A system that is used to lock an accessory, for example a cystoscope that is locked to a hand held device that provides prostate ablation therapy, within a housing includes a sliding lock device (SLD) which receives and surrounds at least a portion of the cystoscope in an opening. Once the cystoscope is positioned within the SLD, the user may slide a cover to engage a tab of the cystoscope and secure the cystoscope within the SLD and the housing. The SLD also includes a mechanism for prohibiting cystoscope rotation. After the cystoscope is locked, the SLD allows for a defined amount of axial movement to facilitate prostate viewing and the deployment of prostate ablation therapy. Alternatively, the cover may slide in a rotational manner to secure the cystoscope.