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The CPT® Code 84480 refers to the laboratory test for measuring total triiodothyronine (T3), a crucial hormone produced by the thyroid gland. T3 plays a significant role in regulating various metabolic processes within the body, including body temperature, growth, and heart rate. This test involves analyzing a blood sample to determine the levels of total T3, which encompasses both the bound and free forms of the hormone. Approximately 95% of T3 in the bloodstream is bound to proteins and is considered inactive, while the remaining 5% is free and biologically active. The measurement of total T3 is essential for assessing thyroid function, diagnosing conditions such as hyperthyroidism, and monitoring patients who have existing thyroid disorders. The total T3 test is performed using an electrochemiluminescent immunoassay, a sensitive and specific method for quantifying hormone levels in the blood. Understanding the levels of total T3 can provide valuable insights into a patient's thyroid health and overall metabolic status.
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The total triiodothyronine (T3) test, represented by CPT® Code 84480, is indicated for several clinical scenarios related to thyroid function. The following conditions may warrant the performance of this test:
The procedure for conducting the total T3 test involves several key steps to ensure accurate measurement of hormone levels. The following outlines the procedural steps:
After the total T3 test is performed, there are generally no specific post-procedure care requirements for the patient. However, patients may be advised to wait for the results, which are typically available within a few days. It is important for patients to follow up with their healthcare provider to discuss the results and any necessary next steps, especially if the test indicates abnormal T3 levels. Monitoring and further evaluation may be required based on the findings, particularly for those with existing thyroid conditions.
| Short Descr | ASSAY TRIIODOTHYRONINE (T3) | Medium Descr | ASSAY OF TRIIODOTHYRONINE T3 TOTAL TT3 | Long Descr | Triiodothyronine T3; total (TT-3) | Status Code | Statutory Exclusion (from MPFS, may be paid under other methodologies) | Global Days | XXX - Global Concept Does Not Apply | PC/TC Indicator (26, TC) | 9 - Not Applicable | Multiple Procedures (51) | 9 - Concept does not apply. | Bilateral Surgery (50) | 9 - Concept does not apply. | Physician Supervisions | 09 - Concept does not apply. | Assistant Surgeon (80, 82) | 9 - Concept does not apply. | Co-Surgeons (62) | 9 - Concept does not apply. | Team Surgery (66) | 9 - Concept does not apply. | Diagnostic Imaging Family | 99 - Concept Does Not Apply | CLIA Waived (QW) | No | APC Status Indicator | Conditionally packaged laboratory tests | Type of Service (TOS) | 5 - Diagnostic Laboratory | Berenson-Eggers TOS (BETOS) | T1H - Lab tests - other (non-Medicare fee schedule) | MUE | 1 | CCS Clinical Classification | 233 - Laboratory - Chemistry and Hematology |
| 90 | Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number. | Q4 | Service for ordering/referring physician qualifies as a service exemption | 59 | Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25. | GW | Service not related to the hospice patient's terminal condition | GA | Waiver of liability statement issued as required by payer policy, individual case | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | 26 | Professional component: certain procedures are a combination of a physician or other qualified health care professional component and a technical component. when the physician or other qualified health care professional component is reported separately, the service may be identified by adding modifier 26 to the usual procedure number. | 91 | Repeat clinical diagnostic laboratory test: in the course of treatment of the patient, it may be necessary to repeat the same laboratory test on the same day to obtain subsequent (multiple) test results. under these circumstances, the laboratory test performed can be identified by its usual procedure number and the addition of modifier 91. note: this modifier may not be used when tests are rerun to confirm initial results; due to testing problems with specimens or equipment; or for any other reason when a normal, one-time, reportable result is all that is required. this modifier may not be used when other code(s) describe a series of test results (eg, glucose tolerance tests, evocative/suppression testing). this modifier may only be used for laboratory test(s) performed more than once on the same day on the same patient. | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | GY | Item or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit | 51 | Multiple procedures: when multiple procedures, other than e/m services, physical medicine and rehabilitation services or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. the additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). note: this modifier should not be appended to designated "add-on" codes (see appendix d). | 76 | Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service. | AY | Item or service furnished to an esrd patient that is not for the treatment of esrd | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | GC | This service has been performed in part by a resident under the direction of a teaching physician | GZ | Item or service expected to be denied as not reasonable and necessary | Q0 | Investigational clinical service provided in a clinical research study that is in an approved clinical research study | QJ | Services/items provided to a prisoner or patient in state or local custody, however the state or local government, as applicable, meets the requirements in 42 cfr 411.4 (b) | QW | Clia waived test | SA | Nurse practitioner rendering service in collaboration with a physician | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service |
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| 2013-01-01 | Changed | Medium Descriptor changed. |
| 2011-01-01 | Changed | Short description changed. |
| Pre-1990 | Added | Code added. |
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