Nitric Oxide Synthase Inhibitor Inhibits Platelet Activating Factor: Induced Microvascular Leakage in Rat Nasal and Tracheal Mucosa / 대한이비인후과학회지

BACKGROUND AND OBJECTIVE: Platelet-activating factor (PAF), a potent chemical mediator in inflammation and allergic reaction, induces microvascular leakage in several tissues. In rat airways, PAF-induced microvascular leakage is not dependent on cyclooxygenase or lipoxygenase products nor on circulating platelets, and it is probably mediated by receptors on vascular endothelium. Nitric oxide (NO), first identified as endothelium-derived relaxing factor, has been reported recently to be an important mediator of the neurogenic vascular exudative process. The aim of this study was to investigate the role of NO in PAF-induced microvascular leakage in rat nasal and tracheal mucosa. METHODS: PAF (1 ug/kg) was injected intravenously to induce microvascular leakage. The degree of microvascular leakage was measured with the amount of extravasated Evans blue (30 mg/kg) using both spectrophotometry and fluorescence microscopy. Five Sprague-Dawley rats were pretreated with Nw-nitro-L -arginine methyl ester (L-NAME, 10 mg/kg, intravenously, 1 hour before the injection of PAF) to inhibit the NO synthase, while four control rats(n=4) were pretreated with normal saline. RESULT: The average amounts of extravasated Evans blue in the nasal mucosa and trachea of the control rats were 24.789 and 28.238 ug/mg wet tissue, and those of the L-NAME pretreated rats were 6.643 and 6.987 ug/mg wet tissue respectively. Tissue sections of the L-NAME pretreated rats showed a definitely decreased extravasation of Evans blue under fluorescence microscopy. CONCLUSION: Pretreatment with L-NAME clearly inhibited PAF-induced microvascular leakage in the nasal and tracheal mucosa of rat. This finding implies that NO may mediate PAF-induced microvascular leakage in rat airways.

Retrospective Analysis of Acute Laryngeal Trauma / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Acute laryngeal trauma is a very rare injury. Controversy still exists in regards to its proper management. The aim of this study was to present clinical findings and management of acute laryngeal trauma. MATERIALS AND METHODS:We analyzed medical records of 15 patients with acute laryngeal trauma from 1987 to 1997 retrospectively. RESULTS: The most common cause of injury was traffic accident. Hoarseness (93.3 %), odynophagia (86.7 %), subcutaneous emphysema (60.0 %) were the common presenting symptoms and thyroid cartilage was the most common site of fracture. The correlation between dyspnea (p=0.03) and subcutaneous emphysema (p=0.08) and major injury was high. Esophageal examination was performed on 11 patients and revealed no injury. All four patients with vocal cord palsy and minor injury findings improved. Patients with major injury showed bad results of airway and voice, and result of voice was worse that of airway. CONCLUSION: If presenting symptoms are emphysema and dyspnea, major injury should be considered. Routine esophageal examination may be skipped in blunt minor injury. Vocal cord palsy with minor injury finding may not be an operative indication in blunt injury.

Allergic Fungal Sinusitis: A Report of Two Cases

Allergic fungal sinusitis (AFS) is a benign, noninvasive form of fungal sinusitis. Histologically, AFS is characterized by allergic mucin, which consists of eosinophilic mucinous material with occasional laminar deposits of eosinophils. A diagnosis of AFS can be made when there is a demonstration of characteristic allergic mucin and an appearance of fungal hypae scattered within the mucin with no evidence of tissue invasion, or when fungi cultures yield positive results. Until now, no cases of AFS have been reported in Korea, though there have been many cases of mycetomas and a few cases of invasive fungal sinusitis. We present the first two cases of AFS in Korea. The patients demonstrated characteristic allergic mucin, fungal hypae scattered within the mucin, and no evidence of tissue invasion on histopathology. Nasal polyps, involvement of the unilateral sinuses, peripheral eosinophilia, an elevated total IgE, and hyperattenuated masses observed in the CT supported the diagnosis of AFS. The patients recovered and did not display recurrence after surgery and treatment with topical steroids and saline irrigation.