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(ŏf-thăl″mō-rē′ă) [″ + rhoia, flow] Discharge from the eye.


(of″thal′mŏ-skōp″) [ophthalmo- + -scope] An instrument used for examining the interior of the eye, esp. the retina. ophthalmoscopic (″thal″mŏ-skop′ik), adj.


(of″thal-mos′kŏ-pē) [ophthalmo- + -scopy] Examination of the interior of the eye with an ophthalmoscope. SYN: funduscopy; optic nerve head examination.

direct o. Observation of an upright image in the ocular fundus.

indirect o. Observation of an inverted image in the ocular fundus.

-opia, -opy

[Gr. -ōpia, fr. ōps, eye, face + -ia] Suffixes meaning vision. SEE: -opsia.


(ō′pē-ăt) Any drug containing or derived from opium.

opiate treatment agreement

SEE: drug contract.

opiate withdrawal syndrome

Physiological responses to abrupt cessation of the use of addictive substances. The symptoms include chills, runny nose, yawning, irritability, insomnia, and cramping. Physical signs of withdrawal include elevated blood pressure, diaphoresis, diarrhea, and muscle spasms. Discomfort peaks at 48 to 72 hr; however, symptoms persist for 7 to 10 days. Treatment includes methadone and psychological support and counseling.


Acronym for other potentially infectious materials.


(ō′pē-oyd) [L. opium, opium, + Gr. eidos, form, shape] 1. Any synthetic narcotic not derived from opium. 2. Indicating substances such as enkephalins or endorphins occurring naturally in the body that act on the brain to decrease the sensation of pain.

opioid analgesic overdose

Opiate poisoning


(ō-pĭs′thē-ŏn″) [NL. fr. Gr. opisthen, back, in the rear] The craniometric point at the middle of the lower border of the foramen magnum.

opistho-, opisth-

[Gr. opisthen, behind, in the rear] Prefixes meaning backward, behind.


(ō″pĭs-thor-kī′ă-sĭs) [Opisthorchis + -iasis] Infestation of the liver by flukes of the genus Opisthorchis. SEE: Opisthorchis.


(ō″pĭs-thor′kĭs) [opistho- + orchis, testicle] A genus of liver flukes endemic to Asia.

O. felineus SEE: O. tenuicollis.

O. viverrini A species endemic in Southeast Asia. SEE: opisthorchiasis.


(ō″pĭs-thŏt′ō-nŏs) [″ + tonos, tension] A tetanic spasm in which head and heels are bent backward and the body is bowed forward. This type of spasm is seen in strychnine poisoning, tetanus, epilepsy, the convulsions of rabies, and in severe cases of ...

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