A 50-STONE woman is starting an urgent battle to lose weight so she can fit in a brain scan machine. Terri Smith, 49 - thought to be the fattest woman in the world - is trapped in her bedroom in Cleveland, Ohio, US, unable to move, stand or roll over by herself. She suffers severe headaches and needs an MRI scan to check for a potential brain tumour but is too big to fit in a scanner or through the doors of a hospital. She is carrying at least five stone more than Britains heaviest woman Sharon Mevsimler, who died this year. Terri relies on loving husband Myron, 44, and oldest daughter Najah, 30, to do everything for her. She must be washed, fed and dressed on the bed. She said: My husband is my guardian angel. Hes stuck by me through everything. Most men would have left a long time ago, and who could blame them - but Myron is a living saint. Terri was always large - at age seven she weighed almost eight stone. She said: My nickname at school was fatso. No one wanted me on their sports team and that didnt help the fat. We grew up on soul food and no one thought anything about it. We never watched what we ate at all and we didnt know what was healthy and what wasnt. She faces a race against time to lose weight in a bid to qualify for gastric surgery. Terri, who has been bed-bound for three years, said: People must think, 'How could you let yourself get like that? Its awful how it creeps up on you. Once you cannot exercise it doesnt matter how healthily you eat, the weight just sticks. Youre not burning off a single calorie. The Sun Dr Dariush Saghafi said: Caring for someone of Terris size is very difficult. It is very hard to move and transport her. Hospitals do not have equipment to hold someone of her girth. We thought that it might be possible for Terri to have an MRI at the Cleveland Zoo in the machine used for the elephants and rhinos but the zoo does not have a licence for humans. The Sun