Three-dimensional morphological analysis of intracranial aneurysms: A fully automated method for aneurysm sac isolation and quantification

The choroid provides nutritional support for the retinal pigment epithelium and photoreceptors. Choroidal dysfunction plays a major role in several of the most important causes of vision loss including age-related macular degeneration, myopic degeneration, and pachychoroid diseases such as central serous chorioretinopathy and polypoidal choroidal vasculopathy. We describe an imaging technique using depth-resolved swept-source optical coherence tomography (SS-OCT) that provides full-thickness three-dimensional (3D) visualization of choroidal anatomy including topographical features of individual vessels. Enrolled subjects with different clinical manifestations within the pachychoroid disease spectrum underwent 15 mm × 9 mm volume scans centered on the fovea. A fully automated method segmented the choroidal vessels using their hyporeflective lumens. Binarized choroidal vessels were rendered in a 3D viewer as a vascular network within a choroidal slab. The network of choroidal vessels was color depth-encoded with a reference to the Bruch’s membrane segmentation. Topographical features of the choroidal vasculature were characterized and compared with choroidal imaging obtained with indocyanine green angiography (ICGA) from the same subject. The en face SS-OCT projections of the larger choroid vessels closely resembled to that obtained with ICGA, with the automated SS-OCT approach proving additional depth-encoded 3D information. In 16 eyes with pachychoroid disease, the SS-OCT approach added clinically relevant structural details, including choroidal thickness and vessel depth, which the ICGA studies could not provide. Our technique appears to advance the in vivo visualization of the full-thickness choroid, successfully reveals the topographical features of choroidal vasculature, and shows potential for further quantitative analysis when compared with other choroidal imaging techniques. This improved visualization of choroidal vasculature and its 3D structure should provide an insight into choroid-related disease mechanisms as well as their responses to treatment.

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Detection of clustered anomalies in single-voxel morphometry as a rapid automated method for identifying intracranial aneurysms

Computerized Medical Imaging and Graphics ◽

10.1016/j.compmedimag.2021.101888 ◽

2021 ◽

Vol 89 ◽

pp. 101888

Author(s):

Mark C. Allenby ◽

Ee Shern Liang ◽

James Harvey ◽

Maria A. Woodruff ◽

Marita Prior ◽

...

Keyword(s):

Intracranial Aneurysms ◽

Automated Method ◽

Single Voxel

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Automated Segmentation of Infarct Lesions in T1-Weighted MRI Scans Using Variational Mode Decomposition and Deep Learning

Sensors ◽

10.3390/s21061952 ◽

2021 ◽

Vol 21 (6) ◽

pp. 1952

Author(s):

May Phu Paing ◽

Supan Tungjitkusolmun ◽

Toan Huy Bui ◽

Sarinporn Visitsattapongse ◽

Chuchart Pintavirooj

Keyword(s):

Deep Learning ◽

Brain Infarction ◽

Three Dimensional ◽

Dice Similarity Coefficient ◽

Automated Segmentation ◽

Variational Mode Decomposition ◽

Brain Scans ◽

Automated Method ◽

Mode Decomposition ◽

Segmentation Task

Automated segmentation methods are critical for early detection, prompt actions, and immediate treatments in reducing disability and death risks of brain infarction. This paper aims to develop a fully automated method to segment the infarct lesions from T1-weighted brain scans. As a key novelty, the proposed method combines variational mode decomposition and deep learning-based segmentation to take advantages of both methods and provide better results. There are three main technical contributions in this paper. First, variational mode decomposition is applied as a pre-processing to discriminate the infarct lesions from unwanted non-infarct tissues. Second, overlapped patches strategy is proposed to reduce the workload of the deep-learning-based segmentation task. Finally, a three-dimensional U-Net model is developed to perform patch-wise segmentation of infarct lesions. A total of 239 brain scans from a public dataset is utilized to develop and evaluate the proposed method. Empirical results reveal that the proposed automated segmentation can provide promising performances with an average dice similarity coefficient (DSC) of 0.6684, intersection over union (IoU) of 0.5022, and average symmetric surface distance (ASSD) of 0.3932, respectively.

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Three-dimensional morphological analysis of neocondyle bone growth after fibula free flap reconstruction

International Journal of Oral and Maxillofacial Surgery ◽

10.1016/j.ijom.2021.03.005 ◽

2021 ◽

Author(s):

Y. Yu ◽

H.Y. Soh ◽

S. Bai ◽

W.-B. Zhang ◽

Y. Wang ◽

...

Keyword(s):

Free Flap ◽

Morphological Analysis ◽

Bone Growth ◽

Three Dimensional ◽

Flap Reconstruction ◽

Free Flap Reconstruction ◽

Fibula Free Flap

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Semiautomated 3D mapping of aneurysmal wall enhancement with 7T-MRI

Scientific Reports ◽

10.1038/s41598-021-97727-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ashrita Raghuram ◽

Alberto Varon ◽

Jorge A. Roa ◽

Daizo Ishii ◽

Yongjun Lu ◽

...

Keyword(s):

Intracranial Aneurysms ◽

3D Imaging ◽

High Resolution Imaging ◽

Biological Processes ◽

Automated Method ◽

Aneurysm Wall ◽

Unruptured Intracranial Aneurysms ◽

Potential Biomarker ◽

Resolution Imaging ◽

Objective Tool

AbstractAneurysm wall enhancement (AWE) after the administration of contrast gadolinium is a potential biomarker of unstable intracranial aneurysms. While most studies determine AWE subjectively, this study comprehensively quantified AWE in 3D imaging using a semi-automated method. Thirty patients with 33 unruptured intracranial aneurysms prospectively underwent high-resolution imaging with 7T-MRI. The signal intensity (SI) of the aneurysm wall was mapped and normalized to the pituitary stalk (PS) and corpus callosum (CC). The CC proved to be a more reliable normalizing structure in detecting contrast enhancement (p < 0.0001). 3D-heatmaps and histogram analysis of AWE were used to generate the following metrics: specific aneurysm wall enhancement (SAWE), general aneurysm wall enhancement (GAWE) and focal aneurysm wall enhancement (FAWE). GAWE was more accurate in detecting known morphological determinants of aneurysm instability such as size ≥ 7 mm (p = 0.049), size ratio (p = 0.01) and aspect ratio (p = 0.002). SAWE and FAWE were aneurysm specific metrics used to characterize enhancement patterns within the aneurysm wall and the distribution of enhancement along the aneurysm. Blebs were easily identified on 3D-heatmaps and were more enhancing than aneurysm sacs (p = 0.0017). 3D-AWE mapping may be a powerful objective tool in characterizing different biological processes of the aneurysm wall.

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Detection of the Residual Lumen of Intracranial Aneurysms Immediately after Coil Embolization by Three-dimensional Digital Subtraction Angiographic Virtual Endoscopic Imaging

Neurosurgery ◽

10.1097/00006123-200203000-00008 ◽

2002 ◽

Vol 50 (3) ◽

pp. 476-485 ◽

Cited By ~ 1

Author(s):

Hiro Kiyosue ◽

Mika Okahara ◽

Shuichi Tanoue ◽

Takaharu Nakamura ◽

Hirofumi Nagatomi ◽

...

Keyword(s):

Coil Embolization ◽

Intracranial Aneurysms ◽

Cerebral Arteries ◽

Three Dimensional ◽

Digital Subtraction ◽

Aneurysm Volume ◽

Digital Subtraction Angiographic ◽

Incomplete Occlusion ◽

Coil Volume

Abstract OBJECTIVE: Detection of a small residual lumen after coil embolization is often difficult because of the coil mass and the overlap of the cerebral arteries. The purpose of this study was to assess the usefulness of virtual endoscopic (VE) analysis of three-dimensional digital subtraction angiographic (DSA) images for evaluation of aneurysmal occlusion immediately after the procedure. METHODS: Twenty-seven intracranial aneurysms were treated with coil embolization using a three-dimensional DSA system. Biplane and rotational DSA scanning was performed before and immediately after the procedures. VE images were obtained at a separate workstation, after transfer of the rotational images. Two-dimensional (2D) DSA images and VE images obtained after the procedure were assessed with respect to aneurysmal occlusion. Morphological outcomes and other factors, including location, size, volumetric ratio (coil volume/aneurysm volume), and residual sites, were also evaluated. RESULTS: Seven aneurysms were evaluated as complete occlusion (CO) on both 2D DSA images and VE images. Twelve aneurysms exhibited residual lumina on both 2D DSA images and VE images. Five aneurysms were evaluated as CO on 2D DSA images and as incomplete occlusion on VE images. There were no recurrences among the aneurysms that were evaluated as CO on VE images. Two of five aneurysms that were evaluated as CO on 2D DSA images and as incomplete occlusion on VE images demonstrated regrowth in follow-up examinations. Residual sites and volumetric ratios were correlated with aneurysmal regrowth. CONCLUSION: VE imaging can demonstrate a residual lumen more frequently than can 2D DSA imaging and is useful for evaluating aneurysmal occlusion after coil embolization.

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Three-dimensional Morphological Analysis of the Upper Lip Configuration during Facial Expressions

Journal of Oral and Maxillofacial Surgery ◽

10.1016/j.joms.2014.06.096 ◽

2014 ◽

Vol 72 (9) ◽

pp. e56

Author(s):

N. Nakamura ◽

E. Nozoe ◽

T. Okawachi ◽

K. Ishihata ◽

K. Shimomatsu ◽

...

Keyword(s):

Facial Expressions ◽

Morphological Analysis ◽

Three Dimensional ◽

Upper Lip

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Embolization of Non-Ruptured Aneurysms

Interventional Neuroradiology ◽

10.1177/15910199990050s117 ◽

1999 ◽

Vol 5 (1_suppl) ◽

pp. 93-96 ◽

Cited By ~ 1

Author(s):

C.F. Dowd ◽

C.C. Phatouros ◽

A.M. Malek ◽

T.E. Lempert ◽

P.M. Meyers ◽

...

Keyword(s):

Intracranial Aneurysms ◽

Three Dimensional ◽

Giant Aneurysm ◽

Epidemiological Data ◽

Anterior Circulation ◽

Unruptured Aneurysms ◽

Aneurysm Neck ◽

Technical Developments ◽

History Of ◽

Anterior Circulation Aneurysms

Options for treatment of intracranial aneurysms have expanded with the advent of the Guglielmi Detachable Cod (GDC) eight years ago. We have reviewed 435 cases of intracranial aneurysms treated at UCSF by endovascular means using the GDC system. Of these, 55% represent anterior circulation aneurysms, and 45% are located in the posterior circulation. Additionally, 55% of the aneurysms presented with subarachnoid hemorrhage (SAH) and 45% were unruptured. Factors which hindered optimal coiling include the following: wide aneurysm neck in relation to the overall aneurysm size, mural thrombus, giant aneurysm, arteries originating from the aneurysm sac, and middle cerebral location. After initial experience was gained, we tended to avoid these aneurysms especially in the non-ruptured group. This may be especially important in light of new epidemiological data suggesting that the natural history of unruptured aneurysms is significantly lower than previously thought. New technical developments which may reduce the risk of treating unruptured aneurysms include the two-dimensional coil, the three-dimensional coil, the balloon-assist technique for wide-necked aneurysms, and combined stent-coil procedures.

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Three-Dimensional Reconstruction and Numerical Simulation of Intracranial Aneurysm for Sectional Anatomy Based on Computed Tomography Angiography

Journal of Medical Imaging and Health Informatics ◽

10.1166/jmihi.2021.3496 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1957-1962

Author(s):

Xuefei Deng ◽

Yu Liu ◽

Qingling Meng ◽

Danning Cao ◽

Quan Bao ◽

...

Keyword(s):

Computed Tomography ◽

Numerical Simulation ◽

Intracranial Aneurysm ◽

3D Reconstruction ◽

Intracranial Aneurysms ◽

Three Dimensional ◽

Control Group ◽

Observation Group ◽

Intracranial Artery ◽

Sectional Anatomy

Objective: The mortality of rebleeding after ruptured intracranial aneurysms was more than 40%. It is essential to identify the intracranial artery in sectional anatomy. However, it is difficult for students to understand the intracranial artery in the section. Therefore, the purpose of this study is to explore the application effect of three-dimensional (3D) reconstruction and numerical simulation of intracranial aneurysm for sectional anatomy based on computed tomography angiography (CTA). Method: Sixty students in medical imaging specialty of our university were divided into two groups. The control group was taught with conventional sectional anatomy and CT images, while the observation group was taught with 3D reconstruction and numerical simulation of intracranial aneurysm. The teaching characteristics and teaching effects were analyzed and compared between the two groups. Result: The 3D reconstruction can accurately express the size, direction, and adjacent relationship of aneurysms. Through rotation of the 3D image, students can easily understand the name and location of cerebral arteries. Combined with the function of 3D positioning, each blood vessel can automatically and accurately locate in the transverse, coronal, and sagittal plane. Abnormal wall shear stress was easily found in the intersection of cerebral artery circle, which was the physiological basis for the occurrence of aneurysms. There was a high shear zone in the root of an aneurysm, which was the physiological factor of rupture. The scores of sectional specimen identification, drawing examination, and theoretical assessment in the observation group were significantly higher than those in the control group (P < 0.05). Conclusion: The 3D reconstruction and numerical simulation can directly display the 3D morphological and physiological characteristics of intracranial aneurysms, which is convenient for students to understand and memorize. It can reach a good teaching effect in sectional anatomy.

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