1. Ocular oncology Dog eyelid masses
Presented by Rosalie Atkins, DACVO

2. Eyelid Masses- Neoplasia Chalazion Blepharitis How to excise
Cryotherapy
Laser
Chalazion
Blepharitis
Infectious
Bacterial
Fungal
Parasitic
Immune mediated
Infectious Blepharitis
Bacterial Blepharitis
Meibomianitis
Blepharomycosis
Parasitic Blepharitis

3. Neoplastic Eyelid Masses
Meibomian gland adenoma, adenocarcinomas, epithelioma, melanoma
Generally clinically benign
20-30% histologically malignant
Treatment
Monitor
Growth, rubbing, discomfort/ squinting, ulceration
Surgical excision
~30 month mean recurrence rate
Cryotherapy
~8 month recurrence rate
CO2 laser
AVMA 1986 Prevalence and treatment of palpebral neoplasia in the dog

4. Eyelid Surgery Basics Clip/clean 1/3-1/4 of the lid Lid margin
Upper and lower puncta
4-0, 5-0 or 6-0 suture
E-collar
Antibiotics
Palpebral fissure length ,
Cat 28 mm with persians being slightly longer
Paper from stades in 1992
You can take 25-33% of the lid

5. Wedge Resection 2 sided wedge:
The V or 2 sided wedge involves cutting the meibomian glands obliquely.
The eyelid margin is then aligned, closed with a figure eight. The remaining skin incision is closed in simple interrupted with monofilament or silk sutures.

6. 4-Sided Excision 4 sided wedge: Technique:
Parallel incisions are made perpendicular to the eyelid margin 2 to 3 mm away from the mass extending just beyond the dorsal (ventral) extent of the tumor. Converging incisions are then made from the end of the parallel incision to a point dorsal (ventral) to and 1 to 2 mm beyond the mass. A two-layer closure is performed.

7. Pre-op

8. Identify Upper Punctum

9. Perpendicular and Converging

10. Perpendicular and Converging

11. Finished Excision

12. Closure- Muscle/ Tarsus

13. Closure- Finished Closing Tarsus

14. Closure- Eyelid Margin- Figure 8
Make sure have correct suture
6-0
5-0
Maybe 4-0

15. Closure- Eyelid Margin- Figure 8

16. Closure- Eyelid Margin- Figure 8

17. Closure- Eyelid Margin- Figure 8

18. Closure- Finished Figure 8

19. Closure- Skin- Simple Continuous

20. 8 Days Post-op

21. 8 Weeks Post-op Lateral canthotomy to help close Complications Suture
Ectopic or misdirected hair
ulceration

22. Complications- Suture Rub

23. Complications- Suture Rub

24. Complications

25. Cryotherapy Tissue destruction Freezing Thawing Ice crystals
Rate of freezing and thawing
Vascular stasis
Thrombosis
Antigenic release
Antibody production
Freezing
Slow
large extracellular
Fast
Intracellular
Thawing
Enhances recrystalization
Cryoadhesion -20 to 40
Cryonecrosis -70

26. Cryotherapy Liquid nitrogen -195 C Nitrous oxide -89C
Spray
Probe
Poured
Nitrous oxide -89C
Probe only
Probe line pressure mmHg
Tissue temperature
-20C
Probe temperature
-70C

27. Cryotherapy Temperature PROCEDURE Tissue temperature Probe temperature
Clamp
Debulk mass
2-3 freeze thaw cycle
1 min per freeze
3 mm beyond edge of mass
80%

28. CO2 laser- Light Amplification by Stimulated Emission of Radiation
Main Biological targets
Blood
Melanin
Water
All tissues have water
Converts water to vapor and gas
Ablation
Periphery
Coagulation of small vessels
Large vessels bleed

29. CO2 laser- Safety Glasses- glass or plastic
Cornea absorbs energy
Wet gauze or tongue depressor
Smoke evacuator

30. references Gelatt and Gelatt, Veterinary Ophthalmic Surgery, 2011
Veterinary Ophthalmology (2016) 19, Supplement 1, 44–55
Veterinary Ophthalmology (2010) 13, 6, 391–394
Veterinary Ophthalmology (2008) 11 , 6, 401–405
The Use of cryosurgery in a veterinary ophthalmology practice
The role of the CO2 laser and fractional CO2 laser in dermatology