Davin Johnson

Rate of serious adverse effects in a series of bevacizumab and ranibizumab injections

OBJECTIVE To compare the rate of serious ocular and systemic adverse effects of intravitreal bevacizumab and ranibizumab in the treatment of a variety of eye diseases. DESIGN Retrospective chart review. PARTICIPANTS Consecutive series of intravitreal injections of bevacizumab (n = 693) and ranibizumab (n = 891). METHODS Medical records of all patients receiving injections in the series were retrieved. We considered the rate of both serious ocular adverse effects (e.g., acute intraocular inflammation, infectious endophthalmitis, retinal detachment, vitreous hemorrhage) and of arterial thromboembolic events that occurred within 1 month of injection. RESULTS Subjects who received bevacizumab were 12 times more likely to develop severe intraocular inflammation following each injection than were those who received ranibizumab (OR = 11.71; 95% CI 1.5-93). The 1 case of acute intraocular inflammation following ranibizumab injection was mild and not associated with vision loss. No other serious ocular complications were noted. A trend was also noted toward an increased risk for arterial thromboembolic events in patients receiving bevacizumab, although the confidence interval was wide (OR = 4.26; 95% CI 0.44-41). CONCLUSIONS Significant concern still exists regarding the safety of off-label use of intravitreal bevacizumab. Patients receiving bevacizumab should be counselled regarding a possible increased risk for serious adverse events.

Do Findings on Routine Examination Identify Patients at Risk for Primary Open-Angle Glaucoma?: The Rational Clinical Examination Systematic Review

IMPORTANCE Glaucoma is the second leading cause of blindness worldwide, and its insidious onset is often associated with diagnostic delay. Since glaucoma progression can often be effectively diminished when treated, identifying individuals at risk for glaucoma could potentially lead to earlier detection and prevent associated vision loss. OBJECTIVE To quantify the diagnostic accuracy of examination findings and relevant risk factors in identifying individuals with primary open-angle glaucoma (POAG), the most common form of glaucoma in North America. DATA SOURCES Structured Medline (January 1950-January 2013) search and a hand search of references and citations of retrieved articles yielding 57 articles from 41 studies. STUDY SELECTION Population-based studies of high-level methods relating relevant examination findings of cup-to-disc ratio (CDR), CDR asymmetry, intraocular pressure (IOP), and demographic risk factors to the presence of POAG. RESULTS The summary prevalence of glaucoma in the highest-quality studies was 2.6% (95% CI, 2.1%-3.1%). Among risk factors evaluated, high myopia (≥6 diopters; odds ratio [OR], 5.7; 95% CI, 3.1-11) and family history (OR, 3.3; 95% CI, 2.0-5.6) had the strongest association with glaucoma. Black race (OR, 2.9; 95% CI, 1.4-5.9) and increasing age (especially age >80 years; OR, 2.9; 95% CI, 1.9-4.3) were also associated with an increased risk. As CDR increased, the likelihood for POAG increased with a likelihood ratio (LR) of 14 (95% CI, 5.3-39) for CDR of 0.7 or greater. Increasing CDR asymmetry was also associated with an increased likelihood for POAG (CDR asymmetry ≥0.3; LR, 7.3; 95% CI, 3.3-16). No single threshold for CDR or asymmetry ruled out glaucoma. The presence of a disc hemorrhage (LR, 12; 95% CI, 2.9-48) was highly suggestive of glaucoma, but the absence of a hemorrhage was nondiagnostic (LR, 0.94; 95% CI, 0.83-0.98). At the commonly used cutoff for high IOP (≥22), the LR was 13 (95% CI, 8.2-17), while lower IOP made glaucoma less likely (LR, 0.65; 95% CI, 0.55-0.76). We found no studies of screening examinations performed by generalist physicians in a routine setting. CONCLUSIONS AND RELEVANCE Individual findings of increased CDR, CDR asymmetry, disc hemorrhage, and elevated IOP, as well as demographic risk factors of family history, black race, and advanced age are associated with increased risk for POAG, but their absence does not effectively rule out POAG. The best available data support examination by an ophthalmologist as the most accurate way to detect glaucoma.

Incidence and characteristics of acute intraocular inflammation after intravitreal injection of bevacizumab: a retrospective cohort study

OBJECTIVE To determine the incidence and characteristics of acute intraocular inflammation after intravitreal bevacizumab injections from a tertiary care retinal practice. DESIGN Retrospective cohort study. PARTICIPANTS A consecutive series of patients who had received bevacizumab injections performed by a single surgeon. METHODS We reviewed the records of all patients with severe anterior chamber inflammation and (or) vitritis after bevacizumab injections. RESULTS A total of 693 bevacizumab injections were performed on 193 eyes of 173 patients between June 2006 and March 2008. There were a total of 9 cases of acute intraocular inflammation for an incidence of 1.30% (95% CI: 0.69%-2.47%). All patients had a worse visual acuity at the end of follow-up than on injection day. The mean loss of vision was 6.1 lines of Snellen visual acuity; one patient developed inflammation-induced glaucoma which required surgical intervention. CONCLUSIONS Intravitreal injection of bevacizumab is associated with a low but significant risk of acute intraocular inflammation and may result in significant visual loss.

Comparison of retinal nerve fibre layer measurements from time domain and spectral domain optical coherence tomography systems

OBJECTIVE To compare retinal nerve fibre layer (RNFL) thickness measurements acquired using spectral domain (SD) and time domain (TD) optical coherence tomography (OCT) systems. STUDY DESIGN Prospective clinical study. PARTICIPANTS Twenty eyes of 20 healthy volunteers. METHODS All patients underwent 3 sets of circular OCT scans around the optic disc using both a TD OCT system, and a new SD OCT system. RNFL thickness measures within each of 4 quadrants, as well as overall mean RNFL thickness, were compared. Bland-Altman plots were also used to assess agreement. RESULTS Using the RTVue-100, RNFL measurements in the superior quadrant were, on average, 20 microm greater than those obtained from the Stratus (151.8 microm vs 131.7 microm, p< 0.0001). RNFL measures within other quadrants and overall mean RNFL thickness were not significantly different between systems. Bland-Altman plots indicated large differences between Stratus and RTVue-100 for all variables, with 95% limits of agreement spanning clinically important ranges of >50 microm for all RNFL variables. CONCLUSIONS Significant differences exist between RNFL measurements obtained from the TD and SD OCT systems used in this study. These related, but distinct, technologies are not interchangeable. Further studies will be required to allow for appropriate clinical use of new SD OCT systems.

Ocular and systemic safety of bevacizumab and ranibizumab in patients with neovascular age-related macular degeneration.

Purpose of review This study reviews differences in both ocular and systemic safety between intravitreal bevacizumab and ranibizumab in the setting of neovascular age-related macular degeneration. Recent findings Serious adverse events associated with either bevacizumab or ranibizumab injections are generally rare. However, acute intraocular inflammation (AII) tends to occur more frequently following bevacizumab injection. Systemic absorption of bevacizumab is greater than with ranibizumab, and many studies have shown an increased risk of systemic adverse events in patients receiving bevacizumab compared with those receiving ranibizumab. Summary Although rare, adverse events with off-label use of bevacizumab are more common than with ranibizumab. Continued study into long-term safety of the two agents is warranted.

Acute-onset floaters and flashes

Posterior vitreous detachment is the most common cause of acute-onset floaters or flashes of light. Its prevalence is 24% among adults aged 50–59 years, increasing to 87% among people older than 80 years.[1][1] In posterior vitreous detachment, the vitreous shrinks and detaches from the retina

Quality of life amongst American vs. Canadian patients with retinal diseases.

Purpose of review To compare health-related quality of life (HRQoL) in American vs. Canadian populations suffering from retinal diseases. Recent findings A search of Medline was conducted according to a strategy that combined the MeSH heading ‘retinal diseases’ with either of ‘quality of life’ as a MeSH or ‘utility’ as a keyword. We included studies of American or Canadian patients using any of the National Eye Institute 25-item visual functioning questionnaire (NEI-VFQ-25), visual function index (VF-14), short form health survey (SF-36), or utility to assess HRQoL. A total of 22 studies with American patients and five with Canadian patients were found. There was no significant HRQoL difference found between the American and Canadian patients for any of the HRQoL instruments (P = 0.14–0.80); however, for all instruments mean HRQoL correlated positively with mean visual acuity in the better-seeing eye (P < 0.001). Summary On the basis of a review of the currently published literature, we were unable to detect significant differences in HRQoL between American and Canadian patients. Further research into the topic is necessary.

Anaesthetic plus dilating gel improves pupil dilation for cataract surgery

OBJECTIVE To evaluate the efficacy of a combination anaesthetic plus dilating gel (ADG) on pupil dilation (PD) and corneal anaesthesia (KA) compared to traditional preoperative pharmacotherapy for cataract surgery. DESIGN Prospective, noninferiority study. METHODS We studied 20 consenting adults who experienced unilateral cataracts and underwent routine cataract surgery, receiving the traditional preoperative pharmacologic regimen in the operated eye (control eye): diclofenac 0.1%, gentamicin 0.3%, cyclopentolate 1%, phenylephrine 2.5%, and tropicamide 1% 60 and 20 minutes prior to surgery. They then received tetracaine 0.5% and povidone-iodine 5% 10 minutes prior to surgery; and were given tetracaine 0.5%, povidone-iodine 5%, and lidocaine 2% gel 1 minute prior to surgery. Epinephrine 0.1%, 1 cc per 500 mL bag of balanced saline salt solution was administered during surgery. The nonoperated eye (study eye) received tetracaine 0.5%, povidone-iodine 5%, and 0.35 cc ADG gel (phenylephrine 10%, tropicamide 1%, diclofenac 0.1%, and lidocaine 2%) 60 and 10 minutes prior to surgery. PD and KA were measured at baseline, at 30 minutes, and at 5 minutes prior to surgery, and at 5 minutes after surgery. RESULTS There was no difference in PD (p = 0.2634) or KA (p = 0.6058) between the study eyes and the control eyes at baseline. Preoperatively, greater mydriasis was achieved in the study eye (7.95 ± 0.91 mm vs 7.17 ± 1.25 mm; p < 0.0001). There was no significant difference in preoperative KA between the study and control eyes (1.5 ± 2.2 mm vs 1.4 ± 2.1 mm; p = 0.77). CONCLUSIONS The combination ADG for preoperative preparation of cataract patients achieves at least equivalent dilation and corneal anaesthesia as the current preoperative pharmacologic regimen.

Patterns and causes of epiphora referrals to a tertiary oculoplastic practice

OBJECTIVE To report the causative factors and surgical candidacy of patients referred to an oculoplastic surgery clinic for the complaint of epiphora. DESIGN Prospective observational study. PARTICIPANTS Consecutive patients (n = 159) referred to a tertiary care oculoplastic surgery clinic over a 12-month period for the complaint of epiphora. METHODS The causative factor most responsible for tearing was determined based on clinical examination by the principal investigator, who was blinded to referral source. Patients were considered surgical candidates with a diagnosis of significant nasolacrimal duct obstruction, lid malposition, or pump dysfunction. The primary outcome was the percentage of referrals that were surgical candidates, classified by referral source. RESULTS The most common cause of tearing was nasolacrimal duct obstruction, occurring in 53 of 159 (33%) patients. The percentage of surgical candidates was highest in referrals from ophthalmologists (82%), followed by optometrists (67%) and family physicians (55%; p = 0.011 for difference between ophthalmologists and family physicians). CONCLUSIONS Epiphora may be because of a variety of causes, some of which are amendable to surgical treatment. In the absence of an obvious cause, a trial of lubrication by the family physician is warranted before referral being made to an oculoplastic surgeon.

Orbital compartment syndrome in a burn patient without aggressive fluid resuscitation.

Abstract Introduction: Orbital compartment syndrome may rarely occur in the setting of burns where therapy includes aggressive fluid resuscitation. Case: We report a case of bilateral orbital compartment syndrome in a 13-year-old male, with superficial facial burns secondary to hydrobromic acid, who did not receive aggressive fluid resuscitation. The patient was treated successfully with bilateral lateral canthotomy and cantholysis. Comment: Facial burns may lead to orbital compartment syndrome without aggressive fluid resuscitation, likely due to excessive leakage of fluid and protein into the orbit combined with an inflammatory reaction.