Ophthalmodynamometric differences between ischemic vs nonischemic retinal vein occlusion

PURPOSE: To estimate the central retinal vein pressure in patients with ischemic vs nonischemic central retinal vein occlusion (CRVO). DESIGN: Prospective clinical observational comparative study. METHODS: The study included 28 patients with CRVO, either of the ischemic type (n = 7) or the nonischemic type (n = 21). The control group consisted of 38 subjects without retinal disease. A new ophthalmodynamometer consisting of a Goldmann contact lens fitted with a pressure sensor into the holding grip of the contact lens, was used to indirectly estimate the central retinal artery and vein pressure. RESULTS: Central retinal vein pressure was significantly higher in the ischemic CRVO group than in the nonischemic CRVO group (91.5 +/- 30.1 arbitrary units vs 52.4 +/- 32.5 arbitrary units; P = .014), in which it was significantly (P < .001) higher than in the control group (4.8 +/- 8.1 arbitrary units). Central retinal vein pressure was higher than the diastolic central retinal artery pressure significantly (P = .039) more frequently in the ischemic CRVO group (7/7 or 100%) than in the nonischemic CRVO group (8/21 or 38%) or the control group (0/38; P < .001). Central retinal artery pressure was significantly (P = .017) lower in the ischemic CRVO group (46.0 +/- 10.6 arbitrary units) than in the nonischemic CRVO group (64.5 +/- 22.8 arbitrary units), in which it was significantly (P = .016) lower than in the control group (79.9 +/- 22.3 arbitrary units). CONCLUSIONS: Ophthalmodynamometric estimation of the retinal vein pressure may be helpful for the differentiation between the ischemic vs nonischemic type of CRVO. In the ischemic type, vein pulsations were usually observed at supradiastolic arterial values.     

Blood-aqueous barrier in eyes with retinal vein occlusion.

PURPOSE: The purpose of this study is to examine the changes of blood-aqueous barrier function in cases of central or branch retinal vein occlusion. METHODS: In addition to fluorophotometry of the aqueous humor and posterior vitreous, the authors used a method that quantifies protein in the aqueous (aqueous flare) by measuring the intensity of scattered laser light. RESULTS: Aqueous and posterior vitreous fluorescein concentrations and aqueous flare were significantly higher than in unaffected fellow eyes or eyes of visually normal age-matched controls both in central and branch retinal vein occlusions. They also were significantly higher in eyes with central vein occlusion than in those with branch vein occlusion. Among those eyes with central vein occlusion, aqueous and posterior vitreous fluorescein concentrations and aqueous flare were significantly higher in the hemorrhagic than in the venous stasis type of disease. Among eyes with branch vein occlusion, cases at the acute stage showed significantly higher amounts of aqueous and posterior vitreous fluorescein concentrations and aqueous flare than did those with chronic occlusion. CONCLUSION: The authors believe that increased amounts mainly reflect blood-ocular barrier disruption. Not only the blood-retinal barrier but also the blood-aqueous barrier disruption is a common sequela in the disorder.     

Central retinal artery and vein collapse pressure in eyes with chronic open angle glaucoma

AIMS: To determine central retinal vessel collapse pressure in chronic open angle glaucoma. METHODS: For 19 eyes with chronic open angle glaucoma and 27 eyes of a control group, central retinal vessel collapse pressure was measured by a Goldmann contact lens fitted with a pressure sensor in its holding grip. RESULTS: Central retinal vein collapse pressure was significantly (p=0.001) higher in the glaucoma group than in the control group (26.1 (SD 26.4) relative units versus 6.1 (8.4) relative units). CONCLUSIONS: Measured by a new ophthalmodynamometer, central retinal vein collapse pressure measurements may be abnormally high in eyes with chronic open angle glaucoma.     

Ophthalmodynamometric determination of the central retinal vessel collapse pressure correlated with systemic blood pressure

AIMS: To evaluate whether determination of the central retinal artery and vein collapse pressure correlate with systemic blood pressure measurements, using a new Goldmann contact lens associated ophthalmodynamometric device METHODS: The prospective clinical study included 92 eyes of 92 patients presenting with cataract or refractive problems (n = 40; control study group) or with retinal and orbital pathologies (n = 52). With topical anaesthesia, a Goldmann contact lens fitted with a pressure sensor in its holding ring was placed onto the cornea. Pressure was asserted onto the globe by pressing the contact lens, and the pressure value at the time when the central retinal artery and vein started pulsating were noted as central retinal artery and vein collapse pressure. Additionally, the brachial arterial blood pressure was measured. RESULTS: In the control study group, central retinal artery collapse pressure was highly significantly correlated with diastolic blood pressure (correlation coefficient r = 0.77; p<0.001) and systolic blood pressure (r = 0.35; p = 0.03). Central retinal vein collapse pressure was statistically independent of diastolic blood pressure (p = 0.11). In eyes with retinal or orbital diseases, the correlation coefficients were lower than in the control study group. In eyes with retinal arterial occlusions, central retinal vessel collapse pressure measurements were not correlated with arterial blood pressure measurements. CONCLUSIONS: Depending on coexisting retinal or orbital diseases, ophthalmodynamometric estimation of the central retinal artery collapse pressure, performed during a routine Goldmann contact lens ophthalmoscopy, correlates with systemic blood pressure measurements.     

Ophthalmodynamometry in eyes with dilated episcleral veins

PURPOSE: To determine the central retinal vessel collapse pressure in patients with dilated episcleral veins. METHODS: This clinical noninterventional comparative study included a study group of 10 eyes (6 patients) with dilated episcleral veins, and a control group consisting of 50 eyes of 40 patients with cataract or refractive problems. With topical anesthesia, a Goldmann contact lens fitted with a pressure sensor in its holding ring was placed onto the cornea. Pressure was asserted onto the globe by pressing the contact lens, and the pressure value at the time when the central retinal artery and vein started pulsating was noted as central retinal artery and vein collapse pressure. RESULTS: Central retinal vein collapse pressure was significantly higher (P<0.001) in the study group with dilated episcleral veins than in the control group (37.9 +/- 33.8 vs 5.1 +/- 8.4 relative units [RU]). In the central retinal artery, there was not significant difference in diastolic collapse pressure measured between the study and control groups (78.2 +/- 22.8 vs 74.2 +/- 18.8 RU, respectively; P = 0.74). CONCLUSIONS: As measured by a new ophthalmodynamometer with biomicroscopic visualization of the central retinal vessels during the examination, the central retinal vein collapse pressure measurements were significantly higher in eyes with dilated episcleral veins than in control eyes. Ophthalmodynamometric estimation of the central retinal vein collapse pressure may be helpful in the assessment of patients with dilated episcleral veins.     

Reproducibility of ophthalmodynamometric measurements of central retinal artery and vein collapse pressure

BACKGROUND: To assess the reproducibility of ophthalmodynamometric measurements using a new, Goldmann contact lens associated, device allowing biomicroscopic visualisation of the optic disc. METHODS: The prospective clinical study included 87 eyes of 58 subjects presenting with a normal fundus (n=40), or ocular diseases (n=47). With topical anaesthesia, a Goldmann contact lens, fitted with a pressure sensor mounted into the holding ring of the contact lens, was placed onto the cornea. Pressure was applied onto the globe through the contact lens, and the pressure values obtained when the central retinal vessels started pulsating were noted. The measurements were performed 10 times. RESULTS: The mean coefficients of variation for redeterminations of the collapse pressure of the central retinal vein and artery were 16.3% (SD 11.4%), and 8.5% (4.1%), respectively. CONCLUSIONS: A simple and new, Goldmann contact lens associated, ophthalmodynamometer allows central retinal artery and vein collapse pressure measurements which are reproducible in a clinical setting.     

Ophthalmodynamometry of central retinal vein collapse pressure in idiopathic intracranial hypertension

BACKGROUND: The diagnosis of idiopathic intracranial hypertension results from a synopsis of standardised examinations including MRI. Since the cerebrospinal fluid pressure influences the pressure of the central retinal vein, it was the purpose of the present study to evaluate whether the ophthalmodynamometric estimation of the central retinal vein collapse pressure is helpful for the diagnosis of idiopathic intracranial hypertension. PATIENTS AND METHODS: The study included 5 patients with idiopathic intracranial hypertension with a mean age of 38.3+/-10.8 years and 88 subjects of a control group with a mean age of 66.8+/-13.1 years. Using a modified corneal contact lens-associated ophthalmodynamometry, the collapse pressure of the central retinal vein was estimated. RESULTS: The central retinal vein collapse pressure was significantly higher in the study group (33.0+/-27.3 relative units) than in the control group (2.0+/-6.7 relative units) (p<0.006; 95 % confidence interval: -11.5, 50.5). The central retinal artery collapse pressure did not vary significantly between the two groups (52.7+/-15.3 relative units versus 65.6+/-20.4 relative units; p=0.19; 95 % confidence interval: -36.6, 10.5). CONCLUSIONS: The corneal contact lens-associated ophthalmodynamometry can be helpful for the monitoring of patients with intracranial idiopathic hypertension.     

Vitrectomy prevents retinal hypoxia in branch retinal vein occlusion

Vitrectomy has been shown to halt diabetic retinal neovascularization, but the mechanism of this process is unknown. We propose that vitrectomy improves the oxygen supply to ischemic inner retina by way of fluid currents in the vitreous cavity. In order to test this hypothesis, we induced branch retinal vein occlusion in cats and measured preretinal oxygen tension before and after branch retinal vein occlusion in ten nonvitrectomized and five vitrectomized eyes. Branch retinal vein occlusion caused a significant decrease in preretinal oxygen tension in nonvitrectomized eyes, in which the oxygen tension fell from 20 +/- 7 to 6 +/- 5 mmHg (P = 0.001). Conversely, in vitrectomized eyes the oxygen tension was not significantly reduced after branch retinal vein occlusion. The data demonstrate that branch retinal vein occlusion causes retinal hypoxia in nonvitrectomized eyes, whereas after vitrectomy the hypoxic effect of branch retinal vein occlusion is reduced. The relief of retinal hypoxia that follows vitrectomy may be responsible for halting retinal neovascularization after vitrectomy in diabetic patients.     

Intravitreal triamcinolone acetonide for treatment of central retinal vein occlusion

PURPOSE: To evaluate the effect of intravitreal triamcinolone acetonide on visual acuity and intraocular pressure in patients with central retinal vein occlusion. METHODS: This prospective comparative non-randomized clinical interventional study included 32 patients (33 eyes) with central retinal vein occlusion. The study group (12 patients; 13 eyes) received an intravitreal injection of about 20 mg of triamcinolone acetonide. The control group (20 patients) did not receive any treatment. Mean follow-up was 10.1+/-8.6 months in the study group and 6.0+/-5.2 months in the control group. RESULTS: In the study group, mean visual acuity increased significantly (p=0.018) from 0.11+/-0.11 preoperatively to a best visual acuity during follow-up of 0.18+/-0.15. An improvement in visual acuity by at least 2 Snellen lines and 3 Snellen lines, respectively, was found for 8 (62%) eyes and 5 (38) eyes. Visual acuity measurements determined 1 month (p=0.038) and 3 months (p=0.046) after the injection were significantly higher than the baseline values. Increase in visual acuity was higher in the non-ischemic subgroup than in the ischemic subgroup. In the control group, baseline visual acuity and best visual acuity during the followup did not vary significantly (p=0.33). Visual acuity decreased significantly (p=0.007) towards the end of the follow-up. Comparing study group and control group, gain in visual acuity was significantly (p=0.01) higher in the study group. In the study group, intraocular pressure increased significantly (p=0.018) from 14.4+/-3.9 mmHg to a mean maximal value of 21.6+/-9.2 mmHg (range, 10-44 mmHg), and re-decreased (p=0.012) towards the end of follow-up to 15.3+/-5.1 mmHg (range, 10-21 mmHg). CONCLUSIONS: Intravitreal triamcinolone acetonide temporarily increases visual acuity in central retinal vein occlusion. It is accompanied by an increase in intraocular pressure.     

Branch retinal vein occlusion treated by intravitreal triamcinolone acetonide

PURPOSE: To evaluate the effect of intravitreal triamcinolone acetonide on visual acuity in branch retinal vein occlusion. METHODS: The prospective comparative nonrandomized clinical interventional study included 28 patients (28 eyes) with branch retinal vein occlusion. The study group consisting of 10 consecutive patients received an intravitreal injection of 20-25 mg of triamcinolone acetonide. The control group including 18 patients did not receive an intravitreal injection. The mean follow-up was 8.7+/-4.4 months. RESULTS: In the study group, mean visual acuity increased significantly (P=0.02) from 0.27+/-0.11 preoperatively to a best postoperative visual acuity of 0.45+/-0.27. Visual acuity measurements determined 1 month after the injection were significantly (P=0.027) higher than baseline values. Nine (90%) eyes gained in visual acuity, with six (60%) eyes showing an increase in visual acuity of at least two Snellen lines. In the ischaemic subgroup, visual acuity did not change significantly (0.18+/-0.18 to 0.13+/-0.04; P=0.66), while, in the nonischaemic subgroup, visual acuity increased significantly (P=0.012) from the baseline value to the best postoperative measurement (0.29+/-0.09 to 0.53+/-0.24). In the control group, baseline visual acuity and best visual acuity during the follow-up did not vary significantly (P=0.27). Comparing the study and control groups with each other, the gain in visual acuity was significantly higher in the study group at 1 month (P=0.016) and 2 months (P=0.012) after baseline. CONCLUSIONS: Intravitreal injection of triamcinolone acetonide can increase visual acuity in patients with branch retinal vein occlusion.     

Ophthalmodynamometry and corticosteroids in central retinal vein occlusion

Purpose : This is the first report of the monitoring of the clinical progress of a central retinal vein occlusion by measuring the retinal venous collapse pressure using ophthalmodynamometry.
Method : A 38-year-old woman with a non-ischaemic central retinal vein occlusion received systemic prednisone. The dose of prednisone was increased and decreased both abruptly and gradually. The response was monitored by weekly measurements of visual acuity, retinal appearance and retinal venous collapse pressure. The retinal appearance was assessed by comparison of repeated stereo colour photographs and fluorescein angiographs. Retinal venous collapse pressure was estimated by taking the mean of four or more ophthalmodynamometric measurements.
Results : An inverse relationship between the ophthalmodynamometric retinal venous collapse pressure and systemic prednisone dosage was observed. The visual acuity and retinal appearance remained unchanged throughout the follow-up.
Conclusions : Ophthalmodynamometry in this case was a useful method of quantitatively monitoring the response of central retinal vein occlusion to systemic prednisone. The response would not have been detected if only visual acuity and retinal appearance were used to monitor the progress.     

The pulsation and the pressure of the central retinal vein and their relation to glaucoma damage and therapy

Until now the pressure in the intraocular veins was generally equated with the intraocular pressure. According to recently available knowledge the pressure in the central retinal vein may be considerably higher than the intraocular pressure. Therefore, the pressure in the veins of the prelaminar layer of the optic nerve head may be higher than the intraocular pressure also. In this case the perfusion pressure equals the difference: arterial pressure minus central retinal venous pressure. It has been shown that the central retinal venous pressure is higher in glaucoma patients than in healthy subjects and it is higher in the eyes with the larger excavation in patients with unequal excavations. The central retinal venous pressure is a considerable risk factor for the progression of glaucoma damage. It seems to be appropriate to judge the pulsation of the central retinal vein in glaucoma patients, assessing the risk of glaucoma damage, and to measure the pressure in the central retinal vein by contact lens dynamometry. It may be concluded that a solely pressure-lowering therapy is ineffective in eyes in which the pressure of the central retinal vein is higher than the intraocular pressure. That may apply to about 40-50% of glaucoma patients.     

Systemic diseases associated with various types of retinal vein occlusion

PURPOSE: To investigate systemic diseases associated with various types of retinal vein occlusion. METHODS: We investigated prospectively in 1090 consecutive patients with retinal vein occlusion, almost all Caucasian (consistent with the racial pattern here), the prevalence of associated systemic disorders before or at the onset of various types of retinal vein occlusion. The patients were categorized into six types of retinal vein occlusion based on defined criteria: nonischemic and ischemic central retinal vein occlusion, nonischemic and ischemic hemi-central retinal vein occlusion, and major and macular branch retinal vein occlusion. The patients had a detailed ophthalmic and systemic evaluation according to our protocol. For data analysis, patients were divided into three age groups: young (younger than 45 years), middle-aged (45 to 64 years), and elderly (65 years or older). The observed prevalence rates of major systemic diseases were compared among central retinal vein occlusion, hemi-central retinal vein occlusion, and branch retinal vein occlusion using a polytomous logistic regression analysis adjusting for gender and age. Logistic regression adjusting for age and gender was also used to compare the observed prevalence of systemic disease between nonischemic and ischemic in central retinal vein occlusion and hemi-central retinal vein occlusion and between major and macular branch retinal vein occlusion. These observed prevalence rates were also compared with those expected in a gender-matched and age-matched control population from estimates from the US National Center for Health Statistics. RESULTS: There was a significantly higher prevalence of arterial hypertension in branch retinal vein occlusion compared with central retinal vein occlusion (P < .0001) and hemi-central retinal vein occlusion (P = .028). Branch retinal vein occlusion also had a significantly higher prevalence of peripheral vascular disease (P = .0002), venous disease (P = .011), peptic ulcer (P = .031), and other gastrointestinal disease (P < .0001) compared with central retinal vein occlusion. The proportion of patients with branch retinal vein occlusion with cerebrovascular disease was also significantly (P = .049) greater than that of the combined group of patients with central retinal vein occlusion and patients with hemi-central retinal vein occlusion. There was no significant difference in prevalence of any systemic disease between central retinal vein occlusion and hemi-central retinal vein occlusion. A significantly greater prevalence of arterial hypertension (P = .025) and diabetes mellitus (P = .011) was present in the ischemic central retinal vein occlusion compared with the nonischemic central retinal vein occlusion. Similarly, arterial hypertension (P = .0002) and ischemic heart disease (P = .048) were more prevalent in major branch retinal vein occlusion than in macular branch retinal vein occlusion. Relative to the US white control population, the combined group of patients with central retinal vein occlusion and patients with hemi-central retinal vein occlusion had a higher prevalence of arterial hypertension (P < .0001), peptic ulcer (P < .0001), diabetes mellitus (in ischemic type only, P < .0001), and thyroid disorder (P < .0001). The patients with branch retinal vein occlusion showed a greater prevalence of arterial hypertension (P < or = .005), cerebrovascular disease (P = .007), chronic obstructive pulmonary disease (P = .012), peptic ulcer (P < .0001), diabetes (in young only, P = .0005), and thyroid disorder (P = .003) compared with the US white control population. CONCLUSIONS: The findings of our study revealed that a variety of systemic disorders may be present in association with different types of retinal vein occlusion and in different age groups, and that their relative prevalence differs significantly, so that the common practice of generalizing about these disorders for the entire group of patients with retinal vein occlusion can be misleading. The presence of a particular associated systemic disease does not necessarily imply a cause-and-effect relationship with that type of retinal vein occlusion; the particular disease may or may not be one of the risk factors in a multifactorial scenario predisposing an eye to develop a particular type of retinal vein occlusion. Based on our study, we think that apart from a routine medical evaluation, an extensive and expensive workup for systemic diseases is unwarranted in the vast majority of patients with retinal vein occlusion.     

Perimetric sensitivity and retinal thickness in eyes with macular edema resulting from branch retinal vein occlusion

PURPOSE: To document and study the relationship between perimetric sensitivity and retinal thickness at the foveal and parafoveal points in eyes with macular edema associated with branch retinal vein occlusion. METHODS: A prospective study was performed using the central 10-2 Humphrey perimetry program and optical coherence tomography. Seventeen eyes with branch retinal vein occlusion were eligible showing macular edema without macular nonperfusion or massive retinal hemorrhage. RESULTS: The sensitivity and retinal thickness were significantly correlated at the fovea (r = -0.629, P =.006) as well as 1 (r = -0.656, P <.0001) and 3 (r = -0.885, P <.0001) degrees apart from the fovea. The visual acuity that is expressed as a logarithm of the minimum angle of resolution (LogMAR) also correlated with retinal thickness (r = 0.591, P =.011). CONCLUSION: The increased retinal thickness resulting from macular edema is closely correlated with retinal sensitivity as measured by automated static perimetry both at the fovea and parafovea. Measuring the retinal thickness using optical coherence tomography may be useful in monitoring macular edema in eyes with branch retinal vein occlusion.     

Radial optic neurotomy (RON) for central retinal vein occlusion

BACKGROUND: Compression in the lamina cribrosa is discussed as a reason for central retinal vein occlusion. Radial optic neurotomy should release the pressure and increase venous blood outflow. PATIENTS AND METHODS: In a clinical trial 27 eyes with central retinal vein occlusion (22 eyes with clinical ischaemia, 5 eyes with continuous disc oedema and visual acuity below 4/10) underwent surgical decompression by vitrectomy and radial optic neurotomy. During surgery the intravenous pressure in the central vein was tested by infusion dynamometry before and right next to the incision. Follow up-time minimally was 1.5 years. RESULTS: Infusion dynamometry demonstrated a decrease of the central vein pressure right next to the incision in all eyes. In 17/22 eyes with ischaemic type of occlusion 6 weeks after surgery the relative afferent pupillary defect was lowered significantly and no growth of neovascularisations occurred. 5 eyes with persistence of the afferent pupillary defect received laser/cryocoagulation because of neovascularisations. After surgery visual acuity improved in 20/27 eyes and remained unchanged in 4/27 eyes. As complications we saw small subretinal haemorrhages at the neurotomy site (5/27), vitreous haemorrhages (7/27), hypotonia and choroidal detachment (1/27) and segmental visual field loss (14/27). CONCLUSIONS: The results of infusion dynamometry strongly support the hypothesis of a postulated compression of the central retinal vein in the lamina cribrosa. Functional results of radial optic neurotomy are superior to those of the natural course of ischaemic retinal vein occlusion in the literature, but visual field defects in association with the neurotomy site seem to be a serious side-effect of this therapeutic approach.     

Anatomy of arteriovenous crossings in branch retinal vein occlusion

We studied the photographic records of 292 eyes, including 103 eyes with branch retinal vein occlusion, 90 fellow eyes, and 99 control eyes without branch retinal vein occlusion. All arteriovenous crossings within three disk diameters of the optic disk, including the crossings at the sites of branch retinal vein occlusions, were studied. The relative positions of the crossing artery and vein could be determined at 1,939 crossings in all eyes. Crossings at which a vein crossed over an artery were a common finding (22.3% to 33.0% of crossings), but were rare at the crossings where branch retinal vein occlusions were found (2.4%). A greater proportion of arterial overcrossings was found in eyes with branch retinal vein occlusions (77.7%) compared to fellow eyes (70.6%) or control eyes (67.0%). Our data indicate that arterial overcrossings are at relatively higher risk of branch retinal vein occlusion than venous overcrossings, and that the risk of branch vein occlusion in an eye is proportional to the number of arterial overcrossings in the eye.     

Central retinal vein occlusion in pseudoexfoliation of the lens capsule

In surveying an extensive group of patients with unilateral pseudoexfoliation of the lens capsule certain interesting points emerged, particularly on the incidence of central retinal vein occlusion in this condition,and perhaps in glaucoma also. A total of 284 patients with unilateral pseudo-exfoliation of the lens capsule were examined clinically after an ophthalmic and general history were taken. Mean intraocular pressure (IOP) was 30.9 mmHg in the affected eye and 18.1 mmHg in the unaffected eye. Central retinal vein occlusion occurred in 10 affected eyes but no unaffected eyes and always in affected eyes with a rise in IOP. Average IOP in the affected eye with central retinal vein occlusion was 37.5 mmHg (range 26-54 mmHg);in the unaffected fellow eye it was 18.0 mmHg (range 11-28 mmHg). Although the process involved in producing pseudo-exfoliation of the lens capsule may contribute to the precipitation of central retinal vein occlusion, these findings suggest the rise in IOP is the more important cause. This may also be so in other forms of glaucoma.     

Assessment of the spontaneous pulsations of the central retinal vein in daily ophthalmic practice

The purpose of this study is to assess the frequency of eyes with a spontaneous pulsation of the central retinal vein in the setting of a busy daily ophthalmic practice. The clinical observational case-series study included 690 eyes (345 subjects). The optic disc was ophthalmoscopically assessed using a non-contact ophthalmoscopic lens at the slit lamp. Out of the study population, 526 eyes (76.2%) of 265 (76.8%) subjects showed a detected spontaneous pulsation of the central retinal vein (prevalence rate: 76.2 +/- 1.6% [mean +/- standard error] per eye, and 76.8 +/- 2.3% per subject). In univariate analysis, the presence of a detected spontaneous central retinal vein pulsations was statistically associated with systolic systemic blood pressure (P = 0.04) and with the ocular perfusion pressure (P = 0.03). The results suggest that as examined in the setting of a busy daily ophthalmic practice, the central retinal vein was found to show a spontaneous pulsation in about 80% of the subjects.     

Vitrectomy for macular edema combined with retinal vein occlusion

This study was performed in order to evaluate the effect of vitrectomy in eyes with retinal vein occlusion associated with macular edema. Twenty-nine years eyes (27 patients) with branch retinal vein occlusion (BRVO), and 14 eyes (13 patients) with central retinal vein occlusion (CRVO) both associated with macular edema underwent phacoemulsification, intraocular lens implantation, pars plana vitrectomy and peeling of the posterior hyaloid membrane. Follow-up ranged from 12 to 32 months. Macular edema was reduced, and visual improvement was observed (p < 0.0001 in BRVO, p = 0.0257 in CRVO, paired t-test). Visual outcome was better in eyes with better visual acuity before surgery. Early vitrectomy may be recommended for retinal vein occlusion associated with macular edema. This revised version was published online in July 2006 with corrections to the Cover Date.     

Induction of retinochoroidal venous anastomosis in central retinal vein occlusion with macular edema via a full-thickness retinochoroidal incision

PURPOSE: To report the induction of retinochoroidal venous anastomosis (RCVA) in the treatment of nonischemic central retinal vein occlusion (CRVO) with macular edema via a full-thickness retinochoroidal incision. METHODS: In nine eyes with nonischemic CRVO and intractable macular edema, one or two full-thickness incisions transacting a major retinal branch vein to the level of inner sclera were made in conjunction with vitrectomy. Fluorescein angiography was conducted to evaluate the formation of functional RCVA. Best-corrected visual acuity (BCVA) and central macular thickness (CMT) were compared before and after the surgery. RESULTS: The mean follow-up period +/- SD was 12.0 +/- 5.1 months. All nine eyes developed functional RCVA after the surgery. The mean BCVA +/- SD improved from 0.75 +/- 0.30 logMAR (logarithm of the minimal angle of resolution) to 0.55 +/- 0.26 logMAR (P = 0.018), and the mean CMT +/- SD was reduced from 686 +/- 265 microm to 251 +/- 150 microm (P = 0.011). Additional surgery was performed on one eye due to persistent vitreous hemorrhage. CONCLUSION: Full-thickness retinochoroidal incision appears to raise the rate of successful RCVA formation and may improve the outcome of CRVO with macular edema.