Peribulbar and retrobulbar anesthesia with prilocaine: a comparison of two methods of local ocular anesthesia

Prilocaine (Citanest) has been shown to be a satisfactory alternative to lignocaine, with certain important advantages, including superior diffusion. The latter may be especially important in peribulbar anesthesia, where the level of diffusion is a critical factor in providing a timely, high-quality block. In a prospective randomized study, we compared the effectiveness of peribulbar vs retrobulbar administration of prilocaine. Eighty-seven patients undergoing elective intraocular surgery were randomized to receive either retrobulbar or peribulbar anesthesia with prilocaine 3% with felypressin and hyaluronidase. Pain of injection, akinesia, and anesthesia were evaluated at predetermined intervals after injection. Except for the fact that lid akinesia occurred earlier in the peribulbar group, there was no difference in the quality or rate of onset of overall akinesia in the two groups. Nor were there any differences in the pain associated with injection. Both groups had excellent operative anesthesia and akinesia.     

Prevalence and management of elevated intraocular pressure in patients with Graves' orbitopathy

AIMS: To investigate the prevalence and to discuss the necessity of treating elevated intraocular pressures (IOP) in patients with Graves' orbitopathy (GO). In addition, to study the effects of orbital decompression and extraocular muscle surgery on IOP. METHODS: The records of consecutive patients with GO referred in a 5 year period were studied and those selected, in which glaucoma medication had been prescribed, or a diagnosis of primary open angle glaucoma (POAG) or of ocular hypertension (> or = 22 mm Hg) (OH) had been made. The necessity of treating these patients with glaucoma medication was questioned and the effects of corticosteroids, orbital decompression, and extraocular muscle surgery on the IOP were evaluated. RESULTS: Of 482 patients with GO, 23 (4.8%) met the inclusion criteria. Four patients (0.8%) had POAG, four had elevated IOPs and visual field defects consistent with dysthyroid optic neuropathy, and 15 (3.1%) had only elevated IOPs. Five patients with OH showed a permanent drop of IOP after orbital decompression, two had a marked decrease of their IOP after recession of the inferior rectus muscle. CONCLUSIONS: POAG has the same prevalence in the general Dutch population as in the GO subgroup. The combination of elevated IOPs and visual field defects in GO patients may be attributed to other mechanisms than obstructed aqueous outflow in the trabecular meshwork and should be treated accordingly. Orbital decompression and extraocular muscle surgery may lower the IOP in patients with GO.     

Changes in anterior chamber depth and intraocular pressure after phacoemulsification and posterior chamber intraocular lens implantation

BACKGROUND AND OBJECTIVE: To determine anterior chamber depth (ACD) and intraocular pressure (IOP) following uncomplicated cataract extraction with phacoemulsification and posterior chamber intraocular lens (IOL) implantation. PATIENTS AND METHODS: The ACDs and IOPs of 56 patients were prospectively evaluated after phacoemulsification and IOL implantation. Measurements of ACD were performed using ultrasonography and measurements of IOP were performed using a Goldmann applanation tonometer preoperatively and at 1 week and 1, 3, 6, and 9 months postoperatively. RESULTS: The mean IOP had decreased and the mean ACD had increased significantly by 1 month postoperatively (P < .03 and P < .01, respectively). Between 1 and 3 months, a significant increase in ACD (P < .05) and decrease in IOP (P < .01) was also observed. The ACD peaked (3.51 +/- 0.45 mm) and the IOP reached its lowest value (10.05 +/- 2.23 mm Hg) at 3 months postoperatively. The reduction in IOP and increase in ACD remained significant during the follow-up period, compared with the preoperative values. CONCLUSION: These results suggest that increases in ACD and decreases in IOP occur in selected patients after uncomplicated cataract extraction by phacoemulsification with IOL implantation.     

Mitomycin-C in congenital glaucoma

BACKGROUND AND OBJECTIVE: To evaluate the adjunctive use of mitomycin-C (MMC) during trabeculotomy and trabeculectomy for eyes with high-risk congenital glaucoma. PATIENTS AND METHODS: A prospective, randomized, double-blind study was performed to compare the effect of a single, 4-minute intraoperative exposure to 0.2 mg/ml (group 1) or 0.4 mg/ml (group 2) of MMC on trabeculotomy with trabeculectomy in 16 high-risk cases (30 eyes) of congenital glaucoma. RESULTS: The preoperative and final postoperative intraocular pressures (IOPs) of the two groups did not differ significantly. At the final follow-up, IOP control (< 21 mm Hg) without medications was achieved in 60% of the eyes in group 1 and in 86.67% of the eyes in group 2 (P = 21). With medication, IOP control was achieved in 86.7% of the eyes of each group. In both groups, the rate of surgical failure was 13.3%. Avascular, thin, sharply demarcated blebs were noted in 33.3% of the eyes from group 1 and in 66.67% of those from group 2 (P = .14). Intraoperative and postoperative hyphema and postoperative hypotony were the complications encountered in both groups, whereas serous choroidal detachment and wound leakage were seen only in group 2. CONCLUSIONS: Intraoperative MMC applied at a concentration of 0.2 mg/ml controlled postoperative IOP as effectively as a 0.4-mg/ml concentration in high-risk cases of congenital glaucoma, but with a lower incidence of complications and thin-walled blebs.     

Postcataract ptosis. A randomized, double-masked comparison of peribulbar and retrobulbar anesthesia

PURPOSE: A randomized, double-masked study of 317 patients was conducted to determine if the incidence of postcataract ptosis is greater with retrobulbar or two-injection peribulbar injection anesthesia. METHODS: Surgery consisted of a planned extracapsular extraction with posterior chamber lens implantation, and no superior rectus bridle suture was used. Ptosis was quantitatively documented preoperatively and postoperatively at 1, 2, 5, and 90 days by the surgeon, photographically at 90 days by a masked observer, and subjectively by the patients. Postcataract ptosis was defined as a drop in the lid margin of 2 mm or greater after correcting for any change in the fellow eye. RESULTS: The incidence of ptosis at 90 days in patients given peribulbar anesthesia was 5.8% and in patients given retrobulbar anesthesia 5.5%, and this difference was not statistically significant (P = 0.90). Eighteen percent of patients in both groups reported a change in the appearance of their eyelids. There was a moderate, positive correlation among patients who reported a change in their lid position and objective measurements of ptosis. Preoperative clinical measurements of vertical lid fissure width and levator function, and the appearance of the lid crease or superior sulcus were not predictive for the development of postoperative ptosis at 90 days; the best predictor was the presence of ptosis in the immediate postoperative period. CONCLUSION: The incidence of postcataract ptosis is the same whether two injection peribulbar or retrobulbar anesthesia is used.     

Chronic use of apraclonidine decreases its moderation of post-laser intraocular pressure spikes

OBJECTIVE: The purpose of the study is to investigate the efficacy of 1.0% apraclonidine in preventing intraocular pressure (IOP) spike after argon laser trabeculoplasty (ALT) in patients on chronic apraclonidine therapy compared with patients not on chronic apraclonidine use. DESIGN: The study design was a prospective study. PARTICIPANTS: This study consisted of 231 consecutive eyes of patients with primary open-angle glaucoma undergoing ALT: 70 eyes (30%) were started on a regimen including chronic apraclonidine 0.5% use (group A) and 161 eyes (70%) were started on a regimen without chronic apraclonidine 0.5% use (group B). INTERVENTION: Both groups received one drop of apraclonidine 1.0% 15 minutes before ALT to 180 degrees of previously untreated trabecular meshwork. Intraocular pressure was measured before the procedure and at 5 minutes, 1 hour, and 24 hours after the laser treatment. MAIN OUTCOME MEASURES: Incidences of an IOP spike and mean IOPs at 5 minutes, 1 hour, and 24 hours after the laser treatment were compared between the two groups. Multivariate logistic regression analysis also was carried out to identify the significant risk factors for post-ALT IOP spikes despite prophylactic apraclonidine 1.0% treatment. RESULTS: The incidences of IOP spikes greater than 0 mmHg, greater than 2 mmHg, and greater than 5 mmHg at 1 hour after ALT were 32.9%, 22.9%, and 12.9%, respectively, in group A versus 13.7%, 11%, and 3.1%, respectively, in group B (P = 0.0007, P = 0.009, and P = 0.004). Chronic apraclonidine 0.5% use was found to be the only significant risk factor for IOP spikes at 1 hour after ALT by multivariate logistic regression analysis. CONCLUSIONS: The incidences of IOP spikes in group A were significantly greater than in group B and approached the reported incidences of IOP spikes without perilaser apraclonidine prophylaxis. This indicates that peri-ALT apraclonidine is relatively ineffective in patients with chronic apraclonidine 0.5% use (group A) compared with patients without chronic apraclonidine use (group B), presumably because of saturation of the ocular alpha-2 receptors with apraclonidine in patients with chronic apraclonidine use. Therefore, in patients receiving chronic apraclonidine therapy, it is especially important to monitor their post-ALT IOPs and to be prepared to treat postlaser IOP spikes using agents other than apraclonidine.     

Routine psychophysiological screening of 384 men with erectile dysfunction

BACKGROUND AND OBJECTIVE: To determine the efficacy of combined phacoemulsification--trabeculectomy in preventing early postoperative increases in intraocular pressure (IOP). PATIENTS AND METHODS: Eighty patients were enrolled in a prospective cohort study. Thirty-six patients with cataracts and uncontrolled glaucoma underwent combined phacoemulsification--trabeculectomy, and 44 patients with cataracts underwent phacoemulsification alone. The operations were performed in a standardized manner by one surgeon. IOP was measured at 4 hours, 1 day, and 7 days after surgery. The need for intervention (digital massage, medications) and the presence of complications were documented. RESULTS: Four hours after surgery, 5.5% of patients undergoing the combined procedure had IOPs greater than 30 mm Hg, compared with 22.7% of phacoemulsification patients (P < .05). No significant difference in IOP was found between the groups at postoperative day 1 or day 7. CONCLUSION: These results suggest that combined phacoemulsification-trabeculectomy protects against early postoperative elevations in IOP. This finding may influence the surgical management of cataracts in patients with poorly controlled glaucoma and significant compromise of visual field or optic nerve.     

Rate of cerebrospinal fluid formation, resistance to reabsorption of cerebrospinal fluid, brain tissue water content, and electroencephalogram during desflurane anesthesia in dogs

Propofol decreases intraocular pressure (IOP) and the IOP response to laryngoscopy and intubation, but the mechanisms responsible for this effect have not been reported. The present study examined the effect of propofol on IOP, intraocular fluid formation and outflow facility, and intraocular compliance. Twenty-two white New Zealand rabbits were anesthetized with halothane (0.8%-1.0% inspired concentration) in nitrous oxide (2 L/min) and oxygen (1 L/min). Muscle paralysis was established with pancuronium, and the lungs were mechanically ventilated through a tracheal tube. Twelve rabbits examined under these conditions served as controls. In the treatment group (n = 10), 6 mg/kg propofol followed by 18 mg.kg-1 x h-1 propofol intravenously was added to halothane/nitrous oxide/oxygen anesthesia. In both groups, a series of intraocular infusions was made via a 30-gauge needle in the anterior chamber, and IOP, the rate of aqueous humor formation (Fa), and trabecular outflow facility (Ctr) were determined using conventional analysis. These same measures, as well as intraocular compliance, were determined using a new method of analysis adapted from the manometric technique for determining cerebrospinal fluid dynamics. IOP was 11.3 +/- 1.8 mm Hg (mean +/- SD) in halothane-anesthetized controls and decreased to 9.4 +/- 2.2 mm Hg when propofol was added to halothane anesthesia (P < 0.05). By conventional analysis, Fa was 2.82 +/- 0.94 microL/min and Ctr was 0.121 +/- 0.044 microL.min-1 x mm Hg-1 in controls. After addition of propofol, Fa decreased by 24% to 2.15 +/- 0.62 microL/min (P < 0.05) and Ctr decreased by 18% to 0.099 +/- 0.034 microL.min-1 x mm Hg-1 (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Menadione induces changes in the membrane electrical properties associated with downregulation of insulin receptors in human erythrocytes

BACKGROUND AND OBJECTIVE: To investigate the course of the intraocular pressure (IOP) in nonglaucomatous patients with pseudoexfoliation (PSX) syndrome after cataract surgery. PATIENTS AND METHODS: In a prospective age-matched controlled clinical study, 23 consecutive patients with PSX were studied and compared with a control group of 23 patients. The IOP was measured by applanation tonometry preoperatively, and postoperatively on day 1, after 4 weeks, and after 6 months. All patients were operated on with a self-sealing 7-mm scleral tunnel incision, phacoemulsification, and posterior chamber intraocular lens (IOL) implantation. RESULTS: Preoperatively the IOP was similar between both groups (P = .962). At the first postoperative day the IOP was below 22 mm Hg in all cases. After 4 weeks and 6 months a mean decrease of 3.88 mm Hg (P = .001) in the control group and of 3.15 mm Hg (P = .002) in the PSX group was observed; this difference was not statistically significant (P = .543). CONCLUSIONS: At 1 day postoperatively no pressure increase was observed in the eyes with PSX after scleral tunnel incision and phacoemulsification. Six months after cataract extraction with IOL implantation, the tension level decreased in the presence of PSX similarly as in normal eyes.     

Bioavailability and pharmacokinetic disposition of tacrine in elderly patients with Alzheimer''s disease

PURPOSE: The Baerveldt glaucoma implant is an aqueous shunting device with large surface area that is installed through a single-quadrant conjunctival incision. A rabbit model of the Baerveldt implant was created to obtain serial histology and clinical information over 1 year. METHODS: Modified versions of the Baerveldt implant (110 or 160 mm2) were implanted in 18 normal New Zealand white rabbit eyes. The rabbits were examined periodically and their intraocular pressures (IOPs) recorded. They were killed at monthly intervals to obtain histology of the bleb capsules. RESULTS: Thin capsules were present at 1 month, which consisted of lamellar collagen deposition surrounded by a granulomatous reaction with multinucleate giant cells. Inflammatory cells (probably macrophages) were scattered on the inner bleb surface. The granulomatous reaction resolved after 4 months. Subsequently, capsule thickness and cellularity remained relatively stable, although the collagen stroma became less compact over time. Sixteen rabbit eyes had initial IOP reductions of > or = 3 mm Hg compared with fellow eyes, which persisted up to 4 weeks postoperatively. Seven eyes (39%) exhibited a hypertensive phase (IOP exceeded that of fellow eye by > or = 3 mm Hg) from 2 weeks to 3 months postoperatively. CONCLUSION: The Baerveldt explant is surrounded by a fibrous capsule that matures over time. The bleb histology in the rabbit model is similar to that described with the Molteno implant in primates and humans, except for the eventual development of a fibroblastic inner lining in the rabbit model. This contrasts with primate and human models, in which the inner lining remains an open mesh.     

Topical plus subconjunctival anesthesia for phacotrabeculectomy: one year follow-up

PURPOSE: To evaluate the results of topical plus subconjunctival anesthesia for phacotrabeculectomy surgery and postoperative glaucoma control over 1 year. SETTING: Pacific Eye Center, Brisbane, Australia. METHODS: In this retrospective study of consecutive patients with glaucoma and cataract, topical plus subconjunctival anesthesia was used for combined phacoemulsification, posterior chamber intraocular lens implantation, and trabeculectomy (phacotrabeculectomy). Patients with proliferative diabetic retinopathy or neovascular glaucoma were excluded. RESULTS: Thirty-eight eyes had phacotrabeculectomy using topical plus subconjunctival anesthesia over 2 years. Patients reported no discomfort intraoperatively or postoperatively, and none required intravenous sedation. Eighty-one percent of patients achieved a best corrected visual acuity of 20/40 or better 6 months after surgery. Mean drop in intraocular pressure (IOP) was 5.91 mm Hg at 3 months and 5.86 mm Hg at 12 months, at which time IOP was controlled without additional medication in 72% of patients. There were no serious complications postoperatively. CONCLUSION: In this series, no patient reported intraoperative or postoperative discomfort and surgical results were excellent in terms of visual outcome and IOP control.     

Intraocular pressure fluctuations during scleral buckling surgery

PURPOSE: The purposes of this study are to measure real-time intraocular pressure (IOP) during scleral buckling and to determine the effects of elevated IOPs on ocular perfusion. PATIENTS AND METHODS: A standard 4-mm, 20-gauge infusion cannula was inserted through the pars plana, connected to a standard hemodynamic monitoring unit with an electronic pressure transducer, and calibrated. The authors measured real-time IOP in 20 eyes undergoing scleral buckling surgery for primary rhegmatogenous retinal detachments and determined the IOP required to close the central retinal artery. Pressure measurements were read from the monitor videoscreen intraoperatively and from a continuous paper tracing postoperatively. RESULTS: The patients ranged in age from 24 to 88 years (mean, 59.7 years). The highest IOP elevations occurred during scleral depression and cryopexy, ranging up to 210 mmHg (mean, 116 mmHg). Pressures at which the central retinal artery closed ranged from 48 to 110 mmHg (mean, 79.2 mmHg). Manipulations of the globes caused IOPs greater than the central retinal artery perfusion pressures in 13 of the 20 patients. The duration of pressures in excess of the central retinal artery perfusion pressure ranged from 6 to 402 seconds (mean, 118.8 seconds). There were no intraoperative or postoperative complications from the infusion cannula. CONCLUSIONS: Conventional scleral buckling surgery causes wide fluctuations in IOP and may impair ocular perfusion. Additional studies are needed to determine the long-term consequences of these pressure elevations.     

Long-term non-invasive measurement of intraocular pressure in the rat eye

To study the optic neuropathy associated with glaucoma, a system for accurate, reliable, and non-invasive monitoring of intraocular pressure (IOP) is required. Of particular interest is the effect of sampling frequency on IOP. To address this issue, ten adult male brown Norway rats (group 1) were acclimatized to a 12-h/12-h light/dark cycle. On 20 days over a 30-day period, rats were anesthetized with short-acting isoflurane (Forane) inhalant anesthesia and IOP for each eye was determined by averaging 15 valid individual readings obtained with a TonoPen 2 tonometer. The last 12 measurement sessions were performed on a daily basis. To determine the minimum tolerable interval between IOP measurement sessions, a second group of 10 animals (group 2) was acclimatized in the same manner as group 1, and IOP was measured every 4 days over a period of 80 days. Next, IOP was measured every 4 days over a period of 28 days, and finally, every 2 days over a period of 19 days. For all group 1 measurements, there was no statistically significant difference between the right and left eye IOP, 14.75 +/- 1.08 (SEM) and 14.90 +/- 1.09 mm Hg, respectively. However, daily measurements produced a steady decrease in IOP and gradual weight loss. For group 2, overall mean right and left eye IOPs were 15.24 +/- 1.28 (SEM) and 15.12 +/- 1.26, respectively and were not significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)     

Topical versus peribulbar anesthesia in cataract surgery

PURPOSE: To compare the use of topical anesthesia with that of peribulbar anesthesia in cataract surgery. SETTING: Quinze-Vingts Hospital, Paris, France. METHODS: This prospective study comprised 45 patients who had phacoemulsification and intraocular lens implantation in both eyes with 1 to 9 months between surgeries. Each patient had peribulbar anesthesia for one surgery and topical anesthesia for the other. The anesthesia method for the first eye was randomly selected. After surgery, patients were asked to rate their pain and whether they preferred one anesthesia technique over the other. RESULTS: When topical anesthesia was given, 82.2% of patients required no intravenous medications. Overall, 62.2% preferred topical over peribulbar anesthesia, with most patients citing the lack of periocular injection as the reason. CONCLUSION: Despite the increased technical difficulty, topical anesthesia proved an effective alternative to peribulbar anesthesia for cataract surgery that avoids the risks of periocular injection and reduces the need for intravenous medications.     

Immediate argon laser peripheral iridoplasty as treatment for acute attack of primary angle-closure glaucoma: a preliminary study

OBJECTIVE: This study aimed to examine the intraocular pressure (IOP)-lowering effects and safety of immediate argon laser peripheral iridoplasty (ALPI) as a first-line treatment for acute primary angle-closure glaucoma (PACG). DESIGN: A prospective cohort study. PARTICIPANTS: Ten consecutive patients with their first attack of PACG, with IOP of 40 mmHg or greater, were recruited into the study. INTERVENTION: On presentation, each patient received topical pilocarpine (4%) and timolol (0.5%) and immediate ALPI as primary treatment. The IOPs at 15, 30, and 60 minutes after ALPI were documented by applanation tonometry. When the corneal edema had settled, laser peripheral iridotomy was performed as a definitive treatment. MAIN OUTCOME MEASURES: The IOP, corneal edema, and complications from ALPI were measured. RESULTS: The mean IOP of this group of patients was reduced from 59.5+/-10.4 mmHg to 28.7+/-14.9 mmHg at 15 minutes, 21.7+/-13.1 mmHg at 30 minutes, and 16.0+/-9.4 mmHg at 60 minutes after ALPI. No complications from the laser procedure were encountered during the study period. In nine of the ten patients, the corneal edema cleared up 1 hour after ALPI. In the remaining patient, the cornea cleared up 2 hours after ALPI. CONCLUSION: From this preliminary study, immediate ALPI, without adjunctive systemic antiglaucoma treatment, appeared to be very effective in controlling the IOP and returning corneal clarity in acute PACG. Its safety also appeared reassuring and did not have the risks associated with conventional systemic therapies.     

Propofol and alfentanil prevent the increase in intraocular pressure caused by succinylcholine and endotracheal intubation during a rapid sequence induction of anesthesia

The increase in intraocular pressure (IOP) associated with succinylcholine (Sch) has made its use in patients with open globe injuries controversial. Studies that have examined techniques to prevent the increase in IOP due to Sch have shown a larger increase in IOP from the stimulus of laryngoscopy and endotracheal intubation. The purpose of our study was to examine whether the combination of propofol and alfentanil would prevent the increase in IOP due to Sch as well as endotracheal intubation during a rapid sequence induction of anesthesia. Sixty patients were randomized to receive either thiopental 5 mg/kg and Sch 1.5 mg/kg (Group I), propofol 2 mg/kg and Sch 1.5 mg/kg (Group II), or propofol 2 mg/kg, alfentanil 40 micrograms/kg, and Sch 1.5 mg/kg (Group III). The IOP was measured continuously from baseline awake (control) values until 15 s after successful intubation. All three groups had a significant decrease in IOP with the induction of anesthesia. Succinylcholine produced a consistent increase in IOP from the postinduction low in Groups I and II, but this increase was not significantly higher than baseline. The postintubation IOPs in Groups I and II were significantly higher than baseline (P < 0.001). During the entire study period, the IOP in Group III never increased above baseline. The IOP in Groups I and II had already begun to decline by 15 s postintubation, suggesting that laryngoscopy and intubation have the greatest effect on increasing IOP. We conclude that the combination of propofol and alfentanil prevents the increase in IOP from Sch as well as the increase associated with endotracheal intubation during a rapid sequence induction of anesthesia.     

Digital palpation of intraocular pressure

BACKGROUND AND OBJECTIVE: Previous studies investigating the accuracy of digital palpation through the eyelids to estimate intraocular pressure (IOP) have shown disappointing results. In this study, the accuracy of digital assessment of IOP by palpation of the bare cornea is investigated. MATERIALS AND METHODS: The IOP of a cadaveric eye model was varied from 5 to 40 mm Hg in increments of 5 mm Hg. Two examiners, one experienced and one inexperienced, digitally palpated the corneas and estimated IOP. The results were compared before and after a 1-hour training session. RESULTS: Prior to the training session, the experienced examiner guessed correctly 46% of the time and was correct within 5 mm Hg 100% of the time. The inexperienced examiner guessed correctly 21% of the time and was within 5 mm Hg 62% of the time. After the training session, the experienced examiner's score did not significantly (38% correct, 88% within 5 mm Hg, P = .05. CONCLUSIONS: Digital assessment of IOP by palpation of bare cornea is accurate when performed by experienced individuals. A minimal amount of training using the eye model may improve one's accuracy.     

Measuring sexual harassment: development and validation of the Sexual Harassment Inventory

Recent studies have suggested that intravenous infusion of fenoldopam, a selective dopamine-1 receptor agonist, elevates intraocular pressure (IOP) in man. This study evaluated the effect of intravenous fenoldopam on IOP, aqueous humor outflow facility and gonioscopy in 12 healthy human subjects. Three doses (0.2, 0.5 and 1.0 microg/kg/min) were infused for 120 minutes in a double masked, placebo controlled, four-way crossover design. IOP was measured every 20 minutes in the supine position and every 40 minutes while sitting during the drug and placebo infusions. Tonography and gonioscopy were performed at baseline and after 120 minutes of infusion. Compared to placebo, IOP increased by 3.5 mm Hg (32%) for the lowest dose, 5.8 mm Hg (46%) for the intermediate dose, and 6.9 mm Hg (55%) for the highest dose (p<0.05 for all three doses). IOP returned to baseline within 30 minutes of stopping the infusion. The outflow facility decreased from baseline by 26% after 120 minutes of infusion for all drug doses. In contrast, outflow facility increased from baseline by 11% during placebo infusion. Compared to placebo, the fenoldopam induced changes in outflow were statistically significant (p<0.05). There was no change in the gonioscopic appearance of the anterior chamber angle during the infusion. This study shows that systemic administration of a selective dopamine-1 receptor agonist causes a significant dose-dependent increase in IOP that can be explained in part by diminished outflow facility. These results support a role for the dopamine-1 receptor in the modulation of IOP in general and suggest modulation of aqueous humor outflow by dopaminergic receptors.     

Short-and long-term effect of clear corneal incisions on intraocular pressure

PURPOSE: To evaluate short- and long-term intraocular pressure (IOP) after cataract surgery using clear corneal incision to assess whether there is a statistically significant postoperative IOP decrease. SETTING: Advanced Vision Care, West Hills, California. METHODS: We retrospectively 135 eyes of 89 randomly selected patients who had scleral tunnel or clear corneal cataract surgery with a follow-up of at least 6 months. Patients with pre-existing glaucoma were excluded. RESULTS: In the clear corneal group (n = 84), mean IOP was statistically significantly lower (P = .019) 12 months after surgery than preoperatively (13.65 versus 15.57 mm Hg). Although there was a trend toward decreased IOP in the scleral tunnel incision group (n = 51), the difference was not statistically significant (P = .178). CONCLUSION: We found a trend toward lower IOP that, if permanent, raises serious implications about the necessity of combined procedures in patients with both glaucoma and cataract.