Visual outcomes after carotid reconstructive surgery for ocular ischemia

Ocular Ischemic Syndrome and the Role of Carotid Artery Revascularization

BACKGROUND

Ocular ischemic syndrome (OIS) is a rare presentation of atherosclerotic carotid artery stenosis that can result in permanent visual loss. This severely disabling syndrome remains under diagnosed and undertreated due to lack of awareness; especially since it requires expedited multidisciplinary care. The relevance of early diagnosis and treatment is increasing due to an increasing prevalence of cerebrovascular disease.

METHODS

The long-term visual and cerebrovascular outcomes following intervention for nonarteritic OIS, remain poorly described and were the objective of this concise review. We conducted a PubMed search to include all English language publications (cohort studies and case reports) between 2002 and 2023.

RESULTS

A total of 33 studies (479 patients) report the outcomes of treatment of OIS with carotid endarterectomy (CEA, 304 patients, 19 studies), and carotid artery stenting (CAS, 175 patients, 14 studies). Visual outcomes were improved or did not worsen in 447 patients (93.3%). No periprocedural stroke was reported. Worsening visual symptoms were rare (35 patients, 7.3%); they occurred in the immediate postoperative period secondary to ocular hypoperfusion (3 patients) and in the late postoperative period due to progression of systemic atherosclerotic disease. Symptomatic recurrence due to recurrent stenosis after CEA was reported in 1 patient (0.21%); this was managed successfully with CAS. None of these studies report the results of transcarotid artery revascularization, the long-term operative outcome or stroke rate.

CONCLUSIONS

OIS remains to be an underdiagnosed condition. Early diagnosis and prompt treatment are crucial in reversal or stabilization of OIS symptoms. An expedited multidisciplinary approach between vascular surgery and ophthalmology services is necessary to facilitate timely treatment and optimize outcome. If diagnosed early, both CEA and CAS have been associated with visual improvement and prevention of progressive visual loss.

Is a Carotid Doppler Scan Useful for Managing Patients with Suspected Ocular Ischemic Syndrome?

Purpose

This review aims to understand the value of a carotid Doppler scan (CDS) when managing patients with clinical/suspected ocular ischaemic syndrome (OIS); correlations between internal carotid artery (ICA) stenosis reports; subsequent patterns of referral to vascular experts; and subsequent decisions concerning surgical versus medical management.

Methods

A retrospective review of 402 CDS requests by a single eye center over 4 years (2016-2019) for patients with a clinical suspicion of OIS was conducted. Data analysis included 344 patients who had reported CDS of both ICAs. We also studied referral patterns by ophthalmologists to other specialties.

Results

CDS requests were related to the retina (53.2%), neuro/TIA problems (31.1%), glaucoma (10.5%) and other issues (5.2%). The majority of patients (209/344, 60.8%) had normal CDA results. Of the 688 ICAs reported, 469 (68.2%) were normal, 219 (31.8%) had atheroma present, and only 83 (12.1%) had significant stenosis. Of 83 ICAs with stenosis, 23 (27.7%) had ≥70% stenosis, 24 (28.9%) had 50-69% stenosis, and 25 (30.1%) had <50% stenosis. A total of 60/344 (17.4%) patients were referred to vascular/stroke teams: 15/60 (25%) referred had bilateral disease, and only 2/60 (3.3%) were offered carotid endarterectomy. All referred patients commenced statins and low-dose aspirin.

Conclusion

Our cohort showed a low incidence of ICA stenosis according to CDS reports in patients with suspected OIS. There were very low rates of vascular and endarterectomy referral. Commencement of conservative treatment (mini aspirin+statin) by ophthalmologists could be beneficial even in the early stage of presenting clinical evidence of OIS.

Ocular signs of carotid stenosis in ipsi- and contralateral eyes before and after carotid endarterectomy: a prospective study

PURPOSE

We describe hypoperfusion-related and embolic ocular signs of carotid stenosis (CS) before and six months after carotid endarterectomy (CEA) in a CS population.

METHODS

We enrolled prospectively 70 CEA patients (81% male, mean age 69) and 41 non-medicated control subjects (76%, 68), from March 2015 to December 2018, assessing intraocular pressure (IOP), best-corrected visual acuity (BCVA) in logMAR units and performing a bio-microscopy examination.

RESULTS

Main index symptoms included amaurosis fugax (Afx) (29, 41%) and hemispheric TIA (17, 24%), and 17 (24%) were asymptomatic. Of the 70, 17 patients (24%, 95% CI 16-36) showed ocular signs of CS. Of four embolic (Hollenhorst plaques) findings, one small macular plaque disappeared postoperatively. Four had hypoperfusion, that is ocular ischaemic syndrome (OIS), requiring panretinal photocoagulation: one for multiple mid-peripheral haemorrhages, two for iris neovascularization and one for neovascular glaucoma (NVG); only the NVG proved irreversible. Nine (de novo in three) showed mild OIS, that is only few mid-peripheral haemorrhages, ranging pre- /postoperatively in ipsilateral eyes from one to eleven (median two)/ one to two (median one), and in contralateral eyes from three to nine (median five)/ one to six (median three). Pre- and postoperative median BCVA was 0 or better, and mean IOP was normal, except in the NVG patient. Temporary visual impairment from 0 to 0.3 occurred in one eye soon after CEA due to ocular hyperperfusion causing macular oedema.

CONCLUSIONS

Ocular signs of CS are common in CEA patients, ranging from few mid-peripheral haemorrhages to irreversible NVG. Clinicians should be aware of these signs in detecting CS.

Therapeutic Management of Ocular Ischemia in Takayasu's Arteritis: A Case-Based Systematic Review

Background

Takayasu’s arteritis (TA) is a rare, chronic granulomatous large-vessel vasculitis that can lead to ocular ischemia. Ocular outcomes after therapeutic management in TA remain largely unknown. We herein conduct a case-based systematic review to address the current treatment options in this particular cohort.

Methods

PubMed, Medline, and EMBASE databases were searched pertaining to ocular outcomes after systemic treatment in TA. Studies reporting ocular examinations before and after treatment in TA patients with ocular ischemia were included. Clinical characteristics, therapies, ocular outcomes, and complications were recorded.

Results

A 29-year-old woman with newly diagnosed TA showed dramatic regression of Takayasu’s retinopathy (TR) following balloon angioplasty. Optical coherence tomography angiography (OCTA) was used as a novel strategy for subsequent follow-up. A total of 117 eyes of 66 patients with a median age of 27 years were included for systematic review. TR was the most common ocular manifestation. Oral steroids were prescribed in nearly all patients (n = 65), followed by the use of methotrexate and antiplatelet therapy. Of the patients, 65.8% and 34.2% underwent open surgery and endovascular procedure, respectively. The median follow-up period was 12 weeks (interquartile range 8–33.5). Surgical therapy showed better ocular improvement (including visual and imaging responses) in both acute and chronic vision loss, along with fewer complications than medical therapy alone. In the surgical group, the visual prognosis was significantly better in patients with initial visual acuity better than 20/200 (p = 0.03) and those who underwent surgery before stage III TR (p = 0.01). Ocular outcomes were equivalent in the two surgical approaches.

Conclusion

Clinicians should be familiar with ophthalmic manifestations of this potentially treatable complication in TA. Compared with medical therapy alone, surgical intervention might be a better choice for both acute and chronic vision loss. Surgery is best recommended before the onset of irreversible ischemia to the globe. A combined regimen (oral steroids, immunosuppressants, and antiplatelet drugs) might be effective for those with surgical contradictions or reluctance to an invasive procedure. Physicians should be aware of the importance of ocular examinations, including OCTA, during the diagnosis and follow-up in TA.

[Ocular microcirculation after revascularization of the internal carotid artery in the early postoperative period]

Carotid artery stenosis is the most common cause of ischemic stroke and transient ischemic attacks in the population of developed countries. Carotid endarterectomy (CEA) and carotid stenting (CAS) are effective treatments for carotid stenosis. In view of the need to improve the diagnosis of this condition and the anatomical relationship of the internal carotid arteries and vessels of the eye, studying retinal microvasculature has become an urgent problem. The theory suggesting that changes in ocular blood flow parameters may reflect disease status in patients with internal carotid artery (ICA) stenosis requires further investigation.

PURPOSE

To study the impact of CEA and CAS interventions on ocular blood flow in patients with clinically significant ICA stenosis in the early postoperative period.

MATERIAL AND METHODS

Thirty-two patients with hemodynamically significant stenosis (≥75%) of the left or right ICA were examined using optical coherence tomography angiography (OCT-A) and flowmetry before and after CEA or CAS in order to assess the changes in ocular blood flow parameters.

RESULTS

There were no significant differences in hemodynamic parameters in the eyes on the side of the stenotic and non-stenotic ICA before revascularization. In the early postoperative period (3-7 days) in the ipsilateral eyes, there was an increase in blood flow density and vascular density at the level of the superficial and deep plexuses in the macular area (p≤0.05), as well as an increase in the ocular blood flow volume, the level of tolerated intraocular pressure (p≤0.05) and a decrease in intraocular pressure (p≤0.05) bilaterally. In the contralateral eyes, after ICA revascularization there was a partial improvement in microcirculation parameters according to OCT-A (p≤0.05). Peripapillary blood flow density and peripapillary vessel density did not change significantly either on the ipsilateral or the contralateral side.

CONCLUSION

In patients with clinically significant ICA stenosis, ICA revascularization by stenting or endarterectomy contributed to an improvement in retinal microcirculation and retrobulbar blood flow in both eyes. OCT-A and flowmetry allow non-invasive assessment of retinal microvessels and retrobulbar blood flow, and the measurements provided by these methods can serve as valuable biomarkers for predicting and monitoring hemodynamic changes in patients who undergo CEA and CAS surgeries.

Carotid endarterectomy restores decreased vision due to chronic ocular ischemia

BACKGROUND

The therapeutic effect of carotid endarterectomy (CEA) on visual disturbance caused by chronic ocular ischemia due to carotid artery stenosis has not been validated. This prospective observational study aims to investigate whether CEA is associated with an increase in ocular blood flow (OBF) and postoperative visual improvement.

METHODS

In total, 41 patients with carotid artery stenosis treated by CEA between March 2015 and September 2018 were enrolled in this study. OBF was evaluated by laser speckle flowgraphy, which can measure the mean blur ratio (MBR) which is well correlated to the absolute retinal blood flow. Visual acuity was assessed before and after CEA by subjective improvement and objective visual assessment using CSV-1000, an instrument used to test contrast sensitivity.

RESULTS

OBF increased after CEA on the operated side (mean MBR 33.5 vs 38.2, p < 0.001) but not on the non-operated side (mean MBR 37.8 vs 37.5, p = 0.50). After CEA, 23 patients (56.1%) reported subjective visual improvement on the operated side. The mean CSV-1000 score among the patients with increased OBF after CEA (5.44 vs 5.88, p = 0.04) but not among those without increased OBF (5.48 vs 5.95, p = 0.09). The mean CSV-1000 scores increased significantly after CEA in 18 patients with decreased vision and decreased OBF (4.51 vs 5.37, p < 0.001), but not in the 23 patients without those (6.19 vs 6.31, p = 0.6).

CONCLUSION

CEA may successfully reverse visual dysfunction caused by chronic ocular ischemia due to carotid artery stenosis by increasing OBF.

Relationship between ophthalmic artery flow direction and visual deterioration after carotid angioplasty and stenting

OBJECTIVE

Visual deterioration is one of the disabling complications that can occur after carotid angioplasty and stenting (CAS). The purpose of this study was to evaluate the risk factors for newly developed visual symptoms after CAS, focusing on ophthalmic artery (OA) flow pattern and etiology of visual loss.

METHODS

A retrospective review of 127 patients with 138 internal carotid artery (ICA) stenosis lesions that were treated with CAS from February 2009 to October 2017 in a single institution was performed. The flow pattern of the OA was evaluated with digital subtraction angiography and classified into 3 types: type I, antegrade OA flow before and after CAS; type II, antegrade OA flow reversal after CAS; and type III, retained nonantegrade OA flow after CAS.

RESULTS

The degree of ipsilateral ICA stenosis was significantly higher in the nonantegrade group than that in the antegrade group (81.73% ± 9.87% vs 75.74% ± 10.27%, p = 0.001). Independent risk factors for newly developed visual symptoms after CAS were visual symptoms before CAS (OR 65.29, 95% CI 5.14-827.2; p = 0.001) and type III OA flow pattern (OR 55.98, 95% CI 2.88-1088.0; p = 0.008). The post-CAS visual symptoms in 10 patients were related to acute elevation of intraocular pressure in 6 patients and retinal artery occlusion in 3 patients.

CONCLUSIONS

Maintained retrograde or undetected OA flow after CAS and initial visual symptoms before CAS were related to post-CAS visual symptoms. Thus, careful attention is needed for these patients during the perioperative period, and immediate evaluation and management are required for patients with post-CAS visual loss.

The effect of carotid revascularization on the ophthalmic artery flow: systematic review and meta-analysis

INTRODUCTION

High-grade internal carotid stenosis results in impaired flow dynamics in the ocular circulation that may lead to a rare clinical entity; ophthalmic ischemic syndrome (OIS). The aim of this study was to investigate hemodynamic changes in the ophthalmic circulation after carotid revascularization, assessed with duplex ultrasonography (DUS), and their potential impact on ocular function in patients suffering from OIS.

EVIDENCE ACQUISITION

A systematic review of the literature was performed according to the PRISMA guidelines. Medline, Embase and Central databases were searched.

EVIDENCE SYNTHESIS

The analysis included fourteen cohort studies (589 patients) reporting on the hemodynamic effect of carotid revascularization on the ophthalmic circulation using DUS. Eighty-five per cent of patients were treated for symptomatic carotid stenosis. The pre- and postoperative ophthalmological evaluation was recorded in four studies (227 out of 358 patients [63%] diagnosed with OIS). Reversed ophthalmic artery (OA) flow prior to carotid revascularization was present in 86 cases (24%). Following carotid revascularization, a significant increase in peak systolic velocity (PSV) (mean difference [MD] 14.712 cm/s, 95% confidence interval [CI] 10.566-18.858, P<0.001, I²=96%) and a significant anterograde restoration of flow in the OA (OR: 2.047, 95% CI: 1.72-2.42, P<0.001, Ι²=0%) were recorded. Carotid revascularization resulted in regression of ischemic symptoms in 93.1% of patients (95% CI: 56.4-99.3%), P=0.001, I²=82%).

CONCLUSIONS

Carotid revascularization may be associated with a significant flow restoration and PSV increase in the OA; as well as clinical improvement in ischemic ophthalmic symptoms in patients with OIS.

Transient Retinal Ischemia During Carotid Endarterectomy Estimated by Intraoperative Visual Evoked Potential Monitoring: Technical Note

OBJECTIVE

Carotid revascularization surgery is known to carry a risk of postoperative visual deterioration associated with retinal ischemia. We checked intraoperative visual evoked potential (VEP) monitoring in carotid endarterectomy (CEA).

METHODS

Ten consecutive patients who underwent CEA in Shinshu University Hospital under total intravenous anesthesia were checked by intraoperative VEP and electroretinogram (ERG) recording in addition to somatosensory evoked potential monitoring.

RESULTS

Two of 10 patients presented decreased amplitude of VEP and ERG on the ipsilateral affected side by clamping the common carotid artery and persistent attenuation of VEP and ERG during external carotid artery occlusion, using an internal carotid shunt. These findings disappeared immediately after releasing the cervical carotid artery clamping. In the other 8 patients, VEP and ERG did not change throughout the surgery.

CONCLUSIONS

Transient retinal ischemia during even brief carotid artery occlusion in the CEA procedure could be estimated by intraoperative VEP and ERG monitoring.

Carotid Endarterectomy for Ocular Ischemic Syndrome: A Case Report and Review of the Literature

Ocular ischemic syndrome is a rare complication of carotid arterial disease that can lead to irreversible vision loss. The disease is related to ocular hypoperfusion secondary to carotid stenosis. Carotid endarterectomy (CEA) has been proven to reduce the risk of embolic stroke in specific patient populations; however, the role of CEA in the treatment of ocular ischemic syndrome or other flow-related symptoms is less well defined. We present a case of ocular ischemic syndrome successfully treated with carotid endarterectomy, and summarize the current literature regarding management of ocular ischemic syndrome.

[Ophthalmic aspects of vascular and functional changes in malignant arterial hypertension of renal origin]

Malignant arterial hypertension is a clinical syndrome characterized by severe diastolic arterial hypertension with signs of ischemic damage to target organs - kidneys, heart, brain, eyes. Malignant arterial hypertension can be one of the reasons, as well as a consequence of thrombotic microangiopathy - a special type of vascular lesions of the organ microvasculature. Ocular manifestations of arterial hypertension include hypertensive retinopathy of varying severity, choriopathy. The appearance of new diagnostic research methods allows a detailed study of eye damage in malignant arterial hypertension, whether associated or not with thrombotic microangiopathy, and to analyze the relationship of ocular and systemic manifestations of this disease to determine the nature and degree of involvement of the organ of vision in the pathological process and identify prognostic signs of disease progression and its forms.

Significant changes of the choroid in patients with ocular ischemic syndrome and symptomatic carotid artery stenosis

Purpose

To evaluated the changes in choroidal vasculature in patients with ocular ischemic syndrome (OIS) and in the ipsilateral eyes of patients with symptomatic carotid artery stenosis (CAS)

Method

A total of 50 patients (15 patients with OIS, 10 patients with symptomatic CAS, 25 patients of age-and sex-matched control group) were included, and the medical records were retrospectively reviewed. The mean subfoveal choroidal thickness (SFCT) of each eye was measured, and binary images of the choroid were evaluated to compare the mean choroidal area and the luminal area.

Results

The mean SFCT was 170.5±75.3 μm in the eyes with OIS, 154.8±62.9 μm in the ipsilateral eyes with symptomatic CAS, and 277.5±73.2 μm in the right eyes of the control group patients (P<0.001). The mean choroidal area was 494,478.6±181,846.2 μm2 in the eyes with OIS, 453,750.0±196,725.8 μm2 in the ipsilateral eyes with symptomatic CAS, and 720,520±281,319.5 μm2 in the control group eyes (P = 0.036). The mean luminal area was 333,185.7±112,665.9 μm2 in the eyes with OIS, 313,983.3±132,032.1 μm2 in the ipsilateral eyes with symptomatic CAS, and 480,325.0±185,112.6 μm2 in the control group eyes (P = 0.046). The mean SFCT, mean choroidal area, and mean luminal area were significantly smaller in the eyes with OIS (P = 0.017, P = 0.005, and P = 0.004, respectively), and those with symptomatic CAS (P = 0.020, P = 0.016, and P = 0.021, respectively) than in the unaffected contralateral eyes. There were no significant differences between the eyes in the control group (P = 0.984, P = 284, and P = 0.413, respectively).

Conclusion

The mean SFCT, mean choroidal area, and mean luminal area were significantly thinner in the eyes with OIS and the ipsilateral eyes with symptomatic CAS, compared with the control group eyes. The eyes with OIS and those with symptomatic CAS had significantly thinner SFCT, and smaller choroidal area and luminal area than the unaffected contralateral eyes. Choroid may reflect the vascular status of the carotid artery, indicated by choroidal thinning and decreasing choroidal area, especially luminal area.

Optical Coherence Tomography Angiography Evaluation of Retinal Microvasculature Before and After Carotid Angioplasty and Stenting

The aim of the study was to evaluate the influence of carotid angioplasty and stenting (CAS) on retinal microvasculature using optical coherence tomography angiography (OCTA) in patients with severe carotid stenosis. 20 patients with severe carotid stenosis underwent comprehensive ophthalmic examinations and OCTA before and one month after CAS. Automated algorithms were used to quantify vessel density in the macular superficial vascular complex (SVC), deep vascular complex (DVC), and radial peripapillary capillary (RPC) around the optic disc. Eyes on the operated side constituted the ipsilateral eye group, and the other eye constituted the fellow eye group. In the ipsilateral eye group, the vessel density in the DVC increased significantly after stent implantation (P = 0.010), but the vessel density change in the SVC was not statistically different (P = 0.999). In the fellow eye group, the vessel density in the SVC (P = 0.028) and DVC (P = 0.034) were significantly increased after stent implantation. The vessel density in the RPC did not significantly change in the ipsilateral (P = 0.363) or fellow (P = 0.878) eye groups. This study shows that unilateral CAS for severe carotid stenosis increases macular vessel densities in both eyes.

Structural Analysis of the Retina and Choroid before and after Carotid Artery Surgery

Purpose: To evaluate retinal and choroidal changes in patients with internal carotid artery stenosis who had undergone carotid artery stenting or endarterectomy.Methods: The study included 43 patients with internal carotid artery (ICA) stenosis that required stenting or endarterectomy and 40 healthy controls. Patients were divided into two groups according to the degree of stenosis evaluated by magnetic resonance angiography. Group 1 consisted of patients having ICA stenosis of 50 to 70%, and Group 2 has more than 70%. Enhanced depth imaging optical coherence tomography (EDI-OCT) was used to measure the retinal thickness (RT) and choroidal thickness (CT) in all subjects before surgery and at 1, 3, and 6 months after surgery.Results: Subfoveal and parafoveal CT were significantly lower in patients with ICA stenosis than the control group (p < .05, respectively). Patients with 50-70% stenosis had a significant increase in the CT at 1, 3, and 6 months after ICA stenting or endarterectomy (p < .05). Patients with >%70 stenosis did not have a significant increase in the CT at any time after ICA stenting or endarterectomy. Retinal thickness was not statistically different between the patients with ICA stenosis and the control subjects, and RT showed no significant change in patients with ICA stenosis before and after the surgery.Conclusion: Choroidal thickness was significantly thinner in patients with internal carotid artery stenosis. ICA stenting provided a recovery in the choroidal thickness in patients with moderate to advanced stenosis.

Visual Outcome of Carotid Endarterectomy in Patients with Carotid Artery Stenosis

BACKGROUND

Carotid endarterectomy (CEA) is deemed to restore the blood flow of the carotid and ophthalmic arteries in patients with carotid artery stenosis. However, specific changes in visual function before and after CEA are not well understood; hence, this observational study aimed to investigate the functional and structural changes in vision after CEA in those patients.

METHODS

Patients with severe carotid artery stenosis (>70% with standard carotid duplex scanning or arteriography) scheduled to undergo CEA were consecutively recruited for the study between September 2015 and July 2016. All patients underwent a standardized ophthalmic examination, including intraocular pressure (IOP) measurement, slit-lamp examination, and fundus examination. Visual acuity, best corrected visual acuity (BCVA), and kinetic and static visual fields (VFs) were tested to evaluate subjective visual function. Flash and pattern visual evoked potentials (VEPs) and an electroretinogram (ERG) were measured for objective visual function. Retinal nerve fiber layer (RNFL) thickness was scanned using optical coherence tomography for structural evaluation.

RESULTS

The study involved 15 patients (11 male and 4 female, corresponding to 30 eyes; mean age 62.8 ± 5.0 years). After CEA, both uncorrected visual acuity and BCVA improved, and IOP significantly decreased from 17.41 ± 2.59 to 15.95 ± 2.50 mm Hg (P = 0.0022). Kinetic VF range increased significantly (P = 0.0126) as did mean sensitivity from 18.8 ± 5.5 to 20.6 ± 4.3 dB (P = 0.0208), whereas mean defect decreased from 8.2 ± 5.3 to 6.5 ± 4.2 dB (P = 0.025). RNFL thickness was not significantly altered. Latency of the P2 wave on flash VEP reduced significantly after CEA (P = 0.0151), whereas the oscillatory potential amplitude of waveform 3 in the ERG significantly increased after CEA.

CONCLUSIONS

Our results demonstrate that an improvement in carotid artery and ophthalmic artery blood flow after CEA does indeed enhance subjective and objective assessments of visual function in patients with carotid artery stenosis, including visual acuity, kinetic and static VF, P2 latency, and ocular pressure amplitude; however, it did not affect RNFL thickness.

Carotid Artery Endarterectomy Effect on Choroidal Thickness: One-Year Follow-Up

Purpose

To evaluate the change in choroidal thickness after carotid artery endarterectomy (CEA) in patients without retinal pathology.

Methods

A prospective series of patients who underwent CEA at the Tel Aviv Medical Center. Spectral domain optical coherence tomography (SD-OCT) was performed one day before the CEA and at least 6 months after. Data included medical history, smoking history, percentage of carotid stenosis before and after CEA, best-corrected visual acuity (BCVA), central macular thickness (CMT), and choroidal thickness (subfoveal, 500 µm, 1000 µm, and 1500 µm nasal and temporal).

Results

Eight patients (seven male and one female) with a mean age of 70.5 ± 6.1 years were included in the study. The mean internal carotid artery (ICA) stenosis was 89.8% ± 5.1 in the operated side, 33.7% ± 10.9 in the nonoperated side (p < 0.0001), and 0% after CEA (p < 0.0001). Operated side BCVA was 0.35 ± 0.66 compared to 0.61 ± 0.83 in the nonoperated side (p=0.51). The mean subfoveal choroidal thickness (SFChT) of the operated side was 277 ± 67 µm compared to 268 ± 71 µm in the nonoperated side (p=0.81). SFChT and CMT after CEA were 275 ± 64 µm (p=0.96) and 268 ± 29 µm (p=0.98), respectively.

Conclusions

SFChT and CMT in patients without retinal or choroidal pathology and significant ICA stenosis can be normal and may not change after successful ipsilateral CEA.

Retinal ganglion cell complex and peripapillary retinal nerve fiber layer thicknesses following carotid endarterectomy

PURPOSE

To examine changes in retinal ganglion cell complex (GCC) and peripapillary retinal nerve fiber layer (RNFL) thicknesses by optical coherence tomography (OCT) in contralateral and ipsilatateral eyes of carotid artery stenosis (CAS) patients before and after carotid endarterectomy (CEA).

METHODS

Forty-two consecutive patients diagnosed with CAS (70-99% stenosis rate) who underwent CEA were included in this prospective cross-sectional study. The indication for CEA was based on the Asymptomatic Carotid Atherosclerosis Study. Doppler ultrasonography and computed tomography angiography were performed to calculate CAS. All the subjects underwent an ophthalmological examination, including best corrected visual acuity (BCVA), intraocular pressure (IOP) measurements, biomicroscopy, fundoscopy, and OCT before and after the surgery.

RESULTS

The mean preoperative intraocular pressure was 15.2 ± 2.1 mmHg in the ipsilateral eye and 15.8 ± 2.7 in the contralateral eye. The mean postoperative intraocular pressure in the ipsilateral and contralateral eye was 18.6 ± 3.0 and 19.3 ± 3.8, respectively. The intraocular pressure was significantly higher in postoperative eyes (p = 0.0001). There was a statistically significant decrease in peripapillary RNFL thickness in superior quadrants postoperatively in ipsilateral eyes. The retinal GCC layer thickness was not significantly different before and after CEA in ipsilateral and contralateral eyes.

CONCLUSIONS

Carotid endarterectomy results in thinning of the superior peripapillary RNFL thickness. To the best of our knowledge, this is the first study to examine peripapillary RNFL and GCC thicknesses before and after CEA.

Relationship between the Direction of Ophthalmic Artery Blood Flow and Ocular Microcirculation before and after Carotid Artery Stenting

When internal carotid artery stenosis is accompanied by ocular ischemic syndrome, intervention is recommended to prevent irreversible visual loss. In this study, we used laser speckle flowgraphy to measure the ocular microcirculation in the optic nerve head before and after carotid artery stenting (CAS) of 40 advanced internal carotid stenosis lesions from 37 patients. The aim was to investigate the relationship between ocular microcirculation and the direction of ophthalmic artery blood flow obtained by angiography. We found that there was a significant increase in blood flow after CAS (P = 0.003). Peak systolic velocity as an indicator of the rate of stenosis was also significantly higher in the group with retrograde/undetected flow of the ophthalmic artery than in the group with antegrade flow (P = 0.002). In all cases where retrograde flow of the ophthalmic artery was observed before stenting, the flow changed to antegrade after stenting. Through the use of laser speckle flowgraphy, this study found that CAS can improve ocular microcirculation. Furthermore, while patients displaying retrograde flow of the ophthalmic artery before stenting have a poor prognosis, CAS corrected the flow to antegrade, suggesting that visual loss can be prevented by improving the ocular microcirculation.

Changes in chorioretinal blood flow velocity and cerebral blood flow after carotid endarterectomy

PURPOSE

To investigate the changes in chorioretinal blood flow velocity and cerebral blood after carotid endarterectomy (CEA).

METHODS

Nine patients with moderate to severe internal carotid artery stenosis underwent CEA. Chorioretinal blood flow velocity was measured by laser speckle flowgraphy (LSFG), while cerebral blood flow (CBF) was measured by single-photon emission computed tomography (SPECT), on the affected side both before and after CEA. LSFG was evaluated in five areas to determine mean blur rate, while CBF was calculated from regional CBF and cerebrovascular reactivity (CVR), at the middle cerebral artery (MCA) region of each patient.

RESULTS

Five cases showed an increase (mean 3.49 %, range -29.82 to 35.59 %) of average chorioretinal blood flow velocity using LSFG after CEA. A particularly averaged increase in chorioretinal blood flow was observed in the macular area compared with other areas. Similarly, there was an increase in CBF at rest (mean 11.46 %, range -14.51 to 74.14 %) observed using SPECT after surgery. Improvement of CVR was confirmed in four cases. All general and visual symptoms disappeared after CEA. Severe adverse effects, including hyperperfusion syndrome, were not observed in any cases.

CONCLUSIONS

LSFG may be useful for the analysis of chorioretinal blood flow changes after CEA.

Central retinal artery occlusion following laser treatment for ocular ischemic aortic arch syndrome

OBJECTIVE

Ocular ischemic syndrome is a rare blinding condition generally caused by disease of the carotid artery. We describe a 69-year-old female with a 50 pack-year smoking history with aortic arch syndrome causing bilateral ocular ischemic syndrome.

METHODS

The patient presented with progressive visual loss and temple pain. Slit lamp biomicroscopy revealed bilateral iris neovascularization. This finding prompted a cardiovascular work up. Panretinal photocoagulation with retrobulbar block was performed in the right eye.

RESULTS

A temporal artery biopsy was negative. The carotid duplex ultrasound showed only a 1-39% stenosis. MRA revealed a more proximal occlusion of the aortic branch for which she underwent subclavian carotid bypass surgery. At the one month follow up, the right eye suffered profound vision loss secondary to a central retinal artery occlusion.

CONCLUSION

Ocular neovascularization may be one of the clinical manifestations of aortic arch syndrome. This case also illustrates the limitations of relying solely on carotid duplex ultrasound testing. We caution against overly aggressive panretinal photocoagulation utilizing retrobulbar anesthesia.