Outline
I. Basic Suturing Techniques in Primary Care Optometry
A. Clinical Applications
1. Adjustment and Removal of Interrupted and Continuous Sutures in Penetrating Keratoplasty
2. Lid Laceration Repair
3. Post chalazion incision and curettage (transcutaneous approach)
4. Suture Barb Removal after Cataract Surgery
5. Releasable Sutures in Glaucoma Filtering Surgery
6. Adjustable Sutures in Strabismus Surgery
B. Sterile Technique
C. Instrumentation for Suturing
1. Forceps
a) Tying
(1) Smooth platform to grasp needle without damage
(2) Provide secure contact when grasping suture material
b) Tissue
(1) Aid in handling of unstable wound edges
2. Needle Holders
Variations in Needle Holders
Smooth
Curved
Locking
Non-ratcheted
Grooved
Straight
Non-locking
Ratcheted
a) Clinical Pearls:
(1) Smooth platform can grasp needle at right angle or slightly obliquely
(2) Risk for damage to needle if platform is grooved
(3) Damage to needle more significant in continuous suture procedures
(4) Should not be used to grasp suture materials due to high forces that can damage delicate
suture material
(5) Excessive pressure by the needle holder may damage the needle and increase the risk of
needle bending or breakage
(6) Remember to apply the force to the needle along the direction of the curve of the needle
3. Needles
a) Degree of Curvature
(1) describes the shape of the needle and may vary from straight to 5/8 (of a circle)
¼ Circle
3/8 Circle
½
Circle
5/8
Circle
Straight
b) Cutting Profile
(1) The needle itself may have different profiles to the tip and the shaft
(2) Reverse cutting needles have a triangular profile
(3) Spatula needles allow the surgeon to view and control the depth of penetration of the needle
Reverse Cutting
Spatula
c) Clinical Pearls
(1) Diameter of the needle is generally measured in millimeters (mm)
(2) Needles may be sold separately from suture material or “swaged on” meaning that the suture
material is bonded to the needle
(3) Swaging reduces the thickness profile of the suture material to a single strand from a double
strand that is looped through the needle opening.
d) Needle Position
(1) Needle needs to engage the tissue vertically rather than obliquely
(2) Suture will rest within opening but if opening is oblique, then tissue can tear and the suture
can loosen
4. Sutures
a) Suture Characteristics
(1) Sutures vary in size from 10 to 1 and then 1-0 to 12-0 with 10 being the largest and 12-0 being
the smallest
(2) Characteristics include absorbable vs. non-absorbable, coated vs. uncoated, dyed vs. undyed,
monofilament, spun or braided, length of suture
Absorbable Suture Materials
Natural
Plain gut
Chromic cat gut
Synthetic
Polyglactin (Vicryl)
 Braided synthetic
 Handles like cat gut, knots securely
because of braiding
Polyglycolic acid (Dexon)
 Degrades slower, more predictably than
cat gut
Non-absorbable Suture Materials
Natural
Silk
 Silicone coated, braided
 Supple, strong, handles well
 Avoid in contaminated wounds due to
risk for abscesses particularly in skin
wounds
Linen
Cotton
Synthetic
Polyamide (Nylon)
 Difficult to tie monofilament, braided
preferred
Polypropylene (Prolene)
 Glides easily through tissue, similar to
monofilament nylon
 Polyester (Dacron)
Steel
 Hard to manage, kinks easily
D. Suture Techniques
1. Simple or Interrupted
a) Presses wound margins together
b) For small wounds e.g. short corneal incision
2. Mattress
a) Incisions through deep tissue e.g. lid procedures that involve skin muscle become depressed as
they heal due to vertical contracture of scar tissue
b) Mattress sutures help to evert the skin edges and close the wound
c) Slightly loose closure for these sutures helps to prevent a thickened hard scar than can occur
with a tight suture
3. Running or Continuous
a) For longer incisions or lacerations
b) Suture will not approximate skin edges as finely as interrupted suture
c) The entire suture will lose its strength if it breaks at any point along its length
d) Used in adjustable sutures for penetrating keratoplasty
4. The “Halving” Principle
a) To prevent wound gape
b) Initial suture is placed in middle of incision
c) Remaining sutures alternated to either side
E. Suture Tying
1. Surgeon’s Knot
a) The short end of the suture should be released
b) The long end of suture material is wrapped around the forceps one time in the opposite
direction to that used in the surgeon’s knot (single throw)
c) This knot is tightened securely but should not be over-tightened
d) Two or three additional knots should be tightened, each with a reversal in the direction of the
throw
2. Locking Knot
a) The short end of the suture should be released
b) The long end of suture material is wrapped around the forceps one time in the opposite
direction to that used in the surgeon’s knot (single throw)
c) This knot is tightened securely but should not be over-tightened
d) Two or three additional knots should be tightened, each with a reversal in the direction of the
throw
3. Burying the Knot
a) The knot should be pulled deeply into the canal.
b) The knot should then be reversed until it lies just under the surface to redirect the suture ends
pointing away from the surface to prevent later removal
F. Suture Removal
1. Method
a) Grasp the knot with forceps and lift gently away from the wound.
Using sharp, fine scissors, cut the suture just at the skin surface.
b) Pull the suture across the incision to remove it rather than away from the incision to prevent reopening the wound