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D C Musch

Publications and source records attributed to D C Musch.

At least 37 records · Page 2Linked to original sources
PubMed1996

Evaluation of levator muscle integrity in ptosis with levator force measurement.

PURPOSE: To determine the efficacy of the force the levator muscle can generate as a diagnostic tool for ascertaining the cause of ptosis. METHODS: A total of 187 patients with ptosis were evaluated clinically, their levator force was measured, and each ptotic eyelid subsequently had surgical correction. At each step, patients received a diagnosis of congenital or acquired (history- dependent) aponeurotic, myogenic, neurogenic, or mechanical ptosis. To measure the levator force, a clamp placed on the upper eyelid lashes was attached to a force transducer. The maximum force generated on upgaze was recorded as the levator force. Data from healthy subjects were used to determine whether each levator muscle of the ptotic eyelids produced normal or less than normal force. The correct diagnosis was considered to be the diagnosis based on the findings at the time of surgery. The diagnosis of each patient with ptosis determined by eyelid excursion, eyelid excursion plus examination, levator force, and the levator force plus examination results were compared with the correct diagnosis. RESULTS: Eyelid excursion predicted the correct diagnosis 78.2% of the time. When eyelid excursion was combined with the examination results, the diagnosis was correct 84.0% of the time. Levator force predicted the correct diagnosis 95.2% of the time. When levator force was combined with the examination, the diagnosis was correct 97.9% of the time. CONCLUSION: Diagnosis of the cause of ptosis based on levator force measurement is significantly more accurate than when the diagnosis is based on eyelid excursion, even when information obtained on examination also is considered. Levator force measurement should be an integral part of ptosis evaluation.

Adolescent↗
PubMed1995

Topical fibronectin ophthalmic solution in the treatment of persistent defects of the corneal epithelium. Chiron Vision Fibronectin Study Group.

PURPOSE: We sought to evaluate the efficacy of topical fibronectin ophthalmic solution, containing 3.5 mg/ml of human fibronectin, in the treatment of persistent epithelial defects of the cornea. METHODS: In a double-masked, randomized clinical trial, patients with a persistent, corneal epithelial defect of at least 14 days in duration, and at least 2 mm in width along the larger axis, were sought from the practices of 38 clinical investigators. After a 14-day washout period, 65 patients were randomly assigned to one of three treatment groups. One group (n = 20) received fibronectin drops; the second (n = 23) received drops of the vehicle from the fibronectin solution; and the third (n = 22) received a placebo. RESULTS: After 21 days of treatment, there was no difference in percentage reduction of the corneal epithelial defect size; the average percentage of reduction of defect area ranged from 46.5% to 54.3%. Fibronectin treatment showed a beneficial effect for patients with larger baseline defects (10 mm2 or greater in area); however, no such effect was observed among patients with smaller defects. Defect duration before treatment had a significant effect on outcome (P = .007); defects of longer duration were less likely to decrease in size over the course of the study. CONCLUSIONS: All three treatment groups showed similar reductions in defect size; therefore, this study provides no support for the efficacy of fibronectin treatment of persistent, corneal epithelial defects. Defect duration showed a negative association with reduction in defect size. Because strict control of topical applications during the washout and treatment periods resulted in beneficial responses, physicians should carefully consider the topical medications used by patients who have persistent, corneal epithelial defects.

Administration, Topical↗
PubMed1995

Mitomycin C versus 5-fluorouracil in high-risk glaucoma filtering surgery. Extended follow-up.

PURPOSE: To compare the outcome of filtering surgery in high-risk patients using intraoperative mitomycin C (MMC) versus postoperative 5-fluorouracil (5-FU). METHODS: In a randomized clinical trial, the use of postoperative subconjunctival injections of 5-FU in 19 eyes of 19 patients was compared with a single intraoperative application of MMC in 20 eyes of 20 patients. All eyes were at high risk for failure of glaucoma filtering surgery. RESULTS: Follow-up ranged from 26 to 38 months (mean, 32.0 months). Three eyes in the MMC-treated group and two eyes in the 5-FU-treated group required subsequent surgery to control the IOP. Excluding these patients, intraocular pressure (IOP) averaged 9.0 +/- 4.9 mmHg in the MMC-treated eyes versus 16.3 +/- 4.6 mmHg in the 5-FU-treated eyes at the patient's last visit (P = 0.0003). Of the MMC-treated eyes, 81.3% had IOPs less than or equal to 12 mmHg compared with 26.7% of eyes in the 5-FU group (P = 0.0023). In the MMC-treated group, the average number of medications for IOP control at last visit was 0.5 +/- 0.8 compared with 1.6 +/- 1.3 in the 5-FU-treated group (P = 0.01). Late postoperative complications (those occurring more than 3 months after surgery) were similar for the two groups, with the exception of formation of a Tenon cyst in three of the eyes treated with MMC compared with none of the 5-FU-treated eyes. CONCLUSIONS: Eyes treated with MMC have lower IOP on fewer medications than eyes treated with 5-FU. Late postoperative complications are similar with the exception of an increased incidence of Tenon cyst formation in the MMC-treated eyes.

Antibiotics, Antineoplastic↗
PubMed1994

Measurements of upper eyelid and eyebrow dimensions in healthy white individuals.

Facial appearance is influenced by the anatomic relationship of the eyebrow and eyelid, and surgical procedures on these structures attempt to restore or preserve not only symmetry but also normal appearance. To provide useful benchmarks for such interventions, we measured the eyebrow height, upper eyelid crease height, and amount of visible pretarsal skin of 143 white subjects who had no facial abnormalities. An age effect was observed for all measures, indicating a direct relationship with age until the middle age range (41 to 60 years), when mean estimates leveled off or decreased somewhat relative to younger age groups. Within the 41- to 60-year age group, for example, the average (S.D.) values for pretarsal skin height, eyelid crease height, and eyebrow height were 1.4 mm (1.1 mm), 6.4 mm (1.2 mm), and 6.4 mm (1.8 mm), respectively. Eyebrow and pretarsal skin heights were greater in females than males, and eyelid crease height showed similar gender-related trends. With increasing age, variation around the mean estimates for eyelid and eyebrow measurement increased, which may be indicative of variability across individuals in the physiologic response to the aging process. As expected, a high degree of intereye correlation was observed (correlation coefficients of 0.87 to 0.96). These results emphasize the importance of providing a normal anatomic relationship that relates to the patient's age and gender, as well as an outcome that is symmetric, in corrective or cosmetic procedures on the eyelid and eyebrow.

Adolescent↗
PubMed1994

Antiviral therapy after penetrating keratoplasty for herpes simplex keratitis.

OBJECTIVE: To assess the efficacy of prophylactic topical antiviral therapy after penetrating keratoplasty for herpes simplex keratitis in the postoperative period and during the treatment of allograft rejection episodes with topical steroids. We used these data to make predictions of the sample size required to perform a prospective study of prophylactic oral acyclovir in the postoperative period. DESIGN: Retrospective review. SETTING: A university referral cornea service. PATIENTS: One hundred thirty-two consecutive penetrating keratoplasties for herpes simplex keratitis in 119 eyes of 118 patients. Only four grafts were performed in actively inflamed eyes. INTERVENTIONS: Sixty-six (52%) of the grafts performed in quiescent eyes received prophylactic postoperative topical antiviral treatment, three (2%) received oral acyclovir, and 59 (46%) received no antiviral therapy. The mean (+/- SD) duration of antiviral therapy was 12.8 +/- 22.5 months. MAIN OUTCOME MEASURES: Herpetic recurrence, allograft rejection episodes, and graft failure. RESULTS: Multivariate analysis showed that early antiviral use was associated with a decreased risk of herpes simplex keratitis recurrence (relative risk [RR] = 0.44; 95% confidence interval [CI], 0.21 to 0.94; P = .007) and allograft rejection (RR = 0.43; 95% CI, 0.25 to 0.75; P = .002). Graft failure was associated with herpetic recurrence within the first year (RR = 2.25; 95% CI, 1.09 to 4.64; P = .001) and allograft rejection episodes (RR = 2.56; 95% CI, 1.20 to 5.26; P = .003). Using these data, a prospective trial of postoperative oral acyclovir would require between 59 and 112 patients per group. CONCLUSIONS: Postoperative prophylactic antiviral treatment is associated with decreased rates of herpes simplex viral keratitis recurrence and allograft rejection. Early recurrence is associated with an increased risk of graft failure. A prospective study of postoperative oral acyclovir would require a multicentered approach.

Acyclovir↗
PubMed1994

Epidermal growth factor and insulin use in corneal preservation. Results of a multi-center trial. The Corneal Preservation Study Group.

PURPOSE: The ability of DexSol medium, supplemented with two growth factors, human epidermal growth factor (hEGF) and human insulin, to improve long-term endothelial survival after penetrating keratoplasty was evaluated in a multi-center, randomized, prospective, double-masked clinical trial. METHODS: Donor cornea pairs, one stored in DexSol and the other in DexSol with hEGF (10 ng/ml) and human insulin (10 micrograms/ml) (ProCell), were transplanted into 105 pairs of recipients matched by diagnosis and procedure and followed postoperatively for graft and endothelial survival. RESULTS: No primary donor failures occurred in either group. Graft clarity did not differ between the ProCell and DexSol groups at all postoperative periods: 3 months (98% versus 99%), 6 months (94% versus 98%), and 1 year (95% versus 97%), respectively. Postoperative complications (e.g., glaucoma, rejection) occurred with comparable frequencies in both groups. Mean endothelial cell loss did not significantly differ between the ProCell and DexSol groups at 3 months (5.7% versus 5.1%), 6 months (8.1% versus 10.1%), and 1 year (12.3% versus 15.6%), respectively. Similarly, there were no clinically and statistically significant differences in other endothelial morphometric parameters. CONCLUSIONS: The use of corneas stored in DexSol medium with added hEGF and insulin in corneal transplantation resulted in a safety and efficacy profile comparable with that observed in patients receiving DexSol-stored corneas; however, there were no clinically and statistically significant differences in postoperative endothelial morphometric parameters.

Adult↗
PubMed1993

Long-term visual outcome of ocular hypotension after thermosclerostomy.

Maximum intraocular pressure reduction is often the goal of glaucoma filtering procedures. To evaluate whether surgically induced ocular hypotension adversely affects visual acuity, we reviewed the visual outcome of 87 eyes of 67 patients who had undergone thermosclerostomy with follow-up of at least two years. Final visual acuity was compared in three groups on the basis of postoperative intraocular pressure level (< or = 10.0 mm Hg; > 10.0 mm Hg and < or = 21.0 mm Hg; and eyes that did not consistently fit solely in either group [mixed]). Average loss in visual acuity measured 1.8 +/- 3.0, 2.2 +/- 2.9, and 1.2 +/- 2.1 Snellen lines, respectively (P = .542). These data suggest that hypotensive eyes are not at greater risk for visual loss after glaucoma filtering procedures compared to normotensive eyes.

Aged↗
PubMed1993

Predictive factors for endothelial cell loss after penetrating keratoplasty.

To assess the influence of donor age, donor endothelial cell density, recipient age, and diagnosis on loss of endothelial cell density after penetrating keratoplasty, we evaluated endothelial cell density data from specular endothelial images collected during the follow-up penetrating keratoplasty surgeries performed from 1980 through 1985 at one center. Univariate and multivariate analyses of information from 265 grafts showed consistent and statistically significant associations between 1-year postoperative loss of endothelial cell density and donor age, donor endothelial cell density, and recipient age. Corneas obtained from older donors, corneas with higher donor endothelial cell density, and corneas transplanted to older recipients demonstrated greater percentage of loss of endothelial cell density 1 year after surgery. These three factors accounted for 17% of the total variance in percentage of loss of endothelial cell density 1 year after surgery.

Adolescent↗
PubMed1993

Diode laser surgery. Ab interno and ab externo versus conventional surgery in rabbits.

BACKGROUND: Fibroblastic proliferation of subconjunctival tissues remains a primary mechanism of failure in filtration surgery. Minimizing the surgical manipulation of episcleral tissues may reduce scarring. Laser sclerostomy surgery involves minimal tissue dissection, and is gaining attention as a method of potentially improving filter duration in high-risk cases. METHODS: Twenty-five New Zealand rabbits underwent filtration surgery in one eye, and the fellow eye remained as the unoperated control. Ten rabbits underwent ab externo diode laser sclerostomy surgery, ten underwent ab interno diode sclerostomy surgery, and five had posterior sclerostomy procedures. Filtration failure was defined as a less-than-4-mmHg intraocular pressure (IOP) difference between the operative and control eyes. RESULTS: The mean time to failure for the ab externo, ab interno, and conventional posterior sclerostomy techniques measured 17.4 +/- 11.5, 13.1 +/- 6.7, and 6.0 +/- 3.1 days, respectively. In a comparison of the laser-treated groups with the conventional procedure, the time to failure was significantly longer (P = 0.02) for the ab externo filter. The mean ab interno sclerostomy duration was longer than the posterior lip procedure, but this difference was not statistically significant (P = 0.15). The overall level of IOP reduction was similar in the three groups. CONCLUSIONS: These data suggest that diode laser sclerostomy is a feasible technique in rabbits, and the ab externo approach resulted in longer filter duration than the conventional posterior lip procedure in this model.

Animals↗
PubMed1993

Enhanced healing of cat corneal endothelial wounds by epidermal growth factor.

PURPOSE: The authors investigated whether healing of cat corneal endothelial wounds could be enhanced in vivo by human epidermal growth factor (EGF). METHODS: EGF was administered in sodium hyaluronate to the anterior chamber of cats after an endothelial touch injury. Control contralateral eyes received sodium hyaluronate alone. At selected times after injury, the corneas were evaluated for thickness, the rate of endothelial wound closure, the endothelial cell density, any variation in cell size, the percentage of hexagonal cells, and endothelial cell mitosis. RESULTS: Two days after injury, endothelial wounds of eyes treated with EGF had healed an average of 65 +/- 4% of the initial 38.5 mm2 wound area; paired control eyes had healed an average of 59 +/- 4% (P < 0.05). Both EGF-treated and control wounds had resurfaced over 90% of the initial wound area on day 4 after injury, and the wounds were completely resurfaced by 7 and 14 days after injury in both treatment groups. On days 4 and 7 after injury, the EGF-treated corneas were 5% and 8% thicker (835 versus 796 microns and 786 versus 728 microns, respectively) than the paired control corneas (P < 0.03). On days 10 and 14 after injury, both EGF-treated and control corneas were 19% and 12% thicker, respectively, than prewound the corneal thickness (621 microns). Seven days after injury, the corneas treated with EGF had an average of 76 +/- 28% more (P < 0.05) endothelial cell nuclei labeled with tritiated thymidine compared with that of the paired control eyes (2472 versus 1543 labeled nuclei). Fourteen days after injury, the central endothelial cell density of EGF-treated corneas was an average of 38 +/- 11% higher than that of the paired control eyes (P < 0.01, 1708 versus 1235 cells/mm2). The percentage of hexagonal cells in the wound area was an average of 14 +/- 4% higher (P < 0.01) than that of the paired control eyes (82% versus 69%), and the coefficient of variation of the cell size for EGF-treated corneas was an average of 31% (P < 0.05) smaller than that of the paired control corneas (0.21 versus 0.29 [standard deviation]/mean cell size). CONCLUSIONS: A single intraocular application of EGF formulated in sodium hyaluronate after an endothelial cell injury significantly enhanced multiple parameters that are closely related to improved endothelial cell regeneration.

Animals↗
PubMed1992

Optisol corneal storage medium.

We compared the safety and efficacy of Optisol (Chiron Ophthalmics, Irvine, California), a new corneal storage medium, with McCarey-Kaufman and Dexsol corneal storage media (Chiron Ophthalmics, Irvine, California) and K-Sol corneal storage medium (Cilco, Huntington, West Virginia). Optisol contains dextran, 2.5% chondroitin sulfate, vitamins, and precursors of adenosine triphosphate (adenosine, inosine, and adenine). In in vitro studies, rabbit and human corneas stored in Optisol were thinner after 12 to 14 days at 4 C than tissue stored in other media. Thymidine uptake showed increased mitotic activity in human corneal endothelial cells cultured in Optisol, compared to Dexsol. Specular microscopic fields showed larger are-as of visibly intact endothelial cells and ultrastructural examination disclosed fewer structural changes in endothelial cells stored in Optisol, compared to tissue stored in Dexsol. In vivo, no clinical signs of epithelial toxicity or histologic evidence of intraocular inflammation were observed in rabbit eyes in which Optisol drops were instilled four times a day for 14 days. Finally, 51 patients undergoing penetrating keratoplasty with tissue stored in Optisol for one to six days (mean, 3.6 days) were enrolled in an uncontrolled, open-label clinical study. The percentage of clear grafts (93%, 41 of 44 patients examined at three months; and 98%, 42 of 43 patients examined at six months) and endothelial cell loss (5.0% and 11.5% at three and six months, respectively) were comparable to data from previous studies that used tissue stored in other short-term and intermediate-term media. The results suggest that Optisol storage preserves corneal endothelial cells for up to two weeks at 4 C, thereby permitting flexibility in the use of donor tissue for corneal transplantation, and that Optisol storage yields thinner tissue, which may allow for more accurate evaluation and more effective surgical manipulation.

Adult↗
PubMed1992

Effects of eyelid protractor excision for the treatment of benign essential blepharospasm.

Data were analyzed from 37 patients with essential blepharospasm who had undergone upper eyelid protractor excision with brow suspension, and who had a median follow-up of 40 months (range, 12 to 83.5 months) after surgery. Of the 37 patients, 15 (40.5%) had sufficient relief of their spasms at their last follow-up; 22 patients (59.5%) had functionally significant recurrent or residual spasms after upper eyelid surgery. Of these 22 patients, 12 (55%) had recurrences more than six months after surgery, and four patients (18%) had recurrences more than one year after surgery. Patients with Meige syndrome were no more likely to experience recurrent spasms after upper eyelid surgery than patients who lacked a lower facial spasm component. Recurrence of symptoms was primarily the result of lower eyelid spasms in 11 patients (50%), upper eyelid spasms in one patient (5%), and all eyelids in six patients (27%). The location of recurrent spasms could not be ascertained in four patients (18%), with whom we had only telephone contact. Seven of 12 patients (58%) undergoing secondary procedures had relief from their spasms at the end of this study. Excluding those patients who chose to decline further surgery, 22 of 27 patients (81.5%) received satisfactory relief of symptoms after upper eyelid and, if needed, lower eyelid and repeat upper eyelid protractor excision. These long-term results are comparable to those reported previously for differential section of the facial nerve. Because the side effects of eyelid protractor excision are generally more acceptable, we recommend that when surgery is determined to be necessary for essential blepharospasm, upper eyelid protractor excision is the preferred surgical approach.

Aged↗
PubMed1992

A randomized, prospective, double-masked clinical trial of Optisol vs DexSol corneal storage media.

We compared Optisol and DexSol, two chondroitin-sulfate-based media for corneal storage at 4 degrees C, by transplanting 31 donor cornea pairs (one cornea stored in Optisol and its mate in DexSol for 20 to 134 hours) into 31 pairs of recipients (62 patients). All grafts were clear 1 year after transplantation except for one primary donor failure (Optisol group). Optisol-stored corneas were significantly thinner than DexSol-stored corneas after cardinal suture placement (0.64 mm vs 0.76 mm) and at the end of surgery (0.69 mm vs 0.78 mm); at all points afterward through 1 year the two groups did not differ. The activity of two lysosomal enzymes released into the media during storage, alpha-mannosidase and alpha-glucosidase, was lower in the Optisol group. Epithelial status and all endothelial morphometric parameters, except the figure coefficient at 1 year, did not differ between the two groups before surgery and 3, 6, and 12 months after surgery. Mean endothelial cell loss at 1 year was 15% for the Optisol group and 21% for the DexSol group (P = .22). Thus, Optisol-stored corneas were thinner during surgery than DexSol-stored corneas and there was less lysosomal enzyme activity in the Optisol medium after tissue storage. There were no significant differences in postoperative clinical or endothelial morphometric parameters, however.

Adult↗
PubMed1992

Pneumotonometry using sterile single-use tonometer covers.

Current methods for cleaning pneumotonometer tips include soaking the removable tip in various chemical agents. Disadvantages of this technique include the potential for incomplete disinfection, corneal contact with cleaning solutions, tip damage or loss, and soaking time. The authors studied the use of an available, disposable latex cover placed over the pneumotonometer tip for measuring intraocular pressure (IOP) in 46 eyes with normal corneas from a glaucoma screening clinic and 141 eyes with normal and abnormal corneas from a cornea and external disease clinic. The mean absolute IOP difference comparing with and without the tonometer cover was 1.6 mmHg for the glaucoma screening patients and 1.8 mmHg for the cornea clinic patients. A tonographic-like effect due to repeated tonometry also was shown. An additional study measuring a series of known IOP values in a cadaver eye showed no significant difference between uncovered and covered readings. These data suggest that placement of a disposable, latex cover over the pneumotonometer tip enables accurate IOP measurements and is a sanitary and convenient alternative method to repeated chemical disinfection.

Adolescent↗
PubMed1992

Intraoperative mitomycin versus postoperative 5-fluorouracil in high-risk glaucoma filtering surgery.

In a randomized clinical trial, the authors compared the use of postoperative subconjunctival injections of 5-fluorouracil (5-FU) in 19 eyes with a single intraoperative application of subconjunctival mitomycin (MMC) at the filtering site in 20 eyes at high risk for failure of glaucoma filtering surgery. Six months after surgery, intraocular pressures averaged 10.9 +/- 5.3 mmHg (mean +/- standard deviation) in the MMC-treated eyes versus 14.2 +/- 5.5 mmHg in the 5-FU-treated eyes (P = 0.08) and were less than or equal to 12 mmHg in 60.0% of MMC-treated eyes and 21.1% of 5-FU-treated eyes (P = 0.03). Mitomycin-treated eyes were receiving an average of 0.3 +/- 0.5 medications for intraocular pressure control, and 5-FU-treated eyes were receiving an average of 1.1 +/- 1.1 medications (P = 0.01). Drug-induced corneal epithelial defects were seen in nine 5-FU-treated eyes and in no MMC-treated eyes (P = 0.0004). These results suggest that intraoperative MMC may be a viable alternative to postoperative 5-FU, with lower overall intraocular pressures, decreased dependence on postoperative ocular antihypertensive medications, and decreased corneal toxicity.

Adult↗
PubMed1991

The effect of allograft rejection after penetrating keratoplasty on central endothelial cell density.

We identified all patients who had undergone penetrating keratoplasty for keratoconus and were being observed longitudinally (N = 174). During the follow-up period, 57 of 174 patients (33%) showed evidence of an allograft rejection episode, which occurred at an average of eight months after the operation. We analyzed specular photographs of the corneal endothelium, taken before and after the first allograft rejection episode. A significant decrease in endothelial cell density was observed (11.8%, P less than .0001). As a control, we analyzed all available specular photographs from patients with keratoconus who showed no evidence of allograft rejection after penetrating keratoplasty. The observed endothelial cell density decrease (11.8%) in patients with keratoconus undergoing allograft rejection exceeded that found in the control subjects (6.8%) during a comparable time period (P = .06). Severe allograft rejection episodes resulted in a decrease in endothelial cell density that exceeded expected loss significantly (14.8% compared with 6.9%, P = .01), whereas mild allograft rejection episodes were not associated with a loss in endothelial cell density exceeding that expected (1.8% compared with 6.5%, P = .34).

Endothelium, Corneal↗
PubMed1991

Long-term efficacy of orbital decompression for compressive optic neuropathy of Graves' eye disease.

In a retrospective evaluation of the long-term effect of transantral-ethmoidal decompression for compressive optic neuropathy, the authors evaluated visual acuity, visual fields, color vision, and motility in 30 patients (52 orbits) for a median follow-up period of 2.5 years (range, 0.6 to 6.5 years). Patients with preoperative visual acuity of 20/40 or better uniformly remained in this category and demonstrated an earlier stabilization of vision than those with poorer preoperative visual acuity. Of the ten patients whose preoperative visual acuity was 20/50 to 20/100, 80% attained acuity of 20/40 or better. In patients whose visual acuity was 20/200 or less (n = 7), 57% attained an acuity of 20/40 or better. The most common visual field defect was generalized constriction, which was noted in 43 of the 52 eyes (83%). After decompression, the preoperative visual field defect had improved or completely resolved in all but one case. Dyschromatopsia, noted in 20 eyes preoperatively, cleared in 17 (85%) postoperatively. Although the study showed that surgical decompression is beneficial, some patients may require additional modalities of treatment.

Adult↗