Seizure risk with AVM treatment or conservative management:Prospective, population-based study

OBJECTIVES: To compare the risk of epileptic seizures in adults during conservative management or following invasive treatment for a brain arteriovenous malformation (AVM). METHODS: We used annual general practitioner follow-up, patient questionnaires, and medical records surveillance to quantify the 5-year risk of seizures and the chances of achieving 2-year seizure freedom for adults undergoing AVM treatment compared to adults managed conservatively in a prospective, population-based observational study of adults in Scotland, newly diagnosed with an AVM in 1999–2003. RESULTS: We identified 229 adults with a new diagnosis of an AVM, of whom two-thirds received AVM treatment (154/229; 67%) during 1,862 person-years of follow-up (median completeness of follow-up 97%). There was no significant difference in the proportions with a first or recurrent seizure over 5 years following AVM treatment, compared to the first 5 years following clinical presentation in conservatively managed adults, in analyses stratified by mode of presentation (intracerebral hemorrhage, 35% vs 26%, p = 0.5; seizure, 67% vs 72%, p = 0.6; incidental, 21% vs 10%, p = 0.4). For patients with epilepsy, the chances of achieving 2-year seizure freedom during 5-year follow-up were similar following AVM treatment (n = 39; 52%, 95% confidence interval [CI] 36% to 68%) or conservative management (n = 21; 57%, 95% CI 35% to 79%; p = 0.7). CONCLUSIONS: In this observational study, there was no difference in the 5-year risk of seizures with AVM treatment or conservative management, irrespective of whether the AVM had presented with hemorrhage or epileptic seizures

Identification of a human olfactory ensheathing cell that can effect transplant-mediated remyelination of demyelinated CNS axons

The olfactory ensheathing cell (OEC) has attracted much interest recently because of its potential for transplantation-based therapy of CNS disease. Rat OECs are able to remyelinate demyelinated axons and support regeneration of damaged axons. Although OECs can be grown readily from the rat, a macrosmatic species, it has been uncertain whether it would be similarly straightforward to obtain these cells from the human, a microsmatic species with a relatively poorly developed olfactory system. In this study, we have identified a human OEC which shares many properties with its rat counterpart, including expression of the low-affinity nerve growth factor receptor (L-NGFr) and similar growth factor requirements. Purified populations of human OECs obtained by selection with L-NGFr antibodies have extremely high viability in tissue culture, and are capable of remyelinating persistently demyelinated CNS axons following transplantation into experimentally induced demyelinating lesions in the rat spinal cord. Thus, the human OEC represents an important new cell for the development of transplant therapy of CNS diseases

Outcome after surgical or conservative management of cerebral cavernous malformations

ABSTRACT Objective: There have been few comparative studies of microsurgical excision vs conservative management of cerebral cavernous malformations (CCM) and none of them has reliably demonstrated a statistically and clinically significant difference. Methods: We conducted a prospective, population-based study to identify and independently validate definite CCM diagnoses first made in 1999-2003 in Scottish adult residents. We used multiple sources of prospective follow-up to assess adults' dependence and to identify and independently validate outcome events. We used univariate and multivariable survival analyses to test the influence of CCM excision on outcome, adjusted for prognostic factors and baseline imbalances. Results: Of 134 adults, 25 underwent CCM excision; these adults were younger (34 vs 43 years at diagnosis, p 5 0.004) and more likely to present with symptomatic intracranial hemorrhage or focal neurologic deficit than adults managed conservatively (48% vs 26%; odds ratio 2.7, 95% confidence interval [CI] 1.1-6.5). During 5 years of follow-up, CCM excision was associated with a deterioration to an Oxford Handicap Scale score 2-6 sustained over at least 2 successive years (adjusted hazard ratio [HR] 2.2, 95% CI 1.1-4.3) and the occurrence of symptomatic intracranial hemorrhage or new focal neurologic deficit (adjusted HR 3.6, 95% CI 1.3-10.0). Conclusions: CCM excision was associated with worse outcomes over 5 years compared to conservative management. Long-term follow-up will determine whether this difference is sustained over patients' lifetimes. Meanwhile, a randomized controlled trial appears justified. Classification of evidence: This study provides Class III evidence that CCM excision worsens shortterm disability scores and increases the risk of symptomatic intracranial hemorrhage and new focal neurologic deficits

Untreated clinical course of cerebral cavernous malformations:a prospective, population-based cohort study

SummaryBackgroundCerebral cavernous malformations (CCMs) are prone to bleeding but the risk of intracranial haemorrhage and focal neurological deficits, and the factors that might predict their occurrence, are unclear. We aimed to quantify these risks and investigate whether they are affected by sex and CCM location.MethodsWe undertook a population-based study using multiple overlapping sources of case ascertainment (including a Scotland-wide collaboration of neurologists, neurosurgeons, stroke physicians, radiologists, and pathologists, as well as searches of registers of hospital discharges and death certificates) to identify definite CCM diagnoses first made in Scottish residents between 1999 and 2003, which study neuroradiologists independently validated. We used multiple sources of prospective follow-up both to identify outcome events (which were assessed by use of brain imaging, by investigators masked to potential predictive factors) and to assess adults' dependence. The primary outcome was a composite of intracranial haemorrhage or focal neurological deficits (not including epileptic seizure) that were definitely or possibly related to CCM.Findings139 adults had at least one definite CCM and 134 were alive at initial presentation. During 1177 person-years of follow-up (completeness 97%), for intracranial haemorrhage alone the 5-year risk of a first haemorrhage was lower than the risk of recurrent haemorrhage (2·4%, 95% CI 0·0–5·7 vs 29·5%, 4·1–55·0; p<0·0001). For the primary outcome, the 5-year risk of a first event was lower than the risk of recurrence (9·3%, 3·1–15·4 vs 42·4%, 26·8–58·0; p<0·0001). The annual risk of recurrence of the primary outcome declined from 19·8% (95% CI 6·1–33·4) in year 1 to 5·0% (0·0–14·8) in year 5 and was higher for women than men (p=0·01) but not for adults with brainstem CCMs versus CCMs in other locations (p=0·17).InterpretationThe risk of recurrent intracranial haemorrhage or focal neurological deficit from a CCM is greater than the risk of a first event, is greater for women than for men, and declines over 5 years. This information can be used in clinical practice, but further work is needed to quantify risks precisely in the long term and to understand why women are at greater risk of recurrence than men.FundingUK Medical Research Council, Chief Scientist Office of the Scottish Government, and UK Stroke Association

Procedures performed during neurosurgery residency in Europe

International audienceAbstract Background In a previous article ( 10.1007/s00701-019-03888-3 ), preliminary results of a survey, aiming to shed light on the number of surgical procedures performed and assisted during neurosurgery residency in Europe were reported. We here present the final results and extend the analyses. Methods Board-certified neurosurgeons of European Association of Neurosurgical Societies (EANS) member countries were asked to review their residency case logs and participate in a 31-question electronic survey (SurveyMonkey Inc., San Mateo, CA). The responses received between April 25, 2018, and April 25, 2020, were considered. We excluded responses that were incomplete, from non-EANS member countries, or from respondents that have not yet completed their residency. Results Of 430 responses, 168 were considered for analysis after checking in- and exclusion criteria. Survey responders had a mean age of 42.7 ± 8.8 years, and 88.8% were male. Responses mainly came from surgeons employed at university/teaching hospitals (85.1%) in Germany (22.0%), France (12.5%), the United Kingdom (UK; 8.3%), Switzerland (7.7%), and Greece (7.1%). Most responders graduated in the years between 2011 and 2019 (57.7%). Thirty-eight responders (22.6%) graduated before and 130 responders (77.4%) after the European WTD 2003/88/EC came into effect. The mean number of surgical procedures performed independently, supervised or assisted throughout residency was 540 (95% CI 424–657), 482 (95% CI 398–568), and 579 (95% CI 441–717), respectively. Detailed numbers for cranial, spinal, adult, and pediatric subgroups are presented in the article. There was an annual decrease of about 33 cases in total caseload between 1976 and 2019 (coeff. − 33, 95% CI − 62 to − 4, p = 0.025). Variables associated with lesser total caseload during residency were training abroad (1210 vs. 1747, p = 0.083) and female sex by trend (947 vs. 1671, p = 0.111), whereas case numbers were comparable across the EANS countries ( p = 0.443). Conclusion The final results of this survey largely confirm the previously reported numbers. They provide an opportunity for current trainees to compare their own case logs with. Again, we confirm a significant decline in surgical exposure during training between 1976 and 2019. In addition, the current analysis reveals that female sex and training abroad may be variables associated with lesser case numbers during residency