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Testing of autonomic nervous system function, specifically sudomotor function, is a diagnostic procedure aimed at evaluating the small nerve fibers that are associated with sweat glands. This type of testing is crucial for understanding how well the autonomic nervous system is functioning, particularly in relation to sweat production. The procedure encompasses various methodologies, allowing the physician to select one or more tests based on the patient's specific needs and clinical indications. Among the available tests are the quantitative sudomotor axon reflex test (QSART), silastic sweat imprint, thermoregulatory sweat test, and assessments of changes in sympathetic skin potential. Each of these tests provides valuable insights into the autonomic nervous system's control over sweat glands, which can be affected by a range of conditions. The QSART involves measuring baseline skin temperature and sweat output, followed by stimulation of sweat production through electrical means. The silastic sweat imprint captures the sweat droplets on a silastic material, while the thermoregulatory sweat test utilizes an indicator powder to visually demonstrate sweat production under heat exposure. Additionally, changes in sympathetic skin potential are evaluated through electrical stimulation, allowing for a comprehensive assessment of autonomic nerve function. The results from these tests are meticulously analyzed, and a detailed report is generated by the physician to aid in diagnosis and treatment planning.
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The testing of autonomic nervous system function, specifically sudomotor function, is indicated for various clinical scenarios where the evaluation of small nerve fibers linked to sweat glands is necessary. The following conditions may warrant this testing:
The procedure for testing autonomic nervous system function through sudomotor testing involves several distinct steps, each designed to assess different aspects of sweat gland function.
After the completion of the sudomotor testing, the physician will review the results obtained from the various tests. A comprehensive written report detailing the findings will be generated, which may include interpretations of the data and recommendations for further evaluation or treatment if necessary. Patients may be advised on any specific post-procedure care, although no extensive recovery period is typically required. The physician will discuss the implications of the test results with the patient, addressing any concerns and outlining potential next steps in management or treatment based on the findings.
| Short Descr | AUTONOMIC NRV SYST FUNJ TEST | Medium Descr | TESTING AUTONOMIC NERVOUS SYSTEM FUNCTION | Long Descr | Testing of autonomic nervous system function; sudomotor, including 1 or more of the following: quantitative sudomotor axon reflex test (QSART), silastic sweat imprint, thermoregulatory sweat test, and changes in sympathetic skin potential | 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 | STV-Packaged Codes | Type of Service (TOS) | 1 - Medical Care | Berenson-Eggers TOS (BETOS) | T2D - Other tests - other | MUE | 1 | CCS Clinical Classification | 7 - Other diagnostic nervous system procedures |
| 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. | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | 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. | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | 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 | GA | Waiver of liability statement issued as required by payer policy, individual case | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure | GZ | Item or service expected to be denied as not reasonable and necessary | GW | Service not related to the hospice patient's terminal condition | GC | This service has been performed in part by a resident under the direction of a teaching physician | RT | Right side (used to identify procedures performed on the right side of the body) | 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. | KX | Requirements specified in the medical policy have been met | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | 25 | Significant, separately identifiable evaluation and management service by the same physician or other qualified health care professional on the same day of the procedure or other service: it may be necessary to indicate that on the day a procedure or service identified by a cpt code was performed, the patient's condition required a significant, separately identifiable e/m service above and beyond the other service provided or beyond the usual preoperative and postoperative care associated with the procedure that was performed. a significant, separately identifiable e/m service is defined or substantiated by documentation that satisfies the relevant criteria for the respective e/m service to be reported (see evaluation and management services guidelines for instructions on determining level of e/m service). the e/m service may be prompted by the symptom or condition for which the procedure and/or service was provided. as such, different diagnoses are not required for reporting of the e/m services on the same date. this circumstance may be reported by adding modifier 25 to the appropriate level of e/m service. note: this modifier is not used to report an e/m service that resulted in a decision to perform surgery. see modifier 57 for significant, separately identifiable non-e/m services, see modifier 59. | 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). | 53 | Discontinued procedure: under certain circumstances, the physician or other qualified health care professional may elect to terminate a surgical or diagnostic procedure. due to extenuating circumstances or those that threaten the well being of the patient, it may be necessary to indicate that a surgical or diagnostic procedure was started but discontinued. this circumstance may be reported by adding modifier 53 to the code reported by the individual for the discontinued procedure. note: this modifier is not used to report the elective cancellation of a procedure prior to the patient's anesthesia induction and/or surgical preparation in the operating suite. for outpatient hospital/ambulatory surgery center (asc) 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). | 58 | Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period: it may be necessary to indicate that the performance of a procedure or service during the postoperative period was: (a) planned or anticipated (staged); (b) more extensive than the original procedure; or (c) for therapy following a surgical procedure. this circumstance may be reported by adding modifier 58 to the staged or related procedure. note: for treatment of a problem that requires a return to the operating/procedure room (eg, unanticipated clinical condition), see modifier 78. | 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.) | 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. | 99 | Multiple modifiers: under certain circumstances 2 or more modifiers may be necessary to completely delineate a service. in such situations modifier 99 should be added to the basic procedure, and other applicable modifiers may be listed as part of the description of the service. | AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | 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 | LT | Left side (used to identify procedures performed on the left side of the body) | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | 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 | 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 | SA | Nurse practitioner rendering service in collaboration with a physician | SC | Medically necessary service or supply | 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 |
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| 2013-01-01 | Changed | Short Descriptor changed. |
| 2010-01-01 | Changed | Code description changed. |
| 1997-01-01 | Added | First appearance in code book in 1997. |
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