Aqueous misdirection syndrome post silicone oil removal in a vitrectomized eye - a case report.

PUROPSE: Aqueous misdirection syndrome (AMS) is an aggressive post-operative glaucoma unresponsive to conventional measures with grave outcomes. In this report, we describe a rare case of AMS following silicon oil removal in a vitrectomized eye. METHODS: A diabetic patient with tractional retinal detachment underwent pars plana vitrectomy with silicon oil injection. Following retinal reattachment, silicon oil removal was performed at three months. Post oil removal she developed increased intraocular pressure with shallowing of both the peripheral and central anterior chamber suggestive of AMS. RESULTS: Initial medical management with anti-glaucoma medications and cycloplegics was not beneficial. A pars plana lensectomy with complete anterior hyaloidectomy along with a surgical peripheral iridectomy helped relieve the aqueous misdirection. CONCLUSION: AMS can rarely occur following vitrectomy and is likely secondary to intact anterior hyaloid. Lensectomy along with zonulo-hyaloido-iridectomy is essential. This report highlights the occurrence of this rare complication and its effective management.

Outcomes and Reasons for Late Presentation of Lens Induced Glaucoma: A Prospective Study.

PURPOSE: To determine the clinical outcomes and causes of late presentation in lens induced glaucoma (LIG). DESIGN: Prospective observational study. PARTICIPANTS: One hundred sixty-five patients with LIG who underwent cataract surgery. METHODS: Preoperative data collection included a questionnaire about reasons for late presentation, socioeconomic status, visual acuity, intraocular pressure (IOP), and the lens and angle status of the fellow eye. All patients underwent manual small-incision cataract surgery. Postoperative vision, IOP, the anterior segment, and the fundus were evaluated at days 1, 15, and 30. MAIN OUTCOME MEASURES: Reasons for late presentation, status of the fellow eyes, and surgical outcomes, including visual acuity and IOP at the 1-month postoperative visit. RESULTS: Mean age at presentation was 63.8 years, and the female-to-male ratio was 1.4:1. Of the entire cohort, 70.3% were phacolytic and 29.7% had phacomorphic glaucoma. The main causes for late presentation was nonfinancial (81.2%); of these, good vision in fellow eye and lack of escort to the hospital were the major reasons. Most fellow eyes were pseudophakic (72.1%). After surgery, 75.6% gained best-corrected visual acuity of 6/18 or more. Six percent experienced poor visual recovery (≤6/60) with optic atrophy as the major cause. Only 7.9% required further glaucoma management in the form of topical medications. Delayed presentation (>15 days) was associated with poor visual outcome. CONCLUSIONS: Nonfinancial causes, including good vision in the fellow eye and lack of escort, were the major determinants of late presentation. Most patients were pseudophakic in the fellow eye. After cataract extraction, only a few LIG patients required further glaucoma management.

Radiation-induced neovascular glaucoma: A devastating disease.

Neovascular glaucoma (NVG) is a potentially blinding form of secondary glaucoma, with radiation being one of the rare causes. This report is aimed to discuss a case of NVG caused secondary to radiotherapy (RT) given for a nasal malignancy. A 50-year-old male presented with enophthalmos, dry eye, and NVG 3 years after receiving RT for chondrosarcoma of nasal and paranasal cavities. He was given topical antiglaucoma medications, retinal laser, and intravitreal bevacizumab injection and thus prevented the eye from becoming a painful blind eye. The radiation oncologist and ear, nose, and throat specialists have to liaise closely with ophthalmologist when patients receive radiation involving the eye in the treatment field to prevent, diagnose, and treat this devastating condition.

Safety and Efficacy of 0.1% Nepafenac versus 1% Prednisolone Acetate Eye Drops after Laser Peripheral Iridotomy: A Prospective, Randomized Trial.

PURPOSE: To compare 0.1% nepafenac, a topical nonsteroidal anti-inflammatory drop, with 1% prednisolone acetate in controlling inflammation after neodymium:yttrium-aluminum-garnet laser peripheral iridotomy (LPI) in primary angle-closure suspects (PACS). DESIGN: Randomized controlled trial. PARTICIPANTS: One hundred fifty-two PACS undergoing bilateral LPI. METHODS: Patients were randomized to 0.1% nepafenac or 1% prednisolone acetate eye drops in both eyes. Medications were given 4 times daily for 7 days, then twice daily for additional 7 days. Investigators were masked to the type of medication. Right eyes in patients with bilateral PACS and the PACS eye in asymmetrical disease (primary angle closure in fellow eye) were analyzed. MAIN OUTCOME MEASURES: Noninferior control of inflammation, defined as absence of cell in the anterior chamber at 2 weeks and absence of rebound iritis with medication discontinuation, was the primary outcome, whereas difference in the rise in intraocular pressure (IOP) was a secondary outcome. RESULTS: Both groups were comparable in baseline characteristics, including IOP and total laser energy. Nepafenac was noninferior to prednisolone with regard to inflammation control, with 1 nepafenac-treated eye (1.3%) not meeting the primary end point because of 1+ anterior chamber cell at 2 weeks and 4 prednisolone-treated eyes (5.4%) failing to meet the primary end point because of rebound iritis (P < 0.001). A greater increase in IOP from baseline to 2 weeks was observed in the prednisolone group compared with the nepafenac group (+2.6 mmHg vs. +0.6 mmHg; P = 0.004), although at 4 weeks, IOP was not significantly different than baseline in either group (P > 0.05 for both). Two weeks after LPI, 3 nepafenac-treated eyes and 10 prednisolone-treated eyes demonstrated a 6- to 15-mmHg IOP elevation from baseline (P = 0.10), whereas 2 prednisolone-treated eyes and no nepafenac-treated eyes showed IOP elevation of more than 15 mmHg (P = 0.20). Four weeks after LPI, more prednisolone-treated eyes showed IOP elevation of 6 to 15 mmHg as compared with nepafenac-treated eyes (6 eyes vs. 1 eye; P = 0.04); no eyes showed IOP elevation of more than 15 mmHg. CONCLUSIONS: Nepafenac was noninferior to prednisolone in controlling inflammation after LPI in PACS.

Comparison of New Visual Disturbances after Superior versus Nasal/Temporal Laser Peripheral Iridotomy: A Prospective Randomized Trial.

PURPOSE: To determine whether laser peripheral iridotomy (LPI) location affects postoperative dysphotopsia symptoms. DESIGN: Multicenter, randomized, prospective, single-masked trial. PARTICIPANTS: Five hundred fifty-nine South Indian patients 30 years of age or older diagnosed as primary angle-closure suspects (PACSs) or with primary angle closure (PAC) or primary angle-closure glaucoma (PACG) in both eyes. METHODS: Patients were randomized to either bilateral superior or bilateral nasal/temporal LPI. Occurrence of new visual disturbances was evaluated before and 2 weeks after LPI using a questionnaire based on the 7-item dysphotopsia symptoms described by Spaeth et al. MAIN OUTCOME MEASURES: New-onset dysphotopsia symptoms. RESULTS: Superior LPI (n = 285) and nasal/temporal LPI (n = 274) patients were matched for age (P = 0.6), gender (P = 0.7), and distribution of PACS versus PAC or PACG (P = 0.7). Similar initial laser energy settings were used in both groups (P = 0.3), although superior LPIs required more shots (P = 0.006) and greater total energy (P < 0.001) than nasal/temporal LPIs. No significant differences in postoperative anterior chamber reaction (P = 0.7) or LPI area (P = 0.9) were noted between the 2 groups. No group differences were noted regarding the proportion of patients demonstrating 1 or more dysphotopsia symptoms before LPI (15.8% for superior vs. 13.9% for nasal/temporal; P = 0.1) or any individual dysphotopsia symptom (P > 0.2 for all). After LPI, 8.9% of all patients reported 1 or more new symptoms, the most common consisting of linear dysphotopsias, glare, and blurring in 2.7%, 4.3%, and 4.3% of patients, respectively. Patients undergoing superior LPI were not more likely to describe the new onset of 1 or more dysphotopsia symptoms as compared with patients undergoing nasal/temporal LPI (8.4% vs. 9.5%; P = 0.7), nor did the frequency of any new individual symptoms differ by group (P ≥ 0.3 for all). In multivariate logistic regression analysis, neither LPI location nor LPI area nor total laser energy predicted higher odds of new postoperative dysphotopsias (P > 0.1 for all). CONCLUSIONS: Laser peripheral iridotomy likely is safe with respect to visual dysphotopsias regardless of location, LPI size, and amount of laser energy used.

Multiplex Cytokine Analysis of Aqueous Humor from the Patients with Chronic Primary Angle Closure Glaucoma.

PURPOSE: To compare the levels of cytokines and growth factor in aqueous humor of the patients with chronic primary angle closure glaucoma (PACG) and cataract. METHODS: Aqueous humor samples were collected from 19 chronic PACG patients and compared with 14 nonglaucomatous controls presenting for cataract surgery. The levels of 27 cytokines and growth factors were measured in the aqueous samples using multiplex bead immunoassay and compared across groups. RESULTS: Significantly higher levels of interleukin (IL)-8 (p < 0.001), eotaxin (p < 0.001), interferon gamma-induced protein (IP)-10 (p < 0.001) and macrophage inflammatory protein-1-beta (MIP-1ß; p < 0.001) were observed in aqueous of chronic PACG patients compared to controls. In comparison to controls, significantly lower levels of IL-9 (p = 0.001), IL-17 (p < 0.001), tumor necrosis factor-alpha (TNF-α; p < 0.001), granulocyte-macrophage colony-stimulating factor (GM-CSF; p < 0.001), and IL-5 (p = 0.001) were observed in chronic PACG eyes. All other assayed cytokines-IL-1ß, interleukin-1 receptor antagonist (IL-1rα), IL-6, IL-7, IL-10, IL-12, IL-13, IL-15, fibroblast growth factor-basic (FGF-basic), granulocyte colony-stimulating factor (G-CSF), monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-1-alpha (MIP-1α), and vascular endothelial growth factor (VEGF) -showed no significant difference between the groups. CONCLUSIONS: These results suggest that the aqueous cytokine levels of chronic PACG eyes differ significantly from nonglaucomatous eyes. This is the first study reporting significantly increased levels of eotaxin, MIP-1ß, and IP-10 and lower levels of TNF-α, IL-5, IL-9, IL-17, and GM-CSF in chronic PACG patients, suggesting a plausible role of these inflammatory cytokines in its pathogenesis.

E-cigarettes: How "safe" are they?

Without tobacco, tar, ash, or carbon monoxide, e-cigarettes are marketed as "healthier" alternatives to cigarettes. But they are not without risk.

Investigation of effect of reconstruction filters on cone-beam computed tomography image quality.

Cone-beam CT (CBCT) using kV imagers integrated with linear accelerators is now widely used in verifying patient position during radiation therapy. Current CBCT acquisition protocols have lowered tube current to keep the imaging dose to a minimum. This affects the usability of CBCT data sets in treatment planning by reducing the soft tissue contrast and accuracy of CT numbers (Hounsfield values). The purpose of this study is to investigate the effect of reconstruction filters on full-fan and half-fan acquisition modes of CBCT and assess the image quality parameters of contrast- to -noise ratio, spatial resolution, pixel stability and uniformity. The results of this study show the relation between the noise and resolution of a CBCT image by using different reconstruction filters and provide possible estimations of the impact of filters on image quality and subsequent optimization for image-guided radiotherapy purposes.

Applications of linac-mounted kilovoltage Cone-beam Computed Tomography in modern radiation therapy: A review.

The use of Cone-beam Computed Tomography (CBCT) in radiotherapy is increasing due to the widespread implementation of kilovoltage systems on the currently available linear accelerators. Cone beam CT acts as an effective Image-Guided Radiotherapy (IGRT) tool for the verification of patient position. It also opens up the possibility of real-time re-optimization of treatment plans for Adaptive Radiotherapy (ART). This paper reviews the most prominent applications of CBCT (linac-mounted) in radiation therapy, focusing on CBCT-based planning and dose calculation studies. This is followed by a concise review of the main issues associated with CBCT, such as imaging artifacts, dose and image quality. It explores how medical physicists and oncologists can best apply CBCT for therapeutic applications.