ξ Micro:
o Clusters of blue Basal Cells
o Basal cells are pleomorphic
o Burrows Deep into the Dermis
o “Palisading” appearance around the edge of the clusters of Basal cells (like
the walls of a palace)
③ Clinical Features:
ξ Excisional surgery : Still the gold standard treatment of BCC’s.
www.MedStudentNotes.com
DERMATOLOGY Pathology:
Procedural Dermatology – GP
Local Anaesthetic:
- Mechanism of Action:
o Use-Dependent blockade of Voltage-Gated Sodium Channels on Nerves
③ ⮴ Prevents Action Potential Conduction along Sensory Nerves.
o NB: Very Quick Onset of Action
o NB: Also causes vasodilation ⮴ Short Duration of Action (If without adrenaline)
- Lignocaine – Most Common:
o Rapid Onset (1-5mins)
o Medium (30-120mins)
o Max Dose: 4mg/kg
③ ≈ 50mL @ 1% Lignocaine
o (NB: 1% Lignocaine = 1g/1000mL)
- + Adrenaline:
o ⮴ Improves Haemostasis
③ ⮴ ↓Bleeding
o ⮴ ↓Systemic Absorption
③ ⮴ ↓Risk of systemic toxicity
③ ⮴ Prolonged Effect
o Max Dose: 7mg/kg (Higher Dose than without adrenaline)
o NB: DO NOT USE IN DIGITS OR PENIS (Or anywhere else with “End Arteries”)
o NB: DO NOT USE in LONG QT-Syndrome.
- Naropin (Ropivicaine):
o Longer onset of action
o Longer acting than lignocaine
o Max Dose: 2-3mg/kg
- Topical Anaesthetic:
o Xylocaine Gel - Useful for Mucosal Surfaces (eg. Oral Mucosa)
o ELMA Cream – Useful for topical anaesthesia of skin.
- Nerve Blocks:
o Digital Block (Ring Block)
③ (Most Common)
③ Blocks Digital Nerves
③ Use 2% Lignocaine (Because you want to inject as little as possible)
o Wrist Blocks:
③ Blocks Radial, Median, & Ulnar Nerves
③ ⮴ Totally anaesthetizes the hand.
Curettage & Electrocautery:
- Indications:
o Warts
o Keratoses
,o Molluscum contagiosum
o Curettes can also be used for curette biopsy.
- Wound Healing
o The curette wound can take some time to heal.
o If it is just a light curette such as tiny seborrhoeic keratoses with no cautery they can heal in a few days
o A full curettage and electrodessication on the trunk might take 4 to 6 weeks to heal www.MedStudentNotes.com
Cryotherapy:
- Cryotherapy is a very useful form of treatment for a number of benign skin lesions and few pre-malignant
and malignant skin lesions.
- Liquid Nitrogen = The gold standard
- Indications:
o Benign lesions:
③ Molluscum contagiosum
③ Seborrhoeic keratosis
③ Skin tags
③ Warts
o Premalignant lesions:
③ Actinic keratoses
③ Actinic cheilitis
o Malignant lesions:
③ Superficial BCC
- Effects of Cryotherapy – 3 Main Groups:
o 1. Those responses we expect to happen:
③ Pain on treatment and for a period afterwards
③ Oedema and swelling of the treated site and the surrounding tissue (e.g. periorbital
swelling after treatment of lesions on the forehead)
③ Vesicle and bulla formation
③ Exudation weeping and crust formation
o 2. Temporary Adverse Outcomes:
③ Hypopigmentation
③ Hyperpigmentation
③ Secondary Infection
o 3. Permanent Adverse Outcomes:
③ Permanent Hypopigmentation
③ Scarring + Possible Retraction
③ Allopecia
③ Nail Dystrophy
Biopsy Techniques:
o Clusters of blue Basal Cells
o Basal cells are pleomorphic
o Burrows Deep into the Dermis
o “Palisading” appearance around the edge of the clusters of Basal cells (like
the walls of a palace)
③ Clinical Features:
ξ Excisional surgery : Still the gold standard treatment of BCC’s.
www.MedStudentNotes.com
DERMATOLOGY Pathology:
Procedural Dermatology – GP
Local Anaesthetic:
- Mechanism of Action:
o Use-Dependent blockade of Voltage-Gated Sodium Channels on Nerves
③ ⮴ Prevents Action Potential Conduction along Sensory Nerves.
o NB: Very Quick Onset of Action
o NB: Also causes vasodilation ⮴ Short Duration of Action (If without adrenaline)
- Lignocaine – Most Common:
o Rapid Onset (1-5mins)
o Medium (30-120mins)
o Max Dose: 4mg/kg
③ ≈ 50mL @ 1% Lignocaine
o (NB: 1% Lignocaine = 1g/1000mL)
- + Adrenaline:
o ⮴ Improves Haemostasis
③ ⮴ ↓Bleeding
o ⮴ ↓Systemic Absorption
③ ⮴ ↓Risk of systemic toxicity
③ ⮴ Prolonged Effect
o Max Dose: 7mg/kg (Higher Dose than without adrenaline)
o NB: DO NOT USE IN DIGITS OR PENIS (Or anywhere else with “End Arteries”)
o NB: DO NOT USE in LONG QT-Syndrome.
- Naropin (Ropivicaine):
o Longer onset of action
o Longer acting than lignocaine
o Max Dose: 2-3mg/kg
- Topical Anaesthetic:
o Xylocaine Gel - Useful for Mucosal Surfaces (eg. Oral Mucosa)
o ELMA Cream – Useful for topical anaesthesia of skin.
- Nerve Blocks:
o Digital Block (Ring Block)
③ (Most Common)
③ Blocks Digital Nerves
③ Use 2% Lignocaine (Because you want to inject as little as possible)
o Wrist Blocks:
③ Blocks Radial, Median, & Ulnar Nerves
③ ⮴ Totally anaesthetizes the hand.
Curettage & Electrocautery:
- Indications:
o Warts
o Keratoses
,o Molluscum contagiosum
o Curettes can also be used for curette biopsy.
- Wound Healing
o The curette wound can take some time to heal.
o If it is just a light curette such as tiny seborrhoeic keratoses with no cautery they can heal in a few days
o A full curettage and electrodessication on the trunk might take 4 to 6 weeks to heal www.MedStudentNotes.com
Cryotherapy:
- Cryotherapy is a very useful form of treatment for a number of benign skin lesions and few pre-malignant
and malignant skin lesions.
- Liquid Nitrogen = The gold standard
- Indications:
o Benign lesions:
③ Molluscum contagiosum
③ Seborrhoeic keratosis
③ Skin tags
③ Warts
o Premalignant lesions:
③ Actinic keratoses
③ Actinic cheilitis
o Malignant lesions:
③ Superficial BCC
- Effects of Cryotherapy – 3 Main Groups:
o 1. Those responses we expect to happen:
③ Pain on treatment and for a period afterwards
③ Oedema and swelling of the treated site and the surrounding tissue (e.g. periorbital
swelling after treatment of lesions on the forehead)
③ Vesicle and bulla formation
③ Exudation weeping and crust formation
o 2. Temporary Adverse Outcomes:
③ Hypopigmentation
③ Hyperpigmentation
③ Secondary Infection
o 3. Permanent Adverse Outcomes:
③ Permanent Hypopigmentation
③ Scarring + Possible Retraction
③ Allopecia
③ Nail Dystrophy
Biopsy Techniques:
