The KERATO Biomechanics Study 1: A Comparative Evaluation Using Brillouin Microscopy and Dynamic Scheimpflug Imaging.

PURPOSE: To assess the corneal biomechanical properties in normal individuals and patients with keratoconus using the Brillouin optical scanning system (Intelon Optics) (BOSS) and compare them with ultra-high-speed Scheimpflug imaging (Corvis ST; Oculus Optikgeräte GmbH). METHODS: Sixty eyes from 60 patients (30 normal and 30 keratoconus) were included in this prospective, single-center, comparative, non-interventional study. Corneal biomechanics were evaluated using the Corvis ST and the BOSS. With the BOSS, each corneal image was acquired three times, measuring 10 locations within an 8-mm diameter. Parameters extracted included mean, maximum, and minimum Brillouin shift. These 10 points were also grouped into superior, central, and inferior regions. BOSS repeatability was assessed using the coefficient of repeatability and coefficient of variation. Furthermore, normal individuals and patients with keratoconus were compared using the Corvis ST and BOSS. RESULTS: The BOSS exhibited good repeatability, with coefficient of repeatability ranging from 0.098 to 0.138 GHz for single points in normal individuals and 0.096 to 0.149 GHz for patients with keratoconus. Statistical analysis revealed significant differences between normal individuals and patients with keratoconus, indicating softer corneas in keratoconus, observed with both the Corvis ST and BOSS. Specifically, the BOSS showed significant differences in mean, inferior, and superior mean, maximum, and minimum Brillouin frequency shift (all P < .05), whereas the Corvis ST displayed highly significant differences in stiffness parameter at first applanation, stress strain index, deformation amplitude ratio, and inverse integrated radius (all P < .001). CONCLUSIONS: Corneal biomechanical measurements proved highly repeatable and effectively demonstrated significant differences between normal individuals and patients with keratoconus using both the BOSS and the Corvis ST. [J Refract Surg. 2024;40(8):e569-e578.].

Preoperative intravenous mannitol administration and its rationale before cataract surgery.

BACKGROUND: The purpose of this study is to assess the variations in anterior chamber depth (ACD), axial length (AXL), and intraocular pressure (IOP) in both phakic and pseudophakic eyes undergoing preoperative intravenous mannitol infusion. The study was conducted at the Ophthalmology Department of IRCSS Humanitas in Milan, Italy. This is a prospective and non-randomized study. METHODS: 40 patients with phakic eyes and 40 patients with pseudophakic eyes scheduled for cataract surgery in their fellow eye were included. Prior to the surgery, comprehensive ophthalmic examinations were conducted, including IOP measurement, and bilateral biometry performed with Anterion® (Heidelberg Engineering GmbH, 69,115, Heidelberg, Germany). All patients received intravenous infusion of mannitol before the surgery. One hour after cataract extraction, the patients underwent the same set of examinations. We analyzed the changes AXL, ACD and IOP in the eye opposite to the one that underwent surgery. RESULTS: The comparison between preoperative and postoperative parameters showed no differences in AXL (p = 0.34 and p = 0.53) and in ACD (p = 0.38 and p = 0.31) in the phakic and in the pseudophakic group, respectively. Instead, a statistically significant difference was found between the mean preoperative and postoperative IOP (p = 0.02) for the phakic group and (p = 0.03) for the pseudophakic group. CONCLUSIONS: The administration of mannitol does not lead to any changes in the ACD and AXL, regardless of whether the eyes are phakic or pseudophakic. However, there is a statistically significant reduction in IOP. Nonetheless, it is important to consider the various side effects associated with mannitol infusion.

Keratoconus and Corneal Ectasia with Relatively Low Keratometry.

INTRODUCTION: The study aims to demonstrate and estimate the prevalence of clinical corneal ectasia and keratoconus (KC) in patients with relatively low keratometry (low-K KC). METHODS: In a retrospective, analytical, and non-interventionist study, one eye was randomly selected from 1054 patients from the original Tomographic Biomechanical Index (TBIv1) study and the external validation (from Rio de Janeiro, Brazil, and Milan, Italy clinics). Patients were stratified into three groups. Group 1 included 736 normal patients, and groups 2 and 3 included 318 patients with clinical KC in both eyes, divided into low-K KC (90 patients) and high-K KC (228 patients), respectively. All patients underwent a comprehensive ophthalmological evaluation along with Pentacam and Corvis ST (Oculus, Wetzlar, Germany) examinations. Cases with maximum mean zone 3 mm keratometry (Kmax zone mean 3 mm) lower than 47.6 diopters (D) were considered as low-keratometry keratoconus, and cases with Kmax zone mean 3 mm higher than 47.6 D were regarded as high-keratometry keratoconus. RESULTS: Ninety (28.30%) of the 318 KC group presented ectasia with low-keratometric values (low-Kmax). The average age in the normal group was 39.28 years (range 6.99-90.12), in the low-Kmax KC group it was 37.49 (range 13.35-78.45), and in the high-Kmax KC group it was 34.22 years (range 12.7-80.34). Mean and SD values and median (range), respectively, of some corneal tomographic and biomechanical parameters evaluated from the low-Kmax KC group were as follows: Belin-Ambrósio enhanced ectasia display (BAD-D) 3.79 ± 1.62 and 3.66 (0.83-9.73); Pentacam random forest index (PRFI) 0.78 ± 0.25 and 0.91 (0.05-1); corneal biomechanical index (CBI) 0.58 ± 0.43 and 0.75 (0-1); TBI 0.93 ± 0.17 and 1 (0.35-1); and stiffness parameter at A1 (SP-A1) 86.16 ± 19.62 and 86.05 (42.94-141.66). CONCLUSION: Relatively low keratometry, with a Kmax lower than 47.6 D, can occur in up to 28.30% of clinical keratoconus. These cases have a less severe presentation of the disease. Future studies involving larger populations and prospective designs are necessary to confirm the prevalence of keratoconus with low keratometry and define prognostic factors in such cases.

Refractive surgical approaches to keratoconus: A systematic review and network meta-analysis.

Advancements in diagnostic methods and surgical techniques for keratoconus (KC) have increased non-invasive treatment options. Successful surgical planning for KC involves a combination of clinical science, empirical evidence, and surgical expertise. Assessment of disease progression is crucial, and halting the progression should be the focus if it is progressive. While surgeons used to rely on experience alone to decide the surgical method, comparing the network of primary factors, such as visual acuity, across studies can help them choose the most appropriate treatments for each patient and achieve optimal outcomes. Meticulous tabulation methods facilitate interpretation, highlighting the importance of selecting the correct surgical and rehabilitation approach based on each patient's condition and stage of the disease. We detail the outcomes of a comprehensive network meta-analysis comparing the effectiveness of various combined therapeutic refractive treatments for KC at identical stages of the disease, spanning 4 distinct follow-up intervals. Additionally, the comprehensive analysis suggests that for corneas with optimal best corrected visual acuity (BCVA) preoperatively (classified as regular), combining phakic intraocular lenses with intracorneal ring segments (ICRS) and corneal cross-linking (CXL) could offer the best therapeutic approach provided the disease stage does not exceed stage 3. For irregular corneas, although initial follow-ups show a significant difference in BCVA with surface ablation, longer-term follow-ups recommend combining surface ablation with ICRS and CXL, especially at higher stages.

Outcomes of Endoscopic Endonasal Dacryocystorhinostomy in Glaucoma Patients.

BACKGROUND: Anti-glaucoma eye drops have been investigated due to their production of fibrotic changes on the conjunctival surface, undermining the functioning of the upper lacrimal drainage system. We aimed to assess whether these effects may impair the effectiveness of endoscopic endonasal dacryocystorhinostomy (EE-DCR). METHODS: This is a single-center observational retrospective study on EE-DCR via a posterior approach. Resolution of epiphora and dacryocystitis were analyzed after 1 (T1) and 6-months (T2) from surgery. Surgical success was defined as anatomical (patency at irrigation, no recurring dacryocystitis) or complete (zeroing of Munk score). RESULTS: Twenty patients (32 sides) were enrolled. Preoperatively, 93.75% (n = 30/32) presented severe (Munk 3-4) epiphora and 68.75% (n = 22/32) recurrent dacryocystitis. At T1, 50.0% (n = 16/32) were referred with residual epiphora (Munk ≥ 1) and 18.75% (n = 6/32) dacryocystitis. At T2, 31.25% (n = 10/32) still complained of epiphora (Munk ≥ 1) and 6.25% (n = 2/32) dacryocystitis. Difference of outcomes at aggregate and paired timepoints (except for T1 versus T2) resulted in statistical significance (p < 0.05). At T2, 22 (68.75%) complete, 8 (25.0%) anatomical successes and 2 (6.25%) surgical failures were observed. CONCLUSIONS: Despite the chronic uptake of anti-glaucoma eye drops, EE-DCR guaranteed high rates of clinical relief from epiphora and remarkable decreases in the rates of recurrent dacryocystitis.

Persistent Conjunctival Chemosis after Lower Lid Blepharoplasty: A Comparison of Different Surgical Techniques.

Background: Conjunctival chemosis, a complication of lower blepharoplasty, can cause persistent discomfort and functional disturbances with worsening in the postoperative period following surgery. Methods: A review of the records of the lower blepharoplasty procedures carried out at the Humanitas Research Hospital, Rozzano, Milan, Italy was performed. Patients were categorized into two groups depending on the procedure performed: (1) transconjunctival blepharoplasty with the removal of the fatty lodges with canthopexy and (2) transcutaneous blepharoplasty with the removal of the fatty lodges with lateral canthoplasty. Each group was further divided into two more groups based on the surgical method used, that is either (a) cold blade and disposable cautery or (b) radiofrequency cut and coagulation and colorado tip (respectively 1a, 1b, 2a and 2b). All patients underwent a postoperative follow-up up to 24 months, which included an evaluation of cosmetic appearance, eyelid scarring and the severity of chemosis. The aim of the study was to investigate which of the surgical procedures causes a lower incidence of persistent type 3 conjunctival chemosis. Results: A total of 1047 patients who underwent lower lid blepharoplasty were included in the study. A total of 512 patients underwent transcutaneous blepharoplasty and 535 underwent the transconjunctival procedure. Among the first group of patients, 266 belong to group 1a and 246 to group 1b. In the second group, 264 were categorized as group 2a and 271 as group 2b. The incidence of type 3 chemosis in the transcutaneous blepharoplasty procedure with lateral canthoplasty was statistically significantly higher than in the transconjunctival approach, considering both the cold blade and the radiofrequency (p = 0.012, 0.010, 0.006, 0.004, respectively). Conclusions: A higher incidence of persistent type 3 conjunctival chemosis is associated with lateral canthus surgery and with the use of radiofrequency.

Low Rate of Postoperative Pterygium Recurrence in Patients under Treatment with Low-Dose Oral Doxycycline for Chronic Blepharitis: A First Report.

PURPOSE: Low doses of systemic doxycycline (LD-SD) inhibit angiogenesis and the expression of matrix metalloproteases, which are determinants of pterygium progression. This study aimed to compare the recurrence rate and visual outcome of pterygium excision in patients undergoing chronic treatment with LD-SD for chronic refractory blepharitis and LD-SD-naive patients. METHODS: A retrospective analysis of patients that underwent surgical excision and conjunctival graft apposition was conducted. Patients were divided in a TETRA group (under LD-SD treatment at the moment of surgery) and a control group. The main outcome was the rate of recurrence at 1 year postoperatively. Secondary outcomes were the comparisons of surface regularity, visual quality, and dry-eye symptoms at 6-week, 6-month, and 1-year follow-up in the two groups. RESULTS: The TETRA group showed a significantly lower rate of 1-year recurrence both in primary (p = 0.034) and recurrent (p < 0.001) pterygia. The best corrected visual acuity (BCVA), astigmatic error, corneal total root mean square (RMS), and ocular surface disease index (OSDI) significantly reduced during the follow-up in both groups. The surface asymmetry index and high-order aberrations (HOAs) significantly reduced only in the TETRA group. The final BCVA was significantly higher, while the OSDI score and total RMS and HOAs were significantly lower in the TETRA group compared to the control. CONCLUSIONS: Patients under treatment with LD-SD showed a lower rate of recurrence at 1-year follow-up compared to controls. These patients also experienced higher BCVA and surface regularity and less dry-eye symptoms.

Implantable loop recorder in Brugada syndrome: Insights from a single-center experience.

Background: This study aimed to investigate the characteristics and outcomes of patients diagnosed with Brugada syndrome (BrS) who underwent implantable loop recorder (ILR) insertion during routine clinical activity. Methods: We conducted a comprehensive screening of all consecutive patients diagnosed with BrS at our institution. We analyzed baseline clinical characteristics, arrhythmic findings, and outcomes. Results: Out of 147 BrS patients, 42 (29 %) received an ILR, 13 (9 %) underwent implantable cardioverter-defibrillator (ICD) placement, and 92 patients (63 %) continued regular cardiological follow-up. Patients who received an ILR had a higher prevalence of suspected arrhythmic syncope (43 % vs. 22 %, p = 0.012) and tended to be younger (median age 38 years, interquartile range 30-52, vs. 43 years, 35-55, p = 0.044) with a higher presence of SCN5A gene mutations (17 % vs. 6 %, p = 0.066) compared to those who continued regular follow-up. Additionally, compared to patients with an ICD, those with an ILR had a significantly lower frequency of positive programmed ventricular stimulation (0 % vs. 91 %, p < 0.001). During a median follow-up period of 14.7 months (4.7-44.8), no deaths occurred among the patients with ILR. Eight individuals (19 %) were diagnosed with arrhythmic findings through continuous ILR monitoring, primarily atrial fibrillation, and asystolic pauses. The median time from insertion to the occurrence of these events was 8.7 months (3.6-46.4). No adverse events related to ILR were reported. Conclusion: Continuous monitoring with ILR may facilitate the timely detection of non-malignant rhythm disorders in BrS patients with risk factors but without an indication for primary prevention ICD implantation.

Suboptimal visual outcome after femto-LASIK ablation in a high myopic patient.

A 28-year-old nurse had an aberration-free femto-laser in situ keratomileusis (LASIK) performed for her myopia of -6.25 -0.50 × 096 and -6.75 -0.50 × 175 in the right and left eye, respectively. Corrected distance visual acuity (CDVA) preoperatively was 20/16. Preoperatively, there were no abnormalities on Scheimpflug imaging, and a pachymetry of 585 µm was measured in both eyes. Flap thickness was 115 µm. The patient was quite nervous during the surgery. Since the surgery, her uncorrected distance visual acuity (UDVA) and CDVA are suboptimal at 20/30 and 20/20 in the right eye, and 20/20 and 20/16 in the left eye. 3 months postoperatively, there is a stable manifest refraction of +0.25 -1.25 × 030 and +0.25 -0.00 × 0. The keratometric astigmatism in the Scheimpflug imaging is 1.2 diopter (D) × 114 and 0.4 D × 78 in the right and left eyes, respectively (FIgures 1 and 2). Thinnest pachymetry is 505 µm and 464 µm in the right and left eye, respectively. Her wavefront analysis shows refraction in a 6 mm zone of -0.99 -1.22 × 32 and -0.91 -0.36 × 136. The cycloplegic refraction is 1.25 -1.00 × 023 and +1.00 -0.25 × 006 (Figures 3 and 4). What is the cause of the suboptimal visual outcome in this case? What would be your treatment strategy to improve visual outcome?

Camellin-Calossi Formula for Intraocular Lens Power Calculation in Patients With Previous Myopic Laser Vision Correction.

PURPOSE: To assess the performance of the Camellin-Calossi formula in eyes with prior myopic laser vision correction. METHODS: This was a retrospective case series. Patients included had a history of uncomplicated myopic laser vision correction and cataract surgery. The primary outcome measures were cumulative distribution of absolute refractive prediction error, absolute refractive prediction error, and refractive prediction error. These parameters were estimated post-hoc using the Camellin-Calossi, Shammas, Haigis-L, Barrett True-K with or without history, Masket, and Modified Masket formulas and their averages starting from biometric data, clinical records, postoperative refraction, and intraocular lens power implanted. RESULTS: Seventy-seven eyes from 77 patients were included. The Camellin-Calossi, Shammas, Haigis-L, Barrett True-K No History, Masket, Modified Masket, and Barrett True-K formulas showed a median absolute refractive error (interquartile range) of 0.25 (0.53), 0.51 (0.56), 0.44 (0.65), 0.45 (0.59), 0.40 (0.61), 0.60 (0.70), and 0.55 (0.76), respectively. The proportion of eyes with an absolute refractive error of ±0.25, 0.50, 0.75, 1.00, 1.50, and 2.00 diopters (D) for the Camellin-Calossi formula was 54.5%, 72.7%, 85.7%, 92.2%, 98.7%, and 100%, respectively. The cumulative distribution of the Camellin-Calossi formula showed the best qualitative performances when compared to the others. A statistically significant difference was identified with all of the others except the Haigis-L using a threshold of 0.25, with the Shammas, Modified Masket, and Barrett True-K at a threshold of 0.50 D and the Barrett True-K and Modified Masket at a threshold of 1.00 D. CONCLUSIONS: The Camellin-Calossi formula is a valid option for intraocular lens power calculation in eyes with prior myopic laser vision correction. [J Refract Surg. 2024;40(3):e156-e163.].

Outcomes in the Treatment of Subretinal Macular Hemorrhage Secondary to Age-Related Macular Degeneration: A Systematic Review.

Background: Subretinal macular hemorrhage (SRMH) secondary to age-related macular degeneration (AMD) is a relatively rare condition in ophthalmology characterized by blood collection between the neurosensory retina and the retinal pigment epithelium (RPE). Without prompt treatment, visual prognosis is poor. A plethora of treatment approaches have been tried over the past years ranging from intravitreal anti-vascular endothelial growth factor (anti-VEGF) monotherapy to direct subretinal surgery, with no conclusive superiority of one over the other. Materials and Methods: We conducted a systematic review of the outcomes and treatment modalities of SRMH from inception to 14 June 2022, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA). The level of evidence was assessed for all included articles according to the quality of evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. Results: A total of 2745 articles were initially extracted, out of which 1654 articles were obtained after duplicates were removed and their abstracts screened. A total of 155 articles were included for full-text review. Finally, 81 articles remained that fulfilled the inclusion criteria. Conclusions: Even though there are solid results supporting a variety of treatments for SRMH, the best treatment modality has still not been conclusively demonstrated and further research is needed.

Ophthalmological Manifestations in Inflammatory Bowel Diseases: Keep an Eye on It.

BACKGROUND AND AIMS: Inflammatory bowel diseases (IBD) are multifactorial chronic inflammatory disorders affecting the gastrointestinal tract. However, a broad spectrum of extraintestinal manifestations (EIMs) is associated with IBD, affecting several organs and systems, such as the skin, musculoskeletal and hepatobiliary systems, and, not least, the eye. Approximately 10% of IBD patients can develop ocular EIMs (O-EIMs) with a higher prevalence in Crohn's disease (CD). Eye-redness, photophobia, pain, and blurred vision are the common symptoms, with a wide rate of severity and clinical impact on the quality of life. This narrative review aims to summarize the prevalence, pathogenesis, and current evidence-based management of O-EIMs, underlying the importance of a holistic approach and specialties collaboration for a prompt diagnosis and treatment. METHODS: PubMed was searched up to December 2023 to identify relevant studies investigating the pathogenesis, epidemiology, and treatment of O-EIMs in IBD patients. RESULTS: The mechanisms underlying O-EIMs are partially unknown, encompassing immune dysregulation, shared antigens between the eye and the gut, genetic predisposition, and systemic inflammation driven by high levels of interleukins and cytokines in IBD patients. The complexity of O-EIMs' pathogenesis reflects in the management of these conditions, varying from topical and systemic steroids to immunomodulatory molecules and biologic therapy, such as anti-tumor necrosis factor (TNF)-alpha. A multidisciplinary approach is the backbone of the management of O-EIMs.