Relationship between syndrome elements and anterior communicating artery opening in patients with smptomatic severe carotid artery stenosis/occlusion

Objective To study the relationship between syndrome elements and anterior communicating artery(ACoA)opening in patients with symptomatic severe carotid artery stenosis/occlusion.Methods Thirty-six patients with symptomatic severe carotid stenosis/occlusion were collected,including 26 patients with cerebral infarction and 10 patients with transient ischemic attack(TIA).Syndrome elements at five time points were collected.Computer tomography angiography(CTA)combined with magenic resonance angiograp(MRA)was used to evaluate the primary collateral circulation,and the prognosis and syndrome elements were statistically analyzed according to whether the ACoA was open or not.Results The ACoA was open more in the primary collateral circulation among patients with symptomatic severe carotid stenosis/occlusion.There was a statistically significant difference in national institute of health stroke scale(NIHSS)score improvement and good prognosis[the modified rankin scale(mRS)≤2]between the ACoA open group and the ACoA nonopen group on the 90th day(P<0.05).The proportion of patients with internal wind syndrome,blood stasis syndrome,Qi deficiency syndrome,and Yin deficiency syndrome in the ACoA non-open group was higher than that in the open group.Conclusion In the patients with severe carotid artery stenosis/occlusion,the group with presence of anterior communicating artery had better prognosis.The syndrome elements are more complex in the group without the presence of anterior communicating artery.The proportion of Qi deficiency syndrome was positively correlated with the non-opening of anterior communicating artery.The imaging evaluation of collateral circulation can provide guidance for syndrome differentiation and treatment.

Mimicking aneurysm in a patient with chronic occlusion of the left middle cerebral artery:A case report

BACKGROUND With the popularization of various cerebrovascular imaging methods and increased attention to the field,more cerebrovascular diseases are being detected in asymptomatic patients.Different cerebrovascular diseases are typically isolated but occasionally occur simultaneously,causing difficulties in diagnosis and treatment.Morphological changes in the collateral circulation of blood vessels in chronic cerebral artery occlusion patients are slow and dynamic,intercepting morphological development at a specific moment.Excessive reliance on single imaging tests such as digital subtraction cerebral angiography(DSA)can lead to misdiagnosis.CASE SUMMARY We report a 52-year-old male who was admitted to our department for treatment of an unruptured aneurysm during a follow-up examination for brain trauma after 1 mo.Computed tomography(CT)scan was negative,but CT angiography(CTA)revealed a sac-like bulge at the bifurcation of the left middle cerebral artery.DSA revealed an unruptured aneurysm with unique scapular morphology.The stump of a middle cerebral artery occlusion was observed during exposure during aneurysm clipping surgery,and the diagnosis of chronic cerebral artery occlusion was confirmed intraoperatively.This case was confusing because of the peculiar morphology of the arterial stump and compensatory angiogenesis due to multiple cerebral artery stenoses observed on preoperative CTA and DSA.The surgery did not cause secondary damage to the patient,and medical treatment for risk factors was continued postoperatively.CONCLUSION Multiple cerebral arterial stenoses can occur in conjunction with aneurysms or arteriovenous malformations,and their unique morphology can lead to misdiagnosis.

Intelligent diagnosis of retinal vein occlusion based on color fundus photographs

AIM:To develop an artificial intelligence(AI)diagnosis model based on deep learning(DL)algorithm to diagnose different types of retinal vein occlusion(RVO)by recognizing color fundus photographs(CFPs).METHODS:Totally 914 CFPs of healthy people and patients with RVO were collected as experimental data sets,and used to train,verify and test the diagnostic model of RVO.All the images were divided into four categories[normal,central retinal vein occlusion(CRVO),branch retinal vein occlusion(BRVO),and macular retinal vein occlusion(MRVO)]by three fundus disease experts.Swin Transformer was used to build the RVO diagnosis model,and different types of RVO diagnosis experiments were conducted.The model’s performance was compared to that of the experts.RESULTS:The accuracy of the model in the diagnosis of normal,CRVO,BRVO,and MRVO reached 1.000,0.978,0.957,and 0.978;the specificity reached 1.000,0.986,0.982,and 0.976;the sensitivity reached 1.000,0.955,0.917,and 1.000;the F1-Sore reached 1.000,0.9550.943,and 0.887 respectively.In addition,the area under curve of normal,CRVO,BRVO,and MRVO diagnosed by the diagnostic model were 1.000,0.900,0.959 and 0.970,respectively.The diagnostic results were highly consistent with those of fundus disease experts,and the diagnostic performance was superior.CONCLUSION:The diagnostic model developed in this study can well diagnose different types of RVO,effectively relieve the work pressure of clinicians,and provide help for the follow-up clinical diagnosis and treatment of RVO patients.

Novel approach of ultrasound-guided lateral recess block for a patient with lateral recess stenosis: A case report

BACKGROUND Ultrasound guide technology,which can provide real-time visualization of the needle tip and tissues and avoid many adverse events,is widely used in mini-mally invasive therapy.However,the studies on ultrasound-guided Lateral recess block(LRB)are limited,this is probably because there is no recognized standard method for ultrasound scanning.This study aimed to evaluate the effect of ultrasound-guided LRB in patients with lateral recess stenosis(LRS).CASE SUMMARY A 65-year-old patient complained of low back pain accompanied occasionally by pain and numbness in the left lower limb.Physical examination showed ten-derness on the spinous process and paraspinal muscles from L1 to S1,extensor hallucis longus and tibialis anterior weakness(muscle strength:4-),and a positive straight leg raising test in the left lower limb(60°).Magnetic resonance imaging showed L4–L5 disc degeneration with left LRS and nerve root entrapment.Subsequently,the patient was diagnosed with LRS.This patient was treated with a novel ultrasound-guided LRB approach.The patient’s symptoms significantly improved without any complications at 1 wk postoperatively and at the 3-month follow-up.CONCLUSION This is the first report on the LRS treatment with ultrasound-guided LRB from the contralateral spinous process along the inner side of the articular process by out-plane technique.Further studies are expected to investigate the efficacy and safety of ultrasound-guided LRB for patients with LRS.

Imaging characteristics and treatment strategies for carotid artery occlusion caused by skull base fracture:Three case reports

BACKGROUND Traumatic internal carotid artery(ICA)occlusion is a rare complication of skull base fractures,characterized by high mortality and disability rates,and poor prognosis.Therefore,timely discovery and correct management are crucial for saving the lives of such patients and improving their prognosis.This article retrospectively analyzed the imaging and clinical data of three patients,to explore the imaging characteristics and treatment strategies for carotid artery occlusion,combined with severe skull base fractures.CASE SUMMARY This case included three patients,all male,aged 21,63,and 16 years.They underwent plain film skull computed tomography(CT)examination at the onset of their illnesses,which revealed fractures at the bases of their skulls.Ultimately,these cases were definitively diagnosed through CT angiography(CTA)examinations.The first patient did not receive surgical treatment,only anticoagulation therapy,and recovered smoothly with no residual limb dysfunction(Case 1).The other two patients both developed intracranial hypertension and underwent decompressive craniectomy.One of these patients had high intracranial pressure and significant brain swelling postoperatively,leading the family to choose to take him home(Case 2).The other patient also underwent decompressive craniectomy and recovered well postoperatively with only mild limb motor dysfunction(Case 3).We retrieved literature from PubMed on skull base fractures causing ICA occlusion to determine the imaging characteristics and treatment strategies for this type of disease.CONCLUSION For patients with cranial trauma combined with skull base fractures,it is essential to complete a CTA examination as soon as possible,to screen for blunt cerebrovascular injury.

Mimicking aneurysm in a patient with chronic occlusion of the left middle cerebral artery

The chronic occlusion of intracranial arteries generally has no or mild clinical symptoms,and the clinical symptoms of acute cerebral artery occlusion are mostly manifested as severe cerebral infarction symptoms,which often make early diagnosis difficult,thus losing the best treatment opportunity.Once cerebral infarction occurs,the consequences are difficult to recover.This is also an important reason for the high misdiagnosis rate and mortality of this disease.In this paper,the characteristics of the disease were analyzed to provide clinical reference.

Total suprarenal aortic occlusion with cardiac disease: a case series of three cases

Acute aortic occlusion(AAO)has been very rarely reported in the literature and is a potentially life-threatening emergency.[1-5]AAO mostly occurs in cardiac disease patients,[1-4,6,7]and leads to cardiac complications.[1,2,5,6]Suprarenal aortic occlusion(SAO)is a very rare type of AAO,and infrarenal aortic occlusion(IAO)accounts for 75.8%-97.8%.[1,3,5-7]SAO is different from IAO in some clinical manifestations,treatment strategies,and prognoses.[3,6-8]SAO with cardiac disease will make the condition more complex and could easily cause a delay in diagnosis and portend worse outcomes with amputation and mortality rates.[1,3,6]Early and fast diagnosis and positive revascularization treatment are necessary to prevent cases from becoming fatal.[1-3]Herein,we present a case series of SAO with cardiac disease.

Diagnostic performance of intravascular ultrasound-based fractional flow reserve in evaluating of intermediate left main stenosis

BACKGROUND The recently introduced ultrasonic flow ratio(UFR),is a novel fast computational method to derive fractional flow reserve(FFR)from intravascular ultrasound(IVUS)images.In the present study,we evaluate the diagnostic performance of UFR in patients with intermediate left main(LM)stenosis.METHODS This is a prospective,single center study enrolling consecutive patients with presence of intermediated LM lesions(diameter stenosis of 30%-80%by visual estimation)underwent IVUS and FFR measurement.An independent core laboratory assessed offline UFR and IVUS-derived minimal lumen area(MLA)in a blinded fashion.RESULTS Both UFR and FFR were successfully achieved in 41 LM patients(mean age,62.0±9.9 years,46.3%diabetes).An acceptable correlation between UFR and FFR was identified(r=0.688,P<0.0001),with an absolute numerical difference of 0.03(standard difference:0.01).The area under the curve(AUC)in diagnosis of physiologically significant coronary stenosis for UFR was 0.94(95%CI:0.87-1.01),which was significantly higher than angiographic identified stenosis>50%(AUC=0.66,P<0.001)and numerically higher than IVUS-derived MLA(AUC=0.82;P=0.09).Patient level diagnostic accuracy,sensitivity and specificity for UFR to identify FFR≤0.80 was 82.9%(95%CI:70.2-95.7),93.1%(95%CI:82.2-100.0),58.3%(95%CI:26.3-90.4),respectively.CONCLUSION In patients with intermediate LM diseases,UFR was proved to be associated with acceptable correlation and high accuracy with pressure wire-based FFR as standard reference.The present study supports the use of UFR for functional evaluation of intermediate LM stenosis.

The prognostic value of collateral circulation in coronary chronic total occlusion underwent percutaneous coronary intervention

BACKGROUND The prognostic value of coronary collateral circulation(CC)in patients undergoing chronic total occlusion(CTO)percutaneous coronary intervention(PCI)is underdetermined.The purpose of the study was to assess the prognostic value of current two CC grading systems and their association with long-term outcomes in patients with CTO underwent PCI.METHODS We consecutively enrolled patients with single-vessel CTO underwent PCI between January 2010 and December2013.All patients were categorized into well-developed or poor-developed collaterals group according to angiographic Werner's CC(grade 2 vs.grade 0–1)or Rentrop(grade 3 vs.grade 0–2)grading system.The primary endpoint was 5-year cardiac death.RESULTS Of 2452 enrolled patients,the overall technical success rate was 74.1%.Well-developed collaterals were present in686 patients(28.0%)defined by Werner's CC grade 2,and in 1145 patients(46.7%)by Rentrop grade 3.According to Werner's CC grading system,patients with well-developed collaterals had a lower rate of 5-year cardiac death compared with those with poordeveloped collaterals(1.6%vs.3.3%,P=0.02),those with suboptimal recanalization was associated with higher rate of 5-year cardiac death compared with optimal recanalization(4.7%vs.0.8%,P=0.01)and failure patients(4.7%vs.1.6%,P=0.12).However,the similar effect was not shown in Rentrop grading system.CONCLUSIONS In patients with the single-vessel CTO underwent PCI,well-developed collaterals by Werner's CC definition were associated with lower rate of 5-year cardiac death.Werner's CC grading system had a greater prognostic value than Rentrop grading system in patients with CTO underwent PCI.

Accurate diagnosis of severe coronary stenosis based on resting magnetocardiography: a prospective, single-center, cross-sectional analysis

OBJECTIVE To evalu ate the role of resting magnetocardiography in identifying seve re coronary artery stenosis in patients with suspected coronary artery disease.METHODS A total of 513 patients with angina symptoms were included and divided into two groups based on the extent of coronary artery disease determined by angiography:the non-severe coronary stenusis group(<70% stenosis) and the severe coronary stenosis group(≥70% stenosis).The diagnostic model was constructed using magnetic field map(MFM) parameters,either individually or in combination with clinical indicators.The performance of the models was evaluated using receiver operating characteristic curves,accuracy,sensitivity,specificity,positive predictive value(PPV) and ne gative predictive value(NPV).Calibration plots and decision curve analysis were performed to investigate the clinical utility and performance of the models,respectively.RESULTS In the severe coronary stenosis group,QR_MCTDd,S_MDp,and TT_(MA)C_(50) were significantly higher than those in the non-severe coronary stenosis group(10,46±10.66 vs,5.11±6.07,P <0.001;7.2±8.64 vs.4.68±6.95,P=0.003;0.32±57.29 vs.0.26±57.29,P <0.001).While,QR_MV_(amp),R_(MA),and T_(MA) in the severe coronary stenosis group were lower(0.23±0.16 vs.0.28±0.16,P<0.001;55.06±48.68 vs.59.24±53.01,P<0.001;51.67±39.32 vs. 60.45±51.33,P <0.001).Seven MFM parameters were integrated into the model,resulting in an area under the curve of 0.810(95% CI:0.765-0.855).The sensitivity,specificity,PPV,NPV,and accurecy were 71.7%,80.4%,93.3%,42.8 %,and 73.5%;respectevely.The combined model exhibited an area under the curve of 0.845(95% CI:0.798-0.892).The sensitivity,specificity,PPV,NPV,and accuracy were 84.3%,73.8%,92.6%,54.6%,and 82.1%;respectively.Calibration curves demonstrate d excellent agreement between the nomogram prediction and actual observation.The decision curve analysis showed that the c ombine d model provided greater net benefit compared to the magnetocardingraphy model.CONCLUSIONS The novel quantitative MFM parameters,whether used individually or in combination with clinical indicators,have been shown to effectively pre dict the risk of severe coronary stenosis in patients presenting with angina-like symptoms.Magnetocardiography,an emerging non-invasive diagnostic tool,warrants further exploration for its potential in diagnosing coronary heart disease.

Causal effect of psoriasis on aortic valve stenosis:a two-sample Mendelian randomization study

Background Epidemiological studies have suggested a potential connection between psoriasis and an increased risk of aortic valve stenosis(AS),though the impact of psoriasis on AS progression remains uncertain.The study aims to investigate the causal relationship between psoriasis and AS using Mendelian randomization(MR)analysis,as well as to uncover potential mechanisms underlying this association.Methods A two-sample MR analysis was conducted using publicly available summary statistics from genome-wide association studies(GWAS)of psoriasis and AS.Cis-eQTL and significant genes were identified for each causal single-nucleotide polymorphisms(SNPs),followed by pathway enrichment and protein-protein interaction(PPI)analysis for functional evaluation.Hub genes were pinpointed by Cytospace.The transcriptional profile of AS population was acquired,and interconnected genes networks were clustered using Molecular Complex Detection(MCODE).Results Our results demonstrate a significant causal relationship between psoriasis and AS,with a genetic predisposition to psoriasis associated with a higher AS risk(odds ratio:1.46).Pathway and PPI analyses unveiled 15 hub genes,including HLA-C,HLA-B,ISG15,IFIT3,and MX2,along with immune-related pathways linking psoriasis and AS.Moreover,the transcriptional profiling of the AS database highlighted the significant involvement of adaptive immune cells in AS development.Notably,among the 15 hub genes,ISG15,MX2,OAS3,OASL,IFI6,and EPSTI1 exhibited higher expression in the AS population.Conclusion Our study provides compelling evidence supporting a causal relationship between psoriasis and AS.Furthermore,the identified hub genes and immune-related pathways may play an important role in the development of both diseases.

Significance of balloon aortic valvuloplasty as palliative procedure for symptom benefit in patients with severe aortic stenosis

Aortic stenosis(AS)stands out as the most prevalent individual valvular defect globally.The onset and progression of AS mirror an active process akin to atherosclerosis,and the traditional triad of symptoms includes chest pain,breathlessness,and loss of consciousness.Prognosis takes a significant downturn when symptoms manifest,with mortality reaching approximately 50%-85% within the subsequent 5 years after symptom onset.

Predictive value of neutrophil-to-lymphocyte ratio in coronary chronic total occlusion patients

BACKGROUND The neutrophil to lymphocyte ratio(NLR)has been reported as a novel predictor for atherosclerosis and car-diovascular outcomes.This study aimed to determine the effects of NLR on long-term clinical outcomes of chronic total occlusion(CTO)patients.METHODS A total of 670 patients with CTO who met the inclusion criteria were included at the end of the follow-up period.Patients were divided into tertiles according to their baseline NLR levels at admission:low(n=223),intermediate(n=223),and high(n=224).The incidence of major adverse cardiac events(MACEs)during the follow-up period,including all-cause death,nonfatal myocardial infarction(MI),or ischemia-driven revascularization,were compared among the three groups.RESULTS Major adverse cardiac events were observed in 27 patients(12.1%)in the low tertile,40(17.9%)in the intermediate tertile,and 61(27.2%)in the high NLR tertile(P<0.001).Kaplan-Meier analysis demonstrated a significantly higher incidence of MACE,ischemia-driven coronary revascularization,non-fatal MI,and mortality in patients within the high tertile than those in the low and intermediate groups(all P<0.001).Multivariable COX regression analysis showed that the high tertile of baseline NLR level showed a strong association with the risk of MACE(hazard ratio[HR]=2.21;95%confidence interval[CI]:1.21-4.03;P=0.009),ischemia-driven coronary revascularization(HR=3.19;95%CI:1.56-6.52;P=0.001),MI(HR=2.61;95%CI:1.35-5.03;P=0.043)and mortality(HR=3.78;95%CI:1.65-8.77;P=0.001).CONCLUSION Our findings suggest that NLR is an inexpensive and readily available biomarker that can independently pre-dict cardiovascular risk in patients with CTO.

Unilateral branch retinal artery occlusion in association with COVID-19:a case report

Dear Editor,I am Kunihiko Hirosawa of the Department of Ophthalmology at Juntendo University Hospital.I am writing to present a case of concomitant Coronavirus Disease 2019(COVID-19)with branch retinal artery occlusion(BRAO).BRAO presents as a sudden,painless loss of vision on the afflicted side and is most often focal in nature[1].

Retinal vein occlusion coinciding with paracentral acute middle maculopathy in patient with menorrhagia causing life-threatening anemia

Dear Editor,We present two cases of retinal vein occlusion,one central retinal vein occlusion(CRVO)and one branch retinal vein occlusion(BRVO)respectively,coinciding with paracentral acute middle maculopathy(PAMM)on optical coherence tomography(OCT)in patients with menorrhagia causing life-threatening anemia.PAMM is considered a manifestation of acute ischemia affecting the deep macular capillary plexus.

Recanalization of anastomotic occlusion following rectal cancer surgery using a rendezvous endoscopic technique with transillumination:A case report

BACKGROUND Colorectal anastomotic occlusion is a serious complication of colorectal cancer surgery.Although several treatment strategies have been proposed,the mana-gement of anastomotic occlusion remains challenging.In this report,we present a case of anastomotic occlusion recanalization performed using a novel technique involving two endoscopes,one for radial incision and the other serving as a guide light.This novel technique offers significant advantages in terms of operational feasibility,reduced invasiveness,rapid recovery,and shortened hospital stay.CASE SUMMARY A 37-year-old man underwent low anterior resection and prophylactic double-lumen ileostomy for rectal cancer in June,2023.Two months later,complete anastomotic occlusion was observed on colonoscopy.Therefore,we developed a novel atresia recanalization technique.Two endoscopes were placed,one through the colonic anastomosis and the other through the anus.A radial incision was successfully made from the colonic side,guided by the light of the endoscope from the anal side.Atresia recanal-ization was performed within 20 minutes.Three weeks after recanalization,colonoscopy revealed that the diameter of the colorectal anastomosis was approximately 16 mm and the patient therefore underwent stoma reversal in September.During the follow-up period of approximately one year,the patient remained well and no stenosis or obstruction symptoms were observed.CONCLUSION Endoscopic atresia recanalization of colorectal anastomotic occlusion assisted by an opposing light source is safe and effective.

0D-1D coupling model and 3D fluid-structure interaction model based on coronary CT angiography for displaying hemodynamic characteristics of coronary artery stenosis

Objective To observe value of 0D-1D coupling model and 3D fluid-structure interaction(FSI)model based on coronary CT angiography(CCTA)for displaying hemodynamic characteristics of coronary artery stenosis.Methods Based on CCTA data of the stenosed left anterior descending branch(LAD)in a patient with coronary heart disease,an 0D-1D coupling model and 3D FSI model were built,respectively.Then hemodynamic characteristic indexes,including the pressure,flow velocity and wall shear stress(WSS)were obtained in every 0.01 s during 1 s at 5 sampling points(i.e.sampling point 1—5)using these 2 models,respectively,and the consistencies of the results between models were evaluated with Spearman correlation coefficient r s.Results The time consuming for construction of 0D-1D coupling model and 3D FSI model was 0.033 min and 704 min,respectively.Both models showed basically distribution of the pressure,flow velocity and WSS of the stenosed LAD.For more details,the pressure at the stenosed segment of LAD and the proximal segment of stenosis were both higher,which gradually decreased at the distal segment of stenosis,and the flow velocity at the proximal segment of stenosis was in a relatively slow and uniform condition,with significantly increased flow velocity and WSS at the stenosed segment.Compared with 3D FSI model,0D-1D vascular coupling model was relatively unrefined and lack of distal flow lines when displaying blood flow velocity.For sampling point 2 at the stenosed segment of LAD,no significant consistency for pressure between 2 models was found(P=0.118),but strong consistency for the flow velocity and WSS(r s=0.730,0.807,both P<0.05).The consistencies of pressure,flow velocity and WSS between 2 models at the proximal and distal segment of stenosis,i.e.1,3—5 sampling points were week to moderate(r s=0.237—0.669,all P<0.05).Conclusion 0D-1D coupling model exhibited outstanding computational efficiency and might provide relatively reasonable results,while 3D FSI model showed higher accuracy for details and streamline when simulating LAD stenosis.

A novel mouse model of calcific aortic valve stenosis

Background:Calcific aortic valve stenosis(CAVS)is one of the most challenging heart diseases in clinical with rapidly increasing prevalence.However,study of the mecha-nism and treatment of CAVS is hampered by the lack of suitable,robust and efficient models that develop hemodynamically significant stenosis and typical calcium deposi-tion.Here,we aim to establish a mouse model to mimic the development and features of CAVS.Methods:The model was established via aortic valve wire injury(AVWI)combined with vitamin D subcutaneous injected in wild type C57/BL6 mice.Serial transthoracic echocardiography was applied to evaluate aortic jet peak velocity and mean gradi-ent.Histopathological specimens were collected and examined in respect of valve thickening,calcium deposition,collagen accumulation,osteogenic differentiation and inflammation.Results:Serial transthoracic echocardiography revealed that aortic jet peak velocity and mean gradient increased from 7 days post model establishment in a time depend-ent manner and tended to be stable at 28 days.Compared with the sham group,sim-ple AVWI or the vitamin D group,the hybrid model group showed typical pathological features of CAVS,including hemodynamic alterations,increased aortic valve thicken-ing,calcium deposition,collagen accumulation at 28 days.In addition,osteogenic dif-ferentiation,fibrosis and inflammation,which play critical roles in the development of CAVS,were observed in the hybrid model.Conclusions:We established a novel mouse model of CAVS that could be induced efficiently,robustly and economically,and without genetic intervention.It provides a fast track to explore the underlying mechanisms of CAVS and to identify more effec-tive pharmacological targets.

Morphological and functional observations of a novel model of retinal ischemia injury induced by bilateral carotid artery stenosis in mice

AIM:To investigate the features of retinal ischemic injuries in a novel mouse model with bilateral carotid artery stenosis(BCAS).METHODS:BCAS was induced with microcoil implantation in 6-8-week-old C57BL6 mice.Cerebral blood flow was monitored at 2,7,and 28d postoperatively.Retinal morphological changes were evaluated by fundus photography and hematoxylin-eosin staining.Fluorescein fundus angiography(FFA)was performed to detect retinal vascular changes and circulation.The levels of apoptosis,activation of neurogliosis,and expression of hypoxiainducible factor(HIF)-1αin the retina were assessed by Western blotting and immunofluorescence staining,followed by retinal ganglion cell(RGC)density detection.Additionally,electrophysiological examinations including photopic negative response(PhNR)was also performed.RESULTS:The mice demonstrated an initial rapid decrease in cerebral blood flow,followed by a 4-week recovery period after BCAS.The ratio of retinal artery and vein was decreased under fundus photography and FFA.Compared with the sham mice,BCAS mice showed thinner retinal thickness on day 28.Additionally,apoptosis was increased and RGC density was decreased mainly in peripheral retinal region.Neurogliosis was mainly located in the inner retinal layers,with a stable increase in HIF-1αexpression.The dark-adapted electroretinogram showed a notable reduction in the a-,b-,and oscillatory potential(OP)wave amplitudes between days 2 and 7;this gradually recovered over the following 4wk.However,the b-and OPwave amplitudes were still significantly decreased on PhNR examination on day 28.CONCLUSION:BCAS can result in relatively mild retinal ischemia injuries in mice,mainly in the inner layer and peripheral region.Our study provides a novel animal model for investigating retinal ischemic diseases.

Dexamethasone implant for refractory macular edema secondary to diabetic retinopathy and retinal vein occlusion

AIM:To evaluate the efficacy,timing of retreatment and safety of dexamethasone(DEX)implant on macular edema(ME)secondary to diabetic retinopathy(DME)and retinal vein occlusion(RVO-ME)patients who were refractory to anti-vascular endothelial growth factor(VEGF)treatment.METHODS:This retrospective study included 37 eyes received at least one DEX implant treatment for DME or RVO-ME between January 1,2019,and January 1,2023.These refractory DME and RVO-ME cases received at least 5 anti-VEGF injections and failure to gain more than 5 letters or a significant reduction in central retinal thickness(CRT).The best corrected visual acuity(BCVA)and CRT were measured at baseline,and at 1,3,4 and 6mo post-DEX implant injection.Adverse events such as elevated intraocular pressure(IOP)and cataract were recorded.RESULTS:For RVO cases(n=22),there was a significant increase in BCVA from 0.27±0.19 to 0.35±0.20 at 6mo post-DEX injection(P<0.05)and CRT decreased from 472.1±90.6 to 240.5±39.0μm at 6mo(P<0.0001).DME cases(n=15)experienced an improvement in BCVA from 0.26±0.15 to 0.43±0.20 at 6mo post-DEX implant injection(P=0.0098),with CRT reducing from 445.7±55.7 to 271.7±34.1μm at 6mo(P<0.0001).Elevated IOP occurred in 45.9% of patients but was well-controlled with topical medications.No cases of cataract or other adverse events were reported.CONCLUSION:DEX implants effectively improve BCVA and reduce CRT in refractory DME and RVO-ME.Further research with larger cohorts and longer follow-up periods is needed to confirm these findings and assess long-term outcomes.