Sandra Holgado

Correlation between Optical Coherence Tomography and glaucomatous optic nerve head damage in children

Aim: To compare analysis of macular and nerve fibre layer thickness by optical coherence tomography (OCT) with optic nerve head (ONH) morphology based on stereophotography. Design: Prospective observational case–control series. Methods: Normal and glaucomatous eyes of children (age 4–17 years) were scanned using Stratus OCT (Carl Zeiss Meditec, Dublin, California, USA). Fast macular and retinal nerve fibre layer (RNFL) thickness map were performed on 372 eyes of 222 children. ONH stereophotographs were taken and evaluated by two masked observers using a grading system of 0 to 5 based on both cupping ratio and morphology. OCT3 analyses were compared across ONH grades for different areas around the macula and the peripapillary RNFL. Results: Analysis included OCT values and ONH grading for 139 eyes of 139 children. There was a negative correlation between ONH grade and both macular thickness and RNFL thickness in all areas measured. There was a difference in the correlation identified for black versus white children. Conclusion: OCT measurements of RNFL and macular thickness declined with increasing grade of glaucomatous damage seen on stereophotographs in black and white children. Further study will help quantify the value of OCT in the diagnosis and management of paediatric glaucoma.

Management of ocular torsion and diplopia after macular translocation for age-related macular degeneration: Prospective clinical study

PURPOSE To report the results of a prospective clinical series to evaluate the management of both torsion and diplopia in a large group of patients after full macular translocation (FMT) and extraocular muscle surgery. DESIGN Prospective interventional case series. METHODS Information gathered included demographic, visual acuity, ocular motility, torsion by Maddox rod, ocular history, and symptoms of visual disturbance. Surgery on two, three, or four extraocular muscles was performed based on the magnitude of torsion measured after FMT surgery. RESULTS Fifty-three patients were included for both objective and subjective outcomes and were evaluated after FMT, both before (preoperative) and after (postoperative) extraocular muscle surgery. Preoperative torsion for two- (n = 6), three- (n = 8), and four-muscle (n = 39) surgery groups was 21.2 +/- 4.6, 30.0 +/- 6.3, and 40.5 +/- 8.7 degrees, respectively. At 6 months, postoperative residual torsion was significantly reduced in each group (to 3.4 +/- 3.2, 5.6 +/- 5.5, and 4.5 +/- 6.8 degrees, respectively, for two-, three-, and four-muscle groups). Muscle surgery reduced mean hypertropia from 17 +/- 6 prism diopters preoperative to 4 +/- 10 prism diopters postoperative (P <.0001); mean exotropia was mildly reduced from 20 +/- 9 prism diopters preoperative to 13 +/- 11 prism diopters postoperative (P <.01). Subjective data regarding diplopia and tilted vision after FMT and muscle surgery were available on an additional 10 patients (n = 53 + 10 = 63). Overall, 41% (26/63) of these were free of both diplopia and tilt, whereas only 5% (3/63) had both symptoms constantly. CONCLUSIONS Extraocular muscle surgery is effective at relieving the variable amounts of torsion produced by FMT when graded to match preoperative torsion. The majority of patients were free of disabling tilt and diplopia after extraocular muscle surgery.

FUNCTIONAL OUTCOMES OF YOUNG INFANTS WITH AND WITHOUT MACULAR EDEMA.

Purpose: The authors relate posterior segment microanatomy from perinatal spectral domain optical coherence tomography to visual acuity, brain abnormalities, and neurodevelopment. Methods: Thirteen infants (11 preterm and 2 term birth), imaged in the nursery with portable spectral domain optical coherence tomography, had visual acuity and sensorimotor testing at age 9 months to 15 months (grating acuity) or 4 years to 5 years (optotype), and medical records reviewed for brain magnetic resonance imaging reports and Bayley scales testing at age 18 months to 24 months. Results: Eight children with age-appropriate macular microanatomy without edema on perinatal spectral domain optical coherence tomography had optimal (≥20/40) or within normal limits (grating acuity) visual acuity. Five children with perinatal macular edema had suboptimal visual acuity (in 9/10 eyes) and sensorimotor deficits, magnetic resonance imaging abnormalities, or poor neurodevelopment. Macular edema persisted in 1 infant through 9-month corrected age. Conclusion: Maturation of the visual system and evolution of retinal anomalies can be monitored with posterior segment spectral domain optical coherence tomography. Retinal microanatomy observed in infancy might relate to subsequent vision and other central nervous system events, but additional studies are needed to determine the range of normal microanatomy in infants and how this relates to vision and neurodevelopment.

Optical coherence tomography in paediatric glaucoma: time domain versus spectral domain

Background/aims Spectral-domain (SD)- Optical Coherence Tomography (OCT) can track eye movements, has faster acquisition time and higher resolution than time-domain(TD)-OCT. The aim of the study was to assess the utility of SD-OCT in paediatric glaucoma and determine its agreement with TD-OCT. Methods Children who had SD-OCT(Spectralis, Heidelberg-Engineering,Germany) were retrospectively and prospectively identified from Duke paediatric glaucoma clinic. The peripapillary retinal nerve fibre layer (RNFL) and macular thickness and volume (MV) were compared amongst four groups: normal eyes, eyes with physiologic cupping (C:D >0.5 and <0.8, IOP <21), mild glaucomatous eyes (C:D <0.5, intra-ocular pressure (IOP) >21) and severe glaucoma (C:D>0.5, IOP>21). SD-OCT values were compared to TD-OCT(OCT-3, Carl-Zeiss-Meditec, Dublin, CA) values in a subset of subjects who had same day scans using both instruments. Children with neurologic disorders, refractive error >±5D, pseudophakia and prematurity were excluded. Results Included were 83 eyes of 83 children, mean age 11.9±4.2 years. SD-OCT measurements of average RNFL thickness and MV differed among normals(n=24), physiologically cupped (n=31), mild (n=15) versus severe glaucoma (n=13): (RNFL:104±9, 99±6, 98±9 vs62±18 µm, respectively, p<0.05; MV: 8.7±0.3, 8.6±0.3, 8.8±0.4 vs8.0±0.6 mm³, respectively, p<0.05). Same-day SD-OCT and TD-OCT measures in 53 eyes correlated linearly (RNFL r2=0.88; MVr2=0.58). SD-OCT measured lower RNFL and higher macular thickness than TD-OCT. Among eyes with severe glaucoma, 4 of 13 (30%) had unreliable TD-OCT but reliable SD-OCT. Conclusions SD-OCT was easier to obtain than TD-OCT in children. SD-OCT and TD-OCT measurements correlated, but values were not interchangeable.

Measurement of ocular torsion after macular translocation: disc fovea angle and maddox rod

PURPOSE To compare two methods of measuring ocular torsion (the subjective Maddox rod [MR] test versus the objective disc-fovea angle [DFA] test) after macular translocation surgery. METHODS Ocular torsion was measured on consecutive patients after macular translocation at Duke University Eye Center between August 2001 and April 2002. Both MR and DFA measurements of torsion were made at the same clinic visit 4 to 8 weeks after the translocation surgery and again within 3 months after extraocular muscle surgery to decrease torsion. MR and DFA measurements were each performed by a separate examiner who was blinded to the results of the other method. RESULTS Thirty-five patients (35 eyes) were included for evaluation. Twenty-nine of these patients had intorsion measured by both MR and DFA after macular translocation but before extraocular muscle surgery (MR mean of 40.3 + 7.2 degrees v DFA mean of 47.0 + 7.9 degrees [P <.001]). The intrapatient reproducibility of the MR test was high (using four readings per session), with a mean coefficient variation of 4.8%. Twenty-five patients had residual torsion measured by both MR and DFA after extraocular muscle surgery (MR mean of 4.2 + 4.7 degrees v DFA of mean 4.8 + 7.0 degrees). There was good correlation between MR and DFA measurements of torsion (r(2) = 0.9). CONCLUSIONS DFA measurement correlates well with MR measurement of torsion in patients after full macular translocation. This study verifies the reproducibility of MR to measure large angles of torsion and offers DFA as a simple corroborative test for measuring ocular torsion in patients with poor vision or cooperation.

Quantifying Vertical Angle Kappa After Macular Translocation Surgery: A New Use for the Synoptophore

Purpose: To report the measurement of vertical angle kappa and its application in patients after full macular translocation (MT360) and extraocular muscle surgery (to correct the resultant large angle torsion), in a prospective study. Methods: A custom slide was designed to quantify vertical angle kappa using the synoptophore. The measurement of the vertical angle kappa was performed in the eye that had the MT360, after the macular translocation surgery, extraocular muscle surgery (to correct torsion), and silicone oil removal, all in the same translocated eye. Information gathered included demographic, visual acuity, ocular motility, torsion, past ocular history, and synoptophore examination. Results: Fifty-three subjects met the inclusion criteria (patients who underwent upward MT360, with silicone oil tamponade and extraocular muscle surgery from 3/1999 to 6/2003, and who had visual acuity better than 20/200). Twenty-nine of these subjects were able to complete angle kappa measurement. The mean vertical angle kappa was 4.6 ± 1.4 degrees (n = 29) measured after MT360 and extraocular muscle surgery. The magnitude of vertical angle kappa did not correlate with either the amount of torsion after MT360, or the limitation of eye movement after both MT360 and extraocular muscle surgery. Conclusions: Vertical angle kappa can be measured using the synoptophore, and is increased above normal in eyes after MT360 and extraocular muscle surgery.

Diplopia after strabismus surgery.

The presence of diplopia is an undesirable result following strabismus surgery. There are a variety of scenarios where diplopia exists prior to strabismus surgery, and, after surgery, has been either alleviated or decreased to a magnitude amenable to prism correction. In other cases, the patient does not experience diplopia prior to the strabismus surgery, but there exists a definite risk of diplopia after the surgery. In the current review, I examine the literature to help determine the incidence of diplopia after strabismus surgery.