A pituitary adenoma is generally a benign, slow growing tumor that occurs in the pituitary gland. The pituitary gland is a small, bean shaped structure that lies at the base of the brain. It has a central role in the regulation of hormones that affect the body such as Adrenocorticotropic hormone (ACTH), Growth hormone (GH), Prolactin, and Thyroid-stimulating hormone (TSH).

Approximately 1 in 1,000 individuals have pituitary adenomas. They are generally not cancerous but may invade nearby structures.  They are classified based on size. A microadenoma is less than 1 cm in diameter whereas a macroadenoma is larger than 1 cm in size.

Based on whether the pituitary adenoma is a hormone-producing or hormone-inactive tumor, the patient will present with different symptoms. Hormone-producing tumors will make excessive amounts of an active hormone so symptoms present as a hormonal imbalance. The three most common hormone-producing adenomas are Prolactinomas, Growth hormone-secreting pituitary adenoma, and ACTH-secreting pituitary adenoma.

If the patient has a large hormone-inactive or hormone-producing tumor, it may compress surrounding brain structures due to its size.  Large pituitary tumors may compress the pituitary gland contributing to pituitary failure, which can lead to sexual dysfunction, inadequate body cortisol levels, and hypothyroidism. Other possible presentations relating to compression of brain structures include visual loss, headache, the “stalk effect”, and pituitary apoplexy.  The “stalk effect” is due to the compression of the pituitary stalk, the structure connecting the brain to the pituitary gland, which leads to a mild elevation in the hormone prolactin. Higher levels of prolactin in females can contribute to irregular menstrual cycles. Pituitary apoplexy presents with an abrupt headache and visual loss. It can occur under two different situations. The pituitary adenoma can bleed internally causing a sudden increase in size or the tumor can outgrow its blood supply and the dead tissue will swell.

Pituitary adenomas can be diagnosed based on endocrine function testing, imaging, and visual field testing. Often times, visual problems may be the only symptom present.  Optometrists and ophthalmologists should seriously consider the possibility of a pituitary tumor when the patient presents with an unexplained loss of visual field (especially peripheral vision), double vision, or blurred vision as the growth of a pituitary tumor can cause compression on the visual pathway (retina, optic nerve, etc). A delay in diagnosis of a pituitary adenoma may result in permanent loss of vision due to the damage caused by this compression. Endocrine function testing evaluates cortisol, follicle-stimulating hormone, lutenizing hormone, insulin growth factor-1, prolactin, testosterone/estradiol, and thyroid hormone levels. The preferred method of imaging is MRI, which screens for adenomas larger than 4 mm.

Treatment for pituitary adenomas depends on the presence of hormone production, size of the tumor, invasion of the tumor into surrounding structures, and the age and health of the patient. Drug therapy is used to treat hormone-producing tumors. For example, bromocriptine and cabergoline are used to treat tumors secreting prolactin because these medications decrease prolactin levels and tumor size. Pituitary adenomas that require surgery are usually minimally invasive techniques, where the tumor is removed through the nose.  On the other hand, radiation therapy involves high doses of radiation being delivered to the tumor. It is a treatment utilized for pituitary adenomas that cannot be controlled by drug therapy or surgical intervention. Patients have the best outlook when the entire tumor can be removed.

Epidural block has become a popular method of pain management during labor. However, questions persist regarding its safety and effects on mother and baby. Epidural anesthesia is a regional anesthesia, which means it blocks pain from a specific region in the body. The goal of a labor epidural is to block pain impulses from lower spinal segments that can result in decreased feeling in the abdominal and pelvic area. Optimally, this decreases the pain experienced during contractions and labor; however, it allows the patient to retain enough feeling to push the baby out when full cervical dilation is reached.

A combination of medicines is commonly used in epidural anesthesia. These include local anesthetics such as bupivicane, marcaine, or lidocaine, to numb the area; opioids such as fentanyl, or morphine, to decrease pain sensation; and other medication such as epinephrine type drugs that can be used to stabilize the mother’s blood pressure.

Although an epidural may be beneficial due to decreases in labor pain, there are associated risks as well. Maternal side effects can include pain at the spinal injection site as well as leakage of spinal fluid than can cause severe headaches (“spinal headache”) that may require additional treatment.Epidural anesthesia may slow the labor and increase the use of operative delivery techniques such as cesarean section, forceps, or vacuum extraction.

If medical malpractice occurs during placement and management of epidural anesthesia, injury to the newborn may result. After epidural placement, the patient may sustain a drop in blood pressure. The drop in maternal blood pressure may decrease the amount of blood travelling across the placenta and lead to a decrease in blood, oxygen, and nutrients reaching the baby. If the baby was adversely affected by an epidural, there may be abnormal changes in the fetal heart rate pattern.

Medical malpractice may occur in the context of failing to properly manage maternal hypotension (low blood pressure). Decelerations or other non-reassuring patterns in the fetal heart rate can indicate impending damage to the newborn. It is essential that these complications are managed in a timely fashion with appropriate medical intervention to avoid brain injury to the baby from oxygen deprivation.

For example, if the mother’s blood pressure decreases significantly from the epidural, medications can be given to mitigate this effect and raise the blood pressure. By raising the maternal blood pressure, proper placental blood flow is restored or maintained and the baby will be less likely to suffer injury. In addition, oxygen may be administered to the mother during the labor epidural. This can increase the amount of oxygen in the maternal blood, and thereby increase the amount of oxygen in the blood that reaches the baby. This will also serve to decrease the likelihood of fetal injury.

Medical malpractice may occur when maternal blood pressure drops too low causing less oxygen and nutrients to reach the fetus. The baby can suffer permanent brain injury from lack of oxygen. This can manifest as seizures, cerebral palsy, or developmental delay.

Lumbar puncture is a procedure performed in the lower back area, where a needle is inserted between two vertebrae to remove a sample of cerebrospinal fluid (CSF). The patient flexes his/her back to widen the spaces between the vertebrae so it is easier for the physician to access the region. The back is washed with antiseptic soap or iodine and covered with a sterile sheet. A local anesthetic is used to numb the area and then a thin hollow needle is inserted through the spinal membrane and into the spinal canal. During this portion of the procedure, the patient generally feels pressure. The CSF pressure is measured, a small amount of fluid is removed, and the pressure is measured again. The needle is removed and the site is bandaged. The total procedure takes about 45 minutes.

Lumbar puncture is used to collect CSF for analysis to help in diagnosing conditions such as subarachnoid hemorrhage (typically caused by ruptured aneurysm or traumatic brain injury), meningitis (inflammation of the membranes around the brain), and cancers of the brain or spinal cord. Lumbar Puncture may also be utilized to inject anesthetic medications, chemotherapeutic drugs, contrast material, or radioactive substances into CSF.

Lumbar Puncture may be used to identify increased or decreased CSF pressure.  Increased CSF pressure can be caused by increased intracranial pressure as is seen with traumatic brain injury, ruptured aneurysm, and sometimes hydrocephalus. On the other hand, decreased CSF pressure can be caused by spinal cord tumor, shock, fainting, or diabetic coma.  Normal CSF appears clear and colorless. When an infection is present, the CSF may look cloudy and be yellow or pink in color. Infection may be suspected if there is an increased level of white blood cells and/or protein. Increased CSF glucose indicates hyperglycemia whereas decreased CSF glucose may reflect hypoglycemia, bacterial or fungal infection, tuberculosis, or meningitis. If tumor cells are detected, the patient may have cancer in the brain, spinal cord, or CSF.  If there are increased gamma globulin levels, the patient may be suffering from multiple sclerosis, neurosyphilis, or Guillan-Barre syndrome. The analysis of the CSF by the lab and the measuring of CSF pressure recorded from the lumbar puncture help in determining a diagnosis in many serious clinical situations.