This paper proposes a secure medical data hiding system that integrates hybrid AES-256 and ECC-256 encryption with Hamming-LSB-OPAP steganography. Patient information is first encrypted and structured into a QR code, which is then invisibly embedded into grayscale medical images. The system is evaluated based on imperceptibility metrics such as PSNR, SSIM, and MSE under various attack conditions, including Gaussian noise, salt-and-pepper noise, and JPEG compression. Experimental results demonstrate that the proposed method achieves an average PSNR of 51.31 dB, SSIM of 0.9965, and MSE of 0.48, indicating minimal distortion and high visual quality. Although QR decoding from the stego images was unsuccessful, the limitation is acknowledged, and future work will explore transform-domain embedding to improve robustness against distortion.