Study of the Correlation Between Severity of Endophthalmitis and Posterior Vitreous Detachment Using a Rabbit Endophthalmitis Model.

Purpose: We have reported that the absence of posterior vitreous detachment (PVD) is related to the onset and severity of infectious endophthalmitis, based on clinical experience. To demonstrate clinical findings in animal models, we created endophthalmitis models for the presence or absence of PVD and examined differences in severity. Method: We estimated a rabbit infectious eye model with and without PVD using Pseudomonas aeruginosa (PVD(+) and PVD(-) groups). After injection of bacteria inoculation for 3, 6, 12, and 24 hours, we evaluated the clinical score of the anterior chamber (n = 14). Removing the vitreous and retina from the enucleated eyeballs, the number of bacteria was counted using each specimen (n = 12). In addition, the number of inflammatory cells approximately 3 mm2 around the optic disc and histopathologic grading of intraocular inflammation was compared from histopathologic images (n = 7). Electroretinogram (ERG) was performed in experimentally infected rabbit eyes in both groups at three times after injection of the bacterial suspension. Results: There was no difference between the two groups in the clinical score of the anterior chamber of each time phase, but the bacterial cultures showed significantly fewer bacteria in the PVD(-) group 24 hours after bacterial inoculation (P < 0.05). Furthermore, the number of inflammatory cells was significantly less in the PVD group (P < 0.05). As a result of ERG, the decreases of a- and b-waves in amplitude were significantly greater in the PVD(-) group than in the PVD(+) group. Conclusions: The present study confirms using animal models that the absence of PVD contributed to the severity of bacterial endophthalmitis.

EFFICACY OF THE INVERTED INTERNAL LIMITING MEMBRANE FLAP TECHNIQUE WITH VITRECTOMY FOR RETINAL DETACHMENT ASSOCIATED WITH MYOPIC MACULAR HOLES.

PURPOSE: To evaluate the anatomical and functional outcome of the inverted internal limiting membrane (ILM) flap technique with vitrectomy for retinal detachment associated with macular hole (MHRD) in highly myopic eyes. METHODS: In this retrospective observational study, 21 eyes with MHRD that underwent vitrectomy with conventional ILM peeling (ILM-peeling group, n = 11) or the inverted ILM flap technique (ILM flap group, n = 10) combined with C3F8 tamponade were enrolled in this study. The initial retinal reattachment rate, macular hole closure rate, and postoperative visual acuity at the final visit were compared between the ILM-peeling group and ILM flap group. RESULTS: There was no significant difference in the retinal reattachment rate between ILM-peeling and ILM flap groups (91% and 100%, respectively). The macular hole closure rate in the ILM flap group was 80% (8 of 10 eyes), and was significantly higher than 36% (4 of 11 eyes) in the ILM-peeling group (P = 0.039). Among 12 eyes that achieved macular hole closure, there was no significant difference in median visual acuity after vitrectomy between the ILM flap group and ILM-peeling group (logMAR unit [Snellen acuity]: 1.0 [20/200] and 0.76 [20/125], respectively, P = 0.300). CONCLUSION: Compared with conventional ILM peeling, the inverted ILM flap technique was more effective for macular hole closure after vitrectomy for MHRD in myopic eye but showed no advantage in the postoperative visual outcome in this study.

Gd3TCAS2: An Aquated Gd(3+)-Thiacalix[4]arene Sandwich Cluster with Extremely Slow Ligand Substitution Kinetics.

In aqueous solution, Gd(3+) and thiacalix[4]arene-p-tetrasulfonate (TCAS) form the complex [Gd3TCAS2](7-), in which a trinuclear Gd(3+) core is sandwiched by two TCAS ligands. Acid-catalyzed dissociation reactions, as well as transmetalation and ligand exchange with physiological concentrations of Zn(2+) and phosphate, showed [Gd3TCAS2](7-) to be extremely inert compared to other Gd complexes. Luminescence lifetime measurements of the Tb analogue Tb3TCAS2 allowed estimation of the mean hydration number q to be 2.4 per Tb ion. The longitudinal relaxivity of [Gd3TCAS2](7-) (per Gd(3+)) was r1 = 5.83 mM(-1) s(-1) at 20 Hz (37 °C, pH 7.4); however, this relaxivity was limited by an extremely slow water exchange rate that was 5 orders of magnitude slower than the Gd(3+) aqua ion. Binding to serum albumin resulted in no relaxivity increase owing to the extremely slow water exchange kinetics. The slow dissociation and water exchange kinetics of [Gd3TCAS2](7-) can be attributed to the very rigid coordination geometry.