Morphological features assessment
- MRI
- CT
- Automated pupillometry
- Neurological pupillary index (NPi) has a suggested association with ICP.
- Normal pupil reactivity the average ICP was 19.6 mmHg, whereas in patients with abnormal pupillary reactivity the average ICP was 30.5 mmHg
- Pupil abnormalities were detectable 15.9 h before important increases in ICP, suggesting that NPi may provide early warning of intracranial hypertension.
- See Oddo 2023
Physiological changes assessment
- Transcranial Ultrasound Doppler
- Intracranial hypertension produces specific changes in cerebral blood flow velocity and waveform with diastolic flow velocity being particularly sensitive
- Gosling Pulsatility Index (gPI) is one of the first parameters derived from the TCD for ICP assessment, but its clinical utility is questionable due to its poor precision as it is importantly influenced by changes in arterial blood pressure and carbon dioxide
- A larger multicenter study of TCD (IMPRESSIT) including 262 patients has been concluded and it confirmed a high negative predictive value for intracranial hypertension (ICP > 20 mmHg = 91.3%, > 22 mmHg = 95.6%, > 25 mmH g = 98.6%)
- Sonographic measurement of optic nerve sheath diameter (ONSD)
- Optic nerve sheath (ONS) is continuous with the dura mater of the brain, and therefore surrounds the subarachnoid space containing CSF
- As the ONS is distensible, when there is an increase in CSF pressure the ONSD enlarges
- Different ONSD thresholds have been proposed ranging from 4.5 and 6 mm.
- Tympanometry,
- Near-infrared spectroscopy,
- Electroencephalography,
- Otoacoustic emissions assessment
Made with Bullet