Improving outcomes by combining septoplasty with primary external dacryocystorhinostomy.

PURPOSE: External dacryocystorhinostomy (EXT-DCR) is the gold standard in the treatment of acquired nasolacrimal duct obstruction. Intranasal pathology can compromise the success of primary and revision external dacryocystorhinostomy EXT-DCR procedures. Nasal septal deviations resulting in unfavorable anatomy are an identified cause of DCR failures. In this study, we examine the causes of failure in our patient population and propose that concomitant treatment of septal deviations at the time of primary EXT-DCR can decrease the rate of revision surgery. MATERIALS AND METHODS: Retrospective review of patients who had undergone an EXT-DCR. RESULTS: Over a five year period, 12 EXT-DCR failures were identified and 8 were directly attributable to nasal septal deviations. Revision surgery was successful in all 8 cases after correction of the nasal septal deviation. A second cohort of patients was identified who had undergone primary EXT-DCR and septoplasty concomitantly. Eight consecutive patients underwent the combined procedure for a total of 10 EXT-DCR and 8 septoplasties. The only failure was due to a common canalicular obstruction (90% success rate for the combined approach). CONCLUSIONS: As a result of our findings, we believe that treating nasal septal deviation at the time of the initial surgery can help minimize the need for revision surgery.

Neurovascular Changes Associated With the Water Drinking Test.

PURPOSE: The water drinking test (WDT) is currently used to temporarily elevate intraocular pressure (IOP) and predict peak IOP in glaucoma. This study investigates neurovascular changes associated with WDT in normal subjects. METHODS: The effect of WDT (1 L in 5 min) on IOP, mean brachial blood pressure, heart rate, and pattern electroretinogram was assessed within the next hour in 16 healthy subjects (mean age: 33.5±7.9 y). As a control, testing was repeated in the same subjects without WDT 1 week later. RESULTS: Compared with control, WDT resulted in significant peak changes of the following parameters compared with baseline: IOP: +1.7±1.8 mm Hg after 30', mean brachial blood pressure: +3.9±6.3 mm Hg after 15'; heart rate: -9.2±9.8 bpm after 15', pattern electroretinogram latency: +2.1±0.9 ms after 15'. CONCLUSIONS: In addition to IOP elevation, WDT was associated with significant changes of hemodynamic parameters and retinal ganglion cell function in young healthy subjects. As these represent risk factors for glaucoma, their assessment upon WDT might increase its predictive power for glaucoma development.

Pattern electroretinogram progression in glaucoma suspects.

PURPOSE: To prospectively monitor progressive changes of retinal ganglion cell function in early glaucoma using the pattern electroretinogram (PERG). METHODS: Fifty-nine patients enrolled as glaucoma suspects were observed untreated over an average of 5.7±1.4 years, during which they were tested with PERG (PERGLA paradigm) and standard automated perimetry (SAP) 2 times per year. PERG amplitude and phase were normalized for physiological age-related changes, and linear regressions fitted to the data to calculate progression slopes (signal), slope SE (noise), and corresponding signal-to-noise ratios (SNR=slope÷SE). Linear regressions were also used to fit SAP global indices mean deviation (MD) and pattern standard deviation (PSD). RESULTS: On average, progression slopes of PERG amplitude/phase were skewed toward negative values, their mean being significantly (P<0.01) different from zero. In contrast, mean slopes of SAP-MD and PSD were not significantly different from zero. SNRs were higher for PERG than SAP (P<0.01). A substantial number of eyes displayed significant (P<0.05) progression of PERG amplitude (15% to 20%) or PERG phase (16% to 25%). Fewer eyes displayed significant progression of SAP-MD (0% to 2%) or SAP-PSD (4% to 8%). CONCLUSIONS: The PERG displayed clear longitudinal loss of signal (diminished amplitude, phase delay, or both) in a substantial number of eyes of patients, indicating progressive deterioration of retinal ganglion cell function. Progression of SAP global indices MD and PSD was found in a relatively smaller number of eyes. It remains to be established whether PERG progression has predictive value for developing visual dysfunction.

Head-down posture induces PERG alterations in early glaucoma.

PURPOSE: To probe susceptibility of retinal ganglion cells (RGC) to physiological stressors associated with moderate head-down body tilt in patients with suspicion of glaucoma or early manifest glaucoma (EMG). METHODS: One hundred nine subjects with best corrected visual acuity (BCVA) ≥ 20/20 and no disease other than glaucoma [glaucoma suspects (GS)=79, EMG=14, normal controls (NC)=16 and comparable age range were tested. Noncontact intraocular pressure (IOP), pattern electroretinogram (PERG), and brachial blood pressure/heart rate measurements were performed in 3 consecutive conditions (∼0038 min apart): seated (baseline), -10-degree whole body head-down tilt (HDT), and seated again (recovery). PERG amplitude and latency, IOP, and systolic/diastolic blood pressures, heart rate, calculated mean central retinal artery pressure, ocular perfusion pressure, and systolic/diastolic perfusion pressures were evaluated. RESULTS: During HDT, IOP significantly (P<0.001) increased in all groups approximately to the same extent (approximately 20%). PERG amplitude did not change in NC but decreased significantly (P<0.001) in patients (GS, -25%, EMG -23%). PERG phase become delayed in NC (-1.6%, P=0.04) but more so in patients (GS, -2.7%, P<0.001; EMG, -6.0%, P<0.001). The proportion of patients with PERG alterations significantly (P<0.05) exceeding those occurring in age-adjusted and baseline-adjusted NC were, GS: amplitude 20%, phase 15%; EMG: amplitude 14%, phase 50%. All measures recovered baseline values after HDT. CONCLUSIONS: Moderate HDT induces temporary worsening of RGC function in a subpopulation of GS and EMG patients. This noninvasive protocol may help disclose abnormal susceptibility of RGCs in a subset of the patients at risk of glaucoma.

The PERG in diabetic glaucoma suspects with no evidence of retinopathy.

OBJECTIVE: To better understand the role of diabetes mellitus on retinal ganglion cell function of glaucoma suspects. METHODS: Eighteen diabetic glaucoma suspects (GSD) without retinopathy (type-2, n=16, type-1, n=2) and 156 age-matched glaucoma suspects (GS) without diabetes were tested with steady-state pattern electroretinogram (PERG, PERGLA paradigm, Ophthalmology 2004,111:161) as surrogate measure of retinal ganglion cell function. Results were compared with previously published data of 48 similarly aged normal controls (NC). All subjects (NC, GS, GSD) had small refractive errors and corrected visual acuity > or =20/25. RESULTS: The mean PERG amplitude of both GS and GSD was significantly (P<0.01) smaller than that of age-matched NC. The mean PERG amplitude of GSD patients was significantly (P<0.05) smaller than that of GS accounting for individual differences in age, visual acuity, visual field defect, and intraocular pressure. The mean PERG phase did not differ between GS and GSD. CONCLUSIONS: In agreement with previous studies, our results show that on average, GS have reduced PERG amplitude compared with NC. PERG amplitude is further reduced in GSD compared with nondiabetic GS with otherwise comparable ophthalmologic and systemic conditions.