No follow-up assessments were noted - with the commissioner's report finding the optometrist's failures would have been met with "severe disapproval" by his peers.
Fourteen months later, the usually friendly, chatty boy had developed a severe headache and was having increasing vision problems. He was unable to walk straight, had started rubbing his forehead and banging his head against the wall, couldn't see or read and was barely talking.
The GP sent him to hospital where a CT scan found a craniopharyngioma, a type of brain tumour.
A week later the boy had surgery to remove the tumour. After the surgery, he was completely blind in his right eye and had very poor vision in his left eye.
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Duggal said the optometrist had failed the boy in several ways. He should have taken steps to test the boy's vision in his right eye, and considered differential diagnoses before deciding on the diagnosis.
He also had poor record keeping, did not make an appropriate referral or institute an ongoing treatment plan, and he did not schedule regular assessments to see if the boy's vision was getting better.
The optometrist's practice - which he owned - was also found liable for the inadequate care provided, among other failings. Duggal recommended the practice take steps to educate staff and review its processes.
Duggal recommended that the optometrist apologise for his breach of the Code of Health.
The optometrist, who retired in 2015, said he apologised "profusely" to the family and was "profoundly regretful". He had "contemplated and agonised" over why he misdiagnosed the boy's eyesight problem.
Duggal recommended the Optometrists and Dispensing Opticians Board may want to review his competence if he returns to clinical practice.