Choroidal thickness profile in retinitis pigmentosa - correlation with outer retinal structures

Purpose: To compare the choroidal thickness [CT] of subjects with Retinitis Pigmentosa [RP] with age-matched healthy subjects and to correlate the visual acuity with retinal parameters including central macular thickness [CMT], inner segment/outer segment junction [IS/OS junction] integrity, external limiting membrane [ELM] integrity and choroidal thickness in subjects with RP

Methods: Eighty-eight eyes [69 patients] with typical RP and 188 eyes of 104 healthy subjects were enrolled between September 2012 and January 2013. All subjects underwent a comprehensive ocular examination including choroidal imaging using enhanced depth imaging with spectral domain optical coherence tomography. Outcome measures were CT difference between RP and age-matched healthy subjects; and correlation of various factors such CMT, IS/OS junction integrity, ELM integrity, and CT with visual acuity

Results: Among RP subjects, mean age was 31.39 +/- 13.4 years with a mean BCVA of 0.99 +/- 0.94 logMAR. Mean spherical equivalent was -0.6 +/- 1.6D. Mean CMT was 148.48 +/- 119 micro m. Mean subfoveal CT was 296.9 +/- 72 micro m. Mean IS/OS and ELM integrity was 42.2 +/- 46.6% and 43.75 +/- 45.7%, respectively. The mean age was 40.0 +/- 13.5 years with a mean spherical equivalent of 0.18 +/- 0.6D for the normal age-matched healthy group. Mean subfoveal CT was 283.1 +/- 47.8 micro m. CT at various locations in patients of various ages in the RP group did not show any statistical significant difference [P = >>0.05] in comparison with age-matched healthy subjects. On multivariate regression, ELM percentage integrity had the strongest association with best corrected visual acuity, followed by IS/OS junction percentage integrity. Subfoveal choroidal thickness had very weak correlation with visual acuity as well other retinal parameters. There was a significant difference in the outer retinal structure integrity [p = 0.002] and CMT [p = 0.02] between the eyes with good [>/=20/200] and poor vision [<20/200], but not in subfoveal choroidal thickness [p = 0.3]

Conclusions: Our study results did not show any significant difference in choroidal thickness between subjects with RP and agematched healthy subjects. Choroidal thickness correlated better with the age but not with the vision or outer retinal structures in eyes with RP. Outer retinal structure integrity and CMT had a better correlation with visual acuity

Systemic steroids as an aid to the management of Idiopathic polypoidal choroidal vasculopathy [IPCV]: a descriptive analysis

Purpose: To determine the role of systemic steroids in improving visual acuity, preventing recurrence and hastening pigment epithelial detachment resolution in IPCV patients

Methods: Retrospective computer assisted comparative case series of consecutive patients with documented IPCV who did and did not receive systemic steroids as part of their treatment regimen between 2007 and 2012. Patients who had systemic contraindication to steroid therapy were excluded from the steroid arm. Data collected included demographics, the best corrected visual acuity, details of the ocular and systemic exam, the treatment offered, the follow-up period and the final visual and anatomic outcomes. Outcome measures included the final BCVA, the time to resolution of the associated pigment epithelial detachment [PED, if present], the recurrence rate and the associated side effects, if any. Appropriate statistical analysis was done. Statistical significance: p < 0.05

Results: 14 patients [14 eyes] had received systemic steroids in the stated period; these were compared with 26 consecutive patients [26 eyes] who did not. Meanage: 59.24 vs 62.38 years [A vs B]. Mean baseline BCVA: 1.86 +/- 1.24 logMAR vs 2.12 +/- 1.48 logMAR [A vs B]. 8 females in Group A and 14 in Group B. 11 patients in group A and 19 in group B had associated systemic hypertension. Therapy consisted of laser photocoagulation, anti-vascular endothelial growth factor therapy, photodynamic therapy or a combination of these. Mean follow-up: 43.21 +/- 11.32 months [Group A] vs 48.24 +/- 9.75 months [Group B]. BCVA at three months was significantly better [0.84 +/- 0.74 logMAR vs 1.16 +/- 0.89 [p = 0.039]. Final BCVA: 0.86 +/- 0.78 logMAR [Group A] vs 1.29 +/- 0.92 [Group B, p = 0.042]. 7 patients in group A and 12 in Group B had a recurrence [insignificant difference]. 1 patient in Group A and 7 in Group B had unresolved disease [persistent PED] at the end of follow-up [OR: 4.60; 95% CI 1.7-11.10]

Conclusion: Steroids appear to improve visual acuity and accelerate the resolution of the PEDs in patients with IPCV and large PEDs, but do not seem to influence recurrence

Echographic study of extraocular muscle thickness in normal Indian population

To establish normative data of extraocular muscle [EOM] dimensions, both vertically and horizontally, using a reproducible echographic method in various age groups. Two hundred eyes of 100 healthy subjects [50 males and rest females] were included in this prospective observational study. All subjects were divided into 5 groups with an interval of 10 years from 10 to 60 years. Each group contained 10 male and 10 female healthy subjects. A single operator took measurements at 4 mm distance from the globe plane after drawing a perpendicular line on the globe to the muscle belly. The average age of subjects was 37.28 +/- 17.14 years. Intraobserver reproducibility was very high [intersession concordance correlation co-efficient = 0.995]. Mean horizontal and vertical diameters of recti were 3.0775 and 8.26 mm, respectively. Mean muscle thickness of superior rectus/levator palpebral superioris [IPS] muscle complex and IPS was 4.56 and 1.45mm, respectively. Extraocular muscle diameter increases up to the middle age, then it starts decreasing. There was no statistically significant correlation between diameter of each EOM, both eye and gender [p >/= 0.05]. There was a non-significant change in extra-ocular muscle thickness with age. The study provides normative data for extraocular muscle thickness in both genders of various age groups in Indian population. Muscle dimensions do not change significantly with age, between the eyes and gender