Efficacy of teprotumumab therapy in patients with long-duration thyroid eye disease.

PURPOSE OF REVIEW: Teprotumumab, an inhibitor of the insulin-like growth factor 1 receptor (IGF-1R), was approved by the US Food and Drug Administration in January 2020 for the treatment of thyroid eye disease (TED). The clinical trials leading to its approval enrolled patients with recent disease onset and significant inflammatory symptoms and signs. Subsequent real-world teprotumumab use in patients with longer duration of disease also may be effective, and there have been several publications reporting on experience in these patient groups. RECENT FINDINGS: TED results in disfiguring changes such as ocular proptosis and affects visual function by altering extraocular muscle function, leading to diplopia. Compressive optic neuropathy also may occur, and disease manifestations may persist for years. Teprotumumab treatment in cases of TED in which prior interventions (medical or surgical) had failed, or in treatment-naïve patients whose disease had been stable for years, has been reported to improve both clinical signs and symptoms (proptosis, diplopia) and to reduce the pathologic orbital changes as assessed by orbital imaging. SUMMARY: Teprotumumab may be an appropriate treatment for TED regardless of disease duration and irrespective of the presence or absence of markers of active inflammation within the orbit.

Outcomes of Patients With Thyroid Eye Disease Partially Treated With Teprotumumab.

PURPOSE: In response to the coronavirus (COVID-19) pandemic, teprotumumab production was temporarily halted with resources diverted toward vaccine production. Many patients who initiated treatment with teprotumumab for thyroid eye disease were forced to deviate from the standard protocol. This study investigates the response of teprotumumab when patients receive fewer than the standard 8-dose regimen. METHODS: This observational cross-sectional cohort study included patients from 15 institutions with active or minimal to no clinical activity thyroid eye disease treated with the standard teprotumumab infusion protocol. Patients were included if they had completed at least 1 teprotumumab infusion and had not yet completed all 8 planned infusions. Data were collected before teprotumumab initiation, within 3 weeks of last dose before interruption, and at the visit before teprotumumab reinitiation. The primary outcome measure was reduction in proptosis more than 2 mm. Secondary outcome measures included change in clinical activity score (CAS), extraocular motility restriction, margin reflex distance-1 (MRD1), and reported adverse events. RESULTS: The study included 74 patients. Mean age was 57.8 years, and 77% were female. There were 62 active and 12 minimal to no clinical activity patients. Patients completed an average of 4.2 teprotumumab infusions before interruption. A significant mean reduction in proptosis (-2.9 mm in active and -2.8 mm in minimal to no clinical activity patients, P < 0.01) was noted and maintained during interruption. For active patients, a 3.4-point reduction in CAS ( P < 0.01) and reduction in ocular motility restriction ( P < 0.01) were maintained during interruption. CONCLUSIONS: Patients partially treated with teprotumumab achieve significant reduction in proptosis, CAS, and extraocular muscle restriction and maintain these improvements through the period of interruption.

Vision Loss Secondary to COVID-19 Associated Bilateral Cerebral Venous Sinus Thromboses.

A young, morbidly obese woman with recent SARS-CoV-2 infection requiring hospitalization presented with visual and neurologic complications secondary to bilateral cerebral venous sinus thromboses. With elevated intracranial pressure and severe papilledema, she rapidly progressed to complete bilateral vision loss despite anticoagulation, therapeutic lumbar punctures with lumbar drain, bilateral optic nerve sheath fenestrations, and endovascular thrombectomy. It is possible that obese patients with a SARS-CoV-2 infection may be at greater risk of hypercoagulable cerebrovascular complications. It is impossible to know if an even more rapid response would have led to a different outcome, but we report this case in the hope that publishing this and similar cases may result in improved treatment protocols to preserve vision.

Resolution of persistent traumatic supraorbital pain after neuroma excision.

We describe a case of an 18-year-old male who developed a supraorbital neuroma following facial trauma that occurred 2 years earlier. He presented with complaints of persistent facial pain and migraines despite successful laceration repair and removal of foreign bodies at the time of injury. A non-contrast computed tomography (CT) scan of the orbits revealed an enlarged supraorbital nerve with remodeling and expansion of the supraorbital notch, suggesting a neuroma. The patient underwent orbitotomy with excision of neuroma (confirmed histologically) and experienced a complete resolution of periorbital pain.

Vismodegib for Preservation of Visual Function in Patients with Advanced Periocular Basal Cell Carcinoma: The VISORB Trial.

BACKGROUND: Basal cell carcinoma (BCC) is a common skin cancer often curable by excision; however, for patients with BCC around the eye, excision places visual organs and function at risk. In this article, we test the hypothesis that use of the hedgehog inhibitor vismodegib will improve vision-related outcomes in patients with orbital and extensive periocular BCC (opBCC). MATERIALS AND METHODS: In this open-label, nonrandomized phase IV trial, we enrolled patients with globe- and lacrimal drainage system-threatening opBCC. To assess visual function in the context of invasive periorbital and lacrimal disease, we used a novel Visual Assessment Weighted Score (VAWS) in addition to standard ophthalmic exams. Primary endpoint was VAWS with a score of 21/50 (or greater) considered successful, signifying globe preservation. Tumor response was evaluated using RECIST v1.1. Surgical specimens were examined histologically by dermatopathologists. RESULTS: In 34 patients with opBCC, mean VAWS was 44/50 at baseline, 46/50 at 3 months, and 47/50 at 12 months or postsurgery. In total, 100% of patients maintained successful VAWS outcome at study endpoint. Compared with baseline, 3% (95% confidence interval [CI], 0.1-15.3) experienced major score decline (5+ points), 14.7% (95% CI, 5 to 31.1) experienced a minor decline (2-4 points), and 79.4% experienced a stable or improved score (95% CI, 62.1-91.3). A total of 56% (19) of patients demonstrated complete tumor regression by physical examination, and 47% (16) had complete regression by MRI/CT. A total of 79.4% (27) of patients underwent surgery, of which 67% (18) had no histologic evidence of disease, 22% (6) had residual disease with clear margins, and 11% (3) had residual disease extending to margins. CONCLUSION: Vismodegib treatment, primary or neoadjuvant, preserves globe and visual function in patients with opBCC. Clinical trail identification number.NCT02436408. IMPLICATIONS FOR PRACTICE: Use of the antihedgehog inhibitor vismodegib resulted in preservation of end-organ function, specifically with regard to preservation of the eye and lacrimal apparatus when treating extensive periocular basal cell carcinoma. Vismodegib as a neoadjuvant also maximized clinical benefit while minimizing toxic side effects. This is the first prospective clinical trial to demonstrate efficacy of neoadjuvant antihedgehog therapy for locally advanced periocular basal cell carcinoma, and the first such trial to demonstrate end-organ preservation.

Orbital inflammatory disorders: new knowledge, future challenges.

PURPOSE OF REVIEW: This review aims to bring together recent advances in basic, translational and clinical research on the pathogenesis and treatment of orbital inflammatory conditions. RECENT FINDINGS: Basic science studies provide mechanistic insights into why the orbit is targeted for inflammation by autoimmune inflammatory disorders. Using Graves' disease as a test case reveals that endocrine pathways, such as the TSH and IGF1 receptor pathways play important roles in stimulating orbital inflammation. Furthermore, orbital tissues contain high concentrations of retinoids - byproducts of the visual pathway that diffuse across the sclera and can activate de novo transcription of inflammatory cytokines. Such cytokine expression places the orbit in a hyper-inflammatory 'resting' state, prone to respond to any additional systemic or local pro-inflammatory signals. The HIF2A--LOX pathway appears important for orbital tissue fibrosis. Lastly, bench-to-bedside studies of the IGF1R pathway have led to an FDA-approved drug, teprotumumab that represents a novel treatment approach for Graves' orbitopathy. Unfortunately, high drug costs and misplaced insurance company 'step-therapy' policies may block patients from receiving therapy that can protect vision and improve quality of life. SUMMARY: Improved understanding of orbital inflammatory conditions has led to a new drug and promises additional breakthroughs. Translational research is successful, but requires time, resources, and patience.

Direct Injection of 5-Fluorouracil Improves Outcomes in Cicatrizing Conjunctival Disorders Secondary to Systemic Disease.

PURPOSE: Conjunctival cicatrizing conditions are vision threatening, with poor outcomes despite aggressive systemic therapy. This study tests the utility of serial injections of 5-fluorouracil (5-FU) into the fornices to treat conjunctival scarring in patients with ocular cicatricial pemphigoid or Stevens-Johnson syndrome/toxic epidermal necrolysis. METHODS: Retrospective cohort study. Fisher exact test and multivariable logistic regression analyses were used to compare clinical outcomes of patients who were administered 5-FU injections versus patients who were not injected. Model fit was examined for multivariable regression. RESULTS: One hundred twelve eyes (56 patients) met the inclusion criteria. Thirty-eight eyes (34%) had Stevens-Johnson syndrome/toxic epidermal necrolysis, and 74 eyes (66%) were diagnosed with ocular cicatricial pemphigoid. Twenty-five eyes received ≥1 injection of 5-FU. Sixteen eyes received 1-4 injections, while 9 received ≥5. Median follow-up until last encounter was 18 months. Analysis of each disease entity alone and in combination revealed that 5-FU injections were associated with improvement in final visual acuity, corneal scarring, trichiasis, need for/number of mucous membrane graft surgeries, and severity of symblephara. CONCLUSIONS: Serial injection of 5-FU in the affected fornices is a promising treatment for severe vision-threatening conjunctival scarring from ocular cicatricial pemphigoid and Stevens-Johnson syndrome/toxic epidermal necrolysis. Given the excellent safety profile of 5-FU around the eye, the solid biologic foundation for using 5-FU in this setting, and the severe risk of vision loss from these disorders, the authors suggest that serial 5-FU injections be adopted as therapy for conjunctival scarring from ocular cicatricial pemphigoid or Stevens-Johnson syndrome/toxic epidermal necrolysis despite the limitations of this retrospective study.

Treatment of Congenital Ptosis in Infants With Associated Amblyopia Using a Frontalis Muscle Flap Eyelid Reanimation Technique.

PURPOSE: To determine the efficacy of a frontalis muscle flap eyelid reanimation technique for correction of severe congenital ptosis and associated amblyopia in infants. METHODS: The authors performed a retrospective chart review of patients 12 months of age or younger with unilateral or bilateral congenital ptosis and associated amblyopia or deemed at high risk for amblyopia due to visual deprivation. Following ptosis repair via a frontalis muscle flap technique, primary outcomes of postoperative eyelid position and amblyopia reversal were assessed. RESULTS: Seventeen eyes of 12 participants were included for study. Seven of these patients had simple congenital ptosis, and the remainder had ptosis as part of a syndrome. Nine were diagnosed with amblyopia preoperatively, and the remaining 3 were too young for acuity testing but had occlusion of the visual axis by the ptotic eyelid in primary gaze. Postoperatively, the mean margin-to-reflex distance 1 was 2.4 mm (range: 0.0-4.0), and 9 patients (75%) demonstrated no evidence of amblyopia. Only 2 patients had eyelid asymmetry greater than 2 mm, which in both cases was due to lack of frontalis activation by the patient secondary to ongoing visual impairment. The most common complication was lagophthalmos in 6 eyes (35.3%), with no significant associated surface keratopathy. CONCLUSIONS: The frontalis muscle flap technique may offer a new and effective approach to treating infants with severe congenital ptosis causing poor eyelid excursion and associated amblyopia while avoiding use of an implant.

Reconstruction of the Orbit and Anophthalmic Socket Using the Dermis Fat Graft: A Major Review.

PURPOSE: To perform a comprehensive review of dermis fat graft (DFG) in socket reconstruction and illustrate the technical nuances and outcomes using a retrospective case review. METHODS: A literature search of 143 texts was reviewed. A retrospective case series of 34 patients following primary or secondary DFG after enucleation at a single institution (2009-2019) was performed. Clinical outcomes were statistically analyzed. Variables investigated included age, sex, race, surgical indication, muscle reattachment, complications, motility, eyelid position, prosthesis fit, and need for additional surgery. RESULTS: The history of DFG, use in socket reconstruction, primary and secondary indications, and surgical techniques are described. Thirty-two adults and 2 pediatric cases of DFG were reviewed; 18.75% indications were primary and 81.25% were secondary. Good eyelid position was observed in 83.3% of patients with primary DFG versus 37.5% with secondary DFG (p = 0.07). Postoperative complications occurred in 58.8% of patients, were typically mild, and resolved with minimal or no intervention. No statistically significant differences were found between occurrence of any particular complication in primary versus secondary DFG placement (p = 0.36) or between primary and secondary DFG placement and the need for additional surgery (p = 1.0). Among the 67.7% patients who had implant exposure or extrusion as an indication for DFG, 39.1% required additional surgery within 2 years. Advanced age was not associated with higher complication rates (p = 0.12). CONCLUSIONS: DFG is an excellent option for socket reconstruction, particularly in cases involving pediatric patients, complicated orbits, history of multiple previous surgeries, and inflamed, contracted, or scarred sockets.

Serum Vitamin D Deficiency Is an Independent Risk Factor for Thyroid Eye Disease.

PURPOSE: Thyroid eye disease (TED) is an inflammatory orbitopathy with significant impact on visual function and quality of life. Although studies have shown that patients who are deficient in vitamin D are more likely to develop autoimmune conditions, there are no studies demonstrating a definitive correlation between serum 25-hydroxyvitamin D (25(OH)D) deficiency and an increased risk of TED. METHODS: This retrospective case-control study compared serum 25(OH)D levels among 4 groups: 1) Graves disease (GD) patients with TED (n = 89); 2) GD patients without TED (n = 89); and healthy control patients matched to 3) the TED group (n = 356); and 4) the GD group (n = 356). The authors compared 25(OH)D level in the TED group measured within 1 year of TED diagnosis to the most recently measured 25(OH)D level in the GD group using Student t test of the log transformation of serum levels. Linear regression was used to control for other risk factors. Thyroid eye disease patients and GD patients were compared separately to their matched healthy control patients with linear mixed models. RESULTS: Thyroid eye disease patients displayed significantly lower serum 25(OH)D levels than GD patients (24.8 ± 13.2 ng/ml vs. 29.4 ± 13.3 ng/ml; p = 0.006). Controlling for smoking status and previous radioactive iodine treatment did not affect this statistically significant difference. CONCLUSIONS: Low serum vitamin D is associated with TED diagnosis. Assessing and supplementing vitamin D levels may be an important addition to the early management of GD patients. Future research should include longitudinal studies and prospective clinical trials to further explore the mechanism responsible for the observed association.Thyroid eye disease is an inflammatory orbitopathy associated with Graves disease. Vitamin D is a known immune system regulator. The authors show that vitamin D deficiency is associated with the development of thyroid eye disease.

Stereotactic Navigation Improves Outcomes of Orbital Decompression Surgery for Thyroid Associated Orbitopathy.

PURPOSE: To test whether intraoperative stereotactic navigation during orbital decompression surgery resulted in quantifiable surgical benefit. METHODS: This retrospective cohort study examined all consecutive patients who underwent primary orbital decompression surgery for thyroid associated orbitopathy performed by a single surgeon (A.K.) during the periods of 2012-2014 (non-navigated), and 2017-2018 (navigated). The study was HIPAA-compliant, was approved by the Institutional Review Board, and adhered to the tenets of the Helsinki declaration. Recorded parameters included patient age, sex, race, decompression technique (side of operation and walls decompressed), estimated blood loss (EBL), intraoperative complications, times that patient entered and exited the operating room (OR), times of surgical incision and dressing completion, pre- and postoperative best corrected visual acuity (BCVA), proptosis, diplopia, postoperative change in strabismus deviation, and need for subsequent strabismus surgery. Recorded times were used to calculate operating time (initial incision to dressing) and maintenance time (time between OR entry and initial incision and time between dressings and OR exit). The total maintenance time was averaged over total number of operations. Student t test was used to compare surgical times, maintenance times, EBL, and proptosis reduction. Fisher exact test was used to compare BCVA change, strabismus deviation change, resolution or onset of diplopia, and need for corrective strabismus surgery. RESULTS: Twenty-two patients underwent primary orbital decompression surgery without navigation, and 23 patients underwent navigation-guided primary orbital decompression surgery. There were no intraoperative complications in either group. The average operative time was shorter in the navigated group for a unilateral balanced decompression (n = 10 vs. 19; 125.8 ± 13.6 vs. 141.3 ± 19.4 min; p-value = 0.019), and a unilateral lateral wall only decompression (n = 13 vs. 3; 80.5 ± 12.8 vs. 93.0 ± 6.1 min; p-value = 0.041). The average maintenance time per surgery was not significantly different between the non-navigated group (51.3 ± 12.7 min) and the navigated group (50.5 ± 6.4 min). There was no significant difference between the navigated and non-navigated groups in average EBL per surgery. There was no significant difference in BCVA change. Average proptosis reduction was larger in the navigated group, but this was not significant. There was a significantly lower proportion of patients who required corrective strabismus surgery following decompression in the navigated group than in the non-navigated group (39.1% vs. 77.3%, p-value = 0.012). CONCLUSIONS: Intraoperative stereotactic navigation during orbital decompression surgery has the potential to provide the surgeon with superior spatial awareness to improve patient outcomes. This study found that use of intraoperative navigation reduced operative time (even without factoring in a resident teaching component) while also reducing the need for subsequent strabismus surgery. This study is limited by its size but illustrates that use of intraoperative navigation guidance has substantive benefits in orbital decompression surgery.

Eyelid Complications Associated with Surgery for Periocular Cutaneous Malignancies.

Periocular skin is highly prone to malignancies, especially basal cell and squamous cell carcinomas. Because of the complex anatomy and eye-protecting functions of the periocular tissues, treatment of these cancers requires special considerations. Mohs micrographic surgery is usually the treatment of choice, whenever possible, in order to enhance margin control while limiting collateral damage to nearby normal structures. Cancer excision, whether by Mohs or other techniques, will leave a complex defect that requires careful anatomical and functional reconstruction. This study presents some of the challenges of treating periocular skin cancer and associated reconstructive surgery and provides an intellectual framework for addressing these challenges. The key topics are adherence to anatomical landmarks and aesthetic units, proper distribution of tension, and matching the correct reconstructive approach, that is, type of flap or graft, to the defect at hand. This review is not meant to be exhaustive, but it will provide both basic and advanced considerations.

Surgical Management of a Recurrent Orbit-Eroding Mucocele Associated With Frontal-Ethmoidal Sinus Inverted Papilloma.

The development of orbit-eroding mucocele associated with inverted papilloma has been rarely reported., Here, the authors present a case and surgical management of a patient with orbit-eroding mucocele associated with inverted papilloma who declined craniotomy. A combined approach utilizing frontal endoscopic sinus surgery and external sub-brow anterior orbitotomy was used to explore, drain, and excise the mucocele and inverted papilloma. Gelatin sponges soaked in gentamicin were used to cover the exposed dura and to protect the orbital content from the frontal sinus cavity.A fronto-ethmoidal sinus inverted papilloma associated with recurrent orbit-eroding mucocele was excised by combined transnasal endoscopic and external sub-brow anterior orbitotomy approach using stereotactic navigation.

Absorbable Implant Foreign Body Reaction Masquerading as Orbital Cellulitis.

Poly-DL-lactide polymer implants absorb over a period of 6 to 12 months and have been used with increasing frequency for repair of orbital fractures. The authors describe the case of a 7-year-old boy who presented with orbital inflammation 10 months following repair of a white-eyed blowout fracture with a poly-DL-lactide implant. Rapid improvement in symptoms followed initiation of oral steroids, with excellent long-term result. Clinical presentation and treatment response implicated a foreign body inflammatory reaction as the underlying etiology of symptoms. Ophthalmologists and orbital surgeons should be aware that absorbable implants can demonstrate this late idiosyncratic complication.

Orbital Septum Fibrosis in Congenital Ptosis Correlates With Eyelid Function: A Clinicopathologic Study.

PURPOSE: Congenital ptosis can threaten visual function and is usually treated with surgical correction. This study tests the hypothesis that congenital ptosis involves not only the levator muscle but also the orbital septum, which may tether the eyelid in the primary position. METHODS: A retrospective chart review was performed on 30 patients (41 eyelids) with congenital ptosis who underwent surgical correction that included partial septum excision. Histologic analysis was performed by a masked pediatric pathologist, with grading of septal tissue disorganization and fibrosis based on standard histologic criteria. An independent comparison of histologic grading with clinical ptosis measures was then performed. RESULTS: Fifteen eyelids demonstrated significant septal fibrosis, 19 were mild, and 7 were not fibrotic. Thirty-six eyelids demonstrated histologic disorganization. Mildly fibrotic eyelids were found to have reduced preoperative levator function than those that were not fibrotic (2.84 ± 1.92 vs. 9.57 ± 4.76 mm; p < 0.0001). Samples that demonstrated significant fibrosis were also found to have reduced preoperative levator function (4.67 ± 2.12 vs. 9.57 ± 4.76 mm; p = 0.0007). Histologically disorganized samples were also found to have a lower preoperative levator function (9.50 ± 6.04 vs. 3.99 ± 2.49; p = 0.0052). CONCLUSIONS: Orbital septae in patients with congenital ptosis demonstrate histologic disorganization and fibrosis. When decreased levator function is observed clinically, septal fibrosis and/or disorganization is likely present. These observations suggest that debulking the fibrotic septum during congenital ptosis surgery may improve outcomes by releasing the eyelid from its congenitally tethered position, improving eyelid elasticity.

Socket Reconstruction With Bleomycin, Gentamicin, and Gelatin Sponges Following Eyelid-Sparing Orbital Exenteration for a Colobomatous Macrocyst in an Infant.

Microphthalmia is defined by a globe axial length greater than or equal to 2 standard deviations below the age-adjusted mean and can occur as part of a broader syndrome. The presence of a colobomatous cyst with microphthalmia signifies failure of the embryonic neuroectodermal fissure to close appropriately during development of the globe, creating a protuberant globular appendage that inhibits normal growth and development of the eye itself. Cystic reaccumulation of fluid is common after aspiration or surgical removal. Here, the authors describe a case of a young boy with a colobomatous cyst who underwent eyelid-sparing orbital exenteration followed by reconstruction with absorbable gelatin sponge (Gelfoam, Pfizer, Inc.) and the chemotherapeutic agent bleomycin to promote scarring, achieving the equivalent of a biointegrated implant and facilitating satisfactory placement of an ocular prosthesis. A 2-year follow-up MRI revealed adequate volume in the posterior orbit.

Retrospective Analysis of Physician-based Surveys Published in OPRS.

PURPOSE: To review physician-based clinical surveys published in Ophthalmic Plastic and Reconstructive Surgery. METHODS: Complementary Ovid and PubMed searches of Ophthalmic Plastic and Reconstructive Surgery journal content were performed for the term "survey." Results were narrowed to studies that specifically addressed physicians' clinical practices. This search resulted in 162 articles, and after dual-investigator independent screening, 13 surveys met inclusion criteria. RESULTS: Of the 13 surveys published from 2007 to January 2017, 6 were published since 2015, showing an increased trend in survey-based publications. Topics included assessing practice patterns regarding eyelid disorders, thyroid eye disease, optic nerve sheath fenestration, anophthalmic socket, and diagnosing lacrimal disorders. Average response rate was 38.7% (range 17.5-60%), with 201 average number of replies (range 72-310). Nine out of 13 surveys included some form of statistical analysis with the remainder presenting data in percentages. CONCLUSIONS: There has been an increased rate of survey-type publications in Ophthalmic Plastic and Reconstructive Surgery over the past 10 years. The low response rate and frequent lack of statistical analysis raise concerns regarding the validity and usefulness of such studies. The authors believe that survey studies can be improved through better standardization and the use of author guidelines. They have made specific recommendations to improve the impact of survey papers in the future.

Temporally distinct transcriptional regulation of myocyte dedifferentiation and Myofiber growth during muscle regeneration.

BACKGROUND: Tissue regeneration requires a series of steps, beginning with generation of the necessary cell mass, followed by cell migration into damaged area, and ending with differentiation and integration with surrounding tissues. Temporal regulation of these steps lies at the heart of the regenerative process, yet its basis is not well understood. The ability of zebrafish to dedifferentiate mature "post-mitotic" myocytes into proliferating myoblasts that in turn regenerate lost muscle tissue provides an opportunity to probe the molecular mechanisms of regeneration. RESULTS: Following subtotal excision of adult zebrafish lateral rectus muscle, dedifferentiating residual myocytes were collected at two time points prior to cell cycle reentry and compared to uninjured muscles using RNA-seq. Functional annotation (GAGE or K-means clustering followed by GO enrichment) revealed a coordinated response encompassing epigenetic regulation of transcription, RNA processing, and DNA replication and repair, along with protein degradation and translation that would rewire the cellular proteome and metabolome. Selected candidate genes were phenotypically validated in vivo by morpholino knockdown. Rapidly induced gene products, such as the Polycomb group factors Ezh2 and Suz12a, were necessary for both efficient dedifferentiation (i.e. cell reprogramming leading to cell cycle reentry) and complete anatomic regeneration. In contrast, the late activated gene fibronectin was important for efficient anatomic muscle regeneration but not for the early step of myocyte cell cycle reentry. CONCLUSIONS: Reprogramming of a "post-mitotic" myocyte into a dedifferentiated myoblast requires a complex coordinated effort that reshapes the cellular proteome and rewires metabolic pathways mediated by heritable yet nuanced epigenetic alterations and molecular switches, including transcription factors and non-coding RNAs. Our studies show that temporal regulation of gene expression is programmatically linked to distinct steps in the regeneration process, with immediate early expression driving dedifferentiation and reprogramming, and later expression facilitating anatomical regeneration.

Immediate Reconstruction After Combined Embolization and Resection of Orbital Arteriovenous Malformation.

Orbital arteriovenous malformations are rare congenital vascular anomalies that can cause eyelid distortion, proptosis, diplopia, and vision loss. The current treatment paradigm involves endovascular embolization followed by resection, with delayed reconstruction. The authors report 2 young adult patients with orbital arteriovenous malformations, who underwent embolization followed days to months later by resection with immediate soft tissue reconstruction. For both patients, the immediate outcome provided good functionality and cosmesis. The authors conclude that immediate reconstruction after embolization-resection of orbital arteriovenous malformations may facilitate early return of form and function for patients, improve quality of life, and potentially reduce the need for further reconstructive procedures.