Skin Surgery JC081: Skin Ulcers: Skin And Subcutaneous Lesions, Skin Cancer Flashcards

1
Q

Skin and SC lesions

A
  • Common
  • Patients’ worries
    —> unknown nature
    —> malignancy
    —> appearance

Diagnosis:
- Sometimes obvious
- History + P/E follow
- Regional exam + Systemic review as indicated
- Lesion may represent an ***occult systemic problem

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2
Q

History taking of Skin + SC lesions

A
  1. Onset
  2. Progression
  3. Pain
  4. Discharge / Bleeding / Ulcer
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3
Q

P/E of Skin + SC lesions

A
  1. Site, Size, Shape, Colour
  2. Consistency, Surface, Border
  3. **Tenderness, **Temperature (infection, inflammatory)
  4. ***Pulsatility, Emptying (vascular lesion)
  5. ***Skin / Deep fixation
  6. ***Transillumination (cystic lesions)
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4
Q

Management of Skin + SC lesions

A
  1. Observation / Reassurance
  2. Excision / Destruction (e.g. shave, liquid N2)
  3. ***Excisional biopsy (suspicious lesions)
  4. ***Incisional biopsy +/- Definitive treatment (unknown nature)
  5. ***Wide excision +/- Reconstruction (malignant lesions)
  6. Radiotherapy
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5
Q

Skin structure

A
  1. Epidermis
    - 3-5 cells thick
    - Impermeable stratum corneum
  2. Dermis
    - 0.8-2.5mm thick (depends on location)
    - fibrous + tough
  3. Hypodermis
    - indistinct loose fibrofatty layer
    - contains ***adnexal structures (vessels, hair follicles, sebaceous glands, sweat glands)
  4. SC fat
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6
Q

***DDx of Skin + SC lesions

A
  1. Epidermis
    Benign:
    - Skin tags
    - **Warts
    - **
    Seborrhoeic keratosis
    - ***Keratoacanthoma

Premalignant:
- Solar keratosis
- Bowen’s disease
- Erythroplasia of Queyrat

Malignant:
- **SCC
- **
Basal cell carcinoma

  1. Epidermal-Dermal region (Melanocytic lesion)
    - Benign pigmented naevi
    - **
    Malignant melanoma (
    *lethal)
  2. Dermis
    - Pyogenic granuloma
    - Histiocytoma
    - Keloid
    - Secondary carcinomas
    - Kaposi’s sarcoma
  3. Skin appendages
    - **Epidermoid (sebaceous) cyst
    - **
    Dermoid cyst
    - Pilonidal sinus
    - Benign appendage tumour
  4. Hypodermis / Deeper tissues
    - Lipoma
    - Liposarcoma
    - **Neurofibroma + Sarcoma
    - **
    Neurofibromatosis
    - Schwannoma
    - Deeper lesions e.g. ganglion
  5. Vascular origin
    - Campbell de Morgan spots (aka Cherry angioma, Senile haemangioma)
    - Spider naevi
    - Angioma
    - Glomus tumour of digits
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7
Q

Verruca vulgaris (Common warts) (+ SpC Revision)

A
  • Multiple papular skin-coloured lesions
  • Irregular thickened keratinised (warty) top
  • Caused by ***HPV
  • Related to trauma, on hand / foot
  • Contagious + often multiple
  • Poor immunity —> Multiple viral warts
  • Brown / gray with a rough surface (***Warty spikes)
  • Plantar warts: **Flattened + **Painful
  • Genital warts: Soft + **Fleshy (*Condylomata acuminata)
  • Can recur after treatment

Treatment:
1. Heat cautery
2. Cryosurgery / Cryotherapy
3. Laser (CO2)
4. Surgery (for persistent / recurrent cases)

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8
Q

Corn + Callouses

A
  • Massive thickening of ***stratum corneum
  • Due to chronic trauma / irritation
  • Corn: ***smaller, well marginated, square-shouldered
  • Callouses: ***larger, more diffused, slope-shouldered
  • Management: removal of irritation, paring, keratolytic agent (10-20% ***salicylic acid)
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9
Q

Common cystic lesions (+ SpC Revision)

A
  1. Epidermoid cyst (Sebaceous cyst)
    - true cyst (epithelial lining)
    - ?hair follicle origin
    - spherical, **attached to skin (always **mobile), overlying **punctum
    - contains cheesy **
    keratin material **NOT sebum
    - may get **
    infected (red, swollen, tender)
    - multiple: consider ***Gardner’s syndrome (associated with osteoma, fibromas, intestinal fibromatoses, lipomas, leiomyomas, polyposis coli)
    - complications: infection, sebaceous horn (sebaceous content keep forming without being removed then dried up)
    - management: Excision
  2. Implantation dermoid
    - epidermal fragment (by penetrating injury) driven into dermis
    - lined by **epidermis producing keratin material
    - contains white amorphous material
    - tensely cystic (continuous proliferation of epithelium)
    - history of **
    trauma + presence of scar
    - common sites on fingers
    - management: Excision (to avoid infection)
  3. Other epidermoid cysts:
    Milia
    - small 1-2mm epidermoid cysts on ***face

Pilar cyst
- trichilemmal cyst / wen
- ***slow-growing firm cyst on the scalp

Steatocystoma multiplex
- true sebaceous cyst —> contains ***sebum

  1. **Dermoid cyst (sequestration dermoid)
    - **
    congenital cystic lesions growing slowly
    - occurs at ***embryonic fusion line regions (e.g. midline of scalp, external angle of eye, lower mandible)
    - contains keratin, hair, sebaceous glands etc.
    - management: excision
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10
Q

Keratotic lesions (+ SpC Revision)

A
  1. Seborrhoeic keratosis (Basal cell papilloma / Seborrhoeic wart / Senile wart)
    - common in **elderly
    - **
    brownish-black, raised, well-marginated
    - **plaque-like papules, “stuck-on”, square-shouldered
    - feels **
    waxy + irregular
    - proliferation of ***basal cells of epidermis
    - face, neck, chest wall
    - management: observe, cryotherapy, curettage, shaving, excision
  2. Actinic keratosis (Solar keratosis, Senile keratosis)
    - **sun-damaged skin by UV, in exposed parts
    - dry, scaly, crusty top, erythematous based
    - early lesions: flat, roughened / scaly papules (which could just be palpable)
    - hyperkeratosis + acanthosis (i.e. thickening of skin) —> **
    pre-malignant
    - excision
    - if multiple: excision, curettage, cryosurgery, 5FU creams
  3. Keratoacanthoma (Molluscum sebaceum)
    - from squamous cell of hair follicles
    - same area as BCC
    - can be **indistinguishable from BCC
    - **
    dome / nodular-shaped, flesh-coloured
    - **central crater filled with **keratin plug (Look like tumour central ulceration)
    - natural history: **rapid growth for a few weeks —> static for a few months —> **involution spontaneously, leaving an ugly scar
    - ***?variant of SCC
    - management: excisional biopsy, ?observation, ?RT
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11
Q

Naevi

A

Developmental abnormalities: Hyperplasia of incompletely differentiated tissue elements

Types:
1. Melanocytic naevus (Mole)
2. Strawberry naevus (Infantile haemangioma)
3. Sebaceous naevus (Naevus of Jadassohn)

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12
Q
  1. Melanocytic naevus (Mole)
A
  • Very common, benign
  • Depends on location of naevus cells:
    1. Junctional (child, flat, darkly pigmented)
    2. Compound (younger adult, raised, variable pigmentation)
    3. Intradermal (older adult, dome-shaped, deep seated, lighter / flesh-coloured)
    4. Congenital (giant / hairy) (big, hairy, dark, raised, thick (**risk of malignant change))
    5. **
    Dysplastic
  • uncommon in Asians, usually multiple, occasionally solitary
  • irregular border + speckled pigmentations
  • 2 major groups:
    —> Sporadic: Caucasians, fair skin, poorly tanned, excessive sunlight exposure with freckles etc.
    —> Familal: Dysplastic naevus syndrome, run in families, uncommon, up to 400x lifetime risk of malignant change
    6. Others (blue, Spitz, halo etc)
  • risk of malignant changes very small except:
    —> Dysplastic naevus (esp. with family / personal history)
    —> Giant congenital melanocytic naevus (“bathing trunk”, life-long surveillance)
    —> >50, >2mm size
  • DDx: **Melanoma, **BCC, ***Seborrhoeic keratosis
  • when in doubt —> Excisional / Incisional biopsy
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13
Q

Dermatofibroma (Histiocytoma, Sclerosing angioma)

A
  • Firm skin nodule, 0.5-3 cm
  • Fibrosis + Vascularity + Fe pigmentation
  • Benign
  • ***History of trauma / insect bite
  • Deep reddish-brown
  • ?Histiocytic origin
  • DDx: ***Dermatofibrosarcoma protuberans (malignant)

Dermatofibrosarcoma protuberans (DFSP)
- **locally aggressive
- painless, indurated plaque with irregular nodules
- skin-coloured, border not well defined
- ?fibroblastic origin, ?malignant variant of DF
- infiltrative histologically with cords / nests of cells invading into adjacent soft tissue
- prone to **
local recurrence, **seldom metastasise
- management: **
wide excisional margin +/- RT

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14
Q

Neurofibroma

A

From supporting ***fibroblasts of peripheral nerves
(- Neurilemmoma = Schwannoma (from neurilemmal cells, encapsulated, lobulated firm tumour))

  1. Solitary:
    - SC, **tender, **firm nodule, ***mobile laterally
  2. Multiple:
    - sessile / pedunculated, skin-coloured / brownish, well-circumscribed
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15
Q

Neurofibromatosis

A
  • AD inheritance
  • NF-1, NF-2 (depending on clinical features, genes)
  • Multiple lesions of different sizes, ***cafe au lait pigmentations
  • ***Acoustic neuroma (type 2)
  • deformities / disfigurement
  • **possible malignant change
    (- **
    Plexiform NF: skin thickened with foldings, myxfibromatous degeneration, sporadic / familial)
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16
Q

Lipoma (+ SpC Revision)

A
  • commonest SC benign condition
  • **SC lump / mass (1-20cm) —> **Can pinch skin over lipoma
  • **Soft, **smooth surface with ***lobulations + encapsulated
  • Diffuse / Well-defined lobulated mass
  • Diffuse: ***Madelung’s disease (extensive + big lipoma in nape of neck, upper back in chronic drinkers)
  • ***matured fat cells in thin fibrous capsule, grouped into lobules by vascular connective tissue septal
  • big lipoma: may be ***soft + fluctuant
  • management: conservative, excision, liposuction
  • potential malignant change: ***Painful, Rapidly enlarging, Skin changes, Firm consistency may indicate malignancy (sarcomatous changes)
17
Q

Vascular anomaly

A
  1. Vascular tumours
    - Rapid proliferating vascular endothelium
    - usually **not present at birth
    - rapidly ↑ in size
    - may involute
    - F:M = 3:1
    - 60% head and neck
    - **
    most common tumour of infancy
    - “strawberry naevus” (NOT a naevus but vascular tumour)

Types:
- Benign
- Locally aggressive / Borderline
- Malignant

  1. Vascular malformations
    - Congenital abnormal vascular anatomy + morphology
    - **present at birth (but may not be clinically apparent)
    - **
    grow in proportion to body size
    - can degenerate but also can hypertrophy (AVM)
    - ***Fast flow (e.g. Arterial) vs Slow flow
    - diagnosis by history + P/E
    - adjuncts: USG, MRI, Angiography

Types:
- Simple (Capillary / Lymphatic / Venous / ***Arteriovenous / Arteriovenous fistula)
- Combined

18
Q

Infantile hemangioma (Strawberry naevus)

A
  • NOT Congenital haemangioma!
  • Bright red haemangioma, in baby
  • appears shortly after birth —> rapidly grows for a few weeks to months —> static for some time —> involution
  • residual redundant skin / scar common

Management:
1. Observation
2. **Steroid, **β-blocker
3. Laser, Excision

19
Q

S/S of Vascular tumours

A

Intrinsic:
- **Bleeding
- **
Ulceration
- ***Kasabach-Merritt syndrome (Thrombocytopenia associated with kaposiform, haemangioendothelioma NOT common Haemangioma)

Extrinsic:
- Upper eyelids
—> deprivation **amblyopia (弱視) + failure to develop binocular vision
—> corneal distortion + astigmatism
- **
Airway obstruction (if grow in airway)

20
Q

Vascular malformations

A
  1. Arterial: Fast flow e.g. AVM
    - **Schobinger staging of AVM
    Stage 1: A blue-skin blush
    Stage 2: A mass associated with a bruit + a thrill
    Stage 3: A mass associated with ulceration, bleeding, pain
    Stage 4: Stage 3 lesions decompensation producing heart failure
    - Management: Pre-op **
    embolisation +/- Complete excision
  2. Venous
    - Slow flow
    - Management: Debulking, ***Sclerotherapy
  3. Capillary
    - e.g. ***Port-wine stain (on face)
    - Management: Laser
  4. Lymphatic
    - Macrocytic vs Microcytic
    - e.g. primary **lymphedema, **cystic hygroma
  5. Combination
    - e.g. Klippel Trenaunay Syndrome, Parkes Weber syndrome
21
Q

Port-wine stain

A
  • Capillary malformation
  • Present at birth, often on ***face / scalp
  • Flat / slightly elevated, ***reddish-blue to purplish
  • Advancing age —> thicker + nodular + hypertrophy
  • Associated with intracranial haemangioma —> DDx: ***Sturge-Weber syndrome
22
Q

Cystic hygroma

A
  • Collection of ***lymphatic sacs containing lymph
  • Failure of fusion of lymphatic channels
  • Present at birth (some later)
  • Usually root of neck, axilla, groin
  • **Soft, fluctuant, markedly **transilluminating
  • Management: Excision
23
Q

Skin tags (Papilloma)

A
  • More in advanced age
  • Benign
  • Proliferation of epidermis
  • Often multiple, 1-5 mm
  • Loose CT core with normal covering ***squamous epithelium (pigmented / keratinised)
  • Management: Excision, Laser
24
Q

Cutaneous horns

A

Descriptive term for any protuberant horny skin growth
- usually conical projection of ***keratinised material

Pathologically may be pre-malignant / benign / malignant:
1. **Actinic keratosis (with / without underlying SCC) (pre-malignant)
2. **
Seborrhoeic keratosis (benign)
3. ***SCC (malignant)

Management:
- Biopsy to confirm Dx + remove the horn

25
Pyogenic granuloma
- Benign condition - aka “Eruptive Haemangioma” - Induced by ***trauma - ***Red, fleshy, spherical nodule —> looks like a vascular tumour - ***Rapid + excessive growth of granulation tissue rich in ***blood vessels + inflammatory cells - ***Ulcerate + ***Bleed easily —> complaining of bleeding - Management: Excision, Curettage, Diathermy of base
26
Xanthelasma
- Deposition of ***lipid-laden macrophages in the superficial dermis - Soft, flat-topped yellow papules, may coalesce - Usually starts at upper eyelid near the medial canthus - About 1/3 of patients have hyperlipoproteinaemia - Management: Excision (may recur)
27
Benign tumours of Epidermal appendages
1. Hair follicle - Trichofolliculoma - Trichoepithelioma - Pilomatrixoma - Trichilemmoma 2. Sebaceous gland - Sebaceous adenoma - Adenoma 3. Sweat gland - Cylindroma - Synringoma Some have typical appearance, otherwise Dx confirmed on ***Histological exam
28
Pre-malignant skin conditions
1. ***Bowen’s disease, ***Paget’s disease of nipple 2. ***Xeroderma pigmentosa, Albinism 3. Chronic unstable scar / Destruction of skin - Chronic radiation dermatitis - Burn scar / Chronic osteomyelitis - ***Actinic keratosis
29
Bowen’s disease (***Squamous carcinoma-in-situ, Intraepidermal epithelioma) Paget’s disease of nipple
Bowen’s disease (***Squamous carcinoma-in-situ, Intraepidermal epithelioma) - Dysplastic cells confined to basal lamina (without definite invasion) - Thickened, reddish-brown, scaly patch with irregular border - If in penis: ***Erythroplasia of Queyrat with velvety-red plaque like appearance - Management: Excision, ***RT, ***Topical 5FU, Cryotherapy, Photodynamic therapy Paget’s disease of nipple: - Paget cells arise from ***mammary ducts to the nipple epidermis - ***Erythema + ***Eczematous lesion of nipple —> Erosion + Ulceration - 50-60 yo - 97% has underlying breast carcinoma, ~50% present with breast mass - Diagnosis: Incisional biopsy - Management: Treat underlying CA breast Extramammary Paget’s disease (EMPD) - ***Peno-scrotal area / Axilla area - Intraepithelial adenocarcinoma - Associated with underlying malignancy e.g. Prostate, Colon —> Need to screen - Management: Wide excision + Treat underlying malignancy if any
30
Common malignant skin cancers
Most common —> less common: 1. Basal cell carcinoma (BCC) 2. SCC 3. Malignant melanoma
31
1. Basal cell carcinoma (BCC) (+ SpC Revision)
- Due to ***excessive sunlight (UV) exposure - ***Commonest skin cancer - ***Low grade malignancy - ***Middle age / Elderly - Originate from ***basal epidermal cells (?pilosebaceous unit), slow growing - ***Face / scalp / ***neck / dorsum of hands / forearms - Also in patients: XP (xeroderma pigmentosum), ALB (albinism), Naevoid basal cell carcinoma syndrome, Sebaceous naevus (congenital lesion predisposing patients to BCC) - Multiple lesions are common - ***Locally invasive, ***slow growth, ***seldom metastasise - ***Serous discharge / bleeding, may be pigmented Clinical types: 1. ***Pigmented (common in orientals) 2. Nodular / Nodular-ulcerative 3. Superficial 4. Cystic 5. Morphreaform (sclerosing) Features: - Typical ulcer: ***Rolled edge + “cystic lesion” with ***pearly white edge + ***telangiectasia + central ulceration (Rodent ulcer) - Seldom spread to regional LN / by blood - Most lesions are well localised Management: 1. ***Excision with margins (***2-3 mm) (***3-5 mm (SpC Revision)), ***RT, 5FU cream 2. Cryotherapy, cauterisation, electro-desiccation should be used with ***much caution Beware of lesions: Post-op / RT recurrence - Medial canthus (眼角) - Peri-alar - Preauricular - Morpheaform type (∴ need a wider excision margin)-
32
2. Squamous cell carcinoma (SCC) (+ SpC Revision)
- Mostly a result of ***excessive sunlight (UV) exposure - Less common but ***more malignant than BCC + ***more rapid growth - Arise de novo / in pre-existing skin lesion - May develop from ***Actinic keratosis - Other causes: Carcinogens (RT, ***arsenic, chromium compounds, soot, tar), Chronic ***non-healing wounds, Unstable scars - Congenital diseases: XP, ALB - Immunosuppression: Diseases, Therapy Clinical features: - ***Everted edge / Exophytic growth - ***Irregular ulcer (e.g. ***Marjolin’s ulcer: malignant ulcer that develop over chronic wound, usually in sacrum / venous ulcer in ankle) - ***Indurated base + fixed to underlying structure - Evidence of sun-damage skin lesions - ***More aggressive: metastasis by ***lymphatic (examine LN) + ***haematogenous route Investigation: - Biopsy from ***edge of ulcer Management: - ***Wide excision (***10-15mm from Goddisk) +/- Reconstruction (∵ ***larger excision margin) - ***Block dissection for LN metastasis (e.g. axillary dissection) - RT
33
3. Malignant melanoma (+ SpC Revision)
- Malignant tumour of ***melanocytes (mesodermal) (normally located in basal layer of epidermis) - Cutaneous ones induced by ***sunlight (UV) - Arise de novo / from pigmented nevus - Less common than BCC, SCC - Other sites: ***mucous lining, ***choroid of eye, meninges, soft tissues (***amelanotic melanoma: no melanin production —> skin colour / erythematous colour Signs of malignancy in benign nevus: 1. Increase in size 2. Increase / Decrease in pigmentation 3. Ulcerate, weep, bleed 4. Itchy / burning sensation 5. Spread of pigmentation 6. LN enlargement - Any suspicion —> Biopsy (From CFB14: Mnemonic (ABCDE): - Asymmetry: Irregular shape - ***Border: Ragged outline - Colour: Variation - Diameter: >6mm across / recent increase in size - ***Elevation: Raised above surface of skin - Evolution: changes in size, colour, shape over time) Features: - ***Aggressive: metastasis to ***LN (Satellite / In-transit lesions; Regional / Distant LNs) / by ***blood - Most are ***darkly pigmented lesions - Recent onset / change in pigmentation of pre-existing lesion, irregular border / appearance - Increase in size, bleeding, loss of hair 5 Clinical types: 1. Superficial spreading 2. ***Nodular (most aggressive, invade deep in SC tissue early) 3. ***Lentigo maligna melanoma (least aggressive, face, nailbed) 4. Acral lentiginous melanoma (hand / foot) 5. Subungal melanoma (nail) Grading system: 1. ***Breslow scale (thickness) (more favoured for less observer’s variability) 2. ***Clark’s level of invasion (level 1-5) —> guide treatment + prognosis —> both correlate with LN metastasis + survival —> Thinner lesions —> Better prognosis Management: 1. Surgery - Only treatment method for potential cure - Excision margin: depends on ***Breslow’s thickness (i.e. depth of invasion), range from 1-3 cm 2. SLNB - For intermediate thickness tumour (e.g. 1-3 mm) —> carries ***prognostic information + facilitate ***staging 3. Regional LN dissection - Improves nodal control but ***NOT survival 4. Block dissection - For LN metastasis if no distant metastasis (- ?Role of elective block dissection in intermediate thickness tumour) 5. Others - Hyperthermia + Isolated limb perfusion for in-transit metastasis in specialised centre - Systemic chemotherapy ***not useful - Immunotherapy (control lesion + prolong survival): Anti-PD1 (Pembrolizumab, Nivolumab) (SpC PP)
34
Uncommon malignant tumours
1. Merkel cell carcinoma 2. Skin appendageal carcinoma 3. ***Sarcoma 4. Malignant nerve sheath tumour 5. Angiosarcoma 6. ***Lymphoma 7. ***Metastatic tumour If not sure —> biopsy
35
Benign skin tumours vs Malignant skin tumours
Benign skin tumours: - In young patients except Melanoma, Sarcoma Features: - Remain static in size / grow in proportion with patients - ***Do NOT ulcerate / bleed - ***Well defined regular border - Can be raised / flat - No enlarged regional LN Malignant skin tumours: - More common in elderly - ***Grow in size - ***Arise from pre-existing lesions e.g. naevus, scar - ***Ulcerate / Bleed - ***Irregular / poorly defined border - ***Raised - Enlarged regional LN - ***Satellite lesions (e.g. malignant melanoma)
36
Ambulatory Surgery: Skin lesions (SpC FM)
Keratosis = Growth of keratin on the skin or on mucous membranes stemming from ***keratinocytes, the prominent cell type in the epidermis (wiki) Seborrhoeic keratosis (Senile wart): - Benign - Old age - Pigmented, dry keratin (dead cell from the top layer of epithelium) - Rough surface - Raised - Does not bleed when cut open Actinic / Solar / Senile keratosis: - Premalignant (SCC) - Sun exposed - Does not bleed when cut - More living cells from deeper layers of epithelium Dermoid cyst: - Congenital: lateral eyebrow - Usually in midline?? - Looks like lipoma - Acquired: on hand due to trauma Sebaceous cyst (Epidermoid cyst): - From dermis layer, not able to pinch skin??? - Smooth not pedunculated - Half have punctum - Tense consistency Papilloma (aka Skin tag): - Prominent, round +/- pedunculated - If small, equivalent to skin tag - Fleshy, skin coloured - Living cells when cut, will bleed Neurofibroma: - Buttonhole sign - Tender, firm nodule, mobile laterally Dermatofibroma: - Buttonhole sign Mole / Nevus: - Can be raised - DDx: Melanoma, Seborrhoeic keratosis, BCC
37
Mucus retention cyst (SpC Revision)
- Obstruction of an excretory duct leading to back pressure of mucus + formation of an epithelium lined cyst - Minor trauma leading to rupture + escape of mucus into tissue —> recur afterwards - Smooth, transparent lesion
38
Choice of anaesthesia
Indications: - Biopsy / Examination / Surgery Local anaesthesia: - Small lesions - Superficial lesions - Single lesion - Cooperative patients - Prolonged operation / Complicated procedure Lignocaine (1% / 2% / +/- Adrenaline): - Max dose: —> Without adrenaline: 4 mg/kg —> With adrenaline: 7 mg/kg - Duration of action: ~1.5 hours —> May give additional dose 1% Lignocaine = 10 mg/ml Example: 60kg patient: - 1% lignocaine: 4 x 60 / 10 = 24 ml - 1% lignocaine with adrenaline: 7 x 60 / 10 = 42 ml Systemic toxicities: CNS: Early: - Tinnitus - Blurred vision - Dizziness - Tongue parasthesia - Perioral numbness Late: - Slurred speech - Drowsiness - Seizure - Respiratory arrest CVS: - Sinus bradycardia (prolonged PR, widened QRS) - Ventricular arrhythmia - Hypotension - Cardiac arrest Avoid systemic toxicities: - Proper injection: Avoid IV injection - Proper dosage Treatment of systemic toxicities: - Stop LA injection - Call for help - Airway - ***Control seizure by BDZ - Treat hypotension / bradycardia (CPR if pulseless) - ***20% lipid emulsion bolus (1.5 ml/kg) then infusion (0.25 ml/kg/min): Max dose: 12 ml/kg