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Randall J Olson

Publications and source records attributed to Randall J Olson.

At least 37 records · Page 2Linked to original sources
PubMed2005

Cohort study of 27 cases of endophthalmitis at a single institution.

PURPOSE: To identify potential risk factors associated with post-cataract surgery bacterial endophthalmitis. SETTING: The John A. Moran Eye Center, Salt Lake City, Utah, USA. METHODS: This retrospective cohort study consisted of patients who had surgery for cataract(s) at this eye hospital. A 10% sampling of all patients operated on for cataract surgery from January 1, 1996, to December 31, 2002, were compared with all cases of postcataract surgery bacterial endophthalmitis during this same time period at this institution. The main outcome measure(s) included surgical complication, first postoperative day wound leak, incision placement and location, intraocular lens material, whether a suture was placed, antibiotic used, collagen shield use, and whether the eye was patched. RESULTS: A total of 1525 patients were in the control cohort, and there were 27 cases of endophthalmitis. In a multivariate regression analysis, the factors found to be statistically associated with endophthalmitis were (1) wound leak on the first postoperative day (odds ratio [OR] 44 +/- 42; confidence interval [CI] 6.85 to 287; P<.001); (2) capsular or zonular surgical complication (OR 17.2 +/- 14.2; CI 3.44 to 86.4; P=.001); (3) topical antibiotic started the day after surgery rather than the day of surgery (OR 13.7 +/- 12.9; CI 2.17 to 90.9; P=.005); (4) use of ciprofloxacin rather than ofloxacin topically after surgery (OR 5.3 +/- 3.6; CI 1.41 to 20.0; P=.014); (5) not patching after surgery (OR 7.1 +/- 5.6; CI 1.47 to 36.4; P=.015); and (6) not placing a collagen shield soaked in antibiotic (OR 2.7 +/- 1.3; CI 1.06 to 7.14 P=.037). CONCLUSION: In sutureless cataract surgery, surgical complications and wound leak on the first postoperative day were most strongly associated with endophthalmitis.

Aged↗
PubMed2005

Late in-the-bag intraocular lens dislocation: incidence, prevention, and management.

Dislocation of an intraocular lens (IOL) with the capsular bag is a late complication of cataract surgery, reported with increasing frequency in recent years. Pseudoexfoliation, uveitis, myopia, and other diseases associated with progressive zonular weakening and capsular contraction are the predisposing conditions. Capsular tension rings probably help but do not prevent this complication. Management includes IOL exchange, replacement with an anterior or a sutured posterior chamber IOL, or suturing the IOL through the bag to the iris or the sclera.

Foreign-Body Migration↗
PubMed2005

Surface calcification of a 3-piece silicone intraocular lens in a patient with asteroid hyalosis: a clinicopathologic case report.

OBJECTIVE: To illustrate the laboratory findings in a patient with bilateral asteroid hyalosis who presented with calcified deposits on a 3-piece silicone intraocular lens (IOL). DESIGN: Observational case report. METHODS: A 76-year-old diabetic woman underwent uneventful cataract surgery in 1994 with implantation of a silicone-optic polypropylene-haptic IOL in the left eye. A neodymium:yttrium-aluminum-garnet (Nd:YAG) laser posterior capsulotomy was performed 2 years after cataract surgery, but persistent whitish deposits were observed on the posterior optic surface of the lens. Over the next 3 years, the opacification increased in the region corresponding to the capsulotomy. The IOL was explanted/exchanged. The right eye had cataract surgery in 1995. The acrylic lens implanted in this eye developed no opacities after 6 years. MAIN OUTCOME MEASURES: Gross, microscopic, and surface analyses of the explanted IOL. RESULTS: Gross and light microscopic analyses revealed the presence of confluent crustlike deposits on the central area of the posterior optic surface, as well as Nd:YAG pits. Individual spherules exhibiting a Maltese-cross pattern under polarizing light were also observed. Energy dispersive x-ray spectroscopic analyses demonstrated the composition of the confluent deposits to be similar to hydroxyapatite. CONCLUSIONS: An association between asteroid hyalosis and dystrophic calcification of IOLs has been reported only with silicone plate haptic designs. The material opacifying the 3-piece silicone lens probably was derived from the asteroid bodies or from the process that results in this vitreous condition. Clinical evaluation of other pseudophakic patients with asteroid hyalosis will confirm if this phenomenon is restricted to silicone IOLs.

Aged↗
PubMed2004

Surface calcification of silicone plate intraocular lenses in patients with asteroid hyalosis.

PURPOSE: To report three cases in which a silicone-plate lens was explanted because of whitish deposits on the posterior optic surface. DESIGN: Observational case series with clinicopathological correlation. PATIENTS AND METHODS: In the three instances, the deposits were observed at least 2 years after uneventful cataract surgery. All of the patients had unilateral mild asteroid hyalosis in the concerned eye. After explantation of the lenses, gross and light microscopic analyses were performed. The posterior optic surfaces of the lenses also underwent scanning electron microscopy coupled with energy dispersive x-ray spectroscopy for analysis of the elemental composition of the deposits. RESULTS: Gross and light microscopic analyses revealed well-demarcated areas of whitish deposits on the posterior optic surface of the lenses, as well as multiple pits caused by Neodymium:yttrium aluminum garnet laser treatments. The deposits formed an amorphous layer with a "crustlike" appearance, which was confirmed by scanning electron microscopy. X-ray spectroscopy analyses demonstrated the composition of the deposits to be similar to hydroxyapatite. CONCLUSIONS: The material opacifying the lenses was probably derived from the asteroid bodies or from a similar process that results in this vitreous condition. We were unaware of this association between asteroid hyalosis and late postoperative dystrophic calcification of silicone lenses.

Aged↗
PubMed2004

The effect of lens edge design versus anterior capsule overlap on posterior capsule opacification.

PURPOSE: To determine whether lens edge design or anterior capsule overlap on the intraocular lens (IOL) has greater effect on posterior capsule opacification (PCO). DESIGN: Retrospective cohort clinical study. METHODS: Retrospective. SETTING: Academic clinical practice. PATIENT POPULATION: The patient population consisted of 259 uncomplicated surgical patients (259 eyes) with no confounding comorbidity and at least 1 year of follow-up after surgical placement of a silicone or hydrophobic acrylic lens. OBSERVATION PROCEDURES: Digital retroilluminated photographs were taken to ascertain PCO, anterior capsular opacification (ACO), previous neodymium:YAG capsulotomy and degree of anterior capsule overlap on the IOL optic. MAIN OUTCOME MEASURES: PCO, ACO, YAG capsulotomy rate, and anterior capsule overlap on the IOL optic. RESULTS: One hundred forty-eight digital images (74 silicone and 74 acrylic) were measurable for both anterior capsule overlap and PCO. Complete 360 degrees of anterior capsule overlap on the IOL was associated with decreased PCO (P = <.001). A significant negative correlation was found between the degree of anterior capsule overlap and PCO (P = <.001). Evaluation of PCO, and YAG capsulotomy rates were similar between acrylic and silicone lenses. Minimal anterior capsule overlap may also be associated with PCO prevention. CONCLUSIONS: Implanting a lens with complete anterior capsule overlap on the IOL was found to significantly reduce PCO, which advantage appeared to be greater than PCO prevention by a truncated, sharp edge IOL design.

Acrylic Resins↗
PubMed2004

Legacy AdvanTec and Sovereign WhiteStar: a wound temperature study.

PURPOSE: To assess the wound temperature of the Sovereign WhiteStar (S-WS) (AMO) and Legacy AdvanTec (L-ADV) (Alcon) phacoemulsification systems. SETTING: John A. Moran Eye Center, Health Sciences Center, University of Utah, Salt Lake City, Utah, USA. METHODS: Phacoemulsification using 20-gauge, 30-degree straight tips with the L-ADV and S-WS systems was performed in fresh cadaver eyes. The power was set at 50%, and aspiration was 12 mL/min; the L-ADV was run at 15 pulses per second (pps) and the S-WS at WS CF (6 milliseconds on, 12 milliseconds off). Temperature was measured at 5-second intervals for 60 seconds using a microthermistor placed in the wound. The phaco tip was angled 30 degrees to increase wound-tissue contact. At 10 seconds, the flow was clamped to simulate occlusion. Five runs, sleeved and unsleeved, were averaged for the phaco tip. RESULTS: The mean temperature was significantly higher with L-ADV than with S-WS (from 10 seconds on in the sleeved condition and from 5 seconds on in the unsleeved condition after the aspiration line was clamped). In 2 of 5 sleeved runs and 4 of 5 unsleeved runs, the L-ADV handpiece decreased power as the temperature increased. One run with the L-ADV with sleeve showed signs of wound burn. There were no signs of wound burn with the S-WS. The highest temperature recorded was 57.5 degrees C with the L-ADV and 38.6 degrees C with the S-WS. Power tests showed L-ADV protected the stroke length and S-WS had constant power except in air where it increased power. CONCLUSIONS: There was less increase in wound temperature over time with the S-WS than with the L-ADV system in sleeved and unsleeved simulated surgery in human eye-bank eyes. Because the ultrasound handpieces respond differently under different load scenarios, meaningful comparisons of pulsing features are difficult to create.

Anterior Eye Segment↗
PubMed2004

Reducing the risk of postoperative endophthalmitis.

Recent literature suggests that the incidence of postoperative endophthalmitis is variable and may be on the rise. This article reviews established perioperative preventative measures, and discusses some possible causes of postoperative endophthalmitis that may be insufficiently addressed by current risk reduction techniques. This article also considers future measures for reducing the risk of postoperative endophthalmitis.

Antibiotic Prophylaxis↗
PubMed2004

Clinical experience with 21-gauge manual microphacoemulsification using Sovereign WhiteStar Technology in eyes with dense cataract.

PURPOSE: To present a series of patients who had 21-gauge microphacoemulsification using Sovereign WhiteStar technology. SETTING: John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, Utah, USA. METHODS: Eighteen consecutive patients with cataracts judged to be 3+ or 4+ on a 4-point scale were prospectively monitored for complications, energy used during phacoemulsification, and results 1 day and 3 months postoperatively. RESULTS: No complications occurred during nucleus removal. On a 4-point scale, the mean level of inflammation at 1 day was 0.9 +/- 0.5 (SD), with 13 patients having no corneal edema. Seven patients had an uncorrected visual acuity of 20/40 or better on the first postoperative day. At 3 months, all corneas were clear, there was no sign of anterior chamber inflammation, and all patients had a best corrected visual acuity of 20/25 or better (best-case analysis). CONCLUSION: Results show that 21-gauge microphacoemulsification with Sovereign WhiteStar technology is safe and effective for removal of hard cataracts.

Cataract↗
PubMed2003

Cataract treatment in the beginning of the 21st century.

PURPOSE: To describe the principles upon which present day cataract treatment success resides. DESIGN: Literature review and collective experience of the authors. RESULTS: Surgical removal remains the standard treatment for cataract now and in the foreseeable future. Ultrasound cataract removal with a foldable "in-the-bag" intraocular lens with a truncated edge treated for dysphotopsia best correlates with core treatment principles, as we now understand them. Improving refractive results is an important trend. The worldwide burden of this problem is immense. CONCLUSIONS: While results for treatment of cataracts are excellent today, improvements in safety and refraction precision are needed. Other approaches are desperately needed to stem the worldwide tide of cataract related ocular dysfunction.

Cataract↗
PubMed2003

A clinical comparison of single-piece and three-piece truncated hydrophobic acrylic intraocular lenses.

PURPOSE: To determine the clinical differences between three-piece (3P) and single-piece (SP) truncated hydrophobic acrylic intraocular lenses (IOL). DESIGN: Retrospective cohort clinical study. METHODS: The setting was an academic clinical practice. The patient population consisted of subjects without confounding comorbidity that could effect central vision with at least 1-year follow-up after uncomplicated surgical placement of 3P or SP IOLs in the capsular bag and at least 20/25 best-corrected postoperative vision documented. Observation procedures were as follows: logarithm of the minimal angle of resolution (LogMAR) visual acuity (uncorrected and best corrected), digital retroillumination photographs to ascertain posterior capsular opacification (PCO), anterior capsular opacification (ACO), IOL centration, and refractive stability by comparing this refraction with the early postoperative refraction. Patients completed a dysphotopsia questionnaire. Main outcome measures were as follows: LogMAR visual acuity (uncorrected and best corrected), PCO, ACO, IOL centration, refractive stability, and dysphotopsia outcomes comparing 3P and SP. RESULTS: Seventy-five patients were enrolled (36 3P and 39 SP). Corrected and uncorrected visual acuity, refractive stability, and IOL centration were similar. Single piece truncated hydrophobic acrylic intraocular lenses had more PCO (P =.013), less ACO (P =.001), less central flash looking at a peripheral light (P =.044), and less unwanted images to the side of a light source (P =.025) . CONCLUSIONS: Although similar in centration and refractive stability, SP has more PCO, less ACO, and less dysphotopsia than 3P.

Acrylic Resins↗
PubMed2003

Efficacy and wound-temperature gradient of whitestar phacoemulsification through a 1.2 mm incision.

PURPOSE: To evaluate the efficacy and wound-temperature gradients of WhiteStar micropulse technology using bimanual phacoemulsification without an irrigation sleeve through a 1.2 mm incision. SETTING: Island Eye Surgicenter, Carle Place, New York, USA. METHODS: Ten patients had bimanual phacoemulsification using micropulse technology without an irrigation sleeve through a 1.2 mm clear corneal incision. A thermocouple consisting of a 30-gauge copper wire was inserted into clear cornea directly adjacent to the wound to digitally record temperature gradients at the wound. Endothelial cell counts were evaluated preoperatively and postoperatively in all patients. RESULTS: All 10 patients maintained corneal clarity with no sign of thermal damage to the wound. The maximum corneal wound temperatures during phacoemulsification ranged from 24 degrees C to 34 degrees C, well below the temperature of collagen shrinkage. The endothelial cell loss at 3 months was 7%. CONCLUSIONS: Because of the decreased thermal effect with WhiteStar technology, an irrigation sleeve over the phacoemulsification needle is superfluous. As a result, bimanual phacoemulsification can be safely performed through a 1.2 mm incision.

Body Temperature↗
PubMed2003

White Star technology.

White Star micropulse technology is a software modification that allows extremely short bursts of ultrasound energy. Studies have shown that this decreases wound heat build-up with the retained efficiency of continuous ultrasound. Decreased energy utilization with improved corneal function and improved nuclear fragment followability appear to be additional benefits.

Hot Temperature↗
PubMed2003

The "demise" of diagnostic and research ocular pathology: temporary or forever?

PURPOSE: Several authorities have documented a significant decrease in support for modern eye pathology/pathology research laboratories. Indeed, many laboratories have closed or suffered marked cutbacks. The purpose of this report is to ask why this is so and to seek a possible means for reversing this trend. METHODS: Observations from the senior author's experience and a case from author's facility are analyzed. RESULTS: There are several reasons for ocular pathologists' difficulties, such as financial problems, lack of vision, personality conflicts, and problems with the departmental administration. Until recently, most research and development in several subspecialty fields of ophthalmology, including biodevices research, has been done primarily by engineers and in-house workers in industry. This precludes proper independent, nonbiased control and guidance from academia. Most ocular pathologists have not participated in this relatively new and wide-open field. CONCLUSIONS: We suggest a new realm of activity for today's newly trained ocular pathologists. Based on personal experience of two decades of fruitful collaboration with industry, we believe that ocular pathologists are uniquely trained to apply their expertise to various new fields of research that most pathologists today have not utilized. An important example is research on clinicopathological aspects of implantable biodevices. In addition, support and oversight should be provided by the major ophthalmic societies, such as the American Academy of Ophthalmology, in order to retain (even regain) control over this field. This is mandatory in order to control the safety and efficacy of new drugs and devices being introduced almost daily. Only then can clear differentiation between profit and patient welfare be achieved as potentially dangerous devices and techniques are let loose on the market. The field of "routine, descriptive" eye pathology is severely wounded and will return only in an attenuated fashion. In general, full-time support for ocular pathologists will not be possible unless they seek extra support from the private sector, engage in a concurrent clinical practice, or are supported by an endowed chair (a wonderful alternative).

Financing, Government↗
PubMed2002

Accuracy and reproducibility of biometry using partial coherence interferometry.

PURPOSE: To determine whether partial coherence interferometry is comparable to standard contact ultrasonic biometry in accuracy, reproducibility, and ease of use. SETTING: Academic university practice. METHODS: In this prospective study, simultaneous biometry was performed in 91 consecutive patients (111 eyes) using partial coherence interferometry (IOLMaster, Zeiss Humphrey Systems) and ultrasonic biometry (I(3), Innovative Imaging, Inc.). The differences between the predicted spherical equivalent in diopters (D) and the actual results with both techniques were compared. RESULTS: The IOLMaster was significantly better in the mean absolute error (0.533 D +/- 0.589 [SD] versus 0.757 +/- 0.723 D; P = .012) and the percentage of eyes within +/-0.5 D (61.2% versus 42.3%; P = .003) and +/-1.0 D (87.4% versus 77.5%; P =.05) of the predicted refraction. CONCLUSION: The IOLMaster was more accurate and reproducible than the contact ultrasonographic technique.

Biometry↗
PubMed2002

In vitro comparison of glistening formation among hydrophobic acrylic intraocular lenses(1).

PURPOSE: To compare glistening formation induced by temperature stressing in vitro among hydrophobic acrylic intraocular lenses (IOLs) available in the United States. SETTING: John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. METHODS: Wagon Wheel (WW) packaged 1-piece AcrySof IOLs (Alcon), WW-packaged 3-piece AcrySof IOLs, and Sensar IOLs (Allergan Medical Optics) were analyzed in vitro for 5 consecutive days. Ten IOLs of each type were inserted into viewing chambers filled with balanced salt solution, maintained at 37 degrees C, and evaluated every 24 hours at 37 degrees C and then, after a 2-hour cooling, at room temperature. The IOLs were examined by slitlamp to quantify glistenings and by digital photography to determine glistening size. RESULTS: The glistening quantity was minimal and did not differ among IOL types at 37 degrees C. The glistenings were smallest in the 1-piece AcrySof IOLs (P <.001): 6.3 microm versus 11.5 microm in the Sensar and 13.4 microm in the 3-piece AcrySof. Upon cooling, the glistening quantity increased dramatically in the 1-piece AcrySof IOLs (P <.008) and was the highest among the IOL types at room temperature (P <.001). The mean glistening size was 7.7 microm. The 3-piece AcrySof IOLs showed a significant decrease in slitlamp-countable glistenings but acquired a dense haze seen as minute glistenings (4.0 microm) at x80 magnification. The glistening quantity in the Sensar IOLs was fairly stable upon cooling; a statistical increase was seen on the last day (P =.007). Cooling nearly doubled the size of the Sensar glistenings, which were the largest at room temperature, 21.7 microm (P <.001). CONCLUSIONS: Glistening quantity varied among hydrophobic acrylic IOLs and was temperature dependent. Sensar IOLs were more stable than the 2 other IOL types. The glistening phenomenon must be studied further to eliminate the problem.

Acrylic Resins↗