1 - clinical plastic surgery

Summary

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I. Definitions and General Principles

• "Plastikos" is the Greek origin of the word plastic, meaning "to mold," referring to the ability to modify an object's shape without destruction.
• Plastic Surgery is a subspecialty focused on techniques to modify tissues to restore both function and form via reconstructive and aesthetic methods.
• Reconstructive Surgery primarily aims to restore function in congenital or acquired defects, with the restoration of form as a vital but secondary goal.
• Aesthetic (Cosmetic) Surgery involves reshaping normal body structures to improve appearance and self-esteem, where patient satisfaction is the ultimate measure of success.

II. Reconstructive Surgery Scope

• Craniosynostosis is the abnormal fusion of skull suture lines leading to patterns such as frontal bossing or a cone-shaped head.
• Chronic Wounds in adults, particularly in the Philippines, are often related to diabetes (foot ulcers) or cerebrovascular disease (venous/arterial ulcers).

III. Cleft Lip and Palate (CLP)

• Clefting is multifactorial and occurs during the first trimester (organogenesis), influenced by genetics, folate deficiency, toxins, or drugs (e.g., Valium, Dilantin).
• Simonart’s Band is a bridge of soft tissue and skin that is pathognomonic for an Incomplete Cleft Lip.
• Primary Palate refers to structures anterior to the incisive foramen; the Secondary Palate is posterior to the incisive foramen.
• Veau Classification for cleft palate morphlogy:
  1. Veau I: Midline, limited to the soft palate.
  2. Veau II: Extends anteriorly to the posterior hard (secondary) palate.
  3. Veau III: Complete unilateral cleft.
  4. Veau IV: Complete bilateral cleft.
• Submucous Cleft Palate presents as a hallmark triad: bifid uvula, a translucent midline (zona pellucida), and a palpable notch in the posterior hard palate.
• Levator Palatini is arranged vertically in cleft cases; its failure to push the palate against the throat prevents the pronunciation of plosive sounds like /p/, /d/, and /b/.
• Hypernasality (Ngongo) occurs when a Submucous Cleft Palate or late repair causes levator muscle dysfunction.

IV. CLP Treatment Timeline

• The Rule of 10s for lip repair requires: 10 weeks of age, 10 lbs weight, and 10 g/dL Hemoglobin.
• Maxillary Retrusion (Yakmo) is a risk if palate repair is done too early (before 10 months), while speech hypernasality is a risk if done too late (after 12 months).

V. The Reconstructive Ladder

• Secondary Intention is the simplest form of wound closure, where the wound is left open to heal naturally via scar tissue filling the gap.
• Primary Closure involves surgically opposing wound edges using sutures, staples, or tissue adhesives.
• Skin Grafting is the transfer of devascularized tissue from a donor to a recipient site, dependent on the recipient's blood supply for survival.
• Local Tissue Rearrangement (Flap) involves moving uninjured skin immediately surrounding the wound; it has better cosmetic outcomes and lower contracture rates.
• Free Tissue Transfer (Microvascular surgery) is the most complex level, involving the harvest of tissue with its blood supply (artery/vein) for anastomosis at a distant site.

VI. Wound Healing Phases

• Chronic Wounds are defined as persisting for >6 weeks, often caused by Infection with an organism count >10^5/gm of tissue.
• Myofibroblasts are responsible for wound contraction during the proliferation phase, moving at a rate of 0.75–1 mm/day.

VII. Scar Formation & Management

• Hypertrophic Scars stay within the original borders of the injury and usually flatten/improve after 6 months.
• Keloids grow beyond the original injury borders, are genetically predisposed, and are more common in pigmented races (Blacks, Southeast Asians).
• Silicone Gel Treatment (sheets or sticks) is the conservative first-line management for excessive scar formation for at least 2 months.
• Intralesional Steroid Injections are invasive treatments for stubborn or burn-related scars to soften and flatten them.

VIII. Primary Closure Factors & Suture Techniques

• Relaxed Skin Tension Lines (RSTL) are natural wrinkle lines; scars parallel to RSTL are inconspicuous, while perpendicular scars are always visible.
• Smoking should be stopped 1 month before and after elective surgery because nicotine causes peripheral vasoconstriction and poor blood supply.
• Simple Interrupted Suture is the gold standard; it should result in slight wound edge eversion to ensure the scar is level once healed.
• Vertical Mattress Suture is excellent for wound edge eversion but must be removed early to prevent cross-hatching marks.
• Horizontal Mattress Suture is the strongest suture, providing good hemostasis; it is ideal for thick skin on the feet and hands.
• Subcuticular Suture is buried within the dermal layer, leaving only the entrance and exit visible, thus avoiding external suture marks.
• Face Suture Removal should occur between 3-5 days post-op (as early as 2 days for eyelids) to prevent permanent hatch marks.

IX. Skin Grafting Principles

• Plasmatic Imbibition (Serum Inhibition) is the first phase of graft take (24–48 hours) where the graft survives via nutrition diffusion from the wound bed.
• Inosculation is the second phase (after 48 hours) where capillary buds from the bed and graft "kiss" and form loose anastomoses.
• Revascularization is the final phase (day 5–10) where firm vascular anastomoses allow perfusion; dressings are usually not removed until this phase.

X. Wound Bed Preparation & Dressings

• The TIME Concept framework for wound assessment:
  • Tissue Management (Debridement)
  • Infection/Inflammation Control
  • Moisture Balance
  • Edge of Wound (Epithelial advancement).
• Sharp Debridement is the gold standard for removing necrotic tissue (T in TIME).
• Hydrogels provide moisture to dry wounds or exposed bone/tendon to prevent desiccation.
• Hydrocolloids gradually liquefy to allow autolytic debridement of moderately exudative wounds (e.g., abrasions).
• NPWT (Negative Pressure Wound Therapy) uses a suction system to promote angiogenesis, formation of granulation tissue, and shortening of the proliferation phase.

XI. Surgical Flaps and Blood Supply

• Surgical Flaps differ from grafts because they are transferred with their native vascular supply intact.
• Axial Pattern Flaps are based on a named, identified artery (e.g., Median Forehead Flap based on the Supratrochlear Artery).
• Random Pattern Flaps rely on an unidentified blood supply from the subdermal plexus.
• Mathes and Nahai classification for Musculocutaneous Flaps:
  • Type 1: One dominant pedicle (Tensor fascia lata).
  • Type 2: One dominant and minor supplemental supply (Gracilis).
  • Type 3: Two dominant pedicles; either can sustain the flap (Gluteus maximus).
  • Type 4: Multiple segmental vessels (Sartorius).
  • Type 5: One dominant and multiple segmental vessels (Latissimus dorsi).
• TRAM Flap (Transverse Rectus Abdominis Myocutaneous) is a regional flap for breast reconstruction based on the Superior Epigastric Artery.
• Angiosomes are discrete tissue units supplied by a single artery, as discovered by Ian Taylor.

XII. High-Yield Comparisons for Exams

• Reconstructive vs. Aesthetic Surgery: Reconstructive deals with pathologic/congenital deformity; Aesthetic deals with normal tissue enhancement.
• STSG vs. FTSG Contraction: STSG undergoes more secondary contraction (shrinking as it heals); FTSG undergoes more primary contraction (shrinking immediately upon harvest).
• Hypertrophic Scar vs. Keloid: Hypertrophic scars stay within wound borders and stabilize; Keloids grow beyond borders and continue to enlarge indefinitely.
• Graft vs. Flap: A Graft is devascularized and relies on the recipient bed for blood; a Flap maintains its own blood supply.
• Thin STSG vs. Thick STSG: Thin grafts have higher success/take rates but are less durable; Thick grafts are more durable but have higher metabolic demands.
• Veau Class I vs. Class IV: Veau I involves only the soft palate; Veau IV involves bilateral complete clefts of both primary and secondary palates.
• RSTL vs. Langer’s Lines: RSTL are observed in living patients (best for scar planning); Langer’s lines were discovered in cadaveric skin.
• Imbibition vs. Inosculation: Imbibition is initial nutrition via diffusion; Inosculation is the alignment and "kissing" of capillary buds.
• Primary vs. Tertiary Intention: Primary intention closes wounds immediately (fastest healing); Tertiary intention (delayed primary closure) involves debriding and observing before grafting.
• Medial vs. Lateral CLP Repair: In cheiloplasty, the Medial segment is rotated downward while the Lateral segment is advanced medially.
• Mathes/Nahai Type 3 vs. Type 5: Type 3 has two dominant pedicles; Type 5 has one dominant pedicle and multiple segmental ones.
• Maceration vs. Desiccation: Maceration is tissue breakdown from too much moisture; Desiccation is tissue death from a wound bed that is too dry.
• Alginate vs. Hydrogel: Alginates absorb heavy exudate; Hydrogels add moisture to dry beds.
• Type I vs. Type III Collagen: Type III is laid down first during proliferation; Type I is the stronger collagen used in the remodeling/scar maturation phase.

QA

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I. Definitions and General Principles

1. What is the Greek origin and meaning of the word Plastikos? | "To mold"
   Refers to the ability to modify an object's shape without destruction.
2. What is the focus of the subspecialty Plastic Surgery? | Restore function and form
   Uses reconstructive and aesthetic methods.
3. What is the primary aim of Reconstructive Surgery? | Restore function
   Restoration of form is a vital but secondary goal.
4. What is the ultimate measure of success in Aesthetic (Cosmetic) Surgery? | Patient satisfaction
   Involves reshaping normal body structures to improve appearance and self-esteem.

II. Reconstructive Surgery Scope

5. What is the common etiology for Pediatric Reconstruction? | Congenital anomalies
   Examples include clefts and synostoses.
6. What are the common etiologies (3) for Adult Reconstruction? | Trauma, tumor, disease
   Trauma (MVC, falls), tumor extirpation, or chronic disease.
7. What are the key conditions (3) in Pediatric Reconstruction? | Clefts, Synostosis, Romberg
   1) Cleft Lip and Palate
   2) Craniosynostosis
   3) Romberg Syndrome.
8. What are the key conditions (3) in Adult Reconstruction? | Fractures, Breast, Pressure sores
   1) Maxillofacial fractures
   2) Breast reconstruction
   3) Pressure sores.
9. What is the "Joker-like" appearance where the lip extends to the lateral ear tragus called in Pediatric Reconstruction? | Macrostomia
10. When should Breast Reconstruction be offered to cancer patients? | Concurrently with mastectomy
    Should be offered to all cancer patients.
11. What is the definition of Craniosynostosis? | Abnormal skull fusion
    Lead to patterns like frontal bossing or a cone-shaped head.
12. What are common causes of Chronic Wounds in the Philippines? | Diabetes or cerebrovascular disease
    Leads to foot ulcers or venous/arterial ulcers.

III. Cleft Lip and Palate (CLP)

13. When does Clefting occur and what influences it? | First trimester
    Multifactorial; influenced by genetics, folate deficiency, toxins, or drugs.
14. What bridge of soft tissue is pathognomonic for an Incomplete Cleft Lip? | Simonart’s Band
15. What is the anatomical landmark that separates the Primary and Secondary Palate? | Incisive foramen
    Primary is anterior; Secondary is posterior.
16. Enumerate the Veau Classification for cleft palate morphology (4). | Veau I-IV
    1) Veau I: Soft palate
    2) Veau II: Hard palate
    3) Veau III: Unilateral
    4) Veau IV: Bilateral.
17. What is the hallmark triad (3) of a Submucous Cleft Palate? | Bifid uvula, midline notch
    1) Bifid uvula
    2) Translucent midline (zona pellucida)
    3) Palpable hard palate notch.
18. Failure of the Levator Palatini to push the palate prevents the pronunciation of which sounds? | Plosive sounds
    Includes /p/, /d/, and /b/.
19. What causes Hypernasality (Ngongo) in cleft patients? | Levator muscle dysfunction
    Occurs due to Submucous Cleft Palate or late repair.

IV. CLP Treatment Timeline

20. What is the timing and goal of Cleft Lip Repair? | 3–6 Months
    Goal: Restore Orbicularis Oris function for suckling.
21. What is the timing and primary goal of Cleft Palate Repair? | 10–12 Months
    Goal: Achieving normal speech.
22. At what age is VPD Surgery performed to treat Velopharyngeal Insufficiency? | 4–7 Years
    Involves lengthening the palate.
23. What bone source is used for Alveolar Bone Graft between age 7–11? | Iliac Crest Bone
24. When is Orthognathic Surgery performed and what is the sequence? | Skeletal maturity
    Females: 18+; Males: 21+; Jaw surgery must precede rhinoplasty.
25. Enumerate the Rule of 10s for lip repair requirements (3). | Age, Weight, Hemoglobin
    1. 10 weeks old
    2. 10 lbs weight
    3. 10 g/dL Hemoglobin.
26. What condition is risked if Cleft Palate Repair is done before 10 months? | Maxillary Retrusion (Yakmo)

V. The Reconstructive Ladder

27. What is the simplest form of wound closure known as Secondary Intention? | Natural healing
    Wound is left open to heal via scar tissue filling the gap.
28. What does Primary Closure involve? | Surgically opposing edges
    Uses sutures, staples, or tissue adhesives.
29. Survival of a Skin Grafting procedure is dependent on what? | Recipient's blood supply
    Transfer of devascularized tissue from donor.
30. What are the benefits of a Local Tissue Rearrangement (Flap)? | Better aesthetics, lower contracture
    Involves moving uninjured skin immediately surrounding the wound.
31. What is the most complex level of reconstruction involving Free Tissue Transfer? | Microvascular surgery
    Harvesting tissue with its blood supply for anastomosis at a distant site.

VI. Wound Healing Phases

32. What is the dominant cell in the Hemostasis & Inflammation phase (48-72 hours)? | Platelets
33. Which phase (Day 4-21) is characterized by Fibroblasts and Type III Collagen? | Proliferation
34. What occurs during the Tissue Remodeling phase (Day 21-1 Year)? | Type I replaces Type III
    Scar flattens and matures as Type III Collagen is replaced by Type I.
35. How are Chronic Wounds defined regarding duration and bacteria count? | >6 weeks, >10^5 organisms/gm
    Often caused by infection.
36. Which cells are responsible for Wound Contraction during proliferation? | Myofibroblasts
    Move at a rate of 0.75–1 mm/day.

VII. Scar Formation & Management

37. What is the characteristic of Hypertrophic Scars regarding wound borders? | Stay within borders
    Usually flatten or improve after 6 months.
38. Which scars grow beyond the original injury borders and are genetically predisposed in Keloids? | Keloids
39. What is the conservative first-line management for Excessive Scar Formation? | Silicone Gel Treatment
    Sheets or sticks used for at least 2 months.
40. What is an invasive treatment for stubborn or burn-related Scars to soften them? | Intralesional Steroid Injections

VIII. Primary Closure Factors & Suture Techniques

41. Scars parallel to Relaxed Skin Tension Lines (RSTL) have what cosmetic appearance? | Inconspicuous
    While perpendicular scars are always visible.
42. Why should Smoking be stopped 1 month before/after surgery? | Peripheral vasoconstriction
    Causes poor blood supply due to nicotine.
43. What is the gold standard suture and its required edge effect for Simple Interrupted Suture? | Slight wound edge eversion
    Ensures the scar is level once healed.
44. Why must a Vertical Mattress Suture be removed early? | Prevent cross-hatching marks
    Excellent for wound edge eversion.
45. What is the strongest suture ideal for thick skin on Hand and Feet? | Horizontal Mattress Suture
46. Which suture technique avoids external marks by being buried in the Dermal Layer? | Subcuticular Suture
47. What is the timeline for Face Suture Removal? | 3–5 days post-op
    As early as 2 days for eyelids to prevent hatch marks.

IX. Skin Grafting Principles

48. Compare STSG vs. FTSG in terms of composition. | STSG: Partial Dermis; FTSG: Complete Dermis
    Both contain epidermis.
49. Compare STSG vs. FTSG in terms of contraction. | STSG: High Secondary; FTSG: High Primary
    FTSG shrinks immediately; STSG shrinks as it heals.
50. Compare STSG vs. FTSG in terms of engraftment success rate. | STSG: Higher success
    STSG has lower metabolic demand.
51. Which graft type provides the best Aesthetic Outcome? | Full-Thickness (FTSG)
    More durable with less pigmentation.
52. What is the first phase of Graft Take (24-48 hours) called? | Plasmatic Imbibition
    Survival via nutrition diffusion.
53. What is the second phase of Graft Take where capillary buds "kiss"? | Inosculation
54. When does the final phase of graft Revascularization occur? | Day 5–10
    Firm vascular anastomoses allow perfusion.

X. Wound Bed Preparation & Dressings

55. Enumerate the TIME Concept for wound assessment (4). | Tissue, Infection, Moisture, Edge
    1. Tissue 2. Infection 3. Moisture 4. Edge.
56. What is the gold standard for removing Necrotic Tissue? | Sharp Debridement
57. What dressing provides moisture to prevent Desiccation of exposed bone? | Hydrogels
58. What allows Autolytic Debridement of moderately exudative wounds? | Hydrocolloids
59. What therapy uses a suction system to promote Angiogenesis? | NPWT
    Negative Pressure Wound Therapy.

XI. Surgical Flaps and Blood Supply

60. How do Surgical Flaps differ from grafts? | Native vascular supply intact
    Grafts are devascularized.
61. Axial Pattern Flaps are based on what? | Named, identified artery
    Example: Median Forehead Flap (Supratrochlear Artery).
62. What is the blood supply for Random Pattern Flaps? | Subdermal plexus
    Relies on an unidentified blood supply.
63. Enumerate the Mathes and Nahai Classification for Musculocutaneous Flaps (5). | Types 1–5
    1. One dominant
    2. Dominant+Minor
    3. Two dominant
    4. Segmental
    5. Dominant+Segmental.
64. What is the blood supply for a TRAM Flap in breast reconstruction? | Superior Epigastric Artery
65. What are Angiosomes? | Discrete tissue units
    Supplied by a single artery (Ian Taylor).

XII. High-Yield Comparisons for Exams

66. Compare Reconstructive vs. Aesthetic Surgery. | Pathologic vs. Normal
    Reconstructive deals with deformity; Aesthetic deals with enhancement.
67. Compare STSG vs. FTSG Contraction. | STSG: Secondary; FTSG: Primary
    Secondary shrinks during healing; Primary shrinks immediately.
68. Compare Hypertrophic Scar vs. Keloid regarding borders. | Hypertrophic: within; Keloid: beyond
    Hypertrophic scars stabilize; Keloids grow indefinitely.
69. Compare Graft vs. Flap blood supply. | Recipient vs. Native
    Graft relies on recipient bed; Flap has its own supply.
70. Compare Thin vs. Thick STSG success. | Thin: higher take
    Thin STSG has higher success; Thick STSG is more durable.
71. Compare Veau Class I vs. Class IV. | Soft palate vs. Bilateral
    Class I is soft palate only; Class IV is bilateral complete.
72. Compare RSTL vs. Langer’s Lines environment. | Living vs. Cadaveric
    RSTL are observed in living patients.
73. Compare Imbibition vs. Inosculation. | Diffusion vs. Capillary buds
    Imbibition is initial nutrient diffusion; Inosculation is alignment.
74. Compare Primary vs. Tertiary Intention. | Immediate vs. Delayed
    Primary is fastest; Tertiary involves observation before closure.
75. Compare Medial vs. Lateral CLP Repair movement. | Medial: downward; Lateral: advanced
    Rotation vs. Advancement.
76. Compare Mathes/Nahai Type 3 vs. Type 5 pedicles. | Type 3: Two dominant
    Type 5: One dominant plus segmental.
77. Compare Maceration vs. Desiccation causes. | Excess moisture vs. Dryness
    Maceration: breakdown; Desiccation: tissue death.
78. Compare Alginate vs. Hydrogel moisture. | Alginate: absorbs; Hydrogel: adds
    Alginates are for heavy exudate; Hydrogels are for dry beds.
79. Compare Type I vs. Type III Collagen sequence. | Type III: first; Type I: remodeling
    Type I is stronger and marks scar maturation.

2 - Aesthetic Surgery

Summary

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I. General Principles of Aesthetic Surgery

• The primary goal of Aesthetic Surgery (also known as cosmetic surgery) is to reshape normal body structures to improve appearance and self-esteem.
• The most important outcome parameter for Aesthetic Surgery is patient satisfaction, rather than a strictly objective appearance, because beauty and self-esteem are subjective.
• The guiding principles of Aesthetic Surgery are based on the harmony of human proportions, the Vitruvian man, and the Golden ratio.
• Clinical photography for Aesthetic Surgery must be documented before surgery, intraoperatively, immediately post-op, and during the remodeling phase to track the evolution of the patient's appearance.
• In Aesthetic Surgery facial analysis, horizontal thirds divide the face into the upper (hairline to eyebrows), middle (eyebrows to nasal base), and lower (nasal base to chin) segments, which should ideally be equal.
• The vertical facial proportions of Aesthetic Surgery use the medial epicanthus as a landmark; the flare of the nasal ala should ideally align with the medial canthus.

II. Minimally Invasive and Non-Invasive Procedures

• Hyaluronic Acid Fillers are characterized by "G prime" (hardness/viscosity); lower G' is smoother for lips, while higher G' is used for malar (cheek) prominences.
• Calcium Hydroxylapatite (Radiesse) is a filler that stimulates natural collagen growth and is used for lipodystrophy or creating a "chiseled" jawline in men.
• Poly-L Lactic Acid (Sculptra) is an FDA-approved filler specifically for HIV-associated lipodystrophy.
• Ablative Lasers (CO2) are considered the gold standard for improving facial wrinkles but require a longer downtime of 1–2 weeks and carry a risk of hyperpigmentation in Asians (Fitzpatrick type 3+).
• Chemical Peels are categorized into three levels: 1) Superficial (salicylic/glycolic acid), 2) Moderate (TCA), and 3) Deep (Hetter's/Baker-Gordon).
• Dermabrasion involves the mechanical removal of top skin layers to stimulate collagen in the dermal layer; it is used to resurface acne scars with a 7–10 day downtime.
• Microdermabrasion is a suction-based device (often called "diamond peel") that removes dead skin but does not reach the dermis to stimulate collagen.
• Ultherapy and Thermage are non-invasive treatments that use radiofrequency or ultrasound to tighten skin laxity.
• Coolsculpting (Cryotherapy) is a non-invasive procedure that uses focused cooling to target and reduce subcutaneous fat by up to 29%.

III. Facial Danger Zones and Anatomy

• The Superficial Musculo-Aponeurotic System (SMAS) is the muscle-fascial layer of the face that originates as the platysma and terminates superiorly as the galea aponeurotica.
• Injury to the Temporal branch of the Facial Nerve within Facial Danger Zone 2 results in permanent paralysis of the frontalis muscle.
• Sensory deficits in the face after surgery commonly involve injuries to Facial Danger Zones 1, 5, 6, and 7.

IV. Facial Surgical Procedures

• Brow Ptosis is the descent of the eyebrows due to aging; in females, the ideal brow peaks at the lateral third, while in males, it is straight at the supraorbital ridge.
• The Endoscopic Brow Lift is the current gold standard for brow rejuvenation because it uses small incisions hidden in the hair-bearing scalp.
• Dermatochalasis is the presence of excess upper eyelid skin that may disrupt peripheral vision and is a common indication for Blepharoplasty.
• Post-procedure Blepharoplasty care involves cold compress for the first 48 hours to minimize vasodilation, followed by warm compress on day 3 to help absorb hematoma.
• Facelift (Rhytidectomy) techniques that only address subcutaneous skin are abandoned due to high recurrence; successful lifts must address the SMAS layer.
• Asian Rhinoplasty typically focuses on augmentation of the nasal dorsum and tip using medical-grade implants (silicone/Gore-Tex) or autologous rib/ear cartilage.
• A Columellar Strut is a cartilage graft used in Rhinoplasty to provide tripod support and achieve better nasal tip projection.

V. Aesthetic Breast Surgery

• Preoperative screening for Breast Aesthetic Surgery requires a breast MRI if the patient is < 40 years old or a mammogram if ≥ 40 years old to rule out cancer.
• Breast Reduction is indicated for the symptomatic triad of: 1) Upper back pain, 2) Bra strap grooving, and 3) Rashes under the inframammary fold (IMF).
• Poland Syndrome is a congenital condition involving missing or underdeveloped pectoralis major muscles often requiring Breast Augmentation.
• Subglandular Implants (under the gland) require a skin pinch test of at least 2 cm; if the skin is thinner, a Submuscular Implant (under the muscle) is preferred.
• The Inframammary Approach for breast implants is considered the safest with the least complications due to direct visualization of the plane.
• Physiologic Gynecomastia in males is expected in three stages: 1) Neonatal period, 2) Puberty, and 3) Senescence (as testosterone drops and estrogen rises).
• Pathologic Gynecomastia may be drug-induced by substances such as Digitalis, Marijuana (cannabis), Alcohol, Anabolic steroids, Spironolactone, or Cimetidine.
• The Simons Grading Classification is used to assess the severity of Gynecomastia; grades II and higher usually require surgical excision or liposuction.

VI. Body Contouring and Liposuction

• Liposuction (Suction Assisted Lipectomy) is not a weight-loss procedure but a body contouring technique for patients with good skin elasticity.
• The Tumescent Technique in liposuction involves infiltrating dilute lidocaine and epinephrine to reduce blood loss and allow higher safe doses of lidocaine (up to 35 mg/kg).
• An Abdominal Wall Pannus is a redundancy of skin and fat hanging over the pubic area, often requiring a Panniculectomy.
• Abdominoplasty (Tummy Tuck) involves the maximal removal of excess skin, tightening of the underlying abdominal fascia, and transposition of the umbilicus.
• The Fleur-de-lis Abdominoplasty is specifically designed for massive weight loss patients to correct both horizontal and vertical skin excess, resulting in a midline vertical scar.
• Autologous Fat Grafting (e.g., "Mommy Makeover") involves harvesting fat from one area via liposuction and transferring it to another, such as the buttocks.

VII. High-Yield Distinctions for Exams

• Contrast Static vs. Dynamic Lines: Static lines are visible at rest (treated with fillers); Dynamic lines appear only with muscle movement (treated with Botox).
• Contrast Dermabrasion vs. Microdermabrasion: Dermabrasion penetrates to the dermis for scar resurfacing; Microdermabrasion only suctions dead superficial skin.
• Contrast Mastopexy vs. Breast Reduction: Mastopexy preserves breast volume while lifting; Breast Reduction removes glandular tissue and skin to reduce size.
• Contrast Subglandular vs. Submuscular Implants: Subglandular is easier but requires thick skin (>2cm pinch); Submuscular prevents "double bubble" deformity in patients with thin skin.
• Contrast Inframammary vs. Periareolar Approach: Inframammary has less risk of contamination; Periareolar carries a higher risk of abscess due to bacteria in milk ducts.
• Contrast Standard vs. Fleur-de-lis Abdominoplasty: Standard abdominoplasty uses a transverse incision for horizontal laxity; Fleur-de-lis adds a vertical incision for massive vertical skin excess.
• Contrast Ablative vs. Non-Ablative Lasers: Ablative (CO2) has superior results but 2-week downtime; Non-ablative (Nd:YAG) has less downtime (3-4 days) but subtle results.
• Contrast Liposuction vs. Weight Loss Surgery: Liposuction removes localized fat for contour in healthy-weight patients; Bariatric surgery is for systemic weight reduction in obese patients.
• Contrast Reconstructive vs. Aesthetic Surgery: Reconstructive surgery treats pathologic deformities (congenital/acquired); Aesthetic surgery improves appearance of normal structures.
• Contrast Hyaluronic Acid vs. Poly-L Lactic Acid: Hyaluronic Acid is a reversible, volume-adding gel; Poly-L Lactic Acid (Sculptra) is a bio-stimulatory filler for longer-term tissue development.
• Distinguish Fitzpatrick Skin Type: Patients with Skin Type 3 and above (common in Filipinos) must avoid sun for 2 weeks post-laser to prevent melasma and hyperpigmentation.
• Distinguish Facelift Vectors: SMAS tightening should follow an oblique/upward vector (toward cheekbones), not a horizontal/backward vector.
• Distinguish Areola Size: An aesthetically pleasing areola is 4–6 cm in diameter; larger areolas are corrected via specialized incisions during mastopexy.
• Distinguish Hematoma Management: Use COLD compress for the first 48 hours (vasoconstriction); use WARM compress after 72 hours (vasodilation to absorb fluid).

QA

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I. General Principles of Aesthetic Surgery

1. What is the primary goal of Aesthetic Surgery? | Reshape normal structures
2. What is the most important outcome parameter for Aesthetic Surgery? | Patient satisfaction
3. What are the guiding principles (3) of Aesthetic Surgery? | 1) Human proportions
   2) Vitruvian man
   3) Golden ratio
4. When must clinical photography be documented for Aesthetic Surgery? (4) | 1) Pre-op
   2) Intraoperatively
   3) Immediately post-op
   4) Remodeling phase
5. What are the segments of the face in Aesthetic Surgery facial analysis? (3) | Upper, middle, and lower thirds
6. What landmark is used for vertical facial proportions in Aesthetic Surgery? | Medial epicanthus

II. Minimally Invasive and Non-Invasive Procedures

7. What type of lines are the primary target for Soft Tissue Fillers? | Static lines
8. What type of lines are the primary target for Neuromodulators (Botox)? | Dynamic lines
9. What is the mechanism of action for Soft Tissue Fillers? | Fills contour differences
10. What is the mechanism of action for Neuromodulators (Botox)? | Blocks Acetylcholine release
11. What are common treatment areas for Soft Tissue Fillers? (4) | Nasolabial folds, lips, cheeks, and temples
12. What are the common treatment areas for Botox? (3) | Glabellar lines, crow's feet, and forehead lines
13. What are the common materials used in Soft Tissue Fillers? (2) | Hyaluronic Acid and Calcium hydroxylapatite
14. What material is used in Neuromodulators? | Botulinum Toxin A
15. What is the typical duration of Soft Tissue Fillers? | 6 - 15 months
16. What is the typical duration of Neuromodulators (Botox)? | 4 - 6 months
17. What characteristic determines the viscosity of Hyaluronic Acid Fillers? | G prime
18. What filler material stimulates natural collagen and is used for a "chiseled" jawline? | Calcium Hydroxylapatite (Radiesse)
19. What filler is specifically FDA-approved for HIV-associated lipodystrophy? | Poly-L Lactic Acid (Sculptra)
20. What is the gold standard laser for facial wrinkles that carries a hyperpigmentation risk in Asians? | Ablative Lasers (CO2)
21. What are the three levels of Chemical Peels? | 1) Superficial
    2) Moderate
    3) Deep
22. What procedure involves mechanical removal of skin layers to resurface acne scars? | Dermabrasion
23. Which device removes dead skin via suction without reaching the dermis? | Microdermabrasion
24. Which non-invasive treatments use radiofrequency or ultrasound to tighten skin? (2) | Ultherapy and Thermage
25. Which procedure uses focused cooling to target subcutaneous fat? | Coolsculpting (Cryotherapy)

III. Facial Danger Zones and Anatomy

26. Where is Facial Danger Zone 1 located? | 6.5 cm below auditory canal
27. Where is Facial Danger Zone 2 located? | Above zygoma to lateral eyebrow
28. Where is Facial Danger Zone 3 located? | Midmandible, posterior to commissure
29. Where is Facial Danger Zone 4 located? | Triangle: malar to mandible angle
30. Where is Facial Danger Zone 5 located? | Superior orbital rim
31. Where is Facial Danger Zone 6 located? | 1 cm below inferior orbital rim
32. Where is Facial Danger Zone 7 located? | Midmandible below 2nd premolar
33. Which nerve is involved in Facial Danger Zone 1? | Great auricular nerve
34. Which nerve is involved in Facial Danger Zone 2? | Temporal branch of Facial nerve
35. Which nerve is involved in Facial Danger Zone 3? | Marginal mandibular nerve
36. Which nerve branches are involved in Facial Danger Zone 4? (2) | Zygomatic and Buccal branches
37. Which nerves are involved in Facial Danger Zone 5? (2) | Supraorbital and Supratrochlear nerves
38. Which nerve is involved in Facial Danger Zone 6? | Infraorbital nerve
39. Which nerve is involved in Facial Danger Zone 7? | Mental nerve
40. What is the sign of injury in Facial Danger Zone 1? | Numbness of ear/cheek
41. What is the sign of injury in Facial Danger Zone 2? | Forehead paralysis
42. What is the sign of injury in Facial Danger Zone 3? | Paralysis of lower lip
43. What is the sign of injury in Facial Danger Zone 4? | Paralysis of upper lip/cheek
44. What is the sign of injury in Facial Danger Zone 5? | Numbness of forehead/scalp
45. What is the sign of injury in Facial Danger Zone 6? | Numbness of upper lip/nose
46. What is the sign of injury in Facial Danger Zone 7? | Numbness of lower lip/chin
47. What is the muscle-fascial layer of the face that originates as the platysma? | SMAS
48. Injury to the Temporal branch of the Facial Nerve in Zone 2 causes paralysis of which muscle? | Frontalis muscle
49. Which Facial Danger Zones are associated with sensory deficits? (4) | Zones 1, 5, 6, and 7

IV. Facial Surgical Procedures

50. What is the term for the descent of eyebrows due to aging? | Brow Ptosis
51. What is the current gold standard for rejuvenation of the brow? | Endoscopic Brow Lift
52. What condition involves excess upper eyelid skin that may disrupt vision? | Dermatochalasis
53. What is the schedule for compresses post-Blepharoplasty? | Cold (48h), then Warm (Day 3)
54. Successful Rhytidectomy must address which anatomical layer? | SMAS layer
55. Asian Rhinoplasty typically focuses on the augmentation of which two structures? | Nasal dorsum and tip
56. What cartilage graft provides tripod support in Rhinoplasty? | Columellar Strut

V. Aesthetic Breast Surgery

57. What is the primary goal of Mastopexy? | Breast Lift
58. What is the primary goal of Augmentation Mammaplasty? | Increase breast size
59. What is the primary goal of Breast Reduction? | Decrease volume and skin
60. What is the screening requirement for patients ≥ 40 years old before Breast Surgery? | Mammogram
61. What is the symptomatic triad for Breast Reduction? (3) | Back pain, Bra grooving, Rashes
62. What congenital condition involving underdeveloped pectoralis muscles requires Breast Augmentation? | Poland Syndrome
63. What skin pinch test result indicates the need for a Submuscular Implant? | Less than 2 cm
64. Which approach for breast implants is considered the safest with direct visualization? | Inframammary Approach
65. What are the three stages of Physiologic Gynecomastia? | Neonatal, Puberty, and Senescence
66. List drugs that may induce Pathologic Gynecomastia (6). | Digitalis, Marijuana, Alcohol, Anabolic steroids, Spironolactone, Cimetidine
67. Which system is used to assess the severity of Gynecomastia? | Simons Grading Classification

VI. Body Contouring and Liposuction

68. What is the true purpose of Liposuction? | Body contouring
69. What substances are used in the Tumescent Technique? (2) | Lidocaine and Epinephrine
70. What is the term for a redundancy of skin and fat hanging over the pubic area? | Abdominal Wall Pannus
71. What are the key maneuvers in Abdominoplasty? (3) | 1) Skin removal
    2) Fascial tightening
    3) Umbilicus transposition
72. Which procedure treats both horizontal and vertical skin excess in massive weight loss? | Fleur-de-lis Abdominoplasty
73. What procedure involves fat transfer from a donor site to the buttocks? | Autologous Fat Grafting

VII. High-Yield Distinctions for Exams

74. Contrast Static vs. Dynamic Lines by treatment. | Static (Fillers); Dynamic (Botox)
75. Contrast Dermabrasion vs. Microdermabrasion by skin depth. | Dermabrasion reaches the dermis
76. Contrast Mastopexy vs. Breast Reduction by volume. | Mastopexy preserves volume
77. Contrast Subglandular vs. Submuscular Implants for thin skin. | Submuscular is preferred
78. Contrast Inframammary vs. Periareolar Approach by abscess risk. | Periareolar has higher risk
79. Contrast Standard vs. Fleur-de-lis Abdominoplasty by incision. | Fleur-de-lis adds vertical incision
80. Contrast Ablative vs. Non-Ablative Lasers by downtime. | Ablative (2 weeks); Non-Ablative (3-4 days)
81. Contrast Liposuction vs. Weight Loss Surgery by goal. | Liposuction (Contour); Bariatric (Reduction)
82. Contrast Reconstructive vs. Aesthetic Surgery by structures. | Reconstructive (Pathologic); Aesthetic (Normal)
83. Contrast Hyaluronic Acid vs. Poly-L Lactic Acid by effect. | HA (Reversible); Poly-L (Bio-stimulatory)
84. What must Fitzpatrick Type 3+ patients avoid post-laser? | Sun for 2 weeks
85. What is the correct vector for SMAS tightening in a Facelift? | Oblique/upward vector
86. What is the aesthetically pleasing diameter for an Areola? | 4–6 cm
87. Contrast the timing of cold vs warm compress for Hematoma Management. | Cold (48h); Warm (72h)

3 - Basic Neuroradiology and Neurosurgery

Summary

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I. Fundamentals of Neuroradiology

• The Attenuation Coefficient represents a constant value of how much X-ray radiation is absorbed by a specific tissue.
• Hounsfield Units (HU) are a quantitative scale used in CT scans to describe radiodensity relative to water (0 HU).
• On a CT Scan, lower HU values (e.g., -1000 for Air) appear darker/black, while higher HU values (e.g., +1000 for Bone) appear whiter/hyperdense.
• On a CT Scan, Acute Blood (Hemorrhage) is hyperdense (75-80 HU) while CSF is hypodense (approx. +5 HU).
• CT Scan is the first study of choice for suspected acute intracranial disease due to high sensitivity for fractures and acute hemorrhage.
• The Axial Cut of a CT scan provides a "top view" of the brain.
• The Sagittal Cut of a CT scan provides a "side view" of the brain.
• The Coronal Cut of a CT scan provides a "front view" of the brain.
• Contrast-Enhanced CT is specifically indicated for visualizing neoplastic (tumors) or infectious (abscess) processes.

II. Surgical Management of Traumatic Brain Injury (TBI)

• An Acute Epidural Hematoma (EDH) requires surgical evacuation if the volume is > 30 cm³, regardless of the patient's GCS.
• An Acute Epidural Hematoma (EDH) in a patient with GCS < 9 and pupillary anisocoria is an indication for surgery.
• The Management of EDH can be observation if the volume is < 30 cm³, thickness is < 15 mm, and midline shift is < 5 mm in a conscious patient.
• An Acute Epidural Hematoma (EDH) classically appears as a biconvex/lentiform hyperdense shape that does not cross suture lines.
• The most common source of bleeding in an Acute Epidural Hematoma (EDH) is the middle meningeal artery.
• Traumatic Parenchymal Lesions require surgery if there is progressive neurologic deterioration, refractory ICP, or a clot volume > 50 cm³.
• A Frontal or Temporal Contusion requires surgery if the volume is > 20 cm³ AND there is a midline shift > 5 mm or SIS compression.
• Delayed Traumatic Intracerebral Hemorrhage most likely occurs within the first 24 hours post-trauma; repeat imaging at 24 hours is often necessary.
• A Posterior Fossa Mass Lesion requires surgical intervention if it causes brainstem compression or obstructive hydrocephalus (obliterated 4th ventricle).
• A Depressed Skull Fracture requires surgery if the depression exceeds the thickness of the adjacent skull or if it is an open fracture with dural penetration.

III. CNS Tumors and Histopathology

• Glioblastoma (GBM) median survival is approximately 15 months, even with optimal treatment.
• Hemangioblastoma is associated with Von Hippel-Lindau syndrome when multiple lesions are present.
• Pilocytic Astrocytoma may be seen as part of Neurofibromatosis Type 1.
• The hallmark of Neurofibromatosis Type 2 is the presence of bilateral vestibular schwannomas.
• MGMT-methylation is a biomarker in GBM that indicates an improved response to temozolomide chemotherapy.

IV. Traumatic Spinal Cord Injury (TSI) Management

• The Airway Management in TSI must assume cervical spine injury; use the Jaw Thrust with caution and maintain rigid collar immobilization.
• The primary goal in Circulation for TSI is to keep SBP > 90 mmHg and maintain MAP 85-90 mmHg for the first 7 days.
• Neurogenic Shock in TSI is characterized by the triad of hypotension, bradycardia, and warm, dry skin due to loss of sympathetic tone.
• The first line of treatment for Hypotension in TSI is fluid resuscitation, followed by Norepinephrine as the preferred vasopressor.
• The Canadian C-Spine Rule mandates imaging for patients age ≥ 65 or those with a "dangerous mechanism" of injury.
• The NEXUS Criteria allow for clinical clearance of the C-spine only if there is no midline tenderness, no focal neuro deficit, and no distracting injuries.
• Clinical Clearance of the C-spine involves removing the collar and having the patient rotate their head 45 degrees to each side without pain.
• Complete Cervical TSI (C1-C4) requires early elective intubation due to the high risk of respiratory arrest and loss of diaphragmatic innervation.
• Quad Breathing is a sign of cervical TSI where the abdomen moves out sharply during inspiration, indicating the need for elective intubation.
• High Cervical Spine Injuries (above C3) are associated with the loss of diaphragmatic function (phrenic nerve C3, C4, C5).
• The use of Corticosteroids for acute traumatic spinal cord injury is no longer considered the standard of care.

V. Advanced Imaging in Neurosurgery

• T1-Weighted MRI + Gadolinium is the gold standard for identifying blood-brain barrier breakdown in tumors and abscesses.
• FLAIR (Fluid-Attenuated Inversion Recovery) is a T2 MRI sequence that suppresses CSF signal to better visualize periventricular pathology like MS plaques.
• Diffusion-Weighted Imaging (DWI) is the gold standard for diagnosing acute ischemic stroke within minutes of onset.
• STIR (Short Tau Inversion Recovery) sequences are used in spine imaging to identify bone marrow edema, distinguishing acute from chronic fractures.
• Gradient Echo (GRE) MRI is essential for detecting micro-hemorrhages and diagnosing Diffuse Axonal Injury (DAI).
• Absolute Contraindications to MRI include cardiac pacemakers, ICDs, and retained metallic foreign bodies in the orbits.

VI. ASIA Impairment Scale (AIS) for Spinal Cord Injury

• The ASIA Grade A classification signifies a Complete injury with no sensory or motor function in sacral segments S4-S5.
• The ASIA Grade B classification signifies Sensory Incomplete (sensory preserved below level, but no motor function).
• The ASIA Grade C classification signifies Motor Incomplete where at least half of the key muscles below the injury level have a grade LESS than 3.
• The ASIA Grade D classification signifies Motor Incomplete where at least half of the key muscles below the injury level have a grade GREATER than or equal to 3.
• The ASIA Grade E classification signifies Normal motor and sensory function in a patient who previously had deficits.

VII. High-Yield Distinctions for Exams

• Contrast Neurogenic Shock vs. Spinal Shock: Neurogenic shock is a hemodynamic state (hypotension/bradycardia); Spinal shock is a neurologic state (loss of reflexes).
• Contrast CT vs. MRI for Blood: CT is superior for acute hemorrhage (white/hyperdense); MRI sequences like GRE are superior for chronic or micro-hemorrhages.
• Contrast Epidural (EDH) vs. Subdural (SDH) Hematoma: EDH is biconvex and respects suture lines; SDH is crescent-shaped and crosses suture lines.
• Contrast C1 vs. C2 Fractures: Use the Rule of Spence (lat mass displacement >7mm) to identify transverse ligament rupture in Jefferson (C1) fractures.
• Contrast T1 vs. T2 MRI: T1 is best for anatomical detail (CSF is dark); T2 is best for edema/water detection (CSF is bright).
• Contrast Canadian C-Spine vs. NEXUS: Canadian C-Spine involves high-risk factors (age/mechanism); NEXUS focuses on the absence of "5 criteria" (tenderness, intoxication, neuro deficit, etc.).
• Contrast Pilocytic Astrocytoma vs. Medulloblastoma: Both are in the posterior fossa of children, but Pilocytic is benign/cystic while Medulloblastoma is malignant/solid.
• Contrast Vasopressors in TSI: Fluid resuscitation is 1st line; Norepinephrine is preferred over others to maintain MAP.
• Contrast Dermabrasion vs. Microdermabrasion: Dermabrasion reaches the dermis for acne scars; microdermabrasion only removes dead skin via suction.
• Contrast Standard vs. Fleur-de-lis Abdominoplasty: Fleur-de-lis adds a vertical incision to address massive weight loss skin excess.

QA

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I. Fundamentals of Neuroradiology

1. Compare the Primary Parameter of CT Scan vs. MRI. | Density vs. Intensity
2. Compare the Core Principle of CT Scan vs. MRI. | Attenuation vs. Magnetic signals
3. Compare the Appearance of Bone on CT Scan vs. MRI. | Hyperdense vs. Signal Void
4. Compare the Best Utility of CT Scan vs. MRI. | Hemorrhage/fractures vs. Soft tissue/tumors
5. Compare the Surgical Value of CT Scan vs. MRI. | Quick acquisition vs. Detailed anatomy
6. What is the definition of the Attenuation Coefficient? | X-ray radiation absorption constant
7. What are Hounsfield Units (HU)? | Radiodensity scale relative to water
8. Contrast CT Scan HU values for Air vs. Bone. | Air: -1000; Bone: +1000
9. Contrast CT Scan HU values for Acute Blood vs. CSF. | Blood: 75-80; CSF: +5
10. What is the first study of choice for suspected acute intracranial disease? | CT Scan
11. What view does an Axial Cut of a CT scan provide? | Top view
12. What view does a Sagittal Cut of a CT scan provide? | Side view
13. What view does a Coronal Cut of a CT scan provide? | Front view
14. What are the indications (2) for Contrast-Enhanced CT? | Neoplastic or infectious processes

II. Surgical Management of Traumatic Brain Injury (TBI)

15. What is the volume requirement for surgery in Acute Epidural Hematoma (EDH)? | Greater than 30 cm³
16. What GCS and pupil findings indicate surgery for Acute Epidural Hematoma (EDH)? | GCS < 9; pupillary anisocoria
17. What are the observation criteria (3) for Management of EDH? | 1) Volume < 30 cm³
    2) Thickness < 15 mm
    3) Shift < 5 mm
18. What is the classic appearance of an Acute Epidural Hematoma (EDH)? | Biconvex/lentiform hyperdense shape
19. What is the most common bleeding source in Acute Epidural Hematoma (EDH)? | Middle meningeal artery
20. What are the surgical criteria (3) for Traumatic Parenchymal Lesions? | 1) Deterioration
    2) Refractory ICP
    3) Clot > 50 cm³
21. What are the surgical criteria (2) for Frontal or Temporal Contusion? | 1) Volume > 20 cm³
    2) Midline shift > 5 mm
22. When does Delayed Traumatic Intracerebral Hemorrhage most likely occur? | Within first 24 hours
23. What are the surgical indications (2) for a Posterior Fossa Mass Lesion? | Brainstem compression; obstructive hydrocephalus
24. When does a Depressed Skull Fracture require surgery? | Depression > skull thickness; open fracture

III. CNS Tumors and Histopathology

25. What are the markers/location for Pilocytic Astrocytoma? | Rosenthal fibers; Posterior fossa
26. What is the classic histopathology of Ependymoma? | Rosettes; perivascular pseudorosettes
27. What are the markers/appearance for Oligodendroglioma? | Fried egg; 1p/19q codeletion
28. What is the histopathology and protocol for Glioblastoma (GBM)? | Necrosis; microvascular proliferation; Stupp Protocol
29. What is the marker and risk of Medulloblastoma? | Homer Wright rosettes; CSF seeding
30. What is the cell origin of Meningioma? | Arachnoid cap cells
31. What nerve and syndrome are associated with Vestibular Schwannoma? | CN VIII; Neurofibromatosis Type 2
32. What is the median survival for Glioblastoma (GBM)? | Approximately 15 months
33. What syndrome is associated with Hemangioblastoma? | Von Hippel-Lindau syndrome
34. Which tumor is seen in Neurofibromatosis Type 1? | Pilocytic Astrocytoma
35. What is the hallmark of Neurofibromatosis Type 2? | Bilateral vestibular schwannomas
36. What is the clinical significance of MGMT-methylation in GBM? | Improved response to temozolomide

IV. Traumatic Spinal Cord Injury (TSI) Management

37. What is the priority for Airway Management in TSI? | Jaw Thrust; collar immobilization
38. What are the 7-day hemodynamic goals for TSI Circulation? | SBP > 90; MAP 85-90
39. What is the clinical triad of Neurogenic Shock? | Hypotension; bradycardia; warm skin
40. What is the first line and preferred pressor for Hypotension in TSI? | Fluid resuscitation; Norepinephrine
41. What triggers imaging under the Canadian C-Spine Rule? | Age ≥ 65; dangerous mechanism
42. What are the NEXUS Criteria for clinical clearance? | No tenderness, neuro deficit, or distraction
43. How is Clinical Clearance of the C-spine performed? | 45-degree head rotation without pain
44. Why does Complete Cervical TSI (C1-C4) require early intubation? | Loss of diaphragmatic innervation
45. What does the sign Quad Breathing indicate? | Need for elective intubation
46. Which nerve is lost in High Cervical Spine Injuries (above C3)? | Phrenic nerve
47. Is the use of Corticosteroids recommended in acute TSI? | No; not standard of care

V. Advanced Imaging in Neurosurgery

48. What is the gold standard for identifying blood-brain barrier breakdown? | T1-Weighted MRI + Gadolinium
49. What is the primary utility of FLAIR MRI? | Suppresses CSF; visualizes periventricular pathology
50. What is the gold standard for acute ischemic stroke? | Diffusion-Weighted Imaging (DWI)
51. What is the utility of STIR sequences in spine imaging? | Identify bone marrow edema
52. What is Gradient Echo (GRE) MRI used to detect? | Micro-hemorrhages; Diffuse Axonal Injury
53. What are the absolute Contraindications to MRI? | Pacemakers, ICDs, metallic orbital bodies

VI. ASIA Impairment Scale (AIS) for Spinal Cord Injury

54. Define ASIA Grade A. | Complete; no S4-S5 function
55. Define ASIA Grade B. | Sensory Incomplete; no motor function
56. Define ASIA Grade C. | Motor Incomplete; < half muscles ≥ 3
57. Define ASIA Grade D. | Motor Incomplete; ≥ half muscles ≥ 3
58. Define ASIA Grade E. | Normal motor and sensory function

VII. High-Yield Distinctions for Exams

59. Contrast Neurogenic Shock vs. Spinal Shock. | Hemodynamic state vs. Neurologic state
60. Contrast CT vs. MRI for Blood. | Acute hemorrhage vs. Chronic/Micro-hemorrhage
61. Contrast Epidural (EDH) vs. Subdural (SDH) shape. | Biconvex vs. Crescent-shaped
62. How is the Rule of Spence used in C1 vs. C2 fractures? | Identifies transverse ligament rupture
63. Contrast T1 vs. T2 MRI for CSF appearance. | T1 CSF dark; T2 CSF bright
64. Contrast Canadian C-Spine vs. NEXUS. | High-risk factors vs. Absence of 5 criteria
65. Contrast Pilocytic Astrocytoma vs. Medulloblastoma. | Benign/Cystic vs. Malignant/Solid
66. Comparison of Vasopressors in TSI. | Norepinephrine preferred to maintain MAP
67. Contrast Dermabrasion vs. Microdermabrasion. | Dermis depth vs. dead skin suction
68. Contrast Standard vs. Fleur-de-lis Abdominoplasty. | Standard vs. 추가 (vertical) incision