Impact of Allergic Rhinitis on Voice in Children.

INTRODUCTION: The purpose of the present study was to determine the possible effect of allergic rhinitis (AR) on voice change in children with acoustic analysis and Turkish children's voice handicap index-10 (TR-CVHI-10). METHODS: This is a case-control study. Forty-one children with AR, and a positive skin prick test, as well as 39 children of controls who had produced a negative skin prick test and lacked a history of allergic disease, were selected for the study. Each assessment included recordings for the purposes of acoustic voice analysis (fundamental frequency [f0], jitter %, shimmer %, and harmonics-to-noise ratio (HNR)), and aerodynamic analysis (maximum phonation time (MPT) and s/z ratio). All participants completed TR-CVHI-10. RESULTS: The mean TR-CVHI-10 score of the AR group was significantly higher than the control group (p = 0.013). No difference was observed between the AR and control groups in terms of jitter, shimmer, HNR, and MPT values and s/z ratio (p > 0.05). Conversely, the f0 value was more pronounced in controls (270.9 ± 60.3 Hz) than in the AR group (237.7 ± 54.3 Hz) (p = 0.012). CONCLUSION: The study's results revealed that AR can have an effect on fundamental frequency and voice quality in children. The diagnostic process should include AR as a potential cause of voice disorders in children.

Platelet-rich plasma for laryngotracheal reconstruction: an experimental study.

OBJECTIVES/HYPOTHESIS: This study was designed to evaluate the graft healing effect of topical application of platelet-rich plasma (PRP) for laryngotracheal reconstruction (LTR) in a rabbit model. STUDY DESIGN: It is a prospective randomized control animal study. MATERIALS AND METHODS: Sixteen healthy New Zealand White rabbits were assigned to two groups of eight animals each. The control group underwent LTR with anterior auricular cartilage graft. The PRP group underwent the same surgical procedure plus PRP application over the anastomosis and surgical field. Two animals in the PRP group and two animals in control group died due to severe respiratory distress on postoperative days 10, 12, 15, and 18. Six rabbits (n = 3 for control group and n = 3 for PRP group) were sacrificed at 4 weeks, and six rabbits (n = 3 for control group and n = 3 for PRP group) were sacrificed at 8 weeks. Laryngotracheal regions were evaluated histopathologically. RESULTS: Macroscopically, the average anteroposterior and lateral diameter of the reconstructed region and the degree of lumen patency on postoperative 4th week and 8th week were not statistically different among two groups. There was no significant difference between the groups in terms of any of the microscopic findings when the analysis was made separately. However, analysis of the total number of rabbits has shown that new cartilage formation and angiogenesis were more pronounced in PRP group than control group. CONCLUSIONS: Application of PRP contributed to better healing in airway surgery by promoting a release of growth factors that stimulate new cartilage formation and angiogenesis.

Decreased ovarian reserve in female Sprague-Dawley rats induced by isotretinoin (retinoic acid) exposure.

Isotretinoin is a retinoid widely used for the treatment of severe nodulocystic acne. Although it has broad side effects, there is no well-designed study about its effects on the ovary. This study investigated possible toxic effects of isotretinoin on female gonads. A total of 30 female rats were randomly divided into three equal groups according to the dose of isotretinoin they were administered: 0 mg/kg/day (group 1), 7.5 mg/kg/day (group 2) or 15 mg/kg/day (group 3). Thirty days after the treatment, the effects of isotretinoin on the ovaries were evaluated with serum anti-Müllerian hormone (AMH) concentrations, apoptosis by TUNEL assay and immunohistochemical observations by proliferating cell nuclear antigen (PCNA). The percentage of atretic follicles was calculated for each stage of folliculogenesis. The serum AMH concentrations were found to be lower in both isotretinoin groups. The percentage of atretic follicles in both isotretinoin groups was higher than the control. The number of PCNA-positive granulosa cells was decreased in the isotretinoin groups. The number of ovarian follicles with apoptotic granulosa cells was increased in the experimental groups. These data are the first to identify that exposure of isotretinoin may be responsible for decreased ovarian reserve and toxic effects on rat ovaries.

Plasma fibrinogen-like protein 2 levels in patients with non-alcoholic fatty liver disease.

BACKGROUND/AIMS: Fibrinogen-like protein 2 (fgl2), has recently been identified as a new member of the fibrinogen-like family of proteins. In this study we assayed plasma levels of fgl2 in patients with biopsy proven non-alcoholic fatty liver disease (NAFLD) and examined their association with clinical, biochemical and histological phenotypes. METHODOLOGY: Levels of plasma fgl2 were measured by enzyme linked immunosorbent assay and compared between the study groups. Moreover, concentrations of fgl2 were assessed in relation to the general characteristics of the study participants and the results of the liver biopsy. RESULTS: Levels of fgl2 were significantly higher in patients with definite non-alcoholic steatohepatitis (NASH) (788±190pg/mL, p<0.001) and borderline NASH (710 ± 140pg/mL, p<0.001) compared with controls (515±174pg/mL). No significant differences were found in patients with simple steatosis (649 ± 162pg/mL) as compared with controls. There were no associations between the plasma fgl2 levels with the fibrosis stage and steatosis grade. CONCLUSIONS: Although subject to future confirmation, our data suggest that fgl2 levels are elevated in the more severe forms of NAFLD.

The role of carnitine in preventing renal damage developed as a result of infrarenal aortic ischemia-reperfusion.

BACKGROUND: This study was designed to use carnitine for preventing deposition of end products of lipid peroxidation in rat models in the prevention of ischemia-reperfusion (IR) damage frequently seen following operations of infrarenal abdominal aorta (AA). METHODS: Forty male rats of Sprague-Dawley type were evenly (n = 8) randomized to five groups: sham laparotomy (SHAM), carnitine control (CC), aortic IR (AIR), AIR + low-dose carnitine (AIR+LDC), and AIR + high-dose carnitine (AIR+HDC). RESULTS: Compared to other groups, serum creatinine levels of AIR group were significantly higher. Also tissue malondialdehyde (MDA) levels of AIR group were significantly higher compared to SHAM, CC, and AIR+HDC groups. In histopathological examination, although tubular necrosis atrophy and tubular degeneration observed in AIR group showed regression with low-dose carnitine, tubular necrosis atrophy, tubular degeneration, glomerular damage, and vascular congestion thrombosis decreased with high-dose carnitine. Total score of histological damage was significantly higher in AIR, AIR+LDC, and AIR+HDC groups compared to SHAM and CC groups. Moreover, total score of histological damage was significantly lower in AIR+HDC group than AIR+LDC group. CONCLUSIONS: In this study, we showed carnitine can partially prevent renal damage in infrarenal AIR models of rats. This result may open new prospects to us in the prevention of renal IR damage during surgery of aorta.

The protective effect of avocado soybean unsaponifilables on brain ischemia/reperfusion injury in rat prefrontal cortex.

OBJECT: We investigated the protective effects of avocado/soybean unsaponifiables (ASU) on the prefrontal cortex (PFC) after global brain ischemia/reperfusion (I/R) injury in rats. METHODS: Rats were randomly divided into three experimental groups as follows: Group I was control rats, Group II was ischemia rats, Group III was Isch + ASU rats. Brain ischemia was produced via four-vessel occlusion model. These processes followed by reperfusion for 30 min for both II and III groups. Rats were sacrificed and their brains were removed immediately. Malondialdehyde (MDA) and superoxide dismutase (SOD) were measured in left PFC, levels of TNF-α concentration were measured in the plasma. The number of apoptotic neurons was assayed in histological samples of the right PFC. RESULTS: MDA and TNF-α levels as well as the number of apoptotic neurons were observed to have decreased significantly in Group III compared to Group II, while SOD activities have been found to have increased significantly in Group III in comparison to Group II, significantly. CONCLUSIONS: We think that ASU might have an antioxidant and neuroprotective effects in brain I/R injured rats.

A Patient with Severe Cervicofacial Subcutaneous Emphysema Associated with Munchausen's Syndrome: A Case Report.

Subcutaneous cervicofacial emphysema is a rare and life-threatening condition that results from various causes. In this report, we documented a case of a patient with severe subcutaneous cervicofacial emphysema a condition that falls under the umbrella of Munchausen's syndrome and discussed the workup of this patient. Thorough diagnostic investigations seeking the etiology of the condition proved unsuccessful. When faced with cases of recurring subcutaneous cervicofacial emphysema, where the root cause remains ambiguous a diagnosis of Munchausen's Syndrome should be considered.

Metastatic basal cell carcinoma presenting as a neck mass.

Neck masses are common in physicians' daily practice; however, there is a small possibility that the origin of the neck mass is a basal cell carcinoma (BCC). We present a BCC of the scalp that metastasizes to the neck without any lymphoid involvement. We also reviewed possible risk factors for metastasis of the BCC, which is a probable cause of neck mass.

Congenital midnasal stenosis: Conservative management.

INTRODUCTION: Congenital midnasal stenosis (MNS) is an extremely rare disease which may be life threatening, and shows difficulty in diagnosis and management. This case series summarizes superiority of using intranasal mometasone furoate spray (IMS) and continuous positive airway pressure (CPAP) to treat nasal obstruction in neonates with MNS. METHODS: This study reviewed six consecutive cases of MNS. RESULTS: Three patients were treated with IMS and CPAP. Two patients were treated with endoscopic balloon dilatation without stenting, followed by IMS and CPAP due to persisting nasal obstruction after the operation. One patient was treated with endoscopic balloon dilatation without stenting alone. CONCLUSION: This study is the first to review the use of CPAP and IMS as an effective therapy for some patients with MNS. It suggests that conservative management with CPAP and IMS may be an alternative therapeutic option to surgery.

Expression of cyclooxygenase-2 and matrix metalloproteinase-2 in adenomyosis and endometrial polyps and its correlation with angiogenesis.

This study investigates the expression of cyclooxgenase (COX)-2 and matrix metalloproteinase (MMP)-2 in patients with adenomyosis or endometrial polyps and their possible relation to microvascular density in these lesions. The subjects were 25 patients with adenomyosis, 30 patients with endometrial polyps, and 20 female controls. The expression of COX-2, MMP-2, and CD34 was studied immunohistochemically. Microvesseldensity (MVD) was calculated by the counting of CD34-positive vascular endothelial cells. The quantity and intensity of COX-2 expression in endometrium did not vary during the menstrual cycle in the control group and in patients with endometrial polyps. In patients with adenomyosis, it was higher in the secretory phase. MMP-2 expression in stromal cells in adenomyotic foci and endometrial polyps were higher than in normal endometrium. In the proliferative phase, MVD in adenomyosis foci was higher than in normal endometrium and endometrial polyps. In the secretory phase, MVD in adenomyotic foci and endometrial polyps was higher than in normal endometrium. Overexpression of stromal MMP-2 may play a role in the development of adenomyosis and endometrial polyps. Aberrant COX-2 expression in eutopic endometrium during the luteal phase may be associated with the pathogenesis of adenomyosis; however, expression of COX-2 does not seem to play a role in the development of endometrial polyps. MVD was high in both lesions, but there was no significant correlation between MVD and the expression of MMP-2 or COX-2. Mechanisms other than COX-2 and MMP-2 may contribute to the promotion of angiogenesis in these lesions.

The neuroprotective effect of dexmedetomidine in the hippocampus of rabbits after subarachnoid hemorrhage.

BACKGROUND: Subarachnoid hemorrhage is a serious condition, often accompanied by cerebral vasospasm, which may lead to brain ischemia and neurologic deterioration. We evaluated if dexmedetomidine has neuroprotective effects in the hippocampus of vasospastic SAH rabbits or not. MATERIALS AND METHODS: Eighteen New Zealand rabbits were taken. An experimental SAH model was formed by injecting 0.9 mL of autologous arterial blood per 1 kg of body weight to the cisterna magna of 12 rabbits. Craniotomy was performed in the control group (n = 6) except performing experimental SAH. Rabbits in the SAH-alone (n = 6) group were infused with 5 mL.kg(-1).h(-1) 0.9% sodium chloride, and rabbits (n = 6) in the SAH-dexmedetomidine group were infused with 5 microg.kg(-1).h(-1) dexmedetomidine for 2 hours, 48 hours after SAH was established. Rabbits of all groups were sacrificed via penthotal 24 hours after dexmedetomidine administration. Brains were removed immediately, and hippocampal tissues were blocked from the right hemisphere for histopathologic study. In addition to this, hippocampal tissues of left hemispheres were dissected for biochemical analyses to evaluate MDA levels, activity of XO, and SOD. RESULTS: The histopathologic study showed that dexmedetomidine may have a neuroprotective effect in SAH-induced hippocampal injuries. The biochemical parameters support the neuroprotective effect of dexmedetomidine (P < .05). CONCLUSION: Our study showed that dexmedetomidine may have a neuroprotective effect in the hippocampus of vasospastic SAH rabbits.

Pilomatricoma: a review of six pediatric cases with nine lesions.

Pilomatricoma, although rare, is the second most frequent benign skin tumor in childhood. It is a hard, painless, slowly progressing subcutaneous tumor that is commonly located in the head-neck region, especially periorbital, and in the upper extremities. Histopathologic characteristics are distinctive. In this study, we performed a retrospective review of the records of our pediatric patients with pilomatricoma. We discuss herein the diagnosis and management of this uncommon skin tumor, and compare our experience with the previous literature. Pilomatricoma should be included in the differential diagnosis of superficial pediatric head and neck masses by any physician involved with pediatric tumors.

A rare structural myopathy: Nemaline myopathy.

Nemaline myopathy, which is characterized by the accumulation of ''rod'' bodies in muscle fibers is a very rare inherited muscle disease. According to the underlying mutation, the disease has varying severity of clinical outcomes. Patients with severe forms of the disease die because of hypotonia, feeding difficulties, aspiration pneumonia, and respiratory failure in the neonatal or infancy period. Mild forms of the disease present with walking-swallowing difficulties and respiratory distress in late childhood or adulthood. A two-and-a-half-month-old boy was monitored in our Pediatric Intensive Care Unit with hypotonia, pneumonia, and respiratory distress. Nemaline myopathy was diagnosed as the result of a muscle biopsy. An advanced molecular examination revealed heterozygous mutations in the skeletal muscle α-actin (ACTA1) gene, which is the second most common cause of this disease. Nemaline myopathy should be kept in mind in patients of all age groups with respiratory failure and walking difficulty secondary to muscle weakness.

Nemalin miyopatisi oldukça nadir görülen kalitimsal bir kas hastaligi olup kas liflerinde ''rod''(nemalin) cisimcigi birikimi ile tanimlanmaktadir. Hastalik altta yatan mutasyona ve mutasyonun kalitim biçimine göre degisen agirlikta klinik gidise sahiptir. Agir sekillerinde olgular yutma ve solunum kaslarinin etkilenmesi sonucu beslenme yetersizligi, aspirasyon pnömonisi ve solunum yetmezligi nedeni ile yenidogan ya da süt çocuklugu döneminde kaybedilmektedir. Geç baslangiçli hafif olgular yasam kalitesini bozan yürüme-yutma zorlugu ve solunum sikintisi ile geç çocukluk ya da eriskin yasta bulgu verebilmektedir. Hipotoni, pnömoni ve solunum sikintisi ile Çocuk Yogun Bakim Birimi'nde izlenen iki buçuk aylik erkek bebege kas biyopsisi sonucu nemalin miyopatisi tanisi koyuldu. Ileri moleküler inceleme sonucu hastaligin ikinci en sik nedeni olan "Skeletal Muscle α-Actin" (ACTA1) geninde heterozigot mutasyon saptandi. Yenidogan döneminden eriskin döneme kadar kas güçsüzlügüne bagli solunum yetmezligi ve yutma-yürüme güçlügü varliginda yapisal miyopatiler içinde nemalin miyopatisi akilda bulundurulmali, süphenilen olgulara kas biyopsisi ya/ya da genetik inceleme yapilmalidir.

Predictive fiberoptic endoscopic findings of upper airway in children with allergic rhinitis.

OBJECTIVE: To determine predictive fiberoptic findings of upper airway in children with allergic rhinitis. METHOD: 129 children had fiberoptic evaluation of nasal cavity, pharynx and larynx. They were divided into allergic rhinitis group and normal group based on skin prick test results. All video recordings were randomly reviewed by three independent national board-certified otolaryngologists who were blinded to the clinical details and outcomes of the participants' allergy testing. Each physician assessed and documented 10-item questionnaire. Intra-rater, inter-rater reliability and correlation between items and allergic status was calculated. RESULTS: Intra-rater reliability was moderate to perfect for all physicians on all items (kappa = 0.578-0.962). Inferior turbinate hypertrophy (κ = 0.714, p = 0.02), middle turbinate hypertrophy (κ = 0.728, p = 0.01), discoloration of inferior turbinate (κ = 0.685, p = 0.01), adenoid hypertrophy (κ = 0.662, p = 0.02) had good inter-rater reliability and these findings were predictive of allergic rhinitis. Adenoid hypertrophy was less encountered in allergic rhinitis. All other endoscopic findings beyond the nasal cavity were not predictive for allergic rhinitis in children. CONCLUSION: Nasal cavity findings including inferior turbinate hypertrophy, middle turbinate hypertrophy, discoloration of inferior turbinate and adenoid tissue assessment rather than pharyngolaryngeal findings are predictive of allergic rhinitis in children.

The influence of dexmedetomidine on ischemic rat hippocampus.

In our study, we evaluated the neuroprotective effects of dexmedetomidine on oxidant-antioxidant systems, pro-inflammatory cytokine TNF-alpha and number of apoptotic neurons on hippocampus and dentate gyrus after transient global cerebral I/R injury. Eighteen rats divided into 3 groups, equally. Group I rats were used as shams. For group II and III rats, they were prepared for transient global cerebral ischemia using a four-vessel-occlusion model. 5 mL/kg/h 0.9% sodium chloride was infused to the Group II and 3 microg/kg/h/5 ml dexmedetomidine was infused to the Group III for 2 h after I/R injury. The levels of MDA and NO and activities of SOD and CAT were measured in the left hippocampus tissue. The levels of TNF-alpha concentration were measured in the plasma. The number of apoptotic neurons was counted by TUNNEL method in histological samples of right hippocampus tissue. MDA and NO levels increased in Group II compared with Group I rats (p=0.002, p=0.002, respectively). In group III, MDA and NO levels decreased as compared to Group II (p=0.015, p=0.002, respectively). SOD and CAT activities increased in Group III as compared to Group II rats (p=0.002, p=0.002, respectively). The decrease in TNF-alpha levels of group III was significant as compared to group II (p=0.016). The number of apoptotic neurons in group III was lower than Group II rats. Our study showed that dexmedetomidine has a neuroprotective effect on hippocampus and dentate gyrus of rats after transient global cerebral I/R injury.

The neuroprotective effect of fish n-3 fatty acids in the hippocampus of diabetic rats.

INTRODUCTION: Diabetes mellitus may lead to functional and structural changes in the brain. Fish oil is a rich source of n-3 essential fatty acids (EFA) such as eicosapentaenoic and docosahexoenoic acids. We examined the neuroprotective effects of fish n-3 EFA in the hippocampus of diabetic rats. MATERIALS AND METHODS: Nineteen adult male rats were divided into three groups. Group I (control; n = 6) was fed a normal rat diet. Group II (diabetic; n = 6) was fed a normal rat diet and streptozotocin (STZ) was administered to induce diabetes mellitus. Group III (n-3 + diabetic; n = 7) was fed a normal rat diet and fish n-3 EFA (Marincap, 0.4 g/kg/day) for 8 weeks and STZ was administered to induce diabetes mellitus. The levels of malondialdehyde (MDA) and activities of superoxide dismutase (SOD) and catalase (CAT) were measured in the left hippocampus after the animals were sacrificed. The right hemisphere was completely blocked. The sections were stained with Cresyl Violet and apoptotic neurons were counted in the hippocampus. RESULTS: The levels of MDA and activities of SOD and CAT increased in diabetic rats compared to control rats. However, the levels of MDA and activities of SOD and CAT decreased in n-3 + diabetic rats compared to diabetic rats. Also, the number of apoptotic neurons increased in diabetic rats compared to control rats and decreased in n-3 + diabetic rats compared to diabetic rats. CONCLUSIONS: Fish n-3 EFA reduces oxidative stress and induces apoptotic changes in the hippocampus of STZ-diabetic rats. The addition of fish n-3 EFA to diets may be useful to prevent functional and structural changes to cerebral centers due to diabetes mellitus.

E-cadherin, beta-catenin adhesion complex and relation to matrilysin expression in pT3 rectosigmoid cancers.

E-cadherin/beta-catenin complex has a critical role in cell-cell adhesion. beta-Catenin is a critical component of the highly conserved Wnt signaling pathway that regulates cell proliferation and differentiation. Wnt signaling leads to the stabilization of cytosolic beta-catenin and to translocation to the nucleus, where it binds with T-cell factor and promotes the transcription and changes in target gene expression, including matrix metalloproteinases. In this study, we analyzed paraffin-embedded specimens from 42 patients with pT3 rectosigmoid cancer for E-cadherin, beta-catenin, and matrix metalloproteinase-7(MMP-7, matrilysin) expression using immunohistochemistry. Seventy-four and 79% of tumors expressed beta-catenin and E-cadherin, respectively. Nuclear expression of beta-catenin was detected only in 26.1% of tumors. Forty-five percent of the rectosigmoid cancers showed strong expression of MMP-7. It was revealed that membranous or cytoplasmic beta-catenin expression was significantly related to E-cadherin and MMP-7 expression. No significant association was seen between E-cadherin, beta-catenin, or MMP-7 expression and some clinicopathologic features. Our results may contribute to the functional interaction between beta-catenin and MMP-7. Further studies on Wnt/beta-catenin and MMP-7 gene activity and protein expression are necessary to better understand the pathogenesis of colorectal carcinoma.

Effect of diphenhydramine on myocardial injury caused by organophosphate poisoning.

BACKGROUND: The aim of this experimental study was to investigate whether diphenhydramine could prevent or diminish myocardial injury caused by organophosphate poisoning as defined by histologic findings and cardiac troponin I (cTnI) levels. METHODS: Twenty-four Sprague-Dawley rats were divided into equal three groups. Group 1 did not receive any agent during the experiment. Group 2 received 0.8 g/kg fenthion subcutaneously followed by normal saline (3 ml/kg) intramuscularly 30 minutes later. Group 3 received 0.8 g/kg fenthion subcutaneously, followed by diphenhydramine 30 mg/kg (in 3 ml/kg) intramuscularly 30 minutes later. All rats underwent laparotomy and thoracotomy while under anesthesia at 24 hours. RESULTS: Treatment with diphenhydramine significantly decreased the blood cTnI levels. Additionally, diphenhydramine significantly reduced myocardial injury, including edema, inflammation, vacuolization and necrosis, as determined by pathologic scoring. CONCLUSION: Organophosphate poisoning can cause myocardial injury as determined by measurement of I cTnI levels. Our study demonstrates that this injury can be attenutated by the administration of diphenydramine.

Influence of atropine therapy on fenthion-induced pancreatitis.

OBJECTIVE: We searched the influence of dose and timing of atropine therapy in fenthion-induced pancreatitis model. METHODS: All rats were intoxicated with fenthion except the control group. Two milligrams of atropine was administered for 24 hours in a high dose atropine group while a low dose atropine group received 100 micrograms of atropine for 24 hours. One group received 2 milligrams of atropine in the first four hours of intoxication while the other group received 2 milligrams of atropine in the last four hours before sacrifice. All rats were sacrificed 24 hours after intoxication. Pseudo-cholinesterase and lipase concentrations and histopathological markers of pancreatitis were studied. RESULTS: None of the models in this study completely prevented pancreatitis, however high dose atropine that is administered for 24 hours or the first four hours after intoxication prevented severe pancreatitis. CONCLUSION: Atropine administration influence on fenthion-induced pancreatitis should be studied for other organophosphates in animals and humans.

Technetium-99m diethylenetriaminepentaacetic acid radioaerosol scintigraphy in organophosphate induced pulmonary toxicity: experimental study.

BACKGROUND: The aim of this experimental study was to investigate pathological signs of lung damages caused by acute organophosphate (OP) poisoning by using Tc-99m DTPA radioaerosol scintigraphy and histopathological investigation. MATERIAL AND METHOD: Fourteen rabbits were divided into two equal groups (n = 7). Group 1 (control group) received normal saline (same volume of fenthion, 2 ml/kg) via orogastric tube. Group 2 (OP toxicity group) received 150 mg/kg of fenthion (diluted fenthion, 2 ml/kg) via orogastric tube. Six hours later, Tc-99m-DTPA aerosol inhalation lung scintigraphy was performed in both groups. Then all rabbits were anesthetized with ketamine hydrochloride (35 mg/kg, i.p.) and xysilazine (5 mg/kg, i.p.), and sacrificed by intracardiac blood discharge. The lungs were then removed. RESULTS: There was a significant difference in T1/2 values of Tc-99m DTPA clearance between control group and OP toxicity group (p = 0.04). Intraparenchymal vascular congestion and thrombosis, intraparenchymal hemorrhage, respiratory epithelial proliferation, number of macrophages in the alveolar, and bronchial lumen, alveolar destruction, emphysematous changes, and bronchoalveolar hemorrhage scores were significantly higher in the rabbits exposed to OP compared with the control group (p < 0.05). CONCLUSION: This study showed that OP toxicity caused a decrease in the alveolar clearance. Tc-99m DTPA radioaerosol inhalation lung scintigraphy was found to be a sensitive determination of acute lung damage in OP poisoning.