A pupil who carried out a savage attack on a teacher and left her lying lifeless in a pool of blood has been allowed to walk free from court . Secondary school teacher Carol Shaw's life was endangered and she was left scarred for life after being picked up and dumped head-first on a concrete floor. Ms Shaw was knocked unconscious after being hurled "like a ragdoll" by angry pupil Kieran Matthew, 18, from Dundee . Shortly after carrying out the vicious attack on 22 March 2024, the teenage pupil put his feet up on another teacher's desk and said: "The stupid cow deserved it." Sheriff Tim Niven-Smith said: "It is difficult to imagine a more serious assault, having regard to the consequences of your attack for Ms Shaw. It is not over-egging the pudding or exaggerating to say your attack has affected her life in every aspect. She is permanently disfigured. Photos show an extensive, significant scar on her head. "Until her promotion, she was the safe person for you to seek sanctuary with if you felt overwhelmed. She has dedicated her life to vulnerable school children such as you. You have robbed her of her career as she has been unable to go back to school due to panic attacks, nightmares and night terrors as a result of this assault." Join the Daily Record's WhatsApp community here and get the latest news sent straight to your messages. He told Matthew the offence merited 18 months in custody , but said it would be reduced for an early guilty plea. He said it would then fall within the sentencing rules on avoiding short-term sentences [under 12 months] for first offenders if an alternative is available. Matthew was placed under social work supervision for three years and ordered to attend Mentoring for Men and Designer Skills courses including anger management. He also placed Matthew on a Restriction of Liberty Order for 12 months from 9pm to 7am each night. Dundee Sheriff Court heard how the St Paul's Academy teacher was left with a highly visible Y-shaped scar on her head and had been too traumatised to return to work. Matthew, who has attention deficit hyperactivity disorder [ADHD] and an "extremely low" IQ range between 47 and 59, admitted attacking and injuring the teacher. The horrific assault took place after Matthew, who was in S5 at the Dundee school, refused to get changed separately from other pupils before a PE class. This measure - agreed by Matthew, his foster mum and the school - had been put in place because of previous aggression towards other children. Fiscal depute Laura Bruce said Matthew was described as a "couple of years behind" in his development and was educated outside mainstream classes. On the afternoon in question, six foot tall Matthew was said to have been " agitated and heightened" over the pre-PE changing. The teacher who would be attacked was deemed to be a "safe" person for him and had previously succeeded in de-escalating volatile incidents. She took the decision to have two other teachers and pupils placed in a locked classroom away from Matthew, who sat with his head down at a table. Mrs Bruce said: "The accused then realised they had gone to the ICT class and moved towards the door and said 'I'm f*****g going in there too'. He tried to exit to the corridor where Ms Shaw had her back to him. "She recalls him gripping her in a rugby-style grip with her arms pinned to her sides and the next thing she felt was the horrific impact of her head striking the floor." The court heard the teacher blacked out momentarily but regained consciousness and made a bloody handprint on the wall as she tried to get to her feet. Staff came to her aid after she screamed for help while bleeding profusely. "She was blinded by her own blood, which covered her face and top with a large amount of blood seen on the floor," Mrs Bruce said. "Another teacher had witnessed the accused lift her completely off her feet, throwing her to the floor deliberately and landing headfirst. Another said she appeared to be like a ragdoll flying through the air. The accused sat at a teacher's desk, with his feet on the desk and using his mobile phone. He told a teacher 'Sir, it wasn't an outburst of anger. She deserved it'." During a phone call to tell someone he hit a teacher, Matthew again said "she deserved it". He later banged on the desk and said: "The stupid cow deserved it." A colleague took the injured teacher to Ninewells Hospital because of an expected 20-minute wait for an ambulance. She was given ten stitches and had to return for a CT scan because she was confused and unable to finish sentences. The woman was diagnosed with concussion and plastic surgeon Dr Ketki Kaushal said the assault could have been life-threatening. After being cautioned and charged, Matthew, of Dundee, replied: "I am sorry." He pled guilty to seizing the teacher's neck and body, throwing her to the floor, causing her to strike her head and be rendered unconscious. He admitted the assault was to her severe injury, permanent disfigurement and the danger of her life. Solicitor Theo Finlay, defending, said Matthew had moved to foster care as a young child after being subjected to abuse in his biological family home. Mr Finlay said: "He has had longstanding issues managing his emotions. It is likely he was already in a heightened condition. He experiences nightmares and requires to be medicated. "That is attributed to childhood abuse. He needs prompts to eat and struggles in noisy or busy environments. He was not being allowed into the changing room and had feelings of unfairness. "He described becoming agitated. The teacher moved others away, which made him feel more agitated and singled out. At school he felt intensely disliked and frequently provoked by his peers." Don't miss the latest news from around Scotland and beyond - Sign up to our daily newsletter here.