Vascular damage induced by acute hypertension is preceded by a peculiar pattern where blood vessels show alternating regions of constrictions and dilations ("sausages on a string"). The pattern occurs in the smaller blood vessels, and it plays a central role in causing the vascular damage. A related vascular pattern has been observed in larger vessels from several organs during angiography. In ...

BACKGROUND AND OBJECTIVES Presently, cutaneous vascular lesions are treated using a single cryogen spurt and single laser pulse (SCS-SLP), which do not necessarily produce complete lesion removal in the majority of patients. In this study, the feasibility of applying multiple cryogen spurts intermittently with multiple two-wavelength laser pulses (MCS-MTWLP) was studied using numerical and anim...

BACKGROUND AND OBJECTIVE Simultaneous irradiation and viewing of 10-120 microm cutaneous blood vessels were performed to investigate the effects of 2-micros 577-nm dye laser pulses. STUDY DESIGN/MATERIALS AND METHODS A modified scanning laser confocal microscope recorded vessel response to different radiant exposures (J/cm2). Probit analysis determined the 50% probability ("threshold") radian...

A novel method for the visual and quantitative analysis of the geometrical relationship between the vascular architecture of the brain and white matter pathology is presented. The cerebro vascular system is implicated in the pathogenesis of many diseases of the cerebral white matter, for example, stroke, microcerebrovascular disease, and multiple sclerosis (MS). In our work, white matter lesion...

Despite multiple advances in medical imaging, noninvasive monitoring of therapeutic efficacy for malignant gliomas remains problematic. An underutilized observation is that malignancy induces characteristic abnormalities of vessel shape. These characteristic shape abnormalities affect both capillaries and much larger vessels in the tumor vicinity, involve larger vessels prior to sprout formatio...

Feline pial arteries larger than 100 mu in diameter constricted in response to cervical sympathetic nerve stimulation suggests or in response to topical application of norepinephrine. Smaller pial arteries were unresponsive to norepinephrine. This unresponsiveness persisted when norepinephrine was dissolved in CSF with high calcium ion concentration, or in CSF with both high calcium ion and zer...

BACKGROUND Recent clinical studies have shown that recanalization rates are lower in stent-assisted coil embolization than in coiling alone in the treatment of cerebral aneurysms. OBJECTIVE This study aimed to assess and compare the hemodynamic effect of stent struts and straightening of vessels by stent placement on reducing flow velocity in sidewall aneurysms, with the goal of reducing reca...

The establishment and maintenance of a vascular supply is an absolute requirement for the growth of normal and neoplastic tissues, and as might be predicted, the cardiovascular system is the first organ system to develop and to become functional during embryogenesis. Both during development and in postnatal life, all new blood vessels begin as simple endothelial-lined tubes. Some become capilla...

Our aim was to elucidate the site and mechanism responsible for reactive hyperemia in coronary circulation. In in vivo beating canine hearts, microvessels of the left anterior descending coronary artery (LAD) were observed through a microscope equipped with a floating objective. Flow velocity of the LAD was measured with a suction-type Doppler probe. The LAD was occluded for 20 or 30 seconds an...