Craig Geist

Isolated oculomotor palsy following minor head trauma

A 54-year-old woman with an unremarkable medical history was in a minor motor vehicle collision resulting in airbag deployment. She reported loss of consciousness lasting a few seconds. She had no bruises or lacerations, but she immediately noted drooping of her left eyelid and double vision when she elevated the lid. She was taken to a local hospital, where she had an isolated, complete left oculomotor nerve palsy with a nonreactive pupil (figure). CT, MRI, and MR angiography were all normal (see figure E-1 on the Neurology Web site; go to www.neurology.org). Figure. Appearance of patient on initial presentation. Note complete third nerve palsy with pupil involvement. Over the next 6 weeks, the patient experienced mild improvement in ptosis, pupillary function, and ocular motility, but because of persistent diplopia and ptosis, she presented to the Wilmer Eye Clinic. On examination, the patient had normal visual sensory function, except for reduced accommodation on the left. The pupils were equal in size, but the left pupil was …

Does suture material and technique really matter? Lessons learned from 800 consecutive blepharoplasties.

Objectives: The purpose of this study was to evaluate established suture materials and techniques for blepharoplasty closure and evaluate for any differences in rates of complications between these groups.

Focused ultrasound facilitated thermo-chemotherapy for targeted retinoblastoma treatment: a modeling study

Retinoblastoma is the most common type of intraocular tumors in children. Currently, with early detection and improved systemic chemo-adjuvant therapies, treatment paradigm has shifted from survival to globe salvation/vision preservation. The objective of our work has been to explore the possible application of focused ultrasound (FUS) for targeted drug delivery in the posterior pole retinoblastoma. Specifically, theoretical models were implemented to evaluate the feasibility of using FUS to generate localized hyperthermia in retinal tumor areas, for potential triggering the chemotherapeutic agent deployment from heat-sensitive drug carriers. In-vitro experiments were conducted in tissue-mimicking phantoms with embedded excised rabbit eyes to validate the reliability of the modeling results. After confirming the reliability of our model, various FUS transducer parameters were investigated to induce maximal hyperthermia coverage in the tumor, while sparing adjacent eye structures (e.g. the lens). The evaluated FUS parameters included operating frequency, total acoustic power, geometric dimensions, transducer f-number, standoff distance, as well as different pulsing scenarios. Our modeling results suggest that the most suitable ultrasound frequency for this type of treatments was in the range of 2-3.5 MHz depending on the size of retinoblastoma. Appropriate transducer f-number (close to 1) and standoff distance could be selected to minimize the risks of over-heating undesired regions. With the total acoustic power of 0.4 W, 56.3% of the tumor was heated to hyperthermic temperature range (39-44 °C) while the temperature in lens was maintained below 41 °C. In conclusion, FUS-induced hyperthermia for targeted drug delivery may be a viable option in treatments of juxta-foveal or posterior pole retinoblastomas. Future in-vivo studies will allow us to determine the effectiveness and safety of the proposed approach.

A Study of Gulf War Veterans With a Possible Deployment-Related Syndrome

A previous symptom-based survey of veterans of the 1990-1991 Persian Gulf War suggested a neurological syndrome (blurred vision, loss of balance/dizziness, tremors/shaking, and speech difficulty). The authors conducted the present study to determine whether specific findings could indicate an organic basis for this possible syndrome. They completed an extensive clinical and laboratory evaluation on Gulf War veterans with all 4 symptoms, using 3 comparison groups. A single clinically based neurological syndrome could not be identified. No deployment-related exposure appeared to explain the pattern of symptoms, but this evaluation suggested comorbidities and possibly multiple vaccines as important contributors. Many of the neurological symptoms reported by the studied veterans appear to have an organic basis, but comorbidities must be excluded before researchers can conclude that a definitive syndrome exists.

Surface Acoustic Wave devices for ocular drug delivery

In this work we are reporting on the development of a novel Surface Acoustic Wave (SAW) device based on MEMS technology for drug delivery in the treatment of ocular diseases. The miniaturized SAW drug delivery device will be placed on the eye surface to allow non-invasive long-term drug application based on the programmed timeline and electronic control of a drug regiment. This novel drug delivery method is expected to lead to better clinical outcomes in the treatment of various eye diseases, and improved patient compliance with therapy. The device can be programmed for delivery of precise amounts of drugs at predetermined times over several months, and will use acoustic streaming to push the drug outside of the reservoir. Our modeling results were obtained using COMSOL multiphysics program and Coventor microfluidic simulator. Different force values were applied to investigate the force necessary to push the drug through the outlet.

A Review of “AMA Guides to the Evaluation of Ophthalmic Impairment and Disability: Measuring the Impact of Visual Impairment on Activities of Daily Life”

This book draws on concepts discussed in Guides to the Evaluation of Permanent Impairment, 6th edition (Chicago, AMA, 2008). It is designed to aid physicians in diagnosing visual impairment and disability. The book is easy to read and well detailed with illustrations, figures, and tables in each chapter. Chapter 1 provides an overview of concepts of impairment for all organ systems and what this means for body function, activity, and participation. The model of the International Classification of Functioning (ICF) is discussed. Terminology and areas of personal function in the context of activities of daily living (ADLs) are detailed. Functional assessment and calculation of impairment are described. Chapter 2 provides very clear definitions and distinctions between disability and impairment and a discussion of the limitations of these determinations. This is particularly evident when applied to the individual and his/her ability to cope with daily life and work when other influences such as motivation, technology, and accommodative measures are factored in. Specific ophthalmic terminology is reviewed, including definitions of visual impairment and visual function. Measurements of visual function and calculations are discussed for functional visual score (FVS), functional acuity score (FAS), and functional field score (FFS). This is the true core of the book and these values may at times seem difficult to determine. I believe that this chapter would benefit from the use of more examples on calculation of specific impairment scores. Chapter 3 discusses visual function, the visual tasks of many areas of employment, and determination of accommodation for an employee to perform a job if impairment exists. As the book notes, an analysis of visual tasks and the standardization of visual testing should be employed to meet requirements set by the American Disabilities Act (ADA). Chapter 4 demonstrates how to perform eye-screening tests to evaluate visual performance. This is a “how to” section, which utilizes various visual function tests to identify defects. It is an oversight in the book that there is no mention in the book about standardization of equipment and, in particular, lighting standards for some of these tests. For example, in color vision testing, the MacBeth-Easel lamp has been recommended but is now unavailable. Studies have shown the Verilux True Color Light is just as effective. These visual function tests may identify defects but are not utilized to diagnose and qualitate. Significant documented defects, as mentioned in the book, require referral to an ophthalmologist for evaluation. Chapter 5 discusses the disability: a measurement of health and disability at the individual and population levels, as well as the enabling and disabling processes. Various factors and the ultimate effect on quality of life are considered. The employer may and should look at what a patient can do and not simply what they cannot do. Compensation and benefits are covered as well. An overview of ranges of visual function classification is provided and visual rehabilitation is discussed. There are four Appendices in this edition. They are devoted to further details on eye physiology, definitions of eye disorders, various testing methods for vision, as well as vision standards for various professions and more detail on the Americans with Disabilities Act. In general, this is a thorough guide to the estimation of visual impairment and also the whole-body impairment of the patient. Impairment and disability are complex concepts and Dr Blais has done a great job incorporating the literature, background, and overviews to frame these conditions. As mentioned previously, the practical aspect of this handbook could be improved. There should be more examples on calculations of visual scores and impairment percentages. This could be incorporated into an appendix in which cases were described and the calculations of FFS are shown for various visual field defects using either automated static or kinetic perimetry.