Association of orbital decompression and the characteristics of subsequent strabismus surgery in thyroid eye disease

OBJECTIVE

To examine the association of orbital decompression and the characteristics and outcome of subsequent strabismus surgery in patients with thyroid eye disease (TED).

METHODS

Data on patients with TED who underwent orbital decompression at the Goldschleger Eye Institute, Sheba Medical Center, Israel, between January 1990 to December 2011 were extracted. The characteristics of decompression and strabismus surgeries were recorded. The outcomes and association of both surgical procedures were analyzed. Statistical analysis included distribution, Pearson correlation, and matched paired tests.

RESULTS

145 eyes underwent orbital decompression, of which 45 eyes (31.0%) underwent strabismus surgery. Esotropia developed in 70% of the patients. Men and smokers underwent strabismus surgeries after decompression procedures more frequently than women and nonsmokers (χ² test, p = 0.07, 0.002). Moreover, patients who complained of diplopia before the decompression surgery underwent strabismus surgery more frequently (χ² test, p = 0.005). Seventy-seven percent of the patients who underwent medial wall decompression developed esotropia (χ² test, p = 0.004).

CONCLUSIONS

To the best of our knowledge, this is the largest series in the literature examining the association between decompression and strabismus surgeries. The patients' characteristics and the orbital walls involved in the decompression procedures are associated with the characteristics of subsequent strabismus that develops thereafter. These findings may have significant implications in planning TED management.

A comparison of plusoptiX A12 measurements with cycloplegic refraction

PURPOSE

To test the accuracy and reliability of the plusoptiX A12 in detecting amblyogenic risk factors.

METHODS

We prospectively collected data on children undergoing screening with the plusoptiX A12, cycloplegic refraction, and complete ophthalmic examination. American Association for Pediatric Ophthalmology and Strabismus (AAPOS) 2013 guidelines for the detection of amblyogenic risk factors were used for plusoptiX A12 screening and comparison of the results of both examination modes.

RESULTS

Data on 402 eyes of 201 children (mean age, 7.63 ± 3.41 years) was collected. Mean (with standard deviation) cycloplegic refraction results were as follows: sphere, 0.88 ± 1.5 D; cylinder, -0.61 ± 0.74 D; axis, 71.17 ± 71.04; and spherical equivalent, 0.68 ± 2.63. The plusoptiX A12 measurements were as follows: sphere, 0.58 ± 1.4 D; cylinder, -0.66 ± 0.77 D; axis, 77.3 ± 68.9; and spherical equivalent, 0.25 ± 1.3. We found a strong correlation (Pearson) for sphere (r = 0.91), cylinder (r = 0.81), and axis (r = 0.7). The mean difference of the myopic spherical component between the plusoptiX and cycloplegic refraction was -0.048 ± 0.55 (95% LoA, +1.04 to -1.14 D); for the hyperopic spherical component, 0.37 ± 0.93 (LoA, +2.20 to -1.45 D); and for the cylindrical component, 0.05 ± 0.32 (LoA, +0.68 to -0.57D). The sensitivity, specificity, positive and negative predictive values for myopia were, respectively, 86%, 93%, 82%, and 94%; for astigmatism, 85%, 98%, 88% and 98%; and for hyperopia, 40%, 100%, 100%, and 98%.

CONCLUSIONS

The plusoptiX A12 accuracy is high in all subgroups but better in the myopic, astigmatic, and anisometropic subgroups. Reliability was lower in the hyperopic eyes, possibly resulting in underestimation of hyperopic refractive error.

Measurement of Axial Length in an Office Setting Versus Under General Anesthesia in Infants and Toddlers: A Comparative Study

PURPOSE

To examine whether axial length measurement in awake infants and toddlers is feasible, and whether there is a difference in axial length measurement between an office setting and under general anesthesia.

METHODS

This prospective comparative case study was conducted at the Goldschleger Eye Institute, Sheba Medical Center, Israel. Using the same instruments, axial length measurements were obtained using a standard applanation technique twice: once in an office setting when the infant/toddler was awake and once under general anesthesia in the operating room. A paired t test was used to test for differences between measurements.

RESULTS

Thirty-three eyes of 19 participants younger than 28 months were examined; 24 (73%) eyes had cataracts and the remainder had clear lenses. One child was excluded from the study due to lack of cooperation during axial length measurement in the office setting and another due to the lengthy gap between measurements. Of the remaining 31 children, the average age was 9 months. Average axial length measurements were shorter by 0.12 mm in the office setting than under general anesthesia (P = .14). No adverse effects were observed after axial length measurements in the office setting.

CONCLUSIONS

Axial length measurement in an office setting is generally reasonable to obtain. The results showed no significant difference in the axial length measured in the two settings.

[The rate of development of myopia during hyperbaric oxygen therapy]

BACKGROUND

Hyperbaric oxygenation (HBO) is a common treatment both for emergency medicine as well as for chronic treatments. One of the most common indications for treatment is a non-healing wound due to diabetes. It is known that prolonged HBO treatments cause a myopic change in refraction. From the literature we know that the myopic shift is usually temporary, reversing back to basic refraction within a few weeks of cessation of the HBO course. There is controversy in the literature regarding the cause of refraction change, but research with animals reinforces the view that the source is the lens nucleus.

PURPOSE

To measure the refractive change following 30 HBO treatments, and to quantify the rate of change.

METHODS

A prospective study that included 44 eyes of diabetic patients treated with HBO in Rambam and Elisha Hyperbaric Center. Follow-up examinations were carried out every 10 treatments for spherical equivalents, sphere components, cylinder powers and axes (SPHER, SE, CYLINDER and AXIS respectively). The measurement device was an autorefractometer. A single examiner performed all the measurements; the examiner was blinded to the previous results. For each parameter, a regression equation was calculated after plotting the myopic change over time.

RESULTS AND CONCLUSIONS

A positive correlation was found between HBO treatments and a myopic shift in the refraction. The correlation was statistically significant for: SPHER, SE. (0.58D, 0.61D) respectively. The change accrued from the first examination and remained throughout the follow-ups at a steady rate. Both eyes behaved similarly. The authors did not find a correlation between the myopic shift and gender, age or basic refraction. This information is vital both to clinicians, to understand the physiologic changes occurring during chronic HBO treatments, and especially to our patients, who are about to receive HBO treatments.

Refractive outcomes with secondary intraocular lens implantation in children

PURPOSE

To determine the accuracy of postoperative predicted refractive outcomes in surgically aphakic pediatric patients undergoing secondary intraocular lens (IOL) implantation. Comparisons were also made with other variables historically considered important in cataract surgery.

METHODS

Retrospective review of 50 eyes from 35 consecutive pediatric patients (< or =18 years of age) undergoing secondary IOL implantation within the ciliary sulcus or posterior capsular bag. All cases were performed by 1 of 2 surgeons and all refractions were performed manually using the retinoscope by an experienced pediatric ophthalmologist.

RESULTS

The mean patient age at the time of the secondary implantation was 6.5 years of age (range, 0.58-15.04). The mean patient age at the time of the primary cataract extraction was 0.78 years (range, 0.08-5.77). For all patients, mean absolute value of prediction error was 1.64 D (SD 1.58 D). There were no significant associations between mean absolute value of prediction error and any of the variables measured including axial length, corneal mean curvature, bag or sulcus implantation, formula used, or age at primary and secondary surgery (p > 0.05).

CONCLUSIONS

The mean absolute value of prediction error observed in this study is consistent with previous pediatric primary and secondary IOL data in that it shows a considerable difference from that expected in adult populations. Our findings support the argument that methods currently employed to calculate IOL power may fail to accurately account for all the variations in the eyes of pediatric patients.

Accuracy of biometry in pediatric cataract extraction with primary intraocular lens implantation

PURPOSE

To determine the accuracy of predicted postoperative refractive outcomes in pediatric patients having cataract surgery with intraocular lens (IOL) implantation and to compare them with other variables historically considered important in cataract surgery.

SETTING

Tertiary care referral hospital.

METHODS

This retrospective review comprised 203 eyes of 153 consecutive pediatric patients (< or = 18 years old) having cataract extraction with primary posterior chamber IOL implantation in the capsular bag. All cases were performed by 1 of 2 surgeons, and all refractions were performed manually by an experienced pediatric ophthalmologist using a retinoscope.

RESULTS

In all patients, the mean absolute value (MAE) of the prediction error was 1.08 diopters (D) +/- 0.93 (SD). Age at time of surgery and corneal (K) mean curvature were significantly correlated with the absolute value of the prediction error (P = .0006 and P = .0088, respectively). A multiple regression model showed that age at time of surgery and K mean curvature were the only 2 variables significantly associated with MAE; axial length, formula, surgeon, and A-scan type were not significantly associated with prediction error.

CONCLUSIONS

Data from 203 consecutive primary pediatric IOL implantations showed the heterogeneous nature of the variables involved in predictions of refractive outcomes in this population. The complexities of this issue support the need for specific methods of measurement and an IOL calculation formula for the pediatric population.

Pulsatile ocular blood flow: relationship with flow velocities in vessels supplying the retina and choroid

BACKGROUND

Although ocular tonography measures a pulsatile component of the ocular perfusion, the retinal and/or choroidal components of this pulsatile flow remain undefined.

AIM

To compare ocular tonography with the assessment of flow velocities in arteries supplying the retina, choroid and entire orbit.

METHODS

22 normal eyes from 11 subjects were studied. Pulsatile ocular blood flow (POBF) was measured using the ocular blood flow tonograph, and flow velocities in the ophthalmic, central retinal (CRA) and temporal short posterior ciliary arteries (TSPCA) using colour Doppler imaging. The correlation between POBF and retrobulbar flow velocities was determined.

RESULTS

POBF correlated significantly with peak systolic velocity (PSV) of the CRA (r = 0.56, p = 0.007) and the TSPCA (r = 0.48, p = 0.02), and with the resistive index of the TSPCA (r = 0.45, p = 0.04). Additionally, pulse amplitude (PSV-end diastolic velocity) in the CRA and the TSPCA correlated significantly with POBF measurements (each p<0.05). However, POBF did not correlate with any flow velocity indices in the ophthalmic artery.

CONCLUSION

POBF is associated with systolic and pulsatile components of blood flow velocities in both the CRA and the TSPCA. This result suggests that POBF determinations are influenced by the pulsatile components of both choroidal and retinal perfusion.