| PION | posterior ischemic optic neuropathy |
|---|---|
| PN | papillary necrosis; parenteral nutrition; penicillin; perceived noise; percussion note; periarteriti... |
| PNP | pancreatic polypeptide; para-nitrophenol; peak negative pressure; pediatric nurse practitioner; peri... |
| SSN | severely subnormal; subacute sensory neuropathy; suprasternal notch |
| TON | traumatic optic neuropathy |