The abstract reports that:

Mean follow-up was 10.69±5.95 months (range: 3 to 16 months). Mean preoperative spherical equivalent refraction (SE) was –3.03±3.23 diopters (D) and defocus was 4.67±3.29 D; at last follow-up SE and defocus were statistically significantly reduced to –1.29±2.05 D and 3.04±2.53 D, respectively (P<.01). Preoperative mean (logMAR) uncorrected visual acuity was 0.99±0.81 and best spectacle-corrected visual acuity was 0.21±0.19, which improved postoperatively to 0.16±0.15 and 0.11±0.15, respectively. The mean steepest keratometry was reduced from 48.20±3.40 D preoperatively to 45.13±1.80 D at last follow-up. 

Based on these results, researchers concluded that “[s]imultaneous PRK followed by CXL seems to be a promising treatment capable of offering functional vision in patients with keratoconus.”

For access to the abstract and full text of the article, go here (subscription required for full text).

The study by the BU School of Medicine and the VA Boston is not part of the CATT Study, but is a randomized double-blind study of the two drugs for treating AMD. According to the abstract and the news release, there was no difference in effectiveness after six months.

Source: Science Codex

Here’s the link to the writeup in my online Journal

Five risk factors were determined in a study in 1995 — thickness greater than 2 mm, subretinal fluid, symptoms, orange pigment, and margin near the optic disc (Shields CL et al. Arch Ophthalmol. 2000;118(3):360-364.) The use of these factors has been helpful in early detention of choroidal melanoma. In this analysis, the researchers looked to further identify these risk factors in a larger group of study subjects.

The records of 2514 eyes with choroidal nevi were retrospectively reviewed; each of these patients had been evaluated with indirect ophthalmoscopy and high-resolution magnification of the nevi itself when possible. The authors found that the median tumor basal diameter was 5.0 mm and thickness was 1.5 mm in the study subjects. Nevus growth into melanoma occurred in 2%, 9%, and 13% of eyes at 1, 5, and 10 years, respectively.

After multivariate analysis, the significant predictors of transformation into melanoma were:

• Tumor thickness >2 mm (P<0.001)
• Subretinal fluid (P=0.002)
• Symptoms, such as decreased vision or flashes (P=0.002)
• Orange pigment (P<0.001)
• Tumor margin within 3 mm of the optic disc (P=0.001)
• Ultrasonographic hollowness (P<0.001)
• Absence of halo (P=0.009)

There is also a mnemonic device to remember these characteristics: “To find small ocular melanoma using helpful hints.” This represents thickness, fluid, symptoms, orange pigment, margin, ultrasonographic hollowness, and halo absence. The median hazard ratio (HR) for the growth of a nevus into melanoma with 1 or 2 risk factors was 3; for those nevi with 3 or 4 factors, the HR was 5; for 5 to 6 factors, the HR was 9; and for all 7 factors, the HR was 21.

The use of this predictor can help ophthalmologists identify those people that are at risk for transformation as noted by the study authors.

Read the article.

The researchers first studied the effects of the NGF drops in a rat model of glaucoma and found that 200 µg/mL of NGF was effective in preventing retinal cell death—more so than a 100 µg/mL dose. Three patients with progressive visual field defects despite IOP control were also treated with NGF eye drops; these patients underwent electrofunctional tests at baseline, after 3 months of NGF eye drops and after follow up.

The researchers found that there was significantly less retinal ganglion cell loss with NGF treatment. The patients treated with NGF showed improvements in visual field, optic nerve function, visual acuity and contrast sensitivity.

This is a very interesting finding because these eye drops may open up a new avenue of treatment for patients with glaucoma and other neurodegenerative diseases. Neuroprotection has been a new and active area of interest in the treatment of glaucoma; obviously there needs to be more research but these results are encouraging.

Read the abstract here.

Prototype contact lenses of PLGA (poly[lactic-co-glycolic acid]) films coated with pHEMA (poly[hydroxyethyl methacrylate]) contained  encapsulated fluorescein or ciprofloxacin. Ciprofloxacin released from the contact lens was evaluated in an antimicrobial assay to verify its antimicrobial effectiveness.

After an initial burst, the prototype lens demonstrated a sustained release of either substance for up to four weeks. The rate of release could be controlled by altering ratios of drug or mass of PLGA used. The ciprofloxacin was active against ciprofloxacin-sensitive Staphylococcus aureus at each time tested.

This concept of drug-dosed contact lenses has been discussed and attempted before. It will be interesting to see if this particular concept is more successful; it could be very helpful for corneal ulcers or glaucoma. It could eliminate some concerns about patient compliance in these diseases.

Read the abstract and article here (log in required).

The report relied on a retrospective study of Part B Medicare data for 100,000 beneficiaries from 1997 to 2006. Researchers found the most common surgical treatments for glaucoma include laser trabeculoplasty, filtering surgery, tube shunt surgery and cyclodestructive procedures.

Overall, there were decreases noted in both the number of glaucoma surgical procedures and the amount of annual Medicare payments from 1997 to 2001, but there was an increase in the number of procedures in the following years. In particular, after an initial decline, the number of trabeculoplasties increased. However, Medicare payments for trabeculectomies decreased over time, while annual payments for newer procedures, such as cyclophotocoagulation and shunt-related procedures, increased.

Limitations on the studies include that it examined only fees paid directly to physicians, and of course, does not include data on patients between 40 to 64 who are not covered by Medicare.

This study brings up several interesting, thought-provoking points: why is there a trend for more trabeculoplasties? How will this trend impact national glaucoma expenditures? With the changes in health care that are being discussed, these types of questions should be looked at by ophthalmologists so we can participate in the discussion and continue to provide quality care for our patients.

Read the abstract and full article here (log in required).

In the July 2009 issue of the journal Diabetes, researchers report that the transforming growth factor (TGF)-ß pathway is a target for possible drug therapies to prevent the destruction of capillaries in diabetic retinopathy.

The authors examined the gene expression profile of the retinal vessels from rats with streptozotocin-induced diabetes then tested whether sorbinil and aspirin stopped some of the common molecular abnormalities caused by diabetes.  The retinal vessels in the diabetic rats showed differential expression of 20 genes in the TGF-ß pathway and the complete loop of the TGF- ß pathway was enhanced in the retinal vessels.  Sorbinil influenced the expression of genes related to both oxidative stress and to inflammation; both drugs were concordant in upregulating genes in the TGF- ß pathway.

While basic science research is miles away from being clinically useful, finding the basic puzzle pieces to the diabetic retinopathy opens new avenues for research for the treatment of DR before vision loss occurs. While many of the drugs to treat DR at early stages have not been very successful thus far, it doesn’t mean the research should stop – perhaps the facts that we are learning now can be combined with what we know and what failed in the past to come up with a treatment.

Read the abstract and full-text article here (login required) in Diabetes: A Journal of the American Diabetes Association.

K5 nanoparticles (K5-NP) were created and used to induce expression of K5 in rats with streptozotocin-induced diabetes; the possible side effects of the nanoparticles were measured as well. The researchers found that the levels of K5 were effectively mediated by the K5-NP and specifically inhibited the development of endothelial cells. Injection of the K5-NP significantly reduced the retinal vascular leakage and retinal neovascularization in the diabetic rats. No toxicities were noted during this study.

More details about K5 are needed but this offers another avenue for study and hope for the patients with diabetes and those clinicians that treat the condition.

Read the abstract and full-text article here (login required) in Diabetes: A Journal of the American Diabetes Association.

This was a prospective, open-label study with 139 enrollees who had either ocular hypertension or glaucoma. The patients answered questions about their eye drops usage, and a video was created to document the patient’s administration of eye drops with two different types of eye drop bottles.  Only about twenty-one percent of the participants were able to successfully place the eye drops without touching the eye structures with a 15 mL bottle and almost thirty percent were able to do so with a 2.5 mL bottle.

This is not really a surprise to anyone who has patients with glaucoma in his/her practice but it is nice to have some documentation published about this problem. Ophthalmologists should use this study as a reminder that we should work with our patients who are on eye drops and perhaps a refresher course on eye drop administration in the office would not be a bad idea.

Read the abstract and full-text article here (login required) in Archive of Ophthalmology.

The prospective cohort study contained 286 eyes from 286 NTG patients; 64 of the participants had SCI and 222 did not have SCI. The patients were followed for 36 months at 4 month intervals. The patients with SCI were significantly older compared to those patients who did not (72.4 versus 63.2 years, P<0.001).

The researchers found that SCI was present in 29.6% of subjects with field progression versus 15.3% of field-stable subjects (P = 0.004). A Kaplan-Meier survival analysis showed that 65.6% of SCI+ versus 45.9% of SCI– patients showed progression (P = 0.003). The SCIs were more commonly located at the basal ganglia.

These results offer food for thought as to whether preventing the silent cerebral infracts may slow or stop the visual field progression in patients with NTG. More research hopefully will clarify this issue.

Read the entire article here (login required).