Magnetic Resonance Imaging Follow-Up of Large or Giant Vertebrobasilar Dissecting Aneurysms After Total Embolization on Angiography

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

BACKGROUND AND PURPOSE

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.

MATERIALS AND METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Therapeutic dilemmas regarding giant aneurysms of the intracranial vertebral artery causing medulla oblongata compression

BACKGROUND

Giant aneurysms of the intracranial vertebral artery are very rare cerebrovascular lesions. Due to the rarity of these aneurysms, we know little about them.

METHODS

We performed a systematic review of the English literature by searching the PubMed database. The inclusion criteria were as follows: (a) the full text was available and (b) complete clinical data were available.

RESULTS

A total of 45 articles were identified, containing 53 patients (53 aneurysms). The patients were aged from 5 to 77 years (48.8 ± 20.8 years). Four patients receiving conservative treatment died. The remaining 49 patients were divided into the aneurysm removal group (n = 17) and the aneurysm reserve group (n = 32). The outcomes of the 49 treated cases could be obtained in 45 cases, 31 of which (68.9%, 31/45) had a Glasgow outcome scale score of 4-5.

CONCLUSIONS

It is still difficult to treat intracranial giant vertebral artery aneurysms, regardless of the treatment selected. Because of the malignant natural history, aggressive treatment is still advocated.

Unfavorable Outcomes Related to Endovascular Treatment of Giant Vertebrobasilar Aneurysms

Background: Giant vertebrobasilar aneurysms (GVBAs) have an unfavorable natural history if left untreated and often pose a sizeable challenge to endovascular treatment. The aim of this study was to analyze the angiographic and clinical outcomes of GVBAs treated by various endovascular procedures. Methods: Between January 2010 and September 2018, 27 patients with 27 GVBAs treated endovascularly were enrolled in this consecutive study. The clinical and angiographic features, treatment modalities, and outcomes were analyzed. Results: The patient cohort comprised 21 men (77.8%) and 6 women (22.2%) of mean age 42.7 ± 18.9 years (range, 6-65 years). The most common presenting symptom was compressive symptoms, present in 15 patients (55.6%). None of the GVBAs was ruptured. Of the 27 GVBAs, 23 aneurysms were dissecting aneurysm with intramural hematoma and 4 aneurysms were saccular. Regarding treatment approach, internal trapping was used in 5 aneurysms, stent-assisted coil embolization in 10, sole stenting in 4, and flow diverters in 8. Overall, 12 patients (44.4%) had an unfavorable angiographic or clinical outcome: 3 patients presented with post-operative complications and subsequent death, and 9 with poor prognosis during follow-up. Conclusions: Patients with GVBAs may not benefit from endovascular treatment. Newer-generation devices are necessary to provide more optimal therapy for the management of these complex lesions.

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

BACKGROUND AND PURPOSE

Intracranial 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 stop growing after endovascular treatment, while others continue to grow, even after embolisation of the parent artery. Currently, the mechanism for the continuous growth of IMH after endovascular treatment is still unclear. Continuous haemorrhage of the vasa vasorum in the IMH is considered to be associated with continuous enlargement of the IMH; however, this theory has not been proved by in vivo imaging.

METHODS AND ANALYSIS

This study will establish a prospective cohort of 80 patients who had an IDA with IMH and received endovascular treatment. Demographic characteristics, IDA morphological characteristics and treatment characteristics will be collected prospectively. All patients will undergo dynamic contrast-enhanced MRI (DCE-MRI) before and 6 months after the endovascular treatment. According to the follow-up results of the MRI, the IDAs will be divided into two groups: a haematoma stabilisation group and a haematoma enlargement group. Then, quantitative analysis of the vasa vasorum in the IMH will be performed, and differences between the two groups will be compared with determine the association between DCE-MRI related parameters and the outcomes of IMH changes.

ETHICS AND DISSEMINATION

The research was approved by the ethics committee of Beijing Tian Tan Hospital (KY 2019-024-03) and written informed consents would be obtained from all patients included in this study. The results of this study will be disseminated in professional printed media.

TRIAL REGISTRATION NUMBER

NCT03940859. Registered: 7 May, 2019. https://clinicaltrials.gov/ct2/show/NCT03940859.

Delayed extensive brain edema caused by the growth of a giant basilar apex aneurysm treated with basilar artery obliteration: a case report

Background

Partially thrombosed giant aneurysms at the basilar apex (BA) artery are challenging lesions with a poor prognosis if left untreated. Here we describe a rare case of extensive brain edema after growth of a surgically treated and thrombosed giant basilar apex aneurysm.

Case presentation

We performed a proximal surgical basilar artery occlusion on a 64-year-old female with a partially thrombosed giant BA aneurysm. MRI showed no ischemic lesions but showed marked edema adjacent to the aneurysm. She had a good recovery, but 3 months after surgical occlusion, her gait deteriorated together with urinary incontinence and worsening right hemiparesis. MRI showed that the aneurysm had grown and developed intramural hemorrhage, which caused extensive brain edema and obstructive hydrocephalus. She was treated by a ventriculoperitoneal shunt placement. Follow-up MRI showed progressive brain edema resolution, complete thrombosis of the lumen and shrinkage of the aneurysm. At 5 years follow-up the patient had an excellent functional outcome.

Conclusions

Delayed growth of a surgically treated and thrombosed giant aneurysm from wall dissection demonstrates that discontinuity with the initial parent artery does not always prevent progressive enlargement. The development of transmural vascular connections between the intraluminal thrombus and adventitial neovascularization by the vasa vasorum on the apex of the BA seems to be a key event in delayed aneurysm growth. Extensive brain edema might translate an inflammatory edematous reaction to an abrupt enlargement of the aneurysm.

China Intracranial Aneurysm Project (CIAP): protocol for a registry study on a multidimensional prediction model for rupture risk of unruptured intracranial aneurysms

BACKGROUND

Ruptured aneurysms, the commonest cause of nontraumatic subarachnoid hemorrhage, can be catastrophic; the mortality and morbidity of affected patients being very high. Some risk factors, such as smoking, hypertension and female sex have been identified, whereas others, such as hemodynamics, imaging, and genomics, remain unclear. Currently, no accurate model that includes all factors for predicting such rupture is available. We plan to use data from a large cohort of Chinese individuals to set up a multidimensional model for predicting risk of rupture of unruptured intracranial aneurysms (UIAs).

METHODS

The China Intracranial Aneurysm Project-2 (CIAP-2) will comprise screening of a cohort of 500 patients with UIA (From CIAP-1) and focus on hemodynamic factors, high resolution magnetic resonance imaging (HRMRI) findings, genetic factors, and biomarkers. Possible risk factors for rupture of UIA, including genetic factors, biomarkers, HRMRI, and hemodynamic factors, will be analyzed. The first project of the China Intracranial Aneurysm Project (CIAP-1; chaired by the Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China) will prospectively collect a cohort of 5000 patients with UIA from 20 centers in China, and collect baseline information for each patient. Multidimensional data will be acquired in follow-up assessments. Statistically significant clinical features in the UIA cohort will also be analyzed and integrated into the model for predicting risk of UIA rupture. After the model has been set up, the resultant evidence-based prediction will provide a preliminary theoretical basis for treating aneurysms at high risk of rupture.

DISCUSSION

This study will explore the risk of rupture of aneurysms and develop a scientific multidimensional model for predicting rupture of unruptured intracranial aneurysms. Clinical Trials registration A Study on a Multidimensional Prediction Model for Rupture Risk of Unruptured Intracranial Aneurysms (CIAP-2), NCT03133624. Registered: 16 April 2017. https://clinicaltrials.gov/ct2/show/NCT03133624.

Quantitative Analysis of Intracranial Vertebrobasilar Dissecting Aneurysm with Intramural Hematoma After Endovascular Treatment Using 3-T High-Resolution Magnetic Resonance Imaging

OBJECTIVE

Quantitative measurements of intracranial vessel walls are reliable in 3-T high-resolution magnetic resonance imaging (HR-MRI). However, few reports have assessed the arterial wall after endovascular treatment (EVT) by 3-T HR-MRI. This study aimed to quantitatively analyze vessel walls in vertebrobasilar artery dissecting aneurysms after EVT.

METHODS

From May 2012 to December 2015, a total of 21 patients with 21 intracranial vertebrobasilar dissecting aneurysms (VBDAs) were enrolled in this consecutive study. All the VBDAs were characterized by intramural hematomas (IMHs ≥5 mm) and treated with reconstructive EVT. Images of preoperative and follow-up 3-T HR-MRI were used to evaluate the arterial wall. The relative signal intensity (RSI) of IMHs was quantified on T1-weighted imaging (T1WI) and magnetization-prepared rapid acquisition gradient-echo (MPRAGE).

RESULTS

Angiographic follow-up was performed for a mean of 9.19 ± 3.22 months. According to angiographic results at follow-up, 21 patients were divided into 2 groups (progressive group, n = 6; stable group, n = 15). In the progressive group, RSI of IMHs was significantly increased on MPRAGE of follow-up 3-T HR-MRI compared with that before treatment (P < 0.05), and the difference was not significant on T1WI. However, in the stable group, RSI of IMHs was significantly reduced after treatment (P < 0.05).

CONCLUSIONS

Persistent high signal intensity of IMHs in VBDAs after reconstructive EVT may be associated with the progression of VBDAs. It may also indicate an unsteady state of the aneurysm, which suggests that reconstruction of the parent artery is not satisfactory.

Endovascular Treatment of Spontaneous Intracranial Fusiform and Dissecting Aneurysms: Outcomes Related to Imaging Classification of 309 Cases

OBJECTIVE

To propose a modified classification system for spontaneous intracranial dissecting aneurysms (IDAs) that can guide treatment decisions.

METHODS

Between January 2010 and December 2015, 3183 consecutive patients were referred to our department for endovascular treatment of a cerebral aneurysm. Among this group, 309 patients harboring a total of 323 spontaneous IDAs were identified. Based on a modified imaging classification system, spontaneous IDAs were classified into 4 subtypes: classic dissecting aneurysm, segmental ectasia, dolichoectatic dissecting aneurysm, and large mural bleeding ectasia. A logistic regression analysis was conducted to identify predictors of clinical outcomes.

RESULTS

Of the 323 IDAs, 216 (66.87%) were treated with stent-assisted coiling, 47 (14.55%) with internal trapping, and 60 (18.58%) with sole stenting. Of the 309 patients, 8 (2.59%) suffered intraoperative complications, 40 (12.94%) experienced postoperative complications, 9 died (2.79%), and 1 (0.32%) had severe disability. The mean duration of clinical follow-up of the 309 patients was 10.40 months (range, 3-72 months). Imaging follow-up was available for 262 patients (274 IDAs), with a mean duration of 7.10 months (range, 3-60 months), and 24 aneurysm recurrences (9.16%) were noted. Aneurysm type was the sole independent predictor of different outcomes on logistic regression analysis (P = 0.004).

CONCLUSIONS

There was a strong relationship between the subtypes of spontaneous IDAs and clinical course. Our classification system is confirmed to be helpful in assessing patients' prognosis and guiding their treatment.