PARATHYROIDECTOMY - For Treatment of HYPERPLASIA
Dr. Babak Larian of the CENTER for Advanced Parathyroid Surgery specializes in Minimally Invasive Parathyroid Surgery to treat hyperparathyroidism. Treatment of parathyroid hyperplasia is more complicated because, hyperplasia means all of the parathyroid cells in all of the parathyroid glands are over-working. This usually results in each gland working (producing PTH) at a different rate and growing at a different pace (Figure 1).
Treatment involves finding all 4 abnormal gland, removing the largest 3 and deciding how to address the 4th & smallest parathyroid gland. If the smallest gland is small (the size of a normal parathyroid gland or smaller then it only should be biopsied if that is deemed not to damage it. If it is larger then reducing it’s size so that it is roughly the size of a normal parathyroid gland while making sure the blood vessels feeding the 4th gland is safe and functioning; this can be confirmed by doing PTH testing at the end of the procedure several times to make sure the last gland is functioning adequately. As a parathyroid surgery expert, Dr. Larian always conducts an advanced 4 gland assessment in order to provide his patients with the highest cure rate & minimize the risk of permanent hypoparathryoidism.
4 Gland Assessment
In the 1990’s 4 gland assessment was done by looking at all 4 glands and doing a biopsy. However, this was fraught with problems because doing a biopsy was not always able to distinguish between a normal and over functional gland. Additionally, when there is one parathyroid adenoma (a benign tumor in the parathyroid gland) that is overworking, the remaining 3 glands become much less active and shrink and become smaller (Figures 2 & 3); looking for these smaller parathyroids and biopsying them can potentially injure them and ultimately lead to permanent hypoparathyroidism. Since hyperparathyroidism is caused by one or more abnormal glands producing too much PTH, the modern version of 4 gland assessment is to remove the enlarged gland and then look at the physiologic function of the remaining glands by checking how much PTH they are producing & putting into the blood stream; the only accurate way to test PTH levels is by checking the amount in the blood stream (Figures 3 & 4). This is called rapid intra operative PTH testing. So after removal of one gland if the PTH level goes down by more then 50% in 10 minutes then the remaining glands are dormant. If the PTH does NOT go down by 50% then that means one or more of the remaining glands are abnormal and should be investigated.
In case of parathyroid hyperplasia the 4 gland assessment with the help of rapid PTH testing really makes a huge difference; it can not only tell you if you have reduced the number of abnormal parathyroid glands appropriately, but also that the last remaining gland is working adequately to minimize the risk of permanent hypoparathyroidism.
Surgical Steps
1. PTH level testing in pre-surgery unit while placing the IV
2. Patient comes into the operating room and lays flat on the bed
3. Place Breathing tube
4. Local anesthetic given
5. Skin cleaned & sterilized
6. Surgery
A. Incision 1.5 to 2 cm (less then an inch)
B. Expose the sternohyoid muscle (covering the thyroid & trachea)
C. Separating away the thin muscles from over the thyroid (not cutting the muscle) on the side where scans showed the abnormal parathyroid gland.
D. Find the recurrent laryngeal nerve (RLN) deep to the thyroid
E. Follow the RLN, and protect the nerve
F. If no enlarged parathyroid gland is seen on the localization scans before surgery, then during surgery all 4 parathyroid glands & the small blood vessels feeding them must be identified
G. Get a pre-excision blood PTH level. Biopsy the smallest parathyroid (of the 4) & remove the larger parathyroid on the same side (right in this case). It is preferred to mark the smallest parathyroid with a titanium clip, just in case this parathyroid needs to be operated on in the future
H. Remove the 2 larger parathyroids on the opposite side (left in this case)
I. Check another PTH level at 5, 10 & 15 minutes to make sure it goes down by more than 50%, into the normal range & stays low. And also to see the 4th gland that was just biopsied is functioning adequately to maintain appropriate calcium levels for the person after surgery. THIS IS CRUCIAL BECAUSE THEN YOUR SURGEON KNOWS THAT YOU HAVE AN APPROPRIATE AMOUNT OF PARATHYROID GLAND LEFT BEHIND
J. Examine the area of surgery to make sure there is no bleeding from the small blood vessels. Then bring the muscles over the thyroid together again
K. Suture the skin close in multiple layers with absorbable sutures that are under the surface
L. Place a steri-strip (medical grade tape) on the incision for added protection
M. Fully awaken the patient and go to recovery room
N. Remain in the recovery room until fully awake
O. Release to go home usually after an hour
Operative Time Can Be Very Short or Long
The length of time for parathyroidectomy for hyperplasia varies a lot, although usually is around an hour. Some times it can be much longer if the person has a large thyroid goiter, large nodules, or has inflammation in the area due to Hashimoto’s Thryoiditis. Some people have parathyroid glands that are in unusual locations and need to be gently and cautiously found.
Almost all patients are sent home within an hour or two of the operation. Everyone is placed on calcium, vitamin D & magnesium supplements to prevent low calcium levels.
Low Calcium Levels After Surgery
In all patients who have parathyroid surgery for hyperplasia, the remaining parathyroid gland will be slightly in shock, and will not be functioning properly immediately after surgery (how much less the last remaining parathyroid is working can be checked during surgery based on the degree of drop of PTH level after removal of parathyroids). This is usually temporary and can cause the blood calcium level to drop below normal (called hypocalcemia).
Symptoms of Hypocalcemia
- Numbness and tingling around the lips, in both of your hands or fingertips, or soles of both of your feet.
- Muscle cramps that last
- Some patients experience a “crawling” sensation in the skin
- Rarely severe unusual headaches
These symptoms appear between 24 and 48 hours after surgery.
Hypocalcemia Prevention
Prior to the surgery we will give you specific instructions (table below) as to how much calcium and vitamin D replacement you will need to take after surgery. This is dependent on your pre surgery calcium levels and the number of glands that are diseased, as well as how much the PTH drops during surgery. Some may need just Citracal Petites pills if the drop in PTH is in the normal range. If the drop is dramatic and below normal levels due to parathyroid glands being in shock then the person may need Calcium & Rocalcitrol. Dr. Larian will let you know what is appropriate for you after surgery.
Hypocalcemia Symptom Treatment
Patients with calciums of less than 14 prior to surgery: at any point if symptoms develop, you should take 8 extra Citracal Petites pills and contact Dr. Larian ASAP.
After Surgery Blood Tests
(You will be given prescriptions for these tests) One month & 6 months after surgery: Calcium, PTH & Vitamin D Levels. And then yearly thereafter.
(You will be given prescriptions for these tests)
- One month & 6 months after surgery: Calcium, PTH & Vitamin D Levels.
- And then yearly thereafter.
If you are considering minimally invasive parathyroidectomy, schedule a consultation with Dr. Larian or give us a call at 310.461.0300 today!