<p>Saliency in images refers to the attention-grabbing part of the image. In medical imaging, the salient portion contains information important for diagnosis. Securing salient information is of vital importance in the healthcare system. Conventional encryption schemes, including Advanced Encryption Standard (AES) ensure a high level of security of digital data but vulnerable to cropping and data loss attacks, which cause the loss of salient information. This work introduces a lightweight saliency preserving encryption scheme that follow substitution permutation based architecture. In the substation phase the proposed encryption scheme utilizes Deoxyribonucleic Acid (DNA) generated highly nonlinear Boolean functions. To disperse the salient information the proposed scheme utilizes logistic chaotic map based block permutation algorithm. Compare to the AES, the proposed encryption scheme have high throughput which shows its feasibility for real time implementation. The security analysis, including NIST randomness tests, histogram analysis, correlation coefficient, sensitivity and information entropy analysis shows the immunity against statistical and differential attacks. The data loss attack and noise analysis shows the strength of the encryption scheme in securing the saliency of medical images. The key analysis shows the sensitivity to key and immunity to exhaustive key search attacks. This approach provides an efficient and secure solution for medical image transmission and storage in telemedicine, cloud-based healthcare, and intelligent medical systems.</p>