MR-based brain and cerebrospinal fluid measurement after traumatic brain injury: correlation with neuropsychological outcome

PURPOSE

To determine the magnitude and time course of changes in the volume of brain and intracranial cerebrospinal fluid (CSF) spaces in patients who have sustained traumatic brain injury and to assess the relationship between these findings and long-term cognitive traumatic outcome.

METHODS

Axial intermediate and T2-weighted MR images of 123 patients with traumatic brain injury were quantified using a multispectral segmentation algorithm. Measurements were corrected for differences in age, sex, and head size using a previously reported normative database. Brain morphology was compared across groups formed on the basis of chronicity of injury. Cognitive functioning and severity of injury were statistically correlated with brain measurements.

RESULTS

Time-dependent expansion of CSF spaces and decreases in brain volume were observed. Increases in ventricular CSF volume, particularly in the temporal horns and third ventricle, preceded subsequent changes in total brain and subarachnoid CSF. High and moderate correlation was observed between volume measures and cognitive outcome and injury severity. Particularly strong was the relation between the volume of the left temporal horn and verbal IQ scores.

CONCLUSION

Predictable time-dependent atrophic changes occurring after traumatic brain injury can be quantified using MR volumetric studies. Our results suggest significant contributions by both diffuse and focal mechanisms of injury. In the postacute period (more than 70 days after injury), MR volumetric studies may be predictive of eventual cognitive outcome.

Magnetic resonance identified ventricular dilation in traumatic brain injury: comparison of pre- and postin jury scan and postin jury results

A case study is presented in which a patient received magnetic resonance (MR) imaging of the brain 3 months prior to a severe traumatic brain injury (TBI). The post-TBI MR findings are compared and contrasted with the pre-TBI MR images. The posttraumatic changes demonstrate a significant dilation of the ventricular system which reflects diffuse axonal injury and loss of brain substance. Correspondingly, the neuropsychological studies in this individual reflect global deficits which match the nonspecific, traumatically induced degenerative changes found in the postinjury MR scan. This case study is unique in that specific preinjury MR findings are available for direct comparison and quantitative analysis of TBI-associated changes in brain structure with neuropsychological outcome.

In vivo behaviour of gamma globulin preparations

Metabolic properties of standard gamma globulin (St-GG) and of several gamma globulin (GG) preparations for intravenous use were analyzed in radioactive tracer studies. The in vivo behaviour of St-GG was investigated in 16 probands and found to be comparable to that of normal IgG. The kinetics of the resorption of St-GG from intramuscular deposits, its elimination from the intravascular compartment and from the body were studied in 2 probands. Metabolic properties of GG preparations for intravenous use were compared with those of St-GG in 3-4 probands after simultaneous injection of 125I- and 131I-labelled tracer doses. Important differences in the half-times of intravascular survival, in the rates of catabolism and in the distribution in the body were noticed for most of the preparations for intravenous use except for an improved acid-treated (pH 4) GG, the in vivo behaviour of which was similar to that of St-GG.