Transcript Surgical importance of Thyroid Gland

Thyroid and Suprarenal Glands
Ahmed Abdellatif, MD, PhD
Anatomy of Thyroid Gland
Thyroid Gland
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Location
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2 lobes
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Isthmus
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Capsule
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Glandular capsule
Pretracheal fascia
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Development
Blood vessels, nerves & lymphatics
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Important structures & relations
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Recurrent laryngeal n
External laryngeal n
Thyroidae ima artery
Parathyroid glands
Surgical importance
Function
Location
Isthmus lies
Anterior to
tracheal rings
2,3,4
Lobes Normally
extend down to
the level of 6th
tracheal ring.
Muscles Covering the
thyroid.
- Infra-Hyoid
(Strap)Muscles cover
the lobes of the
Thyroid, specifically Sterno-thyroid and
-Sterno-hyoid.
- Sternocleidomastoid
overlaps the strap
muscles.
Development of Thyroid
Q. What is the
embryological
Origin of
Parafollicular &
C cells?
Development of thyroid
What is???
* Pyramidal Lobe.
* Thyroglossal duct
* Thyroglossal cysts
Clinical Examination of Thyroid Gland
Why do you ask the patient to swallow, to test for
thyroid swelling?
http://www.youtube.com/watch?v
=fHR2Tw6DxEg
Fascial coverings of the neck &
Thyroid gland
Vessels and Nerves
Arteries
• Superior Thyroid from Ext. Carotid and
• Inferior Thyroid from thyrocervical trunk of the subclavian
• Thyroidea ima from the brachiocephalic artery or the arch of the aorta.
Veins
• Superior  ends in the internal jugular
• Middle  ends in the internal jugular, and
• Inferior thyroid veins  ends in the brachiocephalic vein.
Lymphatic vessels accompany arteries. Why ???
Nerves from the middle and inferior cervical ganglia of the sympathetic trunk.
Blood Supply
Nerves
Nerves related to the
thyroid gland
•
External laryngeal n. (function
??) & Sup. Thyroid a.
• Recurrent laryngeal n. (function
??) & inf. Thyroid artery.
• Sympathetic
Nerves are subject to injury during
thyroid surgery.
Q. What happens if the external
laryngeal n. is cut?
Q. What happens if the recurrent
laryngeal n. is cut?
Posterior Relations
Surgical importance of Thyroid Gland
During Tracheotomy which part of the thyroid gland
is/should be excised? (http://www.youtube.com/watch?v=d_5eKkwnIRs)
Surgical importance of Thyroid Gland
What layers do you need to cut through to reach thyroid, what
muscles need to be pushed away/cut?
What are the structures at risk?
Parathyroid Glands
Following surgery to remove a massive tumor of the thyroid gland, Mr. Smith started to
complain of;
- Tingling and burning (paresthesias) in fingertips, toes and lips
- Muscle aches and leg cramps
- Twitching (spasms) of muscle, especially around mouth.
- Fatigue
Following clinical exam & investigation he was diagnosed with hypo-parathyroidism ????
Control of Thyroid Hormones
Sign / Symptom
BODY WEIGHT
TEMPERATURE SENSITIVITY
HEART RATE
Hypothyroidism
Weight gain.
Cold intolerance
Bradycardia.
Hyperthyroidism
Weight loss.
Heat intolerance
Tachycardia.
BLOOD PRESSURE
Hypertension/hypotension.
Hypertension.
SEXUAL/REPRODUCTIVE
FUNCTIONING
Infertility.
Loss of libido.
Erectile dysfunction.
Infertility.
Loss of libido.
Erectile dysfunction.
ENERGY LEVELS
Fatigue. Slow and sluggish. Sleepiness.
Fatigue but hyperactive. Cannot sit still.
BOWEL MOVEMENTS
MENTAL STATE
Constipation.
Depression.
Poor memory.
Inability to concentrate.
Diarrhea.
Anxious.
Irritable.
FLUID ACCUMULATION
Leg, hands, eyelid swelling (non-pitting edema)
Myxedema.
Round, puffy face.
pleural effusion and pericardial effusion.
Ankle swelling.
Protruding eyeballs (exopthalmos).
SKIN & HAIR
Dry, pale skin.
Dry, coarse hair.
Hair loss.
Loss of lateral eyebrows.
Warm, sweaty skin
Hair loss.
Redness of the palms.
REFLEXES/ MUSCLES
Delayed relaxation of reflexes.
Overactive reflexes (hyperreflexia).
Tremors.
http://www.healthhype.com/hypothyroidism-vs-hyperthyroidism-differences-in-signs-symptoms.html
Suprarenal Glands
Anatomy of Suprarenal glands
Common disorders of
suprarenal glands
Anatomy of
Suprarenal Glands
Retroperitoneal
Yellowish color.
Superior to & slightly anterior to the
upper pole of each kidney.
Right one is triangular
left is semilunar, larger, and at a higher
level.
T12 level
3-5 cm X 5mm thick, ~2 gms.
Both glands are covered by fat and a
fibrous capsule.
Vessels and Nerves
Arteries
Superior Suprarenal artery, from inferior phrenic a. (which are branches of the aorta)
Middle Suprarenal artery from the aorta, and
Inferior Suprarenal artery from the renal a.
Suprarenal veins
- On the right side opens into the inferior vena cava,
- On the left into the renal vein.
Lymphatics end in the lumbar glands.
Nerves from the celiac and renal plexuses, and from the phrenic and vagus nerves.
Sympathetic fibers supply the medulla.
Blood Supply of Suprarenal
Glands
Suprarenal Hormones
• Sympathetic or Parasympathetic ???
Suprarenal Hormones
Control by 
Zona glomerulosa,
15% of cortex
Zona fasciculata, 75
% of cortex
Zona reticularis,
Deep layer of cortex
Secretes
aldosterone synthase
Secretes the
glucocorticoids
cortisol and
corticosterone, +
small amounts of
adrenal androgens &
estrogens.
secretes the adrenal
androgens dehydroepi-androsterone
(DHEA) and
androstenedione,
small amounts of
estrogens and some
glucocorticoids.
Extracellular fluid
concentrations of
angiotensin II and
potassium
Hypothalamicpituitary axis via
Adreno-corticotropic
hormone (ACTH)
ACTH & cortical
androgenstimulating hormone
Disturbances of Adrenal Cortical
hormones
EXCESS
• 1. Cushing syndrome – excess of cortisol
• 2. Hyperaldosteronism – excess of aldosterone
• 3. Virilization syndrome – excess of androgens
INSUFFICIENCY
• 1. Primary acute adrenocortical insufficiency – adrenal crisis
• 2. Primary chronic adrenocortical insufficiency – Addison
disease
• 3. Secondary adrenocortical insufficiency
Primary Aldosteronism (Conn’s Syndrome)
Tumors of the zona glomerulosa  secretes large amounts of aldosterone  Hypokalemia
Increase in plasma Na concentration.
Increase in extracellular fluid volume and blood volume  Hypertension
Hyperadrenalism-Cushing’s Syndrome
Hypercortisolism can occur from;
(1) Adenomas of:
- Anterior pituitary ↑ ACTH, adrenal hyperplasia and excess cortisol secretion;
Hypothalamus  high levels of corticotropin- releasing hormone (CRH), ↑ ACTH release;
Tumors “ectopic secretion” of ACTH by a tumors,
Adenomas of the adrenal cortex. (low ACTH).
(2) Administration of large doses of exogenous synthetic glucocorticoids for therapeutic uses.
Signs & Symptoms of Cushing’s
- Moon face
- Buffalo torso (Buffalo hump)
- Acne, hirsutism, and purplish striae in the skin
- Hypertension
- Suppressed immune system
- Osteoporosis
Adrenogenital Syndrome
Excessive quantities of androgens that cause intense
masculinizing effects throughout the body.
Female
- Growth of a beard, deeper voice,
- Baldness if she also has the genetic trait,
- Masculine distribution of hair,
- Growth of the clitoris to resemble a penis.
Prepubertal male,
Growth of a beard, deeper voice
Masculine distribution of hair
Rapid development of the sexual organs.
Adult male, difficult to make a diagnosis of adrenogenital
syndrome in the adult male.
In adrenogenital syndrome, the excretion of 17-ketosteroids
in the urine may be 10 - 15 times normal.
Hypoadrenalism-Addison’s Disease
Addison’s disease results from failure of the adrenal
cortices to produce adrenocortical hormones, caused by:
Primary atrophy of the adrenal cortices. In 80 % of the
cases, autoimmune.
Tuberculous destruction of the adrenal glands, or
Invasion of the adrenal cortices by cancer.
Mineralocorticoid Deficiency.
Decreases renal tubular sodium reabsorption  NaCl &
water loss. Hyponatremia, Hyperkalemia.
Glucocorticoid Deficiency.
Impossible to maintain normal blood glucose concentration
between meals.
Addisonian Crisis.
In a person with Addison’s disease, the output of glucocorticoids does not increase
during stress. Acute Hyponatremia, Hyperkalemia, Hypoglycemia, Hypercalcemia
Disturbances of the Adrenal
Medulla
EXCESS
Pheochromocytoma
• Irritability/Nervousness
• Pallor
• Palpitations
• Tachycardia
• Hypertension & Blood pressure spikes
• Severe headache
• Sweating
• Weight loss
INSUFFICIENCY
Congenital absence of adrenal medulla
Rarely results in catecholamine insufficiency, because of sympathetic production of
catecholamines.