All Publications

  • Modeling absolute zone size in retinopathy of prematurity in relation to axial length. Scientific reports Wang, S. K., Korot, E., Zaidi, M., Ji, M. H., Al-Moujahed, A., Callaway, N. F., Kumm, J., Moshfeghi, D. M. 2022; 12 (1): 4717


    Treatment outcomes in retinopathy of prematurity (ROP) are closely correlated with the location (i.e. zone) of disease, with more posterior zones having poorer outcomes. The most posterior zone, Zone I, is defined as a circle centered on the optic nerve with radius twice the distance from nerve to fovea, or subtending an angle of 30 degrees. Because the eye enlarges and undergoes refractive changes during the period of ROP screening, the absolute area of Zone I according to these definitions may likewise change. It is possible that these differences may confound accurate assessment of risk in patients with ROP. In this study, we estimated the area of Zone I in relation to different ocular parameters to determine how variability in the size and refractive power of the eye may affect zoning. Using Gaussian optics, a model was constructed to calculate the absolute area of Zone I as a function of corneal power, anterior chamber depth, lens power, lens thickness, and axial length (AL), with Zone I defined as a circle with radius set by a 30-degree visual angle. Our model predicted Zone I area to be most sensitive to changes in AL; for example, an increase of AL from 14.20 to 16.58mm at postmenstrual age 32weeks was calculated to expand the area of Zone I by up to 72%. These findings motivate several hypotheses which upon future testing may help optimize treatment decisions for ROP.

    View details for DOI 10.1038/s41598-022-08680-5

    View details for PubMedID 35304549

  • Telemedicine screening for syphilitic chorioretinitis in the SUNDROP cohort. Eye (London, England) Zaidi, M. H., Rosenblatt, T. R., Al-Moujahed, A., Vail, D., Callaway, N. F., Nguyen, Q. D., Moshfeghi, D. M. 2022

    View details for DOI 10.1038/s41433-022-01967-x

    View details for PubMedID 35217825

  • Ocular Gene Therapy: A Literature Review with Special Focus on Immune and Inflammatory Responses. Clinical ophthalmology (Auckland, N.Z.) Ghoraba, H. H., Akhavanrezayat, A., Karaca, I., Yavari, N., Lajevardi, S., Hwang, J., Regenold, J., Matsumiya, W., Pham, B., Zaidi, M., Mobasserian, A., DongChau, A. T., Or, C., Yasar, C., Mishra, K., Do, D., Nguyen, Q. D. 2022; 16: 1753-1771


    Gene therapy has emerged as a research topic of choice in recent years. The eye in particular is one of few organs of the body for which gene therapy has received Food and Drug Administration approval, and it remains a field of great interest for gene therapy development. However, its associated immune and inflammatory reactions may render the treatment ineffective or harmful, which are of particular concern for the eyes due to their susceptibility to inflammation. The severity of immune and inflammatory reactions depends on the choice of vector and its route of administration. Furthermore, most preclinical and clinical studies have shown that the dose of vectors is correlated with the degree of humoral response and ocular inflammation. The route of administration directly impacts the degree of immune and inflammatory reaction. Subretinal delivery produces a weaker humoral response than the intravitreal route. However, some studies have demonstrated that the subretinal delivery induces a stronger inflammatory reaction. On the other hand, several instances of vision loss due to severe late onset intraocular inflammation were reported in a clinical trial involving intravitreal delivery of viral vectors. When compared with the intravitreal route, suprachoroidal gene delivery has been shown to produce weaker humoral response. However, unlike the subretinal space, the suprachoroidal space is not known to have immune privilege status. Inflammatory reactions following ocular gene therapy are typically mild and most clinical and preclinical studies have shown that they can be controlled with topical, local or systemic steroids. However, severe inflammatory responses may occur and require aggressive management to avoid permanent vision loss. Further investigations are required to elucidate and expand our knowledge of inflammatory reactions, and their optimal management, following ocular gene therapy.

    View details for DOI 10.2147/OPTH.S364200

    View details for PubMedID 35685379

  • Unilateral acute anterior uveitis with macular edema following the use of sildenafil citrate in a patient with HLA-B27 positivity. American journal of ophthalmology case reports Regenold, J., Ghoraba, H., Akhavanrezayat, A., Matsumiya, W., Mobasserian, A., Karaca, I., Zaidi, M., Pham, B., Nguyen, Q. D. 2021; 24: 101228


    Purpose: To present a case of acute anterior uveitis with macular edema associated with sildenafil citrate use in an HLA-B27 positive patient.Observations: A 54-year-old Caucasian male presented at an ophthalmology tertiary center with complaint of pinkish discoloration, irritation, and photophobia in the left eye (OS). He noted that these symptoms appeared one day after using sildenafil for the first time to treat his erectile dysfunction. The patient had no significant ocular history besides refractive surgery in both eyes (OU) and his medical history was insignificant. Best-corrected visual acuity (BCVA) was 20/20 in the right eye (OD) and 20/25 in OS. Slit-lamp-examination (SLE) demonstrated trace cells and 1+ flare in the anterior chamber (AC) in OS and was nonrevealing in AC in OD. Spectral domain optical coherence tomography (SD-OCT) showed parafoveal subretinal hyperreflective deposits in OU. The patient was diagnosed with acute anterior uveitis (AAU) in the left eye and was placed on topical prednisolone acetate.At 2-week follow-up, the patient reported that his eye symptoms had improved since starting topical steroids but worsened again two days after he had used sildenafil for a second time. In OS, best-corrected visual acuity (BCVA) worsened to 20/40, and SLE revealed 1+ cells and 1+ flare in AC. SD-OCT revealed cystoid macular edema only in OS. Fluorescein angiography showed mild staining around the optic disc and significant macular leakage in OS and minimal macular leakage in OD. Uveitis evaluations revealed that the patient was human leukocyte antigen-27 (HLA-B27) positive. The patient was asked to remain off sildenafil and continue topical prednisolone acetate. At 3-month follow-up, BCVA improved to 20/20 in OS with no evidence of active inflammation.Conclusions and importance: Sildenafil citrate use might be associated with new onset of intraocular inflammation in predisposed patients. Further studies are necessary to establish this relationship.

    View details for DOI 10.1016/j.ajoc.2021.101228

    View details for PubMedID 34761138

  • Inferring retinal ganglion cell light response properties from intrinsic electrical feature Zaidi, M., Aggarwal, G., Shah, N. P., Karniol-Tambour, O., Goetz, G., Madugula, S., Gogliettino, A. R., Wu, E. G., Kling, A., Brackbill, N., Sher, A., Litke, A. M., Chichilnisky, E. J. ASSOC RESEARCH VISION OPHTHALMOLOGY INC. 2021