How an M.D. Reads a Head CT
After a Brain Injury

The first imaging study most catastrophic head-injury patients receive is a non-contrast head CT in the emergency department. The scan takes about ten seconds. The radiologist's report is usually one or two paragraphs, often dictated in the middle of a busy overnight shift, and frequently signs off with some version of "no acute intracranial abnormality" or "no acute hemorrhage or mass effect."

That sentence is the one the defense will quote at every deposition and every mediation. The medical-legal job is to put it in context.

What CT is good at

A non-contrast head CT is the appropriate first study after trauma because it is fast and it answers the questions that determine whether a person needs the operating room in the next thirty minutes. The American College of Radiology's Appropriateness Criteria designate CT as the first-line study for acute head trauma for exactly this reason. The questions CT answers well are:

• Is there acute blood inside the skull? Epidural hematoma, subdural hematoma, subarachnoid hemorrhage, intraparenchymal hemorrhage, intraventricular hemorrhage. Fresh blood is hyperdense on CT and shows up bright white.
• Is there a skull fracture? Linear, depressed, basilar. The bone window is excellent for this.
• Is the brain shifting? Midline shift, effaced cisterns, herniation patterns. These findings dictate whether a craniotomy or craniectomy is needed.
• Is there a foreign body or penetrating injury? Bullet fragments, glass, debris.

When a head CT reads "no acute abnormality," what the radiologist has done is rule out the emergencies on that list. They have answered the questions CT can actually answer. That is a useful, important piece of information. It is not, however, a statement about whether the brain is injured.

What CT is bad at

CT detects density differences. The brain is mostly water, soft tissue, and fat, all of which have similar densities. The findings CT misses include:

• Diffuse axonal injury (DAI). When the brain rotates inside the skull during a high-energy crash, the long axonal tracts in the white matter shear at the points where tissue densities change. The damage happens at the cellular level. CT cannot resolve it.
• Microbleeds. Tiny petechial hemorrhages along the corticomedullary junction, the corpus callosum, and the brainstem. The classic radiographic signature of DAI. CT shows them rarely; susceptibility-weighted MRI shows them clearly.
• Subtle contusions. Bruises on the inferior frontal lobes and the anterior temporal lobes — the two regions of the brain that strike the inside of the skull during front-back acceleration. These often look normal on day-one CT and become visible only on follow-up MRI two or three weeks later.
• Hypoxic-ischemic injury. When the brain has been deprived of oxygen for minutes — cardiac arrest, drowning, prolonged hypotension — the damage takes hours or days to declare itself on imaging. The CT in the ER may look fine.

Every one of those findings can cause permanent cognitive, emotional, and vocational impairment. None of them require a hospital admission on day one. All of them are routinely missed when the only imaging is a head CT and the only review is a four-sentence report.

Reading the scan, not just the report

On every catastrophic brain injury case, the firm pulls the actual DICOM images rather than relying on the dictated report. The images are loaded in a standard PACS viewer and reviewed slice by slice, in the bone window, the brain window, and the subdural window. The questions Herb Borroto, M.D., J.D., asks while scrolling the stack are not the same questions an ER radiologist asks at 3 a.m.:

• Is there an asymmetric loss of gray-white differentiation? An early sign of edema that the acute reader rarely flags.
• Are the basal cisterns symmetric, or is there any suggestion of early swelling pushing tissue down?
• Is there a small extra-axial collection along the inner table of the skull that could have been missed in a thin-slice review?
• Is there hyperdensity in any sulcus that could represent subarachnoid blood at the limit of CT resolution?
• Are there any findings in the bone window that don't match the mechanism described in the EMS report — or, conversely, missing findings that should have been there given the mechanism?

Most catastrophic-injury attorneys do not have the training to ask those questions, so they do not. The defense knows that, and writes the opening statement around it.

When the MRI tells the rest of the story

Every catastrophic head injury case in our practice gets an MRI ordered if one has not been done already. The MRI is the diagnostic study; the CT was the triage study. The sequences that matter most in litigation are:

• Susceptibility-weighted imaging (SWI). The most sensitive sequence ever developed for detecting microbleeds. A normal head CT and a positive SWI is the single most common pattern in moderate diffuse axonal injury. If the SWI shows microbleeds along the corpus callosum and the gray-white junction, the case becomes a different case overnight.
• Diffusion tensor imaging (DTI). Maps the integrity of the white-matter tracts. Reduced fractional anisotropy along specific tract regions correlates with specific cognitive deficits. Increasingly admissible in federal and state courts after the standard Daubert analysis.
• FLAIR (fluid-attenuated inversion recovery). The sequence that picks up the late edema and gliosis — the scar tissue the brain forms in response to injury. Especially useful on follow-up imaging three to six months after the injury.
• Diffusion-weighted imaging (DWI). Detects acute ischemic injury within minutes. Critical in anoxic and hypoxic brain injury cases.

When the firm retains a neuroradiologist as a testifying expert, the work product the expert is asked to comment on includes the M.D./J.D. review of the imaging. That review names the structures, the sequences, and the findings — in medical language — before the expert is ever retained. It saves expert hours, it produces a tighter case theory, and it gives the trial team a head start on cross-examining the defense radiologist.

The defense radiologist problem

Defense radiology experts are not the same people as treating radiologists. The treating radiologist reads the imaging in the context of the patient's clinical presentation: the Glasgow Coma Scale, the loss of consciousness, the symptom trajectory. The defense radiologist is hired to read the imaging in isolation, often eighteen months after the fact, with the assignment of minimizing every finding. A microbleed becomes "artifact." A subtle contusion becomes "incidental." A small extra-axial collection becomes "longstanding."

Cross-examining that testimony is not a question of throwing terminology at the witness — the witness has more terminology than anyone else in the room. It is a question of holding the witness to the same standards their own professional society applies in clinical practice. The American Society of Neuroradiology has published positions on the role of advanced imaging in mild TBI evaluation that often directly contradict the conclusions defense radiologists offer in court. The cross-examination starts with those documents.

What this means for a case

If you are reading this because someone you love had a head injury, the practical takeaways are these. First, the ER CT is not the final word. Get the MRI ordered — with the right sequences — and get it done as soon as the patient is medically stable. Second, do not let any insurance adjuster, defense lawyer, or treating provider tell you that a normal CT means a normal brain. Third, save the imaging on disc. The hospital is not required to keep DICOM files forever, and a case built years later will need them.

The way you win a brain injury case is not by being louder than the defense radiologist. It is by reading the scan first — the way a doctor reads it — and building the case from what is actually there.