S04.21XA — Injury of trochlear nerve, right side, initial encounter
ICD-10-CM
Prior Authorization
No Prior Auth Required
Code is covered without prior authorization (high confidence)
Documentation Required
- When NCSs and NEMG are performed on the same day for the same patient they must be reported on the same claim.
- When billing non-covered services/tests report unlisted neurological CPT 95999 and provide a description of the service/test in block 80 (Part A) or box 19 (Part B) or electronic equivalent; failure to include this information will result in Part A claims being returned and Part B claims rejected.
- All documentation must be maintained in the patient's medical record, be legible, include patient identification and dates of service, and include the legible signature of the responsible physician or non-physician practitioner.
- The submitted medical record must support the selected ICD-10-CM code(s), the submitted CPT/HCPCS code must describe the service performed, and the record must clearly document the medical necessity, the indication for ordering the test(s), and a clear diagnostic impression.
Key Coverage Criteria
- Nerve conduction studies (NCS) without needle electromyography (NEMG) are allowed for individuals being evaluated for carpal tunnel syndrome or tarsal tunnel syndrome when one of the diagnosis codes G56.01, G56.02, G56.03, G56.11, G56.12, G56.13, G56.21, G56.22, G56.23, G57.51, G57.52, or G57.53 is reported.
- NCS without NEMG is allowed for individuals with significant lymphedema in the affected extremity when diagnosis code I89.0 is reported in addition to the primary diagnosis.
- NCS without NEMG is allowed for individuals treated with anticoagulants when diagnosis code Z79.01 or Z79.02 is reported in addition to the primary diagnosis.
- Neurophysiology Evoked Potentials (NEPs) — including Somatosensory Evoked Potentials (SEPs), Brainstem Auditory Evoked Potentials (BAEPs/BAERs), and Visual Evoked Potentials (VEPs/VERs) — are covered when determined to be reasonable and necessary in accordance with LCD L34975.
- Nerve conduction studies (NCS) without needle EMG (NEMG) are allowed for individuals being evaluated for carpal tunnel syndrome or tarsal tunnel syndrome when one of the following ICD-10-CM codes is reported: G56.01, G56.02, G56.03, G56.11, G56.12, G56.13, G56.21, G56.22, G56.23, G57.51, G57.52, or G57.53.
- NCS without NEMG is allowed for individuals with significant lymphedema in the affected extremity when ICD-10-CM code I89.0 is reported in addition to the primary diagnosis.
12 Active Policies
L34859 — Nerve Conduction Studies and Electromyography
J09
A57123 — Billing and Coding: Nerve Conduction Studies and Electromyography
J09
A56773 — Billing and Coding: Neurophysiology Evoked Potentials (NEPs)
J12
L34975 — Neurophysiology Evoked Potentials (NEPs)
J12
L35081
Related Codes
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