Microsurgical and endovascular treatment of un-ruptured cerebral aneurysms by European hybrid neurosurgeons to balance surgical skills and medical staff management.

BACKGROUND: In Europe, aneurysm treatment performed by dually trained neurosurgeons is extremely scarce. We provide outcome data for un-ruptured aneurysm patients treated at a European hybrid center to prove that hybrid neurosurgeons achieve clinical and angiographical results allowing to integrate hybrid neurosurgery into routine aneurysm treatment. This will not only help to maintain neurovascular microsurgical skills but will influence staff costs in related hospitals. METHODS: We retrospectively analyzed all consecutively treated un-ruptured aneurysm patients between 2000 and 2016. The decision-making took into account the pros and cons of both modalities and considered patient and aneurysm characteristics. Clinical outcome was assessed by the modified Rankin scale (mRS). Occlusion rates were stratified into grade I for 100%, grade II for 99-90%, and grade III for <90% occlusion. To account for the introduction of stents, two treatment periods (p1, 2000 to 2008; p2, 2009 to 2016) were defined. RESULTS: The study population consisted of 274 patients (median age 55 years) harboring 338 un-ruptured aneurysms. Microsurgery (MS) was performed in 51.8% and endovascular therapy (EVT) in 43.1%; 5.1% required combined treatment. Overall, 93% showed a favorable clinical outcome (mRS 0-2), 94.3% after MS and 91.5% after EVT. Grade I aneurysm occlusion was achieved in 82.6% patients, 91.9% after MS and 72.9% after EVT. Procedure-related complications occurred after MS in 5.6% and after EVT in 4.4% patients. Mortality was recorded for five (1.8%) patients, one patient after MS and four after EVT. For the EVT cohort, significant improvement from p1 to p2 was seen with clinical outcomes (P=0.030, RR = 0.905, CI: 0.8351-0.9802) and occlusion rates (P=0.039, RR = 0.6790, CI: 0.499-0.923). CONCLUSION: Hybrid neurosurgeons achieve qualified clinical and angiographic results. Dual training will allow to maintain neurovascular caseloads and preserve future aneurysm treatment within neurosurgery. Furthermore economic benefits could be observed in hospital management.

Ventriculoatrial Shunts in Adults, Incidence of Infection, and Significant Risk Factors: A Single-Center Experience.

BACKGROUND: In recent years, the number of ventriculoatrial (VA) shunt insertions has decreased worldwide, the major cause being the risk of shunt infection. VA shunts remain as an alternative option to ventriculoperitoneal shunts. We describe our 10-year experience with VA shunts by analyzing the incidence of shunt infections and predisposing cofactors. METHODS: During a median follow-up of 15.3 months, 259 shunt insertions, performed on 255 patients, were analyzed. The infection rate was calculated and the predisposing cofactors age, gender, cause of the hydrocephalus, previous external ventricle drainage, antibiotic-impregnated catheters, the number of revisions, the educational level of the surgeons, and the duration of the operations were analyzed. Two observation times were stratified. RESULTS: We found overall infections in 18 patients (7.1%), 16 deep infections (6.3%) including 1 shunt nephritis (0.4%) and 2 superficial infections (0.8%). Wound dehiscence occurred in 17 patients (6. 6%). Analyzing follow-up time, the infection rate was 3.65% (95% confidence interval, 0.9%-5.9%) at survival time 1, 3.38% (95% confidence interval, 1.1%-6.2%) at survival time 2. In the first 6 months, 95% of patients were free of infection. Only the number of revision procedures was associated with the number of infections (P value < 0.0005). CONCLUSIONS: In our patient cohort, the infection rate related to VA shunt insertion is low; the only statistically significant risk factor was the number of revisions. If the VA shunt is applied following a standardized protocol, the infection risk does not represent an argument for reluctance towards the VA draining concept.

The efficacy of dexamethasone on reduction in the reoperation rate of chronic subdural hematoma--the DRESH study: straightforward study protocol for a randomized controlled trial.

BACKGROUND: Chronic subdural hematoma (cSDH) is a common neurosurgical disease. It is often considered to be a rather benign entity. In spite of well established surgical procedures cSDH is complicated by a recurrence rate up to 30%. Since glucocorticoids have been used for treatment of cSDH in 1962 their role is still discussed controversially in lack of evident data. On the basis of the ascertained inflammation cycle in cSDH dexamethasone will be an ideal substance for a short lasting, concomitant treatment protocol. OBJECTIVE: to test the efficacy of dexamethasone on reduction inthe reoperation rate of cSDH. METHODS/DESIGN: The study is designed as a double-blind randomized placebo-controlled trial 820 patients who are operated for cSDH and from the age of 25 years are included after obtaining informed consent. They are randomized for administration of dexamethasone (16-16-12-12-8-4 mg/d) or placebo (maltodextrin) during the first 48 hours after surgery. The type I error is 5% and the type II error is 20%. The primary endpoint is the reoperation within 12 weeks postoperative. DISCUSSION: This study tests whether dexamethasone administered over 6 days is a safe and potent agent in relapse prevention for evacuated cSDH. TRIAL REGISTRATION: EudraCT 201100354442.

Histological analysis of clipped human intracranial aneurysms and parent arteries with short-term follow-up.

BACKGROUND: Surgical clipping of intracranial aneurysms is the gold standard for the prevention of rupture. However, the biological processes that occur following clipping are poorly understood. To better understand these effects, retrieved and clipped human intracranial aneurysms were examined histologically. METHODS: At autopsy, 17 aneurysms from 10 patients were retrieved 3-21 days after clipping. The tissues were embedded in paraffin, and microtome sections were stained using hematoxylin-eosin and Movat pentachrome. Using light microscopy, clip placement relative to the internal elastic lamina of the parent artery, endothelialization of the aneurysm neck, thrombus organization inside the aneurysm sac, inflammation in the sac, wall, and parent artery, and atherosclerotic changes were determined. RESULTS: Despite complete reconstruction of the artery with the clip, diseased vessel wall was frequently observed outside the clip. By 10 days postsurgery, the beginnings of endothelialization and neointima formation were observed at the neck. However, the neck coverage was variable and incomplete at these early time points. Thrombus organization inside the aneurysm sac was rarely observed, and inflammatory cells were not present inside the aneurysm sac. Inflammatory cells were commonly observed in the aneurysm wall, and atherosclerotic change was present in each sample. CONCLUSIONS: Complete aneurysm exclusion and apposition of healthy arterial wall occurred infrequently in our series. Endothelialization and neointima formation at the aneurysm neck take some time to complete and are often incomplete. The effectiveness of aneurysm clipping is related to the mechanics of aneurysm exclusion rather than the processes of endothelialization and neointima formation. SUMMARY: Complete aneurysm exclusion and apposition of healthy arterial wall occurred infrequently in our series. Endothelialization and neointima formation at the aneurysm neck take some time to complete and are often incomplete. The effectiveness of aneurysm clipping is related to the mechanics of aneurysm exclusion rather than the processes of endothelialization and neointima formation.

Histomorphology of thrombus organization, neointima formation, and foreign body response in retrieved human aneurysms treated with hydrocoil devices.

Biological processes, such as thrombus organization, endothelialization, and foreign body response, that occur following embolization of intracranial aneurysms are poorly understood. We examined 13 human aneurysms (retrieved at autopsy 1-74 days postembolization) treated with hybrid hydrogel-platinum coil devices and platinum coils. The specimens were embedded in methyl methacrylate and ground sections were surface stained. Using light microscopy, thrombus organization in the sac, endothelialization of the neck, and foreign body response to the embolic devices were determined. The area percentages of the sac occupied by embolic devices and unorganized thrombus were quantified using image analysis. Thrombus organization increased over time, but was incomplete up to 74 days post-treatment. Neointima formation had started at 5 days upon dense fibrin depositions and progressed to form a new vessel wall at 74 days. The foreign body response to the hydrogel was characterized by mononuclear macrophages, while platinum coils were surrounded by multinuclear foreign body giant cells. Histometric aneurysm occlusion ranged from 89 to 100% and embolic devices occupied 31-64% of the aneurysm sac. These findings showed that the hydrogel-based devices occupied a large percentage of the aneurysm sac, provided a framework for thrombus organization to occur, and elicited less severe foreign body response than platinum coils.

The Austrian Brain Tumour Registry: a cooperative way to establish a population-based brain tumour registry.

In Austria, registration of malignant brain tumours is legally mandatory, whereas benign and borderline tumours are not reported. The Austrian Brain Tumour Registry (ABTR) was initiated under the auspices of the Austrian Society of Neuropathology for the registration of malignant and non-malignant brain tumours. All Austrian neuropathology units involved in brain tumour diagnostics contribute data on primary brain tumours. Non-microscopically verified cases are added by the Austrian National Cancer Registry to ensure a population-based dataset. In 2005, we registered a total of 1,688 newly diagnosed primary brain tumours in a population of 8.2 million inhabitants with an overall age-adjusted incidence rate of 18.1/100,000 person-years. Non-malignant cases constituted 866 cases (51.3%). The incidence rate was higher in females (18.6/100,000) as compared to males (17.8/100,000), while 95/1,688 (5.6%) cases were diagnosed in children (<18 years). The most common histology was meningioma (n = 504, 29.9%) followed by glioblastoma (n = 340, 20.1%) and pituitary adenoma (n = 151, 8.9%). Comparison with the Central Brain Tumor Registry of the United States (CBTRUS) database showed high congruency of findings. The ABTR model led by neuropathologists in collaboration with epidemiologists and the Austrian National Cancer Registry presents a cooperative way to establish a population-based brain tumour registry with high quality data. This setting links cancer registration to the mission of medical practice and research as defined by the World Medical Association in the Declaration of Helsinki. The continued operation of ABTR will aid in monitoring changes in incidence and in identifying regional disease clusters or geographic variations in brain tumour morbidity/mortality.

Comparison of experimental aneurysms embolized with second-generation embolic devices and platinum coils.

PURPOSE: The purpose of the study was to compare the performance of second-generation embolic devices with that of platinum coils in experimental aneurysms. METHODS: Microsurgically constructed bifurcation aneurysms in rabbits were embolized with platinum coils (n = 7), HydroCoils 10 (n = 10), HydroSoft (n = 14) or Cerecyte (n = 6) devices. After 1 month, angiographic occlusion was scored and the aneurysms were histologically evaluated by light microscopy. Continuous and ordinal results were compared using ANOVA/Tukey-Kramer HSD and chi(2) tests respectively. RESULTS: Angiographic occlusion at follow-up was increased in the HydroCoil and HydroSoft groups and decreased in the platinum coil and Cerecyte groups. Fibrovascular tissue was observed in the sac of the Cerecyte group, while mixtures of fibrovascular tissue and fibrinous thrombus were observed in the other three groups. The inflammatory response and endothelialization of the neck were similar in all groups. CONCLUSIONS: Expansile hydrogel devices have led to increased progressive occlusion, while degradable polymer devices led to an increased rate of thrombus organization compared with platinum coils.

Long-term outcome of a multidisciplinary concept of spinal dural arteriovenous fistulae treatment.

INTRODUCTION: The optimal treatment of spinal dural arteriovenous fistulae (SDAVF) remains controversial and long-term follow-up data, especially data from multidisciplinary treatment, are rarely available. Thus, long-term outcomes following a multidisciplinary approach to the treatment of SDAVF were investigated. METHODS: The investigation included 26 patients with SDAVF treated at the authors' department over a 15-year period including a follow-up of more than 2 years. The treatment strategy when occlusion of the draining vein could be achieved was to embolize the fistula with Histoacryl, with surgery reserved for those patients unsuitable for embolization. Posttreatment angiography followed by MRI was performed in all patients. Clinical follow-up was performed using the gait and micturition Aminoff-Logue scale scores and the modified Rankin scale score. RESULTS: Embolization was performed in 19 patients (73.1%), and direct surgery in 7 patients (26.9%). Follow-up angiography (at a mean of 21.7 months) showed occlusion of the SDAVF in 24 patients (92.3%). Of the 19 embolized patients, 2 (10.5%) developed recurrence secondary to insufficient occlusion of the SDAVF draining vein, and one of these two patients underwent re-embolization and one re-operation. No negative effects of SDAVF recurrence on the final clinical outcome were identified in either patient. MRI after angiography (at a mean of 91.5 months) demonstrated occlusion of all SDAVFs. After a mean clinical follow-up of 103.4 months there was a statistically significant improvement in both the modified Rankin scale score and the Aminoff-Logue gait scale score (P < 0.05). CONCLUSION: The present multidisciplinary study showed for the first time that embolization leads to stable neuroradiological results and favourable clinical outcomes even for very long follow-up times of more than 100 months. Microsurgery remains the treatment of choice when safe embolization of the draining vein cannot be achieved.

Therapy of brain arteriovenous malformations: multimodality treatment from a balanced standpoint.

The three therapeutic modalities for arteriovenous malformation (AVM) treatment (surgery, embolization, and radiotherapy) developed in the past years with specific tools, each tool with its own qualities. Soon after the implementation of embolization for treatment of AVMs, this technique was used in combination with microsurgery; since the development of radiosurgery, treatment algorithms combining embolization with surgery and eventual subsequent radiosurgery, embolization with radiosurgery, or surgery with subsequent radiosurgery have been reported. These different combinations have been in use under the term multimodality treatment for many years, but the algorithms regarding the combination of tools, which tool has priority, and how the risk levels of each tool are assessed shows great variability among institutions. Centers with a surgical background see embolization as a technique to increase surgical feasibility and radiosurgery as a tool to complete subtotal AVM excision. Institutions with an endovascular background embolize AVMs with the aim of maximal occlusion rates and view surgery or radiosurgery as a technique to be used if the goal of total endovascular occlusion cannot be achieved. Radiosurgeons receive patients after incomplete embolization or surgical extirpation or a combination of both.

History of endovascular surgery: personal accounts of the evolution.

Endovascular therapy has continuously evolved since it was first described in 1904. It was first used as a technique to inject particles to follow the flow into vascular lesions, and from the mid-seventies on, microballoons were developed to reach targets in the arterial vascular tree. Arteriovenous malformations were approached with catheters, the tip mounted by calibrated leak balloons. The embolizing material injected was cyanoacrylate labeled with Lipiodol (Lafayette Pharmacal, Lafayette, IN), a technique that is similar to what we use today. Flow-guided microballoons placed and detached in brain aneurysms eventually became unstable, making reperfusion and rupture possible. With the introduction of guidewire-supported microcatheters, controlled navigation in the endovascular tree became possible, allowing the injection of particles, liquid embolizing agents, or free coils. In 1991, detachable coils became available and brought new therapeutic concepts. Having learned that detachable coils could not be used to treat aneurysms, which were difficult to treat surgically, the neurosurgical community accepted this new technology primarily for patients in poor condition following aneurysmal subarachnoid hemorrhage. Increased experience led to better clinical results, and Guglielmi detachable coiling therapy began to be accepted also for patients with posterior circulation aneurysms. Recent controlled trials and new technologies improving the endovascular feasibility have raised the acceptance of endovascular therapy for brain aneurysms. The elegance of the endovascular approach was an important argument for this technology from its inception, but in early years, restricted endovascular efficacy limited the efficiency of embolizations. Increasing experience and exploding new technologies have made endovascular techniques not only safer but also as effective as microsurgery. The number of vascular pathologies where microsurgery is the only option is decreasing, and training in vascular neurosurgery may become the privilege of specialized centers in the future.