De novo aneurysm formation after the contralateral middle cerebral aneurysm clipping operation: a case report and review of literature

A left middle cerebral artery aneurysm was ruptured and clipped, but a de novo aneurysm on contralateral side ruptured within 5 years in a 38-year-old man. The cause of the formation of de novo aneurysms is unknown and is not consistent with most of current reports.

Epidemiology and outcomes of pediatric intracranial aneurysms: comparison with an adult population in a 30-year, prospective database

OBJECTIVE Pediatric intracranial aneurysms are rare. Most large series in the last 15 years reported on an average of only 39 patients. The authors sought to report their institutional experience with pediatric intracranial aneurysms from 1991 to 2021 and to compare pediatric patient and aneurysm characteristics with those of a contemporaneous adult cohort. METHODS Pediatric (≤ 18 years of age) and adult patients with one or more intracranial aneurysms were identified in a prospective database. Standard epidemiological features and outcomes of each pediatric patient were retrospectively recorded. These results were compared with those of adult aneurysm patients managed at a single institution over the same time period. RESULTS From a total of 4500 patients with 5150 intracranial aneurysms admitted over 30 years, there were 47 children with 53 aneurysms and 4453 adults with 5097 aneurysms; 53.2% of children and 36.4% of adults presented with a subarachnoid hemorrhage (SAH). Pediatric aneurysms were significantly more common in males, more likely giant (≥ 25 mm), and most frequently located in the middle cerebral artery. Overall, 85.1% of the pediatric patients had a modified Rankin Scale score ≤ 2 at the last follow-up (with a mean follow-up of 65.9 months), and the pediatric mortality rate was 10.6%; all 5 patients who died had an SAH. The recurrence rate of treated aneurysms was 6.7% (1/15) in the endovascular group but 0% (0/31) in the microsurgical group. No de novo aneurysms occurred in children (mean follow-up 5.5 years). CONCLUSIONS Pediatric intracranial aneurysms are significantly different from adult aneurysms in terms of sex, presentation, location, size, and outcomes. Future prospective studies will better characterize long-term aneurysm recurrence, rebleeds, and de novo aneurysm occurrences. The authors currently favor microsurgical over endovascular treatment for pediatric aneurysms.

Short- and midterm outcome of ruptured and unruptured intracerebral wide-necked aneurysms with microsurgical treatment

To clip or coil has been matter of debates for several years and is the domain of interdisciplinary decision making. However, the microsurgical outcome has still been elusive concerning wide neck aneurysms (WNA). A retrospective single center study was performed with all patients with ruptured WNA (rWNA) and unruptured WNA (uWNA) admitted to author´s institute between 2007–2017. Microsurgical outcome was evaluated according to Raymond-Roy occlusion grade and follow-up angiography was performed to analyze the stability of neck/aneurysm remnants and retreatment poverty. Of 805 aneurysms, 139 were rWNA (17.3%) and 148 uWNA (18.4%). Complete occlusion was achieved in 102 of 139 rWNA (73.4%) and 112 of 148 uWNA (75.6%). Neck remnants were observed in 36 patients with rWNA (25.9%) and 30 patients with uWNA (20.3%), 1 (0.7%) and 6 (4.1%) patients had aneurysmal remnant, respectively. Overall complication rate was 11.5%. At follow-up (939/1504 months), all remnants were stable except for one, which was further conservatively treated with marginal retreatment rate under 1%. Even the risk of de-novo aneurysm was higher than the risk for remnant growth (2.6% vs 0% in rWNA; 8.7% vs 5.3% in uWNA) without significant difference. Microsurgical clipping is effective for complete occlusion of r/uWNA with low complication. Furthermore, the risk of remnant growth is marginal even lower than the risk of de-novo rate low retreatment rate.

Is 3 years adequate for tracking completely occluded coiled aneurysms?

OBJECTIVEThe authors conducted a study to ascertain the long-term durability of coiled aneurysms completely occluded at 36 months’ follow-up given the potential for delayed recanalization.METHODSIn this retrospective review, the authors examined 299 patients with 339 aneurysms, all shown to be completely occluded at 36 months on follow-up images obtained between 2011 and 2013. Medical records and radiological data acquired during the extended monitoring period (mean 74.3 ± 22.5 months) were retrieved, and the authors analyzed the incidence of (including mean annual risk) and risk factors for delayed recanalization.RESULTSA total of 5 coiled aneurysms (1.5%) occluded completely at 36 months showed recanalization (0.46% per aneurysm-year) during the long-term surveillance period (1081.9 aneurysm-years), 2 surfacing within 60 months and 3 developing thereafter. Four showed minor recanalization, with only one instance of major recanalization. The latter involved the posterior communicating artery as an apparent de novo lesion, arising at the neck of a firmly coiled sac, and was unrelated to coil compaction or growth. Additional embolization was undertaken. In a multivariate analysis, a second embolization for a recurrent aneurysm (HR = 22.088, p = 0.003) independently correlated with delayed recanalization.CONCLUSIONSAlmost all coiled aneurysms (98.5%) showing complete occlusion at 36 months postembolization proved to be stable during extended observation. However, recurrent aneurysms were predisposed to delayed recanalization. Given the low probability yet seriousness of delayed recanalization and the possibility of de novo aneurysm formation, careful monitoring may be still considered in this setting but at less frequent intervals beyond 36 months.

Lack of impact of polycystic kidney disease on the outcome of aneurysmal subarachnoid hemorrhage: a matched case-control study

OBJECTIVEThe authors set out to study whether autosomal dominant polycystic kidney disease (ADPKD), an established risk factor for intracranial aneurysms (IAs), affects the acute course and long-term outcome of aneurysmal subarachnoid hemorrhage (aSAH).METHODSThe outcomes of 32 ADPKD patients with aSAH between 1980 and 2015 (median age 43 years; 50% women) were compared with 160 matched (age, sex, and year of aSAH) non-ADPKD aSAH patients in the prospectively collected Kuopio Intracranial Aneurysm Patient and Family Database.RESULTSAt 12 months, 75% of the aSAH patients with ADPKD versus 71% of the matched-control aSAH patients without ADPKD had good outcomes (Glasgow Outcome Scale score 4 or 5). There was no significant difference in condition at admission. Hypertension had been diagnosed before aSAH in 69% of the ADPKD patients versus 27% of controls (p < 0.001). Multiple IAs were present in 44% of patients in the ADPKD group versus 25% in the control group (p = 0.03). The most common sites of ruptured IAs were the anterior communicating artery (47% vs 29%, p = 0.05) and the middle cerebral artery bifurcation (28% vs 31%), and the median size was 6.0 mm versus 8.0 mm (p = 0.02). During the median follow-up of 11 years, a second aSAH occurred in 3 of 29 (10%) ADPKD patients and in 4 of 131 (3%) controls (p = 0.11). A fatal second aSAH due to a confirmed de novo aneurysm occurred in 2 (6%) of the ADPKD patients but in none of the controls (p = 0.027).CONCLUSIONSThe outcomes of ADPKD patients with aSAH did not differ significantly from those of matched non-ADPKD aSAH patients. ADPKD patients had an increased risk of second aSAH from a de novo aneurysm, warranting long-term angiographic follow-up.

Formation of intracranial de novo aneurysms and recurrence after neck clipping: a systematic review and meta-analysis

OBJECTIVEIncidence rates of de novo aneurysm formation and recurrence after clip ligation remain controversial. In this meta-analysis, the authors provide data on pooled annual incidence rates and the association of patient characteristics with time to formation of de novo aneurysms and time to recurrence after clipping.METHODSA search of the literature up to June 15, 2016, on PubMed and a systematic review were performed. The association of age, aneurysm rupture status, aneurysm multiplicity, and anatomical location with time to recurrence or formation of de novo aneurysm was estimated using multivariable Cox proportional-hazards models. Kaplan-Meier estimates (event-free survival curves) are shown. Pooled annualized incidence rates of recurrent and de novo aneurysms were estimated using Poisson regression. Proportions of aneurysms and average follow-up times are displayed as bubble plots with LOESS smoothers weighted for study size.RESULTSOf the 7606 articles screened, 92 were included in the study. Case reports on 101 patients with recurrent aneurysms and 132 patients with de novo aneurysms were analyzed. Long-term follow-up studies on de novo aneurysm formation included 13,723 patients with 101,378 patient-years of follow-up; studies on aneurysm recurrence included 5922 patients with 31,055 patient-years of follow-up. Mean time to recurrence was 12.9 ± 6.6 years (mean ± standard deviation), and mean time to de novo formation was 9.3 ± 6.1 years. No association with sex, aneurysm location, and initial rupture could be shown. De novo aneurysms occurred later in patients with multiplicity of aneurysms at diagnosis (HR 0.63, p = 0.03) and in patients with increasing age (HR per 10 yrs 0.88, p = 0.06). Pooled annualized incidence rates were 0.35% for de novo aneurysms and 0.13% for recurrent aneurysms.CONCLUSIONSDespite low reported annual incidence rates, the cumulative risk of 9.6%–22% for aneurysm recurrence or de novo formation 20 years after clip ligation warrants lifelong follow-up. Screening at 5, 10, and 20 years would detect 30.8% (95% CI 23.3%–37.6%), 64.2% (95% CI 55.9%–70.9%), and 95.9% (95% CI 90.9%–97.9%) of de novo aneurysms. Screening for recurrent aneurysms at 10, 15, and 20 years would detect 36.6% (95% CI 26.5%–45.4%), 65.3% (95% CI 54.7%–73.5%), and 95.1% (95% CI 85.8%–96.6%) of lesions.