methylcellulose and Ocular-Hypertension

To investigate the natural course of intraocular pressure (IOP) after small-incision cataract surgery with sodium hyaluronate 1% versus hydroxypropylmethylcellulose 2%.. Randomized clinical trial.. Eighty eyes of 40 consecutive patients with bilateral age-related cataract.. The patients were assigned randomly to receive sodium hyaluronate 1% or hydroxypropylmethylcellulose 2% during cataract surgery in the first eye. The second eye received the other ophthalmic viscosurgical device. The IOP was measured preoperatively and 30 minutes; 1, 2, 3, 4, 6, 8, and 20 to 24 hours; and 1 week postoperatively.. Postoperative IOP increase.. The highest mean IOP increase occurred at 8 hours postoperatively (5.3+/-6.4 mmHg) in the sodium hyaluronate 1% group and at 2 hours postoperatively (7.8+/-6.1 mmHg) in the hydroxypropylmethylcellulose 2% group. Overall, the IOP increase was higher with hydroxypropylmethylcellulose 2% (P = 0.005). Intraocular pressure spikes to > or =30 mmHg occurred in 5 eyes (13%) in the sodium hyaluronate 1% group and 13 eyes (33%) in the hydroxypropylmethylcellulose 2% group.. Sodium hyaluronate 1% and hydroxypropylmethylcellulose 2% caused significant IOP increases during the first 8 hours after cataract surgery. A single measurement at 6 hours postoperatively could detect all IOP spikes in the sodium hyaluronate 1% group. In the hydroxypropylmethylcellulose 2% group, a single measurement at 2 hours postoperatively could detect two thirds of IOP spikes.

Topics: Aged; Female; Humans; Hyaluronic Acid; Hypromellose Derivatives; Intraocular Pressure; Lens Implantation, Intraocular; Male; Methylcellulose; Ocular Hypertension; Phacoemulsification; Postoperative Period; Prospective Studies; Pseudophakia; Tonometry, Ocular

To evaluate the effects of the dispersive viscoelastic agents Ocucoat (hydroxypropyl methylcellulose 2%) and Viscoat (sodium chondroitin sulphate 4%-sodium hyaluronate 3%) on postoperative intraocular pressure (IOP) after bilateral small incision cataract surgery.. This prospective, randomised study comprised 80 eyes of 40 consecutive patients with age related cataract in both eyes scheduled for bilateral small incision cataract surgery. The patients were randomly assigned to receive Ocucoat or Viscoat during cataract surgery of the first eye. The second eye was operated later and received the other viscoelastic agent. Cataract surgery was performed with a temporal 3.2 mm sutureless posterior limbal incision, phacoemulsification, and implantation of a foldable silicone intraocular lens. The IOP was measured preoperatively as well as 6 hours, 20-24 hours, and 1 week postoperatively.. At 6 hours after surgery the mean IOP increased by 4.6 (SD 5.1) mm Hg in the Ocucoat group (p<0.001) and by 8.6 (8.1) mm Hg in the Viscoat group (p<0.001). The increase was significantly higher in the Viscoat group than in the Ocucoat group (p=0.004). Intraocular pressure spikes of 30 mm Hg or more occurred in two eyes in the Ocucoat and in nine eyes in the Viscoat group (p=0.023); 20-24 hours and 1 week postoperatively the mean IOP was not statistically different.. These findings indicate that Viscoat causes a significantly higher IOP increase and significantly more IOP spikes than Ocucoat in the early period after small incision cataract surgery.

Topics: Aged; Aged, 80 and over; Chondroitin; Chondroitin Sulfates; Double-Blind Method; Drug Combinations; Female; Humans; Hyaluronic Acid; Hypromellose Derivatives; Intraoperative Care; Male; Methylcellulose; Middle Aged; Ocular Hypertension; Phacoemulsification; Postoperative Complications; Postoperative Period; Prospective Studies; Viscosity

Sixty eyes with age-related cataract underwent extracapsular cataract extraction (ECCE) with posterior chamber intraocular lens (PC-IOL) implantation under similar conditions using hydroxypropyl methylcellulose (HPMC) (Oculose) (n = 20), sodium hyaluronate (Healon) (n = 20), or hyaluronic acid (IAL) (n = 20) as the viscoelastic (VE). Postoperative evaluation was performed for intraocular pressure (IOP), corneal thickness, and anterior chamber reaction at 6, 24, 48, 72 hours, and 10 days. Statistically-significant rises in IOP with IAL and Healon were observed at 6 and 24 hours; no such rises were observed with Oculose (P < .05). Seven eyes in the IAL group and six in the Healon group had IOPs greater than 22 mm Hg at 6 hours (range: 22 to 38 mm Hg and 22 to 28 mm Hg, respectively). A significant increase in average corneal thickness was observed in all of the 60 patients at 6 hours (18.5%). The average thickness decreased to 6.8% by day 10, with no intergroup variations. There were significantly fewer anterior chamber cells at 6 hours in the Healon group. We conclude that all three viscoelastics are equally useful for routine ECCE with PC-IOL implantation. However, IAL and Healon do cause an early postoperative IOP increase, which, though transient, should be treated.

Topics: Anterior Chamber; Cataract Extraction; Humans; Hyaluronic Acid; Hypromellose Derivatives; Intraocular Pressure; Lenses, Intraocular; Methylcellulose; Ocular Hypertension; Postoperative Complications; Single-Blind Method

We conducted a study to evaluate the shortterm effect on intraocular pressure (IOP) following extracapsular cataract extraction using either sodium hyaluronate 1% or hydroxypropyl methylcellulose 2%. In both groups a non-significant rise in IOP at day 1 was followed by a significant decline in IOP at day 3 to values below the pre-operative level (p < 0.05). At day 7 both groups had returned to pre-operative values. Post-operatively, spikes in intraocular pressure (> 25 mmHg) were seen equally in both groups. Patients with pre-operatively diagnosed open-angle glaucoma, high myopia and diabetic retinopathy are considered to be at high risk concerning post-operatively elevated IOP, but with small variation these patients followed the main trend.

Topics: Adult; Aged; Aged, 80 and over; Cataract Extraction; Diabetic Retinopathy; Female; Glaucoma, Open-Angle; Humans; Hyaluronic Acid; Hypromellose Derivatives; Intraocular Pressure; Lenses, Intraocular; Male; Methylcellulose; Middle Aged; Myopia; Ocular Hypertension; Ophthalmic Solutions; Prospective Studies; Risk Factors

To examine the change in intraocular pressure (IOP) within 1 week of phacoemulsification and foldable posterior chamber intraocular lens (PC IOL) implantation using Adatocel (hydroxypropyl methylcellulose 2% [HPMC]).. Department of Ophthalmology, University of Sciences, Faculty of Medicine, Pécs, Hungary.. In this prospective study, the IOP in 118 eyes of 118 patients (57 men, 61 women, mean age 68 years +/- 7.8 [SD]) with no history of glaucoma was assessed by Goldmann applanation tonometry 2 to 3, 6 to 8, and 22 to 24 hours and 1 week after uneventful phacoemulsification and PC IOL implantation. The effect of the removal of Adatocel ("partial removal" from the anterior chamber [AC] only versus "complete removal" from behind of the IOL as well), the lens type (Medicontur 601 HP versus Bausch & Lomb Hydroview), and the type of anesthesia (topical versus parabulbar) were compared. Statistical analysis was performed using the Student t test, and P< or =.05 was considered statistically significant.. The mean preoperative IOP was 13.83 +/- 2.5 mmHg. There were no significant differences at any time in postoperative IOP measurements between the 2 IOL types and the 2 modes of anesthesia. At 2 to 3 hours, 6 to 8 hours, and 22 to 24 hours, the IOP was significantly higher in the 30 eyes in which the Adatocel was partially removed (from the AC only) than in the 88 eyes in which it was completely removed (from behind the PC IOL as well) (P< or =.05, P< or =.01, and P< or =.001, respectively).. Severe postoperative IOP spikes in nonglaucomatous patients after uneventful phacoemulsification cataract surgery are rare. The type of implanted PC IOL and the mode of anesthesia had no significant effect on postoperative IOP. Total removal of the ophthalmic viscosurgical device, even when using HPMCs such as Adatocel, is necessary to prevent postoperative IOP spikes.

Topics: Adult; Aged; Aged, 80 and over; Anesthesia, Local; Female; Humans; Hypromellose Derivatives; Intraocular Pressure; Lens Implantation, Intraocular; Male; Methylcellulose; Middle Aged; Ocular Hypertension; Ophthalmic Solutions; Phacoemulsification; Postoperative Complications; Prospective Studies; Tonometry, Ocular

To characterize a new animal model of moderate chronic hyperpressure obtained by obstruction of the iridocorneal angle (ICA) in the minipig.. Intraocular hyperpressure was induced in one eye (left) using an injection of methylcellulose (4%) in the anterior chamber of six healthy adult minipigs. Intraocular pressure (IOP) was measured before injection and at D+60 and D+180. The clinical condition thus created was regularly assessed with the following procedures: fundus photography, electroretinography (ERG) to evaluate retinal function, scanning laser ophthalmoscopy (SLO) angiography to measure the arteriovenous filling times (AVFT). Optical microscopy was also performed to evaluate iridocorneal angle and inner retinal layers.. In all instances the injection produced a significant increase in the IOP accompanied by a mydriasis, as well as a significant increase in the AVFT and reduction (abolition in some cases) in the i-wave of the ERG. Fundus examination also revealed a blurred aspect and reduction in the calibre of the retinal blood vessels. Similarly, all experimental eyes showed, at optical microscopy, obstruction of the ICA as well a significant loss of of retinal ganglion cells.. Our results suggest that the above pathophysiological processes, triggered by the induced hyperpressure, share many similarities with human chronic open-angle glaucoma. Consequently, our model, which is very easy to create, could be used to test new therapeutic agents such as neuroprotective drugs.

Topics: Animals; Disease Models, Animal; Electroretinography; Fluorescein Angiography; Glaucoma, Open-Angle; Methylcellulose; Ocular Hypertension; Swine; Swine, Miniature

To evaluate an animal model used to study intraocular pressure (IOP) development after aqueous exchange with several commercially available ophthalmic viscosurgical devices (OVDs).. Department of Preclinical Ophthalmology, Pharmacia & Upjohn, Uppsala, Sweden.. Albino rabbits (New Zealand White) were used. Aqueous humor (50 microL) was exchanged with 8 OVDs. The IOP was measured every second hour for 12 hours and then 24, 48, and 72 hours after aqueous exchange using a pneumotonometer (Modular One, Bio-Rad Digilab Inc). A minimum of 7 eyes was used for each OVD. Healon was used as control in 1 eye in all experiments. The OVDs were Viscoat (chondroitin sulfate-sodium hyaluronate), Provisc (sodium hyaluronate), Biolon (sodium hyaluronate), Healon GV, Healon5, Ophthalin (sodium hyaluronate), Ocucoat (hydroxypropyl methylcellulose), and Ivisc (sodium hyaluronate).. All OVDs caused a postoperative increase in IOP. At 24 hours, the IOP was at the preoperative levels. However, there was considerable variation in the maximum IOP value and when this value occurred. The maximum value appeared to depend on the concentration of the rheologically active substance in the product and the time of the average molecular mass. There was also an increase in central corneal thickness, with a maximum increase 24 hours after the exchange but a large variation among animals.. The animal model appears to be useful for comparing various OVDs, and the results may serve as a guide for the design of clinical studies of new products.

Topics: Animals; Anterior Chamber; Aqueous Humor; Chondroitin Sulfates; Circadian Rhythm; Cornea; Female; Hyaluronic Acid; Hypromellose Derivatives; Injections; Intraocular Pressure; Male; Methylcellulose; Ocular Hypertension; Ophthalmologic Surgical Procedures; Prognosis; Protease Inhibitors; Rabbits; Tonometry, Ocular

The effects of ocular acute hypertension experimentally induced on the astrocyte cells of rat have been studied. Evaluation was made of the damage to the chromatin of those cells by means of cytochemical (haematoxylin-eosin) analysis and of the state of fragmentation of the DNA by means of the TUNEL technique as well as the protective effect of the peroxide scavenger, troxol, on those events.

Topics: Acute Disease; Animals; Astrocytes; Chromatin; DNA Fragmentation; In Situ Nick-End Labeling; Intraocular Pressure; Male; Methylcellulose; Ocular Hypertension; Optic Nerve; Rats; Rats, Wistar

The effects of experimental hypertension on retinal cells were studied. Evaluation was made of IOP levels and degree of cell damage by cytochemical and DNA analysis, and degeneration modes: necrosis and apoptosis.

Topics: Acute Disease; Animals; Apoptosis; DNA; Follow-Up Studies; Intraocular Pressure; Male; Methylcellulose; Necrosis; Ocular Hypertension; Rats; Retina; Retinal Degeneration

There are many unanswered questions about chronic glaucoma which cannot be investigated in the available animal models. The present experiments were designed to develop a rabbit model of chronic intraocular hypertension with characteristics similar to human chronic glaucoma by ligating vortex veins or by making single or multiple intraocular injections of 0.5% or 1% alpha-chymotrypsin, 20% chondroitin sulphate, 2% hydroxypropyl methylcellulose, 2% sodium carboxymethylcellulose or 1% or 2% methylcellulose. Evaluation was based on the clinical findings, intraocular pressure and the retrograde axoplasmic transport function of the optic nerve using a horseradish peroxidase histochemical technique. Most methods either failed to produce moderate chronic intraocular hypertension or were associated with other complications. However, a reliable and relatively long period (eight weeks) of intraocular hypertension was developed by a series of four intra-anterior chamber injections of 1% or 2% methylcellulose. This model has been proved suitable for the study of structural and functional damage to the retina and optic nerve caused by chronic glaucoma.

Topics: Animals; Anterior Chamber; Cell Count; Chronic Disease; Disease Models, Animal; Female; Intraocular Pressure; Male; Methylcellulose; Ocular Hypertension; Rabbits

Methylcellulose has been used since 1976 to prevent damage to the corneal endothelium during operations for implantation of intraocular lenses. With a 2 per cent solution of methylcellulose it is possible to maintain a space between the cornea and iris even if vitreous pressure is present to operate without risk to the corneal endothelium. This paper demonstrates the safety of the intraocular use of methylcellulose based on the results of over 700 operations. The substance is cheap, universally available, and can be easily prepared for intraocular use.

Topics: Acetazolamide; Eye; Humans; Lenses, Intraocular; Methods; Methylcellulose; Ocular Hypertension

Topics: Animals; Antihypertensive Agents; Glaucoma; Intraocular Pressure; Mannitol; Methylcellulose; Ocular Hypertension; Pharmacology; Rabbits; Research; Tonometry, Ocular