SAIFEE HOSPITAL

under the auspices of Saifee Hospital Trust Reg no. E-5448 (Bom)

When I fall sick it is HE who cures me

stay fit in a fascinating manner

Nuclear Medicine and RIA

(Radio Immuno Assay)

Nuclear Medicine is a medical specialty that uses safe, painless and cost effective techniques both to image the body and treat diseases. It involves the use of minute quantities of radioactive  substances combines with pharmaceuticals to study the functioning of various organs and to some extent the structure of the anatomy. It is a procedure to gather medical information, which may be otherwise unavailable with the other existing modalities which may require surgery. This detection process allows to disease to be treated early in its course, leading to highly successful prognosis. In all nuclear medicine scan, small amount of radioactive material tagged with suitable radiopharmaceutical is injected either through the IV route or orally or by inhalation into the body. They produce gamma ray emission from the target organ, which is subsequently scanned by a special type of camera called SPECT (Rotating Gamma Camera).

Nuclear Medicine can provide:

• Accurate images that help healthcare professionals to understand the body’s internal organs and tissues.
• Valuable information and measurements of organ and tissue function.
• Therapy to fight diseases.

Nuclear Medicine is an important tool that is:

• Safe: Only small amounts of short-lived radioactive materials are used.
• Effective: It can detect a wide variety of diseases such as cancer, heart diseases, kidney diseases, brain disorders, etc.

 

   

The other alternatives of utilising these radioisotopes are invitro techniques commonly designated as Radioimmunoassay (RIA). As per this method a patients blood /plasma is collected in a vial from which the serum is separated out and tracer antibody tagged with I-125 or cobalt-57 is added to estimate the particular level of hormone, some of the common day to day hormones are T3, T4, TSH, FreeT3, FreeT4, and thyroid antibodies for thyroid function test. Infertility hormones such as FSH, LH, Prolactin, Progesterone, Oestradiol(E2), Oestradiol(E3), Testosterone (Total & Free) tumor markers such as CEA, AFP, PSA, CEA-CA125, CA-15.3,CA-19.9 etc.Invivo Nuclear Medicine scans are HMPAO Brain SPECT, static brain scan, thyroid scan. Lung perfuston / ventilation scan, stress MUGA with NG intervention for LV functions. Stress Thallium myocardial perfusion scan. Gated SPECT tetrofosmin myocardial scan, static and dynamic liver scan, whole body bone scan, DTPA renogram to assess kidney function, DMSA cortical renal scan, Gl bleeding detection scan, Hepatobiliary imaging scan, Ga-67 whole body scan and 1-131 MIBG scan etc., are also performed routinely.

   

   

VARIOUS TESTS CONDUCTED

• Thyroid Function Test :

Thyroid hormones are today universally measured by radioimmunoassay or enzyme immunoassay. There are 3 hormones involved in thyroid function tests. Apart from these hormones, free T3 and T4 assays are carried out to rule out borderline or doubtful case of hypo or hyperthyroidism. Thyroid Antibodies such as antithyroglobulin & antimicrosomal tests are carried out routinely for thyroiditis & Hyperthyroid patient particularly of Grave's disease.

  • -Tri-iodo Tyronine (T3)

  • -Thyroxine (T4)

  • -Thyroid Stimulating Hormone (TSH)

TSH is a pituitary hormone, which through its action on the thyroid gland plays a major role in maintaining normal circulating levels of iodotyronines, i.e. T3 & T4. TSH is controlled by the negative feedback from circulating T4, T3 and by the hypothalamic releasing hormone (TRH).

In hypothyroidism, where there is impaired production of thyroid hormone, the TSH level is typically highly elevated and T3, T4 titres are suppressed to subnormal levels. T3, T4 titres are elevated in thyrotoxicosis, autonomous toxic adenoma (decompensated / compensated), Toxic multinodular goiter etc. In acute/subacute thyroiditis TSH may or may not be increased and T3, T4 are usually increased with the increase of antibody titres (anti h TG or antimicrosomal).

• Parathyroid Function Test

• Bone & Mineral Metabolism

• FSH, LH, Prolactin, Testosterone, DHEA-SO4 :

FSH (Follicle Stimulating Hormone) is secreted by the B-Cell of the anterior pituitary under the control of the gonadotropin releasing hormone produced in the hypothalamus.

In mature females, FSH initiates the growth and development of ovarian follicles. During ovulation, when the follicle is ruptured the follicle now called corpus luteum, secretes oestradiol and progesterone which control the circulating levels of FSH by negative feedback effect on the hypothalamus.

In menopause, with diminished ovarian function, there is a resulting decrease in oestradiol secretion. Due to lack of a negative feedback mechanism i.e. - diminished E2, the circulating FSH levels become increased.

In mature males, FSH is associated with stimulating and maintenance of spermatogenesis test and E2 has the role of providing the negative feedback mechanism to the hypothalamus for controlling the release of FSH. Infertility in males may occur due to hypogonadism as a result of primary testicular failure.

• Haematology

• Prolactin:

Human prolactin is a polypeptide hormone of the anterior pituitary with an essential role in the secretion of milk and has ability to suppress gonadal functions and values is distinctly elevate at birth but decline to adult levels in less than 3 months.

During pregnancy the level climbs steadily to ten or twenty times its former value and decline to normal after delivery, PRL level increases during sleep and reach their lowest a few hours after walking.

• Reproductive Hormones:

• β-HCG (Beta-HCG):

Human chorionic gonadotropin is a two-chain glycoprotein hormone normally, found in blood and urine only during pregnancy. HCG normally reaches level of approximate 2000 mlU/ml. One month after conception a peak of 50.000 or even 1,00,000 mlU/ml is attained in the 3rd month, after which the gradual decline sets in following delivery, HCG levels normally undergoes rapid descent, reaching non-pregnancy concentration (<5-0mlU/ml) some weeks later after the delivery.

Ectopic pregnancies and pregnancy terminating in spontaneous aborting tend to have lower than normal values. In multiple pregnancies higher values are seen.

• Tumor Marker:

  • PSA (Prostatic Specific Antigen):
    Raised PSA has been reported in-patients with prostate cancer, benign prostatic hypertrophy (BPH) and prostatitis. Even low levels of PSA is non-prostatic tissues and for monitoring prostate cancer patients after therapy.

  • CA -125 II (Ovarian Tumor Marker):
    It is an ovarian tumor marker.

  • CA 15-3 (Breast Cancer Tumor Marker):
    CA 15-3 is circulating antigen associated to human mammary tumors. Increased values of CA 15-3 have been observed in patients having breast cancer and decreased levels has been found I women with no evidence of disease.

  • CA 19-9 (Pancreas & Digestive Tract Tumor Marker) : It is a pancreas and digestive tract tumor marker.