Mohs Surgery

Question 1

what is the formula for calculating the area of a circle?

Answer 1

3.14 x Radius squared

Question 2

In a sharply demarcated lesion of .6 to 1.9 cm of BCC or SCC what margin gives 95% clearance?

Answer 2

4mm

Question 3

In a poorly defined lesion of .6 to 1.9cm of BCC or SCC what margin gives 95% clearance?

Answer 3

5mm

Question 4

For Basal and SCC what area is high risk independent of tumor size?

Answer 4

Area H

Question 5

Ankles fall in what area

Answer 5

Area H

Question 6

nipples fall in what area

Answer 6

Area H

Question 7

Genitalia fall into what area

Answer 7

Area H

Question 8

Sebaceous carcinoma of .5 cm on chest does this met Mohs criteria?

Answer 8

Yes, any size all areas HM and L

Question 9

Angiosarcoma has appropriate use criteria in what areas

Answer 9

None. It is uncertain in all areas

Question 10

What areas can you treat bowenoid papulosis by Mohs

Answer 10

No appropriate use criteria for bowenoid papulosis

Question 11

Where can you treat Desmoplastic Trichoepithelioma by Mohs.

Answer 11

Uncertain H and M no in L

Question 12

Can you treat a Merkel cell carcinoma on the arm by Mohs.

Answer 12

It is uncertain in that location. Everywhere else yes

Question 13

Of the following which can be treated by Mohs any size any HML location.
Extramammary paget’s disease
DFSP
Atypical Fibroxanthoma

Answer 13

all of them

Question 14

what are three features of cautery artifact

Answer 14

spindled nuclei
palisading
separation of the epi and basement membrane

Question 15

If you have bcc enter the orbital fat pad with BCC what should you do?

Answer 15

Stop, order MRI (soft tissue involvement) and CT (bony involvement) consult with radiation oncology and oculoplastics

Question 16

Under what circumstances is it appropriate to use Mohs surgery in treating a superficial BCC in area L

Answer 16

There are no indications for treating superficial BCC by Mohs surgery in area M.

Question 17

What is chatter in a Mohs section.

Answer 17

alternating thick and thin sections in the cut which can be parallel or perpendicular to the cutting edge.

Question 18

List 7 reasons for chatter in a Mohs section.

Answer 18

1. block only unevenly frozen
2. cutting speed too fast
3. calcification
4. dull or nicked blade
5. blade clearance to high or tilted
6. inadequate tightening of gears or lubrication
7. unsteady hand when doing the cut.

Question 19

Name three scenarios that may increase the risk of floaters that happen in 2% of Mohs cases.

Answer 19

BCC, ulcerated tumors, and within the first layer of Mohs surgery

Question 20

what component in anesthetics may increase bilirubin in the blood by binding with albumin and displacing the bilirubin, esp in folks with hyperbilirubinemia.

Answer 20

The preservative contains methylparaben which does this action.

Question 21

How long can buffered lidocaine last in the bottle and remain effective.

Answer 21

2 to 8 weeks