Mouse Model Shows Gene Therapy Can Reverse Blue Cone Vision Disorder

MedicalResearch.com Interview with:

Wen-Tao Deng,

Dr. Wen-Tao Deng

Wen-Tao Deng, Ph.D.
Department of Ophthalmology, College of Medicine|
University of Florida, Gainesville, FL

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Blue cone monochromay (BCM) is a devastating vision disorder characterized by loss function of both L- and M-cones due to mutations in the L- and M-opin gene cluster on the X chromosome. BCM patients display severely reduced visual acuity, loss of color-vision, myopia, nystagmus, and minimally detectable cone-mediated electroretinogram. In our studies, we showed that an M-opsin knockout mouse model resembles human BCM, and expression of either human M- or L-opsin individually or combined through adeno-associated viral vector promotes regrowth of cone outer segments and rescues M-cone function in the treated M-opsin dorsal retin

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Optic Nerve Stroke: Bone Marrow Stem Cells Offer Hope of Vision Improvement

MedicalResearch.com Interview with:
Steven Levy MD

CEO, MD Stem Cells
Study Director, Stem Cell Treatment Studies

MedicalResearch.com: What is the background for this study?

Response: MD Stem Cells is the sponsor of the Stem Cell Ophthalmology Treatment Study II (SCOTS 2) the largest stem cell study currently addressing retinal and optic nerve disease (NCT 03011541). SCOTS uses autologous bone marrow derived stem cells (BMSC) typically provided to the eyes by combining retrobulbar, subtenons and intravenous injections. Many retinal and optic nerve diseases are eligible including Retinitis Pigmentosa (RP), Age Related Macular Degeneration (AMD), Stargardts, Ushers, Glaucoma, Ischemic Optic Neuropathy, Optic Atrophy and others. Statistically significant improvements have been documented in key diseases and positive responses have been noted across most conditions treated. Mechanisms of action may include differentiation of the CD34 cells into neurons, secretion of neurotrophic factors, transfer of mitochondria and release of mRNA. These may benefit existing stressed cells as well as provide replacement of damaged or absent cells.

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Single-Dose LipiFlow® Treatment Relieves Dry Eye Symptoms

MedicalResearch.com Interview with:

Dr. Caroline A. Blackie, OD PhD FAAO Medical Director, Dry Eye Johnson & Johnson Vision

Dr. Caroline Blackie

Dr. Caroline A. Blackie, OD PhD FAAO
Medical Director, Dry Eye
Johnson & Johnson Vision

MedicalResearch.com: What is the background for these studies? Would you briefly explain the problem of dry eye, how common it is and why it is difficult to treat? 

Response: Dry eye disease is a condition where the eyelids and/or the tear film are unable to protect the ocular surface from the negative effects of desiccating stress. If left untreated, a vicious cycle ensues resulting in a broad spectrum of sequelae, including ocular discomfort and compromised vision. The result is partial or pervasive reduced quality of life for the individual along with a significant economic burden on our society. Conversely, when the ocular surface is healthy, patients feel better, see better and live better.

Meibomian gland health is essential for ocular surface health. Meibomian glands secrete the oils necessary to protect the ocular surface from the negative effects of desiccating stress. Predictably, meibomian gland dysfunction (MGD) is a leading cause of dry eye disease. MGD is almost always the result of thickened and stagnated gland secretions. These stagnated secretions obstruct and/or limit the flow of functional oil into the tear film. MGD is the most common form of dry eye disease and is also known as evaporative dry eye. While management of dry eye in general can be complex, the management of MGD affords a relatively straightforward approach, which is to improve meibomian gland function by treating obstruction.

Dry eye disease is pretty common – more than 340 million people suffer from it globally. Short-term management of dry eye involves improving signs and symptoms of the condition, including the use of tear supplementation and reducing ocular surface inflammation.

Long-term dry eye management requires that the cause (or causes) of the condition is also diagnosed and treated. That cause is often MGD, and MGD can be successfully managed with LipiFlow®.  Continue reading

Ophthalmology Consultation for Emergency Care at a University Hospital

MedicalResearch.com Interview with:

Maria A. Woodward, MD, MSc Department of Ophthalmology and Visual Sciences W. K. Kellogg Eye Center Institute for Healthcare Policy and Innovation University of Michigan Ann Arbor, MI

Dr. Woodward

Maria A. Woodward, MD, MSc
Department of Ophthalmology and Visual Sciences
W. K. Kellogg Eye Center
Institute for Healthcare Policy and Innovation
University of Michigan
Ann Arbor, MI

MedicalResearch.com: What is the background for this study? What are the main findings? 

Response: Many people go to emergency departments seeking care for their eye problems. We wished to investigate which factors are associated with the involvement of ophthalmologist consultants in the care of these patients and whether any disparities exist.  Continue reading

Oral vs IV Steroids for Acute Optic Neuritis

MedicalResearch.com Interview with:

Sarah A. Morrow MD, MS, FRCPC Associate Professor of Neurology Department of Clinical Neurological Sciences University of Western Ontario (Western)

Dr. Morrow

Sarah A. Morrow MD, MS, FRCPC
Associate Professor of Neurology
Department of Clinical Neurological Sciences
University of Western Ontario (Western)

MedicalResearch.com: What is the background for this study?

Response: Acute demyelinating optic neuritis, which presents with loss of vision and painful eye movements, is common in multiple sclerosis (MS) occurring 50% of persons with MS. High dose (≥ 1g) corticosteroids administered through an IV became the standard of practice after the landmark Optic Neuritis Treatment Trial as IV administration. However, in that study the IV dose of corticosteroids was much higher (1 gram daily) than the oral dose (1 mg/kg). Thus, it is not clear if IV administration is still better if equivalent doses are used orally. Oral administration is much more convenient for patients and less expensive, and previous studies showed that it is preferred by patients.

In this study, we asked the following question: are high dose (≥ 1000mg) IV corticosteroids superior to equivalent doses of oral corticosteroids for the acute treatment of optic neuritis?

We randomly assigned fifty-five cases of acute optic neuritis to 1000mg IV methylprednisolone or 1250mg oral prednisone daily for three days and compared recovery of their vision over the next 6 months.  Continue reading

Genetic Link Between Corneal Thickness and Risk of Glaucoma

MedicalResearch.com Interview with:

Eldon E. Geisert, PhD Professor of Ophthalmology Emory School of Medicine

Dr. Geisert

Eldon E. Geisert, PhD
Professor of Ophthalmology
Emory School of Medicine

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: In the late 1990s a group of doctors began a study of glaucoma patients to determine if there were phenotypes that are predictive for developing glaucoma.

In this Ocular Hypertension Treatment Study (OHTS) one of the highly correlated ocular traits was central corneal thickness (CCT). The early clinical studies found that people with thinner corneas were at a higher risk of developing glaucoma. In two large studies, examining thousands of people a number of genes were identified that were risk factors for glaucoma or that controlled CCT in humans. In both cases the identified genes accounted for less than 10% of the genetic risk for glaucoma and less than for 10% of the genetic control for CCT. There was little data linking the genetic control of CCT to the glaucoma risk.

Our group has taken an indirect approach to the question, using well-defined mouse genetic system to identify genes modulating CCT and then interrogating human glaucoma data to determine if these genes are associated with glaucoma risk.   Continue reading

Unnecessary Routine Preoperative Cataract Testing Costs Medicare Millions

MedicalResearch.com Interview with:
Catherine L. Chen, MD, MPH

Assistant Professor
UCSF Department of Anesthesia & Perioperative Care

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Routine preoperative medical testing (such as common laboratory tests looking at a patient’s blood cell counts and kidney function, or cardiac tests like an EKG) are not recommended in patients undergoing cataract surgery, but these tests still occur quite frequently among Medicare cataract surgery patients because these patients tend to be older and sicker than the general population. In the past, researchers have used a 30-day window counting backwards from the date of surgery to determine whether a given test should be categorized as a routine preoperative test. However, we know that testing often takes place outside this window and therefore, the frequency and cost of routine preoperative medical testing has generally been underreported.

In our study, we used a new method to figure out how to determine the start of the routine preoperative testing period. In cataract patients, ocular biometry is a diagnostic test that is performed in anticipation of cataract surgery, and this test is only performed in cataract patients who will be having cataract surgery in the near future. For each patient, we calculated the elapsed time between the ocular biometry and cataract surgery dates to get a better idea of when to start looking for unnecessary routine preoperative testing. Our goal was to identify all the routine preoperative medical testing that occurs once the decision has been made to operate and better estimate the cost to Medicare of this unnecessary testing.

In a previous study that we published in the New England Journal of Medicine, we reported a significant spike in the rate of routine preoperative medical testing that occurs in the 30 days before surgery compared to the baseline rate of testing. In our current study, we discovered that there is a second spike in testing that occurs in the 30 days after ocular biometry. In fact, even if you exclude the testing that takes place during the 30 days before surgery, there is still a 41% increase in testing rates during the interval between ocular biometry and cataract surgery over the baseline rate of testing. In addition, we found that the cost of routine preoperative testing was 47% higher when looking at the entire biometry to surgery timeframe compared to testing that occurs just in the 30 days before surgery.

We estimate that the cost to Medicare of all of this unnecessary testing approaches $45.4 million annually. Continue reading

Tunable Lens Allows Detailed Imaging of Entire Eye

MedicalResearch.com Interview with:

Ireneusz Grulkowski, PhD Assistant Professor Bio-Optics & Optical Engineering Lab Institute of Physics Nicolaus Copernicus University

Dr. Grulkowski

Ireneusz Grulkowski, PhD
Assistant Professor
Bio-Optics & Optical Engineering Lab
Institute of Physics
Nicolaus Copernicus University

MedicalResearch.com: What is the background for this study?

Response: The ophthalmic diagnostics has undergone a revolution over the last 30 years. The access to new modalities allowed to understand the process of development of different eye diseases of the retina and the anterior segment. In particular, optical coherence tomography (OCT) demonstrated the feasibility in visualization of microarchitecture of the ocular tissues. However, most of the ophthalmic equipment is dedicated either to imaging the anterior segment of the eye (e.g. the cornea) or to retinal imaging. This is due to the fact that the eye is composed of the elements, such as the cornea and the lens, that refract the light.

In this report, we wanted to address that challenge. We compensated the refractive power of the eye by the application of the tunable lens. The focus tunable lens is the example of active optical element that changes its focal distance with the applied electric current.

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LUXTURNA Proves Effectiveness of Single Gene Therapy To Cure Rare Cause of Blindness

MedicalResearch.com Interview with:

Dr. Stephen M. Rose, PhD Chief Research Officer Foundation Fighting Blindness

Foundation Fighting Blindness

Dr. Stephen Rose PhD
Chief Research Officer
Foundation Fighting Blindness (FFB)

Dr. Rose comments on the announcement of the FDA approval of voretigene neparvovec (LUXTURNA™) gene therapy for inherited blindness due to mutations in the RPE65 gene.

What is the background for this announcement? What were the main findings from the study?

Response: While it has been 30 years since the RPE65 gene was identified as causing Leber’s Congenital Amaurosis, this shows that it is possible to have an effective gene therapy for an inherited disease. As the first gene therapy for the eye or for an inherited disease, LUXTURNA is a historic milestone in the search for cures for all inherited retinal diseases (IRDs). As a one-time gene therapy, LUXTURNA will not only be life-changing for patients with vision loss due to mutations in the RPE65 gene, it also provides critical momentum for gene therapies – for the eye and other diseases – now in the clinic.  Continue reading

Retinopathy in Premature Infants: Low Dose Ranibizumab May Be Effective Without Systemic Side Effects

MedicalResearch.com Interview with:

Prof. Dr. Andreas Stahl
Geschäftsführender Oberarzt
Leiter Arbeitsgruppe Angiogenese
Universitätsaugenklinik Freiburg | University Eye Hospital Freiburg
Freiburg, Germany

MedicalResearch.com: What is the background for this study?

Response: Retinopathy of prematurity (ROP) is a sight-threatening disease and one of the main reasons for irrreversible bilateral blindness in children. Particularly infants born at very early gestational ages or with very low birth weight are affected. In these infants, vascularization of the retina is unfinished at the time of birth. Severeal weeks into the life of these very prematuerly born infants, angiogenic growth factors, mainly vascular endothelial growth factor (VEGF), become upregulated in the avascular parts of the retina, leading to a re-activation of physiologic vascular growth. If all goes well, these re-activated retinal blood vessels progress towards the periphery and lead to a fully vascularized and functional retina. If, however, the vascular activation by VEGF is too strong, then vascular growth becomes disorganized and vessels are redirected away from the retina and into the vitreous. If left untreated, these eyes can then proceed towards tractional retinal detachment and blindness.

Since the 1990s, the standard method of treating ROP has been laser photocoagulation of avascular parts of the retina. This treatment is sensible because VEGF as the main angiogenic driver of pathologic blood vessel growth is expressed in these avascular parts of the retina. The downside of laser treatment, however, is that treated retinal areas are turned into functionless scar tissue and are lost for visual function. In addition, infants treated with laser need to be under general anesthesia for hours during treatment which can be troublesome in very young and fragile preterm infants. And in the long run, infants treated with laser have a high risk of developing high myopia in later life.

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