Thanatophoric Dysplasia and the Brain—A Perinatal Pathology Study

Abstract

AbstractThe purpose of this article is to analyse all cases of thanatophoric dysplasia and document the associated CNS anomalies. A retrospective study of all cases of thanatophoric dysplasia diagnosed in the department of perinatal pathology from January 2009 to December 2016. The various associated findings with due reference to the CNS manifestations were analyzed. During the study period, 7741 foetal autopsies were done, of which 24 (0.31%) were diagnosed to have thanatophoric dysplasia. The brain of one case was autolysed and hence, this had been excluded from this study. Of the 23 cases, 19 were of type 1 (83%) and 4 were of type 2 (17%). CNS anomalies were present in all. In our series, the characteristic findings seen in TD type 1 were enlarged skull, short neck, narrow thorax, protuberant abdomen, severe rhizoacromelic shortening of all four limbs with bowing of lower limbs. Whereas, type 2 manifested with large clover leaf skull with frontal bossing, short neck, short ribs, protuberant abdomen, severe rhizoacromelic shortening of all four limbs. Both the types had their characteristic fetogram findings. Central nervous system anomalies were seen in all 23 cases; which were multiple bilateral clefts seen in the inferior surface of the temporal lobe and medial surface of the occipital lobe. There were no noticeable differences in CNS abnormalities between TD type I and II. Clefting disorders consistently seen in the present series and in other reports calls for attention to be given to cortical malformations of the temporal lobe. This constellation of brain abnormalities needs recognition in fetal imaging and we propose that this should be included in the guidelines for diagnosis of thanatophoric dysplasia.