Treatment of Painful Bullous Keratopathy with Accelerated Transepithelial Crosslinking

This study evaluated the safety and efficacy of Bowman's membrane electrocautery in blind painful eyes with bullous keratopathy not amenable to corneal transplantation. Eleven eyes of 11 subjects with painful bullous keratopathy and poor visual potential who underwent electrocautery of Bowman's membrane at a tertiary referral ophthalmology clinic were reviewed retrospectively. Subject demographics and preoperative and postoperative data were collected, including description of pain, slit lamp biomicroscopy, best corrected visual acuity, topical medication use, and complications. Efficacy of the procedure on pain reduction, bullae resolution, and topical medication use were assessed at post-operative visits. Safety was also evaluated based on any complications. Bowman's membrane electrocautery effectively resolved bullae in all eyes examined up to 6months postoperatively; however, 2 eyes had recurrence by 1year. Mean age at the time of surgery was 69.8years and mean duration of follow-up was 15.4months. Pain reduction was achieved in all eyes at 1month, but 1 subject had pain recurrence by 6months and another by 1year. The median number of drops per day decreased from 6 preoperatively to 1.7 at 6months. Two subjects who had underlying advanced ophthalmic disease had a mild reduction in vision. Bowman's membrane electrocautery is a safe and minimally invasive procedure for the management of painful bullous keratopathy in eyes with low vision potential and not amenable to corneal transplantation. Duration of effect appears to last at least 6months and up to 3years post-procedure.

Central corneal thickness in children—does it help or hinder our evaluation of eyes at risk for glaucoma?

Objective: To evaluate the effect of corneal cross-linking (CXL) on quality of life in patients with bullous keratopathy. Material and Methods: The study was designed as prospective, comparative, single-center and nonrandomized cohort. Ten patients with painful bullous keratopathy to whom CXL was applied were included in the study group. Ten consecutive patients with painful bullous keratopathy who didn't accept CXL were admitted as the control group. Besides routine ophthalmic examinations, SF-36 (Short Form-36) questionnaire was also performed to all patients at baseline. All examinations were repeated at first, 3rd, 6th and 12th months. Results: A significant improvement in ''Physical Functioning'' and ''Vitality'' subscales starting from the first month after CXL, continuing up to the postoperative 6th month (p=0.04, p=0.01, respectively) was achieved. An improvement in ''Bodily Pain'' subscale was achieved starting at the 3rd month after CXL, and continued until the 6th month (p=0.01, p=0.01, respectively). Unfortunately, there was a deterioration in ''Physical Functioning'', ''Bodily Pain'', and ''Vitality'' subscales starting from the 6th month, with statistically significant variations between the 6th and the 12th months (p=0.02, p=0.02, p=0.02, respectively). In the control group, there was a significant deterioration in ''Physical Functioning'', ''Bodily Pain'', ''General Health'', and ''Social Functioning'' subscales between baseline and the 12th month (p=0.02, p=0.04, p=0.02, p=0.03, respectively). Conclusion: CXL may be useful in the treatment of bullous keratopathy when waiting for keratoplasty, particularly in patients with intense pain by temporarily improving the quality of life.

Objective To observe the clinical treatment of anterior corneal stromal puncture combined with amniotic membrane patching in bullous keratopathy and rsistent epithelial defects and recurrent corneal erosion. Methods Retrospective case series study. Analysis retrospectively the treatment of bullous keratopathy in 39 cases, 40 eyes in Tangshan ophthalmic hospital from January 2013 to January 2016 which implement anterior corneal stromal puncture combined with amniotic membrane patching. Among them, in 26 cases with bullous keratopathy in 26 eyes including 7 eyes with cataract surgery for glaucoma, 3 eyes with absolute glaucoma period, 5 eyes with vitrectomy, 6 eyes with ocular trauma, 5 eyes with neovascular glaucoma. In 8 cases with rsistent epithelial defects in 8 eyes including 4 eyes with acid burn, 4 eyes with alkali bum. In 5 cases with recurrent corneal erosion in 6 eyes including 2 eyes with Lattice malnutrition, 4 eyes with ocular trauma, 16 cases with patients of diabetes. All patients had obvious pain, tears irritation symptom. When the treatment was invalid after conservative therapy. The anterior corneal stromal puncture combined with amniotic membrane patching was carried out, to observe the eye irritation, corneal epithelial healing,edema of matrix and postoperative visual acuity, and so on. Results Forty eyes in 39 cases were relieved 3 days after the surgery, all patients had no pain and irritation symptoms after amniotic suture removal in 7-10 days. The corneal epithelium was repaired under the slit lamp microscope. One month the bullous keratopathy was recurrence after operation. In one eye which was cured with second anterior corneal stromal puncture. Follow up for 3-6 months, there were no recurrence of keratopathy, corneal epithelium was smooth, no edema, corneal stromal puncture area shallow layer to form a layer of uniform opacitas. The postoperative visual acuity: 22 eyes had no change before and after operation, 18 eyes improved partly. Conclusions The bullous keratopathy patients, resistant epithelial defects and recurrent corneal erosion caused by various factors are treated with anterior corneal stromal puncture combined with amniotic membrane patching, the eye symptom is obviously improved. Not only save the eyeball, but also improve vision on some of the eye. The anterior corneal stromal puncture combined with amniotic membrane patching is a simple, effective and reliable treatment method. Key words: Anterior corneal stromal puncture; Keratopathy; Amniotic membrane patching

Aim. The objective of the current study was to evaluate the reduction of edema and pain with the use of elastic stockings. Method. The effect of walking on a treadmill for 50 minutes in the evening wearing elastic compression stockings on pain and edema was evaluated in a prospective randomized crossover clinical trial. In Assessment 1, the legs of participants were measured by volumetry at 7:00 a.m. and they were asked to perform their normal daily activities and to return at 4:00 p.m. Forty-two legs of 21 female patients with ages of the participants ranged from 32 to 72 years with signs and symptoms of chronic venous disease. The sizes of the legs of all patients were evaluated by water displacement volumetry and a visual analog scale was used to assess pain. Results. After walking for 50 minutes on the treadmill, the volume reduced (paired t-test: p value < 0.03). In relation to pain, there was a reduction in pain after the treadmill session using the elastic stocking (Wilcoxon signed rank test: p value < 0.007). Conclusion. The reduction of edema and pain of the legs during the course of the day can be accomplished with the use of elastic stockings, as well as walking.

Corneal cross-linking (CXL), a corneal strengthening procedure, is known to alter anterior stroma swelling behavior and is one of the treatment modalities of bullous keratopathy (BK). There are multiple studies published on the role of CXL in the treatment of BK. These articles had heterogeneous study population, different protocols used, and variable conclusions. This systematic review aimed to determine the role of CXL in the treatment of BK. The primary outcomes considered were changes in central corneal thickness (CCT) after 1, 3, and 6 months of CXL. The secondary outcome measures were changes in visual acuity, corneal clarity, subjective symptoms, and complications after CXL. We included randomized control trials (RCTs), observational and interventional studies, and case series with reports of more than 10 cases in this review. In RCTs, the mean pre-CXL CCT (794.0 ± 178.5 μm) in the intervention group (n = 37), decreased at 1 month (750.9 ± 154.3 μm) followed by a subsequent increase, but this difference was not significant during the 6-month follow-up (P- value 0.28, 0.82, and 0.82 at 1, 3, and 6 months, respectively). In noncomparative clinical studies (n = 188), the mean pre-CXL CCT (794.0 ± 178.5 μm) decreased at 1 month (710.9 ± 127.2 μm, P < 0.0001). Seven of the 11 articles included in the review reported no significant improvement in vision with CXL. The initial improvement in corneal clarity and clinical symptoms was not sustained. Current evidence suggests that CXL has short-term efficacy in the treatment of BK. More RCTs with high-quality evidence are needed.

Primary open-angle glaucoma as a causal factor for circadian disruption: Living by the clock, in alignment with external time cues is an important condition for human health and well-being. Periodic changes in the ambient light serve as a key factor to synchronize the endogenously generated circadian rhythms. The retina perceives the photic signals and transmits them to the central body clock, the suprachiasmatic nuclei (SCN), via the retinohypothalamic tract. Primary open angle glaucoma (POAG) is an optic neuropathy, in which disease progression can be monitored by assessing damage to the retinal ganglion cells (RGCs) (Pérez-Rico et al., 2010; Feigl et al., 2011; Kankipati et al., 2011). Damage of retinal ganglion cells, particularly of intrinsically photosensitive RGCs (ipRGCs), is also one of the causes of circadian disruption. Pathophysiological mechanisms of POAG are complex, including elevated intraocular pressure (IOP), which adds mechanical stress, causing damage, dysfunction, and death of the RGCs (Figure 1). Glaucoma progression affects both image-forming and non-image-forming visual functions of RGCs. A central role of ipRGCs is to convey non-image-forming photic information to the clock. Their damage reduces light signaling to the SCN. Already in early stages of glaucoma, ipRGCs are dysfunctional (Pérez-Rico et al., 2010; Feigl et al., 2011; Kankipati et al., 2011).Figure 1: Melatonin potential to counteract complex circadian alterations with aging, neurodegeneration, specifically in glaucoma.ipRGCs: Intrinsically photosensitive retinal ganglion cells; SNPs: single nucleotide polymorphisms.As RGCs are progressively altered, and non-image-forming function is affected, circadian rhythms are disrupted, sleep is impaired, and mood is altered (Graticelli et al., 2015; Gubin et al., 2019, 2021). Circadian rhythm alterations are found in POAG as compared to age-matched healthy peers (Gubin et al., 2019). Circadian disruption worsens in advanced POAG (Gubin et al., 2019, Neroev et al., 2020), correlating to the increasing loss of ipRGCs with disease progression (Obara et al., 2016). Circadian rhythms also change with increasing age. Age-dependent circadian alterations are not necessarily related to retinal damage, as photic transduction to the central clock is not always compromised. When they are related to retinal damage, they can be due to either neurodegenerative ipRGCs damage, or to ipRGC damage caused by increased mean or deregulated circadian IOP. The intriguing principal difference between the presence or absence of retinal damage in aging is that the reduced light transmitted to the SCN by damaged ipRGCs phase-delays circadian rhythms, but ipRGC-uncompromised aging is commonly associated with phase-advanced circadian rhythms (Gubin et al., 2019). Since individual differences in sensitivity to light, and/or in endogenous melatonin production may interfere with this theoretical modeling, the search for specific genetic factors that may determine such individual differences constitutes a promising approach. In conditions where photic entrainment is compromised, not only is the alignment with external time cues altered, so can be the variability of overt physiologic functions. We showed that large inter-individual variability obscured the circadian IOP rhythm in POAG (Neroev et al., 2020). Circadian IOP rhythms had specific alterations manifested in advanced, but not in mild POAG, which were associated with the progressive damage and dysfunction of RGCs. In patients with RGCs' global loss volume above 15%, as assessed by high-definition optical coherence tomography, the 24-hour IOP rhythm peaked during the night, whereas in patients with stable POAG and a two-eye mean RGCs' global loss volume less than 10%, the IOP peaked predominantly during the daytime. Misalignment between circadian rhythms in body temperature and IOP increased as a function of global loss volume loss. Higher nocturnal IOP in POAG may adversely affect the disease state, fostering damage to RGCs (Neroev et al., 2020). Depending on individual genetic factors, these changes may manifest themselves to a different degree. Individual clock properties depend on numerous genetic factors, comprising clock genes and melatonin receptor genes, melatonin nuclear receptor 1b (MTNR1b) in particular, which may account for large individual differences in light sensitivity. Our pilot study of gene polymorphisms in POAG showed that the D-allele of the Angiotensin-converting enzyme holding a deletion of the 16th intron Alu repeat was significantly associated with alterations of the circadian IOP rhythm. It may also account for the resistance to IOP-lowering therapy (Neroev et al., 2020). Endogenous melatonin production in primary open-angle glaucoma: Glaucoma patients experienced reduced post-illumination pupil response (Kankipati et al., 2011) and reduced nocturnal melatonin suppression by light (Pérez-Rico et al., 2010). Clinical evidence for changes in the timing and mean values of endogenous melatonin production in POAG was also evident (reviewed in Gubin et al., 2021): in POAG, salivary melatonin can be lower than in age-matched controls without POAG; even greater alterations were observed In advanced stages of the disease. The main alteration concerned the time of maximal secretion of melatonin. Such altered melatonin production in POAG and other neurodegenerative pathologies can stem from different factors, including diminished light signaling due to a reduced sensitivity to light. The presence of certain gene polymorphisms can increase the susceptibility of carriers to these factors. We investigated 24-hour profiles of salivary melatonin under controlled lighting conditions and analyzed several clock genes and polymorphisms of the melatonin receptor gene MTNR1b (Gubin et al., 2021). Patients diagnosed with stable POAG had unaltered circadian rhythms of salivary melatonin and body temperature, which peaked at the anticipated time. Circadian rhythms of both variables were delayed, however, in patients diagnosed with advanced POAG (Gubin et al., 2019, 2021). Their 24-hour mean value and circadian amplitude of melatonin were also reduced (Gubin et al., 2021). Analysis of selected polymorphisms in clock and melatonin receptor genes revealed that these changes were observed specifically in carriers of the MTNR1B rs10830963 G-allele with advanced POAG. Overt changes of circadian phenotypes in POAG patients occur when several factors are present in combination: for example, when RGC loss exceeds a certain threshold in carriers of those genotypes, known to be associated with a prolonged duration of melatonin production. The MTNR1B rs10830963 G-allele is mainly known for its association with an elevated fasting glucose and the risk of type 2 diabetes, but it is also listed as a factor predicting POAG independently of diabetes (Shen et al., 2016), a fact supporting the assumption that melatonin may have pleiotropic physiological functions in the development of POAG. Melatonin to counteract non-image-forming visual function deterioration in primary open-angle glaucoma: To enhance circadian entrainment, morning light therapy and evening melatonin administration can both be effective. While studies aimed at estimating the merit of morning light therapy or outdoor light exposure in POAG are lacking, some studies provide evidence for a beneficial effect of exogenously administered melatonin in glaucoma and neurodegenerative pathologies (González Fleitas et al., 2021; Gubin et al., 2021). Melatonin transmits environmental light signals, thus facilitating the synchronization of peripheral clocks. It can thus mitigate several conditions such as glaucoma and its progression: disruption of circadian rhythms, compromised sleep, and mood (Tosini et al., 2012; Gubin et al., 2021) (Figure 1). Melatonin improves internal synchronization, ameliorating circadian alignment between local (IOP) and systemic (temperature) circadian rhythms (Gubin et al., 2021), which were progressively desynchronized with greater RGCs loss in POAG (Neroev et al., 2020). Melatonin is produced endogenously with a pronounced 24-hour rhythm governed by the SCN. Peak production occurs at night. Its specific timing may differ among individuals. Exact endogenous factors that predetermine these differences are not known but may include single nucleotide polymorphisms within candidate genes or melatonin receptors that influence sensitivity to light. Melatonin receptors (MTNR1B) are widespread in numerous brain regions. Their structure may determine the specific response to (both endogenous and exogenous) melatonin. We investigated the effect of oral melatonin administration (daily at 10:30 p.m. for 90 days) on the circadian rhythms of IOP, body temperature, and the pattern electroretinogram in patients diagnosed with stable or advanced POAG, also assessing effects on sleep and mood (Gubin et al., 2021). Melatonin administration increased the stability of the circadian body temperature rhythm, improving its alignment with the circadian IOP rhythm. Melatonin decreased IOP to a different extent at different times of the day and decreased the standard deviation of IOP with statistical significance. Larger changes were found in patients with initially higher 24-hour mean values of IOP. Melatonin improved RGCs function in patients with advanced POAG by increasing the amplitude of pattern electroretinogram that correlated positively with the degree of RGCs loss. Melatonin had more pronounced positive effects on sleep and mood in patients with advanced POAG, who had greater damage of their RGCs. Taken together melatonin has the potential to restore disrupted circadian rhythms in POAG. Its systemic effect is distinct from its local effect on the retinal circadian rhythms. Similar to light exposure, physiological effects of melatonin depend on the time of its administration. Personalizing melatonin administration in terms of its timing and dosing, accounting for the genetic profile, is expected to further refine its multiple benefits. Melatonin may provide beneficial effects in POAG stemming from both its ability to reduce IOP and its potential to prevent RGC damage derived from mechanisms of neurodegeneration (Hardeland, 2021) (Figure 1). These effects may not only mitigate circadian disruption but also improve other aspects of health and well-being. Circadian alignment may strengthen human physiological functions and help slow neurodegeneration. The choice of an optimal melatonin dosing, however, is not yet clear (Hardeland, 2021). Consideration of the best timing should be based on internal circadian parameters and on genes that may account for personal differences in melatonin efficacy. Concluding remarks: In assessing disruptions in the non-image-forming visual system in POAG patients, one needs to discriminate between different situations. There may be complex, non-specific changes in circadian rhythms with age. Changes related to neurogenerative disease, including Alzheimer's disease, Parkinson's disease, and POAG, might promote alterations in neural structures: SCN, pineal, retina. Changes specific to POAG include additional RGC damage caused by the elevated IOP, together with abnormal circadian patterns of physiological variables such as IOP, body temperature, pattern electroretinogram, and melatonin (Figure 1). The circadian IOP pattern with relatively higher values during the resting span may foster harmful effects of IOP on RGCs, since tissue sensitivity may vary depending on circadian time (Neroev et al., 2020). Numerous candidate gene polymorphisms may play a role, alone or in combination with others, affecting the susceptibility to POAG itself (as a primary pathology of vision), or POAG-associated alterations of circadian rhythms, sleep, and mood, linked to non-visual pathways. To answer this question, clinical data combined with circadian profiles of melatonin and other physiological variables, chronotype questionnaires, sleep and mood information, to be checked against single nucleotide polymorphisms databases, should be collected on large cohorts. Constructive collaboration among ophthalmologists, chronobiologists, and geneticists is therefore advocated. The present work was supported by the Russian Foundation for Basic Research (grant No. 19-015-00329) (to DG), and by Government of Tyumen District, Decree of 20.11.2020 No. 928-rp (to DG). The authors have no proprietary or commercial interest in any materials discussed in this article.

To assess the effect of overnight wear of a contact lens-based sensor (CLS) for monitoring of 24-hr intraocular pressure (IOP) fluctuations on central corneal thickness (CCT). Changes in the CCT, mid-peripheral corneal thickness and central corneal radius (CCR) during overnight CLS wear in 20 eligible patients with ocular hypertension or established glaucoma were prospectively studied using ultrasound pachymetry and topography. Corneal thickness and CCR changes were evaluated from pre-to-postsleep, with the fellow eye as control. Paired t-test or Wilcoxon signed-rank test was used as appropriate and with α = 0.05. Relationship between the IOP profile recorded by the CLS and the pre-to-postsleep corneal thickness differences was assessed using the Spearman correlation coefficient. After CLS wear, mean CCT had changed from 523 to 537 μm (p = 0.015) in the study eye and from 518 to 522 (p = 0.206) in the fellow eye (n = 15). There was no difference in CCT change between eyes (p = 0.075). There were no statistically significant changes in horizontal or vertical CCR in either eye (p > 0.05 for all). No correlation was found between the pre-to-postsleep differences in the CLS signal and the pre-to-postsleep differences in ultrasound CCT measurements (p = 0.974). The continuous IOP monitoring does not appear to be affected by differences in corneal thickness that occur during overnight CLS wear, although the CLS did induce some corneal swelling. This effect was not statistically significantly different from the control eye and does not seem to influence the CLS IOP profile.

To examine the effects of topical steroid instillation on central corneal thickness in eyes with bullous keratopathy (BK). Retrospective case series METHODS: Consecutive patients with BK who did not wish to receive corneal transplantation and were treated with 0.1% betamethasone eyedrops were included. Patients with BK treated with 5% sodium chloride (hypertonic saline) eyedrops served as controls. Central corneal thickness (CCT),best-corrected visual acuity (BCVA), intraocular pressure (IOP), BK etiology,and clinical courses from medical records were retrospectively reviewed. We compared the two groups for differences in CCT, BCVA and IOP before treatment and 2 weeks, 1 month, and 3 months after treatment. Eighteen eyes of 18 patients who were treated with betamethasone and 18 eyes of 18 patients who were treated with hypertonic saline were included. There was no significant difference in CCT between the two groups before treatment. The reduction of CCT in the betamethasone group was significantly larger than in the hypertonic saline group at 2 weeks (p = 0.002), 1 month (p = 0.02), and 3 months (p = 0.001) after treatment. Complications such as infectious keratitis and IOP rise did not occur during the observation period. Topical steroid instillation reduced central corneal thickness in eyes with BK.

Objective To observe the clinical effect of corneal intralamellar thermo cauterization combined with radiotomy of corneal nerve and patch grafting of amniotic membrane to treat bullous keratopathy. Methods Twenty-eight cases (28 eyes) of bullous keratopathy with obvious pain and poor vision were selected, including 16 cases after cataract surgery combined with intraocular lens implantation, 3 cases after cataract surgery, 3 cases after cataract surgery combined with anti-glaucoma surgery,2 cases after anti-glaucoma surgery, 1 case with absolute stage of glaucoma, 2 cases after ocular injury, 1 case after vitrectomy. They were all performed with corneal intralamellar thermo cauterization combined with radiotomy of corneal nerve and patch grafting of amniotic membrane. All cases were followed up for 6～32 months after operation. Results The symptoms of pain disappeared in 25 cases, relieved in 3 cases. The visual acuity was improved in 8 cases, no improved in 20 cases. Amniotic membrane was absorbed or desquamated at 5-45 days postoperatively. Corneal bulla disappeared in 26 cases and area of bulla was reduced in 2 cases. Edema of corneal stroma was also decreased in 28 cases. Following up for 6 to 32 months, there was no recurrence of symptoms or bulla and no occurrence of complications. Conclusions Corneal intralamellar thermo cauterization combined with radiotomy of corneal nerve and patch grafting of amniotic membrane is effective to alleviated clinical symptom of bullous keratopathy with poor visual function. Key words: Bullous keratopathy; Intralamellar thermo cauterization; Radiotomy; Amniotic membrane

The Ocular Response Analyzer (ORA) is a new instrument that measures the corneal biomechanical response (corneal hysteresis, CH) to rapid indentation by an air jet. CH is the difference in applanation pressures (P1, P2) between the rising and falling phases of the air jet. The investigation had two parts: a characterization study and a validation study. In the characterization study, the purposes were to investigate the intraocular pressure (IOP)-dependence of CH and to characterize the performance of the ORA. In the validation study, the purposes were to investigate the association between CH and both age and central corneal thickness (CCT) and the agreement between ORA and Goldmann applanation tonometer (GAT) IOP measurements. For the characterization study, data were collected from 105 untreated subjects (45 ocular hypertensive patients and 60 normal subjects; mean age, 60 years, range, 26-82). GAT and ORA measurements were performed before and after IOP lowering of one randomly selected eye with apraclonidine drops. The change in P1 and P2 (arbitrary units) in relation to change in GAT IOP was analyzed to calibrate the instrument. The relation between P1, P2, and CCT was explored and ORA IOP was derived from the analyses. For the validation study, ORA and GAT IOP and CCT were measured in 144 eyes of 144 untreated subjects (mean age, 58 years; range, 19-83). The characterization calculations were applied to the dataset and values of CH and ORA IOP were calculated. The relationship between CH and both subject age and CCT was determined. The associations between CH and CCT and between ORA and GAT IOPs, were investigated by linear regression analysis. The agreement between measuring devices was calculated. In the characterization study, P1 changed by 6.41 arbitrary units for every 1-mm Hg change in GAT IOP. CH (P1 - P2) changed by -1.60 arbitrary units for every 1-mm Hg change in GAT IOP. For each unit change in P2, P1 changed by 1.27 units. From this association a new IOP-independent corneal factor was derived [P1 - (P2/1.27)] and is termed the corneal constant factor (CCF; mm Hg). ORA IOP normalized for CCF was defined as P2 - CCF (mm Hg). The CCF (mm Hg) was associated with CCT (micrometers) and with age: CCF = [(0.036 . CCT) - (0.028 . age)] + 1.06 (adjusted r2 = 0.34; P < 0.0001 for CCT, P = 0.007 for age). Normalized ORA IOP measurements were not associated with CCT. GAT IOP was associated with CCT and CCF-more strongly with the latter: GAT IOP = (0.03 . CCT)+1.52 (r2 = 0.06, P = 0.002); GAT IOP = (0.65 . CCF) + 4.5 (r2 = 0.13, P < 0.0001). The mean difference (95% limits of agreement) between GAT and normalized ORA IOP was 0.1 (-6.6 to +6.8) mm Hg. The CCF describes an IOP-independent biomechanical property of the cornea that increases with thicker CCT and decreases with greater age. It is moderately strongly associated with CCT and yet explains more of the interindividual variation in GAT IOP than does CCT. Normalized ORA IOP measurements are not associated with CCT.

Purpose: Determine if anterior stromal puncture (ASP) has a more effective decrease in symptomatology (pain, photophobia, and foreign body sensation) compared to annular keratotomy (AK) in the treatment of painful bullous keratopathy (PBK) in patients with poor visual prognosis. Methods : Patients with PBK, refractory to combined medical treatment and poor visual prognosis were randomly assigned to one of two surgical procedures. Symptomatology, central corneal thickness (CCT), visual acuity (VA), and best corrected (BCVA) were evaluated with a 7-month follow up. Results: From 78 patients with PBK, 13 fulfilled inclusion criteria; ASP was performed to 7 and AK to 6 of them. There was improvement in the magnitude of symptoms in both groups; however, there was no difference when groups were compared. CCT showed a significant reduction from the basal, of 10.4% in the ASP group compared with a 9.6% increase in the AQ group (p=0.05). VA and BCVA in both groups were not modified. None of the groups presented complications related to the surgical procedures. Conclusions: In this clinical trial, we documented that ASP and AQ produce a similar improvement in the symptomatology of patients with PBK refractory to combined medical treatment and poor VA potential. The ASP group additionally presented a significant decrease in CCT. A longer follow-up period would be required to evaluate if this CCT reduction is able to modify the frequency of bullae development and symptoms relapse. Furthermore, the material used for ASP has a lower cost than the one used for AQ, which could represent an economic advantage for patients that attend our Hospital.

It is important to accurately measure intraocular pressure (IOP) in eyes with corneal endothelial dysfunction both before and after Descemet stripping with automated endothelial keratoplasty (DSAEK). Glaucoma is a common comorbidity in this population, and IOP elevation can worsen corneal edema. Additionally, preexisting glaucoma and steroid-responsive ocular hypertension are significant risk factors for graft rejection after DSAEK. Accurate tonometry is limited by variations in central corneal thickness (CCT) and corneal hydration that may affect corneal biomechanical properties. We analyzed CCT and IOP in eyes before and after DSAEK to determine whether changes in corneal biomechanics because of edema, grafted tissue, and subsequent stromal deturgescence affect IOP measurement. A retrospective chart review was performed on 32 eyes from 31 patients with corneal edema secondary to Fuchs endothelial dystrophy, bullous keratopathy, or prior graft failure, or rejection that received uncomplicated DSAEK with no evidence of persistent corneal edema or steroid-induced ocular hypertension. IOP was measured by Tono-Pen XL, and CCT was measured by ultrasound pachymetry before and approximately 3 months after surgery. We used paired t tests to evaluate changes in CCT and IOP after DSAEK and linear regression to determine the relationship between CCT and IOP before and after surgery. CCT significantly decreased from 703 ± 82 to 650 ± 52 μm after DSAEK (P = 0.0026), but there was no significant change in measured IOP (16.7 ± 3.4 mm Hg preoperatively and 16.3 ± 4.1 mm Hg postoperatively; P = 0.61). There was no significant relationship between CCT and IOP before (slope = 0.10 ± 0.07 mm Hg/10 μm; r = 0.062; P = 0.17) or after (slope = 0.21 ± 0.14 mm Hg/10 μm; r = 0.072; P = 0.14) DSAEK. CCT is significantly reduced by DSAEK but remains well above the normal range. IOP remains near the preoperative level 3 months after DSAEK. Furthermore, no correction is required for Tono-Pen measurements of IOP in corneas thickened by edema secondary to endothelial dysfunction or by DSAEK.

Introduction: Glaucoma is characterised by structural damage to optic nerve head with corresponding visual field defects and often associated with increased Intraocular Pressure (IOP). It may be broadly classified as Primary Angle Closure Glaucoma (PACG) and Primary Open Angle Glaucoma (POAG). It is one of the leading causes of global blindness, and a major proportion occurs in Indian population. Aim: To study the correlation between pretreatment IOP and extent of visual field loss in PACG and POAG. Materials and Methods: A cross-sectional observational study was carried out in Regional Institute of Ophthalmology, Trivandrum, Kerala, India from April 2016 to May 2017. Newly diagnosed cases of PACG (25 patients-13 males, 12 females, mean age 58.72±10.07 years) and POAG (85 patients- 45 males, 40 females, mean age 60.28±10.42 years) underwent a detailed glaucoma evaluation which included IOP measurement with Goldmann applanation tonometer and visual field testing using Humphrey Field Analysis (HFA) 24-2 pattern. Mean Deviation (MD), Pattern Standard Deviation (PSD) and Advanced Glaucoma Intervention Score (AGIS) score was calculated from reliable visual field test result. All data were coded and entered in to statistical software, Statistical Package for Social Sciences (SPSS) version 16.0 for analysis. The correlation between pretreatment IOP and visual field loss in patients with PACG and POAG was determined by Pearson Correlation of Coefficient. Results: Amongst the total 110 patients of this study, 25 patients were of PACG while POAG were in 85 patients. A significant correlation between pre treatment IOP and the extent of visual field loss in PACG was noted. There was no significant correlation in POAG. Linear regression analysis demonstrated a significant positive correlation between IOP and AGIS score in PACG (Pearson correlation coefficient(r)=0.805, p&lt;0.001), not in POAG (r=0.026, p=0.816). Correlation between IOP and MD is statistically significant in PACG (r=0.812, p&lt;0.001) but not in POAG (r=0.058, p=0.597). The correlation between IOP and PSD is not statistically significant in both groups (p-value &gt;0.450). Conclusion: A significant correlation between IOP and visual field loss in PACG indicates that extent of visual field damage can be controlled by controlling IOP alone in PACG. The correlation between the pretreatment IOP and visual field loss in POAG is not statistically significant which agrees with the current proposed pathophysiology of optic neuropathy in which multiple factors influence in addition to IOP.

To compare intraocular pressure (IOP) control in eyes with or without clear corneal phacoemulsification following trabeculectomy. The study group included 30 eyes that underwent uneventful clear corneal phacoemulsification and foldable intraocular lens implantation following trabeculectomy without antimetabolites. Thirty eyes that had undergone filtering surgery without cataract extraction were selected as controls. Case and control groups were matched with respect to age, gender, IOP, number of glaucoma medications, glaucoma type (primary open-angle glaucoma/pseudoexfoliative glaucoma), trabeculectomy time and follow-up. Comparisons between the study and control groups (intergroup) and within the same group at different time-points (intragroup) were performed for IOP, glaucoma medications and bleb morphology. Success rates were investigated by Kaplan-Meier survival analysis and the factors influencing final success by logistic regression. Intraocular pressure (p = 0.04) and glaucoma medications (p = 0.001) increased during an average follow-up of 26.1 +/- 9.9 months in both groups. Intragroup differences became statistically significant after the 6-month visit, but intergroup differences remained insignificant. Bleb height decreased significantly following phacoemulsification in the study group (p = 0.017). Success rates decreased with time in both groups, with no intergroup difference (p = 0.46). The final success rate was negatively correlated with IOP and number of glaucoma medications used at the study entry, while there was a positive correlation between the baseline and final success rates. Trabeculectomy success decreased in a time-dependent manner in eyes with and without subsequent phacoemulsification. Uncomplicated clear corneal phacoemulsification was not found to have any additional unfavorable influence on IOP control in eyes with filtering blebs.