Scott M. Warden

The Wnt Signaling Pathway in Familial Exudative Vitreoretinopathy and Norrie Disease

The Wnt signaling pathway is highly conserved among species and has an important role in many cell biological processes throughout the body. This signaling cascade is involved in regulating ocular growth and development, and recent findings indicate that this is particularly true in the retina. Mutations involving different aspects of the Wnt signaling pathway are being linked to several diseases of retinal development. The aim of this article is to first review the Wnt signaling pathway. We will then describe two conditions, familial exudative vitreoretinopathy (FEVR) and Norrie disease (ND), which have been shown to be caused in part by defects in the Wnt signaling cascade.

Pars plana vitrectomy in eyes treated for retinoblastoma.

Background: As conservative treatments for retinoblastoma become more prevalent, there will be a greater number of ocular complications developing in eyes that previously would have been enucleated. Pars plana vitrectomy (PPV) is needed to manage some of these complications. Methods: The authors evaluated three consecutive cases of PPV in eyes that were successfully treated for retinoblastoma from the Retina Service of the Massachusetts Eye and Ear Infirmary (MEEI) performed between 1989 and 2004. A review of the literature to date regarding PPV after treatment for retinoblastoma was also performed. Results: There was no tumor reactivation in the three cases at MEEI. Vision was maintained at light perception in one case, and there was improvement in vision from hand motions to 20/80 and 20/400 to 20/160 in two cases. Twelve of the 24 cases reviewed in the literature were found to have significant complications of recurrent tumor, need for enucleation, and/or systemic metastasis. Conclusion: PPV is associated with significant risks in eyes previously treated for retinoblastoma and should be reserved for monocular patients with no other alternative for retaining visual function. Areas that may influence outcome include different treatment modalities and length of time of documented tumor inactivity before PPV.

Inherited proliferative vitreoretinopathies of childhood.

There are a number of inherited, childhood disorders of the retinal vasculature that result in vitreoretinal proliferation. These include familial exudative vitreoretinopathy (FEVR), Norrie disease (ND), incontinentia pigmenti (IP), autosomal dominant neovascular inflammatory vitreoretinopathy (ADNI

Histology of retina overlying bacterial subretinal abscess and implications for treatment.

PURPOSE To evaluate the state of the retina overlying a subretinal abscess and its contents by histopathologic analysis and electron microscopy (EM) and to determine implications for treatment. METHODS Case report of a patient with a subretinal abscess secondary to Klebsiella pneumoniae infection who underwent pars plana vitrectomy, PPL, endolaser, retinectomy, abscess drainage, and retinal biopsy. The retinal biopsy was analyzed histologically using special stains, and EM of the abscess contents was performed. RESULTS Postoperatively, the retina remained attached, and the patient regained visual acuity of 20/60. Culture of the vitrectomy specimen yielded K. pneumoniae. Retinal biopsy revealed a partially intact inner retina with destruction of the outer retinal layers in the setting of acute inflammation. Results of gram, Grocott-Gomori methenamine-silver nitrate, and acid-fast staining of the retinal biopsy specimen were negative. EM of the abscess contents revealed cellular debris with scattered inflammatory cells but no bacteria. CONCLUSION This case demonstrates that aggressive surgical management of a subretinal abscess due to K. pneumoniae in an eye can result in useful vision. Management included retinectomy of the retina overlying the abscess that revealed photoreceptor destruction with intraretinal inflammation. Drainage of a subretinal abscess without removal of the overlying retina may limit treatment effectiveness and spare retina that is not functional.

Contact lens intraocular foreign body presenting 1 year after traumatic open globe repair.

PURPOSE To describe an intraocular contact lens presenting as a foreign body 1 year after repair of a traumatic open globe. METHOD A case report. RESULTS The patient underwent open globe repair for a scleral laceration. The patients vision returned to 20/20 and had no ocular complaints until 1 year later when he had a large floater. Examination revealed an intraocular contact lens in the anterior vitreous that was successfully removed by pars plana vitrectomy. The patients vision returned to 20/20 with resolution of his floater. CONCLUSION Ophthalmologists should be aware that a contact lens can gain access to the posterior segment in the setting of trauma. These intraocular foreign bodies can remain asymptomatic and undiagnosed for an extensive period of time until they gradually migrate into the visual axis.