Table 1.
Demographic details of 20 patient.
Table 2.
An example of F value for the significance of the regression equation.
Fig 1.
Relationship between initial ICP and the indicator "a" in parabolic equations.
N = 139. Regression line is shown; regression equation: y = 0.024x-0.145; R2 = 0.156.
Table 3.
The statistics for the indicator “a” in different intracranial conditions.
Table 4.
Summary of clinical features in 7 patients with rapid elevation of indicator “a”.
Fig 2.
The change of brain CT scans in a spontaneous ICH patient (case 1) in 9 days.
Fig 2a shows that the initial brain CT revealed left thalamic hemorrhage, intraventricular hemorrhage, and bilateral dilated ventricle. Fig 2b shows that on POD 6, the brain CT revealed that left thalamic hemorrhage was stationary. The brain parenchyma was tight, especially on the left side. Severe peri-hematoma edema was noted and the brain was shifted to right side. Two EVD tubes were placed in the bilateral frontal horns and the ventricles became slim. Fig 2c shows that the follow-up brain CT on POD 9 revealed that the hematoma and perifocal edema regressed with significantly less mass effect. The brain parenchyma became slack with clear margin of sulci. The EVD tubes were in bilateral enlarged lateral ventricles.
Fig 3.
The change of mean of indicator “a” in parabolic P-V curve in case 1.
The mean of indicator “a” in parabolic P-V curve declined from 0.688 on POD 1 to 0.272 on POD 4. However, it started elevating on POD 4 and reached the highest point (0.76) on POD 6. The indicator “a” declined again after POD 6 and it was 0.283 on POD 9.
Fig 4.
The change of brain CT scans in an intraventricular hemorrhage with hydrocephalus patient (case 2) in 7 days.
Fig 4a. and 4b show that the initial brain CT revealed a thalamic vascular lesion and intraventricular hemorrhage in enlarged bilateral ventricles. A right VP shunt tube was placed in the right frontal horn. Fig 4c. and 4d show that the follow-up brain CT on POD 7 revealed a stationary thalamic vascular lesion and regression of intraventricular hemorrhage. Hydrocephalus was persistent and two EVD tubes were placed in the bilateral frontal horns.
Fig 5.
The change of mean of indicator “a” in parabolic P-V curve in case 2.
The mean of parameter “a” declined gradually from 0.417 on POD 1 to 0.141 on POD 5.
Fig 6.
Example of different P-V curves in parabolic regression equations with different indicator “a” in one patient from case illustration 2.
The steepest P-V curve was derived from POD 1 with an indicator “a” of 0.417. From left to right, the P-V curve became more and more flat and the indicator “a” in each P-V curves declined from POD 1 to POD 5.
Fig 7.
The progression of brain CT scans in a traumatic brain injury patient (case 3).
Fig 7a. and 7b show that the initial brain CT revealed left fronto-temporal EDH and bilateral frontal and temporal small contusion hemorrhages, and SAH. Fig 7c. and 7d show that the follow-up brain CT after left craniotomy on POD 1 revealed right frontal and temporal contusion hemorrhage progression and right SDH with a midline shift to the left, left frontal and temporal contusion hemorrhages, pneumocephalus, diffuse brain swelling and bilateral slender ventricles. The EVD tube was placed in the left frontal horn.
Fig 8.
The change of mean of indicator “a” in parabolic P-V curve in case 3.
The indicator “a” elevated rapidly from 0.32 to 0.753 during POD 1. After a second craniotomy, the indicator “a” declined to 0.375. The mean of indicator “a” from POD 2 to POD 7 fluctuated between 0.234 and 0.42 and no more rapid elevation of “a” was noted after the second craniotomy.