A new type of contact lens for vitrectomy.

I designed a new type of contact lens for vitrectomy that consists of an outer scleral part and an inner rotatable cylindrical piece with a prismatic anterior surface.

Ocular perforation during retrobulbar and peribulbar injections.

BACKGROUND AND OBJECTIVE: To determine the ocular perforations during retrobulbar and peribulbar injections. PATIENTS AND METHODS: Twenty-five ocular perforations between 1976 and 1993 occurred after 13 retrobulbar and 12 peribulbar injections. Eighteen patients (72%) were women. Eighteen eyes were myopic (72%). Risk factors included high myopia in 11 cases (44%), use of Atkinson gaze in 21 cases (84%) and a sharp injection needle. RESULTS: Deep position of the posterior pole was common. Perforation signs comprised vitreous hemorrhage in 25 eyes (100%), subretinal hemorrhage in 19 eyes (76%), retinal breaks along the inferior vascular arcade in 19 eyes (76%), and retinal detachment in 14 eyes (56%). Proliferative vitreoretinopathy developed in 11 eyes (44%). CONCLUSION: Retinal detachment strongly correlated to poor visual outcome.

Limbal sub-Tenon's administration of retrobulbar anesthesia using a blunt irrigating cannula.

BACKGROUND AND OBJECTIVE: To eliminate sharp needles when administering local anesthesia to the eye in order to reduce serious complications caused by needle perforation. PATIENTS AND METHODS: After topical anesthesia, limbal conjunctival incision, and sub-Tenon's dissection, a retrobulbar irrigation of an equal mixture of bupivacaine (5 mg/ml) and lidocaine (20 mg/ml) was given using a blunt cannula. RESULTS: The technique was used in both vitreoretinal surgery (n = 70) and anterior segment surgery (n = 235) with good analgesic and akinetic effects. No serious adverse were noted. CONCLUSION: This proved to be a safe and efficient technique that abandoned the use of sharp needles.

Photocoagulation in diabetic retinopathy. A multicentre study in Sweden.

Two hundred and eleven patients with diabetic retinopathy were assigned to a multicentre prospective study on the effect of photocoagulation therapy. Twenty Swedish eye clinics took part in the trial. Good visual function and symmetrical diabetic retinopathy of the non-proliferative or proliferative type were required. No patients with advanced new vessels on the optic disc or widespread fibrous proliferations were included. Further criteria for inclusion were that at the time of entry into the study the patients would be in good general health, should have no other eye diseases and should be receiving no other treatment for diabetic retinopathy. One eye was randomly chosen for photocoagulation therapy. The patients were given mild treatment with the panretinal, focal or panretinal and focal techniques and in most cases the short-pulse, small-spot xenon arc or argon laser methods were used. The patients were examined before treatment, after 6 months and subsequently every year. All follow-ups included careful measurement of corrected visual acuity, tonometry, and evaluation of the optical media and fundus changes. A medical examination was performed every second year. Fundus photographs were taken at all examinations. The diabetic lesions were graded with the aid of a modified Airlie-House system. The classification of all diabetic lesions was checked by the author with the help of the fundus photographs. Visual acuity and morphological diabetic changes were analysed in the whole material and also in four subgroups, namely those with mild non-proliferative, moderate-severe non-proliferative, mild proliferative and moderate-severe proliferative retinopathy. This subgrouping was done with regard to the stage of retinopathy at entry into the trial. One hundred and eighty-five patients were followed up for 4 years and 138 for 5 years. Twenty patients died, most of them from diabetic complications. Forty-one control eyes were treated. The majority showed progression before treatment. Treated eyes had better average visual acuity and a lower rate of blindness than control eyes at late follow-up. The various stages of retinopathy differed greatly with respect to the visual outcome. Patients showing mild non-proliferative changes at the time of entry had good mean visual acuity and no eyes became blind during the follow-up period. Patients with moderate-severe non-proliferative changes had a better mean visual acuity in the treatment group at late follow-ups and more eyes became blind in the control group.(ABSTRACT TRUNCATED AT 400 WORDS)

Ophthalmomyiasis interna posterior.

Ophthalmomyiasis interna posterior (OIP) means infection of the posterior part of the eye with the larvae of flies. Few cases have been reported in which the larvae have been removed from the eye and the visual acuity preserved. We report four cases of OIP with living larva in the vitreous cavity. The larvae produced severe uveitis and were removed alive with vitrectomy and a procedure for removing foreign bodies. They were identified as first-stage reindeer warble fly larvae (Oedemagena tarandi). We also observed dead larva in the vitreous cavity of a patient who suffered severe uveitis in 1943, and this eye survived with normal visual acuity. Another patient had a blind eye enucleated and the remnants of a larva were found inside the eye. All patients live in Scandinavia.

Retinal detachment in aphakia.

In a prospective study five hundred consecutive cases of cataract operations were followed during ten years. Nine cases of retinal detachment were observed. In a retrospective study 77 cases with aphakic retinal detachment were studied according to type of cataract operation, interval between this operation and the onset of retinal detachment, refraction, area of detachment and results of treatment. About fifty percent of the cases of retinal detachment are observed during the first year after the cataract operation. At the first examination the detached area is usually larger in aphakic eyes than in phakic eyes. The anatomical and functional cure after detachment operation is probably less in aphakic than phakic eyes.

Healon GV in posterior segment surgery.

Healon, a viscoelastic preparation of Sodium hyaluronate, has been reported effective in posterior segment surgery for dissection of epiretinal membranes, i.e. proliferative diabetic retinopathy and macular pucker. A more viscous substance might be more effective for this kind of surgery. Therefore, a new Sodium hyaluronate preparation Healon GV with a ten times greater viscosity at rest than Healon, was tested in an open clinical study. Twenty-four patients of both sexes and not younger than 18 years were enrolled. The follow-up time was three months. The main indications for using Healon GV were: to separate membranes from the retina, to stop bleeding and to reposition a detached retina. 0.2-0.5 ml of Healon GV was injected through a 27 gauge bent cannula and at close of surgery irrigated out of the eye. Postoperatively the patients were monitored concerning intraocular pressure, vitreous clarity, anterior chamber flare and visual acuity. Healon GV was found to make the surgical procedure simpler and safer. No inflammatory reaction and no increase of IOP was observed.

Toxic ocular effects of two fibrinolytic drugs. An experimental electroretinographic study on albino rabbits.

The toxic effects on rabbit eyes of 2 intravitreally injected fibrinolytic substances at different concentrations were studied with repeated clinical observations and registrations of the DC ERG. The fellow, control eye of each animal was injected with saline. Urokinase (Ukidan, Serono) (13 rabbits) initially produced aqueous flare (64%), iris hyperaemia (36%) vitreous opacities (27%) and small retinal haemorrhages (18%). 2-3 months after the injection cataract (50%), vitreous opacities (25%) and retinal changes (13%) were observed. The highest dose (10 000 Ploug units) caused reduction of the ERG b-wave, as a sign of retinal toxicity. Tissue activator (D-44, Centre d'immunologie et de biologie Pierre Fabre) (10 rabbits) produced marked aqueous flare (initially 100%, after 2 weeks 50%) and pronounced, persistent vitreous opacities (25% after 2-3 months). At the late stage corneal blood vessels (38%) and cataract (38%) were also found, but only in eyes injected with the highest dose (1000 units), which was retinotoxic as judged by the ERG (reduced b- and c-waves).

Retinal detachment. A study of a population-based patient material in Sweden 1971-1981. I. Epidemiology.

A population-based series of retinal detachments (RD) collected during a 10-year period (538 patients, 590 'cases', i.e. diseased eyes including new RD after 6 months in the same eye) is reported. The annual incidence was 10.6 per 100,000 population. Bilaterality was observed in 11.2%. In this material preponderance of the right eye was found. In non-traumatic RD there was a small sex difference, with a higher incidence among females. Older persons were at high risk of sustaining RD, as were myopes. In myopic males the risk increased with the degree of myopia and with increasing age. In myopic females the greatest risk was found in the age group 30-59 years. Myopic eyes are probably also more vulnerable to traumatic RD. Lattice degeneration was more common in middle-aged than in older patients and was also more common in myopic eyes than in eyes with other phakic RD. High myopia (greater than -5D) was more frequent in patients with lattice degeneration than in those without. Aphakia was found to be an important predisposing factor for RD. A classification taking into account the above-mentioned factors is proposed.

Retinal detachment. A study of a population-based patient material in Sweden 1971-1981. II. Pre-operative findings.

In a population-based material of patients with retinal detachment (RD), the pre-operative findings in different subgroups were studied. In traumatic cases flap tears and round holes were found in at least as high a frequency as oral dialysis, or even higher. In aphakic cases subtotal or total RD was often observed on admission for surgery. A high proportion of aphakic eyes without lattice degeneration exhibited no breaks. RD in myopic eyes was usually large, and round holes were frequently found. Full-thickness fixed retinal folds were more seldom seen pre-operatively en myopic than in non-myopic eyes. Lattice degeneration was usually observed in myopic RD patients of ages less than 30 years, but mainly in hyperopic or emmetropic eyes in patients over 60. In RD with lattice, multiple breaks were frequently found. A comparatively large group of RD cases without lattice were non-traumatic, phakic and non-myopic (40%). Most of these patients were 60 years and older. Flap tears were often seen, and the detachment was seldom large in this group.

Primary scleral atrophy and retinal detachment.

In a retrospective study 27 patients with retinal detachment had an advanced primary scleral atrophy, needing treatment with a scleral graft. Among these 27 patients none was younger than 47. There was s good correlation between the location of the atrophic sclera and the retinal tears. Many of these eyes had an oblique astigmatism. Lattice degeneration was found to be rare. A history of retinal detachment was common in the fellow eye. The scleral grafts were well accepted by the eyes.

Vitreous surgery in patients with primary neuropathic amyloidosis.

Pars plana vitrectomy was performed in 9 patients from the north of Sweden because of amyloid deposits of the vitreous. Operative technique and post-operative results are presented.

Relation of vitreous amyloidosis to prealbumin.

Amyloid fibrils were isolated from the vitreous of 9 patients with familial amyloidosis. The material of all patients contained proteins reacting in double immunodiffusion with an antiserum against an amyloid protein which previously has been shown to be prealbumin-related. Two out of five tested vitreous amyloid materials also showed a reaction of identity with antihuman prealbumin. It was shown by electrophoresis that the amyloid subunit consisted of two low molecular weight components, one in size similar to prealbumin and one slightly smaller, which appears to be a degradation product of prealbumin. The proportion between the two components seems to vary. It is concluded that besides the presence of an abnormal prealbumin, other factors are of importance for the formation of amyloid precipitates in the vitreous.

Hypertensive retinal vascular changes: relationship to left ventricular hypertrophy and arteriolar changes before and after treatment.

Eye-ground-photos were taken in twenty-eight previously untreated men with mild to moderate essential hypertension. The same eye was evaluated before and after 26 weeks of double-blind treatment with Enalapril or Hydrochlorothiazide. The vascular changes were assessed by using a more elaborate and refined grading than the Keith-Wagener-Barker scale. All photos were examined by the same observer without knowledge of blood pressure, type of treatment or the order in which the photos had been taken. There were significant positive correlations between the vascular alterations in the retina in the untreated state and left ventricular wall thickness (echocardiography), minimal vascular resistance in the calf (plethysmography) and blood pressure respectively. Treatment with Enalapril decreased the reflection of the retinal arterial wall significantly and reduced the narrowing of arteries and arterio-venous crossing phenomena non-significantly. Hydrochlorothiazide did not affect any of the retinal vascular changes. It can be concluded that this relatively simple technique of evaluating eye-ground-photos with a new grading scale, when used in non-malignant hypertension, gives a useful assessment of the degree of hypertensive target organ damage in the retina as well as in other important target organs, i.e. the heart and vascular beds. In addition, Enalapril positively affects hypertensive retinopathy in contrast to Hydrochlorothiazide, reflecting what happens to structural cardiovascular changes in the rest of the body.

A new technique of treating rhegmatogenous retinal detachment using the Q-switched Nd:YAG laser.

In eyes with retinal detachment and a horseshoe break, vitreous traction on the retina has been relieved by severing the flap of the break with the aid of the Q-switched Nd:YAG laser. The retina often flattens in eyes with shallow retinal detachment after this treatment; the breaks then can be sealed off with argon laser. In cases of retinal detachment treated with expanding gas, fewer recurrences were observed when vitreous traction had been relieved by Nd:YAG laser treatment.