Radiological surveillance of small unruptured intracranial aneurysms: a systematic review, meta-analysis, and meta-regression of 8428 aneurysms.

With the widespread use of imaging techniques, the possibility that an asymptomatic unruptured intracranial aneurysm (UIA) is detected has increased significantly. There is no established consensus regarding follow-up, duration, and frequency of such imaging surveillance. The objectives of this study include assessing the growth rate and rupture risk of small (less than 7mm) UIAs, identifying associated risk factors and providing an aneurysm surveillance protocol in appropriately selected patients. Systematic searches of Medline, Embase, and Cochrane Central were undertaken from database inception to March 2020 for published studies reporting the growth and rupture risks of small UIAs. Twenty-one studies reporting 8428 small UIAs were included in our meta-analysis. The pooled mean age was 61 years (95% CI: 55-67). The mean follow-up period for growth and rupture ranged from 11 to 108 months, with the pooled mean follow-up period across 14 studies being 42 months (95% CI: 33-51). Pooled overall growth rate was 6.0% (95% CI: 3.8-8.7). Pooled growth rates for aneurysms < 5mm and < 3 mm were 5.2% (95% CI: 3.0-7.9) and 0.8% (95% CI: 0.0-6.1), respectively. Pooled overall rupture rate was 0.4% (95% CI: 0.2-0.7). From the meta-regression analysis, having multiple aneurysms, smoking, hypertension, and personal history of SAH did not significantly predict growth, and a personal history of SAH, smoking, hypertension, and multiple aneurysms were not statistically significant predictors of rupture. Our findings suggest that small UIAs have low growth and rupture rates and very small UIAs have little or no risk for rupture. In the setting of incidental small UIAs, patients with multiple and/or posterior circulation aneurysms require more regular radiological monitoring.

Long-term clinical and mid-term radiographic follow-up of pure arterial malformations.

BACKGROUND: Pure arterial malformations (PAMs) are rare vascular lesions characterized by dilated, tortuous arterial loops without venous shunting. The natural history of PAMs remains unclear. We report the mid-term radiological and longer-term clinical outcomes of the largest series of patients with PAM. METHODS: Retrospective review at a tertiary academic referral center for patients with a PAM. Follow-up clinical and radiological data were collected and analyzed for clinical symptoms and radiographic changes. RESULTS: Twenty-five patients met the inclusion criteria. The mean age at presentation was 30.9 ± 14 years. Nineteen (76%) patients were female, and six (23.1%) were male. Eleven (44%) patients had ≥1 symptom at presentation, of which only 3 (12%) could be linked to PAM. The most common symptom was headache (n=8). PAMs involved a single vessel in 16 (64%) cases and ≥2 vessels in 9 cases (36%). Fifteen (60%) lesions were isolated to the anterior circulation compared to 6 (24%) in the posterior circulation. The most frequently involved vessel was the supraclinoid internal cerebral artery (36%). An associated saccular aneurysm was present in 32% of patients. Ten lesions were partially calcified. The mean radiographic and clinical follow-up was 21.9 ± 26.5 months and 44.6 ± 34.8 months, respectively. None of the patients developed new symptoms related to their lesion or radiographic progression over the duration of follow-up. CONCLUSIONS: PAMs are found most frequently in young, asymptomatic females. PAMs have a benign natural history and are best managed conservatively with serial imaging.

Unruptured intracranial aneurysms in patients over 80 years: natural history and management implications.

PURPOSE: Patients over the age of 80 years when diagnosed with an unruptured intracranial aneurysm (UIA) pose unique decision-making challenges due to shortened life-expectancy and increased risk of treatment. Thus, we investigated the risk of rupture and survival of a consecutive series of patients who were diagnosed with an UIA after the age of 80 years. METHODS: Data of consecutive patients with an UIA were reviewed, and patients were included in our study if they were first evaluated for a UIA by the senior author during their ninth decade of life. Outcomes were aneurysm rupture and overall survival after diagnosis. Survival was estimated from a Kaplan-Meier survival curve. Incidence of risk factors was compared to a population of patients less than 65 years who were seen by the senior author over the same time period. RESULTS: Eighty-three patients who were over 80 years when diagnosed with a UIA were included in this study. In our population, there is a risk of rupture of 3.2% per patient-year. One-, three-, and five-year survival rates for our population were estimated to be 92, 64, and 35%, respectively. When compared to patients under 65 years diagnosed with a UIA, "over 80" patients had a significantly higher incidence of hypertension, and a significantly lower incidence of smoking history and familial aneurysm history. CONCLUSIONS: In our study population, UIAs greater than 7 mm carry a non-negligible risk of rupture of 3.2% per patient-year, and further studies investigating the risk-to-benefit ratio of treatment in this population are warranted.

Risk of de novo aneurysm formation in patients with unruptured intracranial aneurysms.

BACKGROUND AND PURPOSE: The rate of de novo aneurysm formation in patients with unruptured aneurysm without history of subarachnoid hemorrhage is scarcely defined in literature. We report the incidence of de novo aneurysm formation in a large contemporary series of patients with unruptured intracranial aneurysm (UIA) undergoing serial neurovascular imaging. METHODS: Neurovascular imaging studies of 321 consecutive UIA patients with no prior history of subarachnoid hemorrhage, with at least 3 years of follow-up imaging, were reviewed by a neuroradiologist and a neurosurgeon. Rate of de novo aneurysm formation was reported on a per-patient and per-patient-year basis. RESULTS: Of the 321 included patients, three patients (0.9%) developed a de novo aneurysm over a mean follow-up period of 5.2 years, for an incidence rate of 0.18% per patient-year. No de novo aneurysms ruptured and all three were 2 mm in size. CONCLUSIONS: The rate of de novo aneurysm formation in patients with unruptured aneurysms and no history of subarachnoid hemorrhage is very low. These data are useful to advice patients with unruptured aneurysms from another aneurysm and to plan imaging follow-ups in these patients.

Risk factors for growth of conservatively managed unruptured intracranial aneurysms.

PURPOSE: Unruptured intracranial aneurysms (UIAs) occur in 2-3% of the adult population, but, once discovered, do not always require treatment. Untreated patients are usually followed with serial imaging to identify interval growth. In this study, we assessed the risk and risk factors for growth in a homogenous series of patients with conservatively managed UIAs. METHODS: Data from consecutive patients without history of subarachnoid hemorrhage and a conservatively managed UIA were retrospectively reviewed and only patients with at least 2 years of radiological follow-up were included in our study. We evaluated patients for the incidence of UIA growth, as well as analyzed risk factors for UIA growth. RESULTS: In 349 patients and 385 conservatively managed UIAs with 2210 patient-years of radiological follow-up, the risk of growth was 2.9% per aneurysm-year. Size (diameter greater than 5 mm), location (basilar artery apex), and weight loss (decrease in BMI over follow-up period) were all significantly associated with increased risk of UIA growth. There was a greater risk of UIA growth during the first 3 years of follow-up (7.5% per aneurysm-year) compared to the remaining years (2.7% per aneurysm-year). CONCLUSIONS: Conservatively managed UIAs in patients without prior history of SAH have a 2.9% risk of growth per aneurysm-year. UIAs greater than 5 mm in diameter, those located at the basilar artery apex, or patients who experience a decrease in BMI are more likely to grow and warrant closer follow-up. The risk of aneurysm growth is increased in the few years after diagnosis and decreases afterward.

Unruptured internal carotid artery bifurcation aneurysms: general features and overall results after modern treatment.

BACKGROUND: Internal carotid artery bifurcation aneurysms (ICAbifAs) present unique challenges to endovascular and surgical operators, and little is known about their natural history. We reviewed our institution's experience with ICAbifAs studying outcomes of surgical and endovascular management and natural history. METHODS: Consecutive patients with unruptured ICAbifAs evaluated and/or treated over an 8-year interval were studied. Baseline demographics, neurovascular risk factors, aneurysm location and size, clinical presentation, treatment recommendations, and outcomes were prospectively collected and retrospectively analyzed. Continuous variables were compared with Student's t test and categorical variables with Chi-square tests. RESULTS: Fifty-nine patients with 61 unruptured ICAbifAs were included. Seven aneurysms were treated surgically (11.5 %), 22 underwent endovascular treatment (36 %), and 32 were managed conservatively (52.5 %). In the surgical group, short- and long-term complete aneurysm occlusion rates were 100 % with no cases of perioperative or long-term permanent morbidity or treatment-related mortality. In the endovascular group, two patients (11.7 %) with giant aneurysms had perioperative thromboembolic events with transient morbidity. There was one case of aneurysm rupture at follow-up in a giant aneurysm treated with partial coil embolization. Complete/near-complete occlusion rates were 63 %. There was one case of aneurysm rupture after 114 aneurysm-years of follow-up in the conservative management group (0.89 %/year), but no ruptures were observed in small aneurysms selected for conservative management. CONCLUSIONS: Unruptured small ICAbifAs have a benign natural history. In patients selected for treatment, excellent results can be achieved in the vast majority of patients with judicious use of endovascular and surgical therapy.

Small (< 10-mm) incidentally found intracranial aneurysms, Part 2: treatment recommendations, natural history, complications, and short-term outcome in 212 consecutive patients.

OBJECT: The management of incidental small unruptured intracranial aneurysms (UIAs) is controversial and many factors need to be considered in the decision-making process. The authors describe a large consecutive series of patients harboring small incidental intracranial aneurysms. Treatment strategy, natural history, complications, and short-term outcomes are presented. METHODS: Between January 2008 and May 2011, the authors prospectively evaluated 212 patients with 272 small (< 10-mm) incidental aneurysms. Treatment recommendations (observation, endovascular treatment, or surgery), complications of treatment, and short-term outcomes were assessed. RESULTS: Recommended treatment consisted of observation in 125 patients, endovascular embolization in 64, and surgery in 18. Six patients were excluded from further analysis because they underwent treatment elsewhere. In the observation group, at a mean follow-up of 16.7 months, only 1 patient was moved to the embolization group. Seven (6%) of the 125 patients in the observation group died of causes unrelated to aneurysm. Sixty-five patients underwent 69 embolization procedures. The periprocedural permanent morbidity and mortality rates in patients undergoing endovascular treatment were 1.5% and 1.5%, respectively (overall morbidity and mortality rate 3.0%). In the surgery group no periprocedural complications were observed, although 1 patient did not return to her previous occupation. No aneurysmal rupture was documented in any of the 3 treatment groups during the follow-up period. CONCLUSIONS: A cautious and individualized approach to incidental UIAs is of utmost importance for formulation of a safe and effective treatment algorithm. Invasive treatment (either endovascular or surgery) can be considered in selected younger patients, certain "higher-risk" locations, expanding aneurysms, patients with a family history of aneurysmal hemorrhage, and in those who cannot live their lives knowing that they harbor the UIA. Although the complication rate of invasive treatment is very low, it is not negligible. The study confirms that small incidental UIAs deemed to be not in need of treatment have a very benign short-term natural history, which makes observation a reasonable approach in selected patients.

Incidence of hereditary thrombophilia in patients with cranial dural arteriovenous fistulae.

Dural arteriovenous fistulas (DAVFs) can develop as consequence of prior venous sinus thrombosis. However, the prevalence of prothrombotic conditions in patients with intracranial DAVFs is unknown and there is no consensus on the indications to screen for procoagulable conditions in these patients. We performed a retrospective review of patients presenting to our institution for management of cranial DAVF. Patient and DAVF characteristics were noted, in particular the incidence of hereditary thrombophilia (HT) detected by laboratory evaluation. Respective comparisons of patients with and without HT were performed using comparative statistics. There were 165 patients presenting for management of 171 DAVFs. A large proportion of DAVF were located at a large dural sinus (42.7%), which included superior sagittal, transverse, and sigmoid sinuses. On multivariate logistic regression analysis cortical venous drainage was independently associated with hemorrhagic presentation (OR 8.23, 95% CI 1.78-38.08; p = 0.007). A HT was detected in 18 of 61 patients (29.5%) who underwent a thrombophilia work-up. Location at a large dural sinus was not more common in patients with a HT (55.0% vs 54.5%; p = 0.97). There was also no difference in the presence of cortical venous drainage (56.5% vs 38.6%; p = 0.22) or hemorrhage on presentation (15.9% vs 5.0%; p = 0.22) in patients with and without a HT. In HT were found to be highly prevalent in our cohort, though our results do not suggest their presence greatly influences DAVF pathophysiology. Screening for procoagulable states is indicated in selected patients with an intracranial DAVF.

Natural history of untreated unruptured intracranial aneurysms in the elderly.

BACKGROUND: The effect of age on risk of intracranial aneurysm rupture is not well understood. We investigated the clinical course of patients 65 years and older with conservatively managed unruptured intracranial aneurysms (UIA) and determined risk factors for rupture in this population. METHODS: We reviewed prospectively collected data on baseline characteristics and long-term follow-up for patients aged 65 years and older with an UIA that were initially managed with observation. The association between patient and aneurysmal characteristics and risk of rupture was performed using a multivariate Cox proportional hazard regression model. RESULTS: There were 214 patients (mean age: 74.7 years, SD: 6.0) included in our study. The median follow-up time was 3.7 years, with a cumulative follow-up time of 883.7 person-years. During the study period, seven patients (3.3%) received interventional treatment of their UIA and eight patients (3.7%) experienced aneurysmal subarachnoid hemorrhage, yielding an annual risk of rupture of 0.9%. All aneurysms that ruptured were at least 10 mm in size. Increasing patient age [unit relative risk (RR) 1.19, 95% CI: 1.07-1.36, P=0.002], larger aneurysmal size (unit RR 1.10, 95% CI: 1.02-1.17, P=0.021), and increasing PHASES Score (unit RR 1.62, 95% CI: 1.32-2.06, P<0.001) were associated with higher risk of rupture. CONCLUSIONS: Our data do not suggest that UIA in older patients carry a high risk of rupture. A conservative approach appears justified in these patients, with the exception of selected patients with larger aneurysms (>10 mm in diameter) and low risk of interventional procedure.

Cavernous sinus aneurysms: risk of growth over time and risk factors.

OBJECTIVE: Cavernous internal carotid artery (ICA) aneurysms are frequently diagnosed incidentally and the benign natural history of these lesions is well known, but there is limited information assessing the risk of growth in untreated patients. The authors sought to assess and analyze risk factors in patients with cavernous ICA aneurysms and compare them to those of patients with intracranial berry aneurysms in other locations. METHODS: Data from consecutive patients who were diagnosed with a cavernous ICA aneurysm were retrospectively reviewed. The authors evaluated patients for the incidence of cavernous ICA aneurysm growth and rupture. In addition, the authors analyzed risk factors for cavernous ICA aneurysm growth and compared them to risk factors in a population of patients diagnosed with intracranial berry aneurysms in locations other than the cavernous ICA during the same period. RESULTS: In 194 patients with 208 cavernous ICA aneurysms, the authors found a high risk of aneurysm growth (19.2% per patient-year) in patients with large/giant aneurysms. Size was significantly associated with higher risk of growth. Compared to patients with intracranial berry aneurysms in other locations, patients with cavernous ICA aneurysms were significantly more likely to be female and have a lower incidence of hypertension. CONCLUSIONS: Aneurysms of the cavernous ICA are benign lesions with a negligible risk of rupture but a definite risk of growth. Aneurysm size was found to be associated with aneurysm growth, which can be associated with new onset of symptoms. Serial follow-up imaging of a cavernous ICA aneurysm might be indicated to monitor for asymptomatic growth, especially in patients with larger lesions.

Differences between patient- and professional-reported modified Rankin Scale score in patients with unruptured aneurysms.

OBJECTIVE: Clinical trials forming the basis of current guidelines for the management of intracranial aneurysms have relied on patient-reported modified Rankin Scale (mRS) scores to assess functional outcome. The effect of patient demographics on perception of disability and, by extension, patient-reported mRS score, is not well understood. METHODS: A consecutive series of patients with a previously treated or untreated unruptured intracranial aneurysm (UIA) prospectively underwent a structured interview with a trained nurse. At the conclusion of this interview, the patients were assigned an mRS score in accordance with their degree of disability. During the same visit, patients were also required to grade themselves on a paper sheet containing the mRS and corresponding information. Data on patient and aneurysm characteristics were also collected during the same visit. Agreement between patient- and nurse-reported mRS scores was assessed using Cohen's kappa coefficient. The effect of patient demographics on the frequency of higher patient- than nurse-reported mRS scores was assessed using the Pearson's chi-square and Fisher's exact tests. RESULTS: A total of 209 patients with a UIA were included in the study, 38 of whom (18.2%) had undergone previous treatment. The majority of patients were female (161/209, 77.0%), and the mean age of the cohort was 60.2 years (SD 13.7 years). Agreement between patient- and nurse-reported mRS scores occurred in 72.7% of cases (95% CI 66.3%-78.3%), with a kappa coefficient of 0.58 (95% CI 0.49-0.67). Patients younger than 75 years were more likely to report a higher mRS score than the nurse (19.4% vs 3.4%, p = 0.034). Among female patients, those without a college degree were more likely to report a higher mRS score than the nurse (22.5% vs 9.5%, p = 0.035). CONCLUSIONS: The results suggest that patient demographics may influence perception of disability. These findings should be considered when using patient-reported mRS scores to determine functional outcome.

Armband activity monitor data do not correlate with reported pain scores in patients receiving vertebroplasty.

BACKGROUND: Prior research on the efficacy of vertebroplasty has focused primarily on subjective, patient-reported outcomes. OBJECTIVE: To apply an armband activity monitor (SenseWear by BodyMedia Inc, USA) to patients presenting for consideration for vertebroplasty and to determine the correlation between patient-reported outcomes and quantitative activity metrics at baseline and 30 days after presentation. MATERIALS AND METHODS: Nineteen patients were enrolled (15 receiving vertebroplasty, 4 not receiving vertebroplasty). Patients reported their average pain over the past 24 hours and completed the Roland-Morris disability questionnaire at baseline and 30 days. Patients wore the SenseWear Armband activity monitor for a median of 4 days at baseline and at the 30-day time period to assess steps, metabolic equivalents expended, sedentary activity time, moderate activity time, sleep efficiency, and total sleep time. Pain and disability scores were correlated with activity monitor metrics using linear regression analysis. RESULTS: Changes in reported average pain in the past 24 hours and disability scores were not significantly different between vertebroplasty and non-vertebroplasty groups (p>0.05). Changes in activity monitor data were not significantly different between the vertebroplasty and non-vertebroplasty groups (p>0.05). None of the correlations between the reported pain or disability scores and the activity monitor data were significant. CONCLUSIONS: Activity monitors can be used to objectively record changes in activity following vertebroplasty procedures. Patient-reported pain or disability scores do not correlate with activity monitor-measured activity or sleep metrics.

Item response theory analysis to evaluate reliability and minimal clinically important change of the Roland-Morris Disability Questionnaire in patients with severe disability due to back pain from vertebral compression fractures.

BACKGROUND CONTEXT: The majority of validation done on the Roland-Morris Disability Questionnaire (RMDQ) has been in patients with mild or moderate disability. There is paucity of research focusing on the psychometric quality of the RMDQ in patients with severe disability. PURPOSE: To evaluate the psychometric quality of the RMDQ in patients with severe disability. STUDY DESIGN/SETTING: Observational clinical study. SAMPLE: The sample consisted of 214 patients with painful vertebral compression fractures who underwent vertebroplasty or kyphoplasty. OUTCOME MEASURES: The 23-item version of the RMDQ was completed at two time points: baseline and 30-day postintervention follow-up. METHODS: With the two-parameter logistic unidimensional item response theory (IRT) analyses, we derived the range of scores that produced reliable measurement and investigated the minimal clinically important difference (MCID). RESULTS: Scores for 214 (100%) patients at baseline and 108 (50%) patients at follow-up did not meet the reliability criterion of 0.90 or higher, with the majority of patients having disability due to back pain that was too severe to be reliably measured by the RMDQ. Depending on methodology, MCID estimates ranged from 2 to 8 points and the proportion of patients classified as having experienced meaningful improvement ranged from 26% to 68%. A greater change in score was needed at the extreme ends of the score scale to be classified as having achieved MCID using IRT methods. CONCLUSIONS: Replacing items measuring moderate disability with items measuring severe disability could yield a version of the RMDQ that better targets patients with severe disability due to back pain. Improved precision in measuring disability would be valuable to clinicians who treat patients with greater functional impairments. Caution is needed when choosing criteria for interpreting meaningful change using the RMDQ.

Evolution of transthoracic fine needle aspiration and core needle biopsy practice: A comparison of two time periods, 1996-1998 and 2003-2005.

To examine the performance of our large pulmonary transthoracic fine needle aspiration/core biopsy (FNA/CB) practice over time, we performed a retrospective analysis of data from 333 consecutive procedures performed in 1996-1998 and 568 consecutive procedures performed in 2003-2005. Fluoroscopic guidance was performed more frequently in the earlier cohort, while a larger majority of procedures in the later cohort were by computed tomography (CT-guidance). A follow-up histologic diagnosis of cancer or clinical evidence of disease was considered the gold-standard. FNA/CB procedures during the later time period were performed on smaller lesions overall (3.60 cm versus 2.97 cm; P = 0.003) and malignant lesions also tended to be smaller (3.87 cm versus 3.14 cm; P = 0.006). Minimal improvements in sensitivity (94% versus 91%), specificity (99% versus 95%), diagnostic accuracy (95% versus 92%), negative predictive value (NPV) (80% versus 74%), and positive predictive value (PPV) (100% versus 99%) were noted during 2003-2005 when compared with 1996-1998 in all lesions. Larger improvements in sensitivity (94% versus 73%), diagnostic accuracy (95% versus 79%), and NPV (79% versus 50%) were identified in very small lesions (<1 cm) in the later patient cohort in comparison to the earlier patient cohort, as well as a significant decrease in total procedure complications. CT-guided transthoracic FNA/CB continues to be a very effective tool in our practice assessing lung lesions and performance has improved considerably at our institution for very small lesions.