Effect of Ultrasound-guided Pterygopalatine Fossa Block on Postoperative Pain Relief in Paediatric Adenotonsillectomy under General Anaesthesia: A Randomised Controlled Trial. - BYREDDY, BHASKARA; KALYANASUNDARAM, AKALYA; RAMACHANDRA, MADHUMALA HASSAN; RAMACHANDRAIAH RANGADHAMAIAH (Journal of Clinical & Diagnostic Research, 2026)