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S M Meyers

Publications and source records attributed to S M Meyers.

At least 19 recordsLinked to original sources
PubMed1994

A twin study on age-related macular degeneration.

A prospective twin study on age-related macular degeneration (AMD) recruited 83 monozygotic pairs, 28 dizygotic pairs, and one triplet set from 1986 through 1993. Zygosity was determined by genetic testing of red cell markers, HLA antigens, or specific DNA loci. There were no twin pairs in which I collected data on only one twin. To decrease ascertainment bias, after 1991 the recruitment notice did not mention AMD, and I did not ask about a history of eye disease before the eye examination. Because of this, twin pairs recruited from 1986 through 1991 were statistically analyzed separately from those after January 1, 1992. From 1986 through 1991, 23 twin pairs were recruited; 11 monozygotic and 2 dizygotic pairs had nonAMD retinal changes or no retinal abnormalities, 9 monozygotic pairs with AMD were all concordant, and 1 dizygotic pair was discordant for basal laminar drusen. The concordance rate of AMD did not differ significantly between monozygotic and dizygotic twin pairs (P = .10) for 1986 through 1991. In 1992 and 1993, 88 twin pairs and one triplet set were recruited; 49 monozygotic and 19 dizygotic pairs had nonAMD retinal changes or no retinal abnormalities, 14 monozygotic pairs with AMD were all concordant, and 2 of 7 dizygotic pairs were concordant for AMD. The nonidentical triplets (1 with and 2 without AMD) were categorized as one of the discordant dizygotic pairs in the statistical evaluation. In nontwin age-matched (within 2 or 5 years of age) or age- and sex-matched sibling pairs the concordance rate of AMD ranged from 16% to 25%. The concordance rate of AMD was significantly higher in monozygotic than in dizygotic twins (P = .001) for 1992 and 1993. The concordance rate was higher for monozygotic twin pairs recruited in 1992 and 1993 than in any of the four subsets of nontwin age-method or age- and sex-matched sibling pairs (P < .0001). Overall, from 1986 through 1993, 23 of 23 monozygotic and 2 of 8 dizygotic twin pairs were concordant for AMD; this included the one dizygotic pair which was discordant for basal laminar drusen. The data of this study strongly suggest a genetic predisposition to AMD.

Adult↗
PubMed1992

Ocular findings associated with neurofibromatosis type II.

BACKGROUND: Neurofibromatosis has been recently acknowledged as consisting of a number of different diseases. Neurofibromatosis (NF) type I and NF type II are the most clearly defined. Type II is characterized by bilateral acoustic neuromas and is rare (its incidence is 1/50,000). The previously reported ocular associations of NF type II are posterior subcapsular cataracts, Lisch nodules, and combined hamartomata of the retinal pigment epithelium and retina. In this study, the authors attempt to define further the ocular manifestations of NF type II. METHODS: The authors prospectively examined 9 patients who met the diagnostic criteria for NF type II (age, 18 to 38 years; mean, 25 years). RESULTS: Seven of nine patients had epiretinal membranes in the posterior pole. None of these epiretinal membranes were visually significant. In addition, five patients had central posterior cortical cataracts and five had peripheral wedge-shaped cortical cataracts. CONCLUSION: The presence of epiretinal membranes in young patients may represent another clinical finding associated with NF type II. Epiretinal membranes, central posterior cataracts, peripheral cortical cataracts, or combined hamartoma of the retinal epithelium and retina in young patients should alert the ophthalmologist to include NF type II in the differential diagnosis in patients with stigmata of NF type II.

Adolescent↗
PubMed1992

Variation of perfluoropropane disappearance after vitrectomy.

In complex cases of retinal detachment, perfluoropropane (C3F8) is frequently used after vitrectomy for tamponade of retinal breaks. Results of previous studies of C3F8 disappearance using 10% C3F8 after vitrectomy in human eyes have differed significantly. A wide variation in the decay rate and half life of C3F8 after vitrectomy was observed in eyes that had similar clinical settings and received the same C3F8 concentration (15%, 20%, or 25%). This occurred even in those eyes where there was no change in the geometric contour of the eye after a repeat vitrectomy.

Eye↗
PubMed1992

Comparative response of nestling European starlings and red-winged blackbirds to an oral administration of either dimethoate or chlorpyrifos.

Red-winged blackbird (Agelaius phoeniceus; blackbird) and European starling (Sturnus vulgaris; starling) nestlings were dosed with either 2.0 mg/kg body mass chlorpyrifos, 50.0 mg/kg body mass dimethoate, or a propylene glycol carrier in situ. Four growth measurements (body mass, culmen, tarsus, wing) were recorded from nestlings to determine if these organophosphorus compounds caused perturbations in development at sublethal concentrations. Blackbird nestlings were more sensitive to chlorpyrifos than starling nestlings were more sensitive to dimethoate than blackbird nestlings. This was in contrast to reported adult LD50 values where the reverse was true. Blackbird nestlings were more tolerant of a substantially higher concentration of dimethoate than the adult LD50. The sensitivity of starling nestlings to dimethoate was similar to adults. In contrast, juveniles of both species were more sensitive to chlorpyrifos than adults. After the initial 24 hr, surviving nestlings dosed with either chemical recovered and continued their development. Exposure to dimethoate caused significant depression in starling body mass during the initial 24 hr period. Survivors obtain body mass equal to controls within 48 hr post dosing. The research presented here demonstrates that the simple supposition that passerine nestlings are typically more sensitive to toxins than adults does not always hold true. It also indicates that sensitivity relationships among adults do not necessarily apply to their nestlings.

Administration, Oral↗
PubMed1991

Acute multifocal inner retinitis.

Two patients developed acute changes in vision two to four weeks after a febrile illness. On ophthalmic examination, each patient had bilateral vitreitis without anterior segment inflammation and multiple, bilateral, round, yellow-white inner retinal lesions that were located in the posterior pole and midperiphery. Laboratory tests did not contribute to a diagnosis. Symptomatic visual loss was caused by neuroretinitis and serous retinal detachment in one patient and by an occluded branch retinal artery in the other. The multifocal retinal lesions resolved gradually without treatment over several months with minimal or no residual retinal changes. Acute multifocal inner retinal lesions may be associated with a preceding nonspecific viral illness and may cause a sudden change in vision if associated with neuroretinitis, serous retinal detachment, or retinal vessel occlusion. We have termed this constellation of ophthalmic findings acute multifocal inner retinitis.

Acute Disease↗
PubMed1991

Management of intraretinal metallic foreign bodies without retinopexy in the absence of retinal detachment.

In the management of intraocular metallic foreign bodies impacting or embedded in the posterior retina but without retinal detachment, retinopexy can be difficult or dangerous because of surrounding retinal, subretinal, or choroidal hemorrhage, or the proximity of the foreign body to the optic disc and macula. The authors prospectively managed five such cases by pars plana vitrectomy and foreign body removal without intraoperative or postoperative retinopexy. Fluid gas exchange was performed in only one case. No attempt was made to create a posterior vitreous detachment in any of the cases. After follow-up, ranging between 8 and 35 months, all cases had attached retinas and chorioretinal adhesion around the foreign body site. None of the cases had preretinal macular fibrosis. Four of the five cases had a best corrected visual acuity of 20/20 or better. The other, an aphakic 3-year-old patient, was amblyopic. Spontaneous chorioretinal adhesion appears to obviate the need for retinopexy in these selected cases. The avoidance of retinopexy and fluid gas exchange may decrease the risk of retinal detachment and preretinal macular fibrosis.

Adolescent↗
PubMed1991

Retinal detachment as a complication of retrobulbar anesthesia.

The authors report an unusual case of retinal detachment after cataract surgery in a 48-year-old man in which it appeared that the retrobulbar needle passed through the sclera and tracked beneath the retina before perforating the retina superior to the disc. The cause of the detachment was not clearly defined until a depigmented line was observed after reattachment of the retina.

Anesthesia, Local↗
PubMed1990

Reoperations and visual results after failed pneumatic retinopexy.

A single pneumatic retinopexy (PR) procedure failed to achieve permanent retinal reattachment in 23 (23%) of 101 cases of simple primary retinal detachment (RD). In 12 (16%) of 76 cases that were phakic or had an intact posterior capsule, a single PR failed compared with 11 (44%) of 25 cases without an intact posterior capsule. A total of 27 reoperations including eight repeat PRs (5 of which were successful) was required to achieve permanent retinal reattachment. Comparison of the final visual acuity and change from preoperative to final visual acuity between the initially failed and the successful cases demonstrated that initial failure of PR does not adversely affect the visual outcome. In all cases, the retina remained reattached at latest follow-up.

Analysis of Variance↗
PubMed1990

Pathways to psychotropic drugs. Understanding the basis of gender differences.

Earlier studies have established substantial gender differences in the likelihood of obtaining a psychotropic drug prescription, and a correlation, especially among women, with such family characteristics as family responsibilities, marital separation, divorce or widowhood, and the presence of family stressors such as an ill spouse. However, the pathways to psychotropic drug use are not clearly understood. Data from the National Medical Care Expenditure Survey show that gender differences in obtaining a psychotropic drug can be accounted for by the greater likelihood of women to perceive illness, particularly mental illness and musculoskeletal conditions, diagnostic conditions that together account for roughly half of all psychotropic drug prescriptions. In relation to family responsibilities, employment significantly decreases the likelihood of a psychotropic drug prescription for both men and women. The greater likelihood of divorced, separated, or widowed women to obtain psychotropic drugs can be explained by their greater likelihood of episodes of illness, particularly those involving mental illness, and by their greater number of physician visits. The presence of all ill spouse is associated with psychotropic drug use only indirectly by increasing the likelihood of Medicaid coverage. Thus, differences between men and women in the likelihood of obtaining prescriptions for psychotropic drugs do not appear to result from different physician-patient interactions or from gender-determined treatment norms by physicians.

Adult↗
PubMed1990

Chronic macular detachment following pneumatic retinopexy.

In a consecutive series of 73 retinal detachments managed with pneumatic retinopexy, three (4.1%) of 73 eyes sustained chronic detachment of the posterior retina involving the macula even though all retinal breaks were closed. This shallow subretinal fluid persisted for 12 to 21 months but reabsorbed spontaneously. Two cases presented with a detached macula, one of which had pre-existing macular degeneration. The other case presented with an attached macula but it became detached immediately after pneumatic retinopexy. The visual acuities in the two patients who did not have macular pathology before the development of retinal detachment were 20/50 and 20/40 even with persistent subretinal fluid under the macula. In both cases the visual acuity improved to 20/30 after resolution of the subretinal fluid. Patients with a longstanding component to the retinal detachment and small retinal breaks may be at risk of developing chronic macular detachment following pneumatic retinopexy. Pockets of subretinal fluid can persist following scleral buckling, with or without drainage of subretinal fluid. However, it is unknown whether scleral buckling has a lower incidence of this complication than pneumatic retinopexy.

Aged↗
PubMed1989

The management of retinal detachment complicating degenerative retinoschisis.

We repaired six retinal detachments complicating degenerative retinoschisis by using simultaneous external subretinal fluid drainage and intraocular gas injection without a scleral buckle or vitrectomy. The outer wall breaks were 30 to 135 degrees in size, and in three cases, extended close to the arcade vessels. We achieved retinal reattachment and collapse of the schisis cavity at surgery in all six cases. In one case, the retina redetached postoperatively, but it was repaired with a scleral buckle and gas injection. This technique simplified the management of retinal detachments complicating degenerative retinoschisis, particularly those with large or posterior outer-layer breaks.

Adult↗
PubMed1988

Repeated fluid-gas exchange for hypotony after vitreoretinal surgery for proliferative vitreoretinopathy.

Three patients with prolonged hypotony after vitreoretinal surgery for proliferative vitreoretinopathy were treated with repeated fluid-gas exchanges to maintain intraocular pressure and prevent the development of phthisis bulbi. We performed fluid-gas exchanges solely to treat the hypotony beyond the period when tamponade of retinal breaks was required, and without specific positioning of the bubble. In these patients, the intraocular pressure eventually returned to normal and useful vision was retained.

Adult↗
PubMed1988

Monozygotic twins with age-related macular degeneration.

This clinical study, to the best of our knowledge, is the first report of severe age-related macular degeneration in both identical twins, documented as monozygotic by genetic testing. This suggests that genetic factors may be of primary importance in certain cases of age-related macular degeneration.

Age Factors↗
PubMed1988

Comparison of pneumatic retinopexy with alternative surgical techniques.

To determine the efficacy of pneumatic retinopexy, the authors conducted a retrospective study of 56 cases of uncomplicated retinal detachments (RDs) treated with this technique (follow-up, 6-18 months). These were compared with 28 similar cases treated with a Lincoff balloon and 78 similar cases treated with a scleral buckle. The long-term success rates for these three groups were 71, 64, and 96%, with the incidence of new breaks being 20, 18, and 1.3% respectively. In aphakic or pseudophakic patients with an absent or ruptured posterior capsule, the success rate for pneumatic retinopexy was only 43%. In phakic and aphakic patients with an intact posterior capsule, the success rate for pneumatic retinopexy improved to 81%. These data suggest that this technique is less effective in aphakic or pseudophakic patients with an absent or ruptured posterior capsule and that careful follow-up to detect new breaks is necessary in all cases. A prospective randomized study is needed to verify these data.

Air↗