12. MNG
⢠There are multiple nodules in thyroid
⢠Progression from diffuse hyperplastic goiter
⢠Can weigh upto 2kg
⢠Mostly euthyroid
⢠More common in FEMALES
⢠They can be : NonToxic & Toxic
⢠Toxic MNG : a hyperfuntioning nodule may develop within a long
standing goiter resulting in hyperthyroidism . The condition called
PLUMMER SYNDROME
13. AETIOPATHOGENESIS
⢠Puberty , pregnancy : demand feedback in TSH level hypertrophy of gland
( physiological goiter)
⢠Endemic : iodine deficiency.
daily requirement : 0.1-0.15 mg
⢠Dyshormonogenesis: familial ; autosomal recessive condition with deficiency of
peroxidase or dehalogenase resulting in sporadic goiters.
⢠Goitrogens : such as cabbage, drugs like sulfonamides , iodides
⢠Previous irradiation to neck
14. GOITROGENS
⢠Environmental
â Cassava root (contains thiocyanate)
â Vegetables cruciferae family (cabbage, cauliflower, brussel sprouts)
â Milk from regions where goitrogens are present in grass
â Others
⢠Drugs
â Iodides
â Amiodarone, aminoglutethemide, Lithium
â Cobalt
â Diiodoquinone
â Ethionamide
â PAS
17. STAGES IN GOITER FORMATION
STIMULATION DIFFUSE HYPERPLASTIC GOITRE
(reversible if stimulation ceases)
MIXED PATTERN with areas of active &
inactive lobules
(as a result of fluctuating stimulation)
Active lobules bcom more vascular &
hyperplastic until hemorrhage occurs,
causing central necrosis .
Necrotic lobules coalesce to
form nodules filled either
wih iodine free colloid or a
mass of new but inactive
follicles
Continual repetition of this
process results in a nodular
goitre
18.
19. PATHOLOGY
⢠GROSS : multilobulated ; cut section has irregular nodule containing
amts of gelatinous colloid.
Regressive changes occur frequently in older lesion which
include areas of hemorrhage, fibrosis, calcification, and cyst changes
⢠MICROSCOPY : follicles of varying size.
area of hemorrhage, hemosiderin-laden macrophages
calcification
20.
21.
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24.
25. CLINICAL FEATURES
⢠Mass effects like dyspnea , dysphagia, hoarseness ,compression to
the great vessels (superior vene cava syndrome).
⢠Cosmetic effects
⢠Mostly euthyroid , may present with hyperthyroidism (toxic MNG)
⢠Hypothyroidic presentations in specific clinical settings.
26.
27.
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31.
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33.
34. INVESTIGATIONS
⢠Thyroid function tests
⢠Ultrasonography (USG)
⢠Fine needle aspiration cytology (FNAC)
⢠Complete blood picture (CBP)
⢠X-ray neck :AP & Lateral view
⢠CT scan : to look for retrosternal extension
⢠Thyroid scan-contains radioactive I
⢠Indirect laryngoscopy : to see vocal cord mobility
35.
36. COMPLICATIONS
⢠Dyspnoea / dysphagia
⢠Secondary thyrotoxicosis
⢠Calcification of nodules
⢠Degeneration of nodules
⢠Hemorrhage into nodules
⢠Malignant transformation (follicular/papillary)- 5%
⢠Cosmetic disfigurement
37. TREATMENT
⢠In the early stages a hyperplastic goiter may regress if thyroxine is given in
a dose of 0.15-0.2 mg daily for few months.
⢠Although the nodular stage is irreversible , more than half of benign
nodules will regress in size over years.
⢠Most of the MNG are asymptomatic and do not require operation.
⢠Operation may be indicated on cosmetic grounds, for pressure symptoms,
or in response to patient anxiety.
⢠Retrosternal extension is an indication for thyroidectomy.
38. ⢠When entire gland Is involved â total thyroidectomy is better
⢠Subtotal thyroidectomy is done depending on the amt of gland involved, location
8gms of thyroid tissue is retained in each lateral lobe
⢠often partial thyroidectomy or Harley dunhill operation (one lateral lobe + isthmus+ opp
side subtotal or partial)
⢠Reoperation for recurrent nodular goiter is more difficult and hazardous and for this
reason, total thyroidectomy is favoured in younger patients.
⢠Total lobectomy and total thyroidectomy have additional advantage of being therapeutic
for incidental carcinomas.
⢠There is some evidence that radioactive iodine may reduce size of recurrent nodular
goiter after previous subtotal resection and in some circumstances it is safer alternative
than reoperation.
39. ⢠Incision : a gently curved skin crease incision made between the notch of thyroid
cartilage and suprasternal notch- KOCHERS
⢠Superior thyroid artery ligated
Inferior thyroid artery are not routinely ligated to
preserve Parathyroid blood supply.
40. POST OP COMPLICATIONS
⢠Bleeding
⢠infection
⢠Temporary permanent loss of voice
⢠Temppermanent hypocalcemia
⢠Vocal cord paralysis
⢠Need for life long thyroid supplements like L-thyroxine
41. PREVENTION
⢠Use of iodised salt
⢠At puberty : 0.1 mg or 0.2 mg thyroxine
⢠Reduce the use of goitrogens
42.
43. EXAMINATION OF A THYROID SWELLING
⢠INSPECTION : by Pizilloâs method
size, shape and location and borders, surface
look for redness, scar, dialated vein pulsation, sinuses.
⢠Palpation : Laheyâs method for palpation of deep surface
Crileâs method for small nodules
measure size, shape, consistency, mobility
kochers test for stridor
berryâs sign for carotid pulse
⢠Percussion : Dull note if retrosternal extension
⢠Auscultation: bruit