Preoperative evaluation of tumour consistency in pituitary macroadenomas: a machine learning-based histogram analysis on conventional T2-weighted MRI

PURPOSE

To evaluate the potential value of machine learning (ML)-based histogram analysis (or first-order texture analysis) on T2-weighted magnetic resonance imaging (MRI) for predicting consistency of pituitary macroadenomas (PMA) and to compare it with that of signal intensity ratio (SIR) evaluation.

METHODS

Fifty-five patients with 13 hard and 42 soft PMAs were included in this retrospective study. Histogram features were extracted from coronal T2-weighted original, filtered and transformed MRI images by manual segmentation. To achieve balanced classes (38 hard vs 42 soft), multiple samples were obtained from different slices of the PMAs with hard consistency. Dimension reduction was done with reproducibility analysis, collinearity analysis and feature selection. ML classifier was artificial neural network (ANN). Reference standard for the classifications was based on surgical and histopathological findings. Predictive performance of histogram analysis was compared with that of SIR evaluation. The main metric for comparisons was the area under the receiver operating characteristic curve (AUC).

RESULTS

Only 137 of 162 features had excellent reproducibility. Collinearity analysis yielded 20 features. Feature selection algorithm provided six texture features. For histogram analysis, the ANN correctly classified 72.5% of the PMAs regarding consistency with an AUC value of 0.710. For SIR evaluation, accuracy and AUC values were 74.5% and 0.551, respectively. Considering AUC values, ML-based histogram analysis performed better than SIR evaluation (z = 2.312, p = 0.021).

CONCLUSION

ML-based T2-weighted MRI histogram analysis might be a useful technique in predicting the consistency of PMAs, with a better predictive performance than that of SIR evaluation.

Added Value of Dynamic Contrast-Enhanced Magnetic Resonance Imaging in Predicting Response to Somatostatin Analogs in Acromegaly Patients

AIM

To investigate the added value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) sequences in predicting somatostatin analog (SSA) responses in patients with acromegaly.

MATERIAL AND METHODS

This study included 55 active acromegaly patients with macroadenoma. Mean and maximum signal intensities were measured using region of interests in T2-weighted (T2W) and DCE-MRI sequences. Semi-quantitative values indicating relative signal intensity ratios and contrast-enhanced kinetics were obtained. Bivariate and multivariate analyses were used to determine whether the pathological granulation pattern of adenomas (dense versus others) was associated with patients' demographic variables and semi-quantitative MRI parameters.

RESULTS

Three parameters formed the logistic model, x2(3)=23.278, p < 0.0001: age (odds ratio [OR]=1.08), hypointensity of adenomas in T2W images (OR=15.45), and high maximum enhancement ratio in the second interval (ER2max) values (OR=2195.74). The overall accuracy of this model was 85.45% with an area under the curve of 0.880. Sensitivity, specificity, positive predictive, and negative predictive values of the model were 68.75%, 92.31%, 78.58%, and 87.8%, respectively.

CONCLUSION

In patients with newly diagnosed acromegaly, the model created based on the relative T2W signal intensity, patient's age, and ER2 < submax parameter from DCE-MRI sequences might be used to more accurately predict SSA responses.

Apparent diffusion coefficient characteristics of parenchymal neuro-Behçet's disease

AIM

To evaluate apparent diffusion coefficient (ADC) characteristic of parenchymal neuro-Behçet's disease (NBD).

METHODS

We retrospectively reviewed cranial magnetic resonance imaging (MRI) examinations of NBD patients with acute or chronic parenchymal lesions. ADC measurements of the lesions and contralateral normal brain parenchyma were performed by a consensus of two radiologists. To compare the ADC value of the chronic and acute lesions, relative ADC values (rADC) were calculated. The ratio of the lesions' ADC to contralateral normal brain parenchyma ADC yielded a rADC value of the lesions. Contrast enhancement patterns and the locations of the lesions were also noted.

RESULTS

A total of 24 NBD patients with 45 parenchymal lesions, 25 acute, and 20 chronic, were enrolled in the study. A significant difference was observed between the mean ADC value of the acute lesions (1074.48 ± 138.31 m/s) and the mean ADC value of the contralateral normal brain parenchyma (841.20 ± 142.96 m/s; P < 0.0001). A significant difference was observed between the mean ADC value of the chronic lesions (1069.95 ± 143.95 m/s) and the mean ADC value of the contralateral normal brain parenchyma (793.90 ± 96.71 m/s; P < 0.0001). No significant difference was observed between the mean rADC (1.35 ± 0.20) and the mean rADC value of the chronic lesions (1.29 ± 0.15; P = 0.22).

CONCLUSIONS

ADC measurements might provide substantial information about the histopathological aspect of parenchymal NBD lesions.

Assessment of the common carotid artery wall stiffness by Shear Wave Elastography in Behcet's disease

AIM

To evaluate endothelial dysfunction and subclinical atherosclerosis in Behcet's disease (BD) by measuring the common carotid artery (CCA) wall stiffness and carotid intima-media thickness (CIMT).

MATERIALS AND METHODS

We prospectively evaluated CIMT and the CCA wall stiffness of 34 BD patients and 28 age/sex-matched controls. CIMT measurements were performed from the posterior wall of the carotid artery approximately 10 mm proximal to the initiation of the carotid bulb using B-mode ultrasound. The stiffness of the CCA was measured from the superficial wall of the CCA using shear wave elastography (SWE). SWE measurements were recorded as shear wave velocity (SWV) using m/s as a unit.

RESULTS

The mean right (0.5±0.11 mm) and left (0.5±0.14 mm) CIMT of the patients were significantly higher compared to the mean right (0.41±0.07 mm) and left (0.41±0.11 mm) CIMT of the healthy controls (p=0.001 and p= 0.003 respectively). The mean right (3.72±0.94 m/s) and left (3.57±0.72 m/s) CCA wall stiffness of the patients were significantly higher compared to the mean right (2.42±0.49 m/s) and left (2.56±0.49 m/s) CCA wall stiffness of the controls (p<0.001 for both).

CONCLUSIONS

SWE seems to be a promising modality to evaluate endothelial dysfunction in BD by interpreting the arterial stiffness, and SWE might be an important adjunct to clinical and laboratory findings, and imaging modalities to assess cardiovascular risk in BD. Moreover, SWE evaluation of the arterial stiffness might assist us to understand pathophysiological aspects of BD.

Predicting response to somatostatin analogues in acromegaly: machine learning-based high-dimensional quantitative texture analysis on T2-weighted MRI

OBJECTIVE

To investigate the value of machine learning (ML)-based high-dimensional quantitative texture analysis (qTA) on T2-weighted magnetic resonance imaging (MRI) in predicting response to somatostatin analogues (SA) in acromegaly patients with growth hormone (GH)-secreting pituitary macroadenoma, and to compare the qTA with quantitative and qualitative T2-weighted relative signal intensity (rSI) and immunohistochemical evaluation.

METHODS

Forty-seven patients (24 responsive; 23 resistant patients to SA) were eligible for this retrospective study. Coronal T2-weighted images were used for qTA and rSI evaluation. The immunohistochemical evaluation was based on the granulation pattern of the adenomas. Dimension reduction was carried out by reproducibility analysis and wrapper-based algorithm. ML classifiers were k-nearest neighbours (k-NN) and C4.5 algorithm. The reference standard was the biochemical response status. Predictive performance of qTA was compared with those of the quantitative and qualitative rSI and immunohistochemical evaluation.

RESULTS

Five hundred thirty-five out of 828 texture features had excellent reproducibility. For the qTA, k-NN correctly classified 85.1% of the macroadenomas regarding response to SAs with an area under the receiver operating characteristic curve (AUC-ROC) of 0.847. The accuracy and AUC-ROC ranges of the other methods were 57.4-70.2% and 0.575-0.704, respectively. Differences in predictive performance between qTA-based classification and the other methods were significant (p < 0.05).

CONCLUSIONS

The ML-based qTA of T2-weighted MRI is a potential non-invasive tool in predicting response to SAs in patients with acromegaly and GH-secreting pituitary macroadenoma. The method performed better than the qualitative and quantitative rSI and immunohistochemical evaluation.

KEY POINTS

• Machine learning-based texture analysis of T2-weighted MRI can correctly classify response to somatostatin analogues in more than four fifths of the patients. • Machine learning-based texture analysis performs better than qualitative and quantitative evaluation of relative T2 signal intensity and immunohistochemical evaluation. • About one third of the texture features may not be excellently reproducible, indicating that a reliability analysis is necessary before model development.

Single-stage planning for total cure of grade III-V brain arteriovenous malformations by embolization alone or in combination with microsurgical resection

PURPOSE

There are no established guidelines for treatment of Spetzler-Martin grade III-V brain arteriovenous malformations (bAVMs). The purpose of this study is to report our institutional experience in total obliteration/eradication of grade III-V bAVMs by single-stage planning of embolization combined with microsurgical resection when necessary.

METHODS

All patients harboring Spetzler-Martin (S-M) grade III-V bAVMs treated with single-stage planning between January 2006 and January 2018 were retrospectively reviewed. This treatment paradigm is applicable only to surgically accessible bAVMs and does not include deep-seated bAVMs. Indications for treatment, clinical presentation, imaging characteristics, and treatment outcomes were analyzed. Outcomes were assessed based on modified Rankin Scale.

RESULTS

A total of 31 patients were identified. Seventeen patients (54.8%) presented with hemorrhage, 10 (32.3%) with seizures, 3 (9.7%) with headaches, and 1 (3.2%) with progressive neurological deficit. Based on S-M grading system, 25 patients (80.6%) harbored grade III bAVM, 5 patients had grade IV bAVMs (16.1%), and 1 patient (3.2%) had a grade V bAVM. There were no treatment-related complications in 24/31 (77.4%) patients. Of the total of seven patients with complications, four patients had clinical deterioration. The long-term (> 6-month), non-disabling morbidity (mRS ≤ 2) rate was 6.5%. The long-term, disabling morbidity rate was 3.2% with a mortality of 3.2%. Complete angiographic obliteration was achieved in 30/31 (96.8%) patients.

CONCLUSION

Single-stage treatment strategy can be considered as an alternative to multistage embolization prior to surgery in grade III-V bAVMs. In this study, a high rate of total obliteration with relatively low rates of permanent morbidity and mortality was achieved.

Intracranial Serpentine Aneurysms: Spontaneous Changes of Angiographic Filling Pattern

BACKGROUND AND PURPOSE

Serpentine aneurysms are partially thrombosed aneurysms with an eccentrically located tortuous intra-aneurysmal vascular channel. The large size, distinctive neck anatomy, and supply of the brain parenchyma by the outflow tract pose technical challenges in treatment. The aim of this study was to discuss the endovascular treatment results and illustrate the dynamic nature of serpentine aneurysms. Spontaneous transformation of saccular and fusiform aneurysms into serpentine morphology, along with a case of serpentine-into-fusiform aneurysm transformation during follow-up, is presented.

MATERIALS AND METHODS

A retrospective analysis from 3 institutions revealed 15 patients with serpentine aneurysms who underwent diagnostic evaluation and endovascular treatment. Nine of the 15 patients underwent endovascular occlusion of the parent vessel with detachable balloon or coils. Six of the 15 patients underwent aneurysm and parent artery occlusion with coiling.

RESULTS

In 11 patients, improvement or resolution of symptoms was achieved by an endovascular approach without any treatment-related morbidity. Morbidity related to treatment in the immediate postoperative period was seen in 3 patients, with resolution of the deficits at long-term follow-up in 2 patients and persistence of a mild deficit in 1 patient. Endovascular treatment failed to achieve resolution of symptoms in a case with a basilar tip aneurysm treated by aneurysm coiling.

CONCLUSIONS

Serpentine aneurysms are dynamic structures with spontaneous transformation possible from a saccular or fusiform shape into a serpentine configuration. An endovascular approach by parent vessel occlusion or intra-aneurysmal occlusion is a successful treatment technique for serpentine aneurysms.

Intrathecal gadolinium-enhanced MR cisternography in patients with otorhinorrhea: 10-year experience of a tertiary referral center

PURPOSE

Despite a considerable amount of literature that has been published about the use of intrathecal gadolinium-enhanced MR cisternography (IGE-MRC), there is still relatively lack of evidence as to its long-term effects. Our purpose in this study was twofold: firstly, to assess the long-term safety of the IGE-MRC; secondly, to evaluate the diagnostic performance of IGE-MRC for detecting cerebrospinal fluid (CSF) leak in otorhinorrhea patients.

METHODS

We retrospectively reviewed our imaging and clinical database for the patients admitted to our department for the evaluation of their otorhinorrhea between 2008 and 2017. Two radiologists evaluated the imaging studies independently. Consensus data was used in the analysis. Medical record review and phone call were used for the long-term follow-up.

RESULTS

The retrospective review yielded 166 patients. Rhinorrhea was present in 150 (90.4%) patients and otorrhea in 16 (9.6%) patients. Overall, 67 patients (40.5% of all patients) underwent operation for repair of the CSF leak site. Beta-transferrin test was available and positive in 57 (34.3%) patients. Overall sensitivity of IGE-MRC and paranasal high-resolution CT (HRCT) was 89.3 and 72%, respectively. Within the first 24 h after the procedure, none of the patients experienced a significant complication or adverse reaction. Ninety-nine patients (59.6%) had medical record and telephone follow-up. The mean follow-up duration with call was 37.1 months. Three (3%) patients complained about severe headache 3-4 weeks after the procedure.

CONCLUSIONS

IGE-MRC is a minimally invasive and highly sensitive imaging technique. No adverse side effect during our long-term follow-up might strengthen and support the safety of IGE-MRC.

European Multicenter Study for the Evaluation of a Dual-Layer Flow-Diverting Stent for Treatment of Wide-Neck Intracranial Aneurysms: The European Flow-Redirection Intraluminal Device Study

BACKGROUND AND PURPOSE

Endoluminal reconstruction with flow-diverting stents represents a widely accepted technique for the treatment of complex intracranial aneurysms. This European registry study analyzed the initial experience of 15 neurovascular centers with the Flow-Redirection Intraluminal Device (FRED) system.

MATERIALS AND METHODS

Consecutive patients with intracranial aneurysms treated with the FRED between February 2012 and March 2015 were retrospectively reviewed. Complications and adverse events, transient and permanent morbidity, mortality, and occlusion rates were evaluated.

RESULTS

During the defined study period, 579 aneurysms in 531 patients (median age, 54 years; range, 13-86 years) were treated with the FRED. Seven percent of patients were treated in the acute phase (≤3 days) of aneurysm rupture. The median aneurysm size was 7.6 mm (range, 1-36.6 mm), and the median neck size 4.5 mm (range, 1-30 mm). Angiographic follow-up of >3 months was available for 516 (89.1%) aneurysms. There was progressive occlusion witnessed with time, with complete occlusion in 18 (20%) aneurysms followed for up to 90 ± 14 days, 141 (82.5%) for 180 ± 20 days, 116 (91.3%) for 1 year ± 24 days, and 122 (95.3%) aneurysms followed for >1 year. Transient and permanent morbidity occurred in 3.2% and 0.8% of procedures, respectively. The overall mortality rate was 1.5%.

CONCLUSIONS

This retrospective study in real-world patients demonstrated the safety and efficacy of the FRED for the treatment of intracranial aneurysms. In most cases, treatment with a single FRED resulted in complete angiographic occlusion at 1 year.

Is there an association between flow diverter fish mouthing and delayed-type hypersensitivity to metals?-a case-control study

PURPOSE

Flow diverters are increasingly used in the treatment of complex and giant intracranial aneurysms. However, they are associated with complications like late aneurysmal rupture. Additionally, flow diverters show focal structural decrease in luminal diameter without any intimal hyperplasia. This resembles a "fish mouth" when viewed en face. In this pilot study, we tested the hypothesis of a possible association between flow diverter fish-mouthing and delayed-type hypersensitivity to its metal constituents.

METHODS

We retrospectively reviewed patient records from our center between May 2010 and November 2015. A total of nine patients had flow diverter fish mouthing. A control group of 25 patients was selected. All study participants underwent prospective patch test to detect hypersensitivity to flow diverter metal constituents. Analysis was performed using logistic regression analysis and Wilcoxon sign rank sum test. Univariate and multivariate analyses were performed to test variables to predict flow diverter fish mouthing.

RESULTS

The association between flow diverter fish mouthing and positive patch test was not statistically significant. In multivariate analysis, history of allergy and maximum aneurysm size category was associated with flow diverter fish mouthing. This was further confirmed on Wilcoxon sign rank sum test.

CONCLUSION

The study showed statistically significant association between flow diverter fish mouthing and history of contact allergy and a small aneurysmal size. Further large-scale studies are needed to detect a statistically significant association between flow diverter fish mouthing and patch test. We recommend early and more frequent follow-up imaging in patients with contact allergy to detect flow diverter fish mouthing and its subsequent evolution.

Multicenter Experience with FRED Jr Flow Re-Direction Endoluminal Device for Intracranial Aneurysms in Small Arteries

BACKGROUND AND PURPOSE

Flow diverters are emerging as an endovascular treatment alternative for proximally located intracranial aneurysms. However, treatment of aneurysms at and beyond the circle of Willis is not well-established. We assessed the clinical safety and efficacy of the Flow Re-Direction Endoluminal Device Jr (FRED Jr) dedicated to small-vessel diameters between 2.0 and 3.0 mm.

MATERIALS AND METHODS

This was a multicenter observational clinical study of 42 patients with 47 aneurysms treated by a flow-direction technique with the FRED Jr. The primary end point for clinical safety was the absence of death, major or minor stroke, and TIA. The primary end point for treatment efficacy was complete and near-complete occlusion according to the O'Kelly-Marotta grading scale at follow-up after 1, 6, and 12 months.

RESULTS

The FRED Jr deployment was technically successful in all cases. In 39/42 (93%) patients, the primary safety end point was reached; in the 3 remaining patients, 1 disabling ischemic stroke, 1 minor stroke with complete recovery at discharge, and 1 TIA were observed. Two asymptomatic, completely reversible side-branch occlusions occurred. Angiographic (DSA or flat panel CT) and clinical follow-up were available after 1 month in 41/47 (87%), 6 months in 27/47 (57%), and 12 months in 11/47 (23%) aneurysms. The primary efficacy end point was reached at 1 month in 27/41 (66%), at 6 months in 21/27 (78%), and at 12 months in 11/11 (100%) aneurysms.

CONCLUSIONS

Deployment of the FRED Jr is safe and effective in the treatment of intracranial aneurysms located in small vessels.

European consensus conference on unruptured brain AVMs treatment (Supported by EANS, ESMINT, EGKS, and SINCH)

In December of 2016, a Consensus Conference on unruptured AVM treatment, involving 24 members of the three European societies dealing with the treatment of cerebral AVMs (EANS, ESMINT, and EGKS) was held in Milan, Italy. The panel made the following statements and general recommendations: (1) Brain arteriovenous malformation (AVM) is a complex disease associated with potentially severe natural history; (2) The results of a randomized trial (ARUBA) cannot be applied equally for all unruptured brain arteriovenous malformation (uBAVM) and for all treatment modalities; (3) Considering the multiple treatment modalities available, patients with uBAVMs should be evaluated by an interdisciplinary neurovascular team consisting of neurosurgeons, neurointerventionalists, radiosurgeons, and neurologists experienced in the diagnosis and treatment of brain AVM; (4) Balancing the risk of hemorrhage and the associated restrictions of everyday activities related to untreated unruptured AVMs against the risk of treatment, there are sufficient indications to treat unruptured AVMs grade 1 and 2 (Spetzler-Martin); (5) There may be indications for treating patients with higher grades, based on a case-to-case consensus decision of the experienced team; (6) If treatment is indicated, the primary strategy should be defined by the multidisciplinary team prior to the beginning of the treatment and should aim at complete eradication of the uBAVM; (7) After having considered the pros and cons of a randomized trial vs. a registry, the panel proposed a prospective European Multidisciplinary Registry.

Detection of wall and neck calcification of unruptured intracranial aneurysms with flat-detector computed tomography

OBJECT

Microsurgical clipping is a widely used surgical technique in intracranial aneurysm treatment. It can be difficult in large sized aneurysms, and those with wide necks, thick walls and calcification located in the vicinity of the neck. This study reviewed calcification of the intracranial aneurysm wall and its relation to patient age, gender, location and size of the aneurysm. A possible cut-off value after which the aneurysm calcification rate increases was also investigated to classify patients' risk factors for microclipping.

METHODS

A retrospective review of all unruptured intracranial aneurysms that underwent digital subtraction angiography at a single centre was performed. Flat-detector computed tomography images of the aneurysm were reviewed for aneurysm location, size and calcification. The independent samples t test and χ(2) test were used to show the relation between aneurysm wall calcification and patient age, gender, aneurysm localisation and size.

RESULTS

None of the reviewed factors were statistically significantly related to aneurysm calcification except aneurysm size (P < 0.01). Receiver operating characteristic curves showed aneurysms greater than 10.5 mm could be predicted to be calcified with a sensitivity of 80% and specificity of 63%.

CONCLUSION

In this study, the presence of calcification was related to aneurysm size. Larger aneurysms were more likely to be calcified. Aneurysms greater than 10.5 mm should be further investigated with a modality such as flat-detector computed tomography to show the calcification in detail, especially if microclipping is considered.

Endovascular Management of Superior Cerebellar Artery Aneurysms: Mid and Long-Term Results

AIM

Superior cerebellar artery (SCA) aneurysms are uncommon vascular lesions, thus data about their presentation and clinical management are limited. Our aim was to determine clinical presentation, angiographic findings and mid and long-term clinical and imaging results of endovascular treatment of 49 patients with SCA aneurysm.

MATERIAL AND METHODS

Forty-nine patients with SCA aneurysms underwent endovascular treatment (25 female, 24 male; mean age 46.7 years; range, 21-79 years) in our institution. Both aneurysms arising at the origin of SCA and peripheral SCA aneurysms were included to our retrospective study. 73.5% of the patients were presented with subarachnoid hemorrhage. Forty-two of 49 (85.7%) aneurysms were located in the origin of SCA. Mean aneurysm size was 6.5 mm (range 2-16 mm).

RESULTS

Forty-seven (95.9%) of the aneurysms were coiled with detachable coils. In two peripheral aneurysms, liquid embolic agent was used. Overall control angiographic occlusion rates were as follows: 87.5% (34/40) total occlusion and 12.5% (6/40) dog-ear remnant. All peripheral SCA aneurysms were occluded with the parent artery. Procedure related mortality was seen in one patient (2%) due to the rupture of another aneurysm. There was no procedure related permanent morbidity.

CONCLUSION

Endovascular treatment is an effective and safe option in both peripheral and proximal SCA aneurysms.

Primary diffuse leptomeningeal gliomatosis mimicking tuberculous meningitis

Primary diffuse leptomeningeal gliomatosis is a disease with an aggressive course that can result in death. To date, 82 cases have been reported. Here, the case of a 3-year-old male patient presenting with strabismus, headache, and restlessness is reported. Physical examination revealed paralysis of the left abducens nerve, neck stiffness, and bilateral papilledema. Tuberculous meningitis was tentatively diagnosed, and antituberculosis treatment was initiated when cranial imaging revealed contrast enhancement around the basal cistern. Craniocervical magnetic resonance imaging (MRI) was performed when there was no response to treatment, and it revealed diffuse leptomeningeal contrast enhancement around the basilar cistern, in the supratentorial and infratentorial compartments, and in the spinal region. Primary diffuse leptomeningeal gliomatosis was diagnosed by a meningeal biopsy.

Use of buddy wire to facilitate Y-configured stent placement in middle cerebral artery bifurcation aneurysms with daughter branches arising from the sac: a technical note

BACKGROUND AND IMPORTANCE

Endovascular treatment of geometrically complex bifurcation aneurysms using a standard Y-configured stenting technique might be extremely difficult, particularly in aneurysms with daughter branches that acutely arise from the aneurysm sac itself. In those cases, deployment of the second stent through interstices of the first stent could be troublesome because of untoward angular changes in the vascular bifurcation prompted by angular changes resulting from placement of the first stent. Here, we describe a novel application of the buddy wire technique to facilitate Y-configured stenting in middle cerebral artery (MCA) bifurcation aneurysms with unfavorable anatomic configuration.

CLINICAL PRESENTATION

A 60-year-old man with a left-sided MCA bifurcation aneurysm was treated using the buddy wire technique. In addition to the standard Y-configured stenting procedure, we also inserted a 0.014-inch exchange microguidewire into the superior daughter branch, which more acutely emanated from the sac, to attain a favorable bifurcation configuration before deployment of the stents in the Y configuration. The new technique was successful, and the postprocedural course of the treatment was uneventful.

CONCLUSION

Use of a buddy wire in MCA bifurcation aneurysms with unfavorable anatomic configurations may be a promising method to facilitate Y-configured stent placement.

Flow Re-direction Endoluminal Device in treatment of cerebral aneurysms: initial experience with short-term follow-up results

Object

Flow diverter (FD) stents are relatively new and important devices in the treatment of cerebral aneurysms. The Flow Re-Direction Endoluminal Device has been recently released for clinical use. The authors' aim in this paper is to report their initial single-center FRED experience with short-term results.

Methods

Between February 2012 and May 2013, 33 patients with 37 aneurysms (35 unruptured and 2 previously ruptured aneurysms) were treated with the FRED. Clinical and radiological data of the patients were retrospectively reviewed.

Results

In all patients only 1 device was used without any additional device or material, such as a stent or coil. All procedures were successfully performed. The procedural complication rate was 3% (1 of 33). Thirty patients underwent clinical and radiological follow-up. During the follow-up period, changes in stent morphology, such as “fish mouth” and “foreshortening” phenomena, occurred in 5 patients. The mortality and permanent morbidity rates were 0%. The complete occlusion rates were 32% (6 of 19) at 0–1 month, 67% (8 of 12) at 2–3 months, 80% (4 of 5) at 4–6 months, and 100% (8 of 8) at 7–12 months. The rates for some aneurysms were assessed at more than one time point.

Conclusions

The FRED has an ability to serve neurointerventionalists in the treatment of cerebral aneurysms with its different technical advantages. The occlusion rates with FRED are similar to those with other FD devices. However, these short-term results need to be confirmed with mid- and long-term follow-up results of multicenter large series.