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The CPT® Code 77300 refers to the process of basic radiation dosimetry calculation, which is a critical component in the field of radiation therapy. This procedure involves a series of calculations performed by a dosimetrist to determine the appropriate radiation dose that should be delivered to a patient during their treatment. The calculations take into account various factors that influence the radiation dose, ensuring that it is both accurate and safe. Key elements considered in this process include the central axis depth dose calculation, which assesses how radiation penetrates different depths of tissue, and the Tissue Dose Factor (TDF) and Normalized Standard Dose (NSD) calculations, which help in evaluating the effectiveness of the radiation treatment based on the patient's specific conditions. Additionally, the procedure includes gap calculations and off-axis factors, which account for variations in radiation distribution due to the geometry of the treatment setup. The dosimetrist also evaluates tissue inhomogeneity factors, which consider the differing densities of tissues that may affect radiation absorption. Furthermore, the calculation of non-ionizing radiation surface and depth dose is included as required during the course of treatment. It is important to note that these calculations are performed only when prescribed by the treating physician, emphasizing the necessity of a collaborative approach in radiation therapy planning. The accurate execution of these calculations is essential to minimize the risk of errors in radiation dose delivery, thereby ensuring that patients receive the prescribed dose effectively and safely.
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The procedure associated with CPT® Code 77300 is indicated for patients undergoing radiation therapy where precise dosimetry calculations are essential for effective treatment. The following conditions may warrant the use of this code:
The procedure for CPT® Code 77300 involves several critical steps to ensure accurate radiation dosimetry calculations. Each step is essential for the safe delivery of radiation therapy.
After the completion of the dosimetry calculations associated with CPT® Code 77300, it is essential to review and verify the calculations before the actual delivery of radiation therapy. This verification process helps to minimize the risk of errors and ensures that the prescribed dose is accurately delivered to the patient. The dosimetrist must document all calculations and any adjustments made during the process. Continuous monitoring and assessment of the treatment plan may be necessary throughout the course of therapy to accommodate any changes in the patient's condition or treatment response. Proper communication with the treating physician is also crucial to ensure that any modifications to the treatment plan are made in a timely manner, maintaining the safety and effectiveness of the radiation therapy.
| Short Descr | RADIATION THERAPY DOSE PLAN | Medium Descr | BASIC RADIATION DOSIMETRY CALCULATION | Long Descr | Basic radiation dosimetry calculation, central axis depth dose calculation, TDF, NSD, gap calculation, off axis factor, tissue inhomogeneity factors, calculation of non-ionizing radiation surface and depth dose, as required during course of treatment, only when prescribed by the treating physician | Status Code | Active Code | Global Days | XXX - Global Concept Does Not Apply | PC/TC Indicator (26, TC) | 1 - Diagnostic Tests for Radiology Services | Multiple Procedures (51) | 0 - No payment adjustment rules for multiple procedures apply. | Bilateral Surgery (50) | 0 - 150% payment adjustment for bilateral procedures does NOT apply. | Physician Supervisions | 09 - Concept does not apply. | Assistant Surgeon (80, 82) | 0 - Payment restriction for assistants at surgery applies to this procedure... | Co-Surgeons (62) | 0 - Co-surgeons not permitted for this procedure. | Team Surgery (66) | 0 - Team surgeons not permitted for this procedure. | Diagnostic Imaging Family | 99 - Concept Does Not Apply | APC Status Indicator | Procedure or Service, Not Discounted when Multiple | ASC Payment Indicator | Radiology service paid separately when provided integral to a surgical procedure on ASC list; payment based on MPFS nonfacility PE RVUs. | Type of Service (TOS) | 6 - Therapeutic Radiology | Berenson-Eggers TOS (BETOS) | P7A - Oncology - radiation therapy | MUE | 10 | CCS Clinical Classification | 211 - Therapeutic radiology |
| 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. | 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. | TC | Technical component; under certain circumstances, a charge may be made for the technical component alone; under those circumstances the technical component charge is identified by adding modifier 'tc' to the usual procedure number; technical component charges are institutional charges and not billed separately by physicians; however, portable x-ray suppliers only bill for technical component and should utilize modifier tc; the charge data from portable x-ray suppliers will then be used to build customary and prevailing profiles | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | 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. | GC | This service has been performed in part by a resident under the direction of a teaching physician | Q6 | Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area | AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | X4 | Episodic/focused services: for reporting services by clinicians who provide focused care on particular types of treatment limited to a defined period and circumstance; the patient has a problem, acute or chronic, that will be treated with surgery, radiation, or some other type of generally time-limited intervention; reporting clinician service examples include but are not limited to, the orthopedic surgeon performing a knee replacement and seeing the patient through the postoperative period | X5 | Diagnostic services requested by another clinician: for reporting services by a clinician who furnishes care to the patient only as requested by another clinician or subsequent and related services requested by another clinician; this modifier is reported for patient relationships that may not be adequately captured by the above alternative categories; reporting clinician service examples include but are not limited to, the radiologist's interpretation of an imaging study requested by another clinician | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | CR | Catastrophe/disaster related | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | GW | Service not related to the hospice patient's terminal condition | 95 | Synchronous telemedicine service rendered via a real-time interactive audio and video telecommunications system: synchronous telemedicine service is defined as a real-time interaction between a physician or other qualified health care professional and a patient who is located at a distant site from the physician or other qualified health care professional. the totality of the communication of information exchanged between the physician or other qualified health care professional and the patient during the course of the synchronous telemedicine service must be of an amount and nature that would be sufficient to meet the key components and/or requirements of the same service when rendered via a face-to-face interaction. modifier 95 may only be appended to the services listed in appendix p. appendix p is the list of cpt codes for services that are typically performed face-to-face, but may be rendered via a real-time (synchronous) interactive audio and video telecommunications system. | GZ | Item or service expected to be denied as not reasonable and necessary | 79 | Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period: the individual may need to indicate that the performance of a procedure or service during the postoperative period was unrelated to the original procedure. this circumstance may be reported by using modifier 79. (for repeat procedures on the same day, see modifier 76.) | Q0 | Investigational clinical service provided in a clinical research study that is in an approved clinical research study | 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). | 52 | Reduced services: under certain circumstances a service or procedure is partially reduced or eliminated at the discretion of the physician or other qualified health care professional. under these circumstances the service provided can be identified by its usual procedure number and the addition of modifier 52, signifying that the service is reduced. this provides a means of reporting reduced services without disturbing the identification of the basic service. note: for hospital outpatient reporting of a previously scheduled procedure/service that is partially reduced or cancelled as a result of extenuating circumstances or those that threaten the well-being of the patient prior to or after administration of anesthesia, see modifiers 73 and 74 (see modifiers approved for asc hospital outpatient use). | 56 | Preoperative management only: when 1 physician or other qualified health care professional performed the preoperative care and evaluation and another performed the surgical procedure, the preoperative component may be identified by adding modifier 56 to the usual procedure number. | 77 | Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service. | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | GA | Waiver of liability statement issued as required by payer policy, individual case | LT | Left side (used to identify procedures performed on the left side of the body) | MG | The order for this service does not have applicable appropriate use criteria in the qualified clinical decision support mechanism consulted by the ordering professional | PD | Diagnostic or related non diagnostic item or service provided in a wholly owned or operated entity to a patient who is admitted as an inpatient within 3 days | PN | Non-excepted service provided at an off-campus, outpatient, provider-based department of a hospital | Q5 | Service furnished under a reciprocal billing arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area | 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) | RT | Right side (used to identify procedures performed on the right side of the body) | SA | Nurse practitioner rendering service in collaboration with a physician | X1 | Continuous/broad services: for reporting services by clinicians, who provide the principal care for a patient, with no planned endpoint of the relationship; services in this category represent comprehensive care, dealing with the entire scope of patient problems, either directly or in a care coordination role; reporting clinician service examples include, but are not limited to: primary care, and clinicians providing comprehensive care to patients in addition to specialty care | XP | Separate practitioner, a service that is distinct because it was performed by a different practitioner |
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| 2002-01-01 | Changed | Code description changed. |
| Pre-1990 | Added | Code added. |
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