Granulation Tissue Response Research Articles

Post-Tracheotomy Intratracheal Granulation Tissue Response to Local Injections of Triamcinolone

A 46-year-old woman came to our hospital 4 months after undergoing a tracheostomy performed at a different hospital. The endotracheal tube had been removed, and granulation tissue was present at the site of the tracheostomy. A magnetic resonance imaging scan and bronchoscopy indicated granulation tissue also present within the trachea. Two injections of triamcinolone (Kenacort-A), a synthetic adrenocortical hormone preparation, initially caused reduction in and then the disappearance of the granulation tissue, thus showing this hormone effective for its elimination. Granulation tissue formation subsequent to tracheostomy causes stenosis of the airway. The present case demonstrates an effective means for countering this problem.

Histopathological Findings in Experimental Aneurysms Embolized with Conventional and Thrombogenic/Antithrombolytic Guglielmi Coils

We studied the short- and long-term histological responses induced by conventional and modified electronically detachable coils (GDCs) in experimental aneurysms. Eighteen carotid bifurcation aneurysms were produced microsurgically in rabbits. Six animals each were treated either with conventional or with GDCs coated with a mixture of tissue-thromboplastin to enhance intra-aneurysmal thrombus formation and of plasminogen activator inhibitor type-1 (PAI-1) in inhibit intra-aneurysmal clot fibrinolysis. Six served as untreated controls. Follow-up angiograms were obtained immediately and at 3, 6, 9, 12, 17, and 24 weeks after embolization prior to sacrifice of the animals. All aneurysms were studied macroscopically and histopathologically with the coils in situ. Five of six control aneurysms remained patent. Endovascular occlusion rates between > 90% and 100% were achieved in nine of twelve coiled aneurysms. Follow-up angiography demonstrated recanalization and coil compaction in 5 of them. Gross and microscopic histopathological examination revealed a membrane covering the orifice, intra-aneurysmal scar formation, and development of a neo-intima in both treatment groups at 17 and 24 weeks postembolization. The granulation tissue response appeared to be equally distributed in aneurysms treated with either uncoated or coated coils. Further quantitative morphometric studies are needed to prove if a thrombogenic/antithrombolytic coil-coating might be of value in providing a more enduring anatomic result after GDC-treatment of human brain aneurysms.

Expression of vascular endothelial growth factor in exuberant tracheal granulation tissue in children.

Prolonged tracheotomy and endotracheal intubation often induce symptoms of airway obstruction and delay decannulation and extubation. Bronchoscopic examination of patients undergoing these treatments usually shows the presence of exuberant (pseudopapillary or nodular) granulation tissue occupying the airway lumen. An immunohistochemical analysis was undertaken of vascular endothelial growth factor (VEGF) expression in exuberant tracheal granulation tissue (n=17) obtained from children treated with prolonged tracheotomy or endotracheal intubation. Increased levels of VEGF protein and mRNA were expressed mainly by tracheal epithelial cells that migrated to cover the granulation tissue and partly by pericapillary macrophages in this tissue, whereas normal tracheal epithelium did not express VEGF. The VEGF expression level correlated significantly with the severity of the exuberant granulation tissue response (p=0.0018). As VEGF induces angiogenesis and vascular permeability, characteristics of granulation tissue, and plays a pivotal role in granulation tissue development, enhanced VEGF expression may be involved in the development of exuberant tracheal granulation tissue.

Pyogenic Granuloma of the Cornea Simulating Squamous Cell Carcinoma

A case of pyogenic granuloma involving the cornea simulated recurrent squamous cell carcinoma clinically and was misdiagnosed as invasive squamous cell carcinoma on biopsy. Ophthalmologists and pathologists should be aware of the capability of the corneal or conjunctival tissues to mount a granulation tissue response to injury.

Laryngeal injury: a critical review.

Thirty consecutive cases of laryngeal trauma requiring open exploration are reviewed. Eighteen injuries were the result of blunt trauma and 12 resulted from penetrating wounds. Within the blunt trauma group, eight of 18 injuries resulted in a competent airway and a good voice, six with a good airway but a fair voice, and four with airway compromise. Of 12 patients with penetrating wounds, ten sustained a good airway and a good voice, two a good airway and fair voice. Substantial granulation tissue response, though occurring in only eight of the 30 patients, was present in three of the four patients with airway stenosis. The use of a stent, in association with a soft tissue graft when mucosal loss cannot be approximated primarily, does not predispose to such a response, but rather facillitates maintenance of a competent skeletal framework and prevention of soft tissue endolaryngeal distortion.

Centrilobular emphysema experimentally induced by cadmium chloride aerosol.

Rats were exposed to a polydisperse aerosol of cadmium chloride solution for one hour on 5, 10, or 15 occasions. The animals developed acute vascular congestion and alveolar hemorrhage followed by polymorphonuclear cell infiltration. A granulation tissue response which tended to be localized around respiratory bronchioles subsequently occurred. By the tenth day after exposure, the granulation tissue had undergone rapid transformation to fine scar tissue with dilatation, distortion, and destruction of adjacent alveoli. The appearance of the lesions resembled human centrilobular emphysema. The severity of the emphysema as measured by the mean linear intercept method was related to the number of exposures to cadmium aerosol. Measurement of tissue cadmium confirmed accumulation of cadmium in the lungs of exposed animals; the concentration of cadmium was proportional to the number of exposures. It has been previously shown in autopsy studies that there is an increased cadmium content in the kidneys and livers ...