Mansour Ashoor1, Abdollah Khorshidi2, Leila Sarkhosh1. 1. Nuclear Science & Technology Research Institute, P.O. Box: 113653486, Tehran, Iran. 2. Cellular and Molecular Research Center, Gerash University of Medical Sciences, P.O. Box: 7441758666, Gerash, Iran.
Abstract
AIM: One of the most important microvasculatures' geometrical variables is number of pores per capillary length that can be evaluated using MRI. The transportation of blood from inner to outer parts of the capillary is studied by the pores and the relationship among capillary wall thickness, size and the number of pores is examined. BACKGROUND: Characterization of capillary space may obtain much valuable information on the performance of tissues as well as the angiogenesis. METHODS: To estimate the number of pores, a new pseudo-liquid drop model along with appropriate quantitative physiological purposes has been investigated toward indicating a package of data on the capillary space. This model has utilized the MRI perfusion, diffusion and relaxivity parameters such as cerebral blood volume (CBV), apparent diffusion coefficient (ADC), ΔR 2 and Δ R 2 * values. To verify the model, a special protocol was designed and tested on various regions of eight male Wistar rats. RESULTS: The maximum number of pores per capillary length in the various conditions such as recovery, core, normal-recovery, and normal-core were found to be 183 ± 146, 176 ± 160, 275 ± 166, and 283 ± 143, respectively. This ratio in the normal regions was more than that of the damaged ones. The number of pores increased with increasing mean radius of the capillary and decreasing the thickness of the wall in the capillary space. CONCLUSION: Determination of the number of capillary pore may most likely help to evaluate angiogenesis in the tissues and treatment planning of abnormal ones.
AIM: One of the most important microvasculatures' geometrical variables is number of pores per capillary length that can be evaluated using MRI. The transportation of blood from inner to outer parts of the capillary is studied by the pores and the relationship among capillary wall thickness, size and the number of pores is examined. BACKGROUND: Characterization of capillary space may obtain much valuable information on the performance of tissues as well as the angiogenesis. METHODS: To estimate the number of pores, a new pseudo-liquid drop model along with appropriate quantitative physiological purposes has been investigated toward indicating a package of data on the capillary space. This model has utilized the MRI perfusion, diffusion and relaxivity parameters such as cerebral blood volume (CBV), apparent diffusion coefficient (ADC), ΔR 2 and Δ R 2 * values. To verify the model, a special protocol was designed and tested on various regions of eight male Wistar rats. RESULTS: The maximum number of pores per capillary length in the various conditions such as recovery, core, normal-recovery, and normal-core were found to be 183 ± 146, 176 ± 160, 275 ± 166, and 283 ± 143, respectively. This ratio in the normal regions was more than that of the damaged ones. The number of pores increased with increasing mean radius of the capillary and decreasing the thickness of the wall in the capillary space. CONCLUSION: Determination of the number of capillary pore may most likely help to evaluate angiogenesis in the tissues and treatment planning of abnormal ones.
Entities:
Keywords:
2DFT, two-dimensional Fourier transform; ADC, apparent diffusion coefficient; CBF, cerebral blood flow; CBV, cerebral blood volume; DWI, diffusion weighted imaging; Diameter; Diffusion MRI; FLASH, fast low angle shot; FOV, field of view; MCA, middle cerebral artery; MTT, mean transit time; Microvasculature; PWI, perfusion weighted imaging; Pores; Pseudo-liquid drop model; RF, radio frequency; ROI, region of interest; TCL, total capillary length; VSI, vessel size index; Wistar rats
Authors: Michal E Komlosh; Evren Özarslan; Martin J Lizak; Ferenc Horkay; Vincent Schram; Noam Shemesh; Yoram Cohen; Peter J Basser Journal: J Magn Reson Date: 2010-10-26 Impact factor: 2.229