Preoperative Considerations
Amanda L. Ely, MD
Sharon F. Freedman, MD
PREOPERATIVE CONSIDERATIONS
In an eye with suspected pediatric glaucoma, a full ocular examination is essential to confirm the specific pediatric glaucoma diagnosis, to obtain baseline ocular measurements that will be helpful for future disease management, and to determine which medical and/or surgical therapies are most appropriate to maximize long-term IOP control.
Which Type of Pediatric Glaucoma Does Your Patient Have?
Determining the specific pediatric glaucoma diagnosis is essential in order to:
Counsel the family appropriately on long-term outcomes.
Determine which medical and/or surgical therapies are indicated (Fig. 9.1).
When Is Glaucoma Surgery Necessary? Consider Surgery in Patients With:
Primary congenital glaucoma (PCG).
Closed angle glaucomas (eg, cicatricial retinopathy of prematurity).
Progressive IOP-related ocular damage despite maximal tolerated medical therapy.
SURGICAL PLANNING
Manage patient/parent expectations about the following:
Chronic disease management and follow-up.
Loss of IOP control can occur even decades after successful glaucoma surgery.
Guarded visual prognosis.
Likely need for further surgical intervention, including further glaucoma surgery, possible strabismus surgery, and/or possible cataract surgery.
Likely need for further medical intervention, including chronic eye drops, glasses, and amblyopia therapy.
FIGURE 9.1. Classification of childhood glaucomas. Childhood Glaucoma Research Network (CGRN)-World Glaucoma Association algorithm for the classification of childhood glaucoma. IOP = intraocular pressure; ONH = optic nerve head; VF = visual field. (Adapted from Childhood Glaucoma Research Network, courtesy of Ta Chen Peter Chang.)1
Ensure that you have the following equipment/medication:
Days to weeks in advance:
Specific glaucoma drainage device (GDD) implants (eg, Ahmed FP7 or FP8, Baerveldt 250 or 350) (see Chapter 11).
Specific patch graft tissue (eg, sclera, cornea).
Special order disposable equipment (eg, illuminated catheter for trabeculotomy, goniotomy lens).
Same day:
Special pre-op or intraoperative medications (eg, pilocarpine 1% or 2%, apraclonidine 0.5%, sodium chloride 5%, timolol 0.25%, mitomycin C, subconjunctival antibiotic or steroid).
Special equipment (eg, Retcam, B-scan ultrasound, anterior chamber maintainer, specific surgical gonioscopy lens).
Specific orientation of the microscope (eg, tilt for goniotomy).
Preoperative medications (to help lower IOP and to clear the cornea preoperatively to facilitate goniotomy), ideally used days before the planned surgery. Consider punctal occlusion in infants to reduce systemic absorption.
Beta blocker (eg, timolol 0.25% once daily):
Typically first-line and safe for use in infants and toddlers <35 lb.
Use with caution, if at all, in those with history of respiratory disorders (eg, asthma, apnea of prematurity).
Carbonic anhydrase inhibitor (eg, dorzolamide 2% three times daily):
Second line if beta blocker use contraindicated.
Caution in neonates <35 weeks postmenstrual age because of the risk for metabolic acidosis.
Sodium chloride 5%:
Use in conjunction with IOP lowering medications to help lessen corneal edema.
EXAMINATION UNDER ANESTHESIA (EUA)
The EUA is necessary to obtain information that cannot be obtained in the clinic setting. EUA can be performed separately or in conjunction with planned glaucoma surgery.
