Semiautomated MRI-Based Method for Orbital Volume and Contour Analysis.

OBJECTIVE: The architecture of the orbital cavity is intricate, and precise measurement of its growth is essential for managing ocular and orbital pathologies. Most methods for those measurements are by CT imaging, although MRI for soft tissue assessment is indicated in many cases, specifically pediatric patients. This study introduces a novel semiautomated MRI-based approach for depicting orbital shape and dimensions. DESIGN: A retrospective cohort study. PARTICIPANTS: Patients with at least 1 normal orbit who underwent both CT and MRI imaging at a single center from 2015 to 2023. METHODS: Orbital dimensions included volume, horizontal and vertical lengths, and depth. These were determined by manual segmentation followed by 3-dimensional image processing software. MAIN OUTCOME MEASURES: Differences in orbital measurements between MRI and CT scans. RESULTS: Thirty-one patients (mean age 47.7 ± 23.8 years, 21 [67.7%]) females, were included. The mean differences in delta values between orbital measurements on CT versus MRI were: volume 0.03 ± 2.01 ml, horizontal length 0.53 ± 2.12 mm, vertical length, 0.36 ± 2.53 mm, and depth 0.97 ± 3.90 mm. The CT and. MRI orbital measurements were strongly correlated: volume (r = 0.92, p < 0.001), horizontal length (r = 0.65, p < 0.001), vertical length (r = 0.57, p = 0.001), and depth (r = 0.46, p = 0.009). The mean values of all measurements were similar on the paired-samples t test: p = 0.9 for volume (30.86 ± 5.04 ml on CT and 30.88 ± 4.92 ml on MRI), p = 0.2 for horizontal length, p = 0.4 for vertical length, and p = 0.2 for depth. CONCLUSIONS: We present an innovative semiautomated method capable of calculating orbital volume and demonstrating orbital contour by MRI validated against the gold standard CT-based measurements. This method can serve as a valuable tool for evaluating diverse orbital processes.

Orbital Development in Children with Retinoblastoma: An Imaging-Based Study.

PURPOSE: To examine whether children treated for Retinoblastoma (Rb) have impaired orbital development. METHODS: A retrospective case series was performed among children with Rb treated at a single medical center from 2004 to 2020. Orbital volumes and measurements were assessed by 3-dimensional image processing software. The main outcome measures were differences in orbital growth between Rb and non-Rb eyes assessed at last follow-up. RESULTS: Among 44 patients included (mean age 16.09 ± 18.01 months), a positive correlation between age and orbital volume was observed only in the uninvolved, healthy eyes (p = .03). In unilateral cases, orbital growth in the horizontal, vertical, and depth planes was smaller on the affected side compared to the healthy eyes (p < .05). Orbits that underwent enucleation showed decreased growth over time compared to those treated conservatively (p = .017). CONCLUSIONS: Orbital growth rate is slower in the orbits of children treated for Rb compared to healthy orbits. Enucleation negatively affects orbital growth.

Study in Patients With Unilateral Horner Syndrome Supports the Role of Müller's Muscle in the Eyelid-Dark Reflex.

Purpose: A previous study demonstrated upper eyelid retraction synchronized with pupil dilation following a transition from photopic to scotopic conditions. The current study aimed to evaluate the role of Müller's muscle as the efferent arm of this suggested reflex arc. Methods: A video scan of both eyes of patients with unilateral Horner syndrome was performed using optical coherence tomography infra-red mode to document the transition between photopic and scotopic conditions. The affected side with sympathetic denervation was the study group, whereas the contralateral unaffected side of the same patients served as the control group. The pupil diameter, upper eyelid margin-to-reflex distance 1, lower eyelid margin-to-reflex distance 2, and vertical palpebral fissure height were measured. The control group was compared to the healthy subjects of a previous study to verify any compensatory changes to the side contralateral to denervation. Results: Ten patients with unilateral Horner Syndrome were included in the study. Transitioning from photopic to scotopic conditions, the mean change in margin-to-reflex distance 1 in the study and control groups was 315 ± 276 µm (P < 0.05) and 723 ± 432 µm (P = 0.005), respectively. Margin-to-reflex distance 1 and palpebral fissure height were significantly higher in the control group both in photopic (P = 0.005 and P = 0.017, respectively) and scotopic conditions (P = 0.005 and P = 0.007, respectively). The change in margin-to-reflex distance 1 and palpebral fissure height following the transition from light to dark was significantly greater in the control group (P = 0.022). Conclusions: Reflexive eyelid retraction following a transition from photopic to scotopic conditions was significantly diminished in eyelids with sympathetic denervation compared with the unaffected contralateral side of the same patients. This study provides further evidence that the sympathetically innervated Müller's muscle serves as the efferent arm of this reflex.

Photodynamic therapy as a treatment option for peripapillary pachychoroid syndrome: a pilot study.

BACKGROUND: To investigate the anatomical and functional results in eyes with peripapillary pachychoroid syndrome (PPS) undergoing photodynamic therapy (PDT). METHODS: A total of 25 eyes from 23 patients with PPS treated with PDT were retrospectively evaluated in this multicentric study. Main outcome measure was the proportion of eyes that achieved treatment success, defined as a decrease in both subretinal fluid (SRF) height and central subfield thickness (CST), at 3 months after PDT compared to baseline. Secondary outcomes were the change in CST, SRF, and best-corrected visual acuity (BCVA) 3 months after treatment and predictive factors for treatment success. When available, data between 3 and 12 months were also reviewed. RESULTS: Treatment success was achieved in 16 eyes (64%). In the total cohort, CST decreased significantly from 356 ± 118 µm at baseline to 282 ± 90 µm and 270 ± 91 µm at 1 and 3 months, respectively (p < 0.001). Maximal SRF height decreased significantly from 102 ± 83 µm at baseline to 38 ± 46 µm and 32 ± 42 µm at 1 and 3 months, respectively (p < 0.001), and remained stable at month 6 (29 ± 44 µm) and month 12 (23 ± 35 µm). BCVA improved significantly from baseline to month 3 (p = 0.021). CONCLUSIONS: PDT can be considered an efficacious treatment option in patients with PPS. Prospective data with longer follow-up in a bigger cohort are needed in order to determine the optimal treatment algorithm in this relatively novel disease.

GRAding of functional and anatomical response to DExamethasone implant in patients with Diabetic Macular Edema: GRADE-DME Study.

To analyze functional and anatomical response patterns to dexamethasone (DEX) implant in diabetic macular edema (DME), to describe proportion of responders and non-responders, and to propose a new DME grading system. Retrospective, multicenter, observational cohort study. Naïve and non-naïve DME patients were treated with DEX, with visual acuity (VA) ≥ 0.2 logMAR and central subfield thickness (CST) of ≥ 300 µm. Functional and anatomical responses were graded after 2 and 4 months, and categorized as early and stable improvement, early and progressive improvement, pendular response, delayed improvement, and persistent non-response. 417 eyes were included (175 treatment naïve eyes). Compared to non-naïve eyes, naïve eyes showed a very good functional response (VA gain ≥ 10 letters) more frequently after 2 and 4 months (56% and 57% [naïve] vs. 33% and 28% [non-naïve], p < 0.001). A VA gain < 5 letters (non-response) after 2 and 4 months was seen in 18% and 16% of naïve eyes, and in 49% and 53% of non-naïve eyes (p < 0.001). A lack of anatomical response was rare in both groups, but more frequently in non-naïve eyes (12% vs. 4%, p = 0.003). Functionally and anatomically, naïve eyes showed most frequently an early and stable improvement (functionally: 77/175 44%; anatomically: 123/175 eyes, 70%). Most non-naïve eyes experienced no significant improvement functionally (97/242 eyes, 40%), despite a mostly early and stable improvement anatomical response pattern (102/242 eyes, 42%). Functional but not anatomical response patterns were influenced by baseline VA. Naïve and non-naïve eyes show different functional and anatomical response patterns to DEX implant. Functional non-responders are rare in naïve eyes, whereas anatomical non-response is unusual in both groups.

New insight into the physiologic function of Müller's muscle.

PURPOSE: Müller's muscle is a sympathetically innervated smooth muscle which serves as an accessory upper eyelid retractor. Its physiologic function and purpose have not yet been clearly defined. We hypothesize that sympathetic innervation to Müller's muscle serves to adjust the upper eyelid's position to variations in pupil size in response to changes in light intensity. METHODS: This is a single center cross-sectional study. Healthy volunteers were asked to fixate on a distant non-accommodative target, and a video scan of the anterior segment was performed for each subject's right eye using the Heidelberg Spectralis® optical coherence tomography scanner in infrared mode. The video was taken both in photopic and scotopic conditions, recording the resultant transition of the pupil and eyelids. The pupil diameter (PD), upper eyelid margin-to-reflex distance (MRD1), lower eyelid margin-to-reflex distance (MRD2), and vertical palpebral fissure height (PFH) were measured. RESULTS: Thirty-three healthy volunteers (19 women, 57.6%) with a median age of 40 years (range 30-58) were included. The mean PD under photopic conditions increased significantly under scotopic conditions, from 3483 ± 521 µm to 6135 ± 703 µm, respectively (P < 0.0001). An increase in MRD1 was observed following transition from light to dark, with a mean change of 348 ± 311 µm (P < 0.0001). There was no significant change in MRD2. CONCLUSIONS: Upper eyelid retraction occurs after transition from photopic to scotopic conditions. This movement suggests the existence of an "eyelid-light reflex" involving Müller's muscle that adjusts the position of the eyelids as the pupil dilates under scotopic conditions.

Demographic, clinical features, and outcomes of pediatric non-penetrating ocular foreign bodies.

PURPOSE: Data regarding ocular foreign body (FB) in the pediatric population is sparse. The purpose of this study is to describe the demographic features and the outcomes of pediatric non-penetrating ocular FB. METHODS: The charts of all children with non-penetrating ocular FB who presented at a tertiary medical center between 2011 and 2018 were retrospectively reviewed. Data analyzed included demographics, ocular FB site, the need for general anesthesia, or sedation for FB removal and clinical outcomes. RESULTS: Three hundred and fifty-two children (58.8% boys) with a mean age of 7.7 ± 3.7 years were included. Two hundred and fifty-one (71.3%) children presented on the same day of injury. Patients with developmental delay presented more often with restlessness than patients without developmental delay (p < 0.0001). One hundred and forty-six (41.5%) of FBs were found on the conjunctiva, 128 (36.4%) under the eyelid, and 62 (17.6%) on the cornea. In 19 (4.5%) cases, general anesthesia or sedation was required for FB removal. A multivariate analysis identified young age (OR 0.976, 95% CI 0.961-0.992, p = 0.003), corneal FB (OR 50.84, 95% CI 10.08-256.37, p < 0.0001), and developmental delay (OR 18.56, 95% CI 1.22-283.45, p = 0.036), as significant predictors for the need of general anesthesia or sedation. Among patients with corneal FB, in two (3.2%) cases, the corneal FB was complicated by infectious keratitis, resulting in mild corneal scar. CONCLUSION: The rate of general anesthesia for non-penetrating ocular FB removal in children is low. Children presenting with non-penetrating ocular FB have good prognosis without long-term complications.