The effect of moderate treadmill exercise on the resistive index of the medial long posterior ciliary artery in dogs

The resistive index (RI) is an indirect measurement of arterial resistance by means of a ratio between the peak systolic and end diastolic velocities recorded with a spectral Doppler device, especially used to evaluate the vascular damage in ocular diseases such as glaucoma. Some ocular variables such as the intraocular pressure (IOP), the choroidal thickness, the axial length and the ocular blood flow may be influenced by physical exercise. The purpose of this study was to evaluate the influence of the exercise on the RI of the medial long posterior ciliary artery in dogs, and correlate the data obtained with the IOP values. Ten clinically healthy dogs were subjected to moderate physical exercise on a canine motorised treadmill at different speeds for 45 minutes. A colour Doppler examination was performed and the RI values were calculated for the medial long posterior ciliary artery at rest, immediately after the exercise, and after 60 minutes at the end of the exercise. At the same times, the IOP was recorded by applanation tonometry. The data were analysed by a two-way repeated ANOVA measurement in order to compare the RI and the IOP. Wilcoxon’s test was applied for the post hoc comparison. Spearman’s rank correlation for non-normal distribution was used to determine a relationship between the RI and the IOP. The at rest RI was 0.722 +/–0.022, IOP 12.38 +/3.21 mm Hg. A significant decrease in the RI was observed immediately after the exercise (0.697 +/–0.035) and during the passive recovery phase (0.682 +/–0.042). A significant decrease in the IOP (11+/3.39 mmHg) was recorded after 60 min of the passive recovery phase; at the end of the exercise, a slight decrease (12.29+/4.26 mm Hg) mm Hg was detected. During the test, a linear correlation between the RI and the IOP was observed. Our results suggest that exercise induces the modification of the ophthalmic blood flow in dogs, presumably related to the compensatory neuro-hormonal mechanisms.

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Effects of anti-glaucoma drugs on resistive index of the medial long posterior ciliary artery using color Doppler imaging in Beagle dogs

Journal of Veterinary Science ◽

10.4142/jvs.2011.12.1.99 ◽

2011 ◽

Vol 12 (1) ◽

pp. 99 ◽

Cited By ~ 3

Author(s):

Hojung Choi ◽

Youngwon Lee ◽

Seongchan Yeon ◽

Hyojong Lee ◽

Heechun Lee

Keyword(s):

Color Doppler ◽

Resistive Index ◽

Color Doppler Imaging ◽

Doppler Imaging ◽

Beagle Dogs ◽

Posterior Ciliary Artery ◽

Ciliary Artery

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Determination of the effect of a single hemodialysis session on retrobulbar blood hemodynamics by color Doppler ultrasonography

Acta Radiologica ◽

10.1080/02841850701348713 ◽

2007 ◽

Vol 48 (7) ◽

pp. 763-767 ◽

Cited By ~ 12

Author(s):

Ö. Tosun ◽

B. Davutluoglu ◽

K. Arda ◽

M. Boran ◽

A. Yarangumeli ◽

...

Keyword(s):

Blood Flow ◽

Doppler Ultrasonography ◽

Color Doppler ◽

Color Doppler Ultrasonography ◽

Rank Test ◽

Posterior Ciliary Artery ◽

Hemodialysis Session ◽

Paired Samples ◽

Before And After ◽

Ciliary Artery

Background: Retrobulbar hemodynamic alterations can occur during hemodialysis sessions, and patients with chronic renal failure may experience visual problems. Purpose: To evaluate the effect of single-session hemodialysis on retrobulbar vessel hemodynamics by color Doppler ultrasonography. Material and Methods: Thirty-five patients were included in the study. Retrobulbar blood flows were examined before and after dialysis sessions. Doppler spectral patterns of retrobulbar blood flow were evaluated. The t test for paired samples and the Wilcoxon matched-pairs signed-rank test were used for comparing the flow values before and after dialysis. Results: Systolic and diastolic blood flow velocities of the ophthalmic artery, central retinal artery, central retinal vein, nasal posterior ciliary artery, and temporal posterior ciliary artery were found to be decreased bilaterally after hemodialysis sessions. No significant change was observed in resistivity index values after hemodialysis sessions. Conclusion: Our findings reveal that retrobulbar circulation was disturbed after a single hemodialysis session.

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Associating the biomarkers of ocular blood flow with lamina cribrosa parameters in normotensive glaucoma suspects. Comparison to glaucoma patients and healthy controls

PLoS ONE ◽

10.1371/journal.pone.0248851 ◽

2021 ◽

Vol 16 (3) ◽

pp. e0248851

Author(s):

Patrycja Krzyżanowska-Berkowska ◽

Karolina Czajor ◽

D. Robert Iskander

Keyword(s):

Blood Flow ◽

Ophthalmic Artery ◽

Lamina Cribrosa ◽

Ocular Blood Flow ◽

Central Retinal Artery ◽

Healthy Controls ◽

Mean Flow ◽

Posterior Ciliary Artery ◽

Retinal Artery ◽

Ciliary Artery

Purpose To evaluate association between ocular blood flow biomarkers and lamina cribrosa parameters in normotensive glaucoma suspects compared to glaucoma patients and healthy controls. Methods A total of 211 subjects (72 normotensive glaucoma suspects, 70 with primary open-angle glaucoma and 69 controls) were included. Ocular blood flow biomarkers in ophthalmic artery, central retinal artery, as well as in nasal and temporal short posterior ciliary arteries were measured using colour Doppler imaging. Lamina cribrosa position was assessed by measuring its depth, deflection depth, lamina cribrosa shape index and its horizontal equivalent (LCSIH) on B-scan images obtained using optical coherence tomography. Results Ocular blood flow biomarkers in glaucoma patients were statistically significantly reduced when compared to healthy controls in peak systolic velocity (PSV) (P = 0.001 in ophthalmic artery and P<0.001 in central retinal artery) and mean flow velocity (Vm) (P = 0.008 in ophthalmic artery and P = 0.008 in central retinal artery), but not statistically significantly different to that of glaucoma suspects except for PSV in central retinal artery (P = 0.011). Statistically significant correlations corrected for age, central corneal thickness and intraocular pressure were found in glaucoma patients between LCSIH and end diastolic velocity of central retinal artery (P = 0.011), and of nasal short posterior ciliary artery (P = 0.028), and between LCSIH and Vm of central retinal artery (P = 0.011) and of nasal short posterior ciliary artery (P = 0.007). No significant correlations were observed between these parameters in glaucoma suspects and healthy controls. Conclusions Impaired ocular blood flow associated with the deformation of lamina cribrosa was found in glaucoma patients, whereas glaucoma suspects had similar lamina cribrosa shape to glaucoma patients but that deformation was not associated with ocular blood flow biomarkers.

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Paediatric Cerebral Arteriovenous Malformations: Value of Colour Doppler Ultrasound in the Diagnosis and Management of Endovascular Treatment

Rivista di Neuroradiologia ◽

10.1177/197140099701000202 ◽

1997 ◽

Vol 10 (2) ◽

pp. 151-155

Author(s):

M. Rollo ◽

N. Burdi ◽

P. Fiorentino ◽

T. Pasquariello ◽

G.P. Tamburrini

Keyword(s):

Blood Flow ◽

Endovascular Treatment ◽

Arteriovenous Malformations ◽

Resistive Index ◽

Indirect Measurement ◽

Vein Of Galen ◽

Colour Doppler ◽

Non Invasive ◽

Doppler Us ◽

Haemodynamic Changes

Colour Doppler ultrasound is a new diagnostic method in neuroradiology allowing the non invasive imaging of parenchymal and vascular structures in adults as in children through the intact skull. In particular, this study describes the use of colour Doppler US in children with intracranial arteriovenous malformations to determine its value in the evaluation of haemodynamic changes in cerebral vessels. To test the hypothesis that colour Doppler US analysis of spectral waveforms can be considered an indirect measurement of volume flow in major arteries and veins, we performed 13 colour Doppler US examinations on 4 children with vein of Galen malformations, 2 with parenchymal arteriovenous malformations and 7 children with facial angiomas, before the endovascular treatment, immediately thereafter and after a short time. Peak systolic and end-diastolic flow velocities, resistive index and pulsatility index, quantitative expression of cerebral blood flow, was attempted, while qualitative parameters such as blood flow direction, spectral waveform morphology and spectral broadening were not considered useful in the study. Colour Doppler US performed after endovascular treatment showed: a decrease of main feeder flow velocity and an increased pulsatility index and/or resistive index (as indirect measurement of increased peripheral stream resistance); the presence of echogenic foci within blood vessels, in the nidus or in the vein of Galen, representing embolisation materials or thrombi, such as residual color flow in the same embolised vascular territories; decreased blood flow velocity and spectral broadening in draining veins, indicating an incomplete occlusion of fistulas. In one case of vein of Galen malformation, we performed colour Doppler US three days after the embolisation, showing the occlusion by thrombi of the vein of Galen and of the draining veins. Colour Doppler US can be considered a valuable method for non-invasive haemodynamic assessment of blood flow in cerebral arteriovenous malformations. With this procedure, allowing serial examinations with unlimited repeatability and by using portable equipment at the patient' bedside, it is possible to monitor haemodynamic changes after embolisation. This limits the use of more invasive procedures such as CT, MR and angiography and the relatively large amounts of contrast material and radiation dose.

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Effects of Sympathetic Nerve Stimulation on Long Posterior Ciliary Artery Blood Flow in Cats

Journal of Ocular Pharmacology and Therapeutics ◽

10.1089/108076802317373879 ◽

2002 ◽

Vol 18 (2) ◽

pp. 115-125

Author(s):

Michael C. Koss

Keyword(s):

Blood Flow ◽

Nerve Stimulation ◽

Sympathetic Nerve ◽

Artery Blood Flow ◽

Sympathetic Nerve Stimulation ◽

Posterior Ciliary Artery ◽

Ciliary Artery

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Evaluation of the Effects of Acupuncture on Blood Flow in Humans with Ultrasound Color Doppler Imaging

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2012/513638 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 11

Author(s):

Shin Takayama ◽

Masashi Watanabe ◽

Hiroko Kusuyama ◽

Satoru Nagase ◽

Takashi Seki ◽

...

Keyword(s):

Blood Flow ◽

Vascular Resistance ◽

Color Doppler ◽

Color Doppler Imaging ◽

Doppler Imaging ◽

Posterior Ciliary Artery ◽

Flow Through ◽

Significant Change ◽

Ciliary Artery ◽

Needle Stimulation

Color Doppler imaging (CDI) can be used to noninvasively create images of human blood vessels and quantitatively evaluate blood flow in real-time. The purpose of this study was to assess the effects of acupuncture on the blood flow of the peripheral, mesenteric, and retrobulbar arteries by CDI. Statistical significance was defined asPvalues less than 0.05. Blood flow in the radial and brachial arteries was significantly lower during needle stimulation on LR3 than before in healthy volunteers, but was significantly higher after needle stimulation than before. LR3 stimulation also resulted in a significant decrease in the vascular resistance of the short posterior ciliary artery and no significant change of blood flow through the superior mesenteric artery (SMA) during acupuncture. In contrast, ST36 stimulation resulted in a significant increase in blood flow through the SMA and no significant change in the vascular resistance of the retrobulbar arteries. Additionally, acupuncture at previously determined acupoints in patients with open-angle glaucoma led to a significant reduction in the vascular resistance of the central retinal artery and short posterior ciliary artery. Our results suggest that acupuncture can affect blood flow of the peripheral, mesenteric, and retrobulbar arteries, and CDI can be useful to evaluate hemodynamic changes by acupuncture.

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