A rhombus is a quadrilateral with all 4 sides being the same length. For example, look at the chopped-off pyramid on the back of a U.S. one dollar bill. The front face you see under the eye is a trapezoid, since it has 4 sides, and the top parallel with the bottom. A square is one example of a rhombus, but you can have a rhombus that isn't a square.
Causes of Trigeminal Neuralgia. In many cases, the cause of TN is never found. According to the National Institute of Neurological Disorders and Stroke, although anyone can get TN, itâs more common among women than men. Itâs also more common in people over the age of 50, although it can occur at any age.
Causes and Risk Factors. The pain of trigeminal neuralgia is usually caused by pressure on the trigeminal nerve at the base of the brain. The pressure can be result from: 1  A stroke that affects the lower part of the brain, where the trigeminal nerve enters. 2  A tumor that pushes on the nerve.