Abnormal asymmetry correlates with abnormal enlargement in a patient with chronic moderate traumatic brain injury.

Aim: Recent studies found patients with chronic, mild or moderate traumatic brain injury had more regions of enlargement than atrophy. There is little research discussing brain volume enlargement, asymmetry and TBI. Materials & methods: In this report, we describe a 40-year-old man who suffered a left cerebral hemorrhage resulting in a moderate TBI, suggesting greater forces on the left side of his brain. NeuroQuant® brain volumetric analyses of his MRI obtained 1.7 years post injury showed left cerebral white matter atrophy but right gray matter abnormal enlargement. Abnormal asymmetry of multiple regions (R >L) was confirmed by NeuroGage® asymmetry analyses. Discussion: The findings suggested that abnormal brain volume enlargement was due to hyperactivity and hypertrophy of less-injured brain regions as a compensatory response to more-injured regions.

Updated Review of the Evidence Supporting the Medical and Legal Use of NeuroQuant® and NeuroGage® in Patients With Traumatic Brain Injury.

Over 40 years of research have shown that traumatic brain injury affects brain volume. However, technical and practical limitations made it difficult to detect brain volume abnormalities in patients suffering from chronic effects of mild or moderate traumatic brain injury. This situation improved in 2006 with the FDA clearance of NeuroQuant®, a commercially available, computer-automated software program for measuring MRI brain volume in human subjects. More recent strides were made with the introduction of NeuroGage®, commercially available software that is based on NeuroQuant® and extends its utility in several ways. Studies using these and similar methods have found that most patients with chronic mild or moderate traumatic brain injury have brain volume abnormalities, and several of these studies found-surprisingly-more abnormal enlargement than atrophy. More generally, 102 peer-reviewed studies have supported the reliability and validity of NeuroQuant® and NeuroGage®. Furthermore, this updated version of a previous review addresses whether NeuroQuant® and NeuroGage® meet the Daubert standard for admissibility in court. It concludes that NeuroQuant® and NeuroGage® meet the Daubert standard based on their reliability, validity, and objectivity. Due to the improvements in technology over the years, these brain volumetric techniques are practical and readily available for clinical or forensic use, and thus they are important tools for detecting signs of brain injury.

Journey to the other side of the brain: asymmetry in patients with chronic mild or moderate traumatic brain injury.

Aim: Patients with chronic mild or moderate traumatic brain injury have some regions of brain atrophy (including cerebral white matter) but even more regions of abnormal brain enlargement (including other cerebral regions). Hypothesis: Ipsilateral injury and atrophy cause the eventual development of contralateral compensatory hypertrophy. Materials & methods: 50 patients with mild or moderate traumatic brain injury were compared to 80 normal controls (n = 80) with respect to MRI brain volume asymmetry. Asymmetry-based correlations were used to test the primary hypothesis. Results: The group of patients had multiple regions of abnormal asymmetry. Conclusion: The correlational analyses supported the conclusion that acute injury to ipsilateral cerebral white matter regions caused atrophy, leading eventually to abnormal enlargement of contralateral regions due to compensatory hypertrophy.

Patients with chronic mild or moderate traumatic brain injury have abnormal brain enlargement.

Introduction: Much less is known about brain volume abnormalities in patients with chronic mild or moderate traumatic brain injury (TBI) compared with patients with more severe injury. Commercially available software methods including NeuroQuant® are being used increasingly to assess MRI brain volume in patients with TBI.Methods: 50 patients with mild or moderate TBI were compared to the NeuroQuant® normal control database (n = thousands) with respect to MRI brain volume.Results: The patients had many areas of abnormal enlargement and fewer areas of atrophy, including abnormally small cerebral white matter (CWM) limited to the first 10 months after injury. Examination of correlations within the patient group between CWM volume and volumes of the abnormally enlarged regions showed multiple significant negative correlations, indicating that CWM atrophy correlated with enlargement of the other regions.Discussion: The finding of many regions of abnormal brain enlargement was relatively new, although a couple of previous studies of patients with mild TBI found similar but more limited findings. The cause of the abnormal enlargement was unknown, but possibilities included: (1) hyperactivity and hypertrophy; or (2) chronic neuro-inflammation and edema.Abbreviations: ADNI: Alzheimer's Disease Neuroimaging Initiative; CWM: cerebral white matter; GM: cerebral cortical gray matter; ICC: intraclass correlations coefficient; IFT: infratentorial; MRI: magnetic resonance imaging; mTBI: mild TBI; NQ: NeuroQuant®; SCN: subcortical nuclei; t0: time of injury; t1: time of first NeuroQuanted MRI scan after injury; t2: time of second NeuroQuanted MRI scan after injury; TBI: traumatic brain injury; VBR: ventricle-to-brain ratio; WBP: whole-brain parenchyma.

Man Versus Machine Part 2: Comparison of Radiologists' Interpretations and NeuroQuant Measures of Brain Asymmetry and Progressive Atrophy in Patients With Traumatic Brain Injury.

This study is an expanded version of an earlier study, which compared NeuroQuant measures of MRI brain volume with the radiologist's traditional approach in outpatients with mild or moderate traumatic brain injury. NeuroQuant volumetric analyses were compared with the radiologists' interpretations. NeuroQuant found significantly higher rates of atrophy (50.0%), abnormal asymmetry (83.3%), and progressive atrophy (70.0%) than the radiologists (12.5%, 0% and 0%, respectively). Overall, NeuroQuant was more sensitive for detecting at least one sign of atrophy, abnormal asymmetry, or progressive atrophy (95.8%) than the traditional radiologist's approach (12.5%).

Back to the future: estimating pre-injury brain volume in patients with traumatic brain injury.

INTRODUCTION: A recent meta-analysis by Hedman et al. allows for accurate estimation of brain volume changes throughout the life span. Additionally, Tate et al. showed that intracranial volume at a later point in life can be used to estimate reliably brain volume at an earlier point in life. These advancements were combined to create a model which allowed the estimation of brain volume just prior to injury in a group of patients with mild or moderate traumatic brain injury (TBI). This volume estimation model was used in combination with actual measurements of brain volume to test hypotheses about progressive brain volume changes in the patients. METHODS: Twenty six patients with mild or moderate TBI were compared to 20 normal control subjects. NeuroQuant® was used to measure brain MRI volume. Brain volume after the injury (from MRI scans performed at t1 and t2) was compared to brain volume just before the injury (volume estimation at t0) using longitudinal designs. Groups were compared with respect to volume changes in whole brain parenchyma (WBP) and its 3 major subdivisions: cortical gray matter (GM), cerebral white matter (CWM) and subcortical nuclei+infratentorial regions (SCN+IFT). RESULTS: Using the normal control data, the volume estimation model was tested by comparing measured brain volume to estimated brain volume; reliability ranged from good to excellent. During the initial phase after injury (t0-t1), the TBI patients had abnormally rapid atrophy of WBP and CWM, and abnormally rapid enlargement of SCN+IFT. Rates of volume change during t0-t1 correlated with cross-sectional measures of volume change at t1, supporting the internal reliability of the volume estimation model. A logistic regression analysis using the volume change data produced a function which perfectly predicted group membership (TBI patients vs. normal control subjects). CONCLUSIONS: During the first few months after injury, patients with mild or moderate TBI have rapid atrophy of WBP and CWM, and rapid enlargement of SCN+IFT. The magnitude and pattern of the changes in volume may allow for the eventual development of diagnostic tools based on the volume estimation approach.

Man versus machine: comparison of radiologists' interpretations and NeuroQuant® volumetric analyses of brain MRIs in patients with traumatic brain injury.

NeuroQuant® is a recently developed, FDA-approved software program for measuring brain MRI volume in clinical settings. The purpose of this study was to compare NeuroQuant with the radiologist's traditional approach, based on visual inspection, in 20 outpatients with mild or moderate traumatic brain injury (TBI). Each MRI was analyzed with NeuroQuant, and the resulting volumetric analyses were compared with the attending radiologist's interpretation. The radiologist's traditional approach found atrophy in 10.0% of patients; NeuroQuant found atrophy in 50.0% of patients. NeuroQuant was more sensitive for detecting brain atrophy than the traditional radiologist's approach.

Progressive brain atrophy in patients with chronic neuropsychiatric symptoms after mild traumatic brain injury: a preliminary study.

INTRODUCTION: NeuroQuant® is a recently developed, FDA-approved software program for measuring brain MRI volume in clinical settings. The aims of this study were as follows: (1) to examine the test-retest reliability of NeuroQuant®; (2) to test the hypothesis that patients with mild traumatic brain injury (TBI) would have abnormally rapid progressive brain atrophy; and (3) to test the hypothesis that progressive brain atrophy in patients with mild TBI would be associated with vocational outcome. METHODS: Sixteen patients with mild TBI were compared to 20 normal controls. Vocational outcome was assessed with the Glasgow Outcome Scale-Extended (GOSE) and Disability Rating Scale (DRS). RESULTS: NeuroQuant® showed high test-re-test reliability. Patients had abnormally rapid progressive atrophy in several brain regions and the rate of atrophy was associated with inability to return to work. CONCLUSIONS: NeuroQuant®, is a reliable and valid method for assessing the anatomic effects of TBI. Progression of atrophy may continue for years after injury, even in patients with mild TBI.