Quantitative MRI of the Prostate and Uterus in Monkeys

Abstract

Quantitative MRI has been carried out in the prostate, seminal vesicles, uterus, and ovaries in the pig-tailed monkey, Macaca nemestrina. T2-weighted, fat-suppressed, multislice experiments were performed at 2.35 T. Eight males, 14 ovariectomized females, and 20 intact females were studied. In the prostate, the caudal and cranial lobe were readily distinguished since the latter had a longer T2 value. For all tissues and organs, interanimal variations were large (up to 12-fold variation in volume), but reproducibility was excellent in the prostate and in the ovariectomized monkey uterus with coefficients of variation (CV) of 3 and 5%, respectively. In the intact monkey uterus, cycle-cycle reproducibility was good with CVs of 6-10% in the myometrium and 14-18% in the endometrium. In the follicular phase, endometrial growth (+3.8% day-1, P < 0.001) was accompanied by myometrial shrinkage (-1.6% day-1, P < 0.001), while in the luteal phase, growth was seen in both tissues (+4.3% day-1, P < 0.001 and +1.4% day-1, P < 0.001, respectively). The great value of these MRI techniques in obtaining data in pharmacological efficacy studies of endocrine drugs, and in limiting the number of animals used, is discussed.

Defining endometrial growth during the menstrual cycle with three‐dimensional ultrasound

“…ENDOMETRIAL GROWTH DURING THE MENSTRUAL CYCLE 947 luteal phase. 19,20,30 Of the magnetic resonance studies undertaken in the human there is a discrepancy in the description of endometrial growth, some concurring with our findings 21 and others describing continued development that peaks in the luteal phase. 22,33 Comparison with these studies, however, is often compounded because they invariably involve fewer time points and report mean measurements during the follicular phase against those in the luteal phase.…”

“…The majority of information reflects volume estimates from three‐dimensional data derived from magnetic resonance imaging. Animal models show continued endometrial growth throughout the cycle accompanied by myometrial shrinkage during the follicular phase, which recovers in the luteal phase 19,20,30 . Of the magnetic resonance studies undertaken in the human there is a discrepancy in the description of endometrial growth, some concurring with our findings 21 and others describing continued development that peaks in the luteal phase 22,33 .…”

“…The majority of information defining changes in endometrial volume during the menstrual cycle is derived from magnetic resonance imaging 19–22 . Only one group has used three‐dimensional ultrasound to describe these changes and this involved women attending the gynaecology clinic 23 .…”

Prostate-Sparing Effects in Primates of the Potent Androgen 7α-Methyl-19-Nortestosterone: A Potential Alternative to Testosterone for Androgen Replacement and Male Contraception1

“…MRI proved to be a precise modality for measuring prostate size in monkeys, confirming the one prior report on this topic (40). This pilot study was performed to assure that the duration of planned steroid infusions was adequate to assess responses in the above parameters as well as to confirm that prostate volumes could be assessed using MRI.…”

Stimulation and inhibition of bone formation: use of peripheral quantitative computed tomography in the mouse in vivo

“…animal experiments addressing disease progression and drug efficacy (Waterton et al 1992, Waterton et a1. 1996,provided that precise and accurate quantitation of the images is achieved.…”