Cosmetic Flashcards
Normally, how many hair follicles are contained within 1cm3 of scalp?
200
What percent of patients with secondary hyperparathyroidism require parathyroidectomy?
What are the primary theories on the etiology of infraorbital bags?
- Congenitally excess fat.
- Weakening of the orbital septum and attenuation of the orbicularis oculi.
- 3• Weakening of global support resulting in enophthalmos and lower lid pseudoherniation.
- 4•Weakening and descent of the Lockwood suspensory ligament.
What are the indications for parathyroid exploration in patients with asymptomatic or minimally symptomatic hyperparathyroidism?
- Age less than 50
- History of a life-threatening hypercalcemic episode.
- Kidney stones on abdominal X-rays.
- Serum calcium 1mg/mL above the upper limits of normal for the lab.
- Creatinine clearance reduced by 30% or more compared with age-matched normal persons.
- 24-hour urinary calcium excretion >400 mg.
- T-score at lumbar spine, hip, or distal radius less than -2.5. Poor follow-up expected.
- Coexistent illness complicating conservative management.
What percent of cases of primary hyperparathyroidism are due to diffuse hyperplasia?
14-16%.
What percent of cases of primary hyperparathyroidism are due to carcinoma?
3%.
Approximately what percent of hair follicles must be lost before hair loss is noticeable?
30%.
What is the pathophysiology of androgenetic alopecia?
Affected scalp follicles inhibit androgen, causing terminal hairs to convert to vellus hairs.
What is another cause of bone disease in patients with renal failure that should be ruled out prior to parathyroidectomy?
Aluminum bone disease.
What is the most common cause of hair loss in men and women?
Androgenetic alopecia or male pattern baldness.
What is the primary cause of jowls in the elderly patient?
Attenuation of the masseteric cutaneous ligaments.
What are the indications for parathyroidectomy in patients with secondary hyperparathyroidism?
Bone pain (most common indication), intractable pruritus, calcium-phosphate product over 70 despite medical treatment, calciphylaxis, and osteitis fibrosa cystica.
Which cell is most commonly proliferated in diffuse parathyroid hyperplasia?
Chief cell.
What is the pathophysiology behind secondary hyperparathyroidism from chronic renal failure?
Chronic hypocalcemia results from decreased production of 1,25(0H) 2 vitamin D3, bone resistance to PTH, and decreased clearance of PTH and phosphate, resulting in parathyroid hyperplasia and increased levels of PTH.
What is the most common cause of secondary hyperparathyroidism?
Chronic renal failure.
What are the indications for calcium supplementation after thyroid or parathyroid surgery?
Circumoral paresthesias, anxiety, positive Chvostek’s or Trousseau’s sign, tetany, ECG changes, or serum calcium less than 7.1 mL/dL.
What is the significance of elevated preoperative levels of alkaline phosphatase in patients with chronic renal failure undergoing parathyroidectomy?
Correlates with a good chance of amelioration of bone pain after parathyroidectomy.
What are the CNS manifestations of myxedema?
Depression, memory loss, ataxia, frank psychosis, myxedema, and coma.
What is the medical management of secondary hyperparathyroidism?
Dietary phosphate restriction, phosphate binders, calcium and vitamin D supplementation (calcitriol), sodium bicarbonate (for metabolic acidosis), charcoal hemoperfusion (for pruritus), bisphosphonates.
What is the anatomic basis of “hanging columella”?
Excessively high arch of the alae, abnormally extreme curvature of the intermediate and medial crura, or overaggressive surgical removal of the lateral crus and adjacent soft tissue with subsequent cephalic contraction of alar margin.
What is the most common presentation of severe hypercalcemia?
Extreme lethargy.
What disease should be ruled out on all patients with hypercalcemia?
Familial benign hypocalciuric hypercalcemia (FHH).