Development of a conjunctival tissue substitute on the basis of plastic compressed collagen.

Ocular surface disorders, such as pterygium, cicatricial pemphigoid and external disruptions, can cause severe inflammation, scarring, fornix shortening as well as ankyloblepharon. Current treatments do not resolve these conditions sufficiently. The aim of this study was to evaluate clinical applicability and suitability of plastic compressed collagen to serve as a substrate for the expansion of human conjunctival epithelial cells in order to develop an epithelialized conjunctival substitute for fornix reconstruction. Human conjunctival epithelial cells were expanded on plastic compressed collagen gels. Epithelial cell characteristics were evaluated by haematoxylin and eosin staining, electron microscopy and cytokeratin expression. The expression of putative epithelial progenitor cell markers p63α, ABCG2 and CK15 was assessed by immunostaining. The proliferative capacity and clonal growth of the cells was evaluated before (P0) and after expansion (P1) on the plastic compressed collagen gels by colony forming efficiency assay. The potential clinical applicability of this gel substitutes was evaluated by assessment of their biomechanical properties as well as their surgical handling. Human conjunctival epithelial cells cultured on plastic and plastic compressed collagen gels formed a confluent cell layer and expressed CK19. The cells showed expression of the putative epithelial progenitor cell markers p63α, ABCG2 and CK15 and sustained colony forming ability. The compressed collagen gels showed a high ultimate tensile strength and elasticity and the surgical handling of gels was comparable to amniotic membrane. An epithelialized conjunctival tissue construct on the basis of compressed collagen might therefore be a promising alternative bioartificial tissue substitute for conjunctival reconstruction. Copyright © 2015 John Wiley & Sons, Ltd.

Limitations of the evaluation of adnexal masses by its macroscopic aspects, cytology and biopsy.

To investigate the relevance of intraoperative macroscopic evaluation of adnexal masses a prospective study was conducted from June 1st, 1993 to May 31st, 1994, which included 57 premenopausal and 60 postmenopausal women, who underwent laparotomy because of a cystic adnexal mass. The surgeons were asked to classify the tumor intraoperatively as benign or malignant and to assign to histologic groups. In addition cytology of the cyst fluid and a biopsy from the cystic wall were evaluated. Comparison of these items with the results of permanent section diagnosis revealed the tendency of the surgeons to underestimate adnexal masses depending on patients' age and the complexity of the tumor, despite of the knowledge of preoperative ultrasonographic findings. Sufficient cytolologic examination was possible in only one third of aspirates and only 21% of the examined postmenopausal malignant neoplasms have correctly been diagnosed by cytology. Evaluation of the biopsy specimens demonstrates a marked percentage of false negatives with respect to benign tumors (30% of non-functional benign neoplasms in the premenopause were assessed as functional cysts) as well as malignant neoplasms (only 72% were diagnosed correctly in the postmenopause group). In conclusion intraoperative subjective assessment, cytology and representative biopsies do not necessarily concur with the definitive histological diagnosis.