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PURPOSE: A prospective study was performed to evaluate refractive and ocular biometric changes in acute hyperglycemic status in patients with diabetes mellitus. METHODS: From January to August 2002, 48 eyes of 24 patients with persistent diabetes and a plasma glucose level>or=17 mmol/L or HbA1c>or=10.0% on admission were enrolled in this prospective study. Upon admission to Tri-Service General Hospital in Taipei, Taiwan, these patients underwent intensive glycemic control. The basic ophthalmic examinations, including visual acuity, intraocular pressure measurement, slit lamp, and fundus examinations, were conducted. The ocular parameters including refraction, anterior chamber depth, lens thickness, axial length, mean keratometry, and thinnest corneal thickness were evaluated by A-mode scan and Orbscan II. Each patient underwent clinical follow-up visits at 1, 2, and 4 weeks after the acute hyperglycemic episode. RESULTS: Of the 24 patients, 18 were male and 6 were female. The mean age of the patients was 55 years (range: 38 to 69). Comparing the refractive status on admission and at week 4, the authors found that 8 cases (16 eyes, 33%) showed hyperopia during hyperglycemia (+1.9+/-0.8 D), but in the other 16 cases (32 eyes, 67%), there were no significant changes. In addition, there were also no significant changes in anterior chamber depth, lens thickness, axial length, thinnest corneal thickness, or mean keratometry in the follow-up period. CONCLUSIONS: Transitory hyperglycemia produces hyperopia. The alteration in refractive index in the lens may contribute to the hyperopic change, but no change of ocular biometrics in lens or cornea is observed.

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An 83-year-old man who had phacoemulsification and ciliary sulcus fixation of a posterior chamber intraocular lens developed capsular block syndrome with secondary glaucoma 1 year after surgery. The glaucoma resolved, and vision returned immediately after a neodymium:YAG laser capsulotomy was performed. Capsular block syndrome with secondary angle-closure glaucoma should be considered in pseudophakic patients presenting with increased intraocular pressure and a narrow angle.

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Alstrom syndrome is a very rare autosomal recessive inherited disorder. Only 50 cases have been reported since the syndrome was first described in 1959. This syndrome is characterized by obesity, impaired glucose tolerance with insulin resistance, retinal degeneration, neurosensory deafness, acanthosis nigricans, hepatic dysfunction, and some endocrine disorders. The index case of this report was a 12-year-old girl who became blind at the age of 6 years as the result of progressively impaired vision. At the age of 12, diabetes mellitus was diagnosed and acanthosis nigricans presented in the neck, axilla, and groin regions. Her 10-year-old brother had similar symptoms. Electroretinography and audiometry disclosed generalized pigmentary epithelial change, decreased to absent cone and rod responses, and moderate sensorineural hearing loss in both siblings. Biochemistry and oral glucose tolerance tests showed diabetes mellitus, dyslipidemia, and hepatic dysfunction in the index case. Elevations of insulin, C-peptide, and leptin concentrations were found in both siblings. Insulin resistance was also demonstrated in both siblings using the modified insulin suppression test with constant infusion of somatostatin and exogenous insulin.

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Antimetabolite therapy with 5-fluouracil (5-FU) or mitomycin-C (MMC) has significantly improved the success rate of glaucoma filtration surgery. However, in some eyes, when filtration is excessive, persistent hypotony may develop. In this study, we describe the experience of using autologous fibrinogen concentrate (AFC) to treat patients with persistent hypotony after glaucoma filtration surgery. Among seven MMC-augmented trabeculectomy patients who developed persistent postoperative hypotony, the effects of AFC intrableb injections were evaluated. Under a microscope, 0.2 ml AFC and bovine thrombin were injected into the blebs of the patients from both sides of the filtering blebs. Postoperative best-corrected visual acuity, anterior chamber status, intraocular pressure (IOP) and fundus examination were followed and compared with those preoperative. On the second day, the mean IOP of seven eyes elevated from preoperative 3.4 +/- 2.1 mmHg to 12.6 +/- 4.2 mmHg, and the anterior chamber became deep without obvious inflammatory response. Within two weeks, macular edema and visual acuity were noted to improve in six eyes (85.7%). In addition, after a mean follow-up of 25 months, the trabeculectomy procedure remained successful in all eyes. AFC appears to be safe and effective in the treatment of ocular hypotony after glaucoma filtration surgery.

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PURPOSE: To demonstrate the phenomenon of adrenergic denervation supersensitivity in rabbit choroidal blood vessels after superior cervical ganglionectomy. METHODS: Twenty four albino rabbits of both sexes weighing 2-3 kg were randomly separated into two groups. Twelve rabbits received bilateral superior cervical sympathectomy 2 weeks prior to the study (group s). The other 12 rabbits served as controls (group n). Four different concentrations of 0.1 ml phenylephrine, 0.05%, 0.025%, 0.013%, and 0.007% were slowly injected into the vitreous body near the retinal surface in group (n) and (s) rabbits (n = 6 in each group). The choroidal blood flow (PF), blood volume (CMBC), and velocity (V) were measured simultaneously by laser Doppler flowmetry (Perimed, PF 4001). RESULTS: The PF showed similar decreases in group (n) and (s) rabbits after injection of 0.05%, 0.025%, and 0.013% phenylephrine. With 0.007% phenylephrine, the PF remained unchanged in group (n) rabbits, but decreased significantly in group (s) rabbits (p = 0.0007). Velocity decreased similarly in both group (n) and (s) rabbits except for the 0.007% phenylephrine, concentration in which velocity decreased significantly in group s rabbits (p = 0.0001). There was no statistical difference in CMBC between group n and s rabbits at any of the test concentrations. CONCLUSIONS: The difference in PF decrease between group (n) and (s) rabbits with 0.007% phenylephrine demonstrated the existence of choroidal blood vessel denervation supersensitivity. The decrease in PF was achieved mainly through a decrease in blood cell velocity.

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This study evaluates the effect of different doses ofpentoxifylline on rabbit choroidal blood flow (CBF). Sixteen albino rabbits of both sexes, weighing 2.0-3.0 kg, were randomly separated into four groups. The first group of rabbits received 2 ml normal saline injection through the ear vein. They served as the control group (group n). Three different doses of pentoxifylline, 1 mg/kg, 5 mg/kg, and 10 mg/kg, were injected intravenously to groups p1, p5 and p10, respectively. By means of a laser Doppler flowmeter, the blood cell flux (PF), velocity, and the concentration of moving blood cells (CMBC) were recorded simultaneously. The laser probe was advanced through the pars plana and positioned near the retinal surface. The mean arterial pressure was recorded at the same time. There was a significant increase in PF at 1, 5 and 10 min in group p10 rabbits compared with the control group (p=0.0005, 0.0416, and 0.0087, respectively). The velocity increased at 5 min in group p5 rabbits (p=0.0082) and at 1, 5 and 10 min in group p10 rabbits (p=0.0188, 0.0080, and 0.0207, respectively) as compared with the controls. The CMBC decreased after injection of pentoxifylline and reached statistical significance at 5 and 10 min in group p5 rabbits (p=0.0019 and 0.0046, respectively) and at 5 min in group p10 rabbits (p=0.0447). These results show that larger doses of pentoxifylline (10 mg/kg) increased the CBF of rabbits. This effect was achieved primarily by an increase in blood cell velocity.

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PURPOSE: To report a case of caterpillar setae embedded in the deep cornea and anterior chamber. METHODS: A 26-year-old man was struck in his right eye by a caterpillar (Dendrolimus punctatus walker). Severe conjunctival injection, chemosis, and erosion of the cornea developed immediately. Numerous setae fragments were found to be embedded into the palpebral conjunctiva and deep cornea, extending into the anterior chamber near the anterior iris surface. RESULTS: After partial removal of the setae under a microscope, the inflammation subsided and visual acuity improved to RE: 20/20. CONCLUSION: Caterpillar setae are sharp enough to penetrate the cornea and extend into the anterior chamber.

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The water drinking test (WDT) was once frequently used as a diagnostic tool for glaucoma, but not so often nowadays. In this study, we investigated the potential use of the WDT on the evaluation of trabeculectomy patency. Twenty age-matched volunteers and thirty-six glaucoma patients who were to receive trabeculectomy procedure were enrolled in this study. The WDT was given to the volunteers once and to all glaucoma patients before undergoing trabeculectomy and at certain intervals after the procedure. The WDT was performed in a standard manner. We defined four parameters after performing the WDT: Initial Pressure [IP, intraocular pressure (IOP) level before the WDT]; Slope of Ascending Trend (SOAT, the slope between baseline IOP and the highest IOP level); Peak Pressure (PP, the highest IOP level during the WDT); and End Pressure (EP, the IOP level after the WDT). It was found that the results of the WDT and trabeculectomy patency were strongly correlated. The four parameters in success and failure cases were significantly different at the last follow up: IP: (15.2 +/- 3.6 vs. 25.3 +/- 6.4, p<0.01); SOAT: (0.9 +/- 0.3 vs. 1.8 +/- 1.2, p<0.01); PP: (19.2 +/- 6.4 vs. 39.5 +/- 12.2, p<0.01); EP: (15.5 +/- 4.8 vs. 29.4 +/- 8.2, p<0.01). Thus, it was observed in this study that WDT was not only easy and safe to perform, but also valuable in evaluating the patency of trabeculectomy.

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A prospective, randomized study was performed to examine the effects of subconjunctival retention of 5-fluorouracil (5-FU) microparticles or 5-FU microparticles combined with mitomycin-C (MMC) on the success of trabeculectomy procedure in 32 New Zealand white rabbits. Drug-loaded microparticles were prepared using a biodegradable polymer, 50:50 ploy (D,L-lactide-co-glycolide) (50:50, PLG, MW 9000), by an oil-in-oil emulsification/solvent extraction technique. Each rabbit underwent trabeculectomy on both eyes, then one of the 5-FU and/or MMC preparations was placed at the site of the filtering surgery intraoperatively in the right eye, while the left eye was used as a control. The rabbits were randomly allocated to one of four treatment groups: group 1 rabbits received 5% 5-FU microparticles 10 mg; group 2 rabbits received 10% 5-FU microparticles 10 mg; group 3 rabbits received 10% 5-FU microparticles 5 mg and MMC 0.01 mg (5-FU/MMC); and group 4 rabbits received MMC 0.02 mg. Postoperatively, intraocularpressure (IOP), bleb survival, complications and IOP dynamics were compared during a follow-up period of 42 days. The results showed that IOPs were significantly lower in the eyes that received groups 3 and 4 treatments, while the eyes that received low concentrations of 5-FU microparticles resulted in no difference in IOPs as compared with those of controls. At 42 days, blebs were present in 100% of the eyes treated with 5-FU/MMC and MMC, but 0% of the eyes treated with 5-FU microparticles. The blebs in the eyes treated with MMC 0.02 mg were thinner, and significant complications (endophthalmitis, transient corneal opacification and neovascularization) occurred. In addition, the IOP dynamics study revealed that the eyes treated with 5-FU/MMC and MMC resulted in less IOP spikings after intravenous infusion of 0.9% NaCl solution. Our study suggested that the use of 5-FU microparticles in promoting the success of trabeculectomy in rabbits is dose-dependent, and its effect is less potent than a single intraoperative application of MMC.

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In this study, we investigate the innervation to the feline ophthalmic artery by the horseradish peroxidase (HRP) tracing method. Five adult cats with body weights ranging between 2.0 and 3.0 kg were used. Under microscopic dissection, the ophthalmic artery was identified and isolated. A gelfoam (Upjohn Co.), 1 x 3 mm in size, containing 0.1 ml of HRP was applied to the prepared artery segment for 2 h. The cat was sacrificed 3 days later. The trigeminal, stellate, superior cervical, middle cervical and nodal ganglia, and oculomotor, trochlear and abducens nuclei were removed, sectioned and stained for HRP-positive cells. HRP-labeled neurons were found in the ipsilateral trigeminal (TRG) and superior cervical ganglia (SCG). The middle cervical, stellate, Edinger-Westphal, trochlear and abducens nuclei were all deemed negative for HRP-labeled cells. In the TRG, HRP-labeled neurons ranged from 21 to 250 (mean +/- SE = 93.8 +/- 42.5/ganglion). The labeled neurons were distributed primarily in the ophthalmic branch. In the SCG, the HRP-labeled neurons were distributed evenly in the ganglion, ranging from 6 to 180 (mean +/- SE = 91.6 +/- 31.5/ganglion). Two additional cats having received a sham operation revealed a negative finding. The feline ophthalmic artery is innervated by the ipsilateral TRG and SCG. Such innervation may play a role in regulating blood flow to the optic nerve.

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The effect of subconjunctival retention of perfluoropropane (C3F8) gas on rabbit trabeculectomy was evaluated in this study to determine if this maneuver would increase the success rate of the surgery. Sixteen New Zealand white rabbits underwent trabeculectomy in the right eyes and trabeculectomy with subconjunctival retention of 0.3 mL C3F8 gas in the left eyes were used as animal models. One week and six weeks after the operations, the intraocular pressure (IOP) dynamics were compared between the two eyes after intravenous infusion of 0.9% NaCl sterile solution. The results showed that the average retention time of C3F8 gas within the subconjunctival space in the rabbits was 9.5 +/- 2.3 days. There were four parameters available in comparing IOP dynamics: Time Needed to Reach Peak IOP (TNRPI); Ascending Slope (AS); Peak IOP (PI) and Time Needed to Return to the Original IOP (TNROI). It was noted that at the 7th day after the operations, the IOPs in both eyes of the rabbits were not significantly increased after intravenous infusion of 0.9% NaCl solution. At the 42nd day, after 0.9% NaCl intravenous infusion, the eyes that had undergone trabeculectomy and subconjunctival retention of C3F8 gas had less IOP spiking than eyes that had undergone trabeculectomy alone (TNRPI: 6.7 +/- 2.2 vs. 4.2 +/- 2.9, p = 0.01, AS: 0.5 +/- 0.3 vs. 2.8 +/- 2.7, p = 0.002, PI: 24.4 +/- 9.6 vs. 18.7 +/- 7.4, p = 0.07 and TNROI: 6.8 +/- 5.8 vs. 14.7 +/- 11, p = 0.02). Our study suggested that subconjunctival retention of C3F8 gas increased the success rate of trabeculectomy in rabbits in the short-term follow-up period.

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The difference in intraocular pressure (IOP) dynamics between trabeculectomy and topical instillation of timolol was compared in a rabbit ocular hypertension model. Twenty New Zealand white rabbits trabeculectomized with subconjunctival retention of 0.3 mL C3F8 gas in the right eyes were used as animal models. One week and three weeks after the operation, the left eyes of the rabbits were given three drops of 0.5% timolol, and IOP dynamics were compared between the two fellow eyes after intravenous infusion of 0.9% NaCl sterile solution. There were four parameters available in comparing IOP dynamics: Time Needed to Reach Peak IOP (TNRPI); Ascending Slope (AS); Peak IOP (PI); and Time Needed to Return to the Original IOP (TNROI). By this method, it was noted that, at the 7th day after the operation, the eyes trabeculectomized with subconjunctival retention of C3F8 gas had lower IOPs than the eyes that received topical instillation of timolol (baseline IOP: 14.7 +/- 4.2 vs. 19.5 +/- 2.5, p < 0.001, PI: 16.4 +/- 5.2 vs. 26.2 +/- 9.3, p < 0.001). In addition, at the 21st postoperative day, after intravenous infusion of 0.9% NaCl solution, the operated eyes showed less IOP spiking than the eyes that received topical instillation of timolol (TNRPI: 5.7 +/- 2.1 vs. 3.9 +/- 2.3, p = 0.014; AS: 0.8 +/- 0.5 vs. 2.7 +/- 2.6, p = 0.003; PI: 21.2 +/- 7.8 vs. 27.9 +/- 8.6, p = 0.014; and TNROI: 8.4 +/- 6.5 vs. 12.6 +/- 7.3, p = 0.06). These results suggested that trabeculectomy, rather than topical timolol, yielded better protection against IOP spiking in a transient rabbit ocular hypertension model.

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A man aged 51 years was found to have cytomegalovirus (CMV) retinitis in his right eye one year after heart transplant surgery. Ophthalmoscopy revealed a patch yellowish-white, granular, necrotic lesions admixed with flame-shaped intraretinal hemorrhage over the temporal lower retina. Anti-CMV IgM antibody was positive. The visual acuity improved from 20/200 to 20/20 within one month by CMV hyperimmune globulin therapy (cytotect, Biotest, FRG, 2 ml/kg every other day for two weeks). The retinal necrosis healed with permanent scar tissue formation. No other complications were noted after a fifteen month follow up. In this study, the clinical findings and fundus picture were presented, along with previous literature reviewed.

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OBJECTIVES: To study the bony structure of the optic canal and the vasculature of the intracanalicular optic nerve in human cadavers. MATERIALS AND METHODS: Gross and microscopic examinations were performed in 25 optic canals from 13 cadavers to study the pattern of vascular supply of the intracanalicular optic nerve. Neoprene latex was injected through the most proximal part of the ophthalmic artery in seven optic canals. The intracanalicular branches from the ophthalmic artery were carefully identified and quantified. Quantitative measurements of the canal length, canal thickness, canal transverse area, optic nerve transverse area, and subdural space were done for the other 18 canals by means of semiautomated morphometric analysis system. Each canal was divided into anterior, middle, and posterior parts for better visualization and measurement. RESULTS: The ophthalmic artery gives off three branches that supply the intracanalicular optic nerve: medial collateral branch, lateral collateral branch, and ventral branch. Each branch pierces the dura and then supplies the nerve through the pia mater. The middle medial wall was the thinnest bony part of the canal (0.31 +/- 0.06 mm). The optic canal, optic nerve, and subdural space transverse area varied at different transection levels. The narrowest space was in the middle part of the optic canal. The mean subdural cross-sectional space was only 1.84 mm2. This, multiplied by the average canal length (11.79 mm), can be considered the potential space for hemorrhage, optic nerve edema, or hematoma. CONCLUSIONS: The vasculature within the bony canal is extremely delicate. Due to the limitation of this space, even a tiny amount of blood or swelling of the nerve (21.69 mm3) may cause optic nerve compression. It appears that these vessels could easily be disrupted in closed head injury by a shearing or concussive force, leading to ischemic infarction of the optic nerve. Since the narrowest portion of the canal is in the middle portion, it is the middle part of the optic canal that is most critical in doing an optic canal decompression.

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We report three rare occurrences of late onset dysthyroid optic neuropathy. We reviewed each case in detail and found that these middle-aged patients developed onset of optic neuropathy 7 to 12 years following stabilization of clinically significant, stable ophthalmopathy. There was no corresponding reactivation of orbital inflammatory symptoms or signs. Characteristic of a Graves' ophthalmopathy, the vision was responsive to either corticosteroid or surgical decompression, or to a combination thereof. None of the patients had diabetes, hypertensive, or cardiovascular disease. We hypothesize that in these unique cases possible mechanical vascular factors may have induced decompensation of optic nerve function in otherwise stable disease.

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