Chronic Oculomotor Nerve Palsy Presentation From Posterior Communicating Artery Aneurysm

Operative Neurosurgery 30:703–710, 2026

This case series analyzes 17 patients with subacute to chronic oculomotor nerve palsy (ONP) caused by posterior communicating artery (PCoA) aneurysms treated between 1991 and 2024. Demographics, aneurysm characteristics, treatment modalities (clipping vs endovascular), and follow-up outcomes are reported, highlighting that only a minority presented with rupture.

The report finds that complete ONP recovery occurred exclusively in patients treated within five weeks of symptom onset, supporting early definitive management to maximize functional nerve recovery despite chronic ONP not reliably predicting imminent aneurysm rupture.

Clinical question: The natural history of chronic oculomotor nerve palsy (ONP) from posterior communicating artery (PCoA) aneurysm is unclear, especially regarding rupture risk and likelihood of nerve recovery when symptoms persist beyond 1 week.

Cohort & design: Case series from a prospectively accrued institutional database (1991–2024) including patients with ≥1 week ONP attributed to PCoA aneurysm; patients with <1 week onset, inadequate follow-up, or other causes of ONP were excluded.

Patient profile: 17 patients; predominantly female (94.1%), median age 56; ONP duration ranged 1 week to 10 years; 29.4% presented with aneurysm rupture.

Treatment approaches: Most were treated with microsurgical clipping (64.7%) or endovascular therapy (29.4%); one patient was managed conservatively due to comorbidities/limited life expectancy.

ONP recovery outcomes: Complete ONP recovery occurred in 23.5% (4/17); all complete recoveries were in patients with symptom duration <5 weeks.

Timing signal: Subacute ONP (<5 weeks) was associated with better recovery (including complete recovery), while chronic ONP (≥5 weeks) had no complete recoveries in this cohort.

Rupture implication: Chronic ONP appeared not to indicate imminent rupture, with only about one-third presenting ruptured and an example of 10 years of stable ONP preceding rupture in the longest-duration case.

Management takeaway: Even if chronic ONP may not predict near-term rupture, early definitive aneurysm treatment is still recommended to maximize the chance of functional ONP recovery.

Oculomotor nerve palsy due to posterior communicating artery aneurysm: Clipping vs coiling

Neurochirurgie 68 (2022) 86–93 

Posterior communicating artery aneurysms (PCoAA) usually present with brain hemorrhage, but they might present with oculomotor nerve palsy (ONP) in about one out of five patients. Treatment options include endovascular coiling and surgical clipping. The present analysis aims to compare the two treatment options for ONP due to PCoAA in terms of complete recovery and related parameters.

Methods. – A comprehensive literature search was performed for studies published between 2000 and2019 on ONP due to PCoAA. The included studies were divided into two categories—surgical clipping (group A) and endovascular coiling (group B). The collected data were statistically processed with SPSSversion 25.

Results. – There was a significant difference between the two treatment groups regarding complete recovery of ONP (P < 0.001), suggesting superiority of the surgical clipping. The correlation analysis showed no correlations for group A. Group B had negative and positive correlations, showing that endovascular coiling results in higher rates of complete ONP recovery for elderly patients.

Conclusion. – Surgical clipping is superior to endovascular coiling in terms of complete recovery among patients with ONP due to PCoAAs. Endovascular coiling seems to benefit older patients. While no recommendations exist for the treatment of ONP due to intracranial aneurysms, an increasing number of studies imply the superiority of operative clipping

Recurrence and risk factors of posterior communicating artery aneurysms after endovascular treatment

Acta Neurochirurgica (2021) 163:2319–2326

Endovascular treatment (EVT) of posterior communicating artery aneurysms (PcomA) is challenging because of posterior communicating artery (Pcom) architecture. Additionally, these aneurysms have a high risk of recanalization compared with those located elsewhere.

Methods The radiographic findings of 171 patients treated with EVT at two institutions were retrospectively reviewed. Univariate and multivariate analyses were performed, and subgroup analyses were performed based on Pcom characteristics.

Results Recanalization of PcomAs occurred in 53 patients (30.9%). Seven patients (4.0%) were retreated (six endovascularly and one with microsurgical clipping). The mean follow-up duration was 27.7 months (range: 3.5–78.6). The maximum diameter (odds ratio [OR] 1.23, P = .006, 95% CI 1.07–1.44), a Raymond–Roy classification of grade II or III (OR 2.26, P = .03, 95% CI 1.08–4.82), and the presence of reinforcement (balloon or/and stent, OR 0.44, P = .03, 95% CI 0.20–0.91) were associated with recanalization using multivariate logistic regression. Significant differences were found in maximum aneurysm diameter (P = .03) between normal- and fetal-type Pcoms on analysis of variance.

Conclusions The recanalization rate of PcomAs after EVT was 30.9%; the retreatment rate was 4.0%. Maximum diameter, Raymond–Roy classification, and presence of reinforcement were significantly associated with recanalization but not associated with fetal-type Pcom. Aneurysm size was larger in patients with a fetal-type Pcom than in those with a normal Pcom. Pcom size was not related to recanalization rate.

Riskier-than-expected occlusive treatment of ruptured posterior communicating artery aneurysms

J Neurosurg 131:1269–1277, 2019

Occlusive treatment of posterior communicating artery (PCoA) aneurysms has been seen as a fairly uncomplicated procedure. The objective here was to determine the radiological and clinical outcome of patients after PCoA aneurysm rupture and treatment and to evaluate the risk factors for impaired outcome.

METHODS In a retrospective clinical follow-up study, data were collected from 620 consecutive patients who had been treated for ruptured PCoA aneurysms at a single center between 1980 and 2014. The follow-up was a minimum of 1 year after treatment or until death.

RESULTS Of the 620 patients, 83% were treated with microsurgical clipping, 8% with endovascular coiling, 2% with the two procedures combined, 1% with indirect surgical methods, and 6% with conservative methods. The most common procedural complications were treatment-related brain infarctions (15%). The occurrence of artery occlusions (10% microsurgical, 8% endovascular) was higher than expected. Most patients made a good recovery at 1 year after aneurysmal subarachnoid hemorrhage (modified Rankin Scale [mRS] score 0–2: 386 patients [62%]). A fairly small proportion of patients were left severely disabled (mRS score 4–5: 27 patients [4%]). Among all patients, 20% died during the 1st year. Independent risk factors for an unfavorable outcome, according to the multivariable analysis, were poor preoperative clinical condition, intracerebral or subdural hematoma due to aneurysm rupture, age over 65 years, artery occlusion on postoperative angiography, occlusive treatment–related ischemia, delayed cerebral vasospasm, and hydrocephalus requiring a shunt.

CONCLUSIONS Even though most patients made a good recovery after PCoA aneurysm rupture and treatment during the 1st year, the occlusive treatment–related complications were higher than expected and caused morbidity even among initially good-grade patients. Occlusive treatment of ruptured PCoA aneurysms seems to be a high-risk procedure, even in a high-volume neurovascular center.

Recovery from oculomotor nerve palsy due to posterior communicating artery aneurysms: results after clipping versus coiling in a single-center series

Recovery from oculomotor nerve palsy due to posterior communicating artery aneurysms- results after clipping versus coiling in a single-center series

Acta Neurochir (2014) 156:879–884

Oculomotor nerve palsy (ONP) is a common clinical manifestation of ruptured or unruptured posterior communicating artery (PcomA) aneurysms. Although microsurgical clip ligation has been proven a safe and durable treatment, endovascular management is emerging as an increasingly popular alternative. The aim of our study is to compare the recovery rate from ONP and assess the safety and long-term durability of both techniques.

Methods We have reviewed the retrospective data concerning twenty-two patients treated at our institution between 2004 and 2012 for PcomA aneurysms with ONP. Seven patients were operated on via a standard pterional approach, and fourteen were treated by endovascular occlusion with coils. One patient was managed conservatively. Pre-treatment and post-treatment severity of ONP was recorded, as well as the duration of symptoms before admission and treatment-related complications.

Results All seven patients who underwent surgery improved, with six total recoveries and one partial recovery. Among the fourteen patients treated by embolization, thirteen initially recovered, but long-term follow-up revealed three cases of exacerbation of ONP after refilling of the aneurysms. Two of them were clipped, and one embolized. Also, one partially resolved patient underwent a second embolization. No severe complications occurred in either group.

Conclusions Despite the small number of patients, our study suggests that both surgical clipping and embolization are safe and effective methods in regards to functional recovery (complete ONP recovery in about 85 % of the cases). However, coiling may lead to delayed recurrence of third cranial nerve (CN) palsy at long-term follow-up, requiring additional treatment. Keywords

Microsurgical Clipping of Posterior Communicating Artery Aneurysms in the Endovascular Era

Neurosurgery 71:285–295, 2012 DOI: 10.1227/NEU.0b013e318256c3eb

Many neurosurgeons feel competent clipping posterior communicating artery (PCoA) aneurysms and include this lesion in their practice. However, endovascular therapy removes simple aneurysms that would have been easiest to clip with the best results. What remains are aneurysms with complex anatomy and technical challenges that are not well described.

OBJECTIVE: A contemporary surgical series with PCoA aneurysms is reviewed to define the patients, microsurgical techniques, and outcomes in current practice. METHODS: A total of 218 patients had 218 PCoA aneurysms that were treated microsurgically during an 11-year period. Complexities influencing aneurysm management included (1) large/giant size; (2) fetal posterior cerebral artery; (3) previous coiling; (4) anterior clinoidectomy; (5) adherence of the anterior choroidal artery (AChA); (6) intraoperative aneurysm rupture; (7) complex clipping; and (8) atherosclerotic calcification.

RESULTS: Simple PCoA aneurysms were encountered in 113 patients (51.8%) and complex aneurysms in 105 (48.2%). Adherent AChA (13.8%) and intraoperative rupture (11.5%) were the most common complexities. Simple aneurysms had favorable outcomes in 86.6% of patients, whereas aneurysms with 1 or multiple complexities had favorable outcomes in 78.2% and 75.0%, respectively. Intraoperative rupture (P , .01), large/giant size (P = .04), and complex clipping (P = .05) were associated with increased neurological worsening.

CONCLUSION: Because endovascular therapy alters the surgical population, neurosurgeons should recalibrate their expectations with this once straightforward aneurysm. The current mix of PCoA aneurysms requires advanced techniques including clinoidectomy, AChA microdissection, complex clipping, and facility with intraoperative rupture. Microsurgery is recommended for recurrent aneurysms after coiling, complex branches, aneurysms causing oculomotor nerve palsy, multiple aneurysms, and patients with hematomas.