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During thermal processes utilized in affixing fluoropolymer coatings dispersion to fibers and fabrics, coating components are vaporized. It is suspected that per- and polyfluoroalkyl substances (PFAS) from the dispersions may undergo chemical transformations at the temperatures used, leading to additional emitted PFAS thermal byproducts. It is important to characterize these emissions to support evaluation of the resulting environmental and health impacts. In this study, a bench-scale system was built to simulate this industrial process via thermal application of dispersions to fiberglass utilizing relevant temperatures and residence times in sequential drying, baking, and sintering steps. Experiments were performed with two commercially available dispersions and a simple model mixture containing a single PFAS (6:2 fluorotelomer alcohol [6:2 FTOH]). Vapor-phase emissions were sampled and characterized by several off-line and real-time mass spectrometry techniques for targeted and nontargeted PFAS. Results indicate that multiple PFAS thermal transformation products and multiple nonhalogenated organic species were emitted from the exit of the high temperature third (sintering) furnace when 6:2 FTOH was the only PFAS present in the aqueous mixture. This finding supports the hypothesis that temperatures typical of these industrial furnaces may also induce chemical transformations within the fluorinated air emissions. Experiments using the two commercial fluoropolymer dispersions indicate air emissions of part-per-million by volume (ppmv) concentrations of heptafluoropropyl-1,2,2,2-tetrafluoroethyl ether (Fluoroether E1), as well as other PFAS at operationally relevant temperatures. We suspect that E1 is a direct thermal decomposition product (via decarboxylation) of 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy)propanoic acid (commonly referred to as HFPO-DA) present in the dispersions. Other thermal decomposition products, including the monomer, tetrafluoroethene, may originate from the PFAS used to stabilize the dispersion or from the polymer particles in suspension. This study represents the first researcher-built coating application simulator to report nontargeted PFAS emission characterization, real-time analyses, and the quantification of 30 volatile target PFAS. Implications: Thermal processes used to affix fluoropolymers to fabrics are believed to be a source of PFAS air emissions. These coating operations are used by many large and small manufacturers and typically do not currently require any air emissions control. This research designed and constructed a bench-scale system that simulates these processes and used several off-line and advanced real-time mass spectroscopy techniques to characterize PFAS air emissions from two commercial fluoropolymer dispersions. Further, as the compositions of commercial dispersions are largely unknown, a model three-component solution containing a single PFAS was used to characterize emissions of multiple PFAS thermal transformation products at operationally relevant conditions. This research shows that fluoropolymer fabric coating facilities can be sources of complex mixtures of PFAS air emissions that include volatile and semivolatile PFAS present in the dispersions, as well as PFAS byproducts formed by the thermal transformation of fluorocarbon and hydrocarbon species present in these dispersions. [ABSTRACT FROM AUTHOR]

While a rare ophthalmic pathogen, infections from Exophilia spp. are increasingly identified and have been associated with catastrophic vision loss. In this case report we present a previously undescribed manifestation of the melanin-producing fungus Exophilia Phaeomuriformis to the lower eyelid, establish an effective treatment, and review related cases. Previous cases of ophthalmic E. Phaeomuriformis were confined to the cornea and included iatrogenic tissue trauma. This case shares neither associations however includes a remote SJS history that likely led to changes in conjunctival tissue integrity. Previous cases of Exophilia spp. infecting the eyelid both included surgical source control and adjuvant antibiotic. In this case, topical therapy was deferred due to SJSrelated ocular cicatricial disease. Fortunately, a full resolution was achieved with surgical resection and oral antifungal treatment. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental pollutants associated with negative health impacts. Assessments of tubing-related measurement bias for volatile PFAS are lacking, as gas-wall interactions with tubing can delay quantification of gas-phase analytes. We use online iodide chemical ionization mass spectrometry measurements to characterize tubing delays for three gas-phase oxygenated PFAS − 4:2 fluorotelomer alcohol (4:2 FTOH), perfluorobutanoic acid (PFBA), and hexafluoropropylene oxide dimer acid (HFPO-DA). Perfluoroalkoxy alkane and high-density polyethylene tubing yielded relatively short absorptive measurement delays, with no clear dependence on tubing temperature or sampled humidity. Sampling through stainless steel tubing led to prolonged measurement delays due to reversible adsorption of PFAS to the tubing surface, with strong dependence on tubing temperature and sample humidification. Silcosteel tubing afforded shorter measurement delays than stainless steel due to diminished surface adsorption of PFAS. Characterizing and mitigating these tubing delays is crucial for reliable quantification of airborne PFAS. Implications: Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants. Many PFAS are sufficiently volatile to exist as airborne pollutants. Measurements and quantification of airborne PFAS can be biased from material-dependent gas-wall interactions with sampling inlet tubing. Thus, characterizing these gas-wall interactions are crucial for reliably investigating emissions, environmental transport, and fates of airborne PFAS. [ABSTRACT FROM AUTHOR]

To investigate the role of nonsurgical management in the treatment of orbital cellulitis complicated by subperiosteal abscess (SPA) in adolescent and adult populations. A retrospective cohort study to assess the demographic, clinical, and outcome profiles of adolescent and adult patients with orbital SPA treated nonsurgically versus those who received surgical intervention. Primary outcome measures included hospitalization length and best-corrected visual acuity (BCVA) in the final evaluation. The study comprised 76 patients diagnosed with SPA in the setting of orbital cellulitis. Twelve were stratified into the nonsurgical cohort, while 64 represented the surgical group. Sinusitis was the most prevalent risk factor among both populations, and the rate did not differ significantly. SPA was located medially at a significantly higher rate in the nonsurgical cohort compared with the surgical. No patients in the nonsurgical population had a relative afferent pupillary defect (RAPD) on presentation. The proportion of patients who received adjunctive systemic corticosteroid therapy was comparable in both groups. Hospitalization length was significantly higher in the surgery cohort. BCVA in the final evaluation was favourable in both groups. Sinusitis subgroup analysis including eight nonsurgical patients produced overall consistent results. Findings from the largest study of orbital cellulitis complicated by SPA to date demonstrate a role for nonsurgical management in adolescent and adult patients who present with a medial SPA and/or ophthalmic examination without an RAPD. Among these populations, visual prognosis is favourable whether management includes surgical debridement or not, and surgical intervention may not predict a shorter duration of hospitalization. [ABSTRACT FROM AUTHOR]

Sphenoid sinus mucoceles (SSMs) are rare, benign lesions that can expand, often presenting with ocular symptoms—decreased vision, diplopia, visual field defects, proptosis, and external ophthalmoplegia. Reported cases are few, visual compromise varies, and factors affecting visual prognosis are poorly characterized. We investigate whether prompt surgical intervention (within 2 weeks of visual symptom onset) affects best-corrected visual acuity (BCVA) regained in patients with vision loss secondary to compressive SSM. We present a retrospective review of three cases and published literature to date. Our primary outcome was BCVA regained after surgical intervention; secondary outcomes included change in visual field defect and ophthalmological symptoms other than vision loss. Our three cases of SSM varied in onset, ranging from several hours to several months with patients aged from 13 to 80 years. All patients had severe vision loss to light perception (LP) or worse. Rapid neuro-imaging and urgent surgical intervention improved vision to count fingers at best. Of the two patients who underwent prompt decompression, one improved from no LP to LP and the other did not recover any vision. The patient who had visual loss for 3 months before intervention improved from LP to 20/400. Findings from our literature search, which yielded 12 cases of urgent intervention, supported the variability in visual prognosis despite prompt surgical intervention. SSMs are rare, pathologically benign lesions which can expand to cause ocular involvement. Prompt diagnosis and surgical decompression are recommended, but visual recovery may be limited even with urgent intervention. [ABSTRACT FROM AUTHOR]

PurposeMethodsResultsConclusionsThe aim of this study was to assess predictors and outcomes of subperiosteal abscess (SPA) management in adolescents and adults at two tertiary care centers.This retrospective cohort study included cases of SPA from January 1 2000 to October 9 2022 at two institutions. Patients 9 years or older were categorized into surgical and nonsurgical cohorts. Surgical subgroups included those who underwent functional endoscopic sinus surgery (FESS) alone, external (transcutaneous or transconjunctival) orbitotomy alone, or combined FESS and external surgery. The presented features were assessed as potential treatment predictors. Outcomes included length of stay (LOS), final best-corrected visual acuity (BCVA), readmission rate, and reoperation rate.Of the 159 SPA cases included, 127 (79.9%) underwent surgery and 32 (20.1%) were managed nonsurgically. The nonsurgical cohort was younger (p = .003) with smaller abscesses (p < .001) that were more likely to be medial (p < .001). The nonsurgical cohort had shorter LOS (p < .001); final BCVA and readmission rates were similarly favorable. Abscess location was correlated with surgical approach. Superior SPA that underwent FESS or external surgery alone had higher reoperation rates (57.1.0% and 58.3%, respectively) than combined (17.9%). External approach and FESS alone resulted in lower reoperation rates (15.4% and 15.0%, respectively) than combined (27.3%) for medial SPA. Subgroup analysis in the sinusitis cohort yielded similar results.A trial of nonsurgical management may be safe and effective for select patients aged 9 years and older with sinusitis-derived, medial, and small SPA. When surgery is indicated, approach should be guided by abscess location to minimize reoperation risk. [ABSTRACT FROM AUTHOR]