The authors aimed to evaluate the role of open cerebrovascular microsurgery for management of failed endovascular therapies for intracranial aneurysms in the modern neurointerventional surgery era. To identify patients who underwent open cerebrovascular surgery on brain aneurysms previously treated with endovascular interventions, the medical records of 476 patients who underwent endovascular treatment of intracranial aneurysms at the Brigham and Women's Hospital between 2018 and 2025 were reviewed and analyzed. Clinical, demographic, radiological, and surgical data were collected. The main outcomes included radiographic occlusion rates, complications, neurological functioning at the latest follow-up, morbidity, and mortality. Twenty-one patients (mean age 54.6 years; 57.1% females) underwent microsurgical treatment following endovascular therapy for intracranial aneurysms. Seventeen aneurysms (81.0%) were initially ruptured. Most aneurysms were located at the anterior communicating artery (33.3%) and posterior communicating artery (19.0%). Prior endovascular modalities included coil embolization only (14 cases), stent-assisted coiling (2 cases), intrasaccular devices (3 cases), flow diversion (1 case), and flow diversion following stent-assisted coiling (1 case). The mean duration between endovascular treatment and open surgery was approximately 37.8 months. Indications for subsequent open surgery included aneurysm residual or recurrence (n = 14), incomplete (n = 2) or failed (n = 2) endovascular treatment, rerupture after endovascular treatment (n = 2), and progressive growth with edema and brainstem compression (n = 1). Microsurgical techniques included clip reconstruction, with the use of bypass techniques in 4 cases. Complete aneurysm occlusion was achieved in all cases based on postoperative imaging, except for 2 patients who required aneurysm clip repositioning directly after surgery. One patient needed coil embolization because of aneurysm recurrence after clip reconstruction. Complications occurred in 6 patients (29%), with death in 2 patients (9.5%). At the last follow-up (mean 21.0 months), 81.0% of patients had a modified Rankin Scale score less than or equal to 2. Brain aneurysms can be safely managed by endovascular therapy in many cases, but case selection should be tailored to the specific patient anatomy on a case-by-case basis. There remains a significant role for open surgical management of brain aneurysms after failed endovascular therapy, and these cases are increasingly complex and difficult to treat.

Standalone short-coil embolization of the middle meningeal artery for subdural hematomas: Efficient, safe, and radiation-sparing.

Does embryologic basilar fusion type impact basilar apex aneurysm treatment outcomes?

Rationale:The purpose of this case report is to describe the process of oculomotor nerve palsy (ONP) in a patient after interventional treatment of anterior communicating artery aneurysms, so as to remind clinicians to pay attention to the condition of ONP in such patients.Patient concerns:A 73-year-old female patient was admitted with spontaneous vomiting for 4 days and had a Glasgow coma score score of 12 after admission. Three hours after admission, the Glasgow coma score score decreased to 5, and subsequent lumbar puncture drainage revealed bloody CSF.Diagnoses:Cerebral angiography confirmed the presence of 2 anterior communicating aneurysms.Interventions:Stent-assisted coil embolization (stent model: LVIS3.5–17, coil model: APB-1.5-3-3D, APB-1-2-3D, APB-1-1-HX) was performed. A stent was placed in the A2 segment of the anterior cerebral artery, and the aneurysm was completely embolized by stent-assisted release of 3 coils.Outcomes:The patient developed persistent unilateral ONP after surgery and was not followed up because the family requested discharge.Lessons:Anterior communicating artery aneurysms are often mistakenly thought not to cause ONP due to their anatomical relationship. Our case confirms that in rare cases, ACOA aneurysm can also cause ONP, which reminds clinicians that they should think more comprehensively when patients present with ONP.

Intracranial aneurysms (IAs) are weakened brain blood vessels at risk of rupture, often leading to subarachnoid hemorrhage, a condition with approximately 44% mortality (Bugazia et al., 2024). Endovascular coil embolization, which induces clot formation within the aneurysm sac, is a common intervention. However, it often faces complications. Inflammation is critical in this healing process, with neutrophils playing a key role by releasing enzymes to clear damaged tissue. However, excessive neutrophil activity can weaken the aneurysm wall and hinder complete healing (Rosales, 2018). This study investigates the effects of neutrophil depletion and granulocyte-colony stimulating factor (G-CSF) inhibition on aneurysm healing using the murine aneurysm model. Elastase-induced aneurysm was created and then an endovascular coil was placed in the carotid artery of mice to mimic the effects of endovascular coiling. Mice received an anti-PNM antibody to deplete neutrophils or an anti-G-CSF antibody to inhibit neutrophil activation. Anti-PMN was administered 7 days before coiling and every other day until day 21; anti-G-CSF was given 2 days before coiling, on the day of, and every other day thereafter. To assess the effects of these interventions, we measured tissue ingrowth into the aneurysm and conducted cytokine arrays for 144 different cytokines. Results showed a trend toward improved tissue ingrowth in the anti-PMN group (p = 0.06) and significant improvement in the anti-G-CSF group (p = 0.04). The cytokine array results revealed significant elevations in G-CSF, RANTES, and IL-17F, with G-CSF showing the most substantial increase due to its crucial role in recruiting neutrophils and modulating inflammation. These findings suggest potential cell-targeted treatments for intracranial aneurysms.

Introduction: Left main coronary artery (LMCA) aneurysms are exceedingly rare, accounting for only 0.1% of all coronary anomalies. Their detection is often missed on conventional ischemia evaluation. This case illustrates how coronary CT angiography (CTA) can identify complex coronary pathology, including aneurysms and mechanical compression of adjacent vessels. Large LMCA aneurysms pose significant clinical challenges due to their potential for thromboembolism, rupture, and compression of adjacent coronary vessels. Early identification through advanced imaging modalities is crucial for optimal patient outcomes and procedural planning. Description of Case: A 78-year female with a history of hypertension, hyperlipidemia, HIV, and rheumatoid arthritis presented with atypical chest pain. Coronary CTA was performed, revealing an incidental calcified saccular aneurysm, with a size of 33.9 x 33.4 mm, arising from the distal LMCA with intra-aneurysmal calcifications and thrombus (Figure 1). The aneurysm caused mild luminal compression of the proximal LAD (p-LAD). Coronary arteries were non-obstructive. Invasive coronary angiogram was done and the patient underwent coiling embolization to exclude the aneurysm with no periprocedural complications (Figure 2). The patient tolerated the procedure and is planned to have both clinical and non-invasive imaging follow-up. In this patient, CTA enabled prompt diagnosis and guided further intervention. Discussion: This case illustrates coronary CTA's paradigmatic role transcending conventional ischemia-focused diagnostics. Contemporary evidence demonstrates CTA's superior anatomical characterization capabilities, enabling comprehensive assessment of complex coronary pathology including aneurysmal morphology, calcification burden, and spatial relationships with adjacent structures The three-dimensional reconstructive capacity facilitates precise procedural planning by quantifying aneurysm dimensions, determining optimal coil sizing, and predicting potential procedural complications. This case underscores CTA's evolving utility in guiding interventional decision-making for rare coronary anomalies, demonstrating enhanced diagnostic precision and therapeutic stratification beyond traditional functional assessment paradigms.

Case: A 23-year-old non-smoking male with no comorbidities or trauma history presented with one year of exertional dyspnea. Physical exam and initial workup (CXR, EKG, CBC, BMP, BNP, TrI, lipids, TPHA) were unremarkable. TTE revealed abnormal continuous flow into the RA with aneurysmal RCA origin (14mm); normal LVEF (63%) and PAPS. Color Doppler showed a significant shunt (5mm). Contrast-enhanced CCTA with 3D reconstructions confirmed an aneurysmal RCA ostium (10 mm) and proximal RCA (11 mm). The SNA originates from the RCA, with a 13mm SNA aneurysm and a 9 mm fistula draining into the RA. A contrast jet was visualized through the fistula. The patient underwent successful open surgical repair with direct intra-atrial closure of the fistulous orifice combined with external fistula ligation. Postoperative recovery was uneventful. Discussion: Coronary artery fistulas (CAFs) are rare, with a prevalence of 0.002% in general population, most often arising from the RCA (55%) or LAD (35%) and draining into low-pressure cardiac chambers. Rarest of all is the triad of RCA aneurysm, SNA aneurysm, and CAF to the RA. This has been reported in only two prior cases. Our patient is the youngest reported adult to present this. Clinical presentation varies with the size and hemodynamic impact of the CAF. 50% of patients are asymptomatic. Larger fistulas can cause dyspnea, palpitations, fatigue, and angina. ECG and CXR are often normal unless a large left-to-right shunt is present. TTE may show dilated coronary arteries, enlarged chambers, and turbulent flow. Contrast-enhanced CCTA with 3D reconstruction is crucial for precise anatomical delineation of both aneurysms and the fistulous tract, facilitating surgical planning. Our patient presented with minimal symptoms but significant lesions on imaging, emphasizing the importance of high clinical suspicion and comprehensive imaging. No formal guideline of CAF management exist. Small CAFs may close spontaneously with excellent prognosis. Larger ones can lead to complications (premature CAD, endocarditis, pulmonary hypertension, heart failure, rupture) and require closure, either percutaneously or surgically. Given the exertional dyspnea and large fistula, surgical closure was indicated in this case. Coil embolization was not chosen due to the complexity of the lesion. Resection of the aneurysm was deferred due to its size, absence of mass effect, and the importance of preserving SNA flow to maintain sinoatrial node function.

Introduction: Foreign body migration into cardiac chambers is a rare but potentially life-threatening complication of vascular interventions such as gonadal vein embolization. Migration of coils into the right atrium (RA) may lead to thromboembolism, valvular injury, arrhythmias, or perforation. Prompt recognition and retrieval are essential to avoid complications. Research Question: Can a percutaneous approach safely and effectively retrieve a migrated embolization coil from the right atrium in a stable young adult? What technical considerations and device strategies increase success in such complex retrievals? Goals/Aims: To describe a challenging case of right atrial embolization coil retrieval using advanced endovascular techniques and to highlight the importance of individualized procedural planning in high-risk patients. Case Presentation: A 27-year-old female presented with pleuritic chest pain, dizziness, and a history of prior gonadal vein embolization. Imaging revealed a metallic foreign body in the right atrium. Transthoracic echocardiography (TTE) and CT confirmed coil presence (2.25 × 1.25 cm) affixed to the RA roof. Multidisciplinary decision-making favored a percutaneous approach. Preprocedural TEE was performed for localization. Retrieval attempts included use of multi-loop snares, J-wire looping, balloon trapping (Cordis balloon), and ultimately AngioVac aspiration with ECMO backup. An Amplatz Super Stiff wire facilitated device support. Management/Outcome: Initial snare attempts led to fraying and partial coil removal. Sequential strategies including balloon trapping via right internal jugular access and mechanical aspiration with AngioVac were employed. A 7 × 20 mm balloon was inflated within the AngioVac sheath at 23 atm to trap the coil. Successful en bloc removal was achieved under fluoroscopy and confirmed by intraoperative TEE. The patient remained hemodynamically stable and was discharged the following day without complications. Conclusion: Percutaneous retrieval of migrated intravascular coils can be successful with advanced planning and a stepwise escalation of techniques. Success hinges on detailed imaging, anatomical understanding, and availability of equipment such as snares, balloons, and vacuum-assisted retrieval systems. While percutaneous removal is preferred, procedural flexibility and surgical backup are critical in complex cases.

Background: Coronary artery fistulae (CAF) are rare anomalies, found in approximately 0.05- 0.2% of the population. Fistulous connections draining into the pulmonary artery represent an uncommon subset, usually clinically silent but occasionally symptomatic due to coronary steal. Case: A 51-year-old man with hyperlipidemia presented with a 1-month history of exertional chest pain. Baseline transthoracic echocardiography revealed normal biventricular size and function. Exercise ECG stress testing elicited chest tightness at peak exertion (14.8 METs) and showed 1.5 mm horizontal ST-segment depression in leads V4- V6. Coronary angiography via right radial artery showed revealed no obstructive coronary artery disease but identified a myocardial bridge in the mid left anterior descending (LAD) artery and bilateral coronary artery fistulae. Both fistulae were Sakakibara Type-A, originating from the proximal LAD and right coronary artery (RCA), and draining into the main pulmonary artery. Coronary CT angiography confirmed two simple, small-caliber fistulae: one from the first septal branch of the LAD and another from the conus branch of the RCA. Decision Making: The patient’s symptoms were attributed to a combination of dynamic compression from the LAD myocardial bridge and coronary steal from bilateral CAFs. Due to the small size and simple morphology of the fistulae, initial management was conservative, using beta-blockers to reduce myocardial oxygen demand. Invasive options such as transcatheter coil embolization or surgical correction are reserved for cases with progressive symptoms, significant shunting, or pulmonary artery dilation. Conclusion: Coronary to pulmonary artery fistulae, though rare, should be considered in patients with ischemic symptoms and 'normal' coronary arteries. Detailed anatomical assessment with invasive coronary angiography and cardiac CT angiography is essential for diagnosis and risk stratification. Management should be individualized based on symptom burden and fistula anatomy.

De novo aneurysm formation at the anastomotic site of superficial temporal artery (STA)-middle cerebral artery (MCA) bypass surgery for moyamoya disease (MMD) is an exceptionally rare but clinically significant complication. Previously reported cases were treated with direct microsurgery, where preservation of established pial synangiosis was a major concern. The authors herein report the first case successfully treated with endovascular coil embolization, achieving complete preservation of pial synangiosis and a favorable clinical outcome. A 53-year-old man had undergone combined revascularization surgery for MMD 14 years earlier. Although the patient remained asymptomatic, follow-up MR angiography revealed a gradually enlarging de novo aneurysm with daughter sac formation at the anastomotic site. Cerebral angiography demonstrated a narrow-neck saccular aneurysm and a well-developed donor STA, allowing access for endovascular treatment. A microcatheter was advanced into the aneurysm via a distal access catheter placed in the STA, and coil embolization with five coils achieved complete obliteration. The patient recovered uneventfully, and follow-up imaging confirmed the durable occlusion. Endovascular therapy represents a valuable treatment option for de novo aneurysm after STA-MCA anastomosis in MMD, as it completely preserves established collaterals. Careful patient selection and meticulous procedural planning are essential to ensure safety and efficacy. https://thejns.org/doi/10.3171/CASE25666.

Aneurysms of the fetal-type posterior cerebral artery (FPCA) are rare and often present with fusiform or dissecting morphology. Unlike the adult-type posterior cerebral artery (PCA), the FPCA can only be accessed through the internal carotid artery, limiting endovascular routes and device options. These anatomical and technical constraints often necessitate parent artery occlusion (PAO) as a treatment strategy; however, it carries a substantial risk of ischemic complications. The authors report a rare case of a ruptured FPCA aneurysm with ipsilateral P1 segment aplasia, treated successfully with stent-assisted coil embolization with preservation of anterograde FPCA flow. A 79-year-old woman presented with subarachnoid hemorrhage and impaired consciousness. Imaging revealed a fusiform aneurysm along the FPCA and aplasia of the ipsilateral P1 segment. Because of narrow vessel anatomy, dual microcatheter techniques were not feasible. After conservative management, the patient underwent stent-assisted coil embolization via a transcellular approach. The aneurysm was completely obliterated with preserved FPCA flow, and no ischemic complications occurred. A literature review suggests that aneurysms with saccular configuration and proximity to the P2 segment are favorable for selective coil embolization. Given the high risk of thalamic and occipital infarction associated with PAO, preserving FPCA flow should be prioritized when anatomically and technically feasible. https://thejns.org/doi/10.3171/CASE25556.

A 34‐year‐old female with atraumatic history presented with sudden‐onset headache and bilateral hand paresthesia. CT and CTA revealed a retroclival subdural hemorrhage. MRA showed a 6 mm right posterior communicating (PCom) artery aneurysm abutting the dura. The patient was treated with coil embolization and recovered in the ICU. This rare presentation of aneurysmal rupture into the subdural space highlights the need to consider aneurysmal causes in atraumatic subdural hematoma to prevent future catastrophic rebleeding. image image

Introduction Internal carotid artery (ICA) bifurcation aneurysms are a rare subtype of intracranial aneurysms with distinct hemodynamic characteristics and treatment challenges. This study aims to evaluate clinical outcomes associated with different endovascular approaches for ICA bifurcation aneurysms through a systematic review and meta‐analysis. Method A comprehensive literature search through PubMed and Scopus from January 2000 to July 2025. Data on patient demographics, aneurysm characteristics, and outcomes of coil embolization, stent‐assisted coiling, and flow diversion were extracted. Pooled analyses and subgroup comparisons were performed following PRISMA guidelines. Results Among 322 patients from 17 studies, primary coiling was most common (59.0%), followed by stent‐assisted coiling (30.1%) and flow diversion (10.2%). Endovascular treatment generally had good outcomes, with 74.5% achieving mRS 0‐2 and 72.4% complete occlusion. Recurrence was 13.0%, stroke occurred in 5.9%, and mortality was 2.8%. Stent‐assisted coiling had the best functional outcomes (97.7%) and high occlusion (75.3%) with low recurrence (8.1%) and no rebleeding. Primary coiling, while slightly less effective, had the best safety profile with stroke at 4.3% and mortality 2.7%. Flow diversion, used in complex cases, had higher risks, with stroke in 13.1% and mortality in 18.1%. Compared to flow diversion, primary coiling significantly lowered stroke (OR = 0.193, p = 0.009) and death (OR = 0.234, p = 0.036). No significant differences were found between stent‐assisted coiling and other methods, though trends favored it for efficacy. Conclusion Endovascular strategies for ICA bifurcation aneurysms are generally effective, with stent‐assisted coiling demonstrating favorable clinical and radiographic outcomes. Primary coiling embolization appears to offer the best safety profile, while flow diversion may carry higher procedural risks. Treatment selection should consider individual anatomical and clinical factors. image image

First-in-Human Ringer™ Balloon-Assisted Coil Embolization of Large Saphenous Vein Graft Aneurysm Using the Ping-Pong Technique.

Introduction Endovascular coil embolization has been effective for cerebral aneurysms since its inception; however, compared with surgical clipping, recanalization remains a concern after coiling. Significant recanalization often necessitates retreatment by re‐coiling or clipping. Established predictors include large/giant size, wide neck, ruptured status, and partial thrombosis. Migration or compaction of coils into intraluminal thrombus can further promote delayed recanalization. Purpose To present a case of recanalization of a partially thrombosed giant ACOM aneurysm after coiling. Methods Patient was encountered during routine clinical practice. Results A 64‐year‐old right‐handed man, heavy smoker and alcohol user with hypertension, presented with new‐onset generalized tonic‐clonic seizure. Brain MRI/MRA demonstrated a giant (3.5 × 2.4 × 3.0 cm) Anterior communicating (ACOM) artery aneurysm with substantial neck filling (17 × 8 × 6 mm) and partial thrombosis. The patient underwent stent‐assisted coil embolization of the aneurysm. At 6‐month follow‐up, diagnostic angiography revealed neck recanalization attributed to flow‐related coil migration into the partially thrombosed sac. He subsequently underwent additional embolization with a Pipeline Flex flow‐diverting stent. Conclusion Patients should be followed by a neurointerventional specialist after coiling to enable early detection of complications. Recanalization should be anticipated in giant, wide‐necked, ruptured, or partially thrombosed aneurysms. Complex intra‐aneurysmal flow and coil migration into mural thrombus can drive recurrence; in such settings, definitive flow diversion may be required at recurrence or considered in initial planning. image

Background Post‐tonsillectomy hemorrhage is among the most severe complications of this frequently performed surgery. While most bleeding occurs within the first week, delayed hemorrhage due to vascular injury or pseudoaneurysm formation is rare but potentially fatal. While most cases are managed conservatively or with operative cauterization, recurrent or massive hemorrhage may necessitate advanced interventions. Neuroendovascular techniques allow for selective arterial embolization which is critical for achieving hemostasis when conventional methods fail. Case Presentation We report a 13‐year‐old boy with trisomy 21 who developed life‐threatening oropharyngeal hemorrhage 14 days after tonsillectomy and adenoidectomy for obstructive sleep apnea. Initial surgical cauterization failed to achieve hemostasis. Diagnostic cerebral angiography revealed a pseudoaneurysm of the right deep lingual artery, which was treated with coil embolization. Six days later, recurrent hemorrhage prompted requiring repeat angiography. Removal of intraoperative airway packing enabled precise localization of the bleeding site, leading to successful embolization of the proximal right lingual artery. The patient subsequently recovered without further bleeding. Discussion Delayed post‐tonsillectomy hemorrhage, although uncommon, can be life‐threatening. This case highlights the role of early angiographic evaluation and endovascular therapy when surgical control fails. It also underscores how airway packing may obscure the bleeding source and its removal may improve diagnostic accuracy for vessel pathology. Conclusion Lingual artery pseudoaneurysm should be considered in delayed cases of severe or recurrent post‐tonsillectomy hemorrhage. Endovascular embolization offers a minimally invasive, effective treatment for achieving definitive hemostasis when surgical control is inadequate.

Introduction Cerebral vasospasm is a well‐recognized complication of aneurysmal subarachnoid hemorrhage and has been described with blood transfusion 1‐3 . In contrast, vasospasm after embolization of unruptured aneurysms, to our knowledge. has not been reported 4,5 . Materials/Methods Case report and literature review. Results A 49‐year‐old African American woman with a history of hypertension, iron‐deficiency anemia, and smoking presented with a week of headaches and binocular diplopia. Examination revealed an incomplete right oculomotor nerve palsy with pupillary involvement. Computed tomographic angiography (CTA) demonstrated a 5×5‐mm unruptured saccular aneurysm of the right posterior communicating artery. She underwent urgent coil embolization without procedural complications. On the first postoperative day, her headache had resolved, and her neurologic examination was unchanged. Transcranial Doppler ultrasonography (TCD) at 8 AM showed no evidence of vasospasm. Laboratory studies revealed a hemoglobin level of 6.5 g/dL, and she received one unit of packed red blood cells. Approximately one hour into transfusion, at 10 AM, she developed right gaze deviation and left hemiplegia. Non‐contrast CT excluded intracranial hemorrhage. CTA revealed severe vasospasm of the right middle cerebral artery (MCA), and CT perfusion showed a mismatch in the corresponding territory, consistent with ischemia. She was treated with intravenous fluids and underwent digital subtraction angiography (DSA), which confirmed delayed MCA filling. Intra‐arterial verapamil (27 mg) and nitroglycerin (40 μg) produced modest angiographic improvement. She was able to lift her arm antigravity immediately post procedure. Figure 1 depicts CTA and DSA before (panels A and C) and after (panels B and D) neurologic deficit during blood transfusion. Vasospasm is clearly evidenced. Lumbar puncture performed the following day revealed no xanthochromia. Her left hemiparesis resolved within 48 hours and her right oculomotor nerve palsy improved. Serial TCD studies showed no further vasospasm, and hemoglobin levels remained stable. She was discharged home after seven days. Conclusion This case illustrates transfusion‐associated vasospasm after coil embolization of an unruptured intracranial aneurysm. Although delayed cerebral ischemia due to vasospasm is a well‐known sequela of subarachnoid hemorrhage, its occurrence in unruptured aneurysms has not been reported. Transfusion has been implicated in vasospasm pathophysiology, possibly through reduced bioavailability of nitric oxide within stored erythrocytes 1 . Recognition of this association is important, as prompt diagnosis and treatment may mitigate ischemic injury. We conclude that transfusion‐induced vasospasm should be considered in the differential diagnosis of acute neurologic decline after coil embolization of unruptured aneurysms. image

ABSTRACTBronchial artery‐pulmonary artery fistula (BPAF) is an uncommon vascular malformation with a left‐to‐right shunt. We report a case of a 72‐year‐old woman diagnosed with BPAF with two arterial feeders who had no underlying lung diseases and presented with intermittent haemoptysis. Her digital subtraction angiography confirmed BPAF supplied by the right bronchial artery (BA) from the intercostobronchial trunk and another ectopic accessory right BA originating from the right subclavian artery. Considering the future risk of catastrophic rupture due to high systemic pressure exerted on the fistula, prophylactic embolisation procedures via a percutaneous approach were performed. The pulmonary artery was first embolised for outflow control, followed by coil and microvascular plug embolisation on the right BA. The ectopic accessory right BA was later embolised with coil and microvascular plug as a staged procedure. A 14‐month post‐procedure computed tomography scan confirmed complete thrombosis of both BAs. Our case highlights the efficacy and safety of endovascular embolisation in BPAF.

Radial-first to wrist-first: Transulnar arterial access for diagnostic cerebral angiography and neurovascular intervention.

Introduction Unruptured intracranial aneurysms occur in ∼2%‐3% of the general population and may be more prevalent in older adults, women, and those with relevant familial/genetic backgrounds. Internal carotid‐posterior communicating artery (ICA‐PCOM) aneurysms are a classic cause of oculomotor nerve compression. While many present with subarachnoid hemorrhage, they can also present with non‐traumatic subdural hematoma or isolated oculomotor palsy. Preoperative asymptomatic cases are uncommon; “splitting” of the oculomotor nerve by an aneurysm has been described intraoperatively as a mechanism of neuropathy. Purpose To present a case of an asymptomatic, pupil‐sparing large ICA‐PCOM aneurysm incidentally detected on cervical spine MRI. Materials and Methods The patient was identified in routine clinical practice. Results A 60‐year‐old woman with diabetes, asthma, hyperlipidemia, systemic lupus erythematosus, migraine, and anxiety presented with unsteadiness, memory concerns, and right‐sided neck pain radiating to the arm with intermittent numbness and subjective weakness. Neurologic exam showed decreased light touch over the right shoulder region, brisk deep tendon reflexes (3+) in both upper and lower limbs, and bilateral positive Hoffmann signs. Pupils were equal and reactive with no ptosis, diplopia, or other oculomotor deficit (pupil‐sparing). Cervical spine MRI obtained for radiculopathy revealed an ovoid T2 hypointensity in the left suprasellar cistern suspicious for a large internal carotid artery aneurysm (∼15 mm). The study also showed a C3‐4 broad‐based disc‐osteophyte complex, left‐predominant, mildly deforming the ventral cord. Diagnostic cerebral angiography confirmed a large, bi‐lobulated, wide‐neck left ICA‐PCOM aneurysm measuring 15.4 × 13.6 × 13.5 mm. The aneurysm was treated with endovascular coil embolization; the immediate post‐procedure course was uncomplicated, and the patient remained without oculomotor deficits. Conclusion Asymptomatic, incidentally discovered ICA‐PCOM aneurysms can occur despite absent pupillary involvement. Vigilant review of suprasellar structures on non‐targeted studies such as cervical MRI can uncover actionable pathology. Endovascular coiling is a feasible treatment option for large, wide‐neck ICA‐PCOM aneurysms identified in this context. image