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D C Musch

Publications and source records attributed to D C Musch.

15 recordsLinked to original sources
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↗
PubMed1991

The effect of glaucoma filtering surgery on corneal endothelial cell density.

Corneal endothelial cell counts were obtained preoperatively and 3 months postoperatively in 46 eyes undergoing glaucoma filtering surgery. Average central endothelial cell loss in eyes without postoperative iridocorneal touch was 1.6%. In eyes with iridocorneal touch (Spaeth's grades 1 and 2), the average cell counts decreased by 7.1% and 9.3%, respectively. The average loss for combined grades 1 and 2 (8.1%) approached statistical significance (P +/- .06). The average loss in two patients with corneolenticular touch (Spaeth's grade 3) was greater than 50%. These findings suggest that early postoperative iridocorneal touch is unlikely to lead to corneal compromise in most eyes, but that corneolenticular touch can result in severe endothelial cell loss.

Aged↗
PubMed1990

Facial nerve injury and hemifacial spasm.

We studied evidence of facial nerve damage in patients with hemifacial spasm. Three types of evidence of nerve damage were analyzed: objectively measured weakness in eyelid protractor strength, clinically evident weakness of muscles innervated by the seventh nerve, and clinically evident aberrant seventh nerve regeneration. Of the 60 patients in the study, 54 (90%) had at least one of these features of seventh nerve damage. Objectively measured eyelid protractor weakness was noted in 27 of 58 patients (47%) who were tested. Clinically apparent weakness of at least one of four facial muscle groups was noted in 42 of 60 patients (70%). Aberrant seventh nerve regeneration was documented in 25 of 60 patients (42%). These findings indicate that facial nerve damage is common in patients with hemifacial spasm.

Adult↗
PubMed1990

Time course of thymoxamine reversal of phenylephrine-induced mydriasis.

We conducted a randomized, double-masked, paired comparison of 0.1% thymoxamine vs placebo for the reversal of phenylephrine-induced mydriasis. Mydriasis was induced with 2.5% phenylephrine in each eye of 74 subjects (148 eyes). Each subject then received 0.1% thymoxamine in one eye and placebo in the other eye. Pupillary measurements were obtained at regular intervals during the ensuing 8 hours. At all intervals, a greater percentage of thymoxamine-treated eyes returned to baseline pupillary diameters compared with placebo-treated eyes (P less than or equal to .01). For subjects in whom both pupils returned to baseline, thymoxamine-treated eyes returned to baseline in a mean of 2.2 hours, vs 5.2 hours for placebo (P less than .0001). Among thymoxamine-treated eyes, those with light irides responded more rapidly than those with dark irides, returning to baseline in 1.6 vs 2.8 hours, respectively (P = .0046). After constriction to baseline pupillary diameter had been achieved, no patients experienced a rebound dilation.

Adolescent↗
PubMed1990

Effects of pupillary dilation on automated perimetry in normal patients.

The effects of pupillary dilation (tropicamide 1%) on automated static threshold perimetry were studied in 18 normal subjects using the Humphrey field analyzer 30-2 and STATPAC programs. The mean defect worsened by 0.83 decibels (standard deviation, 0.92 decibels) in dilated fields as compared with baseline visual fields (P = 0.001). These findings indicate that pupillary dilation in healthy subjects who are not receiving ocular medications produces statistically significant declines in threshold sensitivities. Valid comparison of results from serial visual field testing, therefore, depends on control of or adjustment for the effect of pupillary dilation.

Adult↗
PubMed1990

Endothelial rejection following penetrating keratoplasty using Healon or BSS.

In order to evaluate the effect of a commonly used sodium hyaluronate preparation (Healon, Pharmacia AB, Uppsala, Sweden) on the incidence of endothelial rejection, endothelial cell loss, intraocular pressure, and corneal thickness after penetrating keratoplasty, we conducted a randomized clinical trial. Patients were allocated to receive Healon (n = 41) or BSS (Alcon Laboratories, Inc., Fort Worth, TX, U.S.A.; n = 37) during surgery. At 1 year after surgery, the Kaplan-Meier estimate of the proportion remaining free of endothelial rejection was 78.1% (SE 6.5%) in the Healon group, and 70.6% (SE 7.9%) in the BSS group. Survival analysis showed no overall difference in endothelial rejection between groups. The percent loss in endothelial cell density showed substantial variability within each group, but for those followed 2 years after surgery, the amount of loss was significantly less in Healon-treated patients (17.3% versus 30.2%). Four Healon patients required medication for intraocular pressure rises in the early postoperative period, and the average intraocular pressure 1 day after surgery was greater in the Healon group (18.2 versus 13.7 mm Hg). Corneal thickness was slightly greater in patients receiving Healon, but no clinically important differences were noted.

Acetates↗
PubMedDate not supplied

Epidermal growth factor and insulin in use in corneal preservation: study design and objectives of a multi-center trial.

This study determines whether endothelial survival after penetrating keratoplasty is improved by adding the mitogens, human epidermal growth factor (hEGF), and human insulin to a chondroitin-sulfate-based corneal storage medium. It is a multicenter, prospective, double-masked, randomized trial that compares endothelial survival of human corneal transplants using donor corneas that have been stored in one of two media: DexSol (CSM with 1% dextran) or DexSol containing recombinant hEGF and human insulin. This article describes the study design and entry characteristics of the 105 recipient pairs. Each donor pair of corneas is transplanted on the same day into recipients who are matched by diagnosis and procedure. Clinical parameters assessed on day 1, week 1, and 3, 6 and 12 months postoperatively include graft clarity, epithelial integrity, corneal thickness, visual acuity, and intraocular pressure. Postoperative endothelial survival for both groups will be determined by morphometric analysis of endothelial cell images before storage and at 3, 6, and 12 months postoperatively. Such analysis will also identify differences in polymegathism (cell size) or pleomorphism (cell shape).

Adult↗