MRI PITUITARY /SELLA

What is an MRI Pituitary/Sella?

An MRI Pituitary/Sella uses the principles of Magnetic Resonance Imaging (MRI) – a powerful combination of strong magnetic fields, radio waves, and sophisticated computer processing – to create detailed, cross-sectional images of the pituitary gland and the sella turcica. The sella turcica is a small, saddle-shaped bony compartment in the skull that houses and protects the pituitary gland.

The pituitary gland, often called the "master gland," is a small but critically important endocrine organ that controls many other hormone-producing glands in your body. Because of its small size and complex surrounding anatomy, high-resolution imaging, like that provided by an MRI Pituitary/Sella, is essential for detecting subtle abnormalities that could affect your health. This test allows doctors to visualize the gland itself, its stalk (which connects it to the brain), and adjacent structures like the optic nerves and cavernous sinuses with exceptional clarity.

Types of MRI Pituitary/Sella

Several types of sequences and approaches can be used for an MRI Pituitary/Sella to provide comprehensive information:

MRI Pituitary/Sella without contrast

This involves standard MRI sequences that evaluate the anatomy of the pituitary gland and sella turcica. It can show the size and shape of the gland and detect larger abnormalities.

MRI Pituitary/Sella with contrast

This is very common for pituitary imaging. A pituitary MRI with contrast involves injecting a gadolinium-based contrast agent into a vein. This agent enhances the visibility of blood vessels and certain types of tissues, including most pituitary adenomas (tumors) and areas of inflammation. This helps to:

• Better delineate the borders of a lesion.
• Characterize the lesion (e.g., a solid tumor versus a cyst).
• Detect very small tumors (microadenomas, less than 10mm) that might not be clearly visible without contrast.
• Assess the vascularity of a lesion. Understanding the risks and benefits of contrast is important in these cases.

Dynamic Contrast-Enhanced (DCE) MRI

This technique involves acquiring rapid images before, during, and after the contrast injection. DCE-MRI can provide information about the blood flow (perfusion) and vascularity of pituitary lesions, which can sometimes help in differentiating types of adenomas or assessing treatment response.

Specific Sequences

Radiologists use specific MRI sequences tailored for pituitary imaging. These often include thin-slice acquisitions (to see fine details in a small area) and images taken in different planes (e.g., coronal, sagittal, axial) to fully evaluate the gland and its surroundings.

During the interpretation of your MRI Pituitary/Sella, the radiologist at Cadabams Diagnostics will meticulously assess various parameters and structures:

Pituitary Gland

• Size: Is it normal, enlarged, or small?
• Shape: Is it symmetrical, or is there any bulging or asymmetry?
• Homogeneity: Does the tissue appear uniform, or are there areas of different signal intensity?
• Signal Intensity: The brightness or darkness of the tissue on different MRI sequences.
• Enhancement Pattern: How the gland tissue and any lesions take up the contrast agent (if used). This is crucial for MRI for pituitary tumor diagnosis.

Sella Turcica

• Size and Shape: Is the bony compartment normal, enlarged, or eroded?
• Bony Integrity: Are there any signs of bone destruction or remodeling?
• Is there evidence of "empty sella" (where the sella appears partially or completely filled with cerebrospinal fluid)?

Pituitary Stalk (Infundibulum)

• Position: Is it midline, or is it deviated (pushed to one side)?
• Thickness: Is it normal, thickened, or thinned?
• Enhancement: Does it enhance normally with contrast?

Suprasellar Cistern & Optic Chiasm

• Suprasellar Cistern: The space above the sella, which contains cerebrospinal fluid and the optic chiasm.
• Optic Chiasm: The X-shaped structure where the optic nerves from each eye cross. The radiologist looks for any compression, displacement, or involvement of the optic chiasm by a pituitary lesion, which could explain vision problems.

Cavernous Sinuses

• These are venous channels located on either side of the sella turcica. They contain important cranial nerves and the carotid arteries.
• The radiologist evaluates for any signs of invasion or compression of the cavernous sinuses by a pituitary lesion, which can be a sign of a more extensive tumor.

Presence, Location, Size, and Characteristics of Any Lesions

This is a key focus for MRI for pituitary tumor diagnosis.

• If a lesion (e.g., adenoma, cyst, inflammation) is identified, its precise location (within the pituitary or adjacent to it), size (often categorized as microadenoma if <10mm, or macroadenoma if ≥10mm), relationship to surrounding structures, and imaging characteristics (e.g., solid, cystic, hemorrhagic, enhancement pattern) are carefully described.

There are many specific medical reasons why get an MRI of pituitary gland. An MRI Pituitary/Sella is a cornerstone in the investigation of various conditions:

Investigation of Hormonal Dysfunctions

• Hyperprolactinemia: High levels of prolactin hormone, leading to symptoms like galactorrhea (milky nipple discharge) and irregular periods or infertility.
• Acromegaly or Gigantism: Caused by excess growth hormone.
• Cushing's Disease: Caused by excess ACTH production from a pituitary tumor, leading to high cortisol levels.
• Hypopituitarism: Deficiency of one or more pituitary hormones, requiring hormone replacement.
• Diabetes Insipidus: A condition causing excessive thirst and urination due to problems with antidiuretic hormone (ADH) production or action.

Evaluation of Symptoms Suggestive of Pituitary Pathology

• Unexplained headaches, especially if persistent or associated with other neurological signs.
• Visual disturbances, such as blurred vision, double vision, or loss of peripheral vision (often bitemporal hemianopsia, indicating pressure on the optic chiasm).
• Cranial nerve palsies (weakness or paralysis of muscles controlled by cranial nerves passing near the pituitary).

Suspected Pituitary Tumors or Other Sellar/Parasellar Masses

This is a primary reason, directly related to MRI for pituitary tumor diagnosis. The scan can help identify, locate, and characterize suspected:

• Pituitary adenomas (benign tumors, the most common type)
• Craniopharyngiomas
• Meningiomas
• Cysts (e.g., Rathke's cleft cyst)

Monitoring Known Pituitary Conditions

For patients already diagnosed with a pituitary disorder, regular MRI Pituitary/Sella scans may be needed to monitor:

• The size of a known tumor over time.
• The response to treatment (medical, surgical, or radiotherapy).
• Any recurrence of a tumor after treatment.

Assessment of Congenital Abnormalities

In some cases, an MRI may be used to evaluate suspected congenital (present at birth) abnormalities of the pituitary gland or sella turcica.

Evaluation of Pituitary Apoplexy

This is a rare but serious condition involving sudden bleeding into or impaired blood supply to a pituitary tumor, causing abrupt headache, vision loss, and hormonal dysfunction.

When and Who Needs to Take an MRI Pituitary/Sella?

Your doctor may recommend an MRI Pituitary/Sella if you are experiencing symptoms or have clinical signs suggestive of a pituitary disorder. Understanding why get an MRI of pituitary gland is important for patients. Common reasons and indications include:

• Persistent or Unusual Headaches: Headaches, particularly those that are new, worsening, or have specific characteristics, can sometimes be related to pressure from a pituitary lesion.
• Vision Changes: The pituitary gland is located close to the optic nerves. Any enlargement of the gland (e.g., due to a tumor) can press on these nerves, leading to symptoms like:
  • Peripheral vision loss (often "tunnel vision" or bitemporal hemianopsia)
  • Blurred vision
  • Double vision
• Unexplained Hormonal Imbalances: The pituitary gland produces several crucial hormones. Symptoms of hormonal imbalance can vary widely depending on which hormone is affected and whether its production is too high or too low. Examples include:
  • Irregular menstrual periods or infertility in women
  • Erectile dysfunction or low libido in men
  • Unexplained weight gain or loss
  • Fatigue and weakness
  • Changes in growth (e.g., acromegaly in adults, gigantism in children)
  • Excessive thirst and urination (diabetes insipidus)
  • Milky nipple discharge (galactorrhea) when not pregnant or breastfeeding
• Symptoms of Pituitary Dysfunction: These can be broad and may overlap with hormonal imbalances, including changes in mood, energy levels, and overall well-being.

Patient groups who commonly undergo an MRI Pituitary/Sella include:

• Individuals with suspected pituitary tumors (most commonly adenomas, which are usually benign).
• Patients with known or suspected problems with hormone production, such as excessive prolactin (hyperprolactinemia), growth hormone (acromegaly/gigantism), or ACTH (Cushing's disease), or deficiencies in these or other pituitary hormones (hypopituitarism).
• People experiencing unexplained neurological symptoms that could originate from the pituitary region.
• Patients requiring follow-up for a previously diagnosed pituitary condition or after treatment (e.g., surgery or medication).

Benefits of Taking the Test

The MRI Pituitary/Sella offers significant benefits in diagnosing and managing pituitary disorders:

• Superior Imaging Detail: It provides detailed, high-resolution images of the pituitary gland, sella turcica, and surrounding soft tissue structures, often superior to other imaging modalities like CT scans or X-rays for this specific anatomical region.
• Accurate Diagnosis: It is crucial for the accurate diagnosis of various pituitary disorders, including growths or tumors. This is a key aspect of using MRI for pituitary tumor diagnosis.
• Treatment Planning: The detailed anatomical information obtained from the MRI helps doctors in planning the most appropriate treatment, whether it's surgery (e.g., showing the tumor's relationship to critical structures), medical therapy, or radiation therapy.
• Non-Invasive: The procedure is non-invasive, meaning it does not require surgical incisions.
• No Ionizing Radiation: Unlike X-rays or CT scans, MRI does not use ionizing radiation, making it a safer option, especially if repeat imaging is needed.
• Detection of Small Abnormalities: MRI is highly sensitive and can detect very small abnormalities, such as microadenomas (pituitary tumors less than 1 cm), which might be missed by other imaging techniques. The use of pituitary MRI with contrast further enhances this benefit.
• Assessment of Surrounding Structures: It clearly visualizes adjacent structures like the optic chiasm and cavernous sinuses, helping to determine if a pituitary lesion is affecting these areas.

Illnesses Diagnosed with MRI Pituitary / Sella

An MRI Pituitary/Sella is instrumental in the MRI for pituitary tumor diagnosis and the identification of various other conditions affecting this region, including:

• Pituitary Adenomas: These are the most common tumors of the pituitary gland. They are usually benign (non-cancerous) and are classified by size:
  • Microadenomas: Tumors less than 10 mm in diameter.
  • Macroadenomas: Tumors 10 mm or larger in diameter, which are more likely to cause symptoms by pressing on surrounding structures or by overproducing hormones.
• Craniopharyngioma: Benign tumors that arise near the pituitary gland, often cystic and calcified.
• Meningioma: Tumors that arise from the meninges (the membranes covering the brain and spinal cord) and can occur in the sellar or parasellar region, potentially compressing the pituitary gland.
• Rathke's Cleft Cyst: Benign, fluid-filled cysts that develop from remnants of Rathke's pouch (an embryological structure).
• Empty Sella Syndrome: A condition where the sella turcica is not completely filled with pituitary tissue, often appearing "empty" or filled with cerebrospinal fluid on MRI. It can be primary (no known cause) or secondary (e.g., after surgery, radiation, or infarction of a tumor).
• Hypophysitis: Inflammation of the pituitary gland, which can be autoimmune, granulomatous, or due to other causes. It can mimic a pituitary tumor.
• Pituitary Apoplexy: A medical emergency caused by sudden hemorrhage (bleeding) into or infarction (loss of blood supply) of a pituitary adenoma, leading to rapid enlargement and acute symptoms.
• Metastases to the Pituitary Gland: Rarely, cancers from other parts of the body (e.g., breast, lung) can spread to the pituitary gland.

Proper preparation helps ensure a smooth and effective MRI Pituitary/Sella scan. Here’s what to expect:

Diet

Usually, no specific dietary restrictions are needed for an MRI without contrast. If a contrast agent is planned for your MRI Pituitary/Sella, Cadabams Diagnostics might ask you to fast for a few hours before the scan. Please confirm any dietary instructions with our staff when scheduling your appointment.

Clothing

Wear comfortable, loose-fitting clothing without any metal (e.g., zippers, snaps, buttons, underwire bras, metal in waistbands). You will likely be asked to change into a hospital gown provided by Cadabams Diagnostics to avoid any interference from metallic items.

Medications

You can usually continue taking your regular medications unless specifically advised otherwise by your doctor or our staff. Please inform the MRI technologist of all medications you are currently taking.

Allergies/Conditions

It is crucial to inform the staff at Cadabams Diagnostics before your scan if you:

• Have any allergies, especially to medications, iodine, or previous contrast dyes.
• Have any kidney problems or are on dialysis (important if contrast is planned).
• Are pregnant or suspect you might be pregnant.
• Have any metallic implants, devices, or fragments in your body (e.g., pacemaker, aneurysm clips, cochlear implant, shrapnel).
• Have had any recent surgeries or illnesses.

Arrival Time

Please arrive at Cadabams Diagnostics a bit earlier than your scheduled appointment time to allow for registration and any necessary pre-scan preparations.

Claustrophobia

If you suffer from claustrophobia (fear of enclosed spaces), discuss this with your referring doctor or our MRI staff at Cadabams Diagnostics well in advance. They may suggest strategies to help you cope, or in some cases, a mild sedative might be prescribed by your doctor.

What to Expect (The Scan Environment)

• The MRI machine is a large, cylindrical magnet with a tunnel-like opening.
• You will hear loud knocking or buzzing sounds during the scan. Earplugs or headphones will be provided.
• It is essential to lie very still throughout the procedure to ensure clear images. Even small movements can blur the pictures. The sella turcica MRI what to expect aspect includes understanding this need for stillness.

Pre-requisites

Before undergoing an MRI Pituitary/Sella, the following are usually required:

• Doctor's Referral: A referral or prescription from your doctor detailing the reason for the scan is typically necessary.
• Kidney Function Test Results: If a gadolinium-based contrast agent is anticipated (common for pituitary MRIs, as in a pituitary MRI with contrast), recent kidney function test results (e.g., serum creatinine, eGFR) may be required to ensure it is safe to administer the contrast. Cadabams Diagnostics will advise if this is needed.
• List of Current Medications, Allergies, and Medical History: Provide a comprehensive list to the technologist.
• Prior Relevant Imaging Studies: If you have had previous MRI scans, CT scans, or X-rays of your head or pituitary region, please bring the reports and images (if possible) to your appointment at Cadabams Diagnostics. This can be very helpful for comparison.

Best Time to Take the MRI Pituitary/Sella

For the MRI Pituitary/Sella scan itself, there is generally no specific "best time" of day, nor does it usually need to be timed with specific physiological cycles (like the menstrual cycle for women) unless your doctor gives particular instructions due to the specific hormone being investigated. Scheduling is primarily based on the availability of the MRI scanner at Cadabams Diagnostics and the medical urgency as determined by your referring physician.

Eligibility

Most individuals can safely undergo an MRI Pituitary/Sella. However, there are some contraindications and cautions:

Absolute Contraindications (MRI is generally NOT safe):

• Certain implanted electronic devices that are not MRI-compatible, such as:
  • Older pacemakers or implantable cardioverter-defibrillators (ICDs). (Many newer models are MRI-conditional, but this must be verified).
  • Cochlear implants.
  • Some types of neurostimulators (e.g., for pain or movement disorders).
  • Certain metallic drug infusion pumps.
• Specific metallic foreign bodies, especially if located in or near critical areas like the eyes or brain (e.g., metal shards from an injury, certain older types of brain aneurysm clips).

Relative Contraindications/Cautions (MRI may be possible but requires careful consideration and special protocols):

• Pregnancy: MRI is generally avoided during the first trimester of pregnancy unless absolutely essential. If you are pregnant or suspect you might be, inform your doctor and the MRI staff at Cadabams Diagnostics. Contrast agents are typically avoided throughout pregnancy.
• Severe Kidney Disease: If a pituitary MRI with contrast is planned, patients with severe kidney disease or those on dialysis have a higher risk of developing Nephrogenic Systemic Fibrosis (NSF). Your kidney function will be assessed.
• Significant Claustrophobia: As mentioned, this can make the scan difficult. Options like sedation or an open MRI (if suitable for pituitary imaging and available) may be discussed.
• Weight Exceeding MRI Table Limit: MRI tables have weight limits, which vary by machine.
• Ferromagnetic Surgical Implants: Most modern orthopedic implants (e.g., joint replacements, screws) are made of non-ferromagnetic materials and are MRI-safe. However, it's always best to confirm.

Always discuss your full medical history and any implants with the staff at Cadabams Diagnostics before your MRI Pituitary/Sella scan.

Procedure for Taking an MRI Pituitary/Sella

Understanding the pituitary gland MRI procedure and sella turcica MRI what to expect can help alleviate anxiety. Here's a step-by-step guide to what happens during your MRI Pituitary/Sella at Cadabams Diagnostics:

1. Check-in & Preparation:

   • Upon arrival at Cadabams Diagnostics, you will complete registration and may be asked to fill out a safety questionnaire.
   • You will be asked to change into a hospital gown and remove all metallic objects, including jewelry, watches, hearing aids, dentures (if they contain metal), hairpins, and any clothing with metal. Lockers are usually provided for your belongings.

2. IV Line (if contrast is needed):

   • If your MRI Pituitary/Sella includes contrast (common for assessing the pituitary gland and for suspected tumors), a small intravenous (IV) line will be inserted into a vein in your arm or hand by a qualified nurse or technologist. This is similar to having a blood test.

3. Positioning:

   • You will be asked to lie down on a padded, motorized table that slides into the MRI scanner. You will usually lie on your back.
   • A special device called a "head coil" will be placed gently around your head. This coil helps to capture high-quality images of the pituitary area and is essential for a detailed MRI Pituitary/Sella. It does not touch your face significantly in most designs.

4. Entering the Scanner:

   • Once you are comfortably positioned and the head coil is in place, the technologist will slide the table into the center of the MRI machine, which is shaped like a large doughnut. Your head will be in the middle of the scanner.

5. During the Scan:

   • The MRI technologist will operate the scanner from an adjacent control room. They will be able to see you through a window and communicate with you via an intercom system. You will usually be given a call bell or squeeze ball to alert them if you need assistance.
   • When the MRI scanner starts taking images, it will produce loud, repetitive knocking, thumping, or buzzing sounds. You will be provided with earplugs or headphones (often with music) to help reduce the noise and make you more comfortable.
   • It is crucial to remain very still during each imaging sequence. Even slight movement can blur the images and may require sequences to be repeated, prolonging the scan.
   • The scan consists of several sequences, each lasting a few minutes. The technologist will likely inform you over the intercom when a sequence is starting and how long it might last.
   • If contrast material is being used, it will be injected through the IV line, usually part-way through the scan. You might feel a cool sensation at the injection site or a mild, brief warm flush; this is normal.

6. Duration:

   • A typical MRI Pituitary/Sella scan usually takes between 30 to 60 minutes to complete. The exact duration depends on the number of imaging sequences required and whether contrast material is used.

After the scan is complete, the table will slide out of the scanner. If an IV line was placed, it will be removed. You can then change back into your clothes. Unless you received sedation, you can usually resume your normal activities immediately.

Caution Before Taking the Test

It is vital for your safety and the quality of the MRI Pituitary/Sella scan that you inform the technologist or staff at Cadabams Diagnostics before the scan if any of the following apply to you:

• Possibility of Pregnancy: If you are pregnant or think you might be. MRI is generally avoided in the first trimester, and contrast is usually avoided throughout pregnancy.
• All Metallic Implants, Devices, or Fragments: This includes pacemakers, defibrillators, cochlear implants, aneurysm clips, neurostimulators, artificial heart valves, metallic plates, screws, pins, staples from previous surgeries, or any metal fragments from injury (especially to the eyes).
• History of Kidney Disease or Dialysis: Particularly important if a pituitary MRI with contrast is planned, due to the risk of NSF.
• Allergies: Especially to medications, iodine, or previous MRI/CT contrast agents.
• Claustrophobia or Anxiety: Severe fear of enclosed spaces.
• Any Recent Illnesses or Surgeries:
• Inability to Lie Flat or Still: For the duration of the scan (approximately 30-60 minutes).

Providing accurate information helps ensure your safety and the success of your MRI Pituitary/Sella.