This means that two embryonic discs could only unite in locations where the ectoderm is absent. Moreover, the fusion occurs from neural folds of two separate, dorsally oriented embryonic discs, and the union can occur only after the ectoderm is disrupted to allow the neural and surface ectodermal layers to separate from each other. The union in craniopagus twins may happen at any portion of the calvarium. The juncture can involve either the entire diameter of the head or any portion of the head and can be positioned at a multitude of rotational angles. In fact, craniopagus twins are rarely found in a symmetrical union. Apart from this, the vertebral axes may have a straight line. Despite this, the angle of the vertebrae is the ultimate dictator in how the individuals heads actually face. The majority of twins face either the same way or the exact opposite direction. Medical procedures
Diagnosis
Conjoined twins, including craniopagus twins, can be diagnosed using standard ultrasound procedures during a pregnancy. In part because treatment of conjoined twins varies largely, many parents make the decision to terminate pregnancy due to the prognosis and quality-of -life issues. If the parents choose to continue the pregnancy, mother and babies will be closely monitored. In almost all cases, a C-section delivery is planned, often two to three weeks before the due date. Separation surgeries
After the twins are born, parents and doctors decide whether or not separation surgery is possible.
Secnidazole (trade names Flagentyl, Sindose, Secnil, Solosec) is a nitroimidazole anti-infective. Effectiveness in the treatment of dientamoebiasis has been reported. It has also been tested against Atopobium vaginae.In the United States, secnidazole is approved for the treatment of bacterial vaginosis and trichomoniasis in adult women. References


== Further reading ==