1. Understanding ICD-9-CM Coding
Mary Jo Bowie MS, RHIA, RHIT
Regina Schaffer AAS, RHIA, CPC

2. Diseases of the Nervous System and Sense Organs
CHAPTER 11

3. Nervous System Controls all bodily activities Two main parts:
Central Nervous System (CNS)
Peripheral Nervous System (PNS)

5. Coding Diseases of Central Nervous System (CNS)
Inflammatory Diseases 320–326
Hereditary & Degenerative Diseases 330–337
Other Headache Syndromes 339
Other Diseases of the CNS 340–349

6. Category Codes for PNS and Sense Organs
Peripheral Nervous System 350–359
Eye and Adnexa 360–379
Ear and Mastoid Process 380–389

7. Inflammatory Diseases of CNS
Instructional notes can be difficult
Reference to Alphabetic and Tabular List
May require assignment of two codes

8. Meningitis Inflammation of the meninges Can be caused by:
Bacteria or nonbacterial
Viral
Aseptic
Manifestation of another disease
Code classification according to cause

9. Other Conditions
Encephalitis
Myelitis
Encephalomyelitis

10. Hereditary and Degenerative Diseases of CNS
Alzheimer’s Disease
Dementia
Parkinson’s Disease
Disorders of autonomic nervous system
Parasympathetic
Sympathetic—“fight-or-flight”

11. Other Disorders of CNS Multiple sclerosis Hemiplegia Hemiparesis
Cerebrovascular accident (CVA)
Cerebral palsy
Epilepsy

13. Disorders of PNS 12 pairs of cranial nerves
Identified by Roman numerals
Injury to any cranial nerves coded to these categories

15. Disorders of the Eye and Adnexa
Adnexa—accessory or appendage
Very detailed coding
Resources are very important to understanding eye anatomy
Conditions would include
Conjunctivitis
Cataracts

17. Diseases of the Ear and Mastoid Process
External, middle, and inner ear
Conditions encountered
Conductive hearing loss
Otosclerosis