Placentabefunde beim Abort: Ein Beitrag zur Patho-Morphologie placentarer Entwicklungsst�rungen

Branching patterns of human placental villous trees: perspectives of topological analysis

Topological analysis was applied to investigate the branching pattern of three specimens obtained from early human placenta (6, 9, and 16 weeks p.m.) reconstructed on the basis of semi-thin sections. Centripetal Horton-Strahler and centrifugal branching order nomenclature was used for topological description of the analysed tree-like structures. Bifurcation ratio and vertex ratio were determined for all three cases and were found to be relatively constant. It was shown that branching pattern is closely related to the model of random segment branching that implicates a high level of asymmetry and a small level of space limitation for branching. The significance of this approach for the analysis of development of the villous tree, for the analysis of mesenchymal villous heterogeneity, and for the estimation of physiological parameters for fetoplacental exchange is discussed. We suggest that topological analysis can lead to a new quantitative classification of branching patterns of the human placental villous trees in normal and pathologic pregnancies.

Surface and branching of placental villi in early abortion: relationship to karyotype. Scanning electron microscopic study

The placental villi of 61 early abortions with known karyotype and 7 legally induced abortions were investigated by scanning electron microscopy and documented in standardised enlargements. Five groups were established from the findings: uniformly branched villi with a velvety surface (group A) were found in 4 of the 7 induced abortions, abundant syncytial sprouts (group B) in 4 of the 6 cases with monosomy X; all 5 cases of triploidy were classified in the group bulbous or spherical villi (group C); 13 out of 25 cases of trisomy were found to have little branching and a surface densely covered with microvilli (group D), while 14 out of the 25 cases of euploidy belonged in the group with slender villi and surface with focal areas of denudation (group E). Forty of the 68 cases were properly assignable to the correct groups (58.8%). The non-uniformity of the villous morphology in the case of induced abortions shows that there is no uniform development of the (early) placenta. The variable morphology seen in abortions with euploidy reflects the various mechanisms of abortion applicable to this group.

A study of placental villi in extrauterine gestation: a guide to the frequency of blighted ova

Material from 329 tubal pregnancies has been examined histologically. In addition, the villous content of glucosaminoglycans was studied. Depending on the degree of the morphological changes three groups can be differentiated: "abortion in association with normal placental findings", "suspicion of blighted ova", and "blighted ova". In the first group (35 cases, 10.64 per cent) there were distinct differences in the morphological picture in contrast to the normal abortion of intrauterine origin; that is, differing size of chorionic villi, the presence of isolated molar villi and proliferative changes in the epithelium. A normal morphological villous pattern was extremely rare. The second group (146 cases, 44.41 per cent) showed all the morphological signs of transition to blighted ova. Most villi were well-vascularized but there were more molar villi, and proliferative and degenerative changes were seen in the epithelium. Group three (132 cases, 40.19 per cent) showed the full picture of a blighted ova. The morphological pattern of the extrauterine blighted ova was similar to that seen in the blighted ova of intrauterine origin, the only difference being that the vascularization of the villi was more pronounced in blighted ova of tubal pregnancies. Glucosaminoglycans were non-uniformly distributed over the villous stroma in the case of blighted ova, and they were present in greater concentration than in the case of abortions with normal placental findings: this is a useful method for differentiating abortions from blighted ova. It is apparent from the results of this investigation that the proportion of blighted ova is substantially greater in extrauterine than in intrauterine pregnancies. This suggests that unfavourable conditions of nidation within the tube have a decisive influence upon the genesis of blighted ova. Furthermore, the unfavourable environment appears adversely to influence trophoblastic development.

Familial trisomy 9p and spinal muscular atrophy: clinical, cytogenetic and embryological findings

The pre- and postnatal clinical, cytogenetic and embryological findings in a family suffering from trisomy 9p and spinal muscular atrophy are presented. The clinical picture of the "trisomy 9p" -syndrome is delineated. Concurrence of autosomal aberration and spinal muscular atrophy, probably of the Werdnig-Hoffmann type, is discussed.