Reference Values for Vertebral Artery Flow Volume by Duplex Sonography in Young and Elderly Adults

Abstract

Background and Purpose-Vertebrobasilar ischemia has been attributed to a reduction of net vertebral artery flow volume, the product of mean flow velocity and the cross-sectional area of the vessel. It can be determined by duplex sonography. There are no reference values for vertebral artery flow volume in an age group representative of patients with cerebrovascular disease. Methods-We examined 50 nonvascular neurological patients (age 55.8Ϯ14.0 years). Flow velocities and vessel diameters were recorded in the intertransverse (V2) segments bilaterally, and the flow volume was calculated according to the following equations: (1) Q1ϭtime-averaged mean velocityϫarea and (2) Q2ϭ(time-averaged maximum velocity/2)ϫarea. Results-Flow velocities and vessel diameters tended to be lower on the right side, resulting in a lower flow volume. Flow volumes (according to Equation 1) were 77.2Ϯ29.8 mL/min on the right side, 105.3Ϯ46.4 mL/min on the left side, and 182.0Ϯ56.0 mL/min net. Side-to-side differences were not significant. Flow volumes calculated with the 2 equations did not differ significantly. An age dependence could not be shown, but vessel diameters and net vertebral artery flow volumes were significantly lower in women than in men. The normal range for net vertebral artery flow volume defined by the 5th to 95th percentiles is between 102.4 and 301.0 mL/min. This wide range is due to the high interindividual variability of the parameters. Conclusions-On

Evaluation of Cerebral Blood Flow Volume Using Color Duplex Sonography in Patients With Polycystic Ovary Syndrome

“…Our results for CBF volume were also in substantial agreement with those published previously for young women with CBF volume of 730±87 mL/min (20). Most publications dealing with CBF measurements in healthy adults report a decline in CBF with increasing age, mainly due to a reduction of cortical blood flow while only few authors found that global CBF remains constant during healthy normal aging (20,21) It has been also reported that while ICA flow decreases with age, VA flow shows no change (21,22). In the present study, there was no statistically significant correlation between VA, ICA and CBF volumes with age in both groups.…”

“…All examinations took place in a dimly lighted room with a comfortable temperature (22)(23)(24) 0 C) after an adaptation period for at least 15 minutes rest in supine position. The ICA and vertebral arteries (VA) of both sides were explored with a 7.5-Mhz linear array transducer of a Toshiba Nemio 20 system.…”

Slankstelinių Arterijų Hipoplazija Tarp Jaunų Žmonių

“…Įvairių autorių SA hipoplazijos apibrėžimai skiriasi, t. y. skiriasi spindis, už kurį siauresnė SA vadinama hipoplastiška. Autoriai [2,3,4,5] SA vadina hipoplastiška, jei jos spindis mažesnis negu 2 mm, kiti autoriai [6,7], jei jos spindis mažesnis negu 2,5 mm, o autoriai [8,9], jei jos spindis mažesnis nei 3 mm. Duomenys apie SA hipoplazijos paplitimą populiacijoje svyruoja nuo 2-3 proc.…”

“…Vien SA spindžio išmatavimas gali būti nepakankamas veiksnys vertinant SA hipoplazijos reikšmę kraujotakai, todėl dažnai matuojamas ir pratekančio kraujo tūris, kuris nurodo, kaip sumažėja kraujotaka per SA. Pagal apibrėžimą pratekančio kraujo tūris per SA laikomas sumažėjusiu, jei jis per atitinkamą SA mažesnis negu 40 ml/min, o bendras pratekančio kraujo tūris per abi SA yra mažesnis negu 100 ml/min (matuojama ultragarsinio tyrimo metu) [9].…”

A case of a single intracranial vertebral artery and cerebral infarct

“…The VAs are commonly asymmetric in diameter, with the left most often having a larger diameter than the right [13,15]. Beyond this, the VA is subject to little anatomical variation (estimated to be ~5% of subjects).…”