Incidence and Case-Fatality of Aneurysmal Subarachnoid Hemorrhage in Australia, 2008-2018.

BACKGROUND: Contemporary aneurysmal subarachnoid hemorrhage (aSAH) and case-fatality studies have suggested a diminishing worldwide incidence. The purpose of this study was to examine whether such epidemiologic trends occur in Australia. METHODS: This retrospective cross-sectional study was based on data retrieved from the Nationwide Hospital Morbidity Database for all aSAH cases across hospital networks in Australia between 2008 and 2018. Information on patient characteristics, aneurysm location, procedures performed, and discharge disposition were extracted. We estimated the crude and age-adjusted incidences, trends of aSAH, and case fatality rate over time. Putative risk factors were investigated with univariate and multivariate logistic regression analysis to identify independent predictors of unfavorable discharge outcome (death and dependency). RESULTS: A total of 12,915 acute hospital admissions with aSAH were identified. Annual aSAH rate remained stable (mean 5.5, range 5.3-6.0 cases per 100,000 person-years) with no decline. The overall aSAH-associated 30-day case-fatality rate was 26.7% of admissions and declined by approximately 0.7% annually (P < 0.0001). Age-adjusted incidence increased with advancing age at increments of 1.3 cases per 100,000 person-years for each 5 years after the age of 40 years. Endovascular therapy accounted for 63.1% of the overall treatment strategy. Logistic regression demonstrated older age (P < 0.0001), presence of intracerebral or intraventricular hemorrhage (P < 0.0001), and hypertension (P = 0.0007) were significant predictors of unfavorable outcome. CONCLUSIONS: A decline in 30-day case-fatality rate but not aSAH incidence from 2008 to 2018 was observed.

Smoking increases the risk of de novo intracranial aneurysms.

OBJECTIVE: Case series have identified that de novo intracranial aneurysms occur. However, the risk for this occurrence has not been established. We examined the risk for the de novo intracranial aneurysm detection in a consecutive surgical case series. METHODS: A prospectively collected surgical database of intracranial aneurysms was retrospectively examined. Patients were analyzed if they were followed for more than 6 months postoperatively with angiography. Kaplan-Meier curve analysis of de novo aneurysms detection included the comparison of smoking vs. never smoked; those with and without a family history; single vs. multiple aneurysms at initial presentation; and original presentation with rupture vs. nonrupture. RESULTS: Of the 1366 surgically treated patients (1942 aneurysms), 472 patients (702 aneurysms) were followed with angiography for more than 6 months (average, 54 months). Thirty-three patients (6.99%) were detected to have de novo aneurysms. Multivariate analysis found a smoking history significantly increases the likelihood of de novo aneurysm detection. Kaplan-Meier analysis found the 5- and 10-year de novo aneurysm detection rate to be 4.21% (95% confidence interval [CI] 3.86-12.8) and 15% (95% CI 10-16), respectively. A smoking history increases the 5- and 10-year detection rate to 5.81% and 17% (hazard ratio 2.58; 95% CI 1.13-5.90) respectively. No increased risk was present for an initial presentation that included multiple aneurysms, a family history, or rupture. CONCLUSION: There is a 10-year de novo aneurysm detection rate of between 10% and 16% after surgery. Smoking increases the risk of de novo aneurysm detection. Consideration needs to be given to surveillance angiography after aneurysm treatment.

Use of indocyanine green videoangiography during intracranial aneurysm surgery reduces the incidence of postoperative ischaemic complications.

Microscope-integrated near-infrared indocyanine green videoangiography (ICGVA) has been shown to be a useful adjunct for intracranial aneurysm surgery. That the routine application of this technique reduces the risk of postoperative ischaemic complication, however, has not been reported. We present a retrospective matched-pair comparison of ICGVA guided aneurysm surgery versus historic control surgical cohort treated by the same author. Index patients and controls were matched for aneurysm size, location, patient demographics, risk factors, comorbidities, and surgical treatments. Ninety-one eligible patients with 100 intracranial aneurysms were treated using ICGVA assistance. There were no statistically significant differences between the two groups in terms of patient age, sex, risk factors, comorbidities and aneurysm characteristics. Of the 100 aneurysms in the ICGVA group, 107 investigations of ICGVA were performed. In 79 aneurysms (79.0%), ICGVA was considered useful but did not affect surgical management. In six patients (6.0%), ICGVA led to a crucial change of intraoperative strategies. In nine patients (9.0%), it was considered critical in assuring patency of small perforators. ICGVA was of no benefit in four patients (4.0%) and was misleading in two (2.0%). Postoperative ischaemic complications occurred in three patients (3.3%) in the ICGVA group compared with seven patients (7.7%) in the control group (p<0.001). Our study supports the use of ICGVA in aneurysm surgery as a safe and effective modality of intraoperative blood flow assessment. With all limitations of a retrospective matched-pair comparison, the use of ICGVA during routine aneurysm surgery reduces the incidence of postoperative ischaemic complications.

Outcomes for a case series of unruptured anterior communicating artery aneurysm surgery.

Surgical outcomes following repair of unruptured anterior communicating artery (AcomA) aneurysms have not been adequately addressed in the literature. We present our operative experiences in a consecutive series of 103 patients with 115 unruptured AcomA aneurysms. Clinical results, operative complications, angiographic outcomes and prognostic factors associated with surgery are presented. Of the 115 aneurysm repairs attempted, 114 were treated by clipping or excision and suture. One aneurysm, less than 2mm, was wrapped. Six patients (5.8%; 95% confidence interval [CI], 2.5-12.4) experienced a new permanent neurological deficit. There was no postoperative mortality. Transient morbidity occurred in 11 patients (10.7%; 95% CI, 5.9-18.3), including transient anosmia (four patients), acute postoperative confusion and memory disturbances (four patients), extradural haematoma requiring surgery (two patients) and cerebrospinal fluid rhinorrhea (one patient). Of the 84 aneurysms (73.0%) that had documented postoperative angiography, 82 (97.6%) had complete obliteration of the aneurysm and two (2.4%) had neck remnants (mean angiographic follow-up 28.0 months; range, 1.6-146.4 months). Retreatment was performed in one patient (1.0%). Logistic regression analysis of risk factors revealed that aneurysm size (p<0.01) was a significant predictor of outcome. There was no incidence of subarachnoid haemorrhage in the 272 person years of follow-up. In the current study, surgical treatment of unruptured AcomA aneurysms resulted in 5.8% morbidity and no mortality. The robustness of aneurysm repair achieved by open microsurgery is an important consideration when considering the option between endovascular and microsurgical treatment for unruptured AcomA aneurysms.

Outcomes for unruptured ophthalmic segment aneurysm surgery.

Ophthalmic segment aneurysms present unique technical challenges because of their proximity to the optic nerve and the anterior clinoid process. The current study was performed to examine whether surgery for unruptured ophthalmic segment aneurysms is an effective treatment modality with acceptable complication rates. A consecutive case series (prospectively collected data) was retrospective reviewed for the period between April 1992 and August 2012. Clinical results, operative complications, angiographic outcomes and prognostic factors associated with surgery are presented. Of the 169 patients with 182 unruptured ophthalmic segment aneurysms that were surgically repaired, 11 (6.4%) experienced new permanent neurological deficits, including six instances of complete visual loss. There was one postoperative death (0.6%) related to a middle cerebral artery infarction. Transient morbidity occurred in 18 patients (10.4%), including cerebrospinal fluid rhinorhea (10 patients), oculomotor nerve palsy (four patients) and transient dysphasia (four patients). A total of 142 aneurysms (78.0%) had documented postoperative angiography. Surgical treatment resulted in 135 (95.1%) complete obliterations and seven (4.9%) neck remnants. Retreatment was performed in three patients (1.7%). Logistic regression analysis of risk factors revealed that age (p < 0.02), aneurysm size (p < 0.01) and the use of temporary clipping (p < 0.01) were significant negative predictors of outcome. The risk associated with surgical repairs for unruptured ophthalmic segment aneurysms is no greater than aneurysms in other locations (6.4% morbidity; 0.6% mortality) and no more hazardous than outcomes achieved by alternative therapies. The robustness of aneurysm repair achieved by open microsurgery is an important consideration.