Retinoblastoma

Retinoblastoma

Retinoblastoma is a fast growing malignant tumor of the retina. This cancer mainly affects children under the age of 6 and is more often than not diagnosed in children ages 1-2 years.

Symptoms and signs of Retinoblastoma range from the most apparent sign such as a peculiar appearance (white glow) of the pupil to less specific or common signs such as a red and irritated eye, degeneration of vision, the iris may be a different color in each eye, or stalled growth or delayed maturation. The eyes of some children with Retinoblastoma can become cross-eyed.

Retinoblastoma happens when a cell of a developing retina forms an anomaly and grows out of control and becomes cancerous. This cancer can be a genetic, inherited form or non-genetic, non-inherited form and can affect one or both eyes.

To diagnose a child, an eye examination with dilation of the pupil is needed along with an ultrasound of the eye. A CT scan or MRI of the head should also be done to assess the tumor and the risk of the cancer spreading.

Almost all patients can be cured if the cancer has not extended beyond the eye. In the case of a tumor spreading past the eye, such as the brain, lungs and bones, the possibility of a cure is reduced. The course of action in treating Retinoblastoma will be contingent on each individual case. Options include chemotherapy laser therapy, radioactive plaques, cryotherapy, surgery or a collaboration of any of these treatments.

Craniopharyngioma

(T1 wt coronal-enhanced MRI)

Craniopharyngioma

Craniopharyngioma can be diagnosed at any age, however it is usually found in children and young adults. This type of brain tumor derives from pituitary gland embryonic tissue called Rathke's pouch. The Rathke's pouch begins in the throat area and moves upward to the brain where the tumor develops from the remnants of Rathke's pouch. Craniopharyngiomas are also known as Rathke's pouch tumors, adamantinomas, or hypophyseal duct tumors.

Because Craniopharyngiomas are almost invariably benign, the tumors are not detected until they becomes rather large which then causes symptoms as they start to apply pressure to other parts of the brain surrounding them. Craniopharyngiomas can range from one, to more than four inches in diameter. The symptoms presented by this brain tumor vary depending on where it is and what part of the brain it is pressing on. If it includes the hypothalamus, a person may have drowsiness, weight gain, mood changes and depression, or problems with temperature control. Loss of peripheral vision can occur when pressure is applied on the nerves that regulate vision. If the pituitary stalk or pituitary gland is compressed it can halt production of part of the pituitary hormones causes symptoms such as fatigue, dry skin, unexplained weight gain, irregular periods, delayed puberty, etc.

There are several test that are done to assess whether or not a person has craniopharyngioma. A blood test is performed to check hormone level along with a complete Pituitary Function test to gauge all the major pituitary hormones and a Visual field test to check if there is any compression of the nerves managing vision. An MRI is used to see the size of the tumor and where the pressure is being applied on the brain. Craniopharyngiomas consist of fluid and sometimes calcium which gives it a distinct look. When scanned, this brain tumors unusual appearance helps differentiate it from other pituitary tumors.

If suspected, craniopharyngioma can be treated largely by surgery, however, even with surgery the tumor may not be able to be entirely removed. Sometimes the tumor will have to be treated with radiation combined with surgery to help destroy it.

Mastoiditis

Mastoiditis

(On the left is an MRI axial T1-weighted image with IV contrast which shows Acute Mastoiditis on the left mastoid process)

Mastoiditis is a bacterial infection of the mastoid air cells within the mastoid process which is the bump located behind each ear. In most occurrences, it happens when an ear infection extends to the mucus membrane encompassing the mastoid process and finally reaches the walls of the mastoid bone itself.
If mastoiditis continues and is not treated it can end in hearing loss and bone destruction in the skull. At the present time, the possibility is good for a full recovery if it is treated without any delay otherwise it could lead to worst problems such as facial paralysis, labyrinthitis, meningitis and brain abscess.

There are various bacteria that can cause mastoiditis such as beta-hemolytic streptococci, staphylococci, hemophilus influenzae, gram-negative organisms and pneumococcus (typically in children under the age of six). Mastoiditis is commonly a complication of Chronic and acute otitis media.
Indications of mastoiditis may consist of low-grade fever, edema of the tympanic membrane, dull ache and tenderness in the area of the mastoid process, thick purulent discharge that commonly becomes more prolific possible conductive hearing loss and postauricular erythema and edema. In order to treat mastoiditis, intense parenteral antibiotic therapy is used which can be done intravenous or intramuscular. If the bone has minimal damage, a myringotomy is done to drain the purulent fluid. A simple mastoidectomy would be required if the infection persists or recurs but if the mastoid is habitually inflamed a radial mastectomy would be necessary. With both the simply or radical mastectomy, the patient would still undergo oral antibiotic therapy.

Medullablastoma (MRI)

Medullablastoma

Medullablastoma is a fast- growing tumor of the cerebellum. The cerebellum controls posture, balance and complex motor functions like speech and balance. Tumors found in the cerebellum are called infratentorial tumors. In adults this tumor can usually be found in the body of the cerebellum especially toward the edges. In children, medullablastomas arise most often near the vermis.

There are different types of medullablastomas: classical medullablastoma, large-cell or anaplastic medullablastoma, desmoplastic nodular medullablatoma, melanotic medulloblastoma, medulloblastoma with glial differentiation, medulloblastoma with neuroblastic or neuronal differentiation and medullomyoblastoma. The early signs of this disease are “flu-like” – loss of appetite, irritability and lethargy so at first a Medullablastoma tends to go unnoticed because the signs are so non-specific. The first symptoms in infants may be irritability and increased head size and the first symptoms in older children and adults may be headaches and vomiting upon awakening. The person usually feels better after vomiting but as the tumor continues to grow, the pressure in the brain increases causing their vomiting, headaches and drowsiness to increase. Since Medullablastomas are found in the cerebellum, which controls movement and balance, a common problem with coordination and dizziness arises.

The first course of action a doctor needs to take in making a diagnosis is to get a symptom history of the patient and to run a neurological examination. MRI is the modality performed to identify the presence of a tumor in the brain and is done with and without contrast.

Once the tumor is established as being a medullablastoma, treatment currently consists of surgery to remove as much of the tumor as viable. The person’s doctor will recommend a treatment plan constructed of details that show the risk of the tumor returning. The doctor will also look at the patients age, how much of the tumor persists or spreads after surgery and amount of metastases to verify risk.

The most crucial measure in treating medullablastoma is to take out as much of the tumor as attainable to help ease the cerebrospinal fluid buildup from either swelling or tumor. After surgery, radiation therapy is typically used to treat medullablastoma because there may be some microscopic tumor cells that persist in the adjoining brain tissue. Chemotherapy can be used in children to decrease the risk of tumor cells extending through the spinal fluid. This treatment may not aid adults because their tumors tend to relapse in the cerebellum.

Prognosis of a patient depends upon how well they respond to treatment, which relies on their age, the size and magnitude of the tumor, the amount of the tumor that can be taken out safely and the stage of metastatic disease.

Getting Started in CT/MRI Procedures

Hello,

My name is Rhoda Stanton. This is my second semester of classes towards receiving my certification in MRI. I have worked for the past 9 years at Methodist Sports Medicine/The Orthopedic Specialist in Indianapolis Indiana as a General Diagnostic x-ray technologist. The clinic has recently formed a partnership with CDI and we now have an MRI center in our new facility at our north office. My wish is to someday be able to work in the MRI center.

This should be a really interesting class and I am looking forward to getting started! I am excited to read everyones blogs and I want to wish everyone a great semester.