Dr Charlie Teo has dropped a defamation lawsuit against a University of Sydney urological surgery professor who criticised him on Twitter over the cost of his procedures.

Back in May, the neurosurgeon threatened to sue Professor Henry Woo over a series of tweets questioning his ethics for reportedly charging $60,000 to perform brain surgery on a child.

The tweets referred to media reports about a crowd-funding campaign that had raised more than $100,000 for Dr Teo to operate on a seven-year-old girl from Newcastle, NSW, with diffuse intrinsic pontine glioma.

Professor Woo suggested the surgery could have been performed in the public system at no charge given the patient was from NSW and asked whether Dr Teo’s personal fee was “really $60,000”.