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C L Trempe

Publications and source records attributed to C L Trempe.

At least 37 records · Page 2Linked to original sources
PubMed1995

Relationship between premacular cortical vitreous defects and idiopathic premacular fibrosis.

PURPOSE: To investigate the relationship between the defect in the premacular cortical vitreous detached from the retina and the development of idiopathic premacular fibrosis. METHODS: One hundred six consecutive patients (106 eyes) with posterior vitreous detachment but no other ocular disorders were prospectively studied. All follow-up periods were longer than 6 months. The vitreous condition was studied using an aspherical, +58.6-diopter preset lens with a slit-lamp. RESULTS: The detached premacular cortical vitreous was a continuous, unbroken sheet in 93 (88%) of the 106 eyes; in 13 (12%) eyes, the detached premacular cortical vitreous had an oval or round defect ranging from 4 to 7 disc diameters over the macula. At the study's conclusion, 36 (34%) of the 106 eyes had idiopathic premacular fibrosis; 70 (66%) eyes did not. The defect in the detached premacular vitreous was observed in 9 (25%) of the 36 eyes that eventually developed idiopathic premacular fibrosis and in 4 (6%) of the 70 eyes that did not undergo such development. The incidence of the defect in the detached premacular cortical vitreous was significantly higher in eyes with idiopathic premacular fibrosis than in eyes without (P = 0.011). Nine (69%) of thirteen eyes with the defect in the detached premacular cortical vitreous developed premacular fibrosis, whereas only 25% of eyes without the defect developed it. Twenty-seven (75%) of thirty-six eyes with premacular fibrosis did not have a defect in the detached premacular cortical vitreous. CONCLUSIONS: The defect in the detached premacular cortical vitreous probably occurs because the premacular cortical vitreous remains attached to the internal limiting lamina when a posterior vitreous detachment develops. The vitreous that remains attached to the macula may be related to the development of idiopathic premacular fibrosis.

Adult↗
PubMed1995

Natural outcomes of stage 1, 2, 3, and 4 idiopathic macular holes.

AIMS: A study was carried out to ascertain the natural outcome of each stage of idiopathic macular hole. METHODS: One hundred and fifty four eyes with different stages of idiopathic macular holes were retrospectively studied: stage 1 (40 eyes), 2 (25 eyes), 3 (58 eyes), and 4 (31 eyes). RESULTS: Of 27 of 40 eyes with a stage 1 lesion with posterior vitreous attachment to the macula initially, nine (33%) eyes developed a full thickness macular hole. No stage 1 lesions with posterior vitreous separation from the macula initially progressed to full thickness holes. Twenty one (84%) of 25 eyes with a stage 2 lesion, 32 (55%) of 58 eyes with a stage 3 lesion, and five (16%) of 31 eyes with a stage 4 lesion underwent macular hole enlargement during the median follow up period of 3 years. Visual acuity decreased two or more lines of Snellen equivalent during the follow up period in 12 (30%) eyes with a stage 1 lesion, 17 (68%) eyes with a stage 2 lesion, 17 (29%) eyes with a stage 3 lesion, and four (13%) eyes with a stage 4 lesion. The percentage was significantly higher in eyes with stage 2 lesions than the other stages (p < 0.01). CONCLUSION: The results suggest that the different stages of idiopathic macular holes have different natural outcomes, and the management depends on the stage at presentation.

Age Distribution↗
PubMed1995

[Natural outcome of idiopathic macular hole].

To ascertain the natural outcome of idiopathic macular holes, we studied 186 eyes with the disorder: stages 1 (48 eyes), 2 (30 eyes), 3 (71 eyes), and 4 (37 eyes), which were followed for over twelve months. In 11 (23%) eyes with stage 1 lesions full-thickness macular hole developed during the follow-up period, and in 12 (25%) eyes visual acuity decreased two or more Snellen lines. Twenty-five (83%) and 21 (70%) eyes with stage 2 lesions, 39 (55%) and 22 (31%) eyes with stage 3 lesions, and 7 (19%) and 5 (14%) eyes with stage 4 lesions had enlarged macular holes and decreased visual acuity during the follow-up, respectively. The present results suggest that different stages of macular holes have different natural outcomes and the treatment should be based on their stages.

Aged↗
PubMed1995

[Observing idiopathic macular break by scanning laser ophthalmoscope vitreous videography].

We used vitreous videography in conjunction with the scanning laser ophthalmoscope (SLO) to evaluate the pathogenesis of idiopathic macular breaks. The fundamental aspect of this method is videographic documentation of the mobile posterior vitreous and an operculum. The high reflectivity from the vitreous gel using the SLO clearly showed the mobility of the operculum and the posterior vitreous in the idiopathic macular breaks. In some cases without posterior vitreous detachment, the operculum initially was suspended superior to the macular break and anterior to the retinal surface. Upon ocular movement, the operculum moved down smoothly in front of the macular break. The findings of these vitreous videographs using the SLO suggest that anteriorly oriented vitreous traction is one cause of idiopathic macular breaks.

Aged↗
PubMed1994

Relationship between floaters, light flashes, or both, and complications of posterior vitreous detachment.

We examined biomicroscopically the vitreous and retinal conditions of 902 consecutive symptomatic eyes (785 patients) to ascertain the relationship between floaters, light flashes, or both, and complications of posterior vitreous detachment. Of 785 patients, 785 symptomatic eyes were divided as follows: group 1, 342 eyes with floaters alone; group 2, 240 eyes with floaters and light flashes; and group 3, 203 eyes with light flashes alone. We also studied 636 asymptomatic fellow eyes. The prevalence of posterior vitreous detachment was significantly higher in groups 1 (138 of 342, 40%), 2 (214 of 240, 89%), and 3 (137 of 203, 67%) than in the asymptomatic eyes (127 of 636, 20%), in group 2 than in groups 1 and 3, and in group 3 than in group 1 (P = .01). The prevalence of retinal breaks in eyes with posterior vitreous detachment was 5% (seven of 138), 13% (27 of 214), 12% (16 of 137), and 4% (five of 127) in groups 1, 2, 3, and the asymptomatic eyes, respectively; the prevalence was significantly higher in groups 2 and 3 than in asymptomatic eyes (P = .02 and P = .04) and group 1 (P = .04 and P = .05). The prevalence of vitreous hemorrhage in eyes with retinal breaks was 71% (five of seven), 70% (19 of 27), and 6% (one of 16) in groups 1, 2, and 3, respectively. Of 117 patients with bilateral symptoms, 105 (90%) had the same symptoms and 104 (89%) had the same vitreoretinal relationship bilaterally.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Vitreomacular observations. I. Vitreomacular adhesion and hole in the premacular hyaloid.

PURPOSE: Variations in vitreomacular adhesions and the significance of a hole in the premacular hyaloid membrane were studied clinically to better understand vitreomacular pathology. METHODS: With an El-Bayadi-Kajiura aspheric preset lens, the authors used a vitreous examination technique on 96 eyes, which were divided into three groups. Findings were recorded photographically. RESULTS: Group 1 (25 eyes, 26%) included eyes with a partial posterior vitreous detachment and a residual vitreomacular attachment, but no hole in the premacular hyaloid. All eyes in this group, except one, showed another complication. Diabetic retinopathy and retinal vein occlusion were the most frequent problems noted. Premacular fibrosis, often present in these eyes, may have been precipitated by a vascular complication in the retina. In groups 2 and 3 (71 eyes, 74%), a hole was seen in the premacular hyaloid. Group 2 (46 eyes, 48%) comprised eyes showing a partial posterior vitreous detachment with a strand of vitreous that extruded through the hole in the posterior hyaloid and adhered to the macula. In group 3 (25 eyes, 26%), the hole in the premacular hyaloid was accompanied by a total posterior vitrous detachment. The most common complication noted in eyes in groups 2 and 3 was premacular fibrosis (34 of 71 eyes, 47.9%). The persistence of a residual vitreous attachment to the macula was accompanied by a significantly greater frequency of visual acuity equal to or worse than 20/200. CONCLUSIONS: Variations in vitreomacular pathology seem to result from differences in the strength of the vitreomacular adhesion and in the process of vitreous liquefaction and shrinkage. In patients with a hole in the premacular hyaloid membrane, the vitreomacular attachment is stronger than the vitreous attachment to other parts of the retina. The latter feature may cause visual acuity deterioration. When there is a hole in the premacular hyaloid membrane, the presence or absence of a vitreomacular adhesion may affect the prognosis for macular function.

Adult↗
PubMed1994

The vitreous in retinal arterial occlusions.

PURPOSE: To investigate whether retinal arterial occlusion induces posterior vitreous detachment (PVD). METHODS: Vitreous condition was studied retrospectively and examined on biomicroscopy in 52 eyes with retinal arterial occlusion; 50 fellow eyes served as controls. RESULTS: Of 52 eyes with retinal arterial occlusion 27 (52%) had PVD; 25 (50%) of the 50 control eyes had PVD. There was no significant difference between the two groups in prevalence of PVD. Of the 41 patients observed for more than 1 year, PVD developed in 2 (5%) patients from each group. CONCLUSION: Our findings strongly suggest that retinal arterial occlusion does not influence the development of PVD clinically.

Adult↗
PubMed1994

Image enhancement for the visually impaired: the effects of enhancement on face recognition.

Image enhancement has been shown to improve face recognition by visually impaired observers. We conducted three experiments in an effort to refine our understanding of the parameters leading to this effect. In experiment 1 we found that the band of spatial frequencies between 4 and 8 cycles/face is critical for face recognition. In experiment 2 we found that enhancement of these frequencies and the resulting image distortion actually reduced recognition performance for normal observers. Since the degradation of performance by low vision is larger than the effect of distortion, the enhancement that reduces performance for normal observers may still be beneficial for the visually impaired observer. Experiment 3 found that patients tend to prefer images enhanced at frequencies higher than the critical frequencies found in experiment 1. Such individually selected enhancement did not improve recognition in comparison with uniformly applied enhancement. The lack of an enhancement effect may be due to the small variability in enhancement frequencies selected by our subject population.

Adult↗
PubMed1994

Cross-linking of dermal collagen induced by singlet oxygen.

Changes were studied in dermal collagen induced by singlet oxygen, which was generated by a bilirubin-photosensitized reaction. An increase in the ratio of high-molecular-weight components (beta- and r-components) against the alpha-chain of collagen after irradiation manifested in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Sodium azide, a singlet oxygen quencher, inhibits the alteration of the molecular size by the photochemical reaction. These data suggest that chronic sunlight irradiation may contribute to cross-links of dermal collagen.

Animals↗
PubMed1993

Risk of decreased visual acuity in full-thickness idiopathic macular holes.

We studied 169 eyes of 149 patients with a full-thickness idiopathic macular hole to ascertain the risk factors of enlargement of the hole or the surrounding retinal detachment and subsequent decreased visual acuity. Eyes were divided as follows: group A, 48 eyes with no posterior vitreous detachment and a hole 400 microns or smaller; group B, 77 eyes with no posterior vitreous detachment and a hole 400 microns or larger; group C, 13 eyes with posterior vitreous detachment and a hole 400 microns or smaller; group D, 31 eyes with posterior vitreous detachment and a hole 400 microns or larger. In group A, the macular hole enlarged in 37 eyes (77%); the retinal detachment enlarged in 35 eyes (73%); and visual acuity decreased by two or more Snellen lines in 28 eyes (58%). These percentages were significantly higher than those in group B (P = .01, P = .01, and P = .01, respectively), group C (P = .02, P = .01, and P = .01, respectively), and group D (P = .01, P = .05, and P = .01, respectively). Eyes without posterior vitreous detachment with a full-thickness idiopathic macular hole 400 microns or smaller may have a greater risk of an enlarged macular hole, surrounding retinal detachment, and subsequent visual loss.

Aged↗
PubMed1993

Role of the vitreous in the prognosis of peripheral uveitis.

We studied 116 eyes with peripheral uveitis (mean follow-up, 5.0 years) to ascertain the effect of the vitreous on prognosis. At the initial examination, the prevalence of partial posterior vitreous detachment was significantly higher in eyes with macular edema (27%) than in those without (7%, P = .01). During follow-up, the prevalence of no posterior vitreous detachment initially was significantly higher in eyes that developed macular edema (78%) than in those that did not (22%, P = .01). The prevalence of no or partial posterior vitreous detachment was also significantly higher in eyes with decreased visual acuity of three or more Snellen lines (57% and 38%, respectively) compared with those with visual acuity decreases of two Snellen lines or less (21% and 11%; P = .02 and P = .01, respectively). Eyes with peripheral uveitis with vitreous adhesion may have a less favorable prognosis compared with those with complete posterior vitreous detachment.

Adolescent↗
PubMed1993

Effect of the vitreous on the prognosis of full-thickness idiopathic macular hole.

We studied 112 eyes with full-thickness idiopathic macular holes (mean follow-up period, 5.7 years) to ascertain the effect of the vitreous on prognosis. Eyes were divided as follows: group 1, 58 eyes with no posterior vitreous detachment; group 2, 25 eyes with no posterior vitreous detachment initially and development of complete posterior vitreous detachment during follow-up; and group 3, 29 eyes with complete posterior vitreous detachment. In group 1, the macular hole enlarged in 37 eyes (64%), and the surrounding retinal detachment enlarged in 29 (50%); visual acuity decreased in 20 eyes (34%) by two or more Snellen lines. These percentages were significantly higher than in group 3 (14%, 10%, and 10%; P = .01, P = .01, and P = .03, respectively). Eyes with a full-thickness macular hole with no posterior vitreous detachment may have a greater risk of enlargement of the macular hole and surrounding retinal detachment, and thus a worse prognosis than eyes with posterior vitreous detachment.

Aged↗
PubMed1993

Vitreous findings in cases of optic nerve pits and serous macular detachment.

We examined biomicroscopically the relationship between the optic nerve and the vitreous in 17 eyes of 16 consecutive patients with pits of the optic nerve that demonstrated an associated serous detachment of the macula. The posterior vitreous was attached in 15 eyes (88%); the posterior vitreous was partially detached with a vitreous strand terminating at the optic pit in two eyes (12%). Of the 15 eyes without posterior vitreous detachment, 11 (73%) had an anomalous Cloquet's canal that was markedly condensed and terminated at the margin of the pit. During ocular movement, we observed a back-and-forth movement of the anomalous Cloquet's canal and a pulsating translucent membrane that covered the pit. Our findings suggest that the intravitreal traction on the optic pit by the anomalous Cloquet's canal may have a role in the development of macular detachment.

Adolescent↗
PubMed1993

Vitreous photography with a wide-angle funduscopic lens.

A wide-angle funduscopic lens was used to take slit-lamp photographs of the posterior vitreous. The lens was then evaluated for its optics, magnification, field of view, and photographic usefulness and compared with the photographs taken using double aspheric preset lenses. The advantages of the wide-angle funduscopic lens were its wider field of view and ability to photograph the vitreous in the presence of a small pupil and cataract. The drawbacks were the darker image, low magnification, and artifactitious light reflection from the lens. The slit-lamp photographs using the wide-angle funduscopic lens were very useful in some complicated cases.

Eye Diseases↗
PubMed1993

Biomicroscopic findings of posterior vitreoschisis.

The clinical entity of posterior vitreoschisis, splitting of the posterior cortical vitreous, is not well known. We confirmed its presence biomicroscopically in cases with posterior vitreous detachment and found it mostly associated with retinal vascular diseases, usually manifesting as two dense vitreous membranes with defects. When posterior vitreoschisis develops in an otherwise normal eye, it may not manifest as two membranes, but can form a crescent-shaped, optically empty space in the posterior vitreous cavity. Because its management is different, posterior vitreoschisis should be differentiated from other, apparently similar, conditions, especially posterior vitreous detachment.

Adult↗