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Sclera and Retina Suturing Techniques 9 Kirk H Chapter 9 Sclera and Retina Suturing Techniques 9 Kirk H. Packo and Sohail J. Hasan Key Points 9. 1 Introduction Surgical Indications • Vitrectomy Discussion of ophthalmic microsurgical suturing tech- – Infusion line niques as they apply to retinal surgery warrants atten- – Sclerotomies tion to two main categories of operations: vitrectomy – Conjunctival closure and scleral buckling. Th is chapter reviews the surgical – Ancillary techniques indications, basic instrumentation, surgical tech- • Scleral buckles niques, and complications associated with suturing – Encircling bands techniques in vitrectomy and scleral buckle surgery. A – Meridional elements brief discussion of future advances in retinal surgery Instrumentation appears at the end of this chapter. • Vitrectomy – Instruments – Sutures 9.2 • Scleral buckles Surgical Indications – Instruments – Sutures Surgical Technique 9.2.1 • Vitrectomy Vitrectomy – Suturing the infusion line in place – Closing sclerotomies Typically, there are three indications for suturing dur- • Scleral buckles ing vitrectomy surgery: placement of the infusion can- – Rectus muscle fi xation sutures nula, closure of sclerotomy, and the conjunctival clo- – Suturing encircling elements to the sclera sure. A variety of ancillary suturing techniques may be – Suturing meridional elements to the sclera employed during vitrectomy, including the external – Closing sclerotomy drainage sites securing of a lens ring for contact lens visualization, • Closure of the conjunctiva placement of transconjunctival or scleral fi xation su- Complications tures to manipulate the eye, and transscleral suturing • General complications of dislocated intraocular lenses. Some suturing tech- – Break in sterile technique with suture nee- niques such as iris dilation sutures and transretinal su- dles tures in giant tear repairs have now been replaced with – Breaking sutures other non–suturing techniques, such as the use of per- – Inappropriate knot creation fl uorocarbon liquids. • Vitrectomy – Complications associated with sclerotomy closure 9.2.2 ■ Intraoperative Scleral Buckles ■ Postoperative • Scleral buckles Suturing during scleral buckle surgery involves place- – Complications associated with suturing to ment of rectus muscle fi xation sutures, securing encir- the sclera cling elements, securing meridional elements, tying – Complications associated with suturing the ends of encircling elements, closing sclerotomy conjunctiva drainage sites, and closing the conjunctiva. Future advances and alternatives to sutures • Vitrectomy • Scleral buckles 86 Kirk H. Packo and Sohail J. Hasan 9.3 with Vicryl, 9.3% close with a synthetic monofi lament, Instrumentation 0.5% close with plain gut, and 1.3% close with another suture type [17]. Conjunctival sutures are most com- monly plain gut, and may have either spatula or taper- 9.3.1 tip styles. Some surgeons conserve resources by using Vitrectomy the same suture to close the sclerotomies as the con- junctiva. Th e scissors chosen to cut the stitches are ei- Instrumentation required for suturing during vitrec- ther the Westcott scissors typically used for the con- tomy includes caliper, forceps, needle holder, suture, junctival opening or a separate dedicated sharp-tip and scissors. Calipers can be in a wide variety of styles. stitch scissor. Cutting large sutures such as a 5-0 Mer- We have found a fi xed caliper of 4.0 and 3.5 mm at al- silene should be done with larger tips, and more deli- ternate ends to be the most useful for vitrectomy. Th e cate scissors such as Vannas style should be avoided. two tissues involved with suturing during vitrectomy are the conjunctiva and sclera. Th e fi xation forceps chosen to handle each tissue are by surgeon prefer- 9.3.2 ence. We prefer to use a non-toothed ring forceps Scleral Buckles (ASICO, Chicago, Ill.) to manipulate conjunctiva. Th e ring tip provides an excellent grasp of the conjunctiva Th e surgical instruments required for suturing during while minimizing bleeding. For scleral fi xation, either scleral buckle surgery include caliper, forceps, scissors, 0.12-, 0.3-, or 0.5-mm toothed forceps, or 0.1-mm muscle hooks, needle holders, sutures, and retractors. Maumenee-Colibri forceps can be used to grasp the Th e same fi xation forceps and needle holders described sclera. Th e larger toothed forceps are useful for general for vitreous surgery have utility in scleral buckling. scleral fi xation, whereas the smaller-toothed varieties Th e suture choice to fi x an episcleral implant varies, are useful for grasping the cut edge of sclera as in scle- again, by surgeon preference and training. A spatula rotomy closure. We fi nd that Maumenee-Colibri for- needle is universally chosen to ensure more depth con- ceps are particularly useful because of their angle and trol within scleral lamellae. Th e two most commonly small tooth size, which provides an excellent grasp of utilized suture materials are either a 5-0 nonabsorb- the cut scleral edges. Needle holders are chosen by sur- able nylon suture or a 5-0 nonabsorbable soft suture geon preference. Design choices include platform size, such as polyester Mersilene. Th e advantage of nylon is locking versus non-locking, and straight versus curved. that its stiff memory holds the knot between throws Because running and fi gure-of-eight sutures are com- and does not loosen as easily as does Mersilene. In ad- mon, we have found straight locking holders to be the dition, studies have shown less infl ammatory reaction most useful. to nylon than to synthetic braided sutures, following Suture choices also vary by surgeon preference. Th e chronic implantations in infected experimental spatula-tipped needle was fi rst introduced by Lincoff wounds [24]. A Schepens-style orbital forked retractor in the 1960s and was a great advance for scleral sutur- or the de Juan retractor works very well to help visual- ing. Th e side cutting design allows the needle to pass ize sclera for suturing [3]. A custom-designed illumi- within the scleral lamellae rather than across them, ma- nated orbital retractor is useful in visualizing the scler- king tissue depth more constant throughout the pass. al surface in deep or tight orbits. Th e ends of an Several options exist for the infusion line cannula re- encircling band can be secured with a clove hitch non- tention suture. A 5-0 Mersilene polyester fi ber suture absorbable suture [1], tantalum clip [7], or silicone with a spatula needle can be used to temporarily fi x the sleeve [25]. cannula, and is later removed completely at the end of the case. Alternatively, a 7-0 Vicryl suture can be placed in a fi gure-of-eight fashion (see Sect. 9.4 below) to se- 9.4 cure the infusion cannula. If temporarily tied, this Surgical Technique same suture can be loosened and used to close the scle- rotomy site at the end of the case. Another option for Retinal surgeons should exercise basic surgical princi- sclerotomy site closure is to use a 9-0 or 10-0 synthetic ples that are universal to all ophthalmic suturing tech- monofi lament suture, such as nylon or Prolene. Mono- niques. Th ese include: fi lament nylon sutures are elastic, and close wounds 1. Always manipulate needles with instruments and that have opened as a result of undue pressure on the never with the gloved hand. Holding needles with globe [2]. For this reason, completely sutures (such as the fi nger tips is quick and oft en tempting, but runs silk) should not be used. In a survey of 398 retinal sur- the risk of accidental perforation of the glove tip. geons by the American Society of Retina Specialist in Th is perforation is oft en unrecognized and breaks 1999, 86% of surgeons prefer to close sclerotomies sterile technique. Chapter 9 Sclera and Retina Suturing Techniques 87 2. Never grasp a needle tip with the pick-up forceps. 9.4.1 Needles should be grasped and held only with nee- Vitrectomy: Suturing of the Infusion Line dle holders. When repositioning the needle on the holder, it should be done by holding the suture Using a caliper, a mark is placed in the inferotemporal rather than the needle with the pick-up forceps near quadrant 4 mm from the limbus in phakic eyes or where the suture is swedged into the needle. Th is 3.5 mm from the limbus in pseudophakic eyes below technique protects the fi ne teeth of the forceps. the horizontal, avoiding placement that would injure 3. Always match the needle holder platform size with the long ciliary artery and nerve at the direct horizon- the needle, and match the size of the scissors to the tal (Fig. 9.1a). Th e eye should be fi xated immediately size of the suture being cut. For example, cutting adjacent to where the suture will be passed using fi ne- 2-0 silk traction sutures with fi ne Vannas scissors toothed forceps. Fixating on the opposite side of the will damage the scissor tips. Holding a large needle globe allows “scissoring” of the eye as the needle is with too fi ne a needle holder allows less control passed and loss of control. and may also damage the holder. Th e suture passes should be parallel to the limbus at 4. Always unlock a locking needle holder prior to en- least one half to three quarters of scleral depth and tering the tissue with the needle pass. Th is allows a should straddle the caliper mark. For a right-handed simple open release at the completion of the pass, surgeon, the fi rst pass should be to the right of the and obviates the squeeze to release the lock while caliper mark regardless of the eye being operated on. the needle is embedded into the tissue, possibly Th e fi rst pass for a left -handed surgeon should be to contributing to tissue tearing or inadvertent pene- the left of the mark.
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