COMPARISON OF 2 ANAESTHESIA TECHNIQUES FOR PEDIATRIC
REFRACTIVE SURGERY
Magraby Eye and Ear Centre - OMAN
Background Difficulties with children and LA
Reports of NO2 interference with Laser function
Aim – compare propfol/fentanyl and ketamine/midazolam
Method
Prospective 30 patients Randomized to 2 groups Age 3 to 12 years Aniso/Amblyopia
Method
NBM overnight
Clear fluids till 4 hours before
LASIK or LASEK
Monitoring
Heart rate
MABP
SaO2 O2 by nasal cannula if SaO2 ≤ 90%
Results
Matched for: age weight duration of anesthesia duration of surgery
Results Time to recovery shorter in P/F group Opposite effects on BP and HR P/F group 3 patients needed O2
Post-op agitation and vomiting higher in K/M group
Airway obstruction (needing jaw thrust) higher in P/F group
Ophthalmologist satisfaction
Bells phenomenon Nystagmus Overall intra and post-op state
No significant difference (used suction ring for fixation)
Conclusions
Propofol preferred Shorter acting Lower incidence of dysphoric effects Greater potential for airway compromise.
PRK AND LASIK IN ACCOMMODATIVE ESOTROPIA
University of L’Aquila, Italy
Methods Prospective 18 consecutive patients Mean age 32.4 (range 21 to 52) Accommodative eso (normal AC/A) No suppression 8 – PRK (Group A) 10 – LASIK (Group B)
Pre-op – Group A Without correction ET’ 14.4 ∆ (10 to 19) ET 11.6 ∆ (8 to 14)
With correction ET’ 5 ∆ (4 to 6) ET 2.4 ∆ (2 to 4)
Mean 71.2 sec/arc
30 days in CL 2∆ esophoria – near 1.2 ∆ esophoria – distance
Refraction +4.6 D (mean) (range +3.50 to +6.00)
Mean BSCVA – 20/20
Post –op results 1 Year ET’ 1.2 ∆ esophoria ET – orthophoric
2 Years ET’ 2 ∆ esophoria ET 0.4 ∆
Pre-op Group BWithout correction ET’ 13.4 ∆ (8 to 21) ET 11.5 ∆ (6 to 19) With correction ET’ 5.4 ∆ (2 to 8) ET 2.8 ∆ (orthophoria to 6)
Mean 81 sec/arc
30 days in CL 2.5 ∆ esophoria – near 1.1 ∆ esophoria – distance
Refraction +6.46 D (mean) (range +5.00 to +8.50)
Mean BSCVA – 20/20
Post –op results 1 Year ET’ 1.7 ∆ esophoria ET 0.2 ∆ esophoria
2 Years No change
Only 1 case of regression Recurrence of ET
Essentials to success Good binocular function
Good acuity
Careful selection of patients
? Timing of surgery
Possible application to older children and young adults?????
REFRACTIVE SURGERY FOR CHILDREN
Review by L.Tychsen
Corneal surface ablation
Phakic IOL
Clear Lens Exchange
Who Anisometropia – spectacle non-compliant 2.0 D - hypermetropes 3.0 to 4.0 D - myopes
Intolerance of specs or CL
Neuro-behavioural disorders
Who Iso-ametropia Spectacle non-compliant Amblyopia approaching 50%
Neuro-behavioural disorders Visual autism
Who
Other special needs Craniofacial deformities
High hyperopia and esotropia Poor spectacle compliance
Strategy Baseline Repeated examinations EUA
Surface ablation +6.0 to -10.0 D ACD ≥ 3.2 mm Phakic IOL Remainder - Clear lens extraction
Surface ablation Volatile induction Intravenous anaesthetic EUA LASEK or PTK/PRK BCL and goggles Epithelial healing as in adults Better tolerated
Phakic IOL Artisan iris enclaved Bilateral sequential – 1 month interval Absorbable sutures Limbal relaxing incisions Arm band restraints
Refractive lens exchange Above 20.0 D ACD ≤ 3.2 mm Lensectomy Posterior capsulectomy Anterior vitrectomy Acrylic IOL AL ≥ 29 mm - Prophylactic laser
Efficacy
Improvement in UCVA
Best with bilateral ametropia
Modest with anisometropia
Results - Surface ablation
Ametropia avg 7.1 D
UCVA 20/180 to 20/60 (mean)
If glasses worn - BCVA 2-fold improvement
Results – Phakic IOL Ametropia – mean 15.0 D
UCVA 20/3400 to 20/57 (mean)
Similar results with CLE
Surface ablation and Anisometropia
90% within 1.5 D of emmetropia
Variable improvement in UCVA and BCVA
No reported loss of acuity
50% improvement in fusion and stereopsis
Complications Low
Several years follow up
Small numbers
Surface ablation 260 eyes - 1998 to 2008 Negligible rate of sight-threatening
complications LASIK – flap complications LASEK – thicker residual stroma Regression - 1.0 D/year ? Over-correction for myopes
Phakic IOL No regression
Corneal endothelium? Low rate of loss
? Posterior chamber IOLs
? Glaucoma/ Cataract
Clear lens extraction Accomodation Multifocal IOLS? RD risk – 3% long term
Conclusions
Substantial benefits for selected patients
Need more information/scrutiny/disclosure