PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Intraocular fluid”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 739 records · Page 41Linked to original sources

Pathogenic implications of subretinal gas migration through pits and atypical colobomas of the optic nerve.

OBJECTIVE: To describe subretinal migration of gas and silicone oil in a series of patients with congenital cavitary optic disc anomalies and to further clarify the pathogenesis of the associated maculopathy. METHODS: Medical records of 4 female patients, aged 8 to 34 years, who developed subretinal gas migration after vitreous surgery for macular detachment associated with cavitary optic disc anomalies were reviewed. A theoretical model was used to calculate the pressure differential required to induce subretinal gas migration through an optic pit. RESULTS: The 4 patients had bilateral atypical optic nerve colobomas or a unilateral large optic pit. A definite defect in the tissue overlying the disc excavation could be seen in one eye, and intraoperative drainage of subretinal fluid through the disc anomaly was possible in all cases. Subretinal migration of gas or silicone oil was seen intraoperatively in one case and first appeared between 1 and 17 days postoperatively in the remaining cases. Theoretical calculations suggest that the pressure differential required for migration of gas through a small defect in the roof of a cavitary disc lesion is within the range of expected fluctuations in cerebrospinal fluid pressure. CONCLUSIONS: These observations provide clinical confirmation of a defect in tissue overlying cavitary optic disc anomalies and imply interconnections between the vitreous cavity, subarachnoid space, and subretinal space. We theorize that intermittent pressure gradients resulting from normal variations in intracranial pressure play a critical role in the pathogenesis of retinopathy associated with cavitary disc anomalies.

Adult↗

Neovascular glaucoma after helium ion irradiation for uveal melanoma.

Neovascular glaucoma developed in 22 of 169 uveal melanoma patients treated with helium ion irradiation. Most patients had large melanomas; no eyes containing small melanomas developed anterior segment neovascularization. The mean onset of glaucoma was 14.1 months (range, 7-31 months). The incidence of anterior segment neovascularization increased with radiation dosage; there was an approximately three-fold increase at 80 GyE versus 60 GyE of helium ion radiation (23% vs. 8.5%) (P less than 0.05). Neovascular glaucoma occurred more commonly in larger tumors; the incidence was not affected by tumor location, presence of subretinal fluid, nor rate of tumor regression. Fifty-three percent of patients had some response with intraocular pressures of 21 mmHg or less to a combination of antiglaucoma treatments.

Anterior Eye Segment↗

Value of computed tomography for the diagnosis of a ruptured eye.

The diagnosis of scleral perforation of the globe following ocular trauma is often obvious on physical examination, but occult perforations occur frequently. In addition to locating intraorbital foreign bodies and associated facial bone fractures, computed tomography of the orbit can suggest an occult scleral rupture. Posterior collapse of the sclera causes flattening of the posterior contour of the globe, the "flat tire" sign. Other associated findings that are suggestive of scleral rupture are intraocular foreign body or gas, thickening of the sclera posteriorly, and a blood-vitreous fluid-fluid level.

Adolescent↗

Bilateral serous retinal detachments following organ transplantation.

PURPOSE: The authors report the physiopathogenetic features of bilateral serous neurosensory retinal detachments occurring in patients who have undergone organ transplantation. METHODS: The clinical and photographic findings of four patients who have undergone renal (3 cases) and liver (1 case) transplantation in whom bilateral serous retinal detachment developed early after surgery were reviewed. The patients were processed for clinical symptoms, visual acuity evaluation, slitlamp and fundus examinations, tonometry and fluorescein angiography. RESULTS: Ocular examination, in patients complaining of blurred vision and metamorphopsia, revealed loss of visual acuity, bullous serous neurosensory retinal detachment with retinal pigment epithelial detachments in fundus examination and areas of dye leakage in fluorescein angiography, despite tonometry and slitlamp examination were unremarkable. These alterations were spontaneously resolved with the normalization of renal function. CONCLUSION: The only common factor in each of the four patients resulted in alterations of the kidney function. This finding provides further evidence that renal failure may cause alterations in electrolytes extracellular distribution, leading to the formation of serous neurosensory retinal detachments.

Adult↗

The role of magnetic resonance imaging in vitreoretinal disorders.

Magnetic resonance imaging (MRI) is becoming a very useful diagnostic tool for the ophthalmologist. However, there is still some confusion among ophthalmologists and other clinicians regarding ordering and interpreting imaging studies. The role of MRI in the evaluation of vitreoretinal lesions is reviewed in this article by emphasizing the MR features of retinal tumors and simulating retinal or vitreal lesions. A special description of MR requirements for imaging the intraocular structures is provided as well as a review of the MR features of solid and fluid materials used in retinal surgery.

Eye Diseases↗

Influence of flunitrazepam on body functions.

The effects of intravenous flunitrazepam (Rohypnol, Roche) on various body functions were studied and the following conclusions were reached: it is a very potent sedative/hypnotic even in small doses, it may cause depression of spontaneous breathing, it does not give rise to raised cerebrospinal fluid or intra-ocular pressure, it does not adversely affect renal function, and it can be used quite safely in combination with fentanyl or pentazocine in anaesthetic practice.

Adult↗

The balloon-gas-procedure. Another move towards minimum surgery.

The balloon-gas-procedure eliminates drainage and mechanical vitrectomy; it can be done in topical or subconjunctival anesthesia. Continuous oculocompression is created with a parabulbar balloon inserted prior to surgery. This results in 'internal drainage' of aqueous from the vitreous. In a kind of 'fluid-gas-exchange' the balloon's contents are withdrawn and their volume simultaneously replaced with an intraocular injection of perfluorocarbon gas. The gas's subsequent expansion further compresses the vitreous. In this way a large intraocular gas bubble tamponade can be obtained with a single injection. If additional tamponading is required later on, the balloon volume can be incrased on the ward by an injection of saline over the balloon adapter. There are no late complications since both types of tamponade are only temporary. The balloon-gas-procedure represent another tool in the armamentarium of minimum surgery. With it a problem detachment can be treated by dividing it into 'small surgical steps.'

Adrenal Cortex Hormones↗

[Self tonometry during the German 1993 Spacelab D2 mission].

Microgravity during space missions leads to a fluid shift from the lower to the upper parts of the body that also affects the intraocular pressure. In the early phase after reaching microgravity there is an intraocular pressure peak. In order to analyse the potential health risks for astronauts, a self-tonometer was developed to examine the early phase of microgravity. During the German-Russian MIR mission the equipment was tested for the first time in space. As one result we found an initial pressure increase of 92% compared to the baseline data values. In order to obtain more detailed information on the intraocular pressure alterations in space, similar equipment was used during the 10-day German Spacelab D2 mission. Two German scientists and one American astronaut obtained self-tonometric pressure profiles on 6 mission days (44 pressure values determined out of 144 measurements). The initial peak values 15 min after entering microgravity revealed pressure increase of 114% compared to the baseline data (average pressure: right eye 10.0 mmHg, left eye 9.9 mmHg; peak values: right eye 22.6 mmHg, left eye 22.2 mmHg). Pressure values exceeding the baseline data by more than 50% were registered up to the 3rd mission day. As to circadian rhythm, there was no difference between inflight data and baseline data before and after the mission.

Adult↗

Intraocular oxygen tensions in normal and diseased eyes of farmed halibut.

We have previously documented ocular abnormalities in farmed halibut and reported that the production of gas-filled posterior segment cysts appears to be central in the pathogenesis of many, if not all of the signs in these eyes. In a number of fish, gas bubbles may be seen in the anterior chamber of the eye, especially after trauma or strenuous exertion associated with handling. A knowledge of the composition of this gas is important in understanding fully the mechanism of gas and cyst production. Here we report investigations into the composition of gas in the globes of normal fish, fish in which intraocular cysts have been documented previously by ultrasonography and fish where post-mortem examination demonstrated both gas- and fluid-filled choroidal cysts. High levels of oxygen were demonstrated in samples of aqueous from all fish but fish with affected eyes had a statistically significantly higher partial pressure of oxygen than did fish with normal eyes.

Animals↗

Experimental studies on viscofluids for intraocular surgery.

PURPOSE: To investigate the feasibility and efficacy of using diluted viscofluids during intraocular surgery. SETTING: Laboratory for Intraocular Microsurgery and Implants, Goldschleger Eye Research Institute, and the Sackler School of Medicine, Tel-Hashomer, Israel. METHODS: Diluted hyaluronic acid (0.06 to 0.12%) in balanced salt solutions were irrigated through the phacoemulsification machine or a separate irrigation line (i.e., anterior chamber maintainer). Irrigation was facilitated by increasing the atmospheric pressure in the bottle using compressed air. Experimental surgery was done in rabbit eyes. RESULTS: A viscous fluid could be irrigated at any practical rate by increasing the height of the bottle, increasing the atmospheric pressure within the bottle, or both. Experimental surgeries showed that viscofluids maintained intraocular pressure and anterior chamber volume, allowed safe intraocular manipulations, reduced turbulence in the anterior chamber, and probably provided tissue protection. CONCLUSION: Viscofluids irrigated using a high-pressure system combined the advantages of continuous irrigation of fluids and the protective qualities of viscoelastics in this rabbit eye study.

Animals↗

Outflow facility in acute experimental ciliochoroidal detachment.

Total outflow facility was measured by constant pressure perfusion in six cynomolgus monkey eyes with ciliochoroidal detachment and in fellow eyes following sham operation. Outflow facility in eyes with ciliochoroidal detachment was 0.22 +/- 0.04 microliter/min-1/mmHg-1 (P less than 0.05). Since the spontaneous intraocular pressure following acute ciliochoroidal detachment was lower than the normal episcleral venous pressure, it is concluded that the increase in outflow facility in eyes with ciliochoroidal detachment actually may be a measure of the rate of fluid flow across the sclera out of the suprachoroidal space.

Animals↗

Paradoxical hypotony after laser in situ keratomileusis.

We present a case of paradoxically low (0 to 2 mm Hg) intraocular pressure (IOP) measured by Goldmann applanation and Tono-Pen tonometry in an eye with corticosteroid-induced high IOP after laser in situ keratomileusis. The patient complained of blurred vision and ocular pain in both eyes. The eyes were firm by palpation, and the IOP measured by Schiotz indentation tonometry was 38 mm Hg. An interface fluid pocket was identified by slitlamp examination, and the corneal surface became steeper. These findings resolved after flap relifting, interface irrigation, and addition of antiglaucoma medications. We postulate that the paradoxically low reading by applanation tonometry was due to fluid accumulation within the flap-bed interface. The applanation tonometry reflected the interface fluid pocket pressure rather than the real high IOP. An exceedingly low IOP should be verified by palpation or by Shiotz indentation tonometry, and interface fluid should be identified.

Astigmatism↗

Sterile endophthalmitis in vitrectomised eyes due to suspected heat resistant endotoxins in the infusion fluid.

PURPOSE: To report on to the possibility of development of severe postoperative sterile endophthalmitis due to heat-resistant bacterial endotoxins in commercially available infusion fluids METHODS: A case study of 4 eyes that had previously undergone vitreoretinal surgery, which developed clinical endophthalmitis within 18 hours of surgery and two eyes that had vitreous surgery with intraocular gas and did not develop clinical endophthalmitis following intraocular surgery on three consecutive operative days RESULTS: The vitreous samples were sterile, both for bacteria and fungi. The only common supply in all cases was a new batch of Ringer's lactate infusion fluid. Though the Ringer's lactate solutions in the same batch were also sterile, the infusion fluids contained abnormally high levels of bacterial endotoxins detected by gel clot method. CONCLUSION: Commercially available infusion fluid may be sterile, yet contain endotoxins from killed bacteria. This could cause postoperative sterile endophthalmitis.

Adult↗

Visual field defect after pars plana vitrectomy.

OBJECTIVE: This study aimed to report the occurrence of visual field defects after pars plana vitrectomy (PPV) for the treatment of each of the following conditions: macular hole (MH), subretinal neovascular membrane (SRNVM), and epiretinal membrane proliferation (EMP). This study also aimed to speculate on the pathogenic mechanisms for the observed field defects. DESIGN: Noncomparative case series. PARTICIPANTS: The study included 48 subjects (50 eyes). Twenty-one of the 50 eyes had stage III MH, 13 eyes had SRNVM, and 16 eyes had EMP. TESTING: Goldmann kinetic perimetry was performed postoperatively. MAIN OUTCOME MEASURE: Visual field defects. RESULTS: Nine (18%) of the 50 eyes had visual field defects. Four (19%) of the 21 eyes with MH and 5 (38%) of the 13 eyes with SRNVM had visual field defects. Of the 16 patients who had epiretinal membrane peeling, none had a visual field defect. An air-fluid exchange had been performed in all patients found to have a postvitrectomy field defect. The difference in rate of visual field defects in eyes that had air-fluid exchange (EMP group) was statistically significant (P < 0.05, chi-square). No significant correlation was found between visual field defect and preoperative intraocular pressure, postoperative intraocular pressure, patient's age, and iatrogenic detachment of the vitreous cortex. The field defects identified were altitudinal (2 eyes), baring of the blind spot (1 eye), inferotemporal (3 eyes), inferonasal (2 eyes), and superonasal (1 eye). CONCLUSIONS: Central and peripheral visual field defects may occur after PPV for the treatment of MHs or SRNVMs. Air-fluid exchange procedure was the common denominator in all of the patients found to have visual field deficit. The etiology is likely to be trauma to the optic nerve region during the air-fluid exchange procedure.

Adult↗