Architecture of the Corpus Spongiosum: An Anatomical Study.

PURPOSE: Urethral reconstruction is performed for urethral stricture or hypospadias correction. Research on urethral tissue engineering is increasing. Because the corpus spongiosum is important to support the urethra, urethral tissue engineering should ideally be combined with reconstruction of a corpus spongiosum. We describe a method to visualize and measure the architecture of the corpus spongiosum, which is needed for scaffold design. MATERIALS AND METHODS: The penis was dissected from 2 unembalmed male cadavers. One penis was flaccid and the other was erect, as induced by saline infusion. Both were frozen in ice. At 6 sites sections were obtained in the transverse and frontal directions. After digitalizing the stained sections the images were edited, area measurements were taken and a 3-dimensional reconstruction was made. RESULTS: In transverse sections the mean area of the vascular lumen was 60% and 77% in the flaccid and the erect corpus spongiosum, and in frontal sections it was 53% and 74%, respectively. This indicated a 129% transverse increase and a 140% longitudinal increase in erection. Section sites did not essentially differ except in the glans penis. Frontal sections showed larger vascular cavities and more incomplete septae than transverse sections. CONCLUSIONS: This study provides what is to our knowledge novel information on corpus spongiosum architecture, which is relevant for scaffold design in tissue engineering. The study protocol can be used in future research with a larger number of specimens and more extensive analyses.

Online formative tests linked to microlectures improving academic achievement.

BACKGROUND: Online formative tests (OFTs) are powerful tools to direct student learning behavior, especially when enriched with specific feedback. AIM: In the present study, we have investigated the effect of OFTs enriched with hyperlinks to microlectures on examination scores. METHODS: OFTs, available one week preceding each midterm and the final exams, could be used voluntarily. The use of OFTs was related to scores on midterm and final exams using ANOVA, with prior academic achievement as a covariate. RESULTS: On average, 74% of all students used the online formative tests (OFT+) while preparing for the summative midterm exam. OFT+ students obtained significantly higher grades compared to OFT-students, both without and with correction for previous academic achievement. Two out of three final exam scores did not significantly improve. CONCLUSION: Students using online formative tests linked to microlectures receive higher grades especially in highly aligned summative tests.