Hypertension Likely Drives Arteriolar Wall Thickening in Preclinical Diabetic Retinopathy While Diabetes Drives Wall Thickness in Clinical Retinopathy.

Purpose: Both hypertension and diabetes are known to increase the wall-to-lumen ratio (WLR) of retinal arterioles, but the differential effects are unknown. Here, we study the timing and relative impact of hypertension versus diabetes on the WLR in diabetic retinopathy (DR) to address this unresolved question. Methods: This prospective cross-sectional study compared the retinal arteriolar WLR in 17 healthy eyes, 15 with diabetes but no apparent DR (DM no DR), and 8 with diabetic macular edema (DME) and either nonproliferative or proliferative DR. We imaged each arteriole using adaptive optics scanning laser ophthalmoscopy and measured the WLR using ImageJ. Multiple linear regression (MLR) was performed to estimate the effects of hypertension, diabetes, and age on the WLR. Results: Both subjects with DM no DR and subjects with DME had significantly higher WLR than healthy subjects (0.36 ± 0.08 and 0.42 ± 0.08 vs. 0.29 ± 0.07, 1-way ANOVA P = 0.0009). MLR in healthy subjects and subjects with DM no DR showed hypertension had the strongest effect (regression coefficient = 0.08, P = 0.009), whereas age and diabetes were not significantly correlated with WLR. MLR in all three groups together (healthy, DM no DR, and DME) showed diabetes had the strongest effect (regression coefficient = 0.05, P = 0.02), whereas age and hypertension were not significantly correlated with WLR. Conclusions: Hypertension may be an early driver of retinal arteriolar wall thickening in preclinical DR, independent of age or diabetes, whereas changes specific to DR may drive wall thickening in DME and later DR stages. Translational Relevance: We offer a framework for understanding the relative contributions of hypertension and diabetes on the vascular wall, and emphasize the importance of hypertension control early in diabetes even before DR onset.

Investigation of alterations in retrobulbar hemodynamics and their correlation with choroidal thickness after strabismus surgery.

BACKGROUND: To evaluate the changes in retrobulbar circulation after strabismus surgery and to assess the relationship of these changes with choroidal thickness (CT). METHODS: This prospective study included 26 eyes of 26 patients who underwent strabismus surgery and 15 eyes of 15 healthy individuals as control group. The patients who had single horizontal muscle surgery were included in Group 1 (n = 14); and those who had surgery on both horizontal muscles were included in Group 2 (n = 12). Peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI) and pulsatility index (PI) of ophthalmic artery (OA), posterior ciliary artery (PCA), and central retinal artery (CRA) were measured using Color Doppler Ultrasonography. Subfoveal CT was measured via Optical Coherence Tomography. All measurements were obtained preoperatively, at 1st week and 1st month after surgery. RESULTS: There were no differences regarding preoperative blood flow velocity parameters among the groups. OA RI increased significantly at 1st week and 1st month after surgery in Group 1 and 2 (P = 0.029 and P = 0.045, respectively). There was a significant increase in PCA PSV at 1st week in Group 1 (P = 0.002). There was no difference between the mean preoperative and postoperative CT among the 3 groups. A negative correlation between the percentage changes of CT and CRA EDV was found in Group 2 (P = 0.011). CONCLUSION: Single and double horizontal rectus muscle surgery have a measurable effect on retrobulbar hemodynamics but these changes do not correlate with CT.

Ultrawide Field Imaging of Progressive Retinal Arteriovenous Malformation in a Pediatric Patient with Wyburn-Mason Syndrome.

Wyburn-Mason syndrome (WMS) is a rare congenital disease that presents with unilateral arteriovenous malformation (AVM) in the visual pathway, midbrain, and/or skin. We report a case of a 5-year-old girl with a history of cerebral and orbital AVM who presented with left exotropia and was found to have group 3 retinal AVM consistent with WMS. Here, we use ultrawide field imaging to show the progression of retinal AVM and peripheral nonperfusion areas for a period of 1 year in a pediatric patient with WMS. [Ophthalmic Surg Lasers Imaging Retina. 2022;53:46-48.].

Retinal detachment following focal laser to ruptured retinal artery macro aneurysm.

A 53-year-old lady presented with inferior retinal detachment (RD) following focal laser for retinal artery macroaneurysm (RAM). She underwent focal laser with intravitreal gas injection elsewhere; however, no retinal break was localized on the examination. The patient was taken up for vitreoretinal surgery. Intraoperatively, it was noted that the retinal detachment was not extending to the retinal periphery and primary retinal break was not localized even during the scleral depression. Under high magnification, using a macular lens, a slit-like retinal break was noted at the area of previous focal laser. Focal laser for RAM probably caused this retinal break leading to RD. The clinician needs to be aware that during focal laser of ruptured RAM, haemorrhage may preclude the view of retinal structures leading to inadvertent use of excessive laser energy. Retinal breaks may form at the site of laser due to coagulative necrosis. During surgical management of RD in such cases, the area of focal laser should be thoroughly examined under high magnification to avoid missed breaks.

Management of Central Retinal Artery Occlusion: A Scientific Statement From the American Heart Association.

PURPOSE: Central retinal artery occlusion (CRAO) is a form of acute ischemic stroke that causes severe visual loss and is a harbinger of further cerebrovascular and cardiovascular events. There is a paucity of scientific information on the appropriate management of CRAO, with most strategies based on observational literature and expert opinion. In this scientific statement, we critically appraise the literature on CRAO and provide a framework within which to consider acute treatment and secondary prevention. METHODS: We performed a literature review of randomized controlled clinical trials, prospective and retrospective cohort studies, case-control studies, case reports, clinical guidelines, review articles, basic science articles, and editorials concerning the management of CRAO. We assembled a panel comprising experts in the fields of vascular neurology, neuro-ophthalmology, vitreo-retinal surgery, immunology, endovascular neurosurgery, and cardiology, and document sections were divided among the writing group members. Each member received an assignment to perform a literature review, synthesize the data, and offer considerations for practice. Multiple drafts were circulated among the group until consensus was achieved. RESULTS: Acute CRAO is a medical emergency. Systems of care should evolve to prioritize early recognition and triage of CRAO to emergency medical attention. There is considerable variability in management patterns among practitioners, institutions, and subspecialty groups. The current literature suggests that treatment with intravenous tissue plasminogen activator may be effective. Patients should undergo urgent screening and treatment of vascular risk factors. There is a need for high-quality, randomized clinical trials in this field.

Incidence of cilioretinal arteries in 11- to 12-year-old children and association with maternal smoking during pregnancy: the Copenhagen Child Cohort 2000 Eye Study.

PURPOSE: To estimate the incidence of cilioretinal arteries in a Danish child cohort and associations with birth parameters. METHODS: The population-based Copenhagen Child Cohort 2000 Eye Study examined 1406 children aged 11-12 years. Colour fundus images of both eyes were graded for cilioretinal arteries in the three categories large temporal (defined as supplying the central macula), small temporal and nasal. Data on maternal smoking during pregnancy, gestational ageand birth weight were obtained from the Danish Medical Birth Registry. RESULTS: A total of 463/1338 (35%) children were found to have one or more cilioretinal arteries per child. Large temporal cilioretinal arteries were present in 280/1338 (21%) of children and were associated with tobacco smoking during pregnancy, being present in 70/246 (28%) of children with mothers who were smoking during pregnancy, but only in 191/990 (19%) of children whose mothers did not smoke during pregnancy (p = 0.0022). After adjustments for potential confounders, the odds ratio of having one or more large temporal cilioretinal arteries was 1.72 (CI95% 1.19-2.47; p = 0.0035) in the smoking versus none smoking category. No other associations with birth parameters were found. CONCLUSION: Cilioretinal arteries were present in more than one third of 11- to 12-year-old Danish children. Large temporal cilioretinal arteries were found in one fifth of children and were associated with maternal smoking during pregnancy. This finding suggests that the intrauterine environment may have an impact on the development of retinal vessels during foetal life.

Site of Origin of the Ophthalmic Artery Influences the Risk for Retinal Versus Cerebral Embolic Events.

BACKGROUND: Embolic events leading to retinal ischemia or cerebral ischemia share common risk factors; however, it has been well documented that the rate of concurrent cerebral infarction is higher in patients with a history of transient ischemic attack (TIA) than in those with monocular vision loss (MVL) due to retinal ischemia. Despite the fact that emboli to the ophthalmic artery (OA) and middle cerebral artery share the internal carotid artery (ICA) as a common origin or transit for emboli, the asymmetry in their final destination has not been fully explained. We hypothesize that the anatomic location of the OA takeoff from the ICA may contribute to the differential flow of small emboli to the retinal circulation vs the cerebral circulation. METHODS: We report a retrospective, comparative, case-control study on 28 patients with retinal ischemia and 26 patients with TIA or cerebral infarction caused by embolic events. All subjects underwent either computed tomography angiography or MRA. The location of the ipsilateral OA origin off the ICA was then graded in a blinded fashion and compared between cohorts. Vascular risk factors were collected for all patients, including age, sex, hypertension, hyperlipidemia, arrhythmia, diabetes, coronary artery disease, and smoking. RESULTS: We find that in patients with retinal ischemia of embolic etiology, the ipsilateral OA takeoff from the ICA is more proximal than in patients with cerebral infarcts or TIA (P = 0.0002). We found no statistically significant differences in demographic, vascular, or systemic risk factors. CONCLUSIONS: We find that the mean anatomical location of the OA takeoff from the ICA is significantly more proximal in patients with MVL due to retinal ischemia compared with patients with TIA or cerebral ischemia. This finding contributes significantly to our understanding of a long observed but poorly understood phenomenon that patients with MVL are less likely to have concurrent cerebral ischemia than are patients with TIA.

Multimodal imaging in pediatric arterial macroaneurysm: A case report.

Our aim is to report a case of asymptomatic retinal arterial macroaneurysm in a 9-year-old female patient. She was referred to our Ophthalmology clinic for a routine ophthalmologic examination and, after the detection of a juxtafoveal saccular vascular enlargement in indirect ophthalmoscopy, underwent a multimodal imaging assessment. Optical coherence tomography-angiography and fluorescein angiography were important to determine the nature of the lesion, identified as a congenital retinal arterial macroaneurysm. Retinal vascular abnormalities represent a rare finding in pediatric patients and must be carefully explored to establish the correct diagnosis. A multimodal imaging approach was very useful to thoroughly reach this target. Vascular abnormalities represent a rare finding in pediatric patients and must be carefully explored to establish the correct diagnosis. A multimodal imaging approach is very useful to study in deep the reported arterial macroaneurysm in a non-invasive way.

Hemodynamics of the temporal and nasal short posterior ciliary arteries in pseudoexfoliation syndrome.

PURPOSE: The aim of this study was to investigate blood flow changes in the temporal and nasal short posterior ciliary arteries (SPCAs) in pseudoexfoliation syndrome using color Doppler ultrasonography. METHODS: This prospective clinical study included 67 eyes of 53 patients scheduled for cataract surgery. Pseudophakic eyes, eyes with traumatic cataract, were excluded. The demographic characteristic of the patients were recorded. Ocular blood flow was measured using 6-10 MHz Doppler ultrasound. Peak systolic velocity (PSV), end-diastolic velocity (EDV), mean flow velocity (Vm), and resistive index (RI) in the temporal and nasal SPCAs were determined for 39 eyes of 30 patients with pseudoexfoliation syndrome and cataract and a control group comprising 28 eyes of 23 patients with senile cataract. RESULTS: Compared to the control group, patients with pseudoexfoliation syndrome had significantly lower PSV (8.85 ± 2.88 cm/s), EDV (3.21 ± 1.12 cm/s), and Vm (5.27 ± 1.98 cm/s) in the temporal SPCA (PSV P = .001; EDV P = .002; Vm P = .001). There was no difference in velocities in the nasal SPCA. RI of both the temporal and nasal SPCA did not differ statistically between the groups (temporal SPCA P = .517, nasal SPCA P = .752) CONCLUSION: There were significant decreases in temporal SPCA hemodynamic parameters in patients with pseudoexfoliation syndrome. These findings suggest that temporal SPCA ocular blood flow measurements have greater diagnostic value than those of the nasal SPCA.

Ophthalmic artery resistance index after peribulbar block in the presence of epinephrine.

PURPOSE: There are controversies regarding ophthalmic artery (OA) flow after peribulbar block in the presence of epinephrine. Therefore, we aimed to evaluate OA flow via echo-Doppler before and after peribulbar block with lidocaine in the presence or absence of epinephrine. METHODS: Fifty-six patients who had an American Society of Anesthesiologists (ASA) classification of I, II or III and were eligible for cataract phacoemulsification surgery were selected. Patients with other eye diseases were excluded. Patients were divided into two groups: group 1-peribulbar block with lidocaine and 1/200,000 epinephrine; group 2-peribulbar block with lidocaine in the absence of epinephrine. The resistance index (RI), peak systolic velocity (PSV), end diastolic velocity (EDV) of the OA were evaluated using echo-Doppler before and 10 min after the peribulbar block. RESULTS: No differences between groups were observed in the RI before the peribulbar block as well regarding the presence of hypertension and the age or gender of the patient. After the peribulbar block, we observed a decrease in the RI in group 1 (p = 0.038, Cohen's d = 0.336) and no difference in the RI in group 2 (p = 0.109, Cohen's d = 0.172). When comparing group 1 and group 2, we observed a decrease in the RI in group 1 (p = 0.028, Cohen's d = 0,583). There was no difference between groups regarding the PSV and EDV after the peribulbar block. CONCLUSIONS: A decrease in RI was observed in the OA after peribulbar block with a vasoconstrictor, an effect that could be a benefit in some ocular surgeries.

Impact of Radioiodine Treatment on Doppler Flow Parameters in the Central Retinal Artery and Ophthalmic Artery in Patients With Hyperthyroidism.

OBJECTIVES: The aim of this study was to identify changes in Doppler flow parameters in the central retinal artery (CRA) and ophthalmic artery (OA) that could be indicative of de novo development of thyroid-associated orbitopathy in the early period after radioiodine treatment. METHODS: Eighty-two patients with hyperthyroidism were enrolled: 44 with Graves disease and 38 with toxic nodular goiter. In both groups, blood flow parameters in the CRA and OA were analyzed before and 2 and 4 weeks after radioiodine administration. The peak systolic velocity and end-diastolic velocity (EDV) were evaluated, and the resistive index (RI) was calculated. RESULTS: There were no statistically significant differences in the peak systolic velocity, EDV or RI between groups at baseline and 4 weeks after radioiodine administration. Two weeks after radioiodine administration, the RI in the CRA (P = .034) and EDV in the OA (P = .026) were significantly lower, and the EDV in the CRA (P = .004) was higher in patients with Graves disease than in patients with toxic nodular goiter. There was an inverse correlation between baseline thyrotropin receptor autoantibody (TRAb) levels and the difference between the RI at weeks 4 and 2 (RI3-RI2) in the CRA (r = -0.458; P < .05) and a positive correlation between the baseline anti-thyroid peroxidase antibody concentration and RI3-RI2 in the OA (r = 0.435; P < .05). CONCLUSIONS: Administration of radioiodine results in more prominent features of hyperkinetic circulation. Patients with Graves disease and high TRAb titers have a lower sensitivity to radioiodine treatment. High TRAb titers suggest higher disease activity and a weaker therapeutic effect of radioiodine.

The Natural History of Retinal Vascular Changes from Infancy to Adulthood in Wyburn-Mason Syndrome.

Wyburn-Mason syndrome is a rare, non-hereditary congenital neurocutaneous disorder leading to arteriovenous malformations. Malformations are characterized by an artery that is directly connected to veins without a capillary system and forms a fragile mass of abnormal vessels. It can be found in the midbrain, in the eyes, orbit, and rarely in cutaneous nevi. Neurological and ocular symptoms are the most common. Ocular signs and symptoms include abnormally dilatated vessels of conjunctiva, nystagmus, strabismus, vitreous hemorrhage, vein occlusions, retinal detachment, etc. Neurological symptoms may include headaches, paralysis, epistaxis, hydrocephalus, and hemiparesis. Imaging modalities such as MRI/CT angiography, optical coherence angiography, and fluorescein angiography are the most important for the identification of arteriovenous malformations. In our case report, we present an eight-month-old girl with an incidental finding of retinal angiomatosis on the left eye and was subsequently diagnosed with Wyburn-Mason syndrome. We compare the findings from the first visit to her clinical findings 20 years later.

Detection of Occult Arteriovenous Malformation With Annular Array Ultrasonography.

Retinal vascular tortuosity may occur in a wide range of ocular disorders. When retinal vascular tortuosity involves both arteries and veins, and presents unilaterally and without hemorrhage, a diagnosis of Wyburn Mason syndrome (WMS) should be considered due to the potential morbidity and mortality associated with cerebral involvement. Magnetic resonance imaging (MRI) and MRI angiography (MRA) are important tools for identifying cerebral arteriovenous malformations (AVMs), but these imaging modalities have limited spatial resolution to detect very small vascular lesions. Annular array contact ocular ultrasound is a new imaging modality capable of detecting small intraorbital AVMs. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:239-243.].

Sonographic assessment of the optic nerve and the central retinal artery in idiopathic intracranial hypertension.

PURPOSE: Transorbital sonography easily detects papilledema and enlarged optic nerve sheath diameters (ONSD) in IIH (idiopathic intracranial hypertension) patients. As the central retinal artery is located within the optic nerve, its hemodynamic properties might be affected by the increased pressure. In this study we assessed the diagnostic usefulness of transorbital sonography in IIH with a special focus on color Doppler imaging of the central retinal artery. IIH patients presented papilledema and enlarged ONSD. ONSD accurately predicted an increased intracranial pressure in IIH (cut-off: 5.8 mm, 81% sensitivity, 80% specificity). 24 h following therapeutic lumbar puncture ONSD diminished significantly, whereas papilledema was not changed. PSV (peak systolic velocity) and Vmean (mean flow velocity) of the central retinal artery were increased in IIH patients compared to controls. PSV accurately predicted an increase of intracranial pressure (cut-off: 11.0 cm/s, 70% sensitivity, 69% specificity). PI (pulsatility index), PSV and Vmean decreased following lumbar puncture. PSV and Vmean decreases were statistically significant for right eyes only in which the values changed to normal. In summary, besides ONSD enlargement and papilledema transbulbar sonography demonstrated an alteration of central retinal artery blood flow in IIH patients. Especially PSV might serve as valuable surrogate marker for intracranial pressure in IIH. Furthermore, the change of intra-individual central retinal arteries PI might be a valuable parameter to demonstrate response to lumbar puncture in IIH patients.

Waveform parameters of retrobulbar vessels in glaucoma patients with different demographics and disease severity.

INTRODUCTION: To identify novel velocity waveform parameters of the ophthalmic artery and central retinal artery by computer-aided image processing of Doppler ultrasonography measurements, and to evaluate correlations between the waveform parameters and different demographics and disease severity of open-angle glaucoma patients. METHODS: Thirty-six images of 36 open-angle glaucoma patients were considered. A semiautomated image processing code was used to detect the digitalized ophthalmic artery and central retinal artery velocity waveforms and to extract the waveform parameters. Concordance correlation coefficient, two-sample t-test, and Pearson's correlation coefficient were used to test for similarities, differences, and associations among variables. RESULTS: Female glaucoma patients showed a statistically higher ophthalmic artery normalized distance between ascending and descending limb (p = 0.004), hypertensive glaucoma patients a statistically higher ophthalmic artery peak systolic velocity time (p = 0.025), glaucoma patients with hyperlipidemia a statistically higher ophthalmic artery resistivity index (p = 0.023) and a statistically higher ophthalmic artery peak systolic velocity acceleration (p = 0.025), glaucoma patients with cardiovascular diseases a statistically lower central retinal artery normalized distance between ascending and descending limb of the wave (p = 0.033) and a statistically higher central retinal artery period (p = 0.028), and patients with different body mass index a statistically different central retinal artery normalized distance between ascending and descending limb of the wave (p = 0.016). Groups with different disease severity, classified following the Brusini glaucoma staging system 2, showed statistically different central retinal artery normalized distance between ascending and descending limb of the wave (p < 0.001) and central retinal artery period (p = 0.016). No statistical differences were found in regard to race, diabetes status, glaucoma family history, and smoking. DISCUSSION: Ophthalmic artery and central retinal artery computer-aided analysis of velocity waveforms could identify novel waveform parameters capable of differentiating among different demographics and disease severity of open-angle glaucoma patients.