Conjoined twins cephalopagus janiceps monosymmetros: a case report

We present an extremely rare case of Janiceps type of female cephalopagus conjoined twins. Various pathological mechanisms that may be responsible for abnormal morphological development (limited to the conjoined part and normal morphological development in free lower abdomen and pelvis) are discussed.

Conjoined twins were obtained from a hospital, fixed in formalin, and dissected to observe and report the abnormalities present.

Anatomical features included development of normal face on one side, rudimentary face (two pinna only) on the opposite side, two cerebra each connected to the eye ball of its own side byoptic nerve without any chiasma formation, two brain stems, two spinal cords, normally developed vertebral columns, four upper limbs, four lower limbs, a single shared foregut and small intestine up to Meckel's diverticulum beyond which it duplicated for the two twins, patent large intestines and anal canals. The genitourinary system was developed normally in both twins. The heart of one twin was relatively hypoplastic with the lungs. The liver was herniated on one side and the other side it was hypoplastic without any herniation. Gall bladder was absent on both sides. Conjoined hepatic ducts from both livers and the only pancreatic duct drained into esophagogastric junction.

We propose that the development of upper abnormally conjoined parts and lower normally developed parts of the body of both the twins may be attributed to the factors associated with variable degrees of the conjoining, dysgenetic (developmental) defects, and deformations because of crowding in utero.