Intraocular Pressure in the Eyes of Patients With Carotid-Cavernous Fistulas: Profile, Intereye Asymmetry, and Treatment Outcomes.

PRECIS: Secondary ocular hypertension (OHT) is common in carotid-cavernous fistulas (CCFs). Management of elevated intraocular pressure (IOP) is possible with a multidisciplinary approach. The ipsilateral normal eyes may have higher IOP than the contralateral eyes. PURPOSE: To study the IOP profile of the eyes of patients with a CCF, treatment outcomes for elevated IOP, and intereye IOP asymmetry in the eyes with normal IOP. METHODS: This was a retrospective case series. A total of 64 eyes of 60 patients with digital subtraction angiography-proven CCF diagnosed from the year 2000 to 2016 were included. The demographics, clinical features, management, and outcomes were recorded. The primary outcome included understanding of the cause of elevated IOP. The secondary outcomes included comparison of the IOP between contralateral eyes and ipsilateral normal eyes (IOP <21 mm Hg) and management outcomes for elevated IOP. RESULTS: The mean age of the patients was 45.6±18.2 years. In the study population, 70% of the patients were males. Indirect CCF was present in 55% of the eyes. It was found that 64.06% (n=41) of the eyes had elevated IOP, glaucoma, or were glaucoma suspects. Among all the eyes, 40.62% (n=26) of the eyes had secondary OHT due to elevated episcleral venous pressure, whereas 7.81% (n=5) of the eyes had secondary open-angle glaucoma. The mean IOP was higher in the ipsilateral eyes than in the other eyes (22.95±7.1vs. 15.11±2.99 mm Hg; P<0.001). The mean IOP in the ipsilateral normal eyes was higher than that in the contralateral eyes, with a mean difference of 2.92±2.29 mm Hg (confidence interval of the mean difference: 1.90-3.94 mm Hg; P<0.0001). IOP reduction (<21 mm Hg) was achieved in 70.7% of the patients following CCF management with intermittent carotid massage, endovascular treatment, IOP-lowering medications, or a combination among these. CONCLUSIONS: Secondary OHT due to elevated episcleral venous pressure was more common than secondary open-angle glaucoma. Ipsilateral normal eyes had higher IOP than contralateral eyes. IOP-lowering agents and management of CCF resulted in IOP control in most patients.

Optic disc dimensions and cup-disc ratios among healthy South Indians: The Chennai Glaucoma Study.

PURPOSE: To present optic disc and cup dimensions, cup-disc ratios (CDRs) and asymmetry among healthy South Indians, and their associations with ocular and systemic variables. METHODS: A total of 623 healthy phakic participants of the Chennai Glaucoma Study underwent complete eye examinations including optic disc stereo-photography. Planimetry was performed under stereo-viewing conditions. The morphological type of cupping (no cups, steep cups, partly sloping and fully sloping cups) was identified based on a modification of the classification by Jonas et al.( 11 ) The associations of planimetric measures (optic disc area, cup area and vertical cup-disc ratio [VCDR]) with age, gender, height, intraocular pressure, refraction, astigmatism, axial length and corneal thickness as explanatory variables were examined. The associations of asymmetries in the above planimetric measures with age, gender and asymmetries of the above explanatory variables were examined. RESULTS: Mean optic disc and cup areas were 2.82 ± 0.52 mm(2) and 0.53 ± 0.39 mm(2). Mean CDR was 0.36 ± 0.18. Men had larger discs (P = 0.03). Cup area and VCDR revealed significant associations with disc area (P <0.0001) and type of cupping (P < 0.0001). Mean disc and cup area asymmetries were 0.19 ± 0.16 mm(2) and 0.15 ± 0.15 mm(2). Mean VCDR asymmetry was 0.07 ± 0.08 mm(2). Cup area and VCDR asymmetries showed significant associations with disc area asymmetry (P < 0.0001, both) and asymmetry in the presence or absence of physiological cupping, i.e. subjects with physiological cupping in one eye and no cupping in the other (P < 0.0001, both). CONCLUSIONS: We present normative optic disc, cup and VCDR measures and asymmetries among healthy South Indians. We demonstrated the dependence of VCDR on the morphological type of cupping.

Neural rim characteristics of healthy South Indians: the Chennai Glaucoma Study.

PURPOSE: To report neural rim dimensions for South Indians and examine rim shape with relevance to clinical evaluation. METHODS: Healthy phakic participants (n = 623) of the Chennai Glaucoma Study with normal frequency-doubling perimetry underwent complete eye examinations including optic disc digital stereophotography. Planimetry was performed under stereoviewing conditions using custom software. Rim area, shape, and associations were examined. Rim area asymmetry was studied in a subgroup of 565 subjects. RESULTS: Mean neuroretinal rim area was 2.29 +/- 0.39 mm(2). Disc area (P < 0.001) and type of cupping (P < 0.001) were associated with rim area. Mean rim area asymmetry was 0.18 +/- 0.15 mm(2); 95% of subjects had asymmetry < 0.5 mm(2). Disc area asymmetry (0.359, P < 0.0001) and intraocular pressure (IOP) asymmetry (P = 0.004) were related to rim area asymmetry. On average, the inferior rim was thickest and the temporal was thinnest. Mean inferior by superior rim width was 1.18 +/- 0.17; 2.5 percentile, 0.9. Thirty-eight (7.1%) subjects had the superior rim thicker than the inferior rim, the occurrence of which was associated with disc torsion (P = 0.002) and male sex (P = 0.04). Of the clinically relevant rim width measures in glaucoma (i.e., inferior, superior, and temporal) the temporal rim was thinnest in 469 (87.8%) eyes. Horizontally oval disc shape (P < 0.0001), type of cupping (P = 0.006), and astigmatism (P = 0.001) were associated with the presence of thicker temporal than superior/inferior rims. CONCLUSIONS: The report provides hitherto unreported neural rim measurements among healthy South Indians. The ISNT rule (inferior rim thicker than superior rim, thicker than nasal rim, thicker than temporal rim) was violated in a significant minority. Physiological associations with such violations are described.

Intraocular pressure changes and ocular biometry during Sirsasana (headstand posture) in yoga practitioners.

PURPOSE: To study the intraocular pressure (IOP) changes in Sirsasana (headstand posture) done by experienced yoga practitioners and correlate the ocular biometric parameters with the IOP changes, and to screen for the prevalence of ocular hypertension in this group of subjects. DESIGN: Prospective case observational series. PARTICIPANTS: Seventy-five subjects (50 Asian Indians and 25 Caucasians) from a yoga training institute volunteered for the study. METHODS: All participants underwent a detailed ophthalmic examination along with ocular biometry and corneal pachymetry. Intraocular pressure was recorded using a Tonopen before, during, and after the Sirsasana. Changes were compared using the paired t test. Age, axial length, anterior chamber depth, lens thickness, corneal curvature, corneal thickness, race, and the length of time for which the practitioner was performing yoga were correlated with the induced IOP difference in a randomly selected eye using Pearson's correlation coefficient with Bonferroni correction for multiple comparisons. MAIN OUTCOME MEASURES: Ocular biometry and induced IOP difference. RESULTS: The mean increase in IOP at baseline and immediately after assuming Sirsasana was 15.1+/-4.1 mmHg (R = 0.07; P = 0.999) and after 5 minutes was 15.8+/-4.6 mmHg (R = -0.25; P = 0.357). The induced increase in IOP during the posture was twice the baseline IOP. There was no correlation between age, ocular biometry, and ultrasound pachymetry when compared with the induced IOP difference. One subject (1.33%) was found to have baseline IOP of more than 21 mmHg. CONCLUSION: There was a uniform 2-fold increase in the IOP during Sirsasana, which was maintained during the posture in all age groups irrespective of the ocular biometry and ultrasound pachymetry. We did not demonstrate a higher prevalence of ocular hypertensives in this cohort of yoga practitioners nor did the risk factors contributing to glaucoma show any correlation with magnitude of IOP raise during the posture.