A dog required a three hour life-saving operation after it was mauled by a "pit bull type" in Petts Wood.
Gillian Ewins, 61, of Sutherland Avenue, Biggin Hill, was walking 15-year-old Hermione across the railway bridge from Little Thrift to Petts Wood at around 3.30pm on March 5.
Suddenly the "pit bull type" - pale in colour with brown markings and a pink nose - appeared at the top of the steps off its lead.
Mrs Ewins said: "Before I could pick up my little dog the pit bull type was on her, savaging her.
"It went straight for her, even if it had been on a lead the man who owned the dog couldn't have held it.
"He eventually fought the dog off but by then my dog was very badly injured with a ripped abdomen.
"It looked like her guts were hanging out of her stomach.
"If he hadn't got the dog off she would have been dead at the scene."
Mrs Ewins took Hermione straight to the vet where she was operated on.
She added: "After the operation the vet told me there was a broken rib, tissue and muscle damage and penetration of the abdominal wall, which caused peritonitis.
"It was really bad. My dog's life was in the balance for several days.
"It is amazing she survived it. It was touch and go but she pulled through.
"She's perkier now. I hope she'll get her confidence back."
Mrs Ewins added she believes something needs to be done about breeds of dog with a dangerous reputation.
She said: "The whole experience has affected me and my family badly.
"Why do people who own dangerous dogs not realise that they should be muzzled when out in public?
"The fashion of owning these dogs as a status symbol is pathetic.
"I will be anxious about taking my dog out again.
"I am still fairly resilient but an older pensioner could have their life ruined by an incident like this."
A police spokesman said: "The owner of the dog is described as a white male, aged about 40 and about 6 foot tall.
"The dog is described as a white pit bull type dog with brown patches.
"This is obviously a very upsetting incident and we would like to take the opportunity to remind dog owners of their responsibility to control their pets at all times."