Rambodoc at large

There is something about the phenomenon of twins that has fascinated mankind for centuries. Luv and Kush were Lord Rama’s sons, and find special mention in the mythology of the time. Apollo and Diana were twins, each remarkable in their own way. In culture, twins have a special pride of place—nowhere more so than in India, where kids have grown up on Sita and Gita, Ram and Shyam, apart from innumerable clones and clowns in latter day Govinda starrers.
The world of medicine also boasts of amazing biological accidents. In the phenomenon of ‘vanishing fetus’ one of the twins may just disappear when ultrasound is done during the mother’s pregnancy, a result of fetal death and disintegration. A fetus can grow parasitically inside its twin, a condition called ‘fetus in fetu’.
Another twinning phenomenon is the occurence of conjoined twins. This occurs when the group of cells formed by fertilization, the zygote, splits into two, but the divisions somehow re-unite at one point. So these twins stay united at the chest, buttock, belly, back or the head.
Some facts about conjoined twins:
• They occur once in every 40,000 births
• Indians are more prone to have conjoined twins
• 75% of them die within 24 hours of birth
• Females outnumber males 3:1
• The twins are always of the same sex
• Though they share the same body and may even share the same brain, they have different personalities, even different sex drives. Peculiarly, their thoughts may be common
Chang and Eng were conjoined twins born in Thailand in the 19th century who became famous after joining the travelling circus of PT Barnum, the famous entertainer. These men, who were given the name of Siamese twins, raised between them an astounding 23 children, underscoring once again the remarkable nature of these special human beings to live like other normal human beings.
There was a lot of buzz about the Indian twins who are joined at the head and due for surgery in New Delhi. What exactly was the issue there?
Twins who are joined at the head may have separate brains but may share the same blood vessels. Obviously, the hospital has to be really equipped for this. In an OR like this, there would be a calendar rather than a clock to time the surgery! The surgery has to involve division of the main vein, the sagittal sinus, which is very hazardous. The much-hyped Iranian twins who underwent surgery in Raffles Hospital, Singapore in 2003 died because the main vein bled severely on separation. So difficult is the surgery that teams of surgeons operate for 18 to 40 hours, and may stage the surgery into several installments.
Twin separation can be a fatal and futile exercise, leaving one or both dead. This kind of surgery, the cost of which runs into crores, has raised several ethical issues. How does a doctor decide which twin can live and which allowed to die? Why risk a separation when both could die? The answer is that the twins take the decision to risk life. Informed consent largely solves the ethical dilemma here. Unfortunately, in all the cases where the doctors decided to sacrifice the life of one twin, the other also died.
Another issue is the tendency of the hospitals involved in twin separation surgery to use these cases to launch high voltage publicity, raising hopes and then disappointing everybody, as happened to the Iranian twins in Singapore.
A couple of successful cases of separation of twins joined at the head (craniopagus) has encouraged the neurosurgical community to try more to provide a better quality of life for these unfortunate pairs. Who says medicine is not a noble profession?