Midline Shift is Unrelated to Subjective Pupillary Reactivity Assessment on Admission in Moderate and Severe Traumatic Brain Injury

Abstract

BackgroundThis study aims to determine the relationship between pupillary reactivity, midline shift and basal cistern effacement on brain computed tomography (CT) in moderate-to-severe traumatic brain injury (TBI). All are important diagnostic and prognostic measures, but their relationship is unclear.MethodsA total of 204 patients with moderate-to-severe TBI, documented pupillary reactivity, and archived neuroimaging were included. Extent of midline shift and basal cistern effacement were extracted from admission brain CT. Mean midline shift was calculated for each ordinal category of pupillary reactivity and basal cistern effacement. Sequential Chi-square analysis was used to calculate a threshold midline shift for pupillary abnormalities and basal cistern effacement. Univariable and multiple logistic regression analyses were performed.ResultsPupils were bilaterally reactive in 163 patients, unilaterally reactive in 24, and bilaterally unreactive in 17, with mean midline shift (mm) of 1.96, 3.75, and 2.56, respectively (p = 0.14). Basal cisterns were normal in 118 patients, compressed in 45, and absent in 41, with mean midline shift (mm) of 0.64, 2.97, and 5.93, respectively (p < 0.001). Sequential Chi-square analysis identified a threshold for abnormal pupils at a midline shift of 7–7.25 mm (p = 0.032), compressed basal cisterns at 2 mm (p < 0.001), and completely effaced basal cisterns at 7.5 mm (p < 0.001). Logistic regression revealed no association between midline shift and pupillary reactivity. With effaced basal cisterns, the odds ratio for normal pupils was 0.22 (95% CI 0.08–0.56; p = 0.0016) and for at least one unreactive pupil was 0.061 (95% CI 0.012–0.24; p < 0.001). Basal cistern effacement strongly predicted midline shift (OR 1.27; 95% CI 1.17–1.40; p < 0.001).ConclusionsBasal cistern effacement alone is associated with pupillary reactivity and is closely associated with midline shift. It may represent a uniquely useful neuroimaging marker to guide intervention in traumatic brain injury.

Death after discharge: prognostic model of 1-year mortality in traumatic brain injury patients undergoing decompressive craniectomy

“…Basal cistern effacement is closely associated with pupillary reactivity midline shift. Thus, it can represent a uniquely useful neuroimaging characteristic to guide intervention in TBI [ 32 ]. Our study focused on developing prognostic models of predicting the 1-year mortality of TBI patients undergoing DC.…”

Death After Discharge: Prognostic Model of 1-year Mortality in Traumatic Brain Injury Patients Undergoing Decompressive Craniectomy

“…Basal cistern effacement is closely associated with pupillary reactivity midline shift. Thus, it can represent a uniquely useful neuroimaging characteristic to guide intervention in TBI 32 .…”

Prognosis of the decompressive craniectomy for stroke according to preoperative computed tomography

“…A study of Kouvarellis et al with 141 pediatric cases with traumatic brain injury, resulted in an increase in intracranial pressure in patients with close basal cistern and lower survival rates [23]. Nourallah et al revealed that evaluation of basal cisterns in brain CT was directly related to brain stem pressure independent of other parameters (such as age, midline sp shift) in assessing premorbid findings in traumatic brain injury [24].…”

“…Uncal, parahippocampal, and central transtentorial herniation reflect the pressure effects of a wider range of compartments, and basal cistern pressure can be detected earlier, radiologically [24]. In the literature, radiological signs have been tried to be defined as pre-herniation findings indicative of urgent decompressive craniectomy to help to diagnos and treat brain stem damage that will be developed secondary to malignant MCA infarction.…”