Cyclodestructive Procedures in Glaucoma: A Review of Current and Emerging Options.

The first surgical modalities to reduce aqueous humor production by damaging the ciliary body date back to the early twentieth century. Until recently, however, cyclodestructive procedures (e.g., cyclocryotherapy and transscleral diode laser photocoagulation) have been reserved as last option procedures in refractory glaucoma patients with poor visual potential. Emerging technologic innovation has led to the development of promising, safer and less destructive techniques, such as micropulse diode cyclophotocoagulation, endoscopic cyclophotocoagulation and ultrasound cyclodestruction. Consequently, an emerging paradigm shift is under way with the selection of these surgical options in eyes with less severe glaucoma and good visual potential. Although existing evidence has not, as yet, adequately defined the role and value of these procedures, their emergence is a welcome expansion of available options for patients with moderate-to-severe glaucoma. This article reviews the pertinent evidence on both established and evolving cyclodestructive techniques and describes their growing role in the management of glaucoma.

Orbital cellulitis.

Orbital cellulitis (OC) is an inflammatory process that involves the tissues located posterior to the orbital septum within the bony orbit, but the term generally is used to describe infectious inflammation. It manifests with erythema and edema of the eyelids, vision loss, fever, headache, proptosis, chemosis, and diplopia. OC usually originates from sinus infection, infection of the eyelids or face, and even hematogenous spread from distant locations. OC is an uncommon condition that can affect all age groups but is more frequent in the pediatric population. Morbidity and mortality associated with the condition have declined with advances in diagnostic and therapeutic options; however, OC can still lead to serious sight- and life-threatening complications in the modern antibiotics era. Therefore, prompt diagnosis and treatment remain crucial. Antibiotic coverage, computed tomography imaging, and surgical intervention when needed have benefitted patients and changed the disease prognosis. We review the worldwide characteristics of OC, predisposing factors, current evaluation strategies, and management of the disease.

The Effect of Posture on Intraocular Pressure and Systemic Hemodynamic Parameters in Treated and Untreated Patients with Primary Open-Angle Glaucoma.

PURPOSE: To assess intraocular pressure (IOP), systolic, diastolic, and mean arterial blood pressure (SBP, DBP, MAP) changes in the sitting, supine, and 20° head-down (Trendelenburg) position in treated (tPOAG) and untreated (uPOAG) primary open-angle glaucoma patients and healthy controls. METHODS: All participants underwent IOP and systemic BP measurements in the sitting, supine, and Trendelenburg positions during office hours. IOP and BP readings in the sitting, supine, and Trendelenburg positions were analyzed. RESULTS: Twenty-one tPOAG patients, 17 uPOAG patients, and 21 controls were enrolled in the study. Compared to controls, eyes in the tPOAG and uPOAG groups had significantly larger posture-induced IOP elevation upon changing from the sitting to the supine position (P = 0.020 and P = 0.032, respectively). Compared to controls, the IOP elevation in the Trendelenburg position was statistically higher for the tPOAG (P = 0.003), but not the uPOAG group (P = 0.840). All 3 groups had a similar pattern of SBP, DBP, and MAP changes. CONCLUSIONS: Compared to controls, posture-induced IOP changes are more pronounced in treated and untreated POAG patients.

Choroidal Imaging with Swept-Source Optical Coherence Tomography in Patients with Birdshot Chorioretinopathy: Choroidal Reflectivity and Thickness.

PURPOSE: To characterize choroidal thickness and choroidal reflectivity in the eyes of patients with birdshot chorioretinopathy (BSCR). DESIGN: Cross-sectional observational study. PARTICIPANTS: Two hundred twenty BSCR patients and 59 healthy controls. METHODS: Patients with BSCR and healthy controls underwent imaging of the macula in both eyes with a swept-source optical coherence tomography device (DRI-OCT1 Atlantis; Topcon). Images were exported from the device, and analysis was performed by 2 graders in the Doheny Image Reading Center using Image J software. The choroidal thickness at the foveal center was measured. In addition, the inner and outer boundaries of the choroid and retinal pigment epithelium (RPE) as well as the inner retinal surface all were segmented to allow the brightness and reflectivity of the pixels in the choroid, RPE band, and overlying vitreous to be quantified. An adjusted or normalized choroidal reflectivity, with the RPE as the bright reference standard and the vitreous as the dark reference standard, was computed using the formula: normalized choroidal reflectivity = (choroidal reflectivity-vitreous reflectivity)/RPE reflectivity. MAIN OUTCOME MEASURES: Choroidal reflectivity and choroidal thickness. RESULTS: Three hundred eighty-six eyes in the BSCR group and 59 eyes in the control group were included in this analysis. Higher choroidal reflectivity and lower choroidal thickness were documented in inactive BSCR patients compared with active BSCR and controls (P < 0.01). Active BSCR patients showed lower choroidal thickness compared with controls (P < 0.01). There was a negative correlation between choroidal reflectivity and choroidal thickness (r = -0.793; P < 0.001). On multiple regression analysis, choroidal thickness, age, and disease duration (all P < 0.01) all were significant predictors of choroidal reflectivity. CONCLUSIONS: Choroidal reflectivity and choroidal thickness changes are evident in active and inactive BSCR patients. Novel choroidal parameters such as choroidal reflectivity may warrant further study in the setting of BSCR.

Glaucoma surgical considerations for PROSE lens use in patients with ocular surface disease.

PURPOSE: To examine challenges of Prosthetic Replacement of the Ocular Surface Ecosystem (PROSE) treatment in patients with glaucoma drainage implants (GDI) and the surgical management of patients where both GDI and PROSE treatment are indicated. METHODS: A retrospective noncomparative observational study was performed to investigate the outcomes of 7 eyes of 6 patients that required PROSE lens wear and GDI implantation. RESULTS: Group A consisted of 2 cases where PROSE lens wear was problematic due to scleral surface irregularities following GDI placement. These included changes in surface morphology caused by the elevated scleral patch graft tissue adjacent to the corneal limbus in one case and the presence of two anteriorly located shunts in the other. Group B consisted of 3 eyes where the previously placed GDI led to poor lens alignment due to the proximity of the lens edge to the scleral graft. Group C consisted of 2 cases where both patients underwent placement of the GDI in the pars plana and insertion of the drainage tube 3-3.5mm from the limbus in order to facilitate PROSE lens use. The posterior location of the tube and patch allowed for proper PROSE device alignment over the ocular surface. CONCLUSIONS: Surgical considerations and prior planning for GDI placement allows PROSE lens use for management of ocular surface disease. Pars plana tube placement with a posteriorly placed patch graft, instead of anterior chamber tube positioning with more anterior graft, enables adequate lens wear in scleral-lens-dependent patients.

Comparison of Physiologic versus Pharmacologic Mydriasis on Anterior Chamber Angle Measurements Using Spectral Domain Optical Coherence Tomography.

Purpose. To compare the effects of physiologic versus pharmacologic pupil dilation on anterior chamber angle (ACA) measurements obtained with spectral domain optical coherence tomography (SD-OCT). Methods. Forty eyes from 20 healthy, phakic individuals with open angles underwent anterior segment OCT imaging under 3 pupillary states: (1) pupil constricted under standard room lighting, (2) physiologic mydriasis in a darkened room, and (3) postpharmacologic mydriasis. Inferior angle Schwalbe's line-angle opening distance (SL-AOD) and SL-trabecular-iris-space area (SL-TISA) were computed for each eye and pupillary condition by masked, certified Reading Center graders using customized grading software. Results. SL-AOD and SL-TISA under pupillary constriction to room light were 0.87 ± 0.31 mm and 0.33 ± 0.14 mm(2), respectively; decreased to 0.75 ± 0.29 mm (P < 0.01) and 0.29 ± 0.13 mm(2) (P < 0.01), respectively, under physiologic mydriasis; and increased to 0.90 ± 0.38 mm (P < 0.01) and 0.34 ± 0.17 mm(2) (P = 0.06) under pharmacologic mydriasis compared to baseline. Conclusions. Using SD-OCT imaging, pharmacologic mydriasis yielded the widest angle opening, whereas physiologic mydriasis yielded the most angle narrowing in normal individuals with open iridocorneal angles. Accounting for the state of the pupil and standardizing the lighting condition would appear to be of importance for future studies of the angle.

Manometric measurement of the outflow facility in the living human eye and its dependence on intraocular pressure.

PURPOSE: The intraocular pressure (IOP) is determined by a dynamic equilibrium between the production and outflow of the aqueous humour. The relationship between IOP and the outflow rate through the conventional and unconventional pathway is quantified by the outflow facility coefficient (C). The purpose of this study is to employ a direct (manometric) tonographic technique and determine C as well as its inverse, resistance (R), as a function of IOP in the living human eye. METHODS: Nineteen cataract patients were enrolled in the study. An intraoperative manometric device was used to measure IOP. After cannulation of the anterior chamber, the IOP was increased by infusion of controlled amounts of saline solution. At 40 mmHg, the infusion stopped, and a pressure sensor recorded the IOP. The measured pressure-volume relationship was considered in order to convert pressure changes to corresponding ocular volume changes. An appropriate mathematical model was applied to calculate C and (its inverse), R. RESULTS: The average C was 0.0672 ± 0.0296 µl/min/mmHg at 40 mmHg and 0.2652 ± 0.1164 µl/min/mmHg at 20 mmHg. There was a strong dependence of coefficient C on IOP in all subjects (p < 0.001). The corresponding values for R were 17.9 ± 11.17 min mmHg/µl at 40 mmHg and 4.51 ± 2.69 min mmHg/µl at 20 mmHg. CONCLUSION: This study provides measurement of outflow facility and its dependence with pressure in healthy living human eyes. This relation is shown to be non-linear, using a direct manometric method.

Ocular rigidity, outflow facility, ocular pulse amplitude, and pulsatile ocular blood flow in open-angle glaucoma: a manometric study.

PURPOSE: To compare ocular rigidity (OR) and outflow facility (C) coefficients in medically treated open-angle glaucoma (OAG) patients and controls, and to investigate differences in ocular pulse amplitude (OPA) and pulsatile ocular blood flow (POBF) between the two groups. METHODS: Twenty-one OAG patients and 21 controls undergoing cataract surgery were enrolled. Patients with early or moderate primary or pseudoexfoliative OAG participated in the glaucoma group. A computer-controlled system, consisting of a pressure transducer and a microstepping device was employed intraoperatively. After cannulation of the anterior chamber, IOP was increased by infusing the eye with microvolumes of saline solution. IOP was recorded after each infusion step. At an IOP of 40 mm Hg, an IOP decay curve was recorded for 4 minutes. OR coefficients, C, OPA, and POBF were estimated from IOP and volume recordings. RESULTS: There were no differences in age or axial length in the two groups. The OR coefficient was 0.0220 ± 0.0053 µl(-1) in the OAG and 0.0222 ± 0.0039 µl(-1) in the control group (P = 0.868). C was 0.092 ± 0.082 µL/min/mm Hg in the glaucoma group compared with 0.149 ± 0.085 µL/min/mm Hg in the control group at an IOP of 35 mm Hg (P < 0.001) and 0.178 ± 0.133 µL/min/mm Hg vs. 0.292 ± 0.166 µL/min/mm Hg, respectively, at an IOP of 25 mm Hg (P < 0.001). There were no differences in OPA or POBF between the two groups in baseline and increased levels of IOP (P > 0.05). CONCLUSIONS: Manometric data reveal lower C in OAG patients and increased C with increasing IOP. There were no differences in the OR coefficient, OPA, and POBF between medically treated OAG patients and controls, failing to provide evidence of altered scleral distensibility and choroidal blood flow in OAG.

Ocular rigidity, ocular pulse amplitude, and pulsatile ocular blood flow: the effect of axial length.

PURPOSE: Previous studies have shown a negative correlation between axial length (AL) and pulsatile ocular blood flow (POBF). This relation has been questioned because of the possible confounding effect of ocular volume on ocular rigidity (OR). The purpose of this study was to investigate the relation between AL, as a surrogate parameter for ocular volume, and OR, ocular pulse amplitude (OPA), and POBF. METHODS: Eighty-eight cataract patients were enrolled in this study. A computer-controlled device comprising a microdosimetric pump and a pressure sensor was used intraoperatively. The system was connected to the anterior chamber and used to raise the intraocular pressure (IOP) from 15 to 40 mm Hg, by infusing the eye with a saline solution. After each infusion step, the IOP was continuously recorded for 2 seconds. Blood pressure and pulse rate were measured during the procedure. The OR coefficient was calculated from the pressure volume data. OPA and POBF were measured from pressure recordings. RESULTS: Median AL was 23.69 (interquartile range 3.53) mm. OR coefficient was 0.0218 (0.0053) µL(-1). A negative correlation between the OR coefficient and AL (ρ = -0.641, P < 0.001) was documented. Increasing AL was associated with decreased OPA (ρ = -0.637, P < 0.001 and ρ = -0.690, P < 0.001) and POBF (ρ = -0.207, P = 0.053 and ρ = -0.238, P = 0.028) at baseline and elevated IOP, respectively. CONCLUSIONS: Based on manometric data, increasing AL is associated with decreased OR, OPA, and POBF. These results suggest decreased pulsatility in high myopia and may have implications on ocular pulse studies and the pathophysiology of myopia.

Orbital and optic nerve complications of inflammatory bowel disease.

BACKGROUND AND AIMS: Extraintestinal manifestations of inflammatory bowel disease (IBD) can involve the orbit and the optic nerve. Although these manifestations are rare, they can be particularly serious as they can lead to permanent loss of vision. The aim of the review is to present the existing literature on IBD-related optic nerve and orbital complications. METHODS: A literature search identified the publications reporting on incidence, clinical features and management of IBD patients with optic nerve and orbital manifestations. RESULTS: Posterior scleritis and orbital inflammatory disease (orbital pseudotumor) are the most commonly encountered entities affecting the structures of the orbit. On the other hand, the optic nerve of IBD patients can be affected by conditions such as optic (demyelinating) neuritis ("retrobulbar" neuritis), or ischaemic optic neuropathy. Other neuro-ophthalmic manifestations that can be encountered in patients with IBD are related to increased intracranial pressure or toxicity secondary to anti tumour necrosis factor (anti-TNF) agents. CONCLUSIONS: IBD-related optic nerve and orbital complications are rare but potentially vision-threatening. Heightened awareness and close cooperation between gastroenterologists and ophthalmologists are warranted.

Transscleral diode laser cyclophotocoagulation for refractory glaucoma secondary to juvenile idiopathic arthritis: a short term follow-up.

To evaluate the success rates of transscleral diode cyclophotocoagulation (TD-CPC) for refractory secondary glaucoma in a paediatric patient with juvenile idiopathic arthritis. Report of a case of a 6-year-old boy suffering from severe uveitis, and secondary open angle glaucoma. The patient had undergone bilateral cataract surgery, two prior trabeculectomies in the left and one in the right eye. He was under systemic immunomodulation with methotrexate and cyclosporine. He presented with medically uncontrolled glaucoma, with an intraocular pressure (IOP) of 36 and 34 mmHg in the right and left eye, respectively, under maximal medical antiglaucoma therapy. TD-CPC was performed under general anesthesia, including a total of 20 spots in the right and 34 in the left eye (2,000 mW, 2 s/spot) applied in one session. Visual acuity remained stable in the right eye and deteriorated in the left eye from 0.1 to no light perception. Postoperative hypotony was present 1 month post op and IOP was 14 mmHg in the left and 17 mmHg in the right eye, respectively, in the 6-month follow-up with a topical beta-blocker. The anterior chamber was quiet in both eyes. TD-CPC was effective in the short term as IOP lowering therapy in a pediatric patient with refractory uveitic glaucoma.

Bimatoprost and bimatoprost/timolol fixed combination in patients with open-angle glaucoma and ocular hypertension.

PURPOSE: To investigate the intraocular pressure (IOP) lowering effect of bimatoprost (BIM) 0.03% and the potential additional effect of the BIM 0.03%/timolol 0.5% fixed combination (BTFC) in eyes with ocular hypertension, primary open-angle glaucoma, or exfoliation glaucoma. METHODS: Following an appropriate washout period that varied with previous medication, participants with ocular hypertension, primary open-angle glaucoma, or exfoliation glaucoma were treated with evening-dosed BIM for 5 weeks. They were then given evening-dosed BTFC for another 5 weeks. One randomly selected eye was evaluated. Goldmann applanation tonometry was performed by the same investigator at 8 a.m., 12 noon, 4 p.m., and 8 p.m. at baseline and at the end of each treatment period. RESULTS: Thirty-three participants completed the study. Three patients discontinued because of local adverse effects during the BIM treatment period. The mean diurnal IOP (mean ± SD) at baseline, on BIM, and on BTFC were 24.8 ± 5.4, 17.3 ± 3.5, and 14.9 ± 3.1 mmHg, respectively (repeated measures analysis of variance, P < 0.001 for all pairwise comparisons). The individual time-point IOP values showed similar significant reductions. The percentage of IOP reduction from baseline was 30.2% for BIM and 39.9% for the BTFC. The mean ± SD diurnal fluctuation at baseline was 6.8 ± 3.2 mmHg, which decreased to 4.0 ± 3.1 and 2.9 ± 1.4 mmHg on BIM and BTFC, respectively (P < 0.05 for both treatments versus baseline). CONCLUSIONS: Both BIM 0.03% and the BTFC were effective in lowering IOP in eyes with ocular hypertension and open-angle glaucoma. However, the fixed combination provided an additional statistically significant reduction in IOP compared with BIM 0.03%.

Ocular rigidity, ocular pulse amplitude, and pulsatile ocular blood flow: the effect of intraocular pressure.

PURPOSE: The purpose of this study was to characterize the pressure-volume relation in the living human eye, measure the ocular pulse amplitude (OPA), and calculate the corresponding pulsatile ocular blood flow (POBF) in a range of clinically relevant IOP levels. METHODS: Fifty patients with cataract (50 eyes) were enrolled in the study. After cannulation of the anterior chamber, a computer-controlled device for the intraoperative measurement and control of IOP was used to artificially increase the IOP in a stepping procedure from 15 to 40 mm Hg. The IOP was continuously recorded for 2 seconds after each infusion step. The pressure-volume relation was approximated with an exponential fit, and the ocular rigidity coefficient was computed. OPA, pulse volume (PV), and POBF were measured from the continuous IOP recordings. RESULTS: The average rigidity coefficient was 0.0224 microL(-1) (SD 0.0049). OPA increased by 91% and PV and POBF decreased by 29% and 30%, respectively, when increasing the IOP from 15 to 40 mm Hg. The OPA is positively correlated with the coefficient of ocular rigidity (r = 0.65, P < 0.01). CONCLUSIONS: The present results suggest a nonlinear pressure-volume relation in the living human eye characterized by an increase in rigidity at higher IOP levels. The increased OPA and decreased pulse volume relate to the decreased POBF and the increased mechanical resistance of the ocular wall at high IOP levels.