Intracranial Dissecting Aneurysms Research Articles

"Pediatric Spontaneous Intracranial Dissecting Aneurysms: Impact of Ischemic and Hemorrhagic Manifestations on Endovascular Treatment Strategies - Insights from a Developing World Setting”

Pediatric spontaneous intracranial dissecting aneurysms (IDA) are rare, but systematic studies comparing hemorrhagic and ischemic presentations are lacking. This study addresses gaps in understanding their epidemiology, clinical presentation, management, and outcome. A retrospective analysis of 23 pediatric patients with nontraumatic IDA treated between July 2018 and December 2023 was conducted. Patients were divided into two groups based on presentation: hemorrhagic (n=16) and ischemic (n=7). Clinical data were analyzed, including demographics, radiological findings, treatment modalities, and outcomes. Clinical presentations varied, with limb weakness being more prevalent in hemorrhagic cases (p=0.014), while headache and seizures were more common in ischemic cases. Angiographic analysis revealed distinct patterns, with hemorrhagic cases showing more distal involvement on vessel segments with stenosis and dilatation (pearl string sign). At the same time, the ischemic group exhibited the double-lumen sign. Various treatments, including microsurgery and endovascular techniques, were utilized, with perioperative complications observed, including one mortality in a hemorrhagic case. Multiple regression analysis identified significant risk factors for perioperative complications, namely, the configuration of the dissecting aneurysm (p=0.016) and the type of presentation (p=0.0006). Long-term Glasgow Outcome Scores were comparable, but patients with hemorrhagic manifestations experienced prolonged hospital and ICU stays (p=0.001). Pediatric intracranial dissecting aneurysms, particularly hemorrhagic cases, are associated with severe neurological deficits and higher perioperative complications. Despite similar long-term outcomes, hemorrhagic cases require prolonged hospitalization, increasing treatment costs. Optimizing management strategies for pediatric ICDAs, especially those with hemorrhagic features, is essential to improve outcomes and reduce healthcare expenditures.

Abstract 166: Comparative Outcome of Intracranial Dissecting Aneurysms Treated by Endovascular and Surgical Treatment following intracranial hemorrhage

Introduction intracranial dissecting aneurysm in pediatric age group is uncommon and very few studies are available comparing outcome following endovascular and surgery. The primary objective of this study was to evaluate the clinico‐radiological characteristics of intracranial dissecting aneurysms (IDAs) in childhood and assess the treatment outcomes associated with this condition. Methods A retrospective analysis was performed on pediatric patients who received treatment for spontaneous IDAs at our institution between January 2019 and December 2023. Detailed examinations of clinical presentation, aneurysm features, treatment modalities, and patient outcomes were conducted. Results The study involved 25 pediatric patients with IDAs, with a mean age of 12.4 ± 4.9 years (range, 3–15 years), comprising 25% of all treated intracranial aneurysms in pediatric cases during the specified period. Among them, 15 (60%) were male and 10 (40%) were female. The incidence of large (≥10 mm) or giant (≥25 mm) aneurysms was 40%. Endovascular treatment was administered to 11 (44%) patients, surgical treatment to 9 (36%) patients, and 5 (20%) patients received conservative treatment. Perioperative complications occurred in 2 patients treated with endovascular and 3 patients treated surgically (p = 0.21). Out of those treated with endovascular intervention, two patients achieved full recovery with a Glasgow Outcome Scale (GOS) score of 5, and one patient treated surgically recovered with a GOS score of 4. Overall, 22 (88%) patients experienced a favorable outcome, while three (12%) had an unfavorable outcome during a mean follow‐up of 22.32 ± 7.43 months (range, 6–55 months). Conclusion Pediatric IDAs are infrequent occurrences. In this specific series, endovascular management emerged as a relatively safe and effective treatment approach for pediatric IDAs. However, continued follow‐up is essential due to the potential risk of aneurysm recurrence and de novo aneurysm formation following treatment.

Low-profile visualized intraluminal support-within-Enterprise overlapping-stent technique versus flow diversion in the treatment of intracranial vertebrobasilar trunk dissecting aneurysms.

It is necessary to explore the safety and efficacy of various endovascular treatment techniques in the treatment of patients with intracranial vertebrobasilar trunk dissecting aneurysms (VBTDAs). This study sought to compare the clinical and angiographic outcomes of patients with intracranial VBTDAs following low-profile visualized intraluminal support (LVIS)-within-Enterprise overlapping-stent technique with those of flow diversion (FD). This was a retrospective, observational, cohort study. Between January 2014 and March 2022, 9,147 patients with intracranial aneurysms were screened, and 91 patients with 95 VBTDAs who underwent LVIS-within-Enterprise overlapping-stent assisted-coiling technique or FD were included in the analysis. The primary outcome was the complete occlusion rate at the last angiographic follow-up. The secondary outcomes included adequate aneurysm occlusion, in-stent stenosis/thrombosis, general neurological complications, neurological complications within 30 days after the procedure, the mortality rate, and unfavorable outcomes. Among the 91 included patients, 55 were treated with LVIS-within-Enterprise overlapping-stent technique (the LE group) and 36 were treated with FD (the FD group). The angiography results at the median follow-up time of 8 months showed complete occlusion rates of 90.0% and 60.9% for the LE and FD groups, respectively, with an adjusted odds ratio of 5.79 (95% CI: 1.35-24.85; P=0.01). Adequate aneurysm occlusion (P=0.98), in-stent stenosis/thrombosis (P=0.46), general neurological complications (P=0.22), neurological complications within 30 days after the procedure (P=0.63), mortality rate (P=0.31), and unfavorable outcomes (P=0.07) at the last clinical follow-up did not differ significantly between the 2 groups. A significantly higher complete occlusion rate for VBTDAs was found following LVIS-within-Enterprise overlapping-stent technique as compared with FD. The 2 treatment modalities have comparable adequate occlusion rates and safety profiles.

Diagnostic Performance of High-Resolution Vessel Wall MR Imaging Combined with TOF-MRA in the Follow-up of Intracranial Vertebrobasilar Dissecting Aneurysms after Reconstructive Endovascular Treatment.

Few studies have reported the utility of high-resolution vessel wall MR imaging in the follow-up of endovascularly treated vertebrobasilar dissecting aneurysms. This study aimed to evaluate the diagnostic performance of high-resolution vessel wall MR imaging combined with TOF-MRA in the follow-up of intracranial vertebrobasilar dissecting aneurysms after reconstructive endovascular treatment. Patients with intracranial vertebrobasilar dissecting aneurysms with reconstructive endovascular treatment and followed up with TOF-MRA, high-resolution vessel wall MR imaging, and DSA were included. With DSA as the criterion standard, the diagnostic performance of TOF-MRA, high-resolution vessel wall MR imaging, and high-resolution vessel wall MR imaging combined with TOF-MRA in the evaluation of aneurysm occlusion status and parent artery patency was assessed. Visualization of the stented artery on TOF-MRA and high-resolution vessel wall MR imaging was rated on a 5-point scale. Twenty-seven patients with 29 aneurysms were included. The sensitivity, specificity, positive predictive value, and negative predictive value of TOF-MRA, high-resolution vessel wall MR imaging, and high-resolution vessel wall MR imaging combined with TOF-MRA for diagnosing aneurysm remnants were 80.0%, 100.0%, 100.0%, and 82.4%; 53.3%, 100.0%, 100.0%, and 66.7%; and 93.3%, 100.0%, 100.0%, and 93.3%, respectively. For the visualization of the stented artery, the mean score of high-resolution vessel wall MR imaging was significantly higher than that of TOF-MRA (4.88 [SD, 0.32] versus 2.53 [SD, 1.25], P < .001). In the evaluation of parent artery patency (normal or pathologic), whereas TOF-MRA had a sensitivity, specificity, positive predictive value, and negative predictive value of 100.0%, 8.0%, 14.8%, and 100.0%, respectively, high-resolution vessel wall MR imaging was completely consistent with the DSA. High-resolution vessel wall MR imaging combined with TOF-MRA at 3T showed good diagnostic performance in the follow-up of intracranial vertebrobasilar dissecting aneurysms after reconstructive endovascular treatment.

Endovascular treatment of intracranial vertebral artery unruptured dissecting aneurysms: Comparison of flow diversion and stent-assisted coiling or stenting alone.

PurposeTo investigate the effect and safety of flow diverters in the treatment of unruptured dissecting intracranial aneurysms of the vertebral artery in comparison with stent-assisted coiling or stenting alone.Materials and methodsPatients with unruptured dissecting intracranial aneurysms of the vertebral artery treated with the flow diverter, stent-assisted coiling, or stenting alone were retrospectively enrolled. The clinical data were analyzed and compared.ResultsTwenty-five patients were enrolled in the flow diversion group and 42 patients in the stenting group. Twenty-six flow diverters were deployed in the flow diversion group. Immediate angiography revealed contrast agent retention within the aneurysm cavity in all patients. In the stenting group, 48 stents were deployed, and immediate angiographic outcome showed O'Kelly-Marotta (OKM) grade D in 18 (42.9%) aneurysms, grade C in 16 (38.1%), and grade B in 8 (19.0%). Periprocedural ischemic complications of thrombosis occurred in two (4.8%) patients and were treated with thrombolysis. In the flow diversion group, 19 (76%) patients underwent angiographic follow-up 3–46 (median 24) months after the procedure, with the OKM grade D in 11 (57.9%) patients, C in two (10.5%), and B in six (31.6%). The aneurysm recurrence rate was zero, and all diverters remained patent. Asymptomatic instent stenosis occurred in two (10.5%) patients. In seven of the ten patients with mild or moderate parent artery stenosis before the procedure who experienced angiographic follow-up, the stenosis was improved in five (71.4%) patients. In the stenting group, angiographic follow-up was carried out in 33 (78.6%) patients 6–58 months (median 34) after the procedure, with OKM grade D in 22 (66.7%) patients, grade C in five (15.2%), grade B in three (9.1%), and aneurysm recurrence (grade B, with increased contrast agent into the aneurysm cavity) in three (9.1%). Five (16.7%) patients experienced asymptomatic instent stenosis, and six of the 12 patients (50%) with parent artery stenosis were improved.ConclusionFlow diverters with or without selective adjunctive coiling for the treatment of unruptured dissecting intracranial aneurysms of the vertebral artery may be safe and effective with good occlusion effects not inferior to those of stent-assisted coiling and stenting alone even though the long-term effect still warrants confirmation.

Challenging the diagnosis of a posterior circulation dissecting aneurysm

I ntracranial vertebral dissections have polymorphs clinical presentations and can lead to haemorrhagic complications if they are intracranial. We here describe a case of a thrombosed dissecting aneurysm of postero-inferior cerebellar artery (PICA) revealed by a Wallenberg syndrome preceded by headaches. A 23-year-old patient, without neurological or vascular past medical history, was admitted for dizziness preceded by headache. The clinical examination on admission revealed an incomplete Wallenberg syndrome, associating hemiface sensitive deficit, Horner's syndrome, dysmetria and nystagmus. The brain MRI showed a latero-medullary infarct with a homolateral PICA thrombosed dissecting aneurysm. The diagnosis of intracranial dissecting aneurysms needs particular caution because aneurysm sac thrombosis can give false reassurance on angiographic MR sequences. Moreover, the anatomic features of intracranial artery walls make them prone to sub-adventitial dissection and subsequent subarachnoid haemorrhages. Therefore, antithrombotic therapy should be used with caution, due to the risk of bleeding in these intracranial dissections.

Flow Diverter Device for Treatment of Cerebral Aneurysm with Short-Term Follow Up: Two Case Reports

&lt;p&gt;The flow diverter device (FDD) is an important treatment method for cerebral aneurysms, especially for intracranial dissecting aneurysms. This paper is the result of FDD treatment for two cases of vertebral dissecting aneurysm (VADA) patients and short-term follow-up at 3 months. All two cases were targeted for unruptured cerebral aneurysm, and 4-vessel angiography was performed as a follow-up examination for 3 months after receiving the procedure. As result, it was possible to shorten the period of use of antiplatelet drugs.&lt;/p&gt;&lt;p&gt;In the case of VADA, there are limitations in general coiling procedures or conventional surgical treatment methods. In that sense, the FDD treatment method can be a very effective alternative treatment of VADA&lt;/p&gt;

Pipeline Embolization Device for the Treatment of Unruptured Intracranial Dissecting Aneurysms.

Background: Intracranial dissecting aneurysms (IDAs) are rare but pose significant challenges to treatment. The pipeline embolization device (PED) has been demonstrated to be an effective treatment option with excellent outcomes. Herein, we report our experience with patients treated with the PED for unruptured IDAs.Methods: We retrospectively reviewed our hospital database and identified patients who were treated with PEDs for unruptured IDAs between March 2016 and September 2020. Data including demographics, clinical presentation, aneurysm characteristics, procedural details, intra- or peri-procedural complications, and follow-up details were collected.Results: Eighty patients (61 men, 76.25%) were treated with PED for unruptured IDAs. The most common symptoms were headache (34, 42.5%), dizziness (29, 36.25%), and nausea or vomiting (15, 18.75%). Of these patients, 73 had one aneurysm, and seven harbored two aneurysms. All of them achieved successful PED deployment. Six patients experienced intra- or peri-procedural complications including perforator artery occlusion, thromboembolic, hemorrhagic events, and falling of the stent into the aneurysm sac. Follow-up with digital subtractive angiography was available for 29 patients with a median of 6 months, and 28 (96.56%) patients had aneurysm occlusion. Late thrombosis occurred in four patients, and two of them had unfavorable outcomes. Clinical follow-up showed that a favorable clinical outcome was achieved in 76 (95%) patients, and the mortality rate was 3.75%.Conclusion: Treating unruptured IDAs is safe and effective with long-term favorable clinical and angiographic outcomes. However, the complications of this treatment should be noted. Careful selection of appropriate patients and individualized antiplatelet therapy might be needed.

Deconstructive versus reconstructive endovascular approaches for intracranial dissecting aneurysms

BackgroundThe annual incidence of the intracranial dissecting aneurysms is about 1 to 1.5 per 100,000. This is a well-known cause of stroke and subarachnoid hemorrhage in young and middle-aged patients (Santos-Franco et al. in Neurosurg Rev, 2008. https://doi.org/10.1007/s10143-008-0124-x). Various surgical and endovascular treatment methods have been proposed for intracranial dissecting aneurysms. All treatment methods aim to reduce the blood flow in the dissected region. Deconstructive techniques sacrifice the parent artery, whereas reconstructive techniques aim to maintain a parent artery (Stéphanie et al. in Lancet Neurol 14(6):640–654, 2015. https://doi.org/10.1016/S1474-4422(15)00009-5). Due to its dissecting nature, wall friability can make surgical clipping difficult and even risky. On the other hand, recanalization after coiling alone is almost certain. Therefore, deconstructive modalities of treatment like trapping or parent vessel occlusion, performed either surgically or endovascularly, have predominated for managing those lesions, usually with good results. Nevertheless, in absence of efficient collateral pathways, the deconstructive technique carries an ischemic risk. In situations in which parent artery preservation is mandatory, the use of stent-assisted techniques may be the most appropriate choice (de Barros Faria et al. in Am J Neuroradiol 32(11):2192–2195, 2011. https://doi.org/10.3174/ajnr.A2671). However, the usage of stent with recently ruptured aneurysms is always perplexing due to the necessity of dual antiplatelet administration. Hence the management of dissecting aneurysms remain challenging.ResultsBetween January 2017 and July 2019, 19 patients presenting with intracranial dissecting aneurysms were referred to our department for endovascular treatment. Among the nineteen patients, 11 cases were treated by parent artery occlusion representing 57.9% of the cases, and 7 cases (36.8%) were treated by artery preserving technique, and only one case (5.3%) was treated by combination of parent artery occlusion and artery preserving technique. One week after the intervention 26.3% of patients had no disability (mRS = 0), 47.4% had no significant disability (mRS = 1), 15.8% had slight disability (mRS = 2) and 10.5% had moderate to severe disability (mRS = 3–4). After three months we found an overall improvement of the clinical outcome, as 57.9% of patients had no disability (mRS = 0), 26.3% had no significant disability (mRS = 1) and 15.8% had mild disability (mRS = 2). Finally, after six months reassessment with angiography showed that 89.5% of patients had stable aneurysmal occlusion, and 10.5% had recurrence of aneurysm.ConclusionsBoth endovascular approaches, whether parent artery occlusion or artery preserving technique showed favorable outcome which indicates the safety and efficacy of both approaches if selected properly according to the morphology of the aneurysm.

ESO guideline for the management of extracranial and intracranial artery dissection.

The aim of the present European Stroke Organisation guideline is to provide clinically useful evidence-based recommendations on the management of extracranial artery dissection (EAD) and intracranial artery dissection (IAD). EAD and IAD represent leading causes of stroke in the young, but are uncommon in the general population, thus making it challenging to conduct clinical trials and large observational studies. The guidelines were prepared following the Standard Operational Procedure for European Stroke Organisation guidelines and according to GRADE methodology. Our four recommendations result from a thorough analysis of the literature comprising two randomized controlled trials (RCTs) comparing anticoagulants to antiplatelets in the acute phase of ischemic stroke and twenty-six comparative observational studies. In EAD patients with acute ischemic stroke, we recommend using intravenous thrombolysis (IVT) with alteplase within 4.5 hours of onset if standard inclusion/exclusion criteria are met, and mechanical thrombectomy in patients with large vessel occlusion of the anterior circulation. We further recommend early endovascular or surgical intervention for IAD patients with subarachnoid hemorrhage (SAH). Based on evidence from two phase 2 RCTs that have shown no difference between the benefits and risks of anticoagulants versus antiplatelets in the acute phase of symptomatic EAD, we strongly recommend that clinicians can prescribe either option. In post-acute EAD patients with residual stenosis or dissecting aneurysms and in symptomatic IAD patients with an intracranial dissecting aneurysm and isolated headache, there is insufficient data to provide a recommendation on the benefits and risks of endovascular/surgical treatment. Finally, nine expert consensus statements, adopted by 8 to 11 of the 11 experts involved, propose guidance for clinicians when the quality of evidence was too low to provide recommendations. Some of these pertain to the management of IAD (use of IVT, endovascular treatment, and antiplatelets versus anticoagulation in IAD with ischemic stroke and use of endovascular or surgical interventions for IAD with headache only). Other expert consensus statements address the use of direct anticoagulants and dual antiplatelet therapy in EAD-related cerebral ischemia, endovascular treatment of the EAD/IAD lesion, and multidisciplinary assessment of the best therapeutic approaches in specific situations.

High-resolution vessel wall magnetic resonance imaging for depicting imaging features of unruptured intracranial vertebrobasilar dissecting aneurysms.

ObjectiveTo demonstrate the application value of high-resolution vessel wall magnetic resonance imaging (HR-VW-MRI) for depicting the imaging features of unruptured intracranial vertebrobasilar dissecting aneurysms (VBDAs).MethodsHR-VW-MRI data of 49 patients with suspected unruptured VBDAs were retrospectively analyzed. The presence of intramural hematomas (IMH), double lumens, intimal flaps, and outer diameter enlargements were recorded. Specificity and sensitivity were calculated for both two-dimensional (2D) and three-dimensional (3D) sequences. Additionally, IMH volumes were measured and posterior inferior cerebellar artery (PICA) involvement was analyzed.ResultsThirty-five VBDAs were confirmed in 34 patients. The overall sensitivity and specificity were 0.889 (95% confidence interval [CI]: 0.730–0.964) and 0.769 (95% CI: 0.460–0.938) for 2D sequences, and 0.917 (95% CI: 0.764–0.978) and 0.846 (95% CI: 0.537–0.973) for 3D sequences, respectively. Intimal flaps were detected in 57.1%, 87.5%, and 71.4% of all cases on 2D pre-contrast T1-weighted, contrast-enhanced T1-weighted, and 3D T1-weighted black-blood (BB) images, respectively. There was no significant difference in IMH volume between 3D T1-weighted BB and magnetization-prepared rapid gradient-echo sequences. PICA involvement was best visualized using 3D T1 sequences.Conclusion3D T1-weighted BB MRI provided good visualization of VBDA features, with large coverage, and was useful for detecting dissection flaps.

Real-time change of optic nerve sheath diameter after rebleeding of ruptured intracranial dissecting aneurysm

Ultrasonographic measurement of optic nerve sheath diameter (ONSD) has been validated to detect and monitor the increased intracranial pressure (IICP) in neurosurgical field. Especially, the ONSD has been known to reflect well the ICP in case of intracranial hemorrhage (ICH) occurring in the anterior circulation of intracranial vascular system, however it has not been well elucidated the role of ONSD in the posterior circulating vascular problems. A 43-year-old man presented with a subarachnoid hemorrhage with intraventricular hemorrhage due to rupture of dissecting aneurysm at right vertebral artery, and immediately performed the stent-assisted coil embolization. Two day after coil embolization, he became nearly alert without definite neurologic deficits. The ONSD was reduced from 5.8 mm to 5.5 mm. The 10th postoperative days, the patient suddenly changed into stuporous mentality due to rebleeding of aneurysm. The ONSD was enlarged to 6.7 mm. We report a case of intimate relationship between ONSD and IICP after rupture of dissecting aneurysm located in posterior circulation.

Low-profile visible intraluminal support stent-assisted embolization therapy for intracranial dissecting aneurysms: A retrospective analysis of six cases.

Endovascular Embolization (EVE) of aneurysms is a very effective and efficient treatment modality. Nevertheless, a few complications have been reported after EVE of aneurysms. Our study therefore evaluated the safety and efficacy of Low-profile Visible Intraluminal Support (LVIS) stentassisted EVE for intracranial Dissecting Aneurysms (DAs). We conducted a retrospective study to identify patients with DAs who were treated with LVIS stent from July 2015 to September 2018. The DAs were categoried into ruptured and unruptured. The arteries harbouring the aneurysm were identified in all cases. LVIS device stent assisted coil EVE treatment modality was utilized to treat all the patients. Surgical safety, immediate surgery outcome, recurrence rate and imaging follow-up results of all patients were analysed. The Glasgow Outcome Scale (GOS) score of all patients where assessed during discharge. Cerebral angiography of all patients were reevaluated on scheduled visits from three months up to one year after their operations. A total of Six DA patients were identified during our analysis. Four of the cases were ruptured DAs while two cases were unruptured. The DAs originated from the Internal Carotid Artery (ICA) in two cases, while in the remaining four cases, the DAs originated from vertebral artery (VA). Stents and coils were successfully implanted in all six patients. The DAs were embolized satisfactorily and the parent arteries were patent immediately after the operations. We obsereved 5 points GOS score in four cases and 4 points in two cases. No aneurysmal recurrece, no stent collapse or displacement was obsereved in all cases during follow-ups. Our study suggests that, LVIS stent-assisted EVE is simple, safe and effective in the treatment of DAs.

Pediatric Patient With a Giant Vertebrobasilar Dissecting Aneurysm Successfully Treated With Three Pipeline Embolization Devices.

Pediatric intracranial dissecting aneurysms are rare (1), and treating this type of aneurysm in the vertebrobasilar circulation is more difficult. As an off-label application, pipeline embolization devices (PEDs) for posterior circulation dissecting aneurysms are reported to have good therapeutic effect (2). However, studies have found that PEDs for large or giant vertebrobasilar dissecting aneurysms have a poor effect and are associated with disastrous consequences for patients (3). PEDs are feasible for vertebrobasilar dissecting aneurysms (4); however, few reports discuss using PEDs to span the entire segment of the basilar artery. Because there are more perforating arteries in the basilar artery, it is more prudent to use PEDs in this artery. We report a case of a pediatric patient with a giant vertebrobasilar dissecting aneurysm successfully treated with three PEDs combined with right vertebral artery occlusion, without complications. The patient's headache symptoms resolved fully 3 months after the procedure, and the aneurysm was completely healed and excellent reconstruction of the left vertebral artery was seen 4 months post-procedure, using digital subtraction angiography.

Dynamic contrast-enhanced MRI analysis for prognosis of intracranial dissecting aneurysm with intramural haematoma after endovascular treatment: an observational registry study

Background and purposeIntracranial dissecting aneurysm (IDA) with intramural haematoma (IMH) is an intractable cerebrovascular disease. The outcome of IDA with IMH after endovascular treatment varies across different individuals: some IMHs...

Practical value of three-dimensional high resolution magnetic resonance Vessel Wall imaging in identifying suspicious intracranial vertebrobasilar dissecting aneurysms

BackgroundDirect evidence of intimal flaps, double lumen and intramural haematomas (IMH) is difficult to detect on conventional angiography in most intracranial vertebrobasilar dissecting aneurysms (VBDAs). Our purpose was to assess the value of three-dimensional high-resolution magnetic resonance vessel wall imaging (3D HRMR VWI) for identifying VBDAs.MethodsBetween August 2013 and January 2016, consecutive patients with suspicious VBDAs were prospectively enrolled to undergo catheter angiography and VWI (pre- and post-contrast). The lesion was diagnosed as definite VBDA when presenting direct signs of dissection; as possible when only presenting indirect signs; and as segmental ectasia when there was local dilation and wall thickness similar to adjacent normal artery’s without mural thrombosis.ResultsTwenty-one patients with 27 lesions suspicious for VBDAs were finally included. Based on findings of VWI and catheter angiography, definite VBDA was diagnosed in 25 and 7 lesions (92.6%, vs 25.9%, p < 0.001), respectively; possible VBDA in 0 and 20 (0 vs 74.1%), respectively; and segmental ectasia in 2 and 0 (7.4% vs 0%), respectively. On VWI and catheter angiography, intimal flap was detected in 21 and 7 lesions (77.8% vs 25.9%, p = 0.001), respectively; double lumen sign in 18 and 7 (66.7% vs 25.9%, p = 0.003), respectively; and IMH sign in 14 and 0 (51.9% vs 0), respectively.Conclusions3D HRMR VWI could detect direct dissection signs more frequently than catheter angiography. This may help obtain definite diagnosis of intracranial VBDAs, and allow accurate differentiation between dissecting aneurysm and segmental ectasia as well. Further prospective study with larger sample was required to investigate the superiority of HRMR VWI for definite diagnosis of intracranial VBDAs than catheter angiography.

The Fate of Unruptured Intracranial Vertebrobasilar Dissecting Aneurysm with Brain Stem Compression According to Different Treatment Modalities.

Unruptured intracranial vertebrobasilar dissecting aneurysms with brain stem compression are difficult to treat. In the present study, the clinical and radiologic outcomes of unruptured intracranial vertebrobasilar dissecting aneurysms with brain stem compression based on different treatment modalities were evaluated. This study included 28 patients with unruptured intracranial vertebrobasilar dissecting aneurysms with brain stem compression treated from January 2009 to December 2017. Treatment methods were observation (n = 6), stent-assisted coil embolization (n = 9), parent artery occlusion (n = 6), and flow diversion (n = 7). The data of baseline characteristics, change of aneurysm size, retreatment rate, stroke occurrence, and alteration of the mRS score were obtained from retrospective chart review. The initial size of dissecting aneurysms was largest in the flow diversion group (22.5 ± 7.7 mm), followed by parent artery occlusion (20.3 ± 8.4 mm), stent-assisted coil embolization (11.7 ± 2.2 mm), and observation (17.8 ± 5.5 mm; P = .01) groups. The reduction rate of aneurysm size was highest in the parent artery occlusion group (26.7 ± 32.1%), followed by flow diversion (14.1% ± 28.7%), stent-assisted coil embolization (-17.9 ± 30.3%), and observation (-31.5 ± 30.8%; P = .007) groups. Additional treatment was needed in the observation (4/6, 66.7%) and stent-assisted coil embolization (3/9, 33.3%; P = .017) groups. Improvement of the mRS score on follow-up was observed in the flow diversion (6/7, 85.7%) and parent artery occlusion (4/6, 66.7%) groups but not in the stent-assisted coil embolization and observation groups. A worsened mRS score was most common in the observation group (4/6, 66.7%), followed by stent-assisted coil embolization (3/9, 33.3%), parent artery occlusion (2/6, 33.3%), and flow diversion (0/7, 0%) groups. When treating intracranial vertebrobasilar dissecting aneurysms with brain stem compression, parent artery occlusion and flow diversion should be considered to reduce aneurysm size and improve the mRS score.

Endovascular treatment of ruptured and unruptured intracranial dissecting aneurysms

ObjectivesDissecting aneurysms are rare as contrasted with their saccular counterparts, yet they stay hard to treat and are related with high rates of rebleeding and morbidity. Material & methodsIn this study, we have reviewed dissecting aneurysms of both anterior and posterior circulation, both ruptured and unruptured, including natural history, endovascular treatment and clinical outcome. They account for 3–7% of cases of nontraumatic subarachnoid hemorrhage. Surgical treatment carries a significant risk of neurological complications predominantly lower cranial nerve deficits because of the close relationship of the posterior circulation aneurysm with the brain stem and cranial nerves. ResultsA total of 28 ruptured and unruptured dissecting aneurysms in both anterior and posterior circulation were treated endovascularly from January 2015 till October 2018. Out of 28, 23 of the aneurysms were in posterior circulation and 5 were in anterior circulation. All the cases were technically successful except in 1 case. Procedure related complications were seen in 9 patients which were transient except in one patient who died. Follow up studies showed stable and complete occlusion of aneurysms in all patients except in 1 case in which recanalization was seen. ConclusionDissecting aneurysms are dynamic lesions with variable and unpredictable evolution and a through treatment is warranted. Endovascular treatment by coiling and parent artery occlusion is relatively safe and effective treatment of dissecting intracranial aneurysms.

A Case of Segmental Arterial Mediolysis:Subarachnoid Hemorrhage Followed by Abdominal Bleeding

We describe a case involving subarachnoid and intraperitoneal hemorrhage due to segmental arterial mediolysis(SAM). A 77-year-old female patient with sudden subarachnoid hemorrhage was immediately transferred to our institution. The hemorrhage was classified as grade 2 according to the World Federation of Neurosurgical Societies system. The patient was a non-smoker and did not drink alcohol regularly. A right internal carotid aneurysm was detected using CT angiography and was clipped during frontotemporal craniotomy. Bleeding was observed from the anterior wall of the internal carotid artery, and the tear was clipped. The patient had an uneventful postoperative course until sudden cardiopulmonary arrest eight days after craniotomy. She died of massive intraperitoneal hemorrhage. Autopsy revealed that the hemorrhage was due to dissection of the celiac artery. Tunica media denaturation was observed not only in the celiac artery, but also in the splenic and internal carotid arteries, which exhibited ruptured aneurysms, and the patient was diagnosed with segmental arterial mediolysis(SAM). SAM is an arterial degenerative disease affecting the medial layer of the arterial and dissecting walls. Multiple lesions are sometimes found. Radiographic imaging findings of SAM are similar to those of dissecting aneurysms, which are characterized by a single continuous dissection of the medial layer. As observed in this case, abdominal bleeding caused by SAM can occur after intracranial bleeding. When surgeons encounter unusual intracranial dissecting aneurysms, SAM should be considered as a differential diagnosis.

The diagnosis and treatment of intracranial arterial dissection and dissecting aneurysms

Objective To investigate the clinical characteristics of intracranial arterial dissection (IAD) and intracranial dissecting aneurysms (IDA) and to evaluate the advantages and disadvantages of various diagnostic and therapeutic methods. Methods From December 2003 to December 2016, a total of 86 cases of intracranial artery dissection and dissecting aneurysms were treated at Neurosurgery Department, Wuhan General Hospital of PLA. Sixty-five patients were treated with endovascular therapy. Among them, 7 patients were treated with coil embolization, 38 with stent overlapping technique, 18 with stent-assisted coiling and 2 with coil-assisted silk embolization. Twenty-one patients did not undergo surgical treatment. The degree of embolization of each patient was inspected immediately after the endovascular therapy. The patients were followed up to assess mRS (modified Rankin scale) and recurrence through CTA or DSA. Results Sixty-five cases were treated successfully with endovascular treatment. The post-procedure DSA demonstrated that 53 cases were totally embolized and the other 12 cases were partially embolized. There were 3 patients developing neurologic deficit and 1 death due to re-bleeding. Among 21 cases undergoing conservative treatment, 5 cases died due to re-bleeding. Sixty-four cases were followed up for 6-12 months with an average of 8.7 months. There were 59 patients with favorable outcome (mRS: 0-1) and 5 patients with unfavorable outcome (mRS: > 2). The follow-up CTA or DSA suggested that 3 cases that were embolized partially with stent-assisted had recurrence with aneurysm enlargement. Reoperations were implemented in those 3 cases with parent artery occlusion in 2 cases and supplementary coiling in the other one. Conclusions The IAD and IDA are relatively rare kinds of cerebrovascular diseases with main manifestation of subarachnoid hemorrhage. The occurrence and progression of IAD and IDA are related to multiple factors and endovascular treatment usually leads to favorable outcome. Stent overlapping technique and stent-assisted coiling seem to be the primary endovascular therapies. Occlusion of lesioned vessel or parent artery could be considered as complementary method. Key words: Aneurysm, dissecting; Intracranial artery dissection; Diagnosis, differential; Endovascular treatment; Treatment outcome