A 7-year-old girl entered the office. Eight months prior, she had fallen out of a tree and subsequently began experiencing visual disturbances. Shortly thereafter she was declared legally blind. Numerous visits to a local children’s hospital with multiple MRI and CT scans performed resulted in no clear reason found for her vision problems. A diagnosis of idiopathic blindness was given, which essentially means they had no idea of the cause of her symptoms.
Medications were offered as a possible treatment, but the prescribing physician said their effectiveness would be a longshot at best, and the potential side effects were very serious including increased chance of developing cancer. The parents were not willing to risk these potential side effects until a conclusive diagnosis was established.
The hardware we designed limited patient movement so we were able to take accurate 3D x-rays of this patient. After taking the 3D x-ray Images. By viewing these images for the first time in all three dimensions, multiple diagnoses were found.
The spatial information present in the 3D image revealed a fracture of the C2 dens from the trauma, a diagnosis that is hard to make from traditional imaging techniques as they are viewed in only two planes. The C2 dens is located in the center of the skull and suffers from being obscured from view due to superimposed structures. The location of this fracture is highlighted by item A in the 2D x-ray image shown in Figure 1.
Furthermore, a congenital anomaly of the posterior arch of the atlas vertebra was also revealed and can be seen in item A of Figure 2. The scope of this anomaly was fully discovered while viewing it in 3D. The posterior arch of the atlas had inverted toward the brainstem, resulting in pressure to the mesencephalon region of the brainstem, a region that houses the superior colliculus, a structure vital to vision and often referred to as the visual cortex.
It was determined that the fall induced a C1 displacement which, in combination with the congenital malformation, caused the vertebra to apply pressure to the visual cortex, resulting in the patient’s ailments.
Knowing this information allowed for appropriate treatment to be rendered. The patient was beside herself with joy on the follow up visit. The entire office was brightened that day as she could be heard throughout, joyfully yelling for people to hold up fingers because she was going to count them. Patient has fully recovered and is able to see, thanks to 3D x-ray images.
2D x-ray image of image pair used for 3D x-ray image generation. It is difficult to see, but the area highlighted by A shows a small fracture that was only found when observing in 3D.
2D representation of a 3D x-ray image showing a congenital anomaly of the posterior arch of the atlas vertebra, causing the vertebra to push against the brainstem.