Predicting a Favorable (mRS 0-2) or Unfavorable (mRS 3-6) Stroke Outcome by Arterial Spin Labeling and Amide Proton Transfer Imaging in Post-Thrombolysis Stroke Patients.

(1) Background: The objective of this study was to determine whether arterial spin labeling (ASL), amide proton transfer (APT), or their combination could distinguish between patients with a low and high modified Rankin Scale (mRS) and forecast the effectiveness of the therapy; (2) Methods: Fifty-eight patients with subacute phase ischemic stroke were included in this study. Based on cerebral blood flow (CBF) and asymmetry magnetic transfer ratio (MTRasym) images, histogram analysis was performed on the ischemic area to acquire imaging biomarkers, and the contralateral area was used as a control. Imaging biomarkers were compared between the low (mRS 0-2) and high (mRS 3-6) mRS score groups using the Mann-Whitney U test. Receiver operating characteristic (ROC) curve analysis was used to evaluate the performance of the potential biomarkers in differentiating between the two groups; (3) Results: The rAPT 50th had an area under the ROC curve (AUC) of 0.728, with a sensitivity of 91.67% and a specificity of 61.76% for differentiating between patients with low and high mRS scores. Moreover, the AUC, sensitivity, and specificity of the rASL max were 0.926, 100%, and 82.4%, respectively. Combining the parameters with logistic regression could further improve the performance in predicting prognosis, leading to an AUC of 0.968, a sensitivity of 100%, and a specificity of 91.2%; (4) Conclusions: The combination of APT and ASL may be a potential imaging biomarker to reflect the effectiveness of thrombolytic therapy for stroke patients, assisting in guiding treatment approaches and identifying high-risk patients such as those with severe disability, paralysis, and cognitive impairment.

Cerebral perfusion alterations in patients with trigeminal neuralgia as measured by pseudo-continuous arterial spin labeling.

Background: Accumulating evidence suggests that trigeminal neuralgia (TN) causes structural and functional alterations in the brain. However, only a few studies have focused on cerebral blood flow (CBF) changes in patients with TN. This study aimed to explore whether altered cerebral perfusion patterns exist in patients with TN and investigate the relationship between abnormal regional CBF (rCBF) and clinical characteristics of TN. Materials and methods: This study included 28 patients with TN and 30 age- and sex-matched healthy controls (HCs) who underwent perfusion functional MRI (fMRI) of the brain using pseudo-continuous arterial spin labeling (pCASL) in the resting state. The regions of significantly altered CBF in patients with TN were detected using group comparison analyses. Then, the relationships between the clinical characteristics and abnormal rCBF were further investigated. Results: Compared to the control group, patients with TN exhibited increased rCBF, primarily in the thalamus, middle frontal gyrus (MFG), and left insula. Furthermore, the CBF values of the thalamus were negatively correlated with the pain intensity of TN and positively correlated with pain duration in patients with TN. Conclusion: Primary alterations in rCBF in patients with TN occurred in different brain regions related to pain, which are involved in cognitive-affective interaction, pain perception, and pain modulation. These results indicate that non-invasive resting cerebral perfusion imaging may contribute complementary information to further understanding the neuropathological mechanism underlying TN.

Flatness of the Meckel cave may cause primary trigeminal neuralgia: a radiomics-based study.

BACKGROUND: Neurovascular contact (NVC) is the main cause of primary trigeminal neuralgia (PTN); however, cases of PTN without NVC are still observed. In this study, the Meckel cave (MC) morphology in PTN were analyzed by radiomics and compared to healthy controls (HCs) to explore the cause of PTN. METHODS: We studied the 3.0T MRI data of 115 patients with PTN and 46 HCs. Bilateral MC was modeled using the 3D Slicer software, and the morphological characteristics of MC were analyzed using the radiomics method. RESULTS: The right side incidence rate in the PTN group was higher than the left side incidence. By analyzing the flatness feature of MC, we observed that the affected side of the PTN was lower than that of the unaffected side, the right MC of the PTN and HC was lower than that of the left MC, the MC of the affected side of the left and right PTN without bilateral NVC was lower than that of the unaffected side. CONCLUSIONS: By providing a method to analyze the morphology of the MC, we found that there is an asymmetry in the morphology of bilateral MC in the PTN and HC groups. It can be inferred that the flatness of the MC may be a cause of PTN.

Cortical thickness, gyrification and sulcal depth in trigeminal neuralgia.

Neuroimaging studies have documented brain structural alterations induced by chronic pain, particularly in gray matter volume. However, the effects of trigeminal neuralgia (TN), a severe paroxysmal pain disorder, on cortical morphology are not yet known. In this study, we recruited 30 TN patients and 30 age-, and gender-matched healthy controls (HCs). Using Computational Anatomy Toolbox (CAT12), we calculated and compared group differences in cortical thickness, gyrification, and sulcal depth with two-sample t tests (p < 0.05, multiple comparison corrected). Relationships between altered cortical characteristics and pain intensity were investigated with correlation analysis. Compared to HCs, TN patients exhibited significantly decreased cortical thickness in the left inferior frontal, and left medial orbitofrontal cortex; decreased gyrification in the left superior frontal cortex; and decreased sulcal depth in the bilateral superior frontal (extending to anterior cingulate) cortex. In addition, we found significantly negative correlations between the mean cortical thickness in left medial orbitofrontal cortex and pain intensity, and between the mean gyrification in left superior frontal cortex and pain intensity. Chronic pain may be associated with abnormal cortical thickness, gyrification and sulcal depth in trigeminal neuralgia. These morphological changes might contribute to understand the underlying neurobiological mechanism of trigeminal neuralgia.

Association of Reduced Tract Integrity with Social Communication Deficits in Preschool Autism Children: A Tract-Based Spatial Statistics Study.

PURPOSE: To analyze the changes in white matter tracts in preschool children with autism spectrum disorder (ASD), and the correlation between these changes and social communication deficits. METHODS: Diffuse tensor imaging was used to assess white matter integrity using tract-based spatial statistics in a sample of 50 right-handed children with ASD aged 2-6 years vis a reference sample of 46 typically developing children aged 2-6 years. We then correlated these significant different fiber tracts between groups with communication and social interaction scores using the Autism Diagnostic Interview-Revised Assessment (ADI-R) Scale. RESULTS: We observed decreased fractional anisotropy (FA) in tracts including the left superior longitudinal fasciculus (SLF), the splenium of the corpus callosum (splCC), the left corticospinal tracts, and the left inferior longitudinal fasciculus (ILF) in children with ASD. Specifically, there was reduced white matter integrity of these tracts in the left cerebral hemisphere. In addition, we found that the decreased FA of left SLF and ILF was negatively associated with the ADI-R scores in children with ASD. CONCLUSION: The structural integrity of some white matter tracts in the five-level anatomical model for the social communication was reduced. The reduced integrity white matter that we observed primarily in the left cerebral hemisphere may be a neural substrate of social communication deficits in preschool children with ASD, and we speculate that the reduction is associated with the severity of social interaction. The reduced FA of the splCC might be a substantial biomarker for children with ASD.

Functional connectome-based biomarkers predict chronic codeine-containing cough syrup dependent.

PURPOSE: Codeine-containing cough syrup (CCS) is considered among the most popular drugs of abuse in adolescents worldwide. Accurate prediction and identification of CCS dependent (CCSD) users are crucial. This study aimed to identify a brain-connectome-based predictor of CCSD using a machine learning model based on a ten-fold cross-validation logistic regression (LR) classifier. METHODS: 40 CCSD users and 40 healthy control (HC) subjects underwent functional magnetic resonance imaging to construct weight functional networks. Partial correlation analysis was used to analyze relations between abnormal network metrics and clinical characteristics (BIS total scores, CCS abuse duration, and mean CCS dose) in CCSD. A ten-fold cross-validation LR classifier was used to classify CCSD users and HC subjects. RESULTS: The CCSD group showed significantly abnormal nodes and connections in the right posterior cingulate, right middle insula, bilateral prefrontal cortex, parietal lobe, temporal lobe, occipital lobe, and cerebellum. Furthermore, higher characteristic path length and lower clustering coefficient (Cp), global efficiency, and local efficiency (Eloc) were observed in the global topologies in CCSD. The abnormal global properties (Cp and Eloc) and node properties of the prefrontal cortex were significantly correlated with clinical characteristics (BIS-11 scores, CCS abuse duration) in CCSD. The LR classifier models demonstrated accuracy, sensitivity, specificity, precision, and AUC of 82.5%, 82.5%, 82.5%, 76.8%, and 82.5%. CONCLUSIONS: These data demonstrate that abnormal functional connectome may be closely linked to clinical characteristics in CCSD. Functional connectome-based biomarkers can be a powerful tool for personalized diagnosis of CCSD in the future.

Applying Amide Proton Transfer-Weighted Imaging (APTWI) to Distinguish Papillary Thyroid Carcinomas and Predominantly Solid Adenomatous Nodules: Comparison With Diffusion-Weighted Imaging.

Background: Amide proton transfer-weighted (ATPw) imaging is a novel MRI technique that has been used to identify benign and malignant tumors. The present study evaluated the role of APTw imaging in differentiating papillary thyroid carcinoma from predominantly solid adenomatous nodule. Methods: This study included 24 cases of solitary papillary thyroid carcinoma, and 20 cases of solid adenomatous nodules. Normal thyroid tissues were examined in 12 healthy subjects. The healthy subjects, eight cases of adenomatous nodule with cystic degeneration, and 12 cases of thyroid goiter, were only considered in the descriptive analysis, not included in our statistical analysis. The mean APTw value and the apparent diffusion coefficients (ADCs) of papillary thyroid carcinoma and solid adenomatous nodule were compared via a Mann-Whitney U test and receiver operating characteristic (ROC)-curve analyses. Results: The adenomatous nodule (3.3 ± 1.3%) exhibited significantly higher APTw value (p < 0.05) than that of the papillary thyroid carcinoma (1.8 ± 0.7%). The optimal cut-off value of the mean APTw value in differentiating papillary thyroid carcinoma from adenomatous nodule was 3.15%, with a sensitivity of 60% and a specificity of 100%. The mean ADC of papillary thyroid carcinoma (1.2 ± 0.2 × 10-3 mm2/s) was significantly lower than that of adenomatous nodule (2.0 ± 0.4 × 10-3 mm2/s). The optimal cut-off value of the mean ADC was 1.35 × 10-3 mm2/s, with a sensitivity of 100% and a specificity of 75%. Based on the ROC-curve analysis of APT and ADC, the ADC showed a higher area under the curve (AUC) than that of APT (AUCAPT = 0.84, AUCADC = 0.95). Conclusion: APTw imaging may be as useful as DWI for the differentiation of papillary thyroid carcinoma from predominantly solid adenomatous nodule. Although the sensitivity of ADC was greater than that of APT, APT had greater specificity.

Alterations of Dynamic Regional Homogeneity in Trigeminal Neuralgia: A Resting-State fMRI Study.

Accumulating evidence from neuroimaging studies has supported that chronic pain could induce changes in brain function. However, few studies have focused on the dynamic regional homogeneity (dReHo) of trigeminal neuralgia (TN). In this study, twenty-eight TN patients and 28 healthy controls (HC) were included. Based on the resting-state fMRI (rsfMRI), we detected abnormalities in dReHo in the TN patients. Patients with TN had decreased dReHo in the left middle temporal gyrus, superior parietal lobule, and precentral gyrus, and increased dReHo in the thalamus. Furthermore, the increase in dReHo in the thalamus was positively correlated with duration of TN (r = 0.485, p = 0.012). These results provide compelling evidence for abnormal resting-state brain activity in TN and suggest that the duration of TN may play a critical role in brain function.

Abnormal Topology of the Structural Connectome in the Limbic Cortico-Basal-Ganglia Circuit and Default-Mode Network Among Primary Insomnia Patients.

Purpose: Primary insomnia (PI) is the second most common mental disorder. However, the topologic alterations in structural brain connectome in patients with PI remain largely unknown. Methods: A total of 44 PI patients and 46 age-, gender-, and education level matched healthy control (HC) participants were recruited in this study. Diffusion tensor imaging (DTI) and resting state MRI were used to construct structural connectome for each participant, and the network parameters were employed by non-parametric permutations to evaluate the significant differences between the two groups. Relationships between abnormal network metrics and clinical characteristics, including the disease duration, the Pittsburgh Sleep Quality Index (PSQI), the Insomnia Severity Index (ISI), the Self-Rating Anxiety Scale (SAS), and the Self-Rating Depression Scale (SDS), were investigated with Spearman's correlation analysis in PI patients. Results: PI patients demonstrated small-world architecture with lower global (P = 0.005) and local (P = 0.035) efficiencies compared with the HC group. The unique hub nodal properties in PI patients were mainly in the right limbic cortico-basal-ganglia circuit. Five disrupted subnetworks in PI patients were observed in the limbic cortico-basal-ganglia circuit and left default-mode networks (DMN) (P < 0.05, NBS corrected). Moreover, most unique hub nodal properties in the right limbic cortico-basal-ganglia circuit were significantly correlated with disease duration, and clinical characteristics (SAS, SDS, ISI scores) in PI processing. Conclusion: These findings suggested the abnormal anatomical network architecture may be closely linked to clinical characteristics in PI. The study provided novel insights into the neural substrates underlying symptoms and neurophysiologic mechanisms of PI.

Reduced White Matter Integrity With Cognitive Impairments in End Stage Renal Disease.

Background: End-stage renal disease (ESRD) is a serious public health problem, which can often lead to multiorgan dysfunction, such as cerebrovascular disease and cognitive damage. It is essential to understand cognitive impairment in patients with ESRD to develop better ESRD treatment and prevent further cognitive impairment. Cognitive impairment is believed to be related to structural abnormalities in the brain. Purpose: To investigate white matter microstructural abnormalities in patients with ESRD using TBSS analysis of DTI and to explore the possible mechanisms underlying the impaired cognitive function. Materials and Methods: A TBSS analysis of DTI data was to investigate the microstructural changes in their WM over the whole brain. We chose the white matter tracts or regions with significantly reduced FA as the regions of interest (ROIs), Pearson's correlations were performed between clinical indicators (Mini-Mental State Examination (MMSE), digit span task scores, serum creatinine, blood urea nitrogen and hemodialysis duration) and the mean FA value of the ROIs in the ESRD patients. Results: Lower FA and higher MD, AD and RD values were observed in widespread and symmetrical WM in ESRD patients than healthy controls (HCs), Pearson correlation analysis revealed a significantly positive correlation between the Mini-Mental State Examination (MMSE) scores and FA values in the right corona radiata and left anterior thalamic radiation (ATR) and demonstrated a significantly negative correlation between FA values and the serum creatinine and blood urea nitrogen in the ATR (P < 0.01) in addition, digit span task scores positively correlate with the FA value in the left anterior rather than in the corona radiata. No cluster survived when we adopted the False Discovery Rate (FDR) correction to multiple comparisons. Conclusion: Our study indicate widespread impairment of the white matter in ESRD patients. Damage to the thalamic radiation and corona radiata may affect cognitive function in ESRD patients, the reduced integrity of ATR may tend to affect the working memory while the damage to the corona radiata may involve the executive function impaired in ESRD patients. The accumulation of serum creatinine and blood urea nitrogen may contribute to the WM impairment.

Altered gray matter volume in primary insomnia patients: a DARTEL-VBM study.

Previous neuroimaging studies have reported brain morphological alterations and the occurrence of mental disorders in primary insomnia (PI) patients. However, studies of the effect of disrupted sleep on brain structure have showed inconsistent results. In this study, DARTEL-VBM was used to evaluate the changes in gray matter volume from 60 PI patients and 53 controls. Voxel-wise statistics was performed in two ways. One is a more liberal statistical analysis using an uncorrected P < 0. 001 with 25 voxels, and the other one is a more conservative approach using a threshold of P < 0.05, corrected for multiple comparisons using the Gaussian random field (GRF) method. Partial correlation was used to analyze the relationship between abnormal volume and clinical features. PI patients had reduced gray matter volume primarily in the right middle cingulate cortex with correction (P < 0.05). Correlation analysis showed gray matter changes in the left middle cingulate cortex were negatively associated with self-ratings for anxiety and depression. This study showed that gray matter deficits in cingulate cortex in patients with insomnia, and the decreased gray matter volume may be associated with the difficulties in emotional management due to insomnia. Functional roles of the affected regions in emotion and regulation of sleep might provide supplementary evidence and guide further research that may facilitate understanding the mechanisms underlying insomnia.

Non-invasive Amide Proton Transfer Imaging and ZOOM Diffusion-Weighted Imaging in Differentiating Benign and Malignant Thyroid Micronodules.

Background: Pre-operative non-invasive differentiation of benign and malignant thyroid nodules is difficult for doctors. This study aims to determine whether amide proton transfer (APT) imaging and zonally oblique multi-slice (ZOOM) diffusion-weighted imaging (DWI) can provide increased accuracy in differentiating benign and malignant thyroid nodules. Methods: This retrospective study was approved by the institutional review board and included 60 thyroid nodules in 50 patients. All of the nodules were classified as malignant (n = 21) or benign (n = 39) based on pathology. It was meaningful to analyze the APT and apparent diffusion coefficient (ADC) values of the two groups by independent t-test to identify the benign and malignant thyroid nodules. The relationship between APT and ZOOM DWI was explored through Pearson correlation analysis. The diagnostic efficacy of APT and ZOOM DWI in determining if thyroid nodules were benign or malignant was compared using receiver operating characteristic (ROC) curve analysis. Results: The mean APTw value of the benign nodules was 2.99 ± 0.79, while that of the malignant nodules was 2.14 ± 0.73. Additionally, there was a significant difference in the APTw values of the two groups (P < 0.05). The mean ADC value of the benign nodules was 1.84 ± 0.41, and was significantly different from that of the malignant nodules, which was 1.21 ± 0.19 (P < 0.05). Scatter point and Pearson test showed a moderate positive correlation between the APT and ADC values (P < 0.05). The ROC curve showed that the area under the curve (AUC) value of ZOOM DWI (AUC = 0.937) was greater than that of APT (AUC = 0.783) (P = 0.028). Conclusion: APT and ZOOM DWI imaging improved the accuracy of distinguishing between benign and malignant thyroid nodules. ZOOM DWI is superior to APTw imaging (Z = 2.198, P < 0.05).

Increased insular connectivity with emotional regions in primary insomnia patients: a resting-state fMRI study.

OBJECTIVE: To explore the abnormal connectivity patterns between the insular and the voxels of the brain in primary insomnia (PI) with insular-based functional connectivity (FC). METHODS: With the resting-state fMRI data acquired from 57 PI patients and 46 healthy controls, a two-sample t test was performed on individual FC correlation maps from two groups. The person correlation analysis was used to evaluate the relationship between the abnormal FC and clinical features. RESULTS: PI patients show enhanced connectivity between the left insula with the right anterior cingulate cortex (p < 0.05 and p < 0.001, AlphaSim-corrected), right frontal sup orb, bilateral thalamus and left precuneus,as well as decreased connectivity with the left middle temporal gyrus and right fusiform (p < 0.05, AlphaSim-corrected). Correlation analysis indicated the enhanced connectivities in the PI patients have significant negative correlations with Self-Rating Depression Scale(SDS)and Self-Rating Anxiety Scale(SAS)scores. In addition, the decreased functional connectivities showed positive correlations with SDS and SAS scores. CONCLUSION: Our study showed the increased connectivity regions with insula were mainly in the emotional circle and decreased connectivity was in cognitive-related regions. These provide additional evidence from functional integration view to understand the possible underlying neural- mechanisms of PI. KEY POINTS: • The aberrant insular-based connectivity pattern of PI patients was detected. • Regions showing increased connectivity with left insular were mainly in emotional circle. • Significant correlations between changed FC and SDS and SAS score were found.

Reduced volume of gray matter in patients with trigeminal neuralgia.

Accumulating evidence from brain structural imaging studies has supported that chronic pain could induce changes in brain gray matter volume. However, few studies have focused on the gray matter alterations of Trigeminal neuralgia (TN). In this study, twenty-eight TN patients (thirteen females; mean age, 45.86 years ±11.17) and 28 healthy controls (HC; thirteen females; mean age, 44.89 years ±7.67) were included. Using voxel-based morphometry (VBM), we detected abnormalities in gray matter volume in the TN patients. Based on a voxel-wise analysis, the TN group showed significantly decreased gray matter volume in the bilateral superior/middle temporal gyrus (STG/MTG), bilateral parahippocampus, left anterior cingulate cortex (ACC), caudate nucleus, right fusiform gyrus, and right cerebellum compared with the HC. In addition, we found that the gray matter volume in the bilateral STG/MTG was negatively correlated with the duration of TN. These results provide compelling evidence for gray matter abnormalities in TN and suggest that the duration of TN may be a critical factor associated with brain alterations.

Altered white matter microstructure identified with tract-based spatial statistics in irritable bowel syndrome: a diffusion tensor imaging study.

The neural mechanisms underlying the pathophysiology of irritable bowel syndrome(IBS) are far from being completely understood. The purpose of the present study was to investigate potential white matter (WM) microstructural changes and underlying causes for WM impairment in IBS using diffusion tensor imaging. The present prospective study involved 19 patients with IBS and 20 healthy controls. Whole-brain voxel-wise analyses of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were performed by tract-based spatial statistics (TBSS) to localize abnormal WM regions between the 2 groups. We found that IBS patients had significantly reduced FA (P < 0.05) in the splenium of the corpus callosum, the right retrolenticular area of the internal capsule and the right superior corona radiata. We also found increased MD (P < 0.05) in the splenium and body of the corpus callosum, the right retrolenticular area of the internal capsule, the right superior corona radiata and the right posterior limb of the internal capsule. In addition, IBS patients had significantly increased AD (P < 0.05) in the splenium of the corpus callosum, the bilateral retrolenticular area of the internal capsule and the left posterior limb of the internal capsule. We conclude that the WM microstructure is changed in IBS and the underlying pathological basis may be attributed to the axonal injury and loss. These results may lead to a better understanding of the pathophysiology of IBS.

[Structural changes in the gray matter in patients with trigeminal neuralgia: a voxel-based morphometric study].

OBJECTIVE: To investigate the changes in whole brain gray matter volume in patients with trigeminal neuralgia using voxel-based morphometry (VBM). METHODS: Twenty-eight patients with trigeminal neuralgia and 28 healthy controls underwent magnetic resonance imaging with a Philips 1.5T MRI scanner. VBM was used to compare the structural differences in the whole brain gray matter between the two groups based on the DARTEL after data preprocessing with SPM8 software package. RESULTS: Compared with the healthy controls, the patients with trigeminal neuralgia presented with decreased gray matter volume in several brain regions including the bilateral middle temporal gyrus, bilateral superior/middle frontal gyrus, left pre-/post-central gyrus, right fusiform and anterior cingulate gyrus. CONCLUSIONS: Patients with trigeminal neuralgia had abnormal gray matter volume in some brain regions associated with perception and processing of pain sensation. These changes may provide clues for further exploration of the neuropathogenic basis of trigeminal neuralgia.

[Anatomic study of the facial artery using multislice spiral CT angiography].

OBJECTIVE: To study the anatomy of the facial artery using 16-slice spiral CT angiography (CTA). METHODS: Forty-five patients without vascular pathologies or other anomalies underwent 16-slice spiral CT angiography after injection of 350 mg I/ml Omnipaque through the ulnar vein. MIP and volume rendering of the images were performed to analyze the left and right facial artery. RESULTS: The left facial artery arose from the external carotid artery with the distances from the carotid artery bifurcation of 4.5-47.90 mm (mean 18.77-/+8.98 mm), and in 1 case (2.2%), the artery arose from the common carotid artery. The right facial artery arose from the external carotid artery in all the 45 cases (100%) with distances from the carotid artery bifurcation of 6.8-39.70 mm (mean 19.23-/+8.25 mm). The bilateral facial arteries more commonly arose from the external carotid artery independently, and the lingual artery and facial artery sharing the same trunk arising from the external carotid artery was less common. In 1 case, the left facial artery and the submental artery shared the same trunk, and in another case, the left facial artery, thyroid artery and lingual artery shared the same trunk. The diameter of the left facial artery ranged from 1.40 to 4.70 mm (mean 2.83-/+0.77 mm), and that of the right facial artery was 1.60-4.30 mm (mean 2.81-/+0.79 mm). The left facial artery ended below the angle of the mouth in 12 cases (26.67%), between the angle of the mouth and the nasal wing in 7 cases (15.56%), and above the nasal wing in 26 cases (57.77%). The right facial artery ended below the angle of the mouth in 7 cases (15.56%), between the angle of the mouth and the nasal wing in 12 cases (26.67%), and above the nasal wing in 26 cases (57.77%). The bilateral facial arteries frequently passed through the submandibular gland parenchyma (23 cases on the left and 24 cases on the right), and the facial arteries were found occasionally to run below the submandibular gland (11 cases on the left and 9 on the right). CONCLUSION: 16-slice spiral CT angiography can help in preoperative facial artery evaluation noninvasively. This modality can clearly display the bilateral facial arteries, including their origin, course, distribution and ending to provide detailed information for flap designing before plastic surgery and for preoperative evaluation for microvascular surgery.