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Trauma Suturing Techniques 7 Marian S Chapter 7 Trauma Suturing Techniques 7 Marian S. Macsai and Bruno Machado Fontes Key Points 7.1 Introduction • Assess the presence of life-threatening inju- ries. Ocular trauma is an important cause of unilateral vi- • Vision at the time of presentation and the sion loss worldwide, especially in young people, and presence or absence of aff erent pupillary de- surgical repair is almost always challenging [1–7]. A fect are important prognostic factors in the patient with an eye injury may need immediate inter- Ocular Trauma Classifi cation System [1]. vention, and all ophthalmologists who cover emergen- • Surgical goals include: cy patients must have the knowledge and skills to deal – Watertight wound closure with diffi cult and complex surgeries, as these initial ac- – Restoration of normal anatomic relation- tions and interventions may be determinants for the ships fi nal visual prognosis [7–15]. One must keep in the – Restoration of optimal visual function mind that the result of the fi rst surgery will determine – Prevention of possible future complica- the need for future reconstruction. tions Th e epidemiology of ocular trauma varies according • Surgical indications: to the region studied. In the World Trade Center disas- – Any perforating injury ter, ocular trauma was found to be the second most – Any wound with tissue loss common type of injury among survivors [16]. Th e – Any clinical suspicion of globe rupture re- most common causes of eye injuries include automo- quires exploration and possible repair tive, domestic, and occupational accidents, together • Instrumentation: with violence. Risk factors most commonly described – Complete ophthalmic microsurgical tray for eye injuries are male gender (approximately 80% of – Phacoemulsifi cation, vitrectomy and irri- open-globe injuries), race (Hispanics and African- gation and aspiration machines Americans have higher risk), professional activity (e. g., – Variety of microsurgical sutures military personnel), younger age (third decade), low • Surgical techniques: education, contact sports, and failure to comply with – Self-sealing wounds or lacerations <2 mm safety devices and equipment [1–3, 5, 6, 9, 16–19]. An- may not require surgical repair. terior corneoscleral lacerations, in sites of previous – Close perpendicular aspect of the wound ocular surgery, and posterior ruptures are more com- fi rst, the oblique aspect second. mon in the elderly as a result of frequent falls. – Avoid wound override. Any potentially life-threatening injury takes prece- – In the zigzag laceration a mattress suture dence over ocular injuries. Th e patient should undergo may be needed. a careful evaluation by qualifi ed emergency medical – In a stellate laceration a purse string may personnel and severe pain or nausea should be treated suffi ce. to decrease lid squeezing and Valsalva maneuver ef- – Extruded vitreous is a strong risk factor fects [4, 20–23]. Th e initial ophthalmologic evaluation for retinal detachment. is critical. Trauma mechanism and injury characteris- • An ideal initial surgical repair may eliminate tics according to the Ocular Trauma Classifi cation Sys- the need for future reconstruction. tem [1, 7] can predict the prognosis and fi nal visual • Monitor patient for postoperative complica- outcomes (Fig. 7.1). tions. Th e evaluation of initial visual function is the most • Long-term follow up indicated. important measurement by the initial as visual func- tion is directly related to visual prognosis, and is also important from a medicolegal perspective. Th e exam- iner should assess visual acuity with whatever equip- 62 Marian S. Macsai and Bruno Machado Fontes ment is available and this information must be docu- injuries. Topical ocular medications should be avoided mented in the patient’s chart. In addition, the examiner because of the risk of intraocular toxicity, and systemic should assess the pupillary refl ex with attention to the antibiotic prophylaxis should be started immediately. If presence or absence of an aff erent defect. A slit-lamp indicated, tetanus prophylaxis must be updated. assessment of the extent of the injury should deter- Simple self-sealing wounds or short lacerations (<2 mine if the cornea is lacerated and whether the lens is mm) with good tissue approximation, minimal gape, clear or opacifi ed. Any opacifi cation may indicate rup- no evidence of intraocular penetration, and no sign of ture of the lens capsule. Visualization of the posterior infection or necrosis can be managed with a bandage pole should be attempted, as the fi rst examiner may be contact lens and/or tissue adhesive (Fig. 7.2), in addi- the only one able to obtain a clear view of the posterior tion to topical broad-spectrum antibiotics, cycloplegic, segment and their fi ndings must be documented. and hypotensive drugs. With this approach the need for sutures is diminished, but patients must be closely THE OCULAR TRAUMA CLASSIFICATION followed. An eye shield must be placed, and the patient SYSTEM1 FOR OPEN-GLOBE INJURIES must refrain from any activity that results in a Valsalva maneuver. Th is is not a reasonable approach for chil- Type Grade dren and mentally disabled patients. A Rupture Visual acuity * As a general principle, a surgical plan should be B Penetrating 1. ≥ 20/40 made before surgery, including tissue conservation C Intraocular foreign 2. 20/50 to 20/100 and iatrogenic damage minimization. However, unex- body 3. 19/100 to 5/200 pected intraoperative situations can require a broad D Perforating 4. 4/200 to light spectrum of surgical techniques. To avoid delays dur- E Mixed perception ing the surgical procedure, the need for special equip- 5. No light perception† ment, such as a vitrectomy and/or phacoemulsifi cation Pupil Zone machine, should be determined previously. General Positive: relative aff erent I. Isolated to cornea anesthesia is preferred, as retrobulbar or peribulbar pupillary defect present (including the anesthesia may increase the intraocular pressure (IOP) in aff ected eye corneoscleral and risk extrusion of intraocular contents. Surgical Negative: relative limbus) closure should proceed in a timely manner to decrease aff erent pupillary defect II. Corneoscleral limbus the risk of endophthalmitis, avoid tissue necrosis and absent in aff ected eye to 5 mm posterior to decrease patient diskomfort [23]. the sclera Overall surgical goals in ocular lacerations include III. Posterior to the (1) watertight wound closure, (2) restoration of nor- anterior 5 mm of mal anatomic relationships, (3) restoration of optimal sclera visual function, and (4) prevention of possible future complications (e. g., glaucoma). * Measured at distance (20 ft , 6m) using Snellen chart or Th e overall goal is to restore the native corneal con- Rosenbaum near card, with correction and pinhole tour with minimal scarring. Corneal tissue should be when appropriate. † Confi rmed with bright light source and fellow eye well conserved as much as possible to avoid wound distor- occluded. tion or misalignment resulting in irregular astigma- Fig. 7.1 Ocular Trauma Classifi cation System 7.2 Surgical Indications Surgery is indicated when there is a risk of loss of nor- mal anatomic structure or function of the eye. Indica- tions include partial and/or full-thickness lacerations with aqueous leakage and intraocular tissue extrusion or prolapse. Surgery may be delayed by the patient’s Fig. 7.2 Technique to apply tissue adhesive to small lacera- medical condition, but is best performed as soon as tions. A broken wooden applicator with a small cuff of oint- possible to reduce the risk of complications (such as ment is adherent to a small polyethylene disk. Th e tissue glue endophthalmitis, tissue necrosis, and expulsive hemor- is on the opposite side of the polyethylene disk and is applied to the area of the laceration. Th e wound must be dry and free rhage). A rigid shield is indicated to protect the globe of epithelium for the adhesive to stick. Tissue glue will not from external pressure in all patients with open-globe adhere to a wet or epithelialized surface Chapter 7 Trauma Suturing Techniques 63 tism. If an avulsed piece of viable corneal tissue is pres- 7.4.1 ent, it should be sutured back into place. Any Suturing the Cornea anatomic landmark (such as pigmentation lines, scars, laceration edges, or the limbus) can help the surgeon A monofi lament suture (nylon or polypropylene) identify and restore the eye’s normal anatomy. Lacera- works well in the cornea, because of its low tissue reac- tions should be carefully explored to identify and re- tivity. Spatulated needles are preferred for maintenance move any foreign materials. Infection should be as- of suture depth in partial-thickness lacerations. Th e sumed, and the wound and any intraocular samples most stable confi guration of interrupted sutures is a should be submitted for culture and sensitivity. planar loop, so the tissue contained within the suture can be warped and distorted with inadequate suture tension. For proper placement, the tip of the needle 7.3 For proper placement, the placed perpendicular to the Instrumentation and Equipment corneal surface, and the needle is rotated through the wound along its curve, exiting perpendicular to the • Lid speculum cut surface. Corneal sutures should be 90% deep in the • Microsurgical 0.12-mm forceps stroma and of equal depth on both sides of the wound. • Microsurgical tying forceps (two) Full-thickness sutures may allow the suture material to • Nonlocking needle holder act as a conduit for microbial invasion. Suture passes • Vannas scissors should be approximately 1.5 to 2.0 mm in total length, • Iris hooks and the needle pass through the opposite side should • Cyclodialysis spatula mirror the initial needle pass in depth and length. Th is • Muscle retractors can be diffi cult in macerated and edematous tissue, • Viscoelastic and one must keep in mind the need to incorporate • Cellulose sponges healthy tissue in each suture pass, or else the sutures • Tissue glue (when applicable) will pull through the tissue when tied.
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