting is that it does not require dual antiplatelet therapy (DAPT). During coiling, the balloon should be intermittently fully inflated to promote neck remodelling and prevent coils from protrusion (30). In addition, balloon assistance allows protective inflation in case of intra-procedural perforation. However, some authors argue that full inflation of the balloon at the aneurysm neck may create a mechanical conflict with the coil-delivering microcatheter, potentially leading to incomplete coiling or even injury to the aneurysm wall. They suggest a modified BAC technique with partial balloon inflation to improve outcomes by stabilizing the microcatheter and preventing the kick-back of the microcatheter tip from the aneurysm (31).

If the aneurysm neck is very wide and coiling cannot secure the aneurysm, SAC may be required. All available low-profile stents can be delivered through double-lumen balloons such as the Eclipse 2 L (Balt Extrusion, Montmorency, France) or Scepter (C or XC) (MicroVention, Aliso Viejo, CA, USA) (31,32). This approach, known as the combined remodeling technique (CRT), involves deploying a stent through the balloon and provides several advantages: it enables angioplasty in cases of stent malapposition, facilitates balloon-assisted neck remodeling, allows immediate hemostasis in the event of intra-procedural perforation, and offers flexibility in bailout scenarios such as branch occlusion or coil protrusion, thereby reducing the need for additional maneuvers (32). The stent also provides the benefit of reducing aneurysm recurrence by promoting endothelialization at the aneurysm neck (20).

In addition to balloon- and stent-assisted methods, the double catheter technique has been reported as a useful strategy for treating wide-neck aneurysms, particularly those that are large or complex (24,25). This approach involves placing two microcatheters into the aneurysm sac, allowing alternating coil deployment. By enabling simultaneous or sequential coil placement from different angles, the technique improves coil stability, facilitates dense packing, and reduces the risk of coil protrusion into the parent artery. It may therefore be particularly valuable in cases where single-catheter coiling is unstable or insufficient.

In elective cases, patients should initiate DAPT prior to the procedure, with continuation for a prescribed duration post-procedure depending on the type of stent used, followed by monotherapy for an additional period as determined by the operator (8). In the setting of SAH, balloon-assisted and stent-assisted coiling have demonstrated better outcomes in terms of durability compared to sole coil embolization. In a study by Kim et al. (28), the recurrence rate was 21.3% for simple coiling versus 2.7% for stent-coiling, with the latter exhibiting a higher rate of progressive occlusion. A long-term follow-up study reported an adequate occlusion rate of 94.9% and a complete occlusion rate of 60% after SAC (20). Similarly, adequate occlusion rates of 99.9% and complete occlusion rates of 71.4–75.8% were reported after balloon coiling (31,33).

Endovascular flow-diversion

FDS serve as a scaffold for endothelial cell proliferation, enabling the exclusion of the aneurysm sac from circulation without the need for catheterization or coiling. This approach reduces the risk of intra-procedural rupture, lowers the recanalization rate, and avoids the potential mass effect associated with coiling (8).

Flow diversion is particularly applicable at the para-ophthalmic ICA segment due to its caliber, accessibility, and the relative absence of important perforators, which facilitates device navigation and reduces the risk of ischemic complications (34). OphA aneurysms in general are anatomically suitable for endovascular flow disruption given their dome-to-neck ratio and orientation (5,6,34,35). Several studies have demonstrated the efficacy of FDS in this region, and they can be considered the first choice for wide-neck, large or giant, fusiform or dissecting, unruptured ophthalmic aneurysms (34-40). Additionally, since covering the OphA with a FDS appears to be relatively well tolerated, ophthalmic aneurysms which incorporate the OphA may benefit from the flow diversion approach (36,41,42). This is particularly relevant as efforts to preserve the OphA can lead to incomplete coil deployment. The use of FDS also extends to partially thrombosed ophthalmic aneurysms, where endovascular coiling may cause coil migration into the thrombus, potentially reopening the aneurysm lumen (43). Furthermore, flow-diversion is a suitable option for managing recurrences or residual aneurysms (37,38).

For challenging cases, especially those larger than 10 mm in diameter or fusiform in shape, adjunctive coiling can be crucial in minimizing the effects of acute thrombosis and reducing the risk of rupture. In these cases, where there is a risk of the FDS shifting or prolapsing, coiling can also provide additional support (34,36). As with other stents, patients should receive DAPT prior to the procedure, which should be continued followed by single antiplatelet therapy post-procedurally for a defined duration (8,39).

By redirecting blood flow away from the aneurysm, FDS create a favorable environment for progressive intraluminal thrombosis and saccular shrinkage. Consequently, aneurysm occlusion occurs in a delayed fashion (39). In a study by Kunert et al. involving 52 patients with 65 unruptured ophthalmic aneurysms, the complete occlusion rates were 12%, 73%, and 95% immediately post-procedure, at 6 months, and at 5 years, respectively. These outcomes were similar in both the FDS and FDS + coiling groups (40). Other series have reported long-term complete occlusion rates of 89% to 96% (38,39).

Endovascular intrasaccular flow-diversion

Intrasaccular flow disruptors are relatively new devices developed to address the challenges of treating wide-neck complex aneurysms with unfavorable anatomy for stent deployment or microsurgical clipping. Designed to be placed entirely within the aneurysm sac, they combine the benefits of intraluminal flow diversion, flow disruption, and mechanical occlusion. Since no foreign material remains in the parent vessel, their primary advantage is the avoidance of long-term antiplatelet therapy (44).

The Woven endoBridge (WEB, Microvention, Aliso Viejo, CA, USA) was introduced into clinical practice in 2011 and remains the most studied and widely used amongst those currently available. Although only three small case series on the treatment of ophthalmic aneurysms exist, the results are promising, with the potential for better preservation of the OphA ostium in type A and type B aneurysms (45-47). Additionally, the hemodynamic forces at the OphA may also promote more stable sac occlusion and safer outcomes with intrasaccular flow diverters (47). These potential advantages should encourage further studies with larger patient cohorts and long-term follow-up to better assess the feasibility and safety of this treatment.

Data on the treatment of ophthalmic aneurysms are still limited for other intrasaccular devices, such as the Contour Neurovascular System^TM (Cerus Endovascular, Fremont, California, USA), the Neqstent^TM CoilAssisted Flow Diverter (Cerus Endovascular), and the Artisse^TM Embolization System (Medtronic, Dublin, Ireland). However, these devices exhibit promising design characteristics and may help address specific challenges, including wide aneurysms with shallow depth, highly irregular shapes, or previous treatment (44).

Endovascular complications and clinical outcomes

A recent meta-analysis demonstrated that EVT results in a good prognosis for ophthalmic aneurysm (7). Favorable clinical outcomes, defined as a modified Rankin Scale (mRS) score of 0–2, have been reported in up to 96.6% and 98.2% of cases treated with SAC and FDS, respectively (40,48).

The decision to treat ophthalmic aneurysms with EVT must consider the risk of hemorrhagic and thromboembolic complications, with the latter being primarily affecting visual outcomes. The reported incidence of post-treatment visual complications ranges from 0 to 9.3% for patients treated with coiling (48-51), and from 0 to 3.8% for those treated with FDS (40,42,48,52-54). A recent metanalysis by Touzé et al. found an acceptable rate of iatrogenic visual complications with only 3.0% of new visual symptoms after the treatment of ophthalmic aneurysms by FDS (42).

The most common subtypes of visual complications include amaurosis fugax and visual field deficits (50). Retinal and/or optic ischemia may occur due to varying degrees of unpredictable thromboembolism originating from the orifice of the OphA during endovascular manipulation, or because of small embolic material generated within the thrombosing aneurysmal sac that subsequently migrates to the OphA (49,53-55). According to Michishita et al., the origin of the OphA is a key factor in postoperative visual complications, with the Dome and Shared types associated with a higher risk of retinal embolism compared to the Separate type (10). Another possible mechanism is decreased perfusion resulting from complete occlusion of the OphA, particularly when collateral circulation is insufficient (50,54). In cases of ophthalmic aneurysms where the anticipated risk of OphA sacrifice is high during EVT, some authors recommend selectively performing a balloon test occlusion (BTO) to evaluate collateral flow to the OphA (51,56).

Adequate collateral supply from external carotid branches occurs in 84–93% of cases (49,53,56), while OphA occlusion and caliber reduction are reported in 7.1–25% and 8.3–18.5% of cases, respectively (41,57-59) yet clinical sequelae are rare, suggesting OphA preservation is often not essential to prevent retinal ischemia (38,39,49,52,60).

Aneurysm size affects the risk of complications. Thromboembolic events, such as in-stent thrombosis or distal cerebral ischemia, occur more frequently in large aneurysms (7.4%) compared to small ones (1%). Hemorrhagic complications, on the other hand, are observed in 0.7% of small aneurysms and none of the large aneurysms (61). Miller et al. reported a 5% rate of permanent neurological deficits following SAC, but none after treatment with flow diverter stents (62). Similarly, Di Maria et al. found overall complication rates of 6.6% in the coiling group and 7.8% in the flow diverter stent group. The rates of permanent morbidity were 1.6% for coiling and 3.9% for FDS, with no statistically significant difference between the two groups (63).

Microsurgical clipping

Microsurgical clipping of ophthalmic aneurysms presents unique technical challenges due to their relationship with critical neurovascular structures, including the optic apparatus, oculomotor nerve, cavernous sinus and the branches and perforators of the ICA (49,64-66). The operation necessitates a standard Yasargil pterional approach, followed by removal of the anterior clinoid process. This includes dissection of the distal dural ring and opening of the falciform ligament to adequately expose the proximal ICA, the aneurysm origin, and the OphA (64,65). Manipulation of the ON should be minimized to avoid visual deficits, with retraction maneuvers directed downward toward the ICA rather than upward toward the ON (64).

Despite these technical complexities, unruptured ophthalmic aneurysm can be treated safely and effectively by experienced neurosurgeons in specialized tertiary care centers (6). Microsurgical clipping may be considered in patients where antiplatelet therapy poses a high bleeding risk or in whom compliance to such therapy is uncertain (8). However, clipping is generally not recommended for older patients with significant major comorbidities who may not tolerate a complex open surgical procedure (6,49,65). It is also less suitable for patients with thrombosed and calcified ophthalmic aneurysm, large frontal sinuses, or a pneumatized optic strut, as these conditions increased the risk of complications during microsurgical clipping (6,65).

Appropriate clipping technique and clip selection conforming to the normal curvature of the ICA is critical to achieving optimal outcomes. For small ophthalmic aneurysms, a single clipping using simple curved or straight clip is usually sufficient. Large and/or broad-based ophthalmic aneurysms typically required multiple clipping, especially tandem clipping and stacked clipping (64). In case of very complex or giant ophthalmic aneurysm, an extracranial-intracranial bypass followed by microsurgical clipping or trapping may be performed (65,66). Alternatively, Seferi et al. proposed that, in selected cases, giant ophthalmic aneurysms may be safely clipped via a contralateral interoptic corridor. Suitable criteria for this approach include a small, non-calcified neck, dome projection between 11 and 1 o’clock on the coronal plane, and a non-prefixed optic chiasm (66).

The occlusion rate for microsurgical treatment of ophthalmic aneurysms varies across studies. In a large series of 114 unruptured ophthalmic aneurysm, Catapano et al. reported a complete occlusion of 85%, with a mean follow-up of 5.4 months (6). Kamide et al. demonstrated a higher complete occlusion rate of 93,3% despite treating larger aneurysm (64). In contrast, Lu et al. reported incomplete occlusion rates of 21.4% immediately postoperatively and 24.4% at early follow-up (6–12 months) (65).

Microsurgical complications and clinical outcomes

Reported rates of good clinical outcomes (mRS 0–2) for clipping range from 97% to 99.6% (6,49,65). However, single-arm analyses suggest that post-treatment visual deterioration and severe complications are more frequently observed in the microsurgical clipping group than in the endovascular group (7). Lu et al. found that significant independent risk factors for clipping ophthalmic aneurysms included age over 60 years and aneurysm size greater than 10 mm, both of which were associated with poorer outcomes (49).

Visual deficit is the most common postoperative complication following clamping of ophthalmic aneurysms, which also carries risks of stroke and intraoperative rupture. Reported rates of post-treatment visual morbidity range from 10.6% to 28.5% (7,49,64,65,67,68) and several studies reported that incidence of new visual deficits is significantly higher in patients undergoing microsurgical procedures compared to those treated with endovascular procedures (6,7,49). These deficits may include decreased visual acuity, visual field defect (such as hemianopsia or quadrantanopia), and monocular blindness. Kamide et al. analyzed 208 ophthalmic aneurysms treated by microsurgical clipping and reported decreased visual acuity in 2.4% of patients, visual field defect in 3.8%, and monocular blindness in 4.3% (67). Some authors reported that the most important causes of ON injury include heat injury during optic canal drilling and the inadvertent trapping of perforators in the aneurysm clips during clip application (64,67). Other possible mechanisms include manipulation of the ON during dissection from the aneurysm and direct compression of the ON by the applied clip (68,69). Therefore, meticulous microsurgical technique is essential during anterior clinoidectomy, aneurysm dissection, and clip application to preserve ON function and optimize visual outcomes.

Other severe complications included intracranial hematoma and ischemic cerebrovascular accident. In a large cohort of 247 patients with ophthalmic aneurysms, Catapano et al. observed a hematoma rate of 1.6%, which was associated an mRS score >2 (6). The incidence of severe neurological deficits resulting from an ischemic cerebrovascular accident has been reported to range between 0.4% and 1.6% (6,64).

Strengths and limitations

This is a narrative review focused specifically on the management of unruptured ophthalmic aneurysms. It provides a detailed and up-to-date summary of the current literature, incorporating findings from large case series and expert consensus published between 2014 and 2025. However, the strength of its conclusions is limited by quality of the available evidence. Most of the cited studies are retrospective, observational, or based on expert opinion, and randomized controlled trials are lacking. The exclusion of non-English language studies may also have reduced the breadth of the evidence base, potentially omitting valuable data from high-volume international centers. Furthermore, outcome reporting across studies is inconsistent, with variable definitions for occlusion, complication rates, and visual outcomes, limiting direct comparability. Standardized definitions and reporting frameworks are needed to facilitate more robust comparisons across treatment modalities.

Integrative perspective on clinical application

Management of unruptured ophthalmic aneurysms should be individualized, guided by aneurysm characteristics, symptoms, and patient background. Observation with imaging follow-up is generally appropriate for small, regularly shaped aneurysms in patients without high-risk factors (age <50 years, hypertension, Japanese ethnicity, prior SAH, or documented growth). Endovascular coiling, including balloon- or stent-assisted approaches, remains a valuable option for small-to-medium aneurysms with wide neck, when durable occlusion can be achieved without parent vessel reconstruction. FDS are effective for medium and large wide-neck or morphologically complex aneurysms, offering high occlusion rates and low recurrence. Their use requires 3–6 months DAPT, making them less suitable for patients at bleeding risk or those requiring future surgery. Intrasaccular flow disruptors are emerging as a promising option for small-to-intermediate wide-neck aneurysms, particularly in patients with contraindications to antiplatelet therapy. Microsurgical clipping remains an important option in selected cases—for example, in younger patients with low surgical risk, when mass effect necessitates urgent decompression, or when antiplatelet therapy is contraindicated—but it is associated with higher visual morbidity compared with endovascular options. In the absence of standardized guidelines, this comparative framework highlights how treatment indications vary according to aneurysm size, morphology, symptoms, and patient-specific considerations, as illustrated in Figure 1, and may assist clinicians in tailoring management to the individual patient.

Figure 1 Decision-making framework for unruptured ophthalmic aneurysms. DAPT, dual antiplatelet therapy.

Conclusions

Unruptured ophthalmic aneurysms are typically slow growing with a low rupture risk. Observation is appropriate for small, asymptomatic, regularly shaped aneurysms without high-risk features, while intervention is indicated for symptomatic, enlarging, or morphologically complex aneurysms. Endovascular techniques—particularly FDS—have become the preferred treatment due to high efficacy and favorable safety profiles. SAC and BAC are effective for wide-neck lesions, and emerging intrasaccular devices offer potential benefits without long-term antiplatelet therapy. Microsurgical clipping remains a viable option in selected cases but carries a higher risk of visual complications. In specialized tertiary care centers, management should be individualized through multidisciplinary evaluation, as no standardized guidelines currently exist. Future research should focus on multicenter prospective registries, standardized definitions of angiographic and clinical outcomes, and uniform follow-up protocols. These steps are essential to improve comparability and guide evidence-based management.

Acknowledgments

None.

Footnote

Provenance and Peer Review: This article was commissioned by the editorial office, Journal of Neurointervention for the series “Intracranial Aneurysms Current Status and Future Prospects”. The article has undergone external peer review.

Reporting Checklist: The authors have completed the Narrative Review reporting checklist. Available at https://jni.amegroups.com/article/view/10.21037/jni-25-36/rc

Peer Review File: Available at https://jni.amegroups.com/article/view/10.21037/jni-25-36/prf

Funding: None.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jni.amegroups.com/article/view/10.21037/jni-25-36/coif). The series “Intracranial Aneurysms Current Status and Future Prospects” was commissioned by the editorial office without any funding or sponsorship. J.L. and T.P. served as the unpaid guest editors of the series. T.P. serves as an unpaid editorial board member of Journal of Neurointervention from November 2024 to December 2026. J.L. reports honoraria for lectures from Medtronic, Acandis, and travel support from Acandis. N.K. reports teaching and training with Medtronic, Stryker, Penumbra and Microvention. T.B. received consulting fees from Medtronic and Siemens Healthineers. The authors have no other conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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