Eosinophilic angiocentric fibrosis and immunoglobulin 4-related disease revisited.

Eosinophilic angiocentric fibrosis (EAF) has been postulated to lie on the spectrum of IgG4-related disease (IgG4-RD) in a study reported in 2011. However, the aetiology of EAF remains controversial, despite increasing literature reporting IgG4-RD targeted investigations in those studies. This review aims to formally evaluate the relationship between EAF and IgG4-RD using the latest 2019 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) classification scheme for IgG4-RD. A literature search was performed on the PubMed database for all studies describing patients diagnosed with EAF. Additionally, two EAF cases were retrospectively identified from our institution and presented. The demographics, clinical presentation, histological and serological data of each patient were analysed. A total of 20 cases were evaluated, including 18 patients from 14 articles in the English literature and two cases from our institution. Six of 20 (30%) patients with EAF met the criteria for IgG4-RD with the 2019 ACR/EULAR classification scheme. This represents the first attempt at formally evaluating the relationship between EAF and IgG4-RD using a validated set of classification criteria. Using the currently available data, a small proportion of patients with EAF met the criteria for IgG4-RD. However, various limitations of this study suggest that further efforts at disease characterization of EAF may be required.

Gaze-evoked deformations of the optic nerve head in thyroid eye disease.

PURPOSE: To assess gaze evoked deformations of the optic nerve head (ONH) in thyroid eye disease (TED), using computational modelling and optical coherence tomography (OCT). METHODS: Multiple finite element models were constructed: one model of a healthy eye, and two models mimicking effects of TED; one with proptosis and another with extraocular tissue stiffening. Two additional hypothetical models had extraocular tissue softening or no extraocular tissue at all. Horizontal eye movements were simulated in these models. OCT images of the ONH of 10 healthy volunteers and 1 patient with TED were taken in primary gaze. Additional images were recorded in the same subjects performing eye movements in adduction and abduction. The resulting ONH deformation in the models and human subjects was measured by recording the 'tilt angle' (relative antero-posterior deformation of the Bruch's membrane opening). RESULTS: In our computational models the eyes with proptosis and stiffer extraocular tissue had greater gaze-evoked deformations than the healthy eye model, while the models with softer or no extraocular tissue had lesser deformations, in both adduction and abduction. In healthy subjects, the mean tilt angle was 1.46°±0.25 in adduction and -0.42°±0.12 in abduction. The tilt angle measured in the subject with TED was 5.37° in adduction and -2.21° in abduction. CONCLUSION: Computational modelling and experimental observation suggest that TED can cause increased gaze-evoked deformations of the ONH.

Cosmetic and functional outcomes of frontalis suspension surgery using autologous fascia lata or silicone rods in pediatric congenital ptosis.

PURPOSE: Cosmetic and functional outcomes of frontalis suspension surgery using autologous fascia lata (FL) or silicone rods (SRs) in pediatric congenital ptosis. DESIGN: Retrospective case series. STUDY SUBJECTS: Patients with congenital ptosis, aged 18 years or younger, during the period under study (2005-2011) at the Singapore National Eye Centre. METHODS: Review of case records for functional and cosmetic outcome measures after frontalis suspension surgery using either SRs or autologous FL. RESULTS: A total of 18 patients were studied (14 eyelids had FL, 16 eyelids had SRs) with mean ages of 7.1 (range 5-12) and 7.2 (range 4-18) years for the FL and SR groups, respectively. Mean follow-up period was 41.6 (range 11.2-77.9) and 48.6 (16.1-87.4) months, respectively. Patients in the FL group had better functional and cosmetic results compared to those in silicone group, with no recurrence of ptosis. More complications were experienced by patients in the SR group. CONCLUSION: Autologous FL for frontalis suspension remains an excellent choice for (and should be considered as useful surgical armamentarium for) repair of severe congenital ptosis.

Fibrin glue for Gundersen flap surgery.

PURPOSE: To evaluate the feasibility of fibrin glue in Gundersen flap surgery. DESIGN: Prospective case series. STUDY SUBJECTS: Seven eyes of seven subjects who had undergone Gundersen flap surgery from 2009 to 2011 at the Singapore National Eye Centre, Singapore. METHODS: Review of case records for outcomes after Gundersen flap surgery. MAIN OUTCOME MEASURES: Surgical success was defined as achieving a stable ocular surface. Complications to be noted included flap retraction or exposure of underlying corneal surface. RESULTS: Surgical success was achieved in all eyes with significant reduction in ocular surface inflammation. No retractions were noted and recovery was uncomplicated. CONCLUSION: Fibrin glue application is a viable alternative to sutures in Gundersen flap surgery. It reduces surgical downtime, gives faster ocular surface rehabilitation, and offers similar outcomes to conventional conjunctival flap surgery.

Porous tantalum and poly-epsilon-caprolactone biocomposites for osteochondral defect repair: preliminary studies in rabbits.

Currently, various techniques are in use for the repair of osteochondral defects, none of them being truly satisfactory and they are often two step procedures. Comorbidity due to cancellous bone harvest from the iliac crest further complicates the procedure. Our previous in vitro studies suggest that porous tantalum (TM) or poly-epsilon-caprolactone scaffolds (PCL) in combination with periosteal grafts could be used for osteochondral defect repair. In this in vivo study, cylindrical osteochondral defects were created on the medial and lateral condyles of 10 rabbits and filled with TM/periosteum or PCL/periosteum biosynthetic composites (n = 8 each). The regenerated osteochondral tissue was then analyzed histologically, and evaluated in an independent and blinded manner by five different observers using a 30-point histological score. The overall histological score for PCL/periosteum was significantly better than for TM/periosteum. However, most of the regenerates were well integrated with the surrounding bone (PCL/periosteum, n = 6.4; TM/periosteum, n = 7) along with partial restoration of the tidemark (PCL/periosteum, n = 4.4; TM/periosteum, n = 5.6). A cover of hyaline-like morphology was found after PCL/periosteum treatment (n = 4.8), yet the cartilage yields were inconsistent. In conclusion, the applied TM and PCL scaffolds promoted excellent subchondral bone regeneration. Neo-cartilage formation from periosteum supported by a scaffold was inconsistent. This is the first study to show in vivo results of both PCL and TM scaffolds for a novel approach to osteochondral defect repair.

Cell-laden and cell-free biopolymer hydrogel for the treatment of osteochondral defects in a sheep model.

The objective of the current study was to determine the suitability of cell-laden and cell-free alginate-gelatin biopolymer hydrogel for osteochondral restoration in a sheep model (n = 12). Four femoral defects per animal were filled with hydrogel (cHG) plus autologous chondrocytes (cHG + C) or periosteal cells (cHG + P) or gel only (cHG) or were left untreated (E). In situ solidification enabled instantaneous implant fixation. Sixteen weeks postoperatively, defect sites were processed for light microscopy and immunofluorescence. A modified Mankin and a semi-quantitative immunoreactivity score were used to evaluate histology and immunofluorescence, respectively. Defects after cHG + C were restored with smooth, hyaline-like neo-cartilage and trabecular subchondral bone. cHG + P and cHG treatments revealed slightly inferior regenerate morphology. Undifferentiated tissue was found in E. The histological score showed significant (p < 0.05) differences between all treatment groups. In conclusion, cHG induces satisfactory defect regeneration. Complete filling of the cavity in one step and subsequent rapid in situ solidification was feasible and facilitated graft fixation. Cell implantation might be beneficial, because cells seem to play a key role in histological outcome. Still, their contribution to the repair process remains unresolved because host cell influx takes place. The combination of alginate and gelatin, however, creates an environment capable of serving implanted and host cells for osteo-chondrogenic tissue regeneration.