Pharmacotherapy for diabetic retinopathy

BACKGROUND

Diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR) continue to cause significant visual loss among patients with diabetes mellitus. In some patients unresponsive to standard laser techniques, as well as improved control of blood pressure and blood sugar, pharmacologic treatment may be beneficial. Although no agent is now approved by the FDA for this purpose, many agents are now being studied in randomized clinical trials (RCTs).

OBJECTIVE

To review concisely the chief pharmacotherapies for diabetic retinopathy available at present.

METHODS

Literature review and synopsis.

RESULTS

Used alone, intravitreal triamcinolone acetonide (IVTA) seems to have some short-term efficacy against DME, but longer-term outcomes (< or = 3 years) using IVTA monotherapy showed a lesser benefit than focal/grid laser treatment in a prospective RCT done by the Diabetic Retinopathy Clinical Research Network. Intravitreal anti-VEGF agents have demonstrated some short-term efficacy against DME, and continuing RCTs will evaluate combination therapies (anti-VEGF and laser) for both DME and PDR. Other agents are being evaluated in pilot studies and Phase II RCTs.

CONCLUSION

Pharmacotherapies for DME and PDR have potential for vision stabilization or improvement. Continuing RCTs will provide evidence-based data on their role in clinical practice. A potential role for pharmacotherapy in the prevention of DME and PDR is also emerging.

Treatment of cystoid macular edema with the new-generation NSAID nepafenac 0.1%

Purpose:

To describe the use of nepafenac 0.1% for cystoid macular edema (CME).

Methods:

This was a multicenter retrospective review of 22 CME cases (20 patients) treated with nepafenac 0.1% (six with concomitant prednisolone acetate 1%) from December 2005 to April 2008: three acute pseudophakic CME cases, 13 chronic/recalcitrant pseudophakic CME cases, and six cases of uveitic CME. Pre- and post-treatment retinal thickness and visual acuity were reported.

Results:

Following treatment for six weeks to six months, six eyes with uveitic CME showed a mean retinal thickness improvement of 227 ± 168.1 μm; mean best-corrected visual acuity (BCVA) improvement was 0.36 ± 0.20 logMAR. All three cases of acute pseudophakic CME improved after four to 10 weeks of nepafenac, with a mean improvement in retinal thickness of 134 ± 111.0 μm. BCVA improved in two patients (0.16 and 0.22 logMAR) but not in the third due to underlying retinal pigment epithelium changes. Thirteen eyes with chronic/recalcitrant pseudophakic CME demonstrated a mean improvement in retinal thickness of 178 ± 128.7 μm after nepafenac and mean BCVA improvement of 0.33 ± 0.19 logMAR.

Conclusion:

The positive outcomes of these 22 eyes strongly suggest that nepafenac 0.1% is a promising drug for the treatment of CME. Additional study under randomized controlled conditions is warranted.

Charles Bonnet syndrome: a review

PURPOSE OF REVIEW

The aging of the population and the resultant increase in the number of patients with low vision due to age-related macular degeneration and other ocular diseases necessitate an increase in awareness of the Charles Bonnet syndrome among ophthalmic care providers.

RECENT FINDINGS

The clinical features of Charles Bonnet syndrome have been described by several different authors as formed visual hallucinations due to disturbances of the visual system in patients who are otherwise mentally normal. Theories regarding the causes underlying the Charles Bonnet syndrome are multifaceted and offer insight into the function of the visual system. The incidence of the Charles Bonnet syndrome varies among different population groups, but is underdiagnosed in most settings. Recent case reports of treatment options involve varied pharmacologic interventions, but visual improvement and patient reassurance remain the mainstays of treatment.

SUMMARY

As Charles Bonnet syndrome becomes more prevalent as the population ages, all physicians who care for low vision or elderly patients should be aware of its clinical characteristics and treatment options. Understanding of this syndrome by caregivers will lead to decreased anxiety among the patients who experience it. Further exploration of treatment options will be necessary in the future.

Dyskeratosis congenita

Dyskeratosis congenita (DC) is an inherited bone marrow failure syndrome characterized clinically by the triad of abnormal nails, reticular skin pigmentation, and oral leukoplakia, and is associated with high risk of developing aplastic anemia, myelodysplastic syndrome, leukemia, and solid tumors. Patients have very short germline telomeres, and approximately half have mutations in one of six genes encoding proteins that maintain telomere function. Accurate diagnosis of DC is critical to ensure proper clinical management, because patients who have DC and bone marrow failure do not respond to immunosuppressive therapy and may have increased morbidity and mortality associated with hematopoietic stem cell transplantation.

Acute syphilitic posterior placoid chorioretinitis in late latent syphilis

Summary

Diverse manifestations of ocular syphilis may involve any structure in the eye, at any stage of the disease. Posterior uveitis in the form of posterior placoid chorioretinitis has been described in secondary- and tertiary-acquired syphilis. In this case report, we present a 47-year-old man with late latent syphilitic infection and fundoscopic, as well as angiographic findings consistent with acute syphilitic posterior placoid chorioretinitis. To our knowledge this form of patchy multifocal choroiditis has never been described in the latent stage of the disease.

[Intravitreous injection: retrospective study on 2028 injections and their side effects]

OBJECTIVE

To observe the tolerance of repeated intravitreous injections over the short and long term and to analyze their complications.

PATIENTS AND METHODS

The clinical records of consecutive patients having one or several intravitreous injections between 2002 and 2007 were evaluated, for all indications except the treatment of endophthalmitis.

RESULTS

2028 intravitreous injections were performed, mainly for age-related macular degeneration (n=1 192) or macular edema secondary to diabetes mellitus or retinal vein occlusion (n=41). The injected drug was triamcinolone acetonide 4 mg (339 injections), pegaptanib sodium 0.3 mg (1179 injections), and ranibizumab 0.3 (497 injections). The patients received 1-27 intravitreous injections per eye. The main complications were endophthalmitis (two after triamcinolone, 0.1% of the total group), pseudoendophthalmitis (two after triamcinolone, 0.1% of the total group), hypertony (7.69% of the total group, 13.78% after triamcinolone, 3.56% after pegaptanib, 1.21% after ranibizumab), including five cases of acute hypertony with transient light perception loss after ranibizumab, cataract (0.44% of total group), and macular hole (one patient after triamcinolone). No case of retinal detachment nor systemic complication was observed.

DISCUSSION

Most of the complications were observed with the use of nonfiltered triamcinolone. The incidence of endophtalmitis was considerably lower with increased experience and the use of a dedicated room for the injections. Repeated injections were locally well tolerated.

CONCLUSION

With the strict respect of asepsis rules, intravitreous injection seems well tolerated over the short and long term.

The competency of pars plana vitrectomy incisions: a comparative histologic and spectrophotometric analysis

PURPOSE

To compare the relative competency of pars plana vitrectomy (PPV) sclerotomies.

DESIGN

Laboratory investigation.

METHODS

PPV was performed in human cadaveric eyes using 20-gauge (20 G), 23-gauge (23 G), and 25-gauge (25 G) instrumentation. India ink was applied over a sclerotomy site while the intraocular pressure was varied. The presence of India ink particles (IIPs) along incisions was evaluated by histologic analysis. Spectrophotometric absorbance levels of vitreous aspirates were measured.

RESULTS

PPV was performed in a control eye and two eyes, each using standard 20 G, standard 23 G, perpendicular 25 G, and beveled 25 G instrumentation incisions. IIPs were not detected in the 20 G incisions either on histology or by spectrophotometry. IIPs were detected along the entire incision length in one of two eyes with 23 G sclerotomies and confirmed by spectrophotometry. IIPs were detected along the entire incision length in one of two eyes with 25 G perpendicular sclerotomies and confirmed by spectrophotometry in both eyes. IIPs were noted partially along the length in one of the two beveled 25 G eyes, but not detected in either eye by spectrophotometry.

CONCLUSIONS

During the early postoperative period, sutureless vitrectomy incisions may allow entry of ocular surface fluid. These findings may provide a pathophysiologic mechanism for the reported increased risk of endophthalmitis in small-gauge vitrectomy surgery.

A pilot study of intravitreal bevacizumab for the treatment of central serous chorioretinopathy (case reports)

BACKGROUND

We report the use of intravitreal bevacizumab as a new option in the treatment of central serous chorioretinopathy (CSC).

METHODS

Five eyes with retinal pigment epithelium (RPE) leaks secondary to CSC received intravitreal bevacizumab (2.5 mg/0.1 cc), and underwent best corrected visual acuity, fluorescein angiography and optical coherent tomography before, 1, 3 and 6 months after treatment.

RESULTS

All patients showed improvement in visual acuity, fluorescein angiographic leakage, and reduced or resolved neurosensory detachment following treatment.

CONCLUSIONS

Intravitreal injection of bevacizumab was associated with visual improvement and reduced neurosensory detachment without adverse events in patients with CSC. Although these results are promising, further investigations would be helpful to understand this therapy for patients with CSC.

Cancer risk assessment and the genetic counseling process: using hereditary breast and ovarian cancer as an example

While only a small proportion of cancers can be attributed to a hereditary susceptibility, identifying high-risk individuals plays an essential role in medical management and has a significant impact on the patient as well as their immediate and extended family members. This paper aims at increasing the medical professionals' knowledge of the components of a genetic counseling session, with particular attention toward identifying at-risk individuals and understanding the complexities of the testing process. In addition, tools are provided to assist in identifying these individuals in clinical practice and streamlining the referral process to a cancer genetics center.