Extraocular Muscle Volumetry for Assessment of Thyroid Eye Disease.

BACKGROUND: In this study we evaluate the diagnostic accuracy of extraocular muscle volumetry in detecting thyroid eye disease and to compare the results with simple measurements of maximal medial rectus (MR) diameter. METHODS: Cross-sectional study that included 47 eyes of 47 patients with thyroid eye disease and 47 healthy controls. Patients underwent slitlamp examination and imaging consisting of computed tomography scans. Image segmentation and volume measurements were performed by 2 independent researchers. Intraobserver and interobserver reliability testing was also conducted. RESULTS: Total extraocular muscle volume was 7.31 ± 1.88 cm3 and medial volume was 2.38 ± 0.73 cm3 in the study group. In this group, the maximum measured diameter of the MR was 6.67 ± 0.35 mm. MR volume was statistically associated with maximum MR diameter (r = 9.78; P < 0.001). Both MR volume and maximum MR diameter measurements showed good predictive efficacy as shown using receiver operator characteristic curve analysis. CONCLUSIONS: Complications of thyroid eye disease are often sight threatening, and timely diagnosis is crucial for the management of the entity and its sequelae. The results of this study imply that simple measurements of maximum MR diameter are sensitive enough to establish diagnosis.

Association between HPV detection in swab samples and tissue specimens and ophthalmic pterygium recurrence.

PURPOSE: To investigate the presence of HPV on the ocular surface after surgical excision of HPV infected pterygia and the possible correlation of HPV with pterygium postoperative recurrence. MATERIALS AND METHODS: Both exfoliative pterygium swab samples and respective tissue specimens were received and analyzed with real-time PCR for the detection of HPV-infected pterygia. In addition, swab samples from patients that had HPV-infected pterygia with no recurrence after 1 year of follow-up, as well as swab samples from patients with healthy conjunctiva, were analyzed. RESULTS: Forty eyes with pterygium of 40 patients and 40 eyes with normal conjunctiva were included in the study. HPV virus was detected in the tissue specimens of 11 patients (27.5%) and in the swabs of 9 patients (22.5%). The HPV subtypes detected were 33, 39, 45, 56, 59, 66, and 68. The swab test had sensitivity of 81.82% and 100% specificity. In 15 (43%) patients, a bare sclera technique was used for pterygium removal and eleven of these patients showed recurrence of the disease. Surgical excision with use of autologous conjunctival graft was performed in twenty patients and five of them had recurrence. Patients with recurrent disease were 12.41 times more likely to have an HPV-infected pterygium (p = 0.031). Furthermore, from the 11 HPV positive patients, six had no recurrence, 1 year after surgery. In five of them, a swab sample was taken from the site of the surgical excision 1 year after surgery and real-time PCR was negative for HPV presence. CONCLUSION: Persistence of HPV infection seems to be correlated with postoperative pterygium recurrence. Further investigation with the use of the minimally invasive proposed swab technique may contribute in the understanding of pterygium pathogenesis and in the development of a more efficient treatment planning.

Ex vivo orbital volumetry using stereology and CT imaging: A comparison with manual planimetry.

OBJECTIVES: To evaluate the applicability of stereology and planimetry in orbital volume measurements using computed tomography (CT) and to compare the results between the two measurements. METHODS: Experimental study using sheep craniums for CT imaging. Water filling measurements were performed, as the validation technique. Quantification techniques were also evaluated in five human subjects. To examine the proportion of agreement among measurements, we tested intra- and inter-observer agreement. RESULTS: For stereology customization, a 1/8 systematic sampling scheme was considered as optimal; this resulted in a low coefficient of error (2.59 %) and low measurement time (1.9 mins). In sheep craniums, mean volume measured by water displacement, planimetry and stereology was 17.81 ± 0.59 cm3, 17.87 ± 0.68 cm3 and 17.54 ± 0.49 cm3, respectively. Total volumes, obtained by stereology, were highly correlated with the water-filling method (r=0.893; p = 0.001) and a paired t-test showed significant difference between methods (t=3.047; p = 0.014). Planimetry results displayed a high correlation with the water-filling method (r=0.957; p ≈ 0.001) but no statistically significant difference was found (p = 0.154). Mean difference using planimetry and stereology was 0.332 ± 0.322 cm3. In human subjects, using stereology, the estimated volume ranged between 18.57 cm3 and 19.27 cm3, and the mean orbital volume was 19.05 ± 0.50 cm3 with CE=3.75 ± 0.16 %. Mean measure time was 2.1 ± 0.1 mins. CONCLUSIONS: Stereological measurements were superior to manual planimetry in terms of user effort and time spent. Stereology sampling of 1/8 was successfully applied in human subjects and yielded a strong correlation with manual planimetry. KEY POINTS: • Stereology can be applied to measure the orbital volume using computed tomography. • Stereological measurements display high correlation with gold standard planimetry and combine low coefficient of error (2.59%) with low measurement time (1.9 min). • Stereology is superior in terms of user effort and time spent.

Non-Invasive Ocular Rigidity Measurement: A Differential Tonometry Approach.

PURPOSE: Taking into account the fact that Goldmann applanation tonometry (GAT) geometrically deforms the corneal apex and displaces volume from the anterior segment whereas Dynamic Contour Tonometry (DCT) does not, we aimed at developing an algorithm for the calculation of ocular rigidity (OR) based on the differences in pressure and volume between deformed and non-deformed status according to the general Friedenwald principle of differential tonometry. METHODS: To avoid deviations of GAT IOP from true IOP in eyes with corneas different from the "calibration cornea" we applied the previously described Orssengo-Pye algorithm to calculate an error coefficient "C/B". To test the feasibility of the proposed model, we calculated the OR coefficient (r) in 17 cataract surgery candidates (9 males and 8 females). RESULTS: The calculated r according to our model (mean ± SD, range) was 0.0174 ± 0.010 (0.0123-0.022) mmHg/µL. A negative statistically significant correlation between axial length and r was detected whereas correlations between r and other biometric parameters examined were statistically not significant. CONCLUSIONS: The proposed method may prove a valid non-invasive tool for the measurement method of OR, which could help in introducing OR in the decision-making of the routine clinical practice.

INTRA-SCLERAL PARATHALAMUS IMPLANT: EFFICACY AND SAFETY IN RABBIT EYES.

PURPOSE: A variety of anti-glaucomatous shunt designs have been proposed so far. This study evaluates the feasibility of a novel shunt design, the intra-scleral parathalamus implant (IPI), in a rabbit eye model. METHODS: Ten healthy albino rabbits were included. Measurements of the IOP, using TonoPenXL, as well as ocular rigidity (OR) and aqueous outflow facility (AO), using a previously described methodology, were performed in both eyes of each animal. Subsequently, the IPI was implanted at the left eye of all animals whereas the right eye served as control. Measurements of IOP were repeated at weekly intervals for 2 months postoperatively whereas measurements of OR and AO were repeated at the 1st and 2nd postoperative week. RESULTS: The IOP decreased significantly whereas the AO increased significantly postoperatively at the operated eyes. A significant postoperative decrease in OR was also recorded at the operated eyes. Respective differences at the fellow eyes were statistically not significant. Two animals developed postoperative complications and were excluded from follow-up. CONCLUSIONS: Results imply that the implantation of the IPI is feasible in rabbit eyes with significant favorable effects on the IOP, AO and OR.

Evaluation of iridociliary and lenticular elasticity using shear-wave elastography in rabbit eyes.

INTRODUCTION: A previous study has employed shear-wave ultrasound elastographic imaging to assess corneal rigidity in an ex-vivo porcine eye model. This study employs the same modality in vivo in a rabbit eye model in order to assess lens, ciliary body and total ocular rigidity changes following the instillation of atropine and pilocarpine. METHODS: Ten non-pigmented female rabbits were examined. Measurements of the lens, ciliary body and total ocular rigidity as well as lens thickness and anterior chamber depth were taken with the Aixplorer system (SuperSonic Imagine, Aix-en-Provence, France) with the SuperLinear™ SL 15-4 transducer in both eyes at baseline as well as after pilocarpine and atropine instillation. The IOP was also measured with the TonoPen tonometer. RESULTS: Changes in rigidity in the examined areas following atropine instillation were statistically not significant. Ciliary body rigidity was significantly increased whereas lens and total ocular rigidity were significantly reduced following pilocarpine instillation. The decrease in lens rigidity following pilocarpine was significantly associated with the respective increase in ciliary body rigidity. CONCLUSIONS: Shear-wave ultrasound elastography can detect in vivo rigidity changes in the anterior segment of the rabbit eye model and may potentially be applied in human eyes, providing useful clinical information on conditions in which rigidity changes play an important role, such as glaucoma, pseudoexfoliation syndrome or presbyopia.

Anterior chamber angle evaluation with ultrasound biomicroscopy and optical coherence tomography in eyes implanted with a Crystalens.

This study employs optical coherence tomography (OCT) and ultrasound biomicroscopy (UBM) imaging as well as optical aberrometry to examine correlations between the anterior chamber angle aperture and visual acuity for near vision as well as coma along the horizontal and vertical axes in eyes implanted with an accommodative intraocular lens (Crystalens). A retrospective comparative consecutive case series of 22 eyes of 11 patients (5 males) uneventfully implanted with a Crystalens. Eyes with signs of posterior capsular opacification were excluded. All eyes were examined with 40 MHz UBM (Ellex Eyecubed) and spectral-domain OCT (Zeiss Visante). The angle aperture along the horizontal and vertical meridians was recorded based on the software of the systems. The coma root mean square (RMS) scores for the horizontal and vertical meridians were also recorded with the iTrace aberrometer. The anterior chamber angle was significantly wider along the horizontal axis compared with the vertical axis by UBM (46.37° and 44.20°, respectively) and by OCT (46.79° and 43.58°, respectively) (p = 0.02 in both cases, paired-samples t test). The correlations between the logMAR-converted Jaeger near vision score and the horizontal or vertical angle apertures was not statistically significant. Horizontal coma RMS was significantly inversely correlated with the horizontal angle aperture (r = -0.45, p = 0.03 and r = -0.39, p = 0.04 by OCT and UBM, respectively). Measurement of the horizontal angle aperture by the modalities used may represent an anatomical and clinical predictor of the optical aberrations induced by the Crystalens.

Ocular rigidity: biomechanical role, in vivo measurements and clinical significance.

Ocular rigidity (OR) refers to the relationship between pressure and volume changes in the eyeball. Since the description of the differential tonometry method for the calculation of an OR coefficient by Friedenwald, several other methodologies have been proposed to measure OR, including the anterior chamber manometry, axial length (AL) changes, measurement of pulse amplitude and fundus pulse, ultrasound elastography and evaluation of corneal hysteresis. However, most of these methodologies suffer from deficiencies, such as invasive nature, poor accuracy or reproducibility or technical complexity. Nevertheless, it is possible that OR affects the pathogenesis and clinical course of a variety of ocular conditions, including glaucoma, age-related macular degeneration, presbyopia, corneal changes following refractive surgery as well as the accuracy of IOP measurements by many tonometers. Thus, the future development of non-invasive and easy-to-use methodologies for the accurate measurement of OR in the every-day practice would be clinically important.

Optical Coherence Tomography Angiography (OCTA) of the eye: A review on basic principles, advantages, disadvantages and device specifications.

Optical Coherence Tomography Angiography (OCTA) is a relatively new imaging technique in ophthalmology for the visualization of the retinal microcirculation and other tissues of the human eye. This review paper aims to describe the basic definitions and principles of OCT and OCTA in the most straightforward possible language without complex mathematical and engineering analysis. This is done to help health professionals of various disciplines improve their understanding of OCTA and design further clinical research more efficiently. First, the basic technical principles of OCT and OCTA and related terminology are described. Then, a list of OCTA advantages and disadvantages, with a special reference to blood flow quantification limitations. Finally, an updated list of the basic hardware and software specifications of some of the commercially available OCTA devices is presented.

Ocular trauma, visual acuity related to time of referral and psychosocial determinants, during COVID­19 pandemic: A prospective study.

The aim of the present study was to explore the associations between visual outcomes of ocular injury patients in a tertiary hospital unit with clinical and demographic variables and to evaluate the psychosocial impact of the injury on the patients. An 18-month prospective study of 30 eye-injured adult patients was conducted in the General University Hospital of Heraklion, Crete, a tertiary referral hospital. All severe eye injury case information was prospectively collected between February 1, 2020 and August 31, 2021. Best corrected visual acuity (BCVA) was labelled not poor (>0.5/10 or >20/400 on the Snellen scale, <1.3 in LogMAR scale) and poor (≤0.5/10 or ≤20/400 on the Snellen scale, ≥1.3 on the LogMAR equivalent). Data regarding participants' perceived stress levels, by using Perceived Stress Scale 14 (PSS-14), were collected prospectively, one year after study end. Out of 30 ocular injury patients selected, 76.7% were men and most of them were self-employed and private or public sector workers (36.7%). Not poor final BCVA was related to not poor initial BCVA [odds ratio (OR) 1.714; P=0.006]. No statistical associations were found between visual outcome and demographic or clinical factors, but not poor final BCVA was associated with improved self-reported psychological condition of the sufferers, as examined by a questionnaire sheet developed to collect information for study purpose (8.36/10 vs. 6.40/10; P=0.011). No patient reported job loss or changed work status following the injury. Not poor initial BCVA was a significant predictor for not poor final visual outcomes (OR 1.714; P=0.006). Patients with not poor final BCVA expressed higher levels of positive psychology (8.36/10 vs. 6.40/10; P=0.011) and less fear of eye injury repetition (64.0 vs. 100.0%; P=0.286). Not poor final BCVA was associated with low PSS-14 scores one year after study end (77.3 vs. 0.0%, P=0.003). Collaboration between ophthalmologists, mental health professionals and primary care team may be important in order to help patients to cope with the psychosocial burden sequel to eye trauma.

Clinical and Social Features of Patients with Eye Injuries Admitted to a Tertiary Hospital: A Five-Year Retrospective Study from Crete, Greece.

Eye injuries are a major cause of visual disability worldwide and may present a burden to both quality of life of the sufferers and healthcare services. The aim of this study was to extract and triangulate information on the demographic, clinical, and social features of eye-injured adult patients admitted to a tertiary hospital in Greece. The design was a five-year retrospective study of eye-injured adult patients, admitted to the General University Hospital of Heraklion, Crete (GUHH), the single tertiary referral hospital on the island. Drawing the profile of eye-injured patients may add to future health planning. Data collected from 1 January 2015 to 31 December 2019, such as sociodemographic features and clinical information, were extracted. One hundred twenty-eight patients were included. Of those, there was no available information on activity during injury for 6 patients, 78 (60.9%) had work-related ocular injuries, and 44 (34.4%) had non-work-related ocular injuries. Patients with no current formal employment, those who were retired, and formally unemployed and manual force workers had the higher rates of work-related injuries. The most common work-related injuries were closed globe injuries, specifically contusions, while ruptures and penetrating wounds were the most frequent of the open globe injuries. Within the univariate analyses, work-related eye injuries were significantly associated with male gender, middle age, and the place related to daily work activity. Determinants of poor final visual acuity (VA) were the initial VA, the type of injury (p < 0.0001), the distance of the place of residence from the hospital, and the time to hospital admission (p < 0.013). In a multivariate analysis, referred patients and those with open globe injuries arrived at hospital after a two-hour interval compared with those who were not referred and those with closed globe injuries (p ≤ 0.05). A reduction in the time to hospital admission deserves further attention. The interconnection of community and health system services through a capacity increase and networking needs further research in order to obtain targeted and viable access for eye-injured patients.

Nonsurgical management of silent sinus syndrome with hyaluronic acid gel.

A 44-year-old woman was referred with 3 mm of left enophthalmos and a deep superior sulcus. She was diagnosed 6 months earlier with silent sinus syndrome and had undergone a left middle-meatal antrostomy with improvement of her hypoglobus but not of her enophthalmos and superior sulcus deformity. Two milliliters of Restylane SubQ (Q-Med AB, Uppsala, Sweden) was injected as a single bolus in the intraconal and extraconal posterior orbit via a standard transcutaneous inferotemporal approach using a primed green 21-gauge needle. Immediate reduction of enophthalmos by approximately 2 mm and superior sulcus improvement were noted. This remained stable at 6 months. The symptoms and signs of silent sinus syndrome can be effectively corrected with this minimally invasive nonsurgical option. To our knowledge, the use of hyaluronic acid gel for the treatment of enophthalmos in silent sinus syndrome has not been previously reported.

Unexpected finding in ocular surface trauma: a large intraorbital foreign body (bullet).

Sometimes intraorbital foreign bodies lead to unexpected findings. A 16-year old boy was referred due to ocular surface trauma. A conjunctival laceration was detected at the level of the left caruncle with associated left exotropia, reduced adduction as well as a preretinal hemorrhage along the nasal periphery of the fundus. A blow-out fracture of the medial orbital wall was suspected and a CT scan of the orbits was scheduled which revealed the presence of a large intraorbital foreign body. The removal of the intraorbital foreign body (which proved to be a bullet) and precautionary laser photocoagulation along the nasal periphery of the left eye were performed. Ocular surface trauma may reveal unexpected findings, such as an intraorbital foreign body, requiring investigation by a CT scan.

Individualized dosimetry in Ru-106 ophthalmic brachytherapy based on MRI-derived ocular anatomical parameters.

PURPOSE: To estimate ocular geometry-related inaccuracies of the dosimetric plan in Ru-106 ophthalmic brachytherapy. METHODS AND MATERIALS: Thirty patients with intraocular lesions were treated with brachytherapy using a Ru-106 plaque-shell of inner radius of 12 mm. Magnetic resonance imaging was employed to determine the external scleral radius at tumor site and the tumor margins. A mathematical model was developed to determine the distance between the external sclera and the internal surface of the plaque associated with the tangential application of the plaque on the treated eye. Differences in delivered dose to the tumor apex, sclera and tumor margins as derived by considering the default eye-globe of standard size (external sclera radius = 12 mm) against the individual-specific eye globe were determined. RESULTS: The radius of external sclera at the tumor site was found to range between 10.90 and 13.05 mm for the patient cohort studied. When the patient specific eye-globe/tumor geometry is not taken into account, the delivered dose was found to be overestimated by 8.1% ± 4.1% (max = 15.3%) at tumor apex, by 1.5% ± 2.8% (max = 5.7%) at anterior tumor margin, by 16.6% ± 7.5% (max = 36.4%) at posterior tumor margin and 8.1% ± 3.8% (max = 13.2%) at central sclera of eyes with lower than the default radius. The corresponding dose overestimations for eyes with higher than the default radius was 13.5% ± 4.3% (max = 22.3%), 1.5% ± 2.8% (max = 5.7%), 12.6% ± 4.5% (max = 20.0%), and 15.1% ± 5.0% (max = 24.4%). CONCLUSIONS: The proposed patient-specific approach for Ru-106 brachytherapy treatment planning may improve dosimetric accuracy. Individualized treatment planning dosimetry may prevent undertreatment of intraocular tumors especially for highly myopic or hyperopic eyes.

Monocanalicular intubation in external dacryocystorhinostomy.

PURPOSE: To examine the feasibility of monocanalicular intubation in external dacryocystorhinostomy (EX-DCR). METHODS: Monocanalicular intubation using the mini-Monoka tube (S1-1500u, FCI Ophthalmics, Marshfield Hills, MA, U.S.A.) was performed in 18 patients undergoing EX-DCR. The tube was placed at the superior canaliculus in 16 cases and at the inferior canaliculus in 2 cases and was removed 3 months postoperatively. All cases were followed for at least 6 months postoperatively. RESULTS: The mini-Monoka was well tolerated in all patients. One case of spontaneous tube dislocation and 2 cases of presumed tube migration were recorded on the 15-day interval. Success rates on the 6-month interval were 88.88% (16/18), 94.44% (17/18), and 66.66% (12/18), concerning patency upon irrigation, resolution of mucopurulent epiphora, and resolution of watery epiphora, respectively. CONCLUSIONS: Monocanalicular intubation using mini-Monoka in EX-DCR is safe and effective. The technique may have advantages over bicanalicular intubation, such as easier insertion and removal, easier probing and irrigation though the unintubated canaliculus and, more importantly, less risk of punctal or corneal damage.

Late-onset inverse Bell's phenomenon after upper eyelid trauma.

Bell's phenomenon evaluation is an important part of preoperative patient assessment for eyelid surgeries. Inverse Bell's phenomenon is a rare manifestation, usually observed in the early postoperative period following ptosis restoration surgeries, in pathological conditions, and in a small proportion of normal population. In the current case report, a 6-year-old girl presented with late-onset posttraumatic inverse Bell's phenomenon, 6 months after facial trauma with posttraumatic lagophthalmos. Rehabilitative blepharoplasty for the correction of lagophthalmos led to the restoration of inverse Bell's phenomenon 3 months postoperatively. Potential causative mechanisms are discussed for this late-onset manifestation of inverse Bell's response.

COVID-19 in Ophthalmology. Current Disease Status and Challenges during Clinical Practice.

Purpose: The novel coronavirus disease 2019 (COVID-19) has raised a global public health concern. The purpose of this review is to summarize the evidence currently available on COVID-19 for its ocular implications and manifestations from both pathogenetic and clinical standpoints. Methods: For this narrative review, more than 100 relevant scientific articles were considered from various databases (PubMed, Google Scholar, and Science Direct) using keywords such as coronavirus outbreak, COVID-19, ophthalmology, ocular symptoms. Results:Daily healthcare both from patient and physician perspective, as well as on some guidelines regarding prevention and management have dramatically changed over the last few months. Although COVID-19 infection mainly affects the respiratory system as well as the gastrointestinal, cardiovascular, and urinary systems, it may cause a wide spectrum of ocular manifestations. Various challenges have to be faced to minimize exposure for both patients and physicians. Conclusion:The risk of COVID-19 infection should be considered and medical care should be prioritized for urgent cases. Appropriate management for patients with chronic cases that may result in adverse outcomes should not be neglected, while patients that can be monitored remotely should be identified.

Changes in peri-ocular anatomy and physiology in pseudoexfoliation syndrome (Review).

Pseudoexfoliation syndrome (PEX) is characterized by the deposition of proteinaceous material in the anterior ocular segment (resulting in ophthalmic pathologies such as glaucoma and increased risk of complications in cataract surgery), but also by several systemic manifestations. The involvement of peri-ocular tissues in PEX, including the eyelid skin, lacrimal gland, conjunctiva, orbital fat and vessels, as well as the optic nerve, has been reported by several previous studies. The peri-ocular effects of PEX include the development of eyelid laxity, conjunctival chalasis, tear film abnormalities, pronounced orbital fat atrophy in response to the administration of prostaglandin analogues in pseudoexfoliative glaucoma, deficient orbital vascular supply and biomechanical changes in both the eyeball and the optic nerve. These effects may have important clinical implications, including increased difficulty in cataract surgery, ocular surface disease and eyelid margin malpositions.

Causes, occupational risk and socio-economic determinants of eye injuries: a literature review.

PURPOSE: This review provides literature views on ocular trauma, with emphasis on common causes of injury, occupational risk, socio-economic factors, management peculiarities and some implications on overall care approach, from prevention to treatment. METHODS: A literature search was performed using key words in PubMed to extract the most relevant articles on ocular injuries, from an occupational point of view. Seventeen relevant articles were included out of seventy-two. Eight relevant articles were found from the references of the articles included and were also added. The total number of articles for this systematic search analysis was twenty-five. Collected information was tabulated in the Appendix. RESULTS: Most of the included publications were original articles. Many studies were retrospective and cross-sectional with a satisfactory rate of participant recruitment when reported. Most of eye injuries occurred in the workplace. Common eye injuries were due to foreign bodies and corneal abrasions. High-risk occupations included welders, farmers, metalworkers and grinding, construction and manufacturing workers. Most of the injuries could be preventable by using suitable protective eye devices (PED) but appropriate protection is a more complex process than it appears. CONCLUSIONS: Findings of this review showed that it is compulsory to inform people about the risk and consequences of eye injuries. Eye care services should be designed keeping in mind geo-epidemiologic trauma etiology patterns and local health system capacity. Issues of adherence to prevention measures remain object of knowledge dissemination, educational planning and cultural appraisal. Modernizing equipment and respecting workplace regulations are tasks that deserve continuous attention.

Ultrasound Elastography in Ocular and Periocular Tissues: A Review.

Ultrasound elastography has become available in everyday practice, allowing direct measurement of tissue elasticity with important and expanding clinical applications. Several studies that have evaluated pathological and non-pathological tissues have demonstrated that ultrasound elastography can actually improve the diagnostic accuracy of the underlying disease process by detecting differences in their elasticity. Ocular and periocular tissues can also be characterized by their elastic properties. In this context, a comprehensive review of literature on ultrasound elastography as well as its current applications in Ophthalmology is presented.