Complications by modified<i>C</i>lavien classification.

*<p>Some cases experienced one or more complications.</p

Operative characteristics.

<p>Operative characteristics.</p

Demographic and clinical preoperative characteristics.

<p>Demographic and clinical preoperative characteristics.</p

Comparison of two cannulation methods for assessment of intracavernosal pressure in a rat model

<div><p>Intracavernous pressure (ICP) measurement is a well-established technique for assessing the erectile function, which was performed by cannulating either crus or shaft of the penis. However, there are no studies concerning the experimental performance of the two cannulation sites yet. The aim of this study was to compare the measuring outcomes using two different cannulation sites. To validate the capacity of our study, both normal and the castration-induced erectile dysfunction rat models were conducted. Fifty adult male Sprague-Dawley rats were randomized equally into two groups: an intact group and a castration group. Five rats from each group firstly underwent different stimulation parameters to detect the optimal erectile responses. The residual rats in each group were further assigned into two subgroups (n = 10 per subgroup) according to two different cannulation sites (crus or shaft of the corpus cavernosum). The ICP values were compared between groups after different interventions. The optimal parameters for mean maximum ICP were recorded at 2.5V and a frequency of 15 Hz. The rats under the two different cannulation sites tended to show similar ICP values in both the intact and the castration groups. However, the success rate in monitoring ICP was significantly higher in the groups cannulating into the shaft of the penis compared to the crus (100% <i>vs</i>. 70%; <i>P</i> = 0.02). Our data suggested that the method of cannulation into the penile shaft could serve as a better alternative for the ICP measurement in rats.</p></div

Changes of ICP, MAP, ICP/MAP and the area under the curve (AUC) of each group.

<p>(A-D): Biopac physiograph displayed the ICP (left) and MAP (right) of representative rats in Group A-D. The x-axis depicted seconds and the horizontal bar represented one electrical stimulus lasting 60 seconds. The Y-axis represented changes in ICP or MAP. (E, F): Statistical chart of ICP/MAP ratio and total AUC in each group (n = 8, 10, 6, 10, respectively). Bar graphs represent means±SD, ^#<i>P</i> <0.01. Group A = intact rats under the method of cannulation into the crus of the penis; Group B = intact rats cannulating into the penile shaft; Group C = castrated rats with penile crus cannulation; Group D = castrated rats with penile shaft cannulation.</p

Effect of different voltages and frequencies on the erectile function parameters.

<p>(A, B): Quantitative analyses of erectile function at different voltages (1–10 V) of electrical stimulation induced in ICP in the intact group (left) and the castration group (right). (C, D): Representative ICP changes at different frequencies (10, 15 and 20 Hz) in the intact group (left) and the castration group (right). The x-axis depicted seconds and the Y-axis represented changes in ICP, black bars under the x-axis indicated a 60-second period of stimulation. (E, F) Quantitative analyses of mean maximum ICP at different frequencies (10, 15 and 20 Hz) in the intact group (left) and the castration group (right). These results were compiled from 5 of 25 animals in each of the intact group and the castration group. Each bar depicts the mean ± SEM, ^#<i>P</i> < 0.01.</p

Macroscopic images show different cannulation site in the corpus cavernosum.

<p>(A) Cannulating into the crus of the penis. (B) Cannulating into the penile shaft. (C) Anatomic relationships between the crus of the penis, the urethra, and the corpus spongiosum.</p

Exposure of the major pelvic ganglion (MPG) and the cavernosal nerve (CN).

<p>(A) The MPG can be found next to the internal iliac vein. (B) The exposed MPG and the CN. (C) The CN was isolated using a glass needle.</p

Mean arterial pressure (MAP) and intracavernous pressure (ICP) measurement.

<p>(A) The right internal carotid artery was detached and intubated with a 24-gauge angiocatheter to measure MAP. (B) Pulse stimulator was connected to a stainless steel bipolar hook electrode positioned on the cavernous nerves (CN). The parallel hooks were kept apart by an insulator. A piece of a latex glove was used to isolate the distal ends of the electrical stimulators. ICP was recorded with a 24-gauge venoclysis needle inserted into the corpora cavernosum and connected to a pressure transducer.</p

ICP and MAP indexes of rats in each experimental group.

<p>ICP and MAP indexes of rats in each experimental group.</p