The CYP1B1 gene encodes a cytochrome p450 monooxygenase enzyme, and over 150 variants have been associated with a spectrum of eye diseases, including primary congenital glaucoma, anterior segment dysgenesis, juvenile open-angle glaucoma, and primary open-angle glaucoma. Clinical genetics has yielded insights into the functions of the various CYP1B1 gene domains; however, animal studies are required to investigate the molecular role of CYP1B1 in the eye. While both zebrafish and mice express CYP1B1 in the developing eye, embryonic studies have shown disparate species-specific functions. In zebrafish, CYP1B1 regulates ocular fissure closure such that overexpression causes a remarkable phenotype consisting of the absence of the posterior eye wall. Adult CYP1B1 null zebrafish lack an ocular phenotype but show mild craniofacial abnormalities. In contrast, CYP1B1^−/− mice display post-natal mild to severe trabecular meshwork degeneration due to increased oxidative stress damage. Interestingly, the retinal ganglion cells in CYP1B1 null mice may be more susceptible to damage secondary to increased intraocular pressure. Future studies, including detailed genotype–phenotype information and animal work elucidating the regulation, substrates, and downstream effects of CYP1B1, will yield important insights for developing molecularly targeted therapies that will aim to prevent vision loss in CYP1B1-related eye diseases.

Purpose of Review: The purpose of this article is to present a critical appraisal of current therapeutic and surgical strategies for patients with nystagmus and associated oscillopsia. Different forms of nystagmus and associated oscillopsia as well as evidence supporting successful use of prism and surgical treatment of these patients are considered. Recent Findings: Low power yoked prisms are effective and under-utilized in the treatment of infantile nystagmus syndrome (INS). Surgical treatments for INS and acquired nystagmus are still being refined and studied, with future clinical trials required for additional assessment of the efficacy of various surgical treatments for acquired nystagmus and oscillopsia. Summary: Nystagmus is an involuntary, uncontrolled rhythmic movement of the eyes initiated by slow drift of the eyes and can have many diverse underlying etiologies. Nystagmus can reduce visual acuity as result of decreased centering of images on the fovea, the cone-rich center of the retina responsible for maximum visual sharpness and color vision. Steady foveal fixation is required for high-resolution tasks like reading or facial recognition. Acquired nystagmus also often causes the uncomfortable symptom of oscillopsia or shaking of the visual environment. Accurate diagnosis requires a comprehensive examination often including neurological evaluation. Important clinical considerations in the evaluation of these patients includes age of onset, direction of nystagmus, presence of abnormal head posture (AHP) or possible underlying systemic or neurological conditions. Treatment of nystagmus focuses on shifting the null point, the specific direction of gaze where nystagmus is minimized, to improve visual function in primary position and reduce AHP and bothersome oscillopsia. Prism therapy, including the use of yoked prisms, can shift the null point towards primary gaze and in doing so can also reduce abnormal head posture. Surgical management, including the Anderson-Kestenbaum procedure and extraocular muscle recession techniques, may be considered when conservative treatment is insufficient. However, further clinical research is needed to better evaluate surgical treatment outcomes, especially for patients with acquired nystagmus.

Objective: Assess visual acuity (VA) and strabismus changes in children after Baerveldt 350 (BV350) device placement. Methods and Analysis: Retrospective cohort study of children (6-month follow-up. Ocular diagnoses, surgical details, and preoperative and final follow-up exam findings were collected. In bilateral cases, first eye implanted was included in analysis. Results: Ninety-seven patients underwent BV350 surgery with median age of 6.7 (interquartile (IQR) 3.1, 11.2) years and with a median of 4.2 (IQR 1.8, 6.8) years of follow-up. Most common glaucomas were secondary to non-acquired ocular anomaly (n = 31) or primary congenital glaucoma (n = 21). There was no difference in preoperative and final VA (p = 0.6583). Twenty-seven (28%) and twenty-five (26%) patients were orthophoric preoperatively and at final follow-up, respectively. Orthophoria at final follow-up was associated with preoperative (odds ratio (OR)1.8 [1.2, 2.9]) and final VA (OR1.5 [1.1, 2.3]). At final follow-up, 13 patients (13%) and 19 patients (20%) showed worsened or improved horizontal deviation (>10 prism diopter (PD) change), respectively. No patients reported postoperative diplopia. Only four patients, all with esotropia, underwent subsequent strabismus surgery. Conclusions: Children who underwent BV350 placement did not have significant change in VA, and a high percentage of patients had strabismus prior to (72%) and following (74%) glaucoma surgery. Orthophoria was associated with better VA. The majority of patients did not show worsening of strabismus postoperatively, and none reported diplopia.