Color Doppler imaging of the eye and orbit. A synopsis of a 400 case experience

Multimodality Imaging Assessment of Ocular Ischemic Syndrome

Objectives

To assess the underlying mechanisms of OIS and confirm the haemodynamic and retinal structure changes of early OIS.

Methods

An observational cross-sectional study was conducted of 60 internal carotid artery (ICA) stenosis patients, and they were divided into OIS and control group. Colour doppler imaging, optical coherence tomography, and fundus fluorescein angiography were performed.

Results

The middle cerebral artery (MCA) stenosis differs significantly between the two groups. More OIS patients had new collateral patency of posterior communicating artery (PCoA) and retrograde flow via the ophthalmic artery (OA) (p < 0.001). The peak systolic velocity (PSV) in central retinal artery (CRA) and choroidal thickness (CT) was significantly reduced in OIS patients (p = 0.001 and p < 0.001). The arm-retina time (ART) and the retinal arteriovenous passage time (AVP) were prolonged in OIS patients (p < 0.001 and p = 0.001). CT, ART, and PSV of the CRA showed high sensitivity, while ART and ICA stenosis grade showed high specificity for the diagnosis of OIS according to ROC curve.

Conclusions

Patients who suffered from severe ipsilateral ICA stenosis, new collateral patency of PCoAs, and MCA stenosis may be more susceptible to OIS. The most sensitive sign is PSV of CRA and CT, and the most specific sign is ART.

Can intravitreal ranibizumab alter retrobulbar circulation in eyes with age-related macular degeneration?

PURPOSE

To determine the effect of a single intravitreal ranibizumab injection on retrobulbar circulation in cases with neovascular age-related macular degeneration (AMD).

METHODS

In this prospective and interventional study, 32 patients with neovascular AMD were enrolled. A single intravitreal ranibizumab dose was in only 1 eye per patient. Peak systolic velocity, end-diastolic velocity, resistive index and pulsatility index values in the common carotid artery, ophthalmic artery, central retinal artery, nasal posterior ciliary artery, and temporal posterior ciliary artery in both injected and uninjected healthy fellow eyes were measured using color Doppler ultrasonography at baseline and 1 week and 1 month after the injection of ranibizumab.

RESULTS

All measurements revealed no statistically significant difference among baseline, first week, and first month after injection measurements for all parameters measured in all arteries in both the injected and uninjected healthy fellow eyes.

CONCLUSION

A single intravitreal injection of ranibizumab does not significantly affect on retrobulbar circulation of either the injected or the uninjected healthy fellow eyes with neovascular AMD.

Effect of intravitreal bevacizumab on retrobulbar blood flow in injected and uninjected fellow eyes of patients with neovascular age-related macular degeneration

BACKGROUND

To determine the effect of intravitreal administration of bevacizumab (1.25 mg/0.05 mL) on retrobulbar circulation of the injected and the fellow (uninjected) eyes in patients with neovascular age-related macular degeneration.

METHODS

In this prospective study, the retrobulbar hemodynamics of 43 patients with neovascular age-related macular degeneration was examined by color Doppler ultrasonography. Peak systolic velocity, end-diastolic velocity, and resistive index values in the central retinal artery and short posterior ciliary artery in both injected and uninjected fellow eyes were measured at baseline and 7 days after a single intravitreal injection of bevacizumab.

RESULTS

At baseline, the peak systolic velocity, end-diastolic velocity, and the resistive index in the central retinal artery and short posterior ciliary artery of the injected eye were not significantly different compared with the fellow uninjected eye (P > 0.05 for all). However, intravitreal bevacizumab induced a significant reduction in the peak systolic velocity and end-diastolic velocity and a significant rise in the resistive index of the central retinal artery and short posterior ciliary artery of the injected eye (P ≤ 0.006 for all). Peak systolic velocity and end-diastolic velocity decreased in the central retinal artery (P = 0.023 and P = 0.030) and the short posterior ciliary artery (P = 0.001 and P < 0.000) in the uninjected eye while the resistive index did not significantly change in central retinal artery (P = 0.114) and short posterior ciliary artery (P = 0.082) of the fellow eyes.

CONCLUSION

Intravitreal injection of bevacizumab significantly affects ocular hemodynamic parameters of both the injected and the uninjected fellow eyes with neovascular age-related macular degeneration.

Follow up by colour Doppler imaging of 102 patients with retinal vein occlusion over 1 year

BACKGROUND/AIM

Retinal vein occlusion (RVO) is one of the most frequent ocular vascular diseases and leads to severe vision impairment. Colour Doppler imaging (CDI) is the first method which allows distinct evaluation of arterial and venous velocities in RVO. CDI is valuable for diagnosis of RVO and shows the effects of isovolaemic haemodilution. Patients with RVO were monitored by CDI for 1 year in order to clarify venous and arterial involvement in the pathogenesis of this disease.

METHODS

Patients with RVO were monitored prospectively for 1 year with clinical examinations, fluorescein angiography, and CDI every 3 months. 102 adults referred for RVO for less than 2 months were enrolled. Unaffected eyes were used as control. The maximum systolic and diastolic flow velocities and the resistance index (RI) were measured in the central retinal artery (CRA) and the maximum and minimum blood flow velocities in the central retinal vein (CRV).

RESULTS

During the year of observation, branch retinal vein occlusion (BRVO), ischaemic central retinal vein occlusion (CRVO), and non-ischaemic CRVO had a distinct pattern of venous velocity changes. BRVO had a similar profile to that observed in controls. Venous velocities were continuously lower in central forms, with the lowest values in ischaemic occlusion. In contrast, a brief decrease in arterial diastolic velocity was observed in ischaemic CRVO at presentation, correlated with arteriovenous passage time on fluorescein angiography, but with rapid normalisation.

CONCLUSIONS

CDI findings were correlated with the type of RVO at all times during follow up. CDI showed persistent impairment of central venous velocity in CRVO whereas there was a fast initial values recovery of the arterial velocity. These results using CDI show strong evidence of a primary venous mechanism in RVO.

Orbital color Doppler imaging of optic nerve tumors

OBJECTIVE

To report changes in retinal arterial and venous blood flow pattern in two patients with tumors involving the entire optic nerve.

METHODS

Retrospective review of one patient with clinical and neuroimaging characteristics typical of bilateral optic nerve gliomas and one patient with a probable meningioma of the left optic nerve sheath.

RESULTS

The optic nerve glioma patient had reduced peak systolic velocity of central retinal arteries bilaterally, while the patient with an optic nerve sheath meningioma had relatively low central retinal artery flow velocity and intermittent blood flow in the central retinal vein on the affected side.

CONCLUSIONS

Reduced retinal arterial flow velocities in the setting of optic nerve gliomas may correlate with the presence of optic nerve disease. Phasic blood flow in the central retinal vein with optic nerve sheath meningioma may be the reason that some patients with this tumor develop retinal choroidal venous anastomoses.

Ocular arterial blood flow of choroidal melanoma eyes before and after stereotactic radiotherapy using Leksell gamma knife: 2 year follow up

AIMS

To evaluate the effect of high dose stereotactic radiotherapy on the ocular blood flow of patients with uveal melanoma.

METHODS

Colour Doppler imaging (CDI) was used to measure blood flow velocity and vascular resistance in the ophthalmic, short posterior, and central retinal arteries of nine patients suffering from uveal melanoma. The measurements were taken before, 6 months, 1 year, and 2 years after stereotactic radiotherapy. Irradiation was performed with the Leksell gamma knife with the 59 (41-66.5) Gy total marginal dose divided in two equal fractions. CDI results were compared with age and sex matched healthy control eyes.

RESULTS

At each time of measurement, blood flow velocity in the central retinal artery of the affected eyes was significantly reduced whereas vascular resistance was only increased at the 2 year follow up. Blood flow velocity and vascular resistance in the short posterior arteries of melanoma eyes were also only significantly altered at the 2 year follow up. Blood flow velocity and vascular resistance in the ophthalmic artery of melanoma eyes were not changed at all follow ups.

CONCLUSIONS

In the melanoma eyes, blood flow velocity in the central retinal artery is reduced. High dose stereotactic radiotherapy with the Leksell gamma knife and a 59 (41-66.5) Gy total marginal dose in two fractions leads to a significant reduction of blood flow and a significant increase in resistance variables in the small ocular arteries within 2 years.

Color duplex ultrasonography in the diagnosis of temporal arteritis

BACKGROUND

The diagnosis of temporal arteritis usually requires a biopsy of the temporal artery. We examined the usefulness of color duplex ultrasonography in patients suspected of having temporal arteritis.

METHODS

In this prospective study, all patients seen in the departments of rheumatology and ophthalmology from January 1994 to October 1996 who had clinically suspected active temporal arteritis or polymyalgia rheumatica were examined by duplex ultrasonography. The final diagnoses, made according to standard criteria, were temporal arteritis in 30 patients, 21 with biopsy-confirmed disease; polymyalgia rheumatica in 37; and negative histologic findings and a diagnosis other than temporal arteritis or polymyalgia rheumatica in 15. We also studied 30 control patients matched for age and sex to the patients with arteritis. Two ultrasound studies were performed and read before the biopsies; one ultrasonographer was unaware of the clinical information.

RESULTS

In 22 (73 percent) of the 30 patients with temporal arteritis, ultrasonography showed a dark halo around the lumen of the temporal arteries. The halos disappeared after a mean of 16 days (range, 7 to 56) of treatment with corticosteroids. Twenty-four patients (80 percent) had stenoses or occlusions of temporal-artery segments, and 28 patients (93 percent) had stenoses, occlusions, or a halo. No halos were identified in the 82 patients without temporal arteritis; 6 (7 percent) had stenoses or occlusions. For each of the three types of abnormalities identified by ultrasonography, the interrater agreement was > or =95 percent.

CONCLUSIONS

There are characteristic signs of temporal arteritis that can be visualized by color duplex ultrasonography. The most specific sign is a dark halo, which may be due to edema of the artery wall. In patients with typical clinical signs and a halo on ultrasonography, it may be possible to make a diagnosis of temporal arteritis and begin treatment without performing a temporal-artery biopsy.