G45.99: Transient cerebral ischaemic attack, unspecified Course of remission unspecified

Your brain was not receiving enough blood for a short time.

The brain is made up of several areas. For example, the cerebrum is used to think and plan actions. In the cerebellum, movements are initialized and coordinated. The brain stem is responsible for various unconscious tasks such as breathing. The brain stem passes into the spinal cord.

In your case, one or more blood vessels that supply blood to the brain closed up briefly. Blood vessels can close for different reasons. A blood clot can block the blood vessel, for example. Or fats and calcium may have been deposited in the blood vessel. This gradually makes the blood vessel narrower and it can sometimes close up entirely.

When the blood supply to the brain is insufficient for a short time, there may be various symptoms. The symptoms depend on which part of the brain is affected. For example, one may be unable to move certain parts of one’s body. One may also no longer feel certain areas of one’s body properly. One may have difficulties with speaking. Or one’s vision may be impaired.

The symptoms vanished after a short time.

Additional indicator

On medical documents, the ICD code is often appended by letters that indicate the diagnostic certainty or the affected side of the body.

  • G: Confirmed diagnosis
  • V: Tentative diagnosis
  • Z: Condition after
  • A: Excluded diagnosis
  • L: Left
  • R: Right
  • B: Both sides

Further information


This information is not intended for self-diagnosis and does not replace professional medical advice from a doctor. If you find an ICD code on a personal medical document, please also note the additional indicator used for diagnostic confidence.
Your doctor will assist you with any health-related questions and explain the ICD diagnosis code to you in a direct consultation if necessary.


Provided by the non-profit organization “Was hab’ ich?” gemeinnützige GmbH on behalf of the Federal Ministry of Health (BMG).