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Kevin M Miller

Publications and source records attributed to Kevin M Miller.

14 recordsLinked to original sources
PubMed2006

External dosimetry in the aftermath of a radiological terrorist event.

This paper reviews external dosimetry in emergency preparedness planning for a potential terrorist release of radioactive material in a densely populated area. The radiation dose received by response workers and members of the public is needed to understand health risks. The existing framework for dosimetry of routinely occupationally exposed workers is not directly applicable to all emergency workers who would respond to a radiological terrorist event. Emergency preparedness plans incorporate various old and new dosimetry technologies, including quartz fibre electrets, electronic dosemeters, personnel badges and wallet cards. Environmental monitoring and dose calculations are the usual methods for determining public dose. However, during the late-phase response, after removable contamination has been eliminated, it may be easier and more straightforward to provide individual dosimetry for members of the public who may be moving through a city with varying contamination areas. Doing so could allow resumption of normal activities earlier and promote confidence in reusing the site.

Disaster Planning↗
PubMed2006

Implanting a clear intraocular lens in one eye and a yellow lens in the other eye: a case series.

PURPOSE: To describe the color vision disturbance reported by patients in whom a clear intraocular lens (IOL) was implanted in one eye and a yellow-tinted (blue-light-absorbing) IOL in the other eye. DESIGN: Retrospective interventional case series. METHODS: Data recorded included demographic information, dates of surgery, IOL model and power (manufacturer is the same for all lenses), best-corrected visual acuity, and subjective visual complaints. RESULTS: Four of five patients had no spontaneous color vision complaints. When these patients were informed of the unintended mismatch, all remarked that they could perceive a color vision difference, but that it was not bothersome. One of the five patients reported "beige" vision. None of the patients wanted an IOL exchange. CONCLUSION: Many patients can tolerate the color vision imbalance that results when a clear IOL is implanted in one eye and a yellow-tinted IOL is implanted in the other eye.

Aged↗
PubMed2005

Preliminary efficacy and safety of zero diopter lens implantation in highly myopic eyes.

PURPOSE: To report the preliminary efficacy and safety of zero diopter (D) intraocular lens implantation in highly myopic eyes. DESIGN: Retrospective surgical case series. METHODS: Three highly myopic eyes with axial lengths greater than 30 mm were implanted with zero D Alcon model MA60MA 3-piece acrylic posterior chamber lenses at the time of cataract surgery. RESULTS: Uncorrected visual acuity improved from counting fingers to 20/20- and 20/40- in two eyes. Best-corrected visual acuity improved from 20/80 and 20/60+ to 20/20- in the same eyes. A third eye was at counting fingers before and after surgery, because of a staphyloma. The range of preoperative, intended postoperative, and achieved postoperative spherical equivalent refractive errors was -15.1 to -25.0 diopters, -0.20 to -1.44 diopters, and +0.13 to +0.50 diopters respectively. CONCLUSIONS: All eyes experienced mild hyperopic refractive errors after surgery. No retinal detachments occurred during the follow-up interval.

Acrylic Resins↗
PubMed2005

Explantation of an AcrySof Natural intraocular lens because of a color vision disturbance.

PURPOSE: To describe a patient who complained of color vision disturbance after implantation of a clear intraocular lens (IOL) in one eye and a yellow IOL in the other. DESIGN: Interventional case report. METHODS: A 50-year-old woman complained of binocular imbalance and "yellow vision" in her left eye after implantation of a visible blue light-filtering yellow IOL. A clear IOL had been implanted in her right eye 1 month before. She requested explantation of the yellow IOL. RESULTS: The yellow IOL was exchanged for a clear one, which resolved the unbalanced color vision. CONCLUSIONS: Patients may be intolerant of the color disturbance that results when dissimilarly colored IOLs are implanted. It is advisable to avoid this practice.

Acrylic Resins↗
PubMed2005

In-air thermal imaging comparison of Legacy AdvanTec, Millennium, and Sovereign WhiteStar phacoemulsification systems.

PURPOSE: To compare the temperature profiles of 3 popular phacoemulsification units (Alcon Legacy AdvanTec, Bausch & Lomb Millennium, and AMO Sovereign WhiteStar) under similar operating conditions in air. SETTING: Jules Stein Eye Institute and the Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, California, USA. METHODS: Phacoemulsification probes from the 3 units were placed side by side in air and imaged in the infrared region using model P60 ThermaCAM (Flir Systems). The highest temperature produced by each probe was measured 10 seconds and 30 seconds after power application. Testing was performed under conditions that might produce a corneal burn during cataract surgery. Irrigation flow was set at the low rate of 1 cc/min to simulate a tight incision. Aspiration flow was set at 0 cc/min to simulate occlusion of the needle lumen. Wound compression was simulated in some tests by suspending 22.6 g weights by rubber bands from the silicone sleeves. Manufacturers' specific and identical silicone sleeves were used to evaluate possible variations in thermal conductivity. The AdvanTec Legacy and Millennium were operated in pulse mode at 15 Hertz; 50% duty cycle; and 10%, 30%, and 50% power. The Sovereign WhiteStar was operated in both C/F (56 Hz, 33% duty cycle) and C/L (33 Hz, 20% duty cycle) modes at the same console power settings. Temperature profiles were determined at a variety of power settings with each system operating in continuous and pulse mode. RESULTS: Under all experimental conditions (at 10%, 30%, and 50% powers; with and without external weights suspended from the phacoemulsification probes; with manufacturers' and identical silicone sleeves; and in continuous and pulse modes), the Millennium and the Sovereign WhiteStar generated higher temperatures than the Legacy AdvanTec. CONCLUSIONS: Under controlled operating conditions in air and under a variety of power, load, and duty-cycle settings, the Millennium and the Sovereign WhiteStar, operating in both pulse and continuous modes, generated higher peak temperatures than the Legacy AdvanTec.

Air↗
PubMed2005

Pillow case.

An 80-year-old man with severe kyphosis and visually significant cataracts in both eyes came to us for care. He had been scheduled for cataract surgery elsewhere, but his surgery was cancelled in the operating room when he could not be positioned adequately beneath the operating microscope. As he sat in a chair in our examining room, he was only able to elevate his head to a position 30 degrees below the horizontal. His cataract surgery was performed safely and effectively by padding the operating table with 14 pillows. Eleven pillows were placed under his buttocks and legs and 3 pillows beneath his head and neck. The operating table was also positioned in maximum reverse Trendelenburg to obtain a good red reflex.

Aged, 80 and over↗
PubMed2005

Interim results of the United States investigational device study of the Ophtec capsular tension ring.

PURPOSE: To evaluate the safety and efficacy of the Ophtec capsular tension ring (CTR) in providing capsular support during and/or after cataract extraction in cases of a weak or partially broken ciliary zonule. DESIGN: Phase III multicenter, nonrandomized, investigational device study. PARTICIPANTS: Twelve investigators at 9 sites enrolled 224 subjects and placed 255 CTRs. METHODS: Capsular tension rings were placed in patients who were found to have a weakened or partially broken ciliary zonule comprising <34% of the circumference of the lens capsule. Two CTR models were evaluated, with noncompressed diameters of 12 mm and 13 mm. Patients were examined preoperatively, intraoperatively, and postoperatively at day 1 and months 1, 3, 6, and 12. MAIN OUTCOME MEASURES: Rate of successful stabilization of the capsular bag and intraocular lens (IOL) centration, complications, and adverse events. RESULTS: Interim results from this ongoing study indicate that immediately after surgery 98.8% of IOLs were centered and 1.2% of the IOLs implanted (3/251) were not centered. Subsequently, the prevalence of decentered IOLs was 1.7% (4/236) 3 months after surgery, 3.8% (8/211) 6 months after surgery, and 2.3% (4/172) 12 months after surgery. The primary complication was posterior capsular opacification, which is unlikely to be a complication of CTR insertion. Neodymium:yttrium-aluminum-garnet laser capsulotomies have been performed in 12.8% of eyes by 12 months (22/172). CONCLUSIONS: Ophtec CTR models 275 and 276 safely provided capsular support during and after cataract surgery in cases where the zonule was weak or partially broken.

Adult↗
PubMed2004

Functional visual outcomes of cataract extraction in monocular versus binocular patients.

PURPOSE: To determine the change in functional vision that occurs with cataract surgery in a group of monocular patients compared with a group of binocularly sighted control subjects. DESIGN: A retrospective case-control study. METHODS: Study subjects comprised 100 functionally monocular patients who underwent cataract surgery at the Jules Stein Eye Institute between 1996 and 2002. Control subjects were 100 binocularly sighted patients, matched to study subjects by age, sex, and timing of surgery. A single ophthalmologist performed all of the operations using an ultrasonic phacoemulsification technique. Best-corrected visual acuity (BCVA) was measured before and after surgery using a conventional visual acuity monitor. Self-reported visual function was assessed before and after surgery using the Visual Function 14 (VF-14) questionnaire. Paired t tests were used to report statistical significance. RESULTS: The monocular group had significantly worse mean BCVA than the binocular group before and after surgery, but the improvement experienced by the two groups was statistically indistinguishable (P =.913). Mean global VF-14 score was significantly worse for the monocular than the binocular group before and after surgery, but the monocular group experienced a significantly greater improvement (P =.00164) in VF-14 following surgery (20.4 points for the monocular group vs 10.1 points for the binocular group). CONCLUSIONS: Monocular patients report twice as much improvement in functional vision as binocular patients despite similar BCVA gains. This may be because monocular patients had cataract surgery on their better-seeing eye, whereas binocular patients typically had surgery on their poorer-seeing eye.

Adult↗
PubMed2004

Ophtec iris reconstruction lens United States clinical trial phase I.

PURPOSE: To determine the safety and efficacy of the Ophtec model 311 iris reconstruction lens for treatment of visual disturbances, such as glare or photophobia, related to partial or total absence of the human iris. DESIGN: Phase I multicenter, nonrandomized, investigational device study. PARTICIPANTS: Ten iris reconstruction lenses were placed in 10 subjects at 6 sites. METHODS: Iris reconstruction lenses were placed in 9 patients who had lost all or part of their iris from trauma and in 1 patient who lacked iris pigmentation due to congenital albinism. Patients were examined preoperatively, intraoperatively, and postoperatively at day 1; week 1; and months 1, 3, 6, and 12. MAIN OUTCOME MEASURES: Efficacy measures were uncorrected visual acuity (UCVA), glare, starbursts, and photophobia. Safety measures were best-corrected visual acuity (VA), surgical complications, and adverse events. RESULTS: Uncorrected VA improved in all eyes after implantation of the iris reconstruction lens. Best-corrected VA did not change significantly (P = 0.24). Postoperative photophobia was reduced in all 9 eyes that experienced moderate to severe preoperative photophobia. Likewise, postoperative glare was reduced in all 6 eyes with moderate to severe preoperative glare. There were no surgical complications. Adverse events included 2 cases of iritis and 1 case of macular edema. CONCLUSIONS: Preliminary results suggest that the Ophtec model 311 iris reconstruction lens can improve UCVA and reduce glare and photophobia in patients with partial or total absence of the iris or iris pigmentation.

Adult↗
PubMed2002

1,6-methano[10]annulene-stabilized radicals.

The rate of the methylenecyclopropane rearrangement is remarkably enhanced by the 1,6-methano[10]annulene group, which greatly stabilizes the biradical intermediate. The diastereomeric products argue against a concerted rearrangement mechanism and support a stabilized biradical intermediate that lives long enough to undergo rotation before ring closure. [structure: see text]

Journal Article↗
PubMed2002

Outcomes of cataract extraction in functionally monocular patients. Case-control study.

PURPOSE: To compare the ocular comorbidities, visual outcomes, and surgical complications between a series of functionally monocular patients who had phacoemulsification and intraocular lens (IOL) implantation and a control group of age- and sex-matched binocular patients. SETTING: Jules Stein Eye Institute and the Department of Ophthalmology, UCLA School of Medicine, Los Angeles, California, USA. METHODS: The records of a consecutive series of 100 functionally monocular patients who had phacoemulsification and IOL implantation were reviewed. The records of a control group of binocularly sighted patients who were matched to the monocular patients by age, sex, and date of surgery were also reviewed. RESULTS: Thirteen patients in the monocular group were monocular because of surgical complications. The remaining patients (87%) were monocular from medical conditions. Monocular patients had significantly more ocular comorbidity than binocular control patients (P <.0001). Age-related macular degeneration, diabetic retinopathy, and open-angle glaucoma were the most common reasons for monocular status and the most common ocular comorbidities in study eyes. The median preoperative best corrected visual acuity (BCVA) was 20/50 in the monocular group and 20/40 in the binocular group. The median postoperative BCVA was 20/25 and 20/20, respectively. A final BCVA of 20/40 or worse was the result of preexisting macular pathology or glaucoma in every instance. Surgical complications (P =.096) and the number of postoperative procedures (P =.724) were similar between the 2 groups. CONCLUSIONS: Ocular comorbidity was significantly more prevalent in the eyes of monocular patients. Monocular and binocular patients experienced a 3-line improvement in BCVA after cataract surgery; however, the final median acuity was 20/25 in the monocular group and 20/20 in the binocular group. The 2 groups had a similar complication rate.

Case-Control Studies↗
PubMed2002

The development of field-based measurement methods for radioactive fallout assessment.

An overview is provided on the development of field equipment, instrument systems, and methods of analyses that were used to assess the impact of radioactive fallout from atmospheric weapons tests. Included in this review are developments in fallout collection, aerosols measurements in surface air, and high-altitude sampling with aircraft and balloons. In addition, developments in radiation measurements are covered in such areas as survey and monitoring instruments, in situ gamma-ray spectrometry, and aerial measurement systems. The history of these developments and the interplay with the general advances in the field of radiation and radioactivity metrology are highlighted. An emphasis is given as to how the modifications and improvements in the instruments and methods over time led to their adaptation to present-day applications to radiation and radioactivity measurements.

History, 20th Century↗
PubMed2002

Decreased expression of ribosomal proteins in human age-related cataract.

PURPOSE: To identify lens epithelial genes with altered expression levels in age-related human cataract. METHODS: Epithelia from age-related cataracts and from normal lenses were microdissected and RNA was extracted. RNAs were compared for gene expression differences by RT-PCR differential display. Transcripts exhibiting altered levels of gene expression were cloned and identified by sequencing. The expression levels of identified clones were confirmed by semiquantitative RT-PCR with three separately isolated RNA preparations. Specific primers were designed and used to examine the mRNA levels of other genes important in protein synthesis. RESULTS: Numerous transcripts exhibited altered levels of gene expression. One transcript exhibiting a decreased level of expression in cataract compared with normal lenses was identified as encoding ribosomal protein L21. Three additional ribosomal proteins, L15, L13a, and L7a, also exhibited decreased expression in cataract compared with normal human lenses. By contrast, the levels of elongation factor (EF)-1alpha1 and eucaryotic initiation factor (eIF)-4E remained unchanged. CONCLUSIONS: The results provide evidence that human age-related cataract is associated with decreased expression of L21 and other ribosomal proteins. The results suggest that modulation of protein synthesis and/or other functions mediated by ribosomal proteins is associated with age-related cataract.

Aged↗