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D J Apple

Publications and source records attributed to D J Apple.

At least 37 records · Page 2Linked to original sources
PubMed2001

Anterior capsule opacification: correlation of pathologic findings with clinical sequelae.

OBJECTIVE: To evaluate the degree of anterior capsule opacification (ACO) in human eyes obtained postmortem containing various rigid and foldable posterior chamber intraocular lens (PC-IOL) designs and compare the findings with clinical sequelae of capsular shrinkage. DESIGN: Comparative autopsy tissue study with clinicopathologic correlations. MATERIALS: Three hundred formalin-fixed human eyes containing the following PC-IOL styles were analyzed: (1) one-piece polymethyl methacrylate (PMMA) optic-PMMA haptic (n = 50), one-piece silicone-plate IOL, with large (2) or small (3) fixation holes (n = 35), (4) three-piece PMMA optic-Prolene haptic (n = 50), (5) three-piece acrylic optic-PMMA haptic (n = 55), three-piece silicone optic with PMMA (6) or polyimide (7) haptics (n = 30), and (8) three-piece silicone optic-Prolene haptic (n = 80) lenses. TESTING: The eyes were sectioned in the equatorial plane for gross examination of the capsular bag from a posterior view. The cornea and iris were then excised for evaluation from an anterior view. MAIN OUTCOME MEASURES: ACO was scored in each eye from 0 to IV, according to the degree/area of capsule opacification. Capsulorrhexis size and IOL decentration were measured with calipers. RESULTS: The overall differences among the IOL groups regarding the three parameters were significant (ACO score: P < 0.001; capsulorrhexis diameter: P = 0.036; IOL decentration: P = 0.012). Mean ACO scores were highest with the large- and small-hole one-piece silicone-plate lenses (2.543 +/- 0.950) and lowest with the three-piece acrylic optic-PMMA haptic lenses (0.600 +/- 0.710). Of 10 cases of capsulorrhexis phimosis observed in the study, 7 cases were associated with three-piece silicone optic-Prolene haptic lenses, which also presented the highest mean decentration (0.375 +/- 0.601 mm). CONCLUSIONS: Our results confirm previous histopathologic observations that the rate of ACO is the lowest with acrylic lenses and higher with plate-haptic silicone IOLs. Nevertheless, clinical sequelae of capsular shrinkage are also very important with three-piece silicone optic-Prolene haptic designs. Thus, IOL material and design are significant factors in the development of ACO, but they ultimately also influence the clinical presentation of capsular shrinkage.

Acrylic Resins↗
PubMed2001

Effect of in-the-bag intraocular lens fixation on the prevention of posterior capsule opacification.

PURPOSE: To compare the incidence of posterior capsule opacification (PCO) after extracapsular cataract extraction (ECCE) and phacoemulsification and to evaluate the role of posterior chamber intraocular lens (PC IOL) haptic fixation and biomaterial/design in reducing the incidence. SETTING: Postgraduate Institute of Medical Education and Research, Chandigarh, India; Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. METHODS: This study comprised 278 eyes of 263 patients having ECCE and 318 eyes of 297 patients having phacoemulsification with PC IOL implantation. Posterior capsule opacification leading to a decrease in Snellen visual acuity of 2 or more lines was considered visually significant. The presence of PCO and IOL haptic fixation were evaluated postoperatively using slitlamp biomicroscopy. Haptic position was noted as in-the-bag (B-B), 1 haptic in the bag and 1 in the sulcus (bag-sulcus [B-S]), or both haptics out of the bag (sulcus-sulcus [S-S]). In addition, the rate of visually significant PCO was compared among 3 IOL biomaterials: poly(methyl methacrylate), silicone, and hydrophobic acrylic. RESULTS: Visually significant PCO occurred in 42.45% of eyes having ECCE and 19.18% of eyes having phacoemulsification (P <.001, chi-square test) after a mean follow-up of 2.4 years +/- 0.7 (SD). In both groups, visually significant PCO was significantly less in eyes with B-B fixation than in those with B-S or S-S fixation (P <.001). The rate of visually significant PCO in all eyes in the phacoemulsification group with B-B fixation was low (11.90%) and was significantly lower in eyes with a hydrophobic acrylic IOL (2.22%; P <.05, chi-square test). CONCLUSIONS: In-the-bag PC IOL fixation is required to consistently reduce the incidence of PCO. Thorough removal of lens substance, including hydrodissection-assisted cortical cleanup, and in-the-bag PC IOL fixation seem to be the most important factors in reducing PCO, regardless of surgical procedure or IOL type used. Intraocular lens biomaterial and design also help prevent PCO.

Biocompatible Materials↗
PubMed2001

No-anesthesia clear corneal phacoemulsification versus topical and topical plus intracameral anesthesia. Randomized clinical trial.

PURPOSE: To compare the intraoperative pain scores during clear corneal phacoemulsification under no anesthesia, topical anesthesia, and topical plus intracameral anesthesia. SETTING: Dr. Agarwal's Eye Hospital and Eye Research Center, Chennai, India. METHODS: Seventy-five patients were randomized to have phacoemulsification under no anesthesia, topical anesthesia, or topical plus intracameral anesthesia. Uncooperative or illiterate patients and those with hard cataract, a shallow anterior chamber, or small pupils were excluded. A protocol was established for supplemental anesthesia in case of breakthrough pain during the surgery. Each patient was asked to grade the overall severity of intraoperative pain immediately after surgery on a 10-point visual analog scale. Also evaluated were the general discomfort during surgery, discomfort from the microscope lights, surgeon stress during surgery, and total surgical time. Comparison among the 3 groups was performed using an analysis of variance. RESULTS: No supplemental anesthesia was required in any group. No significant difference was noted in the mean scores of the subjective sensation of pain with or without topical anesthesia (P =.610). The mean scores of patient discomfort from the microscope lights and surgical time were also statistically insignificant. Patient discomfort and surgeon stress during surgery were significantly greater in the no-anesthesia group than in the topical and topical plus intracameral groups (P =.0235 and P = 0.0206, respectively). CONCLUSION: No-anesthesia clear corneal phacoemulsification was performed by a highly experienced, skilled surgeon without causing an unacceptable level of pain. However, this technique is not suitable for every cataract surgeon or patient.

Adult↗
PubMed2001

Dense opacification of the optical component of a hydrophilic acrylic intraocular lens: a clinicopathological analysis of 9 explanted lenses.

PURPOSE: To report clinical, pathological, histochemical, ultrastructural, and spectrographic analyses of explanted hydrophilic acrylic intraocular lenses (IOLs) obtained from patients who had visual disturbances caused by postoperative opacification of the lens optic. SETTING: Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA, and Ege University, Alsancak Izmir, Turkey. METHODS: Nine hydrophilic IOLs (SC60B-OUV, MDR Inc.) were explanted from 9 patients with decreased visual acuity. Most patients became symptomatic approximately 24 months after uneventful phacoemulsification and IOL implantation. Opacification was noted and appeared clinically to be associated with a fine granularity within the substance of the IOL optic. The IOLs were forwarded to the center and examined by gross and light microscopy. Full-thickness cut sections of the optics were stained with 1% alizarin red and the von Kossa method (special stains for calcium). Some were submitted for scanning electron microscopy and energy dispersive x-ray spectroscopy. RESULTS: Microscopic analyses revealed multiple fine, granular deposits of variable sizes within the lens optics, usually distributed in a line parallel to the anterior and posterior curvatures of the optic, with a clear zone just beneath the optic surface. The deposits stained positive with alizarin red and the von Kossa method. Energy dispersive x-ray spectroscopy of the internal substance of sectioned IOLs demonstrated the presence of calcium within the deposits. CONCLUSION: This is the first clinicopathological report of optic opacification occurring with this hydrophilic acrylic IOL model. Studies of similar cases with this lens should be done to determine the incidence and possible mechanisms of the phenomenon.

Acrylic Resins↗
PubMed2001

Effect of heparin surface modification in reducing silicone oil adherence to various intraocular lenses.

PURPOSE: To evaluate surface properties of various intraocular lenses (IOLs), including a newly fabricated heparin-surface-modified (HSM) silicone IOL, with special reference to their efficiency in reducing potential silicone oil adherence to the IOL optics. SETTING: Center for Research on Ocular Therapeutics and Biodevices, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. METHODS: Five groups of rigid and foldable IOLs were analyzed in an in vitro test for the percentage of silicone oil adherence: a single-piece foldable hydrophilic-acrylic IOL (n = 9); a single-piece rigid poly(methyl methacrylate) (PMMA) IOL with HSM coating of the lens optic (n = 9); a 3-piece foldable silicone optic IOL with HSM coating of the optic (n = 10); a single-piece standard rigid PMMA IOL (n = 7); and a standard 3-piece foldable silicone optic IOL (n = 9). After the IOLs were immersed in water and then in silicone oil, gross photographs taken. Image analysis was performed to evaluate the percentage of silicone oil coverage of the anterior and posterior surfaces of each IOL optic. RESULTS: The mean silicone oil coverage of the hydrophilic-acrylic IOLs was 5.6% +/- 2.5% (SD); of the HSM PMMA IOLs, 6.2% +/- 4.3%; of the HSM silicone optic IOLs, 6.7% +/- 3.2%; and of the standard PMMA IOLs, 20.3% +/- 13.3%. The mean silicone oil coverage was greatest on the standard silicone optic IOLs, 98.2% +/- 3.1%. CONCLUSIONS: Intraocular lenses with a hydrophilic optic have less tendency toward adherence to silicone oil than more hydrophobic designs. A foldable silicone IOL with heparin surface modification can significantly reduce potential silicone oil adherence, comparable to the level achievable with the rigid HSM PMMA designs. Two new foldable IOL styles, the HSM silicone IOL and IOLs in the general class of hydrophilic-acrylic, were highly efficacious in reducing silicone oil adherence. There is now a real choice of foldable lenses for patients with actual or potential vitreoretinal diseases.

Acrylic Resins↗
PubMed2001

[Influence of surgery-related factors on the Nd:YAG laser capsulotomy rates of 3-piece silicone IOLs - analysis of 457 pseudophakic human globes obtained post mortem].

BACKGROUND: The purpose of this study was to analyze any possible surgical reasons which may have had caused posterior capsule opacification in 3-piece silicone IOLs that had required Nd:YAG laser treatment. Special attention was given to 1) quality of cortical clean up, 2) type of haptic fixation, and 3) continuous curvilinear capsulorhexis (CCC) size and shape. MATERIALS AND METHODS: Human eyes obtained post-mortem implanted with 3-piece silicone optic - PMMA haptic (SI 40 NB) and 3-piece silicone optic - Prolene haptic (SI 30 NB) designs IOLs, accessioned between January 1993 and December 2000 were evaluated by gross examination from behind under an operating microscope using the Miyake-Apple posterior photographic technique. The area and intensity of Soemmerring's ring and type of fixation was studied in 457 eyes. The mean diameter of the CCC and relation of the CCC edge to the optic rim were analyzed in 221 eyes. RESULTS: 1) The amount of Soemmerring's ring formation was significantly larger in the group of IOLs requiring Nd:YAG capsulotomy in both the SI 40 NB and SI 30 NB design than in the IOLs without capsulotomies. 2) The percentage of not in-the-bag fixated IOLs in both the SI 40 NB and SI 30 NB design was larger in the "Nd:YAG groups", without being statistically significant. 3) The "Nd:YAG groups" showed a significant higher amount of non overlapping clock hours of the CCC edge in relation to the optic rim. CONCLUSION: 1) The data confirm the clinical assumption that the incidence of PCO is correlated with the cortical clean up. 2) Our findings also support the clinical assumption, that poor IOL fixation increases the risk of PCO. 3) This study also verifies the relation of the CCC to PCO, namely a relatively small CCC covering the entire optic rim is best to reduce the Nd:YAG laser rate.

Cataract↗
PubMed2001

[Postoperative opacification of posterior chamber intraocular lenses - a review].

Postoperative opacification of intraocular lenses (IOLs) is a very unpleasant complication for the ophthalmic surgeon and the patient. We report on our experiences with opacification of different foldable IOL designs and rigid poly (methyl methacrylate) (PMMA) posterior chamber lenses.1. Snowflake degeneration of PMMA IOLs: This condition is an unanticipated and surprising late postoperative finding 8 to 15 years after implantation. In our opinion, this complication is probably not related to the PMMA biomaterial itself, but rather it appears to represent a manufacturing problem that has affected a selected, albeit large number of lenses manufactured in the 1980s-mid 1990s.2. Degeneration of UV absorber material and calcium deposits within the optic of hydrophilic IOLs: Two years postoperatively degenerations of UV absorber material and calcium deposits within the optic of single piece hydrophilic acrylic lenses SC60B-OUV manufactured by MDR (Medical developmental research Inc. Clearwater FL, USA) can occur. Although the precise mechanism is not fully known, it was assumed that these opacifications are due to premature aging of the UV blocking agent incorporated in the lens biomaterial and calcification.3. Calcification on the surface of the Bausch & Lomb Hydroviewtrade mark IOLs: Twelve to 15 months postoperatively granular surface calcifications in Hydroviewtrade mark IOLs occured. The mechanism is not fully understood. According to Bausch and Lomb studies, part of the components of the packaging contained silicone, which may have come off the packaging onto the lens optic, where it then appears to be a catalyst for calcium precipitation. The manufacturer has correlated a change in packaging with the appearance of the opacification. The manufacturer now believes that this problem has been solved. However, final verification will require a careful 1 - 2 years clinical study.4. Glistenings in the hydrophobic acrylic AcrySoftrade mark IOLs: The time frame of glistenings in the AcrySoftrade mark IOLs is highly variable. It has been suggested that the occurrence of glistenings may be related to variations in the temperature of the lens just prior to and or during insertion into the eye. Formation of vacuoles may occur within the submersed acrylic polymer when there is a transient increase and then decrease in temperature during the surgical procedure. "Glistenings" may then subsequently form by ingress of anterior chamber fluid. Contrast sensitivity can been decreased in some patients, but clinically significant decrease of visual acuity has been rare.

Biocompatible Materials↗
PubMed2001

[Millenniums update on posterior capsule opacification (PCO) scores, centration, biocompatibility and fixation of foldable intraocular lenses (IOL) - an analysis of 1,221 pseudophakic post mortem globes].

BACKGROUND: The ongoing and fast evolution of foldable IOL designs established the necessity to evaluate the different abilities of each lens style. The large IOL database (over 16,500 specimens) acquired in our laboratory, has permitted us to perform a clinico-pathological analysis on pseudophakic autopsy globes provided from sources worldwide, especially many Lions Eye banks in the United States. MATERIAL AND METHODS: We analyzed 6 foldable IOL styles commonly implanted in the United States, using one type of rigid IOL design (1-piece design rigid PMMA optics) as a comparison group. Posterior capsule opacification (PCO) score, decentration, fixation, presence or absence of a Nd:YAG laser posterior capsulotomy and area and intensity of Soemmerring's ring formation was discerned by examination under an operating microscope using the Miyake-Apple posterior photographic technique. RESULTS: The four lenses with the lowest rates ranging between 3.8 % and 21.7 % are modern designs, mostly implanted after 1992. The two lenses with the higher rates ranging between 23.1 % and 30.4 %, were all older designs, already prevalent prior to 1992. IOL fixation with both haptics in the capsular bag showed the best centration values and PCO scores. Our studies to date have shown in a preliminary fashion that the AcrySoftrade mark IOL displays the the lowest (best) biocompatibility score. CONCLUSIONS: Entering the new millenium, with evolution of modern surgical techniques and IOL designs, the incidence of the two major complications of cataract surgery, decentration and PCO are now finally diminishing.

Autopsy↗