OCTA characteristics in non-arteritic central retinal artery occlusion and correlation with visual acuity

AIM:To observe the retinal and choroidal circulations in patients with non-arteritic permanent central retinal artery occlusion(NA-CRAO)via optical coherence tomography angiography(OCTA)and analyze their correlation with visual acuity.METHODS:Sixty-two eyes with clinically confirmed acute NA-CRAO were included in the study and divided into:A type(mild n=29),B type(moderate n=27)and C type(severe n=6)based on the degree of visual loss,retinal edema,and arterial blood flow delay in fundus fluorescence angiography(FFA).Contralateral healthy eyes were used as the control group.Best-corrected visual acuity(BCVA),slit lamp microscopy,indirect ophthalmoscopy,fundus color photography,OCTA,and FFA were performed.Spearman’s correlation analysis was used to determine the correlations between retinal and choroidal vessels and visual acuity.RESULTS:There were no statistically significant differences in age,gender,and intraocular pressure among the three types and the control group(P>0.05).Vessel density in deep capillary plexus(VD-DCP)significantly decreased(P<0.05)in all three types of NA-CRAO patients compared to the control group.Vessel density in superficial vascular plexus(VD-SVP)significantly decreased(P<0.05)in type A patients and choriocapillaris flow area significantly decreased(P<0.05)in type B and type C patients compared to the control group;while outer retinal flow areas significantly increased in the type A(P<0.05)and decreased in type C patients(P<0.05).The retinal thickness significantly increased in type C group(P<0.05).The VD-SVP at fovea in the type A was significantly lower than both of type B and C.The VD-SVP at nasal parafovea in type A and B was significantly lower than type C(P<0.05).The logMAR BCVA of type A was significantly better than that of type B and C groups(P<0.05).Spearman’s correlation analysis showed that the logMAR BCVA was positively correlated with VD-SVP at fovea(r=0.679,P=0.031)and nasal parafovea(r=0.826,P=0.013).CONCLUSION:OCTA is valuable for assessing retinal ischemia,and evaluating visual impairment.Deep retinal vasculature is commonly affected in all NA-CRAO types.VDSVPs at fovea and nasal parafovea can serve as reliable markers of visual impairment in NA-CRAO.

Risk factors of non-arteritic anterior ischaemic optic neuropathy and central retinal artery occlusion

AIM:To investigate the difference in risk factors between non-arteritic anterior ischaemic optic neuropathy(NAION)and central retinal artery occlusion(CRAO)and develop a predictive diagnostic nomogram.METHODS:The study included 37 patients with monocular NAION,20 with monocular CRAO,and 24 with hypertension.Gender,age,and systemic diseases were recorded.Blood routine,lipids,hemorheology,carotid and brachial artery doppler ultrasound,and echocardiography were collected.The optic disc area,cup area,and cup-to-disc ratio(C/D)of the unaffected eye in the NAION and CRAO group and the right eye in the hypertension group were measured.RESULTS:The carotid artery intimal medial thickness(C-IMT)of the affected side of the CRAO group was thicker(P=0.039)and its flow-mediated dilation(FMD)was lower(P=0.049)than the NAION group.Compared with hypertension patients,NAION patients had higher whole blood reduced viscosity low-shear(WBRV-L)and erythrocyte aggregation index(EAI;P=0.045,0.037),and CRAO patients had higher index of rigidity of erythrocyte(IR)and erythrocyte deformation index(EDI;P=0.004,0.001).The optic cup and the C/D of the NAION group were smaller than the other two groups(P<0.0001).The diagnostic prediction model showed high diagnostic specificity(83.7%)and sensitivity(85.6%),which was highly related to hypertension,the C-IMT of the affected side,FMD,platelet(PLT),EAI,and C/D.CONCLUSION:CRAO patients show thicker C-IMT and worse endothelial function than NAION.NAION and CRAO may be related to abnormal hemorheology.A small cup and small C/D may be involved in NAION.The diagnostic nomogram can be used to preliminarily identify NAION and CRAO.

Orbital and sinus rhabdomyosarcoma with concurrent central retinal artery occlusion:A case report

BACKGROUND Both rhabdomyosarcoma(RMS)and central retinal artery occlusion(CRAO)are rare medical diseases,and their simultaneous occurrence in the same patient is extraordinarily uncommon.This study presents a comprehensive overview of the clinical manifestations,diagnostic imaging results,and therapeutic interventions of a patient with both conditions.CASE SUMMARY In this report,we present a 30-year-old male who presented with significant protrusion,pain and vision loss and was diagnosed with RMS in the orbit and sinus with CRAO.Following resection of the sinus and orbital mass and enucleation of the right eye,the patient experienced symptom improvement.CONCLUSION This article provides an in-depth analysis of the patient’s clinical manifestations,the tumor’s anatomical origin,and the etiology of CRAO.The concurrent manifestation of both RMS and CRAO is exceedingly uncommon in clinical practice.

Bilateral Central Retinal Vein Occlusions Combined with Artery Occlusions in A Patient with Acquired Immune Deficiency Syndrome

Purpose: This is the first report of a bilateral nonischemic central retinal vein occlusionscombined with artery occlusions in a patient with acquired immune deficiency syndrome(AIDS). Methods: Case report. Results: A 22-year-old Chinese(male) with a positive human immunodeficiency virus(HIV) infection developed bilateral nonischemic central retinal vein occlusions combinedwith artery occlusions and severe vision loss. The manifestations of the fundus andfluorescein angiography were similar in both eyes.Conclusion: This case report provides the evidences that central retinal vein and arteryocclusions are probably part of the spectrum of AIDS vascular diseases.

Long-term outcomes of anti-VEGF treatment with 5+PRN regimen for macular edema due to central retinal vein occlusion

AIM:To assess the long-term outcomes of treating macular edema(ME)associated with central retinal vein occlusion(CRVO)with a regimen of“5+pro re nata(PRN)”.METHODS:This retrospective study included 27 eyes of 27 patients with ME associated with non-ischemic CRVO(non-iCRVO group,n=15)and ischemic CRVO(iCRVO group,n=12).The eyes were treated with five consecutive intravitreal injections of conbercept or ranibizumab,followed by reinjections as needed or PRN.Retinal laser photocoagulation or intravitreal dexamethasone implants(DEX)were implemented in both groups when necessary.The best-corrected visual acuity(BCVA,logMAR)and central retinal thickness(CRT)were recorded at baseline,at 1,2,3,4,5,6,and 12mo,and at the final visit.The efficacy rates of BCVA and CRT before and after treatment were calculated.The number of injections at each visit and the incidence of adverse events were also recorded.RESULTS:The patients,aged 59.4±15.1y,were followed up for 24.7±8.8mo(range:15-42mo).After treatment,BCVA improved significantly from 1.04±0.56 logMAR at baseline to 0.59±0.36 logMAR(P=0.038)at the final visit in all patients.Both the non-iCRVO and the iCRVO groups achieved improved BCVA compared to the baseline at all visit points,but there was no statistical significance(P=0.197 and 0.33,respectively).The mean CRT was statistically reduced compared to baseline at all visit points in all the eyes and in both groups(all P<0.001).The apparent effective rate was 22.22% for BCVA and 37.04% for CRT after the first injection,48.15%for BCVA and 62.96% for CRT after 5 consecutive injections,and 74.08% for BCVA and 100% for CRT at the end of follow up.The average number of injections in all patients was 9.0±2.4 at 12mo and 14.9±8.1 finally with no statistical significance between both groups(P>0.05).Laser treatment was applied to all eyes in the iCRVO group,while only 5 patients in the noniCRVO group.Six patients in the non-iCRVO group and 3 patients in the iCRVO group had a drug switch.DEX was applied to 4 eyes in the non-iCRVO group and 5 eyes in the iCRVO group.CONCLUSION:The 5+PRN anti-vascular endothelial growth factor(VEGF)regimen is found to be safe and effective for both iCRVO and non-iCRVO,especially in the iCRVO group.The best regimen for such patients needs to be further investigated.Adjuvant laser therapy and DEX are necessary in some cases.

Central Retinal Vein Occlusion in Healthy Young Adults Following COVID-19 Vaccination: Case Series

Our aim is to report 4 cases of central retinal vein occlusion following COVID-19 vaccine administration. In this case series, 4 patients between 23-32 years of age presented to us with unilateral central retinal vein occlusion after 2-15 days of getting vaccinated against COVID-19. One patient was a known case of hypertension and 1 was hypothyroid. All the patients had disc swelling, flame shaped haemorrhages, dilated and tortuous blood vessels in the retina. One patient had cystoid macular edema and was treated with intravitreal ranibizumab. As there were no positive systemic risk factors or incidents, COVID-19 vaccines might have an association with the central retinal vein occlusion in these cases. .

Ocular hypertension in patients with central/hemicentral retinal vein occlusions： cumulative prevalence and management

AIM： To prospectively evaluate the cumulative prevalence and the management of ocular hypertension（OH） in patients with unilateral acute central/hemicentral retinal vein occlusions（C/HCRVOs） over the course of 3 y. METHODS： The study included 57 patients with unilateral acute C/HCRVOs. All patients underwent a comprehensive ophthalmological examination of both eyes. OH associated with C/HCRVO in patients showing a score 〉5% for the risk of conversion to primary open angle glaucoma（POAG） was treated with OH medication. The treatment aimed for a decrease in intraocular pressure（IOP） to 〈21 mm Hg with a 〉22% reduction from the initial values. The cumulative prevalence of OH and the effectiveness of treatment assessed by the cumulative prevalence of conversion from OH to POAG, were estimated. RESULTS： Fifteen patients had OH associated with C/HCRVOs, the cumulative prevalence of OH was 29.4%（95% confidence interval, 16.9-41.9）. The mean value of the risk score of OH conversion to POAG for the 5 subsequent years was 11.7%±5.4%. The IOP significantly decreased from 25.67±2.16 mm Hg to 18.73±2.96 mm Hg. None of the OH patients converted to POAG during the follow-up period. CONCLUSION： The increased cumulative prevalence of OH in C/HCRVO patients indicates that OH is a risk factor for the appearance of venous occlusion. Patients with OH associated with C/HCRVO must be considered to be at high risk for conversion to POAG. Treatment with OH medications prevented conversion to POAG during the 3-year follow-up.

Central retinal artery occlusion and traumatic optic neuropathy following blunt ocular trauma

Dear Editor,We are writing to present a case report of central retinal artery occlusion（CRAO）and traumatic optic neuropathy（TON）with immediate visual loss caused by blunt facial trauma with a soccer ball.CRAO is an ophthalmic emergency with an estimated incidence of 10 in 1 million.

Correlation between obstructive sleep apnea and central retinal vein occlusion

To investigate the possible correlation between obstructive sleep apnea(OSA) and central retinal vein occlusion(CRVO). Thirty consecutive patients with a recent(<3 mo)CRVO and an age-and sex-matched group of 30 control subjects were recruited. All subjects underwent full-night polysomnography to measure apnea-hypopnea index(AHI)and oxygen desaturation index(ODI). The average AHI and ODI were significantly higher in CRVO patients(AHI:13.86±8.63, ODI: 9.21±4.47) than in control subjects(AHI:8.51±6.36, ODI: 5.87±3.18;P=0.008 and 0.001 respectively).Additionally, the AHI was positively correlated with body mass index(BMI;r=0.476, P=0.017) and ODI(r=0.921,P<0.01) in both CRVO and control subjects. According to AHI scores, twenty-two(73.33%) CRVO patients had OSA and 12(40.00%) control subjects had OSA, a difference that was statistically significant(P=0.019). OSA may be a risk factor for or a trigger of CRVO development.

Correlation between macular ganglion cell-inner plexiform layer thickness and visual acuity after resolution of the macular edema secondary to central retinal vein occlusion

AIM： To examine the thickness of the ganglion cell-inner plexiform layer（GCIPL） in eyes with resolved macular edema（ME） in non-ischemic central retinal vein occlusion（CRVO）, applying spectral-domain optical coherence tomography（SD-OCT）, and its relationship with visual acuity.METHODS： The retrospective observational case-control study included 30 eyes of non-ischemic CRVO patients with resolved ME（ME eyes） after treatment, and 30 eyes of non-ischemic CRVO patients without ME（non-ME eyes）. The macular GCIPL thickness, peripapillary retinal nerve fiber layer（p RNFL） thickness and central macular thickness（CMT） were measured on a SD-OCT scan. Linear regression analyses were performed to determine the correlation between the thickness of each and the visual acuity（VA）.RESULTS： No significant difference in average GCIPL thickness, mean pR NFL thickness and CMT were observed between ME group and non-ME group（P=0.296, 0.183, 0.846）. But, minimum GCIPL thickness was reduced in ME eyes compared with non-ME eyes（P=0.022）. Final VA significantly correlated with the minimum GCIPL thickness in ME eyes（r=-0.482, P=0.007）, whereas no correlation was found with average GCIPL thickness, average pR NFL thickness and mean CMT.CONCLUSION： Minimum GCIPL thickness is reduced in ME eyes compared with non-ME eyes, and correlated with the VA in non-ischemic CRVO. These results propose that inner retinal damage occurring in patients with ME secondary to non-ischemic CRVO may lead to permanent visual defect after treatment.

Comment on “Correlation between macular ganglion cell-inner plexiform layer thickness and visual acuity after resolution of the macular edema secondary to centralretinal vein occlusion”

Dear Editor,We would like to address several issues with the study of Kim et a". The study was retrospectively conducted with the existence of a selection bias attributable to inclusion of 2 completely different etiologic subgroups of patients with nonischemic central retinal vein occlusion (CRVO), namely, patients older than 50y, who usually have common systemic conditions such as hypertension and diabetes;and patients younger than 50y, in whom other mechanisms, such as the hyperviscosity syndrome or inflammatory condition, should be specifically considered.

Treatment controversies in a rare case of a simultaneous branch retinal artery and vein occlusion secondary to hyperhomocysteinemia and hypertension

Dear Editor,Combined vascular occlusions involving retinal arteries and veins have been reported in the past. Combined occlusion of the central retinal vein （CRVO） and artery （CRAO）is well described;. Cilioretinal artery occlusion along with CRVO is frequently reported and is well characterized;.

Microvascular changes after conbercept therapy in central retinal vein occlusion analyzed by optical coherence tomography angiography

AIM: To investigate microvascular changes in eyes with central retinal vein occlusion(CRVO) complicated by macular edema before and after intravitreal conbercept injection and evaluate correlations between these changes and best-corrected visual acuity(BCVA) and retinal thickness. METHODS: Twenty-eight eyes of 28 patients with macular edema caused by CRVO were included in this retrospective study. All patients received a single intravitreal conbercept injection to treat macular edema. BCVA and the results of optical coherence tomography angiography(OCTA) automatic measurements of the vessel density in the superficial(SCP) and deep retinal capillary plexus(DCP), the foveal avascular zone(FAZ) area, the FAZ perimeter(PERIM), the vessel density within a 300-μm wide ring surrounding the FAZ(FD-300), the acircularity index(AI), the choriocapillaris flow area, and retinal thickness were recorded before and at one month after treatment and compared with the results observed in age-and sexmatched healthy subjects. RESULTS: The vessel density in the SCP and DCP, the FD-300, and the flow area of the choriocapillaris were allsignificantly lower in CRVO eyes than in healthy eyes, while the AI and retinal thickness were significantly higher(all P<0.05). After treatment, retinal thickness was significantly decreased, and the mean BCVA had markedly improved from 20/167 to 20/65(P=0.0092). The flow area of the choriocapillaris was also significantly improved, which may result from the reduction of shadowing effect caused by the attenuation of macular edema. However, there were no significant changes in SCP and DCP vessel density after treatment. The flow area of the choriocapillaris at baseline was negatively correlated with retinal thickness.CONCLUSION: OCTA enables the non-invasive, layerspecific and quantitative assessment of microvascular changes both before and after treatment, and can therefore be used as a valuable imaging tool for the evaluation of the follow-up in CRVO patients.

Intravitreal injection of bevacizumab alone or with triamcinolone acetonide for treatment of macular edema caused by central retinal vein occlusion

AIM: To compare the efficacy and safety of intravitreal bevacizumab alone versus bevacizumab combined with triamcinolone acetonide in eyes with macular edema caused by central retinal vein occlusion (CRVO) in Chinese patients. METHODS: Seventy-five eyes of 75 patients were enrolled in this prospective, randomized, consecutive study. Thirty-six patients in group 1 were treated with an intravitreal injection of bevacizumab (1.25mg/0.05mL), and 39 patients in group 2 were treated with intravitreal bevacizumab (1.25mg/0.05mL) combined with triamcinolone acetonide (2mg/0.05mL). The main outcomes of the mean best corrected visual acuity (BCVA), central retinal thickness (CRT), and intraocular pressure (IOP) were measured. RESULTS: In group 1, the mean BCVA improved from 37.78 +/- 6.14 (baseline) to 48.06 +/- 3.86, 46.48 +/- 4.77 and 44.18 +/- 5.78 at four, six and twelve weeks post-injection, respectively (P<0.01, P=0.03, P=0.04). In group 2, the mean BCVA improved from 35.92 +/- 6.20 (baseline) to 50.69 +/- 4.22, 48.76 +/- 5.59 and 45.70 +/- 6.56 at the same time points (P<0.01 each). However, there was no significant differences in the mean BCVA (F=0.043, P=0.836) and CRT (F=0.374, P=0.544) between these two groups. During the follow-up, five patients in group 1 and six patients in group 2 with high IOP were controlled with anti-glaucoma drugs. CONCLUSION: Intravitreal injection of bevacizumab alone or combined with triamcinolone acetonide has a short beneficial effect in Chinese patients with macular edema caused by CRVO, but there is no significant difference between the two groups.

Disorganization of the retinal inner layers as a prognostic factor in eyes with central retinal artery occlusion

AIM: To evaluate baseline foveal disorganisation of retinal inner layers(DRIL) as a prognostic factor in eyes with central retinal artery occlusion(CRAO). METHODS: Twenty-eight CRAO patients who were followed-up between 2010 and 2016 were retrospectively investigated. Demographic characteristics and detailed ophthalmological examination findings of all patients were recorded. Macular thicknesses(MTs) from 5 separate spots and DRIL were measured with spectral-domain optic coherence tomography(SD-OCT). Correlations between DRIL score and logMAR converted visual acuity(VA), change in VA, patient reference time(RT), number of hyperbaric oxygen therapy(HBOT) sessions, MT and MT change were investigated.RESULTS: There was a positive correlation between the DRIL score and the final VA(r=0.787) and a negative correlation with the change in VA(r=-0.763). The RT and MT were closely related to the DRIL score. A negative correlation was found between the number of HBOT sessions and the DRIL score(r=-0.341).CONCLUSION: The DRIL score is a parameter assessed by SD-OCT, which can provide us reliable information regarding the prognosis of visual functions and response to the treatment for CRAO patients at acute phase.

Efficacy of conbercept after switching from bevacizumab/ranibizumab in eyes of macular edema secondary to central retinal vein occlusion

AIM: To explore the efficacy of conbercept after switching from bevacizumab/ranibizumab in eyes of central retinal vein occlusion(CRVO) through optical coherence tomography angiography(OCTA). METHODS: Patients with prior treatment of a minimum of three consecutive intravitreal injections of either bevacizumab or ranibizumab, followed by injection of conbercept, were recruited. The minimal follow-up period after switching was 12 mo. Central retinal thickness(CRT), best-corrected visual acuity(BCVA), the interval of injections was reviewed. Perfusion density(PD) and vascular length density(VLD) of superficial and deep capillary plexus were acquired from OCTA images before and after switching. RESULTS: Twenty-four eyes were included. CRT significantly decreased from 460.71±153.23 μm(before switching) to 283.92±38.27 μm at the end of follow-up(P<0.001). However, BCVA gained to some extent(from 0.98±0.33 to 0.76±0.42 log MAR) but the difference was not significant(P=0.070). After switching to conbercept the injection interval extended from 5.2±2.3 wk to 8.3±3.9 wk(P=0.012). At the end of follow-up, PD of deep retinal layer decreased significantly compared with before switching(from 34.62%±5.27% to 33.26%±5.82%, P=0.016), similar result was found in VLD of deep retinal layer but not in PD or VLD in superficial layer.CONCLUSION: In cases of refractory macular edema secondary to CRVO, switching to conbercept improves macular thickness and extends interval of injection. Retinal microvasculature cannot improve with treatment of conbercept.

Different Dosages of Intravitreal Triamcinolone Acetonide Injections for Macular Edema Secondary to Central Retinal Vein Occlusion

Purpose:.To study the effect of intravitreal injections of triamcinolone acetonide (TA) for the treatment of macular edema secondary to central retinal vein occlusion.(CRVO).in a sample of Chinese patients from Shaanxi province. Methods:.The 50 eyes from 50 patients were separated into three TA treatment groups:.17 patients were given 4 mg/0.1 ml,.19 patients were given 8 mg/0.2 ml,.and 14 patients were given 16 mg/0.4 ml. Patients were followed up for 12 months. Foveal thickness, intraocular pressure (IOP), and best-corrected visual acuity (BCVA) were measured. Results:.Macular edema responded well both anatomically and functionally to the TA injections. After the initial intravitreal injection,.macular edema recurred at 2-4 months in the low-dose group.(4 mg),.at 3-5 months in the medium-dose group (8 mg), and at 6-9 months in the high-dose group (16 mg)..No significant difference in BCVA or in foveal thickness were observed between the first intravitreal injection and the re-injection. There was no increase in IOP after re-injection of 16 mg TA,.if the patient did not have an elevated IOP after the initial intravitreal injection of 4/8 mg TA. Conclusion: A low dosage of TA (4 mg) administered via intravitreal injection might be useful as an initial treatment for macular edema secondary to CRVO..A higher dosage of TA (16mg) can be used if there is no IOP elevation with the initial TA injection.

Central retinal artery occlusion after endovascular coil embolization for internal carotid artery aneurysm

Dear Editor,We are writing this letter to report an unexpected rare caseofcentralretinalarteryocclusion(CRAO)happened after stent-assisted coiling for internal carotid artery(ICA)aneurysm in a female patient.CRAO is a devastating ocular emergency with poor visual prognosis and no universal acceptedtreatmentatpresent.CRAOisusuallyassociated witharterialhypertension,diabetesmellitus,renaldisease.

Prevalence of SARS-CoV-2 among central retinal artery occlusion patients:A case series-HORA study report No.3

Introduction:COVID-19 patients are susceptible to hypercoagulability,thromboembolic,and vasculitis state;central retinal artery occlusion(CRAO)could be caused by hyperviscosity syndrome,thromboembolic accidents,and vasculitis.Evolving case reports are correlating CRAO with COVID-19 patients.Our case series aims to reveal the prevalence of SARS-CoV-2 among CRAO patients under the COVID-19 pandemic.Methods:Medical records of all CRAO patients who attended our tertiary referral hospital,during COVID-19 local outbreak(March to November 2020),were reviewed.Respiratory tract samples were tested for SARS-CoV-2 by the validated Xpert Xpress SARS-CoV-2 assay.If patients were able to cooperate,oropharyngeal saliva samples were obtained.Otherwise,nasopharyngeal and deep throat swabs were taken by registered nurses.Results:A total of 15 CRAO patients(7 males,8 females)were identified during the 9-month study period.The mean age was 72.1-years(range 45-88 year).None of the patients were infected by SARS-CoV-2 before their CRAO disease episodes.Three patients had a history of CRAO over the contralateral eye.No patient was diagnosed with COVID-19 up to their last follow-up(mean 255.4 days,range 152-341 days).Without any COVID-19 positive case,correlation statistical tests on SARS-CoV-2 infection and CRAO were not established.Conclusions:Some of the presumed COVID-19 related CRAO cases may be just coincident with at-risk patients,as COVID-19 is prevalent across the world.More in-depth research,with adjustment to known confounding risk factors,is needed to establish a genuine correlation.

Altered brain network centrality in patients with retinal vein occlusion: a resting-state fMRI study

AIM:To explore the intrinsic brain activity variations in retinal vein occlusion(RVO)subjects by using the voxel-wise degree centrality(DC)technique.METHODS:Twenty-one subjects with RVO and twentyone healthy controls(HCs)were enlisted and underwent the resting-state functional magnetic resonance imaging(rs-f MRI)examination.The spontaneous cerebrum activity variations were inspected using the DC technology.The receiver operating characteristic(ROC)curve was implemented to distinguish the DC values of RVOs from HCs.The relationships between DC signal of definite regions of interest and the clinical characteristics in RVO group were evaluated by Pearson’s correlation analysis.RESULTS:RVOs showed notably higher DC signals in right superior parietal lobule,middle frontal gyrus and left precuneus,but decreased DC signals in left middle temporal gyrus and bilateral anterior cingulated(BAC)when comparing with HCs.The mean DC value of RVOs in the BAC were negatively correlated with the anxiety and depression scale.CONCLUSION:RVO is associated aberrant intrinsic brain activity patterns in several brain areas including painrelated as well as visual-related regions,which might assist to reveal the latent neural mechanisms.