| 00 | 0. PROCEDURES AND INTERVENTIONS , NOT ELSEWHERE CLASSIFIED |
| 01-05 | 1. OPERATIONS ON THE NERVOUS SYSTEM |
| 06-07 | 2. OPERATIONS ON THE ENDOCRINE SYSTEM |
| 08-16 | 3. OPERATIONS ON THE EYE |
| 17 | 3A. OTHER MISCELLANEOUS DIAGNOSTIC AND THERAPEUTIC PROCEDURES |
| 18-20 | 4. OPERATIONS ON THE EAR |
| 21-29 | 5. OPERATIONS ON THE NOSE, MOUTH, AND PHARYNX |
| 30-34 | 6. OPERATIONS ON THE RESPIRATORY SYSTEM |
| 35-39 | 7. OPERATIONS ON THE CARDIOVASCULAR SYSTEM |
| 40-41 | 8. OPERATIONS ON THE HEMIC AND LYMPHATIC SYSTEM |
| 42-54 | 9. OPERATIONS ON THE DIGESTIVE SYSTEM |
| 55-59 | 10. OPERATIONS ON THE URINARY SYSTEM |
| 60-64 | 11. OPERATIONS ON THE MALE GENITAL ORGANS |
| 65-71 | 12. OPERATIONS ON THE FEMALE GENITAL ORGANS |
| 72-75 | 13. OBSTETRICAL PROCEDURES |
| 76-84 | 14. OPERATIONS ON THE MUSCULOSKELETAL SYSTEM |
| 85-86 | 15. OPERATIONS ON THE INTEGUMENTARY SYSTEM |
| 87-99 | 16. MISCELLANEOUS DIAGNOSTIC AND THERAPEUTIC PROCEDURES |