Aortoiliac Occulsive Disease

This is called Leriche's syndrome. I had never heard of this disease until I recently had a patient that had been diagnosed. This patient had undergone surgery to resolve his condition. It is an atherosclerotic disease of the aorta and possibly but not always both iliac arteries. The main symptoms include: claudication of buttocks, thighs, fatigue in the lowers limbs, inablility to maintain a penile erection. It was first discovered in 1814 by a man named Robert Graham. But it was named for a French surgeon, Rene' Leriche, who first treated the conditon of a 30 year man. Treatment can be done with surgery by an aortoiliac bypass graft or an axillofemoral and femoral-femoral bypass, depending on the severity of the disease.

Aortic Dissection

Aortic dissection is a tear in the wall of the vessel causing blood to flow between the layers of the aorta. Blood vessels have three layers of tissue starting from the inner layer that is closest to the blood and go to the outer layer. A tear can begin in the inner layer of aorta, called the intima, and the blood will fill into the next layer, called the media, and possibly the outer layer called the adventitia. There can also be a complete ruture of the aorta, where blood is spilling out into the body cavity. A dissection increase in length along the aorta. If the dissection goes in the direction of blood flow toward the iliac bifurcation, it is called an anterograde dissection. If the dissection goes against the blood and back toward the heart, it is called a retrograde dissection. There are also different classifications of aortic dissection depending upon where in the aorta the dissection occurred. An aortic dissection is a medical emergency. It can be caused by hypertension, connective tissue disorders, stenosis of the aortic valves, and chest trauma. 72 -80% of patients with an aortic dissection have a history of high blood pressure. The majority of patients will have severe stabbing chest pain with a aortic dissection. This is sometimes confused with the signs of a heart attack. Surgery is usually the solution for an acute dissection. Patient who have a dissetion and are also having high blood pressure should be given medication to keep their blood pressure under control and not further complicate the dissection.

The above picture MRI reconstruction of of the aorta and it's branches down to the kidneys. You can see the dissection in the arch.

Hemothorax

A hemothorax is something that occurs when an accumulation of blood collects in the pleural cavity. A rupture in the lining that covers the lungs allows blood to fill into the space. It is generally caused by some sort of trauma to the chest cavity. A patient with a hemothorax will have rapid, difficult breathing, cyanosis, and decreased breath sound on the affected side of the chest. This person could also have a rapid heart beat, low blood pressure, and cool,clammy skin. A persistant hemothorax can put pressure on the mediastinum and the trachea; effecting the heart's ability and causing trachea deviation. To relieve the hemothorax, a patient will generally be given a chest tube to remove the blood from the chest. Nurses caring for these patients must keep a close eye on the patient's chest tube to make sure that the blood is not clotting in the chest and in or around the chest tube, which would cause further problems such as infection.

Dissections

I had one of my radiologist tell me one time that he would NEVER go see a chiropractor. He told me how he had read an MRA of the carotids on a patient that had a dissection of her vertebral and carotid arteries from visiting a chiropractor and the doctor had twisted the patient's head the "crack her neck" because she was having neck pain and headaches. I told my radiologist that was telling the story that I would have just stuck with the headaches.

Dissections of the carotid arteries are caused by trauma to the head and/or neck area. A tear forms in the inner lining of the artery and blood begins to fill between the internal and external linings of the artery. This can then cause stenosis or even complete occlusion of the artey. Some patients will not have any symptoms after a carotid dissection. Others can have headaches, neck pain and possibly a CVA. Treatment includes observation of the patient and anticoagulants to prevent a blood clot from forming at the area of the dissection. The patient may also have to undergo surgery a stent or carotid artery ligation.

The image above from Medscape.com shows an angiogram of the Rt carotid artey with an occlusion of the Rt internal carotid artery where the dissection occurred. This occlusion also caused a CVA which is shown in the diffusion weighted MRI image on the left.

Goiters

This week I decided to research goiters for my pathology blog. I have never seen any one with a goiter, but I have had a few patients tell me that they have has surgery to remove a goiter.

A goiter is an enlargement of the tyroid gland in the throat. The most common cause for this enlargement is from a defect hormone synthesis which causes in increase of the Thyroid Stimulating Hormone (TSH). TSH comes from the pituitary gland in the brain. The increase in TSH causes the thyroid to grow. Other cause for a goiter could be malignancy or even a diet deficient of iodine. But the one of the website where I was reading says that this is rare because our diets are sufficient in supplying the iodine we need to prevent this.

Treatment for a goiter can sometimes be taken care of by just taking a pill, which stop the TSH and decrease the size of the thyroid. But as the goiter grows it can begin to cause problems for patients; because it can be compressing structures in the neck, such as the trachea and the esophagus and even some blood vessels. These patients would need to have surgery to remove the goiter to keep it from compressing these organs and causing major damage.

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.

Introduction

Hi! My name is Brooke. This is the start of a new semester and my CT/MRI pathology blog.

Pathology is probably the coolest thing that I like about my job. I am always getting online at work to Google a different diagnosis to find out more about it. This also helps me learn more about my patient and what they might be experiencing. This semester will help me learn more about what types of pathologies look like on my MRI exams.

Have a great semester everyone!