Patrick A. Brouwer

The use of 4D-CTA in the diagnostic work-up of brain arteriovenous malformations

IntroductionWe aimed to evaluate the use of time-resolved whole-head CT angiography (4D-CTA) in patients with an untreated arteriovenous malformation of the brain (bAVM), as demonstrated by catheter angiography (DSA).MethodsSeventeen patients with a DSA-proven bAVM were enrolled. These were subjected to 4D-CTA imaging using a 320 detector row CT scanner. Using a standardized scoring sheet, all studies were analyzed by a panel of three readers. This panel was blind to the DSA results at the time of reading the 4D-CTA.Results4D-CTA detected all bAVMs. With regard to the Spetzler–Martin grade, 4D-CTA disagreed with DSA in only one case, where deep venous drainage was missed. Further discrepancies between 4D-CTA and DSA analyses included underestimation of the nidus size in small lesions (four cases), misinterpretation of a feeding vessel (one case), misinterpretation of indirect feeding through pial collaterals (three cases) and oversight of mild arterial enlargement (two cases). 4D-CTA correctly distinguished low-flow from high-flow lesions and detected dural/transosseous feeding (one case), venous narrowing (one case) and venous pouches (nine cases).ConclusionIn this series, 4D-CTA was able to detect all bAVMs. Although some angioarchitectural details were missed or misinterpreted when compared to DSA, 4D-CTA evaluation was sufficiently accurate to diagnose the shunt and classify it. Moreover, 4D-CTA adds cross-sectional imaging and perfusion maps, helpful in treatment planning. 4D-CTA appears to be a valuable new adjunct in the non-invasive diagnostic work-up of bAVMs and their follow-up when managed conservatively.

Percutaneous laser disc decompression versus conventional microdiscectomy in sciatica: a randomized controlled trial.

BACKGROUND CONTEXTnPercutaneous laser disc decompression (PLDD) is a minimally invasive treatment for lumbar disc herniation, with Food and Drug Administration approval since 1991. However, no randomized trial comparing PLDD to conventional treatment has been performed.nnnPURPOSEnIn this trial, we assessed the effectiveness of a strategy of PLDD as compared with conventional surgery.nnnSTUDY DESIGN/SETTINGnThis randomized prospective trial with a noninferiority design was carried out in two academic and six teaching hospitals in the Netherlands according to an intent-to-treat protocol with full institutional review board approval.nnnPATIENT SAMPLEnOne hundred fifteen eligible surgical candidates, with sciatica from a disc herniation smaller than one-third of the spinal canal, were included.nnnOUTCOME MEASURESnThe main outcome measures for this trial were the Roland-Morris Disability Questionnaire for sciatica, visual analog scores for back and leg pain, and the patients report of perceived recovery.nnnMETHODSnPatients were randomly allocated to PLDD (n=57) or conventional surgery (n=58). Blinding was impossible because of the nature of the interventions. This study was funded by the Healthcare Insurance Board of the Netherlands.nnnRESULTSnThe primary outcome, Roland-Morris Disability Questionnaire, showed noninferiority of PLDD at 8 (-0.1; [95% confidence interval (CI), -2.3 to 2.1]) and 52 weeks (-1.1; 95% CI, -3.4 to 1.1) compared with conventional surgery. There was, however, a higher speed of recovery in favor of conventional surgery (hazard ratio, 0.64 [95% CI, 0.42-0.97]). The number of reoperations was significantly less in the conventional surgery group (38% vs. 16%). Overall, a strategy of PLDD, with delayed surgery if needed, resulted in noninferior outcomes at 1 year.nnnCONCLUSIONSnAt 1 year, a strategy of PLDD, followed by surgery if needed, resulted in noninferior outcomes compared with surgery.

Effectiveness of percutaneous laser disc decompression versus conventional open discectomy in the treatment of lumbar disc herniation; design of a prospective randomized controlled trial

BackgroundThe usual surgical treatment of refractory sciatica caused by lumbar disc herniation, is open discectomy. Minimally invasive procedures, including percutaneous therapies under local anesthesia, are increasingly gaining attention. One of these treatments is Percutaneous Laser Disc Decompression (PLDD). This treatment can be carried out in an outpatient setting and swift recovery and return to daily routine are suggested. Thus far, no randomized trial into cost-effectiveness of PLDD versus standard surgical procedure has been performed. We present the design of a randomized controlled trial, studying the cost-effectiveness of PLDD versus conventional open discectomy in patients with sciatica from lumbar disc herniation.Methods/designThe study is a randomized prospective multi-center trial, in which two treatment strategies are compared in a parallel group design. Patients (age 18–70 years) visiting the neurosurgery department of the participating hospitals, are considered for inclusion in the trial when sciatica due to lumbar disc herniation has lasted more than 8 weeks. Patients with disc herniation smaller than 1/3 of the spinal canal diameter, without concomitant lateral recess stenosis or sequestration, are eligible for participation, and are randomized into one of two treatment arms; either Percutaneous Laser Disc Decompression or conventional discectomy. The functional outcome of the patient, as assessed by the Roland Disability Questionnaire for Sciatica at 8 weeks and 1 year after treatment, is the primary outcome measure. The secondary outcome parameters are recovery as perceived by the patient, leg and back pain, incidence of re-intervention, complications, quality of life, medical consumption, absence of work and secondary costs.DiscussionOpen discectomy is still considered to be the golden standard in the surgical treatment of lumbar disc herniation. Whether Percutaneous Laser Disc Decompression has at least as much efficacy as the standard surgical procedure, and is more cost-effective, will be determined by this trial.Trial registrationCurrent Controlled Trials ISRCTN25884790.

Experimental basis of percutaneous laser disc decompression (PLDD): a review of literature.

Percutaneous laser disc decompression (PLDD) is one of the so-called “minimally invasive” treatment modalities for lumbar disc herniation. The treatment is performed percutaneously; therefore, morbidity and convalescence period are postulated to be less than for conventional surgery. Because of the minimally invasive nature and the fact that return to work is usually possible within a few days after treatment, PLDD appears to be an interesting alternative to conventional surgery. However, PLDD still encounters a considerable amount of skepticism. Opponents usually dismiss PLDD as being an experimental treatment with unproven efficacy, while those advocating the use of PLDD tend to present it as some kind of miracle treatment. While well-designed clinical trials focusing primarily on the efficacy of PLDD are scarce [1], the amount of preclinical studies investigating the technical and biophysical aspects of PLDD has been growing steadily since its introduction in the late 1980s. By grouping the results of these preclinical trials, this review attempts to provide a comprehensive basis for further clinical research.

Prevalence of Brain Arteriovenous Malformations in First-Degree Relatives of Patients With a Brain Arteriovenous Malformation

Background and Purpose— It is uncertain whether familial occurrence of brain arteriovenous malformations (BAVMs) represents coincidental aggregation or a shared familial risk factor. We aimed to compare the prevalence of BAVMs in first-degree relatives (FDRs) of patients with BAVM and the prevalence in the general population. Methods— We sent a postal questionnaire to 682 patients diagnosed with a BAVM in 1 of 4 university hospitals to retrieve information about the occurrence of BAVMs among their FDRs. We calculated a prevalence ratio using the BAVM prevalence among FDRs and the prevalence from a Scottish population-based study (93 per 628 788 adults). A prevalence ratio of ≥9 with a lower limit of the 95% confidence interval of 3 was considered indicative of a shared familial risk factor. Results— Informed consent was given by 460 (67%) patients, who had 2992 FDRs. We identified 3 patients with a FDR with a BAVM, yielding a prevalence ratio of 6.8 (95% CI, 2.2–21). Conclusions— The prevalence of BAVMs in FDRs of patients with a BAVM was increased but did not meet our prespecified criterion for a shared familial risk factor. In combination with the low absolute risk of a BAVM in FDRs, our results do not support screening of FDRs for BAVMs.

Coil-treated Aneurysms: Decision Making Regarding Additional Treatment Based on Findings of MR Angiography and Intraarterial DSA

PURPOSEnTo assess whether magnetic resonance (MR) angiography can be used as a noninvasive alternative to intraarterial digital subtraction angiography (DSA) to indicate additional treatment in the follow-up of patients with coil-treated intracranial aneurysms.nnnMATERIALS AND METHODSnThis was an ethics committee-approved multicenter study. Consecutive patients who were scheduled for follow-up intraarterial DSA after coil placement were invited for additional MR angiography after providing written informed consent. Interventional neuroradiologists gave treatment advice (additional treatment, extended follow-up imaging, or discharge from follow-up) for each imaging modality. Agreement between treatment advices based on intraarterial DSA and MR angiographic findings and interobserver agreement were assessed with weighted κ statistics.nnnRESULTSnAgreement between intraarterial DSA- and MR angiography-based treatment recommendations was substantial (κ = 0.73; 95% confidence interval [CI]: 0.66, 0.80). In 34 of the 310 patients (11%), the advice was additional treatment based on findings of both modalities. In six patients (2%), the advice based on intraarterial DSA findings was additional treatment, while that based on MR angiographic findings was extended follow-up imaging; therefore, none of these patients were discharged from follow-up on the basis of MR angiographic findings. In six other patients (2%), the advice based on MR angiographic findings was additional treatment, while that based on intraarterial DSA findings was extended follow-up imaging (four patients), discharge from follow-up (one patient), and noninterpretable DSA (one patient). Extended follow-up imaging was suggested for 37 patients (12%) after intraarterial DSA and for 49 patients (16%) after MR angiography (difference: 4%; 95% CI: -0.6%, 8.4%). Interobserver agreement was substantial for intraarterial DSA (κ = 0.73; 95% CI: 0.64, 0.82) and moderate for MR angiography (κ = 0.53; 95% CI: 0.36, 0.70).nnnCONCLUSIONnThe overall proportion of patients advised to undergo additional treatment is similar based on intraarterial DSA and MR angiographic findings, with only few individual discrepancies. MR angiography can therefore be used for therapeutic decision making in the follow-up of patients with coil-treated aneurysms.nnnSUPPLEMENTAL MATERIALnhttp://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.12112608/-/DC1.

Relative risk of hemorrhage during pregnancy in patients with brain arteriovenous malformations

Background It is unclear whether the risk of bleeding from brain arteriovenous malformations is higher during pregnancy, delivery, or puerperium. We compared occurrence of brain arteriovenous malformation hemorrhage in women during this period with occurrence of hemorrhage outside this period during their fertile years. Methods We included all women with ruptured brain arteriovenous malformations (16–41 years) from a retrospective database of patients with brain arteriovenous malformations in four Dutch university hospitals (nu2009=u200995) and from the population-based Scottish Audit of Intracranial Vascular Malformations (nu2009=u200944). We estimated the relative rate of brain arteriovenous malformation rupture (before any treatment) during exposed time (pregnancy, delivery, puerperium) versus non-exposed time during fertile years, using the case-crossover design as primary analysis, and the self-controlled case-series design as secondary analysis. Results In 17 of 95 Dutch women and in 3 of 44 Scottish women, hemorrhages occurred while pregnant; none occurred during delivery or puerperium. In Dutch women, the relative rate of brain arteriovenous malformation rupture during pregnancy, delivery, or puerperium was 6.8 (95% confidence interval 3.6–13) according to the case-crossover method and 7.1 (95% confidence interval 3.4–13) using the self-controlled case-series method. In Scottish women, the relative rate was 1.3 (95% confidence interval 0.39–4.1) using the case-crossover method and 1.7 (95% confidence interval 0.0–4.4) according to the self-controlled case-series method. Because of limited overlap of confidence intervals, we refrained from pooling the cohorts. Conclusions Case-crossover and self-controlled case series analyses reveal an increase in relative rate of brain arteriovenous malformation rupture during pregnancy in the Dutch cohort but not in the Scottish cohort. Since point estimates varied between both cohorts and numbers are relatively small, the clinical implications of our findings are uncertain.

Parental age and the occurrence of sporadic brain arteriovenous malformations

Dear editor, The pathogenesis of sporadic brain arteriovenous malformations (BAVMs) remains unclear, but accumulating evidence suggests a genetic susceptibility. Within the context of genetic susceptibility, de novo mutations arising from the germline may play a role. As parental ageing is a risk factor for transmission of de novo mutations, we investigated whether higher parental age at delivery is associated with the occurrence of BAVMs in the offspring. We approached a cohort of 682 BAVM patients, who were seen between 1990 and 2006 at one of four university hospitals in the Netherlands, with a postal questionnaire to retrieve the dates of birth of their parents. We compared parental age at delivery of patients with a BAVM, with population means of parental age matched for sex, birth order, and year of birth using the Mann–Whitney U test. Because maternal age of the controls for patients born before 1950 was lacking, we extrapolated data from more recent years, and performed a sensitivity analysis excluding this subgroup to address the potential influence on the results. Paternal age of the control population was unavailable before 1996. Based on available data on the period after 1995, we assumed that fathers were on average three years older than mothers. We obtained responses from 460 (67%) patients. Baseline characteristics, including the year of birth, did not differ between responders and non-responders. We found no significant difference in both maternal and paternal age at the time of delivery between BAVM patients and the matched control population (Table 1). In addition, the sensitivity analysis excluding the patients born before 1950, yielded essentially the same results. In conclusion, parental age at delivery did not differ between patients with a BAVM and the general population. Our results do not support the hypothesis that de novo mutations arising from the germline underlie BAVM pathogenesis.

Nontraumatic Neuroemergencies - I

As nontraumatic neuroemergencies comprise a large number of diseases, it is virtually impossible to provide a complete overview in this syllabus text. Therefore, the focus is directed to the most frequent vascular causes, which are illustrated with their (un-)usual presentation, (un-)characteristic imaging findings, and available treatment options.

Diagnostiek en behandeling van intracraniële aneurysmata

Bij de westerse populatie komt een subarachnoidale bloeding als gevolg van een geruptureerd intracranieel aneurysma voor bij ongeveer 6 tot 8 per 100.000 inwoners. In sommige landen, waaronder Finland en Japan is dit percentage zelfs 20 per 100.000. Zestig procent van de patienten die zich presenteren met een SAB is vrouw.