Ocular Irritation Testing
David W. Hobson in Dermal and Ocular Toxicology, 2020
There are several other more severe manifestations of chemical injury to the cornea, including pannus, a vascularization of the stroma. Under normal conditions, the cornea is avascular, with the exception of a few capillary loops at the edges of the stroma; however, after extensive corneal damage the stroma may become highly vascularized. The development of pannus is significant in corneal healing, and may promote re-epithelialization of the cornea by conjunctival cells. These conjunctival cells typically undergo metaplasia to corneal epithelium; however, if blood vessels are present in the cornea, the new epithelium retains its conjunctival character.28 Thus, pannus may lead to persistent or permanent visual impairment, and its presence after chemical exposure should be noted.
Valve Disease
Mary N. Sheppard in Practical Cardiovascular Pathology, 2022
The growth of host tissue on the stents is expected and is, to some extent, part of the normal healing reaction to prosthesis implantation. Pannus has both beneficial and harmful effects, in that a small amount of tissue growth over the suture line is needed for forming a nonthrombogenic surface and for the healing process to be completed. Extension of pannus onto the adjacent portions of the cusps is an exuberant reaction, which, in the longer term, can be a cause of bioprosthetic valve failure (Fig. 3.85).17 Increased pannus can extend onto the cusp surfaces and lead to thickening of the cusps, increasing its stiffness and thereby affecting its ability to open fully, ultimately resulting in stenosis and thrombosis (seeFig. 3.85) (Fig. 3.91). In addition, this pannus itself can become calcified and lead to further valve dysfunction.
Heart valve repair and replacement
Andrew R. Houghton in MAKING SENSE of Echocardiography, 2013
As far as possible, examine the structure of the mechanical valve, asking the following questions: Is the valve well seated, or does it appear to be ‘rocking’? A rocking valve prosthesis indicates a degree of separation (‘dehiscence’) of the valve’s sewing ring from the rest of the heart – look carefully for associated paravalvular regurgitation.Is there a normal range of movement of the valve occluder(s)? Occluder motion can be obstructed by thrombus or pannus (excessive fibrous or ‘scar’ tissue around the valve). Obstruction to occluder opening causes stenosis, while obstruction to occluder closure causes regurgitation.Are there any masses associated with the valve, and are the masses mobile or immobile? Pannus is an immobile mass, whereas thrombus or vegetations are usually (but not always) mobile. Pannus typically occurs 5 years or more postsurgery, although it has been found as early as 6 months post surgery. Thrombus or vegetations can occur at any time. Prosthetic valve masses usually require a TOE study for full characterization.
Ectodermal Dysplasia: Association with Anti-Basement Membrane Autoantibodies
Published in Ocular Immunology and Inflammation, 2020
Francisco Lucero Saá, Federico Andrés Cremona, Natalia Ximena Mínguez, Carina Paola Rinaudo, Pablo Chiaradía
52-year-old female with a congenital disorder associated with hair, teeth, and skin abnormalities was referred to the Ophthalmology Division at Hospital de Clinicas in Buenos Aires for diagnosis and treatment. No other family member presented a similar condition. She had a history of dry eye symptoms and severe photophobia since birth. Clinical examination showed frontal bossing, alopecia, cleft lip and palate with nasal speech, oligodontia, xerotic and hyperkeratotic skin, and severe ungueal dystrophy (Figure 1A). Ophthalmic examination revealed a visual acuity of counting fingers in each eye. Eyebrows were absent and eyelashes sparse with distichiasis. Conjunctiva of both eyes showed mild injection, subepithelial fibrosis, and fornix foreshortening. A circumferential pannus was present in both eyes. The central cornea of the left eye had an extreme thinning. Fluorescein staining showed bilateral diffuse punctate keratitis. Tear-film break-up time and Schirmer’s I test were reduced in both eyes. On the basis of clinical examination showing the triad of hypotrichosis, hypohidrosis, and oligodontia, a diagnosis of Ectodermal Dysplasia was made. As signs of cicatricial conjunctivitis were also present (Figure 1B-C), a conjunctival biopsy was performed and immunohistochemical staining techniques demonstrated linear IgG deposition along the basement membrane (Figure 1D). Treatment with systemic immunosuppression reduced the severity of photophobia and the degree of conjunctival inflammation.
Pharmacotherapeutic management of atopic keratoconjunctivitis
Published in Expert Opinion on Pharmacotherapy, 2020
Ibtesham T Hossain, Priyanka Sanghi, Bita Manzouri
Corneal involvement in atopic keratoconjunctivitis is secondary to chronic inflammation and has a spectrum of severity. Presence of inflammatory mediators, irregular lid margins, and trauma results in punctate keratitis and persistent epithelial defects. Corneal ulceration is also common and can be superimposed by infections that can be difficult to manage particularly in patients on long-term steroids [20]. Recurrent exacerbations and episodes of infection can result in pannus formation and corneal neovascularisation causing loss of vision (see Figure 3). Power et al. [21] conducted a cohort review of 20 patients and found that 70% of patients with atopic keratoconjunctivitis developed keratopathy, 60% developed corneal neovascularisation, and 50% required keratoplasty.
The INSPIRIS RESILIA Aortic Valve: From Bench to Bedside
Published in Structural Heart, 2020
Bart Meuris, Michel Aupart, Filip Rega, Quentin Langouet, Peter Verbrugghe, Thierry Bourguignon
Results: A) Preclinical sheep data: In total, 33 animals survived the whole 8-month implantation period uneventfully (6 peri-operative deaths and 4 lost due to endocarditis). The echocardiography at 8 months showed normal hemodynamic behaviour (mean gradient 4.9 ± 0.5mmHg). At autopsy, we found no major abnormalities. Histology showed no tissue failure and low pannus formation. The low calcium score on X-ray was confirmed by low calcium content values (2.4 ± 0.5 µg/mg tissue). B) Clinical data: The in-hospital mortality was 1.2% (n=3). The mean follow-up is now 12 months in this patient cohort. No major valve-related early events were observed: no early failure, thrombosis or degeneration. At discharge, we saw echo data: peak and mean gradient: 18 and 11 mmHg respectively, EOA 2.1cm2.
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