Fractures of the mandible

I decided to research mandible fractures for this blog. Mandible fractures occur mostly from trauma, like an assault or motor vehicle accident.

When I was still an x-ray student, I worked as a tech aid in the CT department a lot. One weekend when I was working, a 17 year old guy was brought in by his father for jaw pain. This guy had gotten in a fight at a party the night before. The exam was a CT Facial bones and head and the tech doing the exam did reconstruction images. You could clearly see three complete fractures of the mandible-two on one side of the body and one on the other. The only thing that was holding this patient's jaw together was the fact that he had braces. This patient then had to go to a plastic surgeon to have surgery.

This is a CT reconstruction image of the facial bones that shows a mandible fracture. There is also a fracture of the maxilla with displacement of the teeth.

Papilledema

Papilledema is swelling of the optic disc caused by an increase in intracranial pressure of the brain. This can occur suddenly within a couple of hours or up to a couple of weeks. Signs of papilledema can be sign by an optometrist through an opthalmoscope. Symptoms are vision loss that starts with just a blind spot a first but will then increase to total blindness if not treated. The patient may also have headaches, nausea, and vomitting. An increase in intracranial pressure can be caused by many things. A brain tumor, a blood clot in the venous sagittal sinus, or a hemoorrage are all possible causes that involved the brain. Chiari malformation of the brain also cause an increase in itracranial pressure. This is when the cerebellar tonsils are pushed through that foramen magnum at the base of the skull. Also, neurological syndrome such as Guillian Barre' and Foster Kennedy syndrome can be a cause for papilledema. Treatment for papilledema varies depending on the cause.

Acromegaly

Acromegaly, also known as gigantism, occurs when the pituitary gland produces too much of the growth hormone. The most common cause for this over production of growth hormone is a pituitary adenoma. A pituitary adenoma is a benign tumor on the pituitary gland that secretes hormones.

Symptoms of acromegaly is soft tissue swelling causing growth in the hand, feet, nose, lips, and ears. Also soft tissue swelling of the internal organs can occur in the heart, kidneys, and vocal cords causing heart failure, kidney failure and deepened voice and slowed speech. Acromegaly also causes protrusion of the brow and mandible. As the pituitary adenoma continues to grow, it will begin to compress surrounding structures in the brain and the optic nerves causing vision loss.

To stop the progression of acromegaly, the patient can have srugery to remove the pituitary adenoma, but usually they will also have to take medication the slow the production of the growth hormone.

The image above left is a sagittal MRI head image showing a pituitary adenoma. The image on the right is a skull x-ray of a patient with acromegaly

Neurofibromatosis Type 2

I was researching pathology about the Internal Auditory Canal when I found this-neurofibromatosis type 2. This is a genetic condition. The type 2 disorder is best diagnosed in 90% of patients with bilateral acoustic neuromas. This is a fast growing mass that usually also affects surrounding nerves. It can also cause lesions in the eye and dcan spread to the meninges and the spinal cord. Patients with this gene defect don't seem to have any symtoms until about middle age. Neurosurgery to removed to tumor from the IAC is just about the only treatment option. This will most likely result in hearing loss.

Hydrocephalus

Hydrocephalus is an abnormality of brain. It also sometimes called water on the brain. A large collection of fluid occurs with in the ventricles of the brain and compresses the brain tissue. In adults, the compression of the brain against the walls of the skull from the collection of the fluid can cause seizures and even mental retardation. Hydrocephalus is more acutely seen in adults than in children because of brian dysfunction. In children and infants, symptoms include an abnormally large head. Since the bones of the skull are not completely fused, hydrocephalus will cause the child head to expand.

Currently, there is no cure for hydrocephalus. In recent years, within the last century, the treatment for hydrocephalus is having a shunt placed with in the brain. A neurosurgeon places the shunt inside the brain so that some of the fluid can be drained from the ventricles in to the blood or into the abdomen.

In MRI, some shunt systems are MR safe to be imaged. But I do know that there are some shunt system that have a valve that regulates the flow of the fluid from the brain. This valve can be affected by MRI magnetic field. If it is absolutely necessary for patients with this type of shunt to undergo MR imaging, a neurosugeon must be on hand ready to take the patient to surgery to reset the valve once the MR exam is complete.