Why I had to modify a trephine and make a special scalp retractor

In 2005, I had perceived an idea to make trephine craniotomy more safe. I had been exposed to trephine craniotomy in 1984 January as I started my training in neurosurgery. From hatred for it I became a lover of it. Seeing Professor Banerji making a straight scalp incision and doing trephine craniotomy with Scoville trephine was an art for every body to appreciate.

Prof Banerji had picked up the art from original master WB Scoville when he visited on behalf of WFNS, CMC Vellore. All the brain tumours, aneurysms were accessed through trephine craniotomy. It became a hall mark of micro neurosurgery by the master craftsman Prof Banerji who celebrated his 80th birthday few months back and still continues to practice actively. Professor Banerji gave up smoking when he started micro neurosurgery because of fear of tremors in hands developing as a result of smoking.

My job as neurosurgeon which I started in 1987 involved operating many emergencies specially trauma patients. For limited contusions, intracerebral haematomas, extradural haematomas it became a very good choice as you could operate many patients one after the other. Gigli saw and perforators were not very good as wire used to become twisted and sometimes it would break and there is no neurosurgeon who has not seen perforator suddenly going inside brain.

Moreover multiple burr hole needed good biceps and left ugly calvarial defects. A guard on trephine which could be adjusted up and down is my original idea and so that it gets sort of locked by adding one more ring makes trephine a versatile instrument with no fear of it accidently going in. To make good exposure of bone author designed a scalp retractor with semicircular arms. It really exposes adequate bone for craniotomy and once applied does not need scalp haemostats for controlling bleeding from edges. It seems to have deeper teeth but that is designed to accomodate scalp on both edges. Further than this author has designed a method of craniotomy for operating bigger lesion(Karam Chand method of craniotomy is google searchable).