Long-term treatment outcomes and natural course of low-grade intracranial dural arteriovenous fistulas.

OBJECTIVE: In contrast to high-grade dural arteriovenous fistula (dAVF), low-grade dAVF is mainly associated with tinnitus and carries a low risk of morbidity and mortality. It remains unclear whether the benefits of active interventions outweigh the associated risk of complications in low-grade dAVF. METHODS: The authors conducted a retrospective single-center study that included all consecutive patients diagnosed with an intracranial low-grade dAVF (Cognard type I and IIa) during 2012-2022 with DSA. The authors analyzed symptom relief, symptomatic angiographic cure, treatment-related complications, risk for intracerebral hemorrhage (ICH), and mortality. All patients were followed up until the end of 2022. RESULTS: A total of 81 patients were diagnosed with a low-grade dAVF. Of these, 48 patients (59%) underwent treatment (all primary endovascular treatments), and 33 patients (41%) did not undergo treatment. Nine patients (19%) underwent retreatments. Angiographic follow-up was performed after median (IQR) 7.7 (6.1-24.1) months by means of DSA (mean 15.0, median 6.4 months, range 4.5-83.4 months) or MRA (mean 29.3, median 24.7 months, range 5.9-62.1 months). Symptom control was achieved in 98% of treated patients after final treatment. On final angiographic follow-up, 73% of patients had a completely occluded dAVF. There were 2 treatment-related complications resulting in 1 transient (2%) and 1 permanent (2%) neurological complication. One patient showed recurrence and progression of a completely occluded low-grade dAVF to an asymptomatic high-grade dAVF. No cases of ICH- or dAVF-related mortality were found in either treated patients (median [IQR] follow-up 5.1 [2.0-6.8] years) or untreated patients (median [IQR] follow-up 5.7 [3.2-9.0] years). CONCLUSIONS: Treatment of low-grade dAVF provides a high rate of symptom relief with small risks for complications with neurological sequela. The risks of ICH and mortality in patients with untreated low-grade dAVF are minimal. Symptoms may not reveal high-grade recurrence, and radiological follow-up may be warranted in selected patients with treated low-grade dAVF. An optimal radiographic follow-up regimen should be developed by a future prospective multicenter registry.

Recurrence of brain arteriovenous malformations in pediatric patients: a long-term follow-up study.

BACKGROUND: Previously thought to be congenital, AVMs have shown evidence of de-novo formation and continued growth, thus shifting thoughts on their pathophysiology. Pediatric AVM patients have been reported to be more prone to develop AVM recurrence after a seemingly complete cure. Therefore, we assessed the risk of AVM treated in childhood to recur in adulthood after a long-term follow-up in our own cohort. METHODS: Control DS-angiography was arranged during 2021-2022 as part of a new protocol for all AVM patients who were under 21 years of age at the time of their treatment and in whom the treatment had occurred at least five years earlier. Angiography was offered only to patients under 50 years of age at the time of the new protocol. The complete eradication of AVM after the primary treatment had been originally confirmed with DSA in every patient. RESULTS: A total of 42 patients participated in the late DSA control, and 41 of them were included in this analysis after excluding the patient diagnosed with HHT. The median age at the time of admission for AVM treatment was 14.6 (IQR 12-19, range 7-21 years) years. The median age at the time of the late follow-up DSA was 33.8 years (IQR 29.8-38.6, range 19.4-47.9 years). Two recurrent sporadic AVMs and one recurrent AVM in a patient with hereditary hemorrhagic telangiectasia (HHT) were detected. The recurrence rate was 4.9% for sporadic AVMs and 7.1% if HHT-AVM was included. All the recurrent AVMs had originally bled and been treated microsurgically. The patients with sporadic AVM recurrence had been smoking their whole adult lives. CONCLUSIONS: Pediatric and adolescent patients are prone to develop recurrent AVMs, even after complete AVM obliteration verified by angiography. Therefore, imaging follow-up is recommended.

Correlation between arteriovenous malformation nidus size and intraparenchymal hematoma volume in the event of rupture.

•Our study did not support the hypothesis that small AVMs lead to larger hematoma volumes in the event of a rupture.•AVM size did not correlate with the clinical severity of the bleeding as measured with HH and WFNS scores.•Larger supratentorial hematomas were associated with a more severe clinical manifestation and a poorer outcome.•In the event of a rupture, the AVM size did not correlate with the 2-4-month GOS.•AVICH score showed a good correlation with the 2-4-month GOS score.

Long-term health-related quality of life in patients with ruptured arteriovenous malformations treated in childhood.

OBJECTIVE: The aim of this study was to reveal the long-term health-related quality of life (HRQOL), educational level, and impact on occupation in 55 patients who experienced ruptured brain arteriovenous malformations (AVMs) that were treated during childhood. METHODS: In 2016, questionnaires including the 15D instrument were sent to all living patients older than 18 years (n = 432) in the Helsinki AVM database. The cohort was further specified to include only patients with ruptured AVMs who were younger than 20 years at the time of diagnosis (n = 55). Educational level was compared with the age-matched general population of Finland. The mean 15D scores were calculated for independent variables (Spetzler-Ponce classification, admission age, symptomatic epilepsy, and multiple bleeding episodes) and tested using the independent-samples t-test or ANCOVA. Linear regression was used to create a multivariate model. Bonferroni correction was used with multiple comparisons. RESULTS: The mean follow-up time from diagnosis to survey was 24.2 (SD 14.7) years. The difference in the mean 15D scores between Spetzler-Ponce classes did not reach statistical significance. The youngest age group (< 10 years at the time of diagnosis) performed less well on the dimension of usual activities than the older patients. Symptomatic epilepsy significantly reduced the long-term HRQOL. Multiple hemorrhages significantly reduced the scores on three dimensions: mobility, speech, and sexual activity. In the regression model, symptomatic epilepsy was the only significant predictor for a lower 15D score. The educational level of the cohort was for the most part comparable to that of the general population in the same age group. AVM was the reason for early retirement in 11% of the patients, while lowered performance because of the AVM was reported by 37% of the patients. CONCLUSIONS: Patients with ruptured AVMs treated in childhood can live an independent and meaningful life, even in the case of the highest-grade lesions. Symptomatic epilepsy significantly reduced the long-term HRQOL, highlighting the need for continuing support for these patients.

Comparing health-related quality of life in modified Rankin Scale grades: 15D results from 323 patients with brain arteriovenous malformation and population controls.

BACKGROUND: We wanted to understand how patients with different modified Rankin Scale (mRS) grades differ regarding their health-related quality of life (HRQoL) and how this affects the interpretation and dichotomization of the grade. METHODS: In 2016, all adult patients in our brain arteriovenous malformation (AVM) database (n = 432) were asked to fill in mailed letters including a questionnaire about self-sufficiency and lifestyle and the 15D HRQoL questionnaire. The follow-up mRS was defined in 2016 using the electronic patient registry and the questionnaire data. The 15D profiles of each mRS grade were compared to those of the general population and to each other, using ANCOVA with age and sex standardization. RESULTS: Patients in mRS 0 (mean 15D score = 0.954 ± 0.060) had significantly better HRQoL than the general population (mean = 0.927 ± 0.028), p < 0.0001, whereas patients in mRS 1-4 had worse HRQoL than the general population, p < 0.0001. Patients in mRS 1 (mean = 0.844 ± 0.100) and mRS 2 (mean = 0.838 ± 0.107) had a similar HRQoL. In the recently published AVM research, the most commonly used cut points for mRS dichotomization were between mRS 1 and 2 and between mRS 2 and 3. CONCLUSIONS: Using 15D, we were able to find significant differences in the HRQoL between mRS 0 and mRS 1 AVM patients, against the recent findings on stroke patients using EQ-5D in their analyses. Although the dichotomization cut point is commonly set between mRS 1 and 2, patients in these grades had a similar HRQoL and a decreased ability to continue their premorbid lifestyle, in contrast to patients in mRS 0.

Cigarette Smoking Is More Prevalent in Patients With Brain Arteriovenous Malformations Compared to General Population: A Cross-Sectional Population-Based Study.

BACKGROUND: Research on the prevalence of smokers in patients with brain arteriovenous malformation (AVM) remains nonexistent, even though smoking is a well-known risk factor for intracranial aneurysms. OBJECTIVE: To examine the prevalence and smoking habits of AVM patients. METHODS: Data on smoking habits were collected with a quality-of-life questionnaire mailed in 2016 to all patients in our large AVM database. These smoking data were supplemented with registry data derived from medical records. The prevalence of smokers was compared to that of the general population, derived from statistics of National Institute for Health and Welfare. Logit transformation of proportions and Students t distribution were used to calculate the 95% CIs for prevalence estimates. RESULTS: Of the 384 patients aged over 18 yr on admission, 277 (72.1%) returned the questionnaires in 2016. When compared to age, sex, and admission year matched general population, the proportion of smokers in AVM patients was 48% (CI = 41%-55%) and 19% (CI = 16%-21%) in the general population. The difference increased in older age groups; in those aged 65 to 77 yr, the percentage of smokers reached 73% (CI = 46%-90%), while the corresponding percentage in the general population was 7% (CI = 5%-9%). CONCLUSION: We observed considerably higher rates of smoking among AVM patients when compared to age, sex, and admission year matched general population. Our results suggest that in the development of AVMs, the role played by nicotine and other substances in tobacco smoke should be examined. Cigarette smoking could potentially be a common cerebrovascular risk factor.

Long-term health-related quality of life in 262 patients with brain arteriovenous malformation.

OBJECTIVE: To discover the health-related quality of life (HRQOL) of patients with treated arteriovenous malformation (AVM), we used the self-applicable HRQOL instrument, the 15D, and analyzed the scores in both in the whole study population and specified cohorts. METHODS: The 15D questionnaires were mailed to adult patients with AVM alive in 2016 (n = 432) in our database. Patients with completely eradicated AVM (n = 262) were included in a subsequent analysis. The results were compared with those of the general population standardized for age and sex. Subgroup analyses were conducted for epilepsy, number of bleeding episodes, location of the lesion, modified Rankin Scale score, and Spetzler-Ponce classification (SPC) using independent-samples t test or analysis of covariance. Tobit regression was used to explain the variance in the 15D score. RESULTS: Patients had impaired HRQOL compared to the reference population (p < 0.0001). Deep location, multiple bleeding episodes, and refractory epilepsy were associated with impaired HRQOL. Patients in SPC A and B had similar posttreatment 15D scores, whereas those in class C had an impaired HRQOL. Significant explanatory variables in the regression model were age, sex, number of bleeding episodes, refractory epilepsy, and SPC. CONCLUSIONS: With careful patient selection, patients in SPC B can reach as favorable HRQOL as those in SPC A provided the operation is successful. Multiple bleeding episodes should be prevented with effective treatment aiming at complete AVM obliteration. The postoperative treatment of patients with AVM should focus on preventing depressive symptoms, anxiety, and epileptic seizures. We encourage other research groups to use HRQOL instruments to fully understand the consequences of neurologic and neurosurgical diseases on patients' HRQOL.

Characteristics and Long-Term Outcome of 127 Children With Cerebral Arteriovenous Malformations.

BACKGROUND: Population-based long-term data on pediatric patients with cerebral arteriovenous malformations (AVMs) are limited. OBJECTIVE: To clarify the characteristics and long-term outcome of pediatric patients with AVM. METHODS: A retrospective analysis was performed on 805 consecutive brain AVM patients admitted to a single center between 1942 and 2014. The patients were defined as children if they were under 18 yr at admission. Children were compared to an adult cohort. Changing patterns of presentation were also analyzed by decades of admission. RESULTS: The patients comprised 127 children with a mean age of 12 yr. The mean follow-up time was 21 yr (range 0-62). Children presented more often with intracerebral hemorrhage (ICH) but less often with epilepsy than adults. Basal ganglia, cerebellar, and posterior paracallosal AVMs were more common in pediatric than in adult patients. Frontal and temporal AVMs, in contrast, were more common in adult than in pediatric patients. As the number of incidentally and epilepsy-diagnosed AVMs increased, ICH rates dropped in both cohorts. In total, 22 (82%) pediatric and 108 (39%) adult deaths were assessed as AVM related. After multivariate analysis, small AVM size and surgical treatment correlated with a favorable long-term outcome. CONCLUSION: Hemorrhagic presentation was more common in children than in adults. This was also reflected as lower prevalence of epileptic presentation in the pediatric cohort. Lobar and cortical AVM locations were less frequent, whereas deep and cerebellar AVMs were more common in children. Hemorrhagic presentation correlated negatively with incidentally and epilepsy-diagnosed AVMs. In children, AVM was a major cause of death, but in adults, other factors contributed more commonly to mortality.

The Application of the Novel Grading Scale (Lawton-Young Grading System) to Predict the Outcome of Brain Arteriovenous Malformation.

BACKGROUND: A supplementary grading scale (Supplemented Spetzler-Martin grade, Supp-SM) was introduced in 2010 as a refinement of the SM system to improve preoperative risk prediction of brain arteriovenous malformations (AVMs). OBJECTIVE: To determine the ability to predict surgical outcomes using the Supp-SM grading scale. METHODS: This retrospective study was conducted on 200 patients admitted to the Helsinki University Hospital between 2000 and 2014. The validity of the Supp-SM and SM grading systems was compared using the area under the receiver operating characteristic (AUROC) curves, with respect to the change between preoperative and early (3-4 mo) as well as final postoperative modified Rankin Scale (mRS) scores. RESULTS: The performance of the Supp-SM was superior to that of the SM grading scale in the early follow-up (3-4 mo): AUROC = 0.57 (95% confidence interval [CI]: 0.49-0.65) for SM and AUROC = 0.67 (95% CI: 0.60-0.75) for Supp-SM. The Supp-SM performance continued improving over SM at the late follow-up: AUROC = 0.63 (95% CI: 0.55-0.71) for SM and AUROC = 0.70 (95% CI: 0.62-0.77) for Supp-SM. The perforating artery supply, which is not part of either grading system, plays an important role in the early follow-up outcome (P = .008; odds ratio: 2.95; 95% CI: 1.32-6.55) and in the late follow-up outcome (P < .001; odds ratio: 5.89; 95% CI: 2.49-13.91). CONCLUSION: The Supp-SM grading system improves the outcome prediction accuracy and is a feasible alternative to the SMS, even for series with higher proportion of high-grade AVMs. However, perforators play important role on the outcome.

Arteriovenous Malformations of the Posterior Fossa: Focus on Surgically Treated Patients Presenting with Hemorrhage.

BACKGROUND: Arteriovenous malformations (AVMs) of the posterior fossa are demanding lesions that often present with rupture. Studies including outcome analyses in surgically operated patients with ruptured infratentorial AVMs are scarce. Certain anatomic and demographic features have shown associations with postoperative outcomes. METHODS: Eighty-six patients with infratentorial AVM were collected from our AVM database. Fifty-four patients were admitted from 1990 onward, and their demographic, lesion, and treatment characteristics were analyzed. The cohort was further refined to 38 consecutive patients with surgically treated ruptured infratentorial AVM admitted to our center between 1990 and 2014, and statistical analyses of factors influencing outcomes were conducted. RESULTS: Twenty-seven patients (69%) had a favorable outcome at early follow-up and 24 (67%) had a favorable outcome at final follow-up. Factors associated with poor outcome in early recovery on univariate analyses were deep venous drainage of the lesion (odds ratio [OR], 5.3; P = 0.037) and high Hunt & Hess score (P = 0.003). In the multivariate model, independent predictors for poor outcome were deep venous drainage (OR, 14.5; P = 0.010) and older age at admission (OR, 1.06; P = 0.028). The sole independent predictor for poor outcome at last follow-up was deep venous drainage (OR, 5.00; P = 0.046). The total follow-up time was 370 person-years. CONCLUSIONS: AVMs of the posterior fossa usually present with rupture and thus require prompt clinical treatment. The majority of surgically treated patients recover favorably. Our data show that venous drainage patterns have the greatest influence on the patient's postoperative condition. Other influencing factors include the severity of hemorrhage and patient age at admission.

Timing of surgery for ruptured supratentorial arteriovenous malformations.

BACKGROUND: There are conflicting opinions regarding the optimal waiting time to perform surgery after rupture of supratentorial arteriovenous malformations (AVMs) to achieve the best possible outcome. OBJECTIVE: To analyze factors influencing outcomes for ruptured supratentorial AVMs after surgery, paying particular attention to the timing of the surgery. METHODS: We retrospectively investigated 59 patients admitted to our center between 2000 and 2014 for surgical treatment of ruptured supratentorial AVMs. We evaluated the effect of timing of surgery and other variables on the outcome at 2-4 months (early outcome), at 12 months (intermediate outcome) after surgery, and at final follow-up at the end of 2016 (late outcome). RESULTS: Age over 40 years (OR 18.4; 95% CI 1.9-172.1; p = 0.011), high Hunt and Hess grade (4 or 5) before surgery (OR 13.5; 95% CI 2.1-89.2; p = 0.007), hydrocephalus on admission (OR 12.9; 95% CI 1.8-94.4; p = 0.011), and over 400 cm3 bleeding during surgery (OR 11.5; 95% CI 1.5-86.6; p = 0.017) were associated with an unfavorable early outcome. Age over 40 years (OR 62.8; 95% CI 2.6-1524.9; p = 0.011), associated aneurysms (OR 34.7; 95% CI 1.4-829.9; p = 0.029), high Hunt and Hess grade before surgery (OR 29.2; 95% CI 2.6-332.6; p = 0.007), and over 400 cm3 bleeding during surgery (OR 35.3; 95% CI 1.7-748.7; p = 0.022) were associated with an unfavorable intermediate outcome. Associated aneurysms (OR 8.2; 95% CI 1.2-55.7; p = 0.031), high Hunt and Hess grade before surgery (OR 5.7; 95% CI 1.3-24.3; p = 0.019), and over 400 cm3 bleeding during surgery (OR 5.8; 95% CI 1.2-27.3; p = 0.027) were associated with an unfavorable outcome at last follow-up. Elapsed time between rupture and surgery did not affect early or final outcome. CONCLUSIONS: Early surgery in patients with ruptured supratentorial arteriovenous malformation is feasible strategy, with late results comparable to those achieved with delayed surgery. Many other factors than timing of surgery play significant roles in long-term outcomes for surgically treated ruptured supratentorial AVMs.