PURPOSE: (i) To investigate whether pulsatility index (PI) and mean flow velocities (MFV) are altered in glaucoma patients. (ii) To evaluate the significance of PI in retrobulbar autoregulation capacity. METHODS: Patients with primary open-angle glaucoma (POAG; n = 49), normal tension glaucoma (NTG; n = 62) and healthy controls (n = 48) underwent colour Doppler imaging measurements of the retrobulbar vasculature. Kruskal-Wallis test was used to compare variables between the three diagnostic groups. Restricted cubic splines were used to determine nonlinearities between the resistive index (RI) and PI correlations. RESULTS: Mean flow velocities (MFV) were lower in both short posterior ciliary arteries (SCPA) and central retinal arteries (CRA) from the two glaucoma groups (p < 0.04 versus healthy controls). No differences were detected in RI or PI in any arteries of the three diagnostic groups (p > 0.08). In healthy individuals, correlations between RI and PI were linear in all arteries. In both POAG and NTG patients, CRA presented a nonlinear curve with a cutpoint at RI 0.77 (p < 0.001) and 0.61 (p = 0.03), respectively, above which the slope increased nearly five- and tenfold (POAG: 1.96 to 10.06; NTG: -0.46-4.06), respectively. A nonlinear correlation in the ophthalmic artery was only observed in NTG patients, with a cutpoint at RI 0.82 (p < 0.001), above which the slope increased from 3.47 to 14.03. CONCLUSIONS: Glaucoma patients do not present the linear relationships between RI and PI observed in healthy individuals. Their nonlinear relations may be indicative of an altered autoregulation and suggest a possible threshold RI could be determined above which autoregulatory disturbances become more relevant.

PURPOSE: Recently, the absence of spontaneous venous pulsation (SVP) has been suggested as a vascular risk factor for primary open-angle glaucoma (POAG). As the mechanism behind this phenomenon is still unknown, the authors have studied this vascular component using colour Doppler imaging (CDI). METHODS: A total of 236 patients were divided into three diagnostic groups: healthy controls (81), POAG (86) and normal tension glaucoma (NTG; 69). All subjects were submitted to CDI studies of the retrobulbar circulation, intraocular pressure measurements and assessment of SVP existence. Mann-Whitney, chi-square contingency tables and Spearman correlations were used to explore differences and correlations between variables in the diagnostic groups. RESULTS: Eighty-two percent of healthy controls had SVP (66/81), while a smaller numbers were registered in both glaucoma groups: POAG - 50% (43/86); NTG - 51% (35/69). In NTG patients, but not in POAG patients, the prevalence of the SVP phenomenon decreases with increased glaucoma damage (p = 0.04; p = 0.55, respectively). Overall glaucoma patients from both groups had lower central retinal vein (CRV) velocities than the healthy controls (p < 0.05). NTG patients with SVP had less severe visual field defects (mean defect -6.92 versus -11.1, p < 0.05), higher [correction added after online publication 21 September 2012; the word 'higher' has been inserted to replace the word 'lower'] peak systolic and mean flow velocities in the central retinal artery (p < 0.01; p < 0.05, respectively) as well as higher [correction added after online publication 21 September 2012; the word higher has been inserted to replace the word lower] maximal velocities and RI of the CRV (p < 0.02; p < 0.05, respectively). CONCLUSIONS: Glaucoma patients have a decrease in CRV velocities. SVP is less prevalent in glaucoma patients than in healthy individuals. This phenomenon apparently reflects different hemodynamic patterns in the central retinal vessels. This variable may be of particular importance in NTG patients, where it may be associated with more advanced functional damage.

PURPOSE: To report the visual outcomes and complications of congenital cataract surgery with primary intraocular lens implantation in microphthalmic eyes of children younger than 4 years of age. METHODS:This retrospective interventional case series included 14 microphthalmic eyes from 10 children who underwent congenital cataract surgery with primary intraocular lens implantation younger than 4 years of age. Seven patients had bilateral cataracts (11 eyes met the study's inclusion criteria) and 3 patients had unilateral cataract. Patients' medical charts were reviewed to obtain information regarding the preoperative and postoperative ophthalmological examination. Main outcome measures were intraocular pressure (IOP), best-corrected visual acuity, and intraoperative and postoperative complications. RESULTS: Mean age at the time of surgery was 21.7 ± 2.9 months. Mean ocular axial length was 19.2 ± 0.9 mm. Mean preoperative IOP was 9.7 ± 1.7 mmHg and 10.3 ± 3.1 mmHg on final follow-up (P=0.18). There were no intraoperative complications. Two (15.4%) eyes developed secondary visual axis opacification, of which only one needed to be reoperated due to significantly decreased vision (0.5 logMAR). Preoperative and postoperative best-corrected visual acuity was 2.09 ± 0.97 logMAR and 0.38 ± 0.08 logMAR in bilateral cases and 1.83 ± 1.04 logMAR and 0.42 ± 0.13 logMAR in unilateral cases, respectively. CONCLUSION: Primary intraocular lens implantation in congenital cataract surgery in microphthalmic eyes resulted in a significant best-corrected visual acuity improvement with no intraoperative complications and minimal postoperative complications.