Which diagnostic procedure can TPA certified ODs conduct?

TPA (Therapeutic Pharmaceutical Agents) certified optometrists in California have the authority to perform certain procedures and prescribe medications for various ocular conditions. Among the choices presented, the option regarding clinical lab testing under CLIA (Clinical Laboratory Improvement Amendments) is correct because TPA certified ODs can perform specific diagnostic tests as part of their practice. This includes certain tests that fall under the scope of CLIA, which governs laboratory testing in the United States to ensure accuracy and reliability.

Performing clinical lab testing allows optometrists to utilize diagnostic tools essential for managing and treating patients' eye conditions effectively. This capacity enhances their roles as primary eye care providers, allowing them to deliver more comprehensive care to their patients.

The other options are not aligned with the permissible scope of practice for TPA certified optometrists. While surgical interventions and CT scans are outside their scope, external exams are typically part of the foundational responsibilities of all optometrists, but they do not encompass the specificity indicated in the context of the question regarding TPA certification. Therefore, the ability to conduct clinical lab testing under CLIA accurately reflects the expanded responsibilities that TPA certification entails for optometrists in California.