Effectiveness of an Annular Closure Device to Prevent Recurrent Lumbar Disc Herniation: A Secondary Analysis With 5 Years of Follow-up.

Importance: Patients with large annular defects following lumbar microdiscectomy for disc herniation are at increased risk for symptomatic recurrence and reoperation. Objective: To determine whether a bone-anchored annular closure device in addition to lumbar microdiscectomy resulted in lower reherniation and reoperation rates vs lumbar microdiscectomy alone. Design, Setting, and Participants: This secondary analysis of a multicenter randomized clinical trial reports 5-year follow-up for enrolled patients between December 2010 and October 2014 at 21 clinical sites. Patients in this study had a large annular defect (6-10 mm width) following lumbar microdiscectomy for treatment of lumbar disc herniation. Statistical analysis was performed from November to December 2020. Interventions: Lumbar microdiscectomy with additional bone-anchored annular closure device (device group) or lumbar microdiscectomy only (control group). Main Outcomes and Measures: The incidence of symptomatic reherniation, reoperation, and adverse events as well as changes in leg pain, Oswestry Disability Index, and health-related quality of life when comparing the device and control groups over 5 years of follow-up. Results: Among 554 randomized participants (mean [SD] age: 43 [11] years; 327 [59%] were men), 550 were included in the modified intent-to-treat efficacy population (device group: n = 272; 270 [99%] were White); control group: n = 278; 273 [98%] were White) and 550 were included in the as-treated safety population (device group: n = 267; control group: n = 283). The risk of symptomatic reherniation (18.8% [SE, 2.5%] vs 31.6% [SE, 2.9%]; P < .001) and reoperation (16.0% [SE, 2.3%] vs 22.6% [SE, 2.6%]; P = .03) was lower in the device group. There were 53 reoperations in 40 patients in the device group and 82 reoperations in 58 patients in the control group. Scores for leg pain severity, Oswestry Disability Index, and health-related quality of life significantly improved over 5 years of follow-up with no clinically relevant differences between groups. The frequency of serious adverse events was comparable between the treatment groups. Serious adverse events associated with the device or procedure were less frequent in the device group (12.0% vs 20.5%; difference, -8.5%; 95% CI, -14.6% to -2.3%; P = .008). Conclusions and Relevance: In patients who are at high risk of recurrent herniation following lumbar microdiscectomy owing to a large defect in the annulus fibrosus, this study's findings suggest that annular closure with a bone-anchored implant lowers the risk of symptomatic recurrence and reoperation over 5 years of follow-up. Trial Registration: ClinicalTrials.gov Identifier: NCT01283438.

The rupture of an anterior communicating artery aneurysm does not associate with an asymmetry in the A1 or A2 arteries: a retrospective study of radiological features.

BACKGROUND AND OBJECTIVES: Although the formation and rupture risk of an anterior communicating artery (ACoA) aneurysm has been the subject of many studies, no previous study has primarily searched for the relationship of the parent and daughter vessels and the impact of their size/diameter ratio on the potential rupture risk of an AcoA aneurysm. The objective of this study is to explore this link and to further analyse the surrounding vasculature of the anterior communicating artery aneurysm. MATERIALS AND METHODS: We conducted a retrospective analysis of 434 patients: 284 patients with an ACoA aneurysm (121 unruptured and 162 ruptured) and 150 control patients without an ΑCoA aneurysm. Radiological angiography investigations were used to assess the diameter ratios of the parent vessels in addition to ACoA aneurysm morphology parameters. RESULTS: When comparing the ruptured to the unruptured cases, we observed no significant difference in the parent or daughter vessel diameter ratios. Younger patient age (OR 0.96, p = 0.00) and a higher aneurysm size ratio (OR 1.10, p = 0.02) were of prognostic importance concerning the rupture risk of the aneurysm. The A1 diameter ratio and the A2 diameter were not statistically significant (OR 1.00, p = 0.99, and OR 3.38, p = 0.25 respectively). CONCLUSIONS: In our study, we focused on asymmetry in the parent and daughter vessels as well as traditional ACoA aneurysm morphological characteristics. We were able to label younger patient age and a greater size ratio as independent prognostic factors for ACoA aneurysm rupture. We were unable to label parent and daughter vessel asymmetry as prognostic factors. To validate our findings, parent and daughter vessel asymmetry should be subjected to future prospective studies.

Asymmetry of P1 and vertebral arteries is not related to basilar tip aneurysm development or rupture.

OBJECTIVE: Lately, morphological parameters of the surrounding vasculature aside from aneurysm size, specific for the aneurysm location, e.g., posterior cerebral artery angle for basilar artery tip aneurysms, could be identified to correlate with the risk of rupture. We examined further image-based morphological parameters of the aneurysm surrounding vasculature that could correlate with the growth or the risk of rupture of basilar artery tip aneurysms. METHODS: Data from 83 patients with basilar tip aneurysms (27 not ruptured; 56 ruptured) and 100 control patients were assessed (50 without aneurysms and 50 with aneurysms of the anterior circle of Willis). Anatomical parameters of the aneurysms were assessed and analyzed, as well as of the surrounding vasculature, namely the asymmetry of P1 and the vertebral arteries. RESULTS: Patients with basilar tip aneurysm showed no significant increase in P1 or vertebral artery asymmetry compared with the control patients or patients with aneurysms of the anterior circulation, neither was there a significant difference in asymmetry between cases with ruptured and unruptured aneurysms. Furthermore, we observed no significant correlations between P1 asymmetry and the aneurysm size or number of lobuli in the aneurysms. CONCLUSION: We observed no significant difference in aneurysm size, rupture, or lobulation associated with P1 or vertebral artery (surrounding vasculature) asymmetry. Therefore, the asymmetry of the surrounding vessels does not seem to be a promising morphological parameter for the evaluation of probability of rupture and growth in basilar tip aneurysms in future studies.

Rupture of intracranial aneurysms in patients with blunt head trauma: Review of the literature.

INTRODUCTION: With a prevalence of 1-5 %, intracranial aneurysms are common. However, only 20-50 % of these aneurysms will rupture during a person's lifetime. This often happens spontaneously without exogenous factors. In the present study we reviewed the literature concerning the relation between trauma and rupture of a pre-existing aneurysm. METHODS: All studies that reported a causal relation between trauma and rupture of a pre-existing aneurysm were included, irrespective of study design. They were limited though to those written in English or German. Excluded were studies with traumatic aneurysms, studies where the rupture of an aneurysm lead to trauma and studies with doubts about the order of events. RESULTS: Thirteen studies with twenty-two cases of ruptured aneurysm in context with trauma and two unpublished cases were included. Fourteen patients were involved in a fight, seven patients in a bike/motorbike/bus accident and three got hit on the head in a setting outside of interpersonal violence. The aneurysm was located in internal carotid artery in most cases (7/24). The clear majority of patients (19/24) did not survive. CONCLUSION: Arteries and aneurysms can rupture in context with head trauma although this is rarely the case. Patients after head trauma with typical blood pattern for aneurysmal SAH in the native CT scan should receive conventional angiography to exclude a vascular or aneurysmal rupture, even when CT-angiography is inconspicuous.

Comparison of Different Hybrid Techniques for the Treatment of Multilevel Cervical Degenerative Disc Disease-Analysis of Prospectively Collected Clinical, Radiologic, and Psychological Parameters.

OBJECTIVE: Conventional surgical treatment of multilevel cervical disc disease is based on anterior cervical discectomy and fusion (ACDF). However, fusion alters the biomechanics of the spine, potentially resulting in accelerated adjacent segment degeneration. To improve clinical outcomes, hybrid surgery, combining cervical disc arthroplasty with fusion, has been developed. Cervical total disc replacement (TDR) has been shown to keep the motion of adjacent segment, and a dynamic cervical implant (DCI) was shown to provide cervical dynamic stability under nonfusion. However, curative and unwanted side effects of the new therapy options TDR and DCI for treating multilevel cervical degenerative disc disease are still unknown. PATIENTS AND METHODS: This analysis is based on 88 patients treated for multilevel cervical degenerative disc disease with ACDF only (56 patients), DCI hybrid (17 patients), and TDR hybrid (15 patients) between June 2008 and November 2015. The mean follow-up was 19.5 months. Visual analog scale (VAS), Neck Disability Index, and quality-of-life measurements were assessed via questionnaires. RESULTS: The VAS scores decreased significantly in all 3 groups (P < 0.001), but the TDR group showed the greatest reduction in VAS score compared with ACDF and DCI (both P < 0.05). The overall range of motion (ROM) and the segmental ROM at the treated levels showed significant decreases in all 3 groups. Although there was no difference in the overall ROM at final follow-up among the operatively treated groups, the ROM of the treated segment was lowest in the ACDF group (P = 0.002). In terms of heterotopic ossification, patients undergoing TDR showed the best prognosis. CONCLUSIONS: These results indicate that both TDR hybrid and DCI hybrid are effective and safe procedures for the treatment of multilevel degenerative disc disease. However, there is no definitive evidence that DCI or TDR arthroplasty lead to better intermediate-term results than ACDF over an average observation time of 19.5 months.

Adrenoceptor Expression during Intervertebral Disc Degeneration.

Healthy and degenerating intervertebral discs (IVDs) are innervated by sympathetic nerves, however, adrenoceptor (AR) expression and functionality have never been investigated systematically. Therefore, AR gene expression was analyzed in both tissue and isolated cells from degenerated human IVDs. Furthermore, human IVD samples and spine sections of wildtype mice (WT) and of a mouse line that develops spontaneous IVD degeneration (IVDD, in SM/J mice) were stained for ARs and extracellular matrix (ECM) components. In IVD homogenates and cells α1a-, α1b-, α2a-, α2b-, α2c-, ß1-, and ß2-AR genes were expressed. In human sections, ß2-AR was detectable, and its localization parallels with ECM alterations. Similarly, in IVDs of WT mice, only ß2-AR was expressed, and in IVDs of SM/J mice, ß2AR expression was stronger accompanied by increased collagen II, collagen XII, decorin as well as decreased cartilage oligomeric matrix protein expression. In addition, norepinephrine stimulation of isolated human IVD cells induced intracellular signaling via ERK1/2 and PKA. For the first time, the existence and functionality of ARs were demonstrated in IVD tissue samples, suggesting that the sympathicus might play a role in IVDD. Further studies will address relevant cellular mechanisms and thereby help to develop novel therapeutic options for IVDD.

Association between aneurysm hemodynamics and wall enhancement on 3D vessel wall MRI.

OBJECTIVE: Aneurysm wall enhancement (AWE) on 3D vessel wall MRI (VWMRI) has been suggested as an imaging biomarker for intracranial aneurysms (IAs) at higher risk of rupture. While computational fluid dynamics (CFD) studies have been used to investigate the association between hemodynamic forces and rupture status of IAs, the role of hemodynamic forces in unruptured IAs with AWE is poorly understood. The authors investigated the role and implications of abnormal hemodynamics related to aneurysm pathophysiology in patients with AWE in unruptured IAs. METHODS: Twenty-five patients who had undergone digital subtraction angiography (DSA) and VWMRI studies from September 2016 to September 2017 were included, resulting in 22 patients with 25 IAs, 9 with and 16 without AWE. High-resolution CFD models of hemodynamics were created from DSA images. Univariate and multivariate analyses were performed to investigate the association between AWE and conventional morphological and hemodynamic parameters. Normalized MRI signal intensity was quantified and quantitatively associated with wall shear stresses (WSSs) for the entire aneurysm sac, and in regions of low, intermediate, and high WSS. RESULTS: The AWE group had lower WSS (p < 0.01) and sac-averaged velocity (p < 0.01) and larger aneurysm size (p < 0.001) and size ratio (p = 0.0251) than the non-AWE group. From multivariate analysis of both hemodynamic and morphological factors, only low WSS was found to be independently associated with AWE. Sac-averaged normalized MRI signal intensity correlated with WSS and was significantly different in regions of low WSS compared to regions of intermediate (p = 0.018) and high (p < 0.001) WSS. CONCLUSIONS: The presence of AWE was associated with morphological and hemodynamic factors related to rupture risk. Low WSS was found to be an independent predictor of AWE. Our findings support the hypothesis that low WSS in IAs with AWE may indicate a growth and remodeling process that may predispose such aneurysms to rupture; however, a causality between the two cannot be established.

[Who benefits from medical technical innovations? : A medical and medical economic analysis using the example of lumbar disc surgery]. / Wer profitiert von medizinisch-technischen Innovationen? : Eine medizinische und medizinökonomische Betrachtung am Beispiel lumbaler Bandscheibenoperationen.

Further developments in disease diagnosis and treatment are of immense relevance for advancements in medical care of the population. A detailed cost-benefit analysis of direct and indirect costs is usually unavailable. In the current article, these aspects are investigated using prospectively collected randomized data over two years. Specifically, the surgical treatment of a herniated lumbar disc is addressed, and whether a newly introduced technique (e.g., annular closure device) can lead to a better quality of care and increased patient satisfaction when performed during the standard operation, while also being economically viable.

The Role of Stabilization-Free Microsurgical Decompression in the Surgical Treatment of Spinal Metastases.

OBJECTIVE: Symptomatic spine metastases are found in about 10% of patients with cancer. As the long-term survival of patients with carcinoma rises, the number of patients with symptomatic spine metastases is also increasing. In our tertiary referral center, patients usually present rapidly progressive neurologic disorders, which require an urgent treatment decision. Treatment options include extensive 360° stabilizations. These complex interventions are not always readily available. We examined the extent to which the patient population benefited from decompressive surgery without stabilization. We hypothesize that patients benefit from merely dorsal decompression, which preserves stability when they experience symptomatic spine metastases. METHODS: We performed a retrospective analysis of electronic patient data from 19 patients, who were treated for symptomatic spine metastases by hemilaminectomy between 2009 and 2017. We evaluated the preoperative and postoperative neurologic functions using the American Spinal Injury Association (ASIA) Impairment Scale. A comparative literature analysis was carried out to assess the Spinal Neoplastic Instability Score, Tokuhashi score, and Tomita score. RESULTS: Nine participants had prostate cancer, 4 had mammary carcinoma, 3 had bronchial carcinoma, and 3 had other cancers. The median preoperative ASIA score was C, postoperatively, the score significantly improved to D (sign test P = 0.002). None of the patients needed stabilization within the follow-up period of up to 56 months. CONCLUSIONS: In our patient population, minimal intervention could significantly improve neurologic disorders. This outcome was seen over the whole study period. Even though different scoring systems suggest stabilization, our results show that spinal decompression alone might be indicated as well.

Lumbar disc reherniation prevention with a bone-anchored annular closure device: 1-year results of a randomized trial.

BACKGROUND: The risk of recurrent herniation after lumbar discectomy is highest during the first postoperative year. The purpose of this study was to determine whether implantation of a bone-anchored annular closure device (ACD) following limited lumbar discectomy reduced the risk of recurrent herniation and complications during the first year of follow-up compared to limited lumbar discectomy alone (Controls) and whether this risk was influenced by patient characteristics. METHODS: In this randomized multicenter trial, patients with symptomatic lumbar disc herniation and with a large annular defect following limited lumbar discectomy were randomized to bone-anchored ACD or Control groups. The risks of symptomatic reherniation, reoperation, and device- or procedure-related serious adverse events were reported over 1 year of follow-up. RESULTS: Among 554 patients (ACD 276; Control 278), 94% returned for 1-year follow-up. Bone-anchored ACD resulted in lower risks of symptomatic reherniation (8.4% vs. 17.3%, P = .002) and reoperation (6.7% vs. 12.9%, P = .015) versus Controls. Device- or procedure-related serious adverse events through 1 year were reported in 7.1% of ACD patients and 13.9% of Controls (P = .009). No baseline patient characteristic significantly influenced these risks. CONCLUSIONS: Among patients with large annular defects following limited lumbar discectomy, additional implantation with a bone-anchored ACD lowered the risk of symptomatic reherniation and reoperation over 1 year follow-up. Device- or procedure-related serious adverse events occurred less frequently in the ACD group. These conclusions were not influenced by patient characteristics. ClinicalTrials.gov (NCT01283438).

The Disability Cascade: A Preventable Consequence of the Loss of Disc Height following Lumbar Microdiscectomy.

Lumbar discectomy is a mainstay surgical treatment for herniation of the lumbar discs and is effective at treating radicular symptomology. Despite the overall success of the procedure; the potential for reherniation and reoperation is significant. To avoid this potential recurrence, surgeons often perform discectomy more aggressively, removing a larger volume of nuclear material in the hopes of minimizing the likelihood of reherniation. This approach, while beneficial in minimizing the chance of reherniation, is associated with a volumetric reduction of the nucleus within the disc space, making the disc more prone to collapse and thus inducing a significant post-operative loss of disc height. While potentially minor in isolation, the loss of disc height, in fact, impacts several aspects of overall patient well-being. We hypothesize that the loss of disc height following discectomy causes an increase in pain and subsequent disability, the combination of which ultimately impacts socioeconomic factors affecting both the patient and the healthcare system as a whole. In this report, we outline the evidence in support of this disability cascade and provide recommendations on methods for limiting its impact. Given the current focus on cost-effectiveness in healthcare decision-making, methods for limiting this potentially damaging sequence of events must be investigated.

Clinical performance of a bone-anchored annular closure device in older adults.

Background: Lumbar discectomy is a common surgical procedure in middle-aged adults. However, outcomes of lumbar discectomy among older adults are unclear. Methods: Lumbar discectomy patients with an annular defect ≥6 mm width were randomized to receive additional implantation with a bone-anchored annular closure device (ACD, n=272) or no additional implantation (controls, n=278). Over 3 years follow-up, main outcomes were symptomatic reherniation, reoperation, and the percentage of patients who achieved the minimum clinically important difference (MCID) without a reoperation for leg pain, Oswestry Disability Index (ODI), SF-36 Physical Component Summary (PCS) score, and SF-36 Mental Component Summary (MCS) score. Results were compared between older (≥60 years) and younger (<60 years) patients. We additionally analyzed data from two postmarket ACD registries to determine consistency of outcomes between the randomized trial and postmarket, real-world results. Results: Among all patients, older patients suffered from crippling or bed-bound preoperative disability more frequently than younger patients (57.9% vs 39.1%, p=0.03). Among controls, female sex, higher preoperative ODI, and current smoking status, but not age, were associated with greater risk of reherniation and reoperation. Compared to controls, the ACD group had lower risk of symptomatic reherniation (HR=0.45, p<0.001) and reoperation (HR=0.54, p=0.008), with risk reductions comparable in older vs younger patients. The percentage of patients achieving the MCID without a reoperation was higher in the ACD group for leg pain (81% vs 72%, p=0.04), ODI (82% vs 73%, p=0.03), PCS (85% vs 75%, p=0.01), and MCS (59% vs 46%, p=0.007), and this benefit was comparable in older versus younger patients. Comparable benefits in older patients were observed in the postmarket ACD registries. Conclusion: Outcomes with lumbar discectomy and additional bone-anchored ACD are superior to lumbar discectomy alone. Older patients derived similar benefits with additional bone-anchored ACD implantation as younger patients.

New insights into the natural course and clinical relevance of Modic changes over 2 years following lumbar limited discectomy: analysis of prospective collected data.

PURPOSE: Few retrospective studies have addressed Modic changes (MC) following lumbar spine surgery, though it is usually assumed that MC increase in grade and incidence. To test this conventional wisdom, we investigated the natural course of MC following primary lumbar limited discectomy with two-year follow-up. In addition, a possible clinical relevance to those changes was assessed. METHODS: The data of the control group (278 subjects) of a prospective randomized, controlled trial (RCT) were evaluated retrospectively. RESULTS: We did not observe a simple increase in MC with regard to grade. There is variable activity observed in Type 2 (at 12 months) and in Type 1 (at 24 months). Conversion from one grade to another may occur and may be upward or downward. The incidence of MC increased slightly over time, as after surgery a decreasing percentage of the study group remained without MC over two years (1 year: 34% (85/250); 2 years: 30% (72/237)). Radiological parameters (rotation, translation, and spondylolisthesis) had no significant correlation to MC or MC subtypes. Lastly, we found that neither the different MC types nor their changes were correlated with clinical parameters (VAS back, VAS leg, ODI score) preoperatively or during follow-up. CONCLUSION: The pattern of Modic changes following lumbar limited discectomy is complex, not simply increasing. There is variable activity in MC Types 1 and 2 at the different time points of follow-up, and conversion from a higher grader to a lower one or vice versa is possible. These slides can be retrieved under Electronic Supplementary Material.

Challenges in the Analysis of Longitudinal Pain Data: Practical Lessons from a Randomized Trial of Annular Closure in Lumbar Disc Surgery.

Purpose. To analyze leg pain severity data from a randomized controlled trial (RCT) of lumbar disc surgery using integrated approaches that adjust pain scores collected at scheduled follow-up visits for confounding clinical events occurring between visits. Methods. Data were derived from an RCT of a bone-anchored annular closure device (ACD) following lumbar discectomy versus lumbar discectomy alone (Control) in patients with large postsurgical annular defects. Leg pain was recorded on a 0 to 100 scale at 6 weeks, 3 months, 6 months, 1 year, and 2 years of follow-up. Patients with pain reduction ≥20 points relative to baseline were considered responders. Unadjusted analyses utilized pain scores reported at follow-up visits. Since symptomatic reherniation signifies clinical failure of lumbar discectomy, integrated analyses adjusted pain scores following a symptomatic reherniation by baseline observation carried forward for continuous data or classification as nonresponders for categorical data. Results. Among 550 patients (272 ACD, 278 Control), symptomatic reherniation occurred in 10.3% of ACD patients and in 21.9% of controls (p < 0.001) through 2 years. There was no difference in leg pain scores at the 2-year visit between ACD and controls (12 versus 14; p = 0.33) in unadjusted analyses, but statistically significant differences favoring ACD (19 versus 29; p < 0.001) in integrated analyses. Unadjusted nonresponder rates were 6.0% with ACD and 6.7% with controls (p = 0.89), but 15.7% and 27.8% (p = 0.001) in integrated analyses. The probability of nonresponse was 16.4% with ACD and 18.3% with controls (p = 0.51) in unadjusted analysis, and 23.7% and 31.2% (p = 0.04) in integrated analyses. Conclusion. In an RCT of lumbar disc surgery, an integrated analysis of pain severity that adjusted for the confounding effects of clinical failures occurring between follow-up visits resulted in different conclusions compared to an unadjusted analysis of pain scores reported at follow-up visits only.

Postoperative direct health care costs of lumbar discectomy are reduced with the use of a novel annular closure device in high-risk patients.

BACKGROUND CONTEXT: Lumbar discectomy is largely successful surgical procedure; however, reherniation rates in patients with large annular defects are as high as 27%. The expense associated with a revision surgery places significant burden on the healthcare system. PURPOSE: To compare the direct health care costs through 5 years follow-up of conventional discectomy (Control) with those of discectomy supplemented by an adjunctive annular closure device (ACD) in high-risk patients with large annular defects. STUDY DESIGN: This was a cost-effectiveness study. METHODS: All-cause index level reoperations were reviewed from a multicenter, randomized controlled superiority trial that allocated 554 high-risk discectomy patients with large annular defects to either control or ACD. Medicare and private insurer (Humana) direct costs were derived from a commercially available payer database to estimate costs in the US healthcare system, including those associated with facility, surgeon, imaging, follow-up visits, physical therapy, and injections. A 50:50 split between Medicare and commercial insurers was assumed for the base case analysis. The analysis was also performed on a 80:20 commercial:Medicare payer basis. For the base case scenario, a 2-year time horizon and outpatient cost setting was established for the index procedure. Repeat discectomy was assumed to be performed on a 60:40 outpatient-to-inpatient basis. Complications requiring surgery, revisions, and/or fusion were assumed to be managed in the inpatient setting. Total costs of reoperation and per-patient costs of reoperation were compared between groups for both forms of insurers. One author received consulting fees of <$50,000 for the completion of this study, and the other eight authors did not have any financial associations with the current work. Funding for this study was provided by Intrinsic Therapeutics, but all analyses, interpretation, and writing were performed independently by the authors. RESULTS: At two years follow-up, use of the ACD reduced the rate of symptomatic reherniations in a large defect population to 13% compared with 25% in the control group (p<.001). This reduction in symptomatic reherniations in the ACD group translated to a savings of $2,802 per patient in direct health care costs compared with Control at 2 years and $5,315 per patient by 5 years based on 50% private and 50% public (Medicare) payer split. Under the scenario of 80:20 private:public insurance reimbursement, the estimated direct cost savings were $3,215 and $6,099 per patient at 2- and 5-years postoperatively, respectively, with the use of the ACD. CONCLUSIONS: Symptomatic reherniation and reoperation rates were nearly double among control patients compared with ACD-treated patients, which translated to markedly greater per-patient healthcare costs in the control group, where the ACD was not used.

Prognostic Model for Chronic Shunt-Dependent Hydrocephalus After Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Patients with aneurysmal subarachnoid hemorrhage (aSAH) are at risk of the development of chronic shunt-dependent hydrocephalus. However, identification of shunt-dependent patients remains challenging. We sought to develop a prognostic model to identify patients with aSAH at risk of chronic shunt-dependent hydrocephalus. In addition to the well-known prognostic variables, blood clearance in the cerebrospinal fluid (CSF) spaces was considered. METHODS: We retrospectively analyzed the data from 227 patients treated at our institution from January 2012 to January 2016. The outcome was ventriculoperitoneal shunt placement within 30 days after aSAH. The candidate prognostic variables were patient age, World Federation of Neurological Surgeons grade and Fisher grade, external ventricular drainage, ventricular and intracerebral hemorrhage, and interval to blood clearance in the peripheral/basal CSF spaces. Adjustment for multiple testing was performed. Multivariable logistic regression analysis was used for model development. Bootstrapping was applied for internal validation. The model performance measures included indexes for explained variance (R2), calibration (graphic plot, Hosmer-Lemeshow test), and discrimination (c-statistic). RESULTS: Of the 227 patients, 90 (39.6%) required a ventriculoperitoneal shunt. The constructed prognostic model combined external ventricular drainage placement, the presence of ventricular blood, and the duration of blood clearance in the basal cisterns. The model performance was promising, with an R2 of 33% (20% after bootstrapping), the calibration plot was adequate, the Hosmer-Lemeshow test result was not significant, and the c-statistic was 0.85 (0.84 as assessed after bootstrapping) indicating a good discriminating prognostic model. CONCLUSIONS: Our prognostic model could help identify patients requiring permanent CSF diversion after aSAH, although additional modification and external validation are needed. Interventions aimed at accelerating the clearance of blood in the basal cisterns might have the potential to prevent the development of chronic hydrocephalus after aSAH.

Natural History of De Novo Aneurysm Formation in Patients with Treated Aneurysmatic Subarachnoid Hemorrhage: A Ten-Year Follow-Up.

BACKGROUND: De novo aneurysm formation after completely occluded aneurysms via clipping or coiling has not been well studied. Although known to occur several years after initial aneurysm management, the natural history of de novo aneurysms is obscure. We investigated the formation of new aneurysms in patients who had previously undergone treatment of intracranial aneurysms. METHODS: In a retrospective, single-institutional series, eligible patients who had undergone treatment of ruptured cerebral aneurysms from 2000 to 2011 were included. The primary outcome measure was the development of de novo aneurysms during long-term follow-up. RESULTS: Overall, 130 patients (63% women) who had undergone microsurgical clipping (n = 63; 48.5%) or endovascular coiling (n = 67%; 51.5%) for ruptured aneurysms were included. The average follow-up time for our cohort was 10 ± 2.7 years. De novo aneurysms occurred in 10 of 130 patients (7.7%), with a mean time of 7.9 years for aneurysm detection. No association between the formation of de novo aneurysms and the location of the treated aneurysms, smoking status, hypertension, age, or gender was found. Follow-up imaging studies were performed every 2 years. De novo aneurysms had formed in 2 patients within 2-5 years, 7 patients after 5-10 years, and 1 patient after 10 years of follow-up. In 2 of 10 patients, the de novo aneurysm had ruptured and led to subarachnoid haemorrhage. CONCLUSION: The rate of de novo aneurysm occurrence was 7.6%, with a mean time to development of 7.9 years. This underscores the significance of long-term monitoring of patients with intracranial aneurysms. In our series, most new aneurysms had occurred after 5 years of follow-up.

Anatomical evaluation of intracranial aneurysm rupture risk in patients with multiple aneurysms.

In patients with aneurysmal subarachnoid hemorrhage (aSAH) and multiple aneurysms, there is a need to objectively identify the ruptured aneurysm. Additionally, studying the intra-individual rupture risk of multiple aneurysms eliminates extrinsic risk factors and allows a focus on anatomical factors, which could be extrapolated to patients with single aneurysms too. Retrospective bi-center study (Department of Neurosurgery of the University Hospital Duesseldorf and Bern) on patients with multiple aneurysms and subarachnoid hemorrhage caused by the rupture of one of them. Parameters investigated were height, width, neck, shape, inflow angle, diameter of the proximal and distal arteries, width/neck ratio, height/width ratio, height/neck ratio, and localization. Statistical analysis and logistic regressions were performed by the R program, version 3.4.3. N = 186 patients with aSAH and multiple aneurysms were treated in either department from 2008 to 2016 (Bern: 2008-2016, 725 patients and 100 multiple aneurysms, Duesseldorf: 2012-2016, 355 patients, 86 multiple aneurysms). The mean age was 57 years. N = 119 patients had 2 aneurysms, N = 52 patients had 3 aneurysms, N = 14 had 4 aneurysms and N = 1 had 5 aneurysms. Eighty-four percent of ruptured aneurysms were significantly larger than the largest unruptured. Multilobularity of ruptured aneurysms was significantly higher than in unruptured. Metric variables describing the geometry (height, width, etc.) and shape are the most predictive for rupture. One or two of them alone are already reliable predictors. Ratios are completely redundant in saccular aneurysms.

Aneurysm wall enhancement in black blood MRI correlates with aneurysm size. Black blood MRI could serve as an objective criterion of aneurysm stability in near future.

The increasing number of incidental intracranial aneurysms creates a dilemma of which aneurysms to treat and which to observe. Clinical scoring systems consider risk factors for aneurysm rupture however objective parameters for assessment of aneurysms stability are needed. We retrospectively analysed contrast enhancing behaviour of un-ruptured aneurysms in the black blood magnetic resonance imaging (MRI) in N=71 patients with 90 aneurysms and assessed correlation between aneurysm wall contrast enhancement (AWCE) and aneurysm anatomy and clinical scoring systems. AWCE is associated with aneurysm height and height to width ratio in ICA aneurysms. AWCE is correlated to larger aneurysms in every anatomical location evaluated. However the mean size of the contrast enhancing aneurysms is significantly different between anatomical localizations indicating separate analyses for every artery. Clinical scoring systems like PHASES and UIATS correlate positively with AWCE in black blood MRI. MRI aneurysm wall contrast enhancement is a positive predictor for aneurysm instability and should be routinely assessed in follow up of incidental aneurysms. Aneurysms smaller than 7 mm with AWCE should be followed closely with focus on growth, as they may be prone to growth and rupture.