Diagnostic Value of Galectin-3 for Identifying Acute Pulmonary Embolism in the Emergency Department.

BACKGROUND: Pulmonary embolism (PE) is a common disease associated with high mortality and morbidity. Diagnosing PE is challenging due to diverse clinical presentations and the lack of specific biomarkers. OBJECTIVE: We hypothesized that plasma galectin-3 (Gal-3) levels might reflect the severity of acute PE and be useful for diagnostic assessment. METHODS: In this prospective study, 150 patients (100 patients with PE and 50 control patients) were included. Patients were stratified into high-risk, medium-risk, and low-risk groups according to the Wells and revised Geneva scoring systems, and Gal-3 levels were compared among the groups. PE was diagnosed by means of computed tomography pulmonary angiography. RESULTS: In this study, of the 100 PE patients included in the study, 69 patients recovered and were discharged and 31 patients died. Median Gal-3 value in the PE group was 27.0 ng/mL (range 11.5-35.0 ng/mL), whereas the median Gal-3 value in the control group was significantly lower at 8.8 ng/mL (range 1.0-21.0 ng/mL) (p < 0.001). When the Gal-3 values of the PE group and the control group were evaluated with the receiver operator characteristic curve, the area under the curve was calculated as 0.99 (95% confidence interval 0.979-1). At a Gal-3 cutoff value of 13.55 ng/mL, which was determined to be the most appropriate value for PE diagnosis, the sensitivity was 98% and the specificity was 92%. CONCLUSIONS: A biomarker that rapidly and accurately diagnoses acute PE in the emergency department can be an extremely useful tool. We concluded that plasma Gal-3 levels can be regarded as a promising marker of acute PE.

Sternal Fractures in Blunt Chest Trauma: Retrospective Analysis of 330 Cases.

OBJECTIVE: To analyse the range of injuries associated with sternal fracture (SF) and their clinical features and outcomes. STUDY DESIGN: Observational study. PLACE AND DURATION OF STUDY: Department of Emergency Medicine, Faculty of Medicine, Selcuk University, Konya, Turkey, from July 2010 to July 2020. METHODOLOGY: Sternal fractures were considered in 330 patients with blunt trauma during the study period. They were categorised according to the Johnson and Branfoot classification and the Arbeitsgemeinschaft fur Osteosynthesefragen / Orthopaedic Trauma Association classification. Demographic data were collected, including age, gender, mechanism of injury, associated injuries, and the length of hospital stay. RESULTS: During the 10-year study period, a total of 4024 thoracic trauma patients were admitted to the emergency department. Of these, 330 (8.2%) had a sternal fracture. The median age of the patients was 41 (8-90) years, and 72.7% were male. Isolated sternal fractures occurred in 93 patients (28.2%). An additional thoracic injury was observed in 74 patients (22.4%) included in the study, and an accompanying extrathoracic injury was observed in 34 patients (10.3%). In 129 patients (39.1%), both thoracic and extrathoracic pathologies were detected, in addition to SF. The mortality rate among patients with isolated sternal fracture was 1.1%; the mortality rate among patients with sternal fracture accompanied by additional pathologies was 6.6%. CONCLUSION: Sternal fractures are frequently associated with other injuries. Although isolated sternal fracture has a good prognosis, careful evaluation and clinical observation are essential for additional injuries. KEY WORDS: Emergency medicine, Sternal fracture, Chest trauma.

Dyspnoea and chest pain as the presenting symptoms of pneumomediastinum: two cases and a review of the literature.

Pneumomediastinum is the presence of air in the mediastinum. It may occur as spontaneous, traumatic, or iatrogenic pneumomediastinum. Although spontaneous pneumomediastinum is usually observed in healthy young men, traumatic pneumomediastinum may be caused by blunt or penetrating trauma to the chest and neck. Pneumomediastinum is a clinical condition with potential complications that cause high morbidity and mortality rates. Pneumomediastinum also may develop without tracheal or oesophageal injury after spontaneous or blunt chest, neck and facial injuries, and it may be accompanied by pneumothorax. We treated two patients who had pneumomediastinum. Case 1 was a 20-year-old man who had pain and dyspnoea around the sternum for one hour, as a result of a blow from an elbow during a football match. Case 2 was a 23-year-old man who had a two-day history of dyspnoea and chest pain with no history of trauma. In both patients, diagnosis of pneumomediastinum was confirmed with thoracic computed tomography scans, and the condition resolved within five days of in-patient observation. In conclusion, the diagnosis of pneumomediastinum should be considered for all patients who present to the emergency department with chest pain and dyspnoea.

Red cell distribution width and neurological scoring systems in acute stroke patients.

OBJECTIVES: The purpose of the present study was to evaluate the association between the red blood cell distribution width (RDW) and the Glasgow Coma Scale (GCS), Canadian Neurological Scale (CNS), and National Institutes of Health Stroke Scale (NIHSS) scores in patients who had acute ischemic stroke. METHODS: This prospective observational cohort study included 88 patients who have had acute ischemic stroke and a control group of 40 patients who were evaluated in the Emergency Department for disorders other than acute ischemic stroke. All subjects had RDW determined, and stroke patients had scoring with the GCS, CNS, and NIHSS scores. The GCS, CNS, and NIHSS scores of the patients were rated as mild, moderate, or severe and compared with RDW. RESULTS: Stroke patients had significantly higher median RDW than control subjects. The median RDW values were significantly elevated in patients who had more severe rather than milder strokes rated with all three scoring systems (GCS, CNS, and NIHSS). The median RDW values were significantly elevated for patients who had moderate rather than mild strokes rated by GCS and CNS and for patients who had severe rather than mild strokes rated by NIHSS. The area under the receiver operating characteristic curve was 0.760 (95% confidence interval, 0.676-0.844). Separation of stroke patients and control groups was optimal with RDW 14% (sensitivity, 71.6%; specificity, 67.5%; accuracy, 70.3%). CONCLUSION: In stroke patients who have symptoms <24 hours, the RDW may be useful in predicting the severity and functional outcomes of the stroke.

Neuroprotective effects of sildenafil in experimental spinal cord injury in rabbits.

Neuroprotective agents such as methylprednisolone and sildenafil may limit damage after spinal cord injury. We evaluated the effects of methylprednisolone and sildenafil on biochemical and histologic changes after spinal cord injury in a rabbit model. Female New Zealand rabbits (32 rabbits) were allocated to 4 equal groups: laminectomy only (sham control) or laminectomy and spinal trauma with no other treatment (trauma control) or treatment with either methylprednisolone or sildenafil. Gelsolin and caspase-3 levels in cerebrospinal fluid and plasma were determined, and spinal cord histology was evaluated at 24 hours after trauma. There were no differences in mean cerebrospinal fluid or plasma levels of caspase-3 between the groups or within the groups from 0 to 24 hours after injury. From 0 to 24 hours after trauma, mean cerebrospinal fluid gelsolin levels significantly increased in the sildenafil group and decreased in the sham control and the trauma control groups. Mean plasma gelsolin level was significantly higher at 8 and 24 hours after trauma in the sildenafil than other groups. Histologic examination indicated that general structural integrity was better in the methylprednisolone in comparison with the trauma control group. General structural integrity, leptomeninges, white and grey matter hematomas, and necrosis were significantly improved in the sildenafil compared with the trauma control group. Caspase-3 levels in the cerebrospinal fluid and blood were not increased but gelsolin levels were decreased after spinal cord injury in trauma control rabbits. Sildenafil caused an increase in gelsolin levels and may be more effective than methylprednisolone at decreasing secondary damage to the spinal cord. 

Pregnancy-associated plasma protein A and procalcitonin as markers of myocardial injury in patients with acute coronary syndrome.

BACKGROUND/AIM: To evaluate pregnancy-associated plasma protein A (PAPP-A), ischemia-modified albumin (IMA), procalcitonin, and troponin I levels as diagnostic markers of acute coronary syndrome in patients admitted to the emergency department. MATERIALS AND METHODS: The serum PAPP-A, IMA, procalcitonin, and troponin I levels were measured in 100 patients with acute coronary syndrome admitted to the emergency department and 100 healthy control subjects. RESULTS: Patients with acute coronary syndrome had significantly greater mean serum PAPP-A (patients, 10 ± 10 mIU/L; control subjects, 6 ± 10 mIU/L; P < 0.001), procalcitonin (patients, 2 ± 10 µg/L; control subjects, 0.4 ± 2 µg/L; P < 0.001), and troponin I levels (patients, 6 ± 8 µg/L; control subjects, 0.2 ± 0.3 µg/L; P < 0.001) than control subjects. There was no difference in mean IMA levels between patients and control subjects. There were no significant correlations between PAPP-A levels and IMA, procalcitonin, or troponin I levels in patients with acute coronary syndrome. CONCLUSION: The PAPP-A, procalcitonin, and troponin I levels were increased in patients with acute coronary syndrome. Therefore, elevated PAPP-A and procalcitonin levels, in addition to troponin I levels, may be useful markers of myocardial injury on admission to the emergency department.

Traumatic pneumorrhachis: 2 cases and review of the literature.

The presence of air in the spinal canal is known as pneumorrhachis (PNR), aerorachia, intraspinal pneumocele, pneumosaccus, pneumomyelogra, or intraspinal air. Pneumorrhachis may be iatrogenic, traumatic, and nontraumatic. We treated 2 patients who had posttraumatic PNR in the cervical spine region after stab injuries. Case 1 was a 31-year-old man who was stabbed in the C5 to C6 region. He had muscle weakness (3/5) and numbness on the right side of the body. Brain computed tomographic (CT) scan showed pneumocephalus, and cervical CT scan showed PNR at the C6 level. Treatment included observation, and symptoms and weakness improved within 7 days. Case 2 was a 40-year-old man who was stabbed in the C3 to C4 region. He had muscle weakness (1/5) and numbness on the left side of the body. Brain CT scan showed pneumocephalus, and cervical CT scan showed PNR at the C3 level. Cerebrospinal fluid drainage persisted, and he was treated with surgical repair of a dural laceration. Muscle strength improved. In summary, PNR is a rare condition that usually is treated nonoperatively. However, surgical treatment may be indicated for persistent neurologic symptoms or signs; the air detected in the spinal canal with radiographic imaging may be associated with an active cerebrospinal fluid leak and may cause spinal compression.

High-sensitivity C-reactive protein, lipoprotein-related phospholipase A2, and acute ischemic stroke.

BACKGROUND: Serum biomarkers may be useful for early diagnosis of acute ischemic stroke, exclusion of other diseases that may mimic stroke, and prediction of infarct volume. We evaluated serum high-sensitivity C-reactive protein (hs-CRP) and lipoprotein-related phospholipase A2 (Lp-PLA2) in patients who had acute ischemic stroke. METHODS: In 200 patients who presented to an emergency service (acute ischemic stroke, 102 patients; control with no stroke, 98 patients), stroke patients were evaluated with the Canadian neurological scale and diffusion-weighted magnetic resonance imaging, and all patients were evaluated with the Glasgow coma scale and their serum hs-CRP level and Lp-PLA2 activity were assessed. The volume of stroke lesions was calculated from magnetic resonance images. RESULTS: Patients who had stroke had higher mean serum hs-CRP level (stroke, 7±6 mg/dL; control, mean ± standard deviation 1±1 mg/dL; P≤0.001) and Lp-PLA2 activity (stroke, mean ± standard deviation 113±86 nmol/min/mL; control, mean ± standard deviation 103±50 nmol/min/mL; P≤0.001) than control patients who did not have stroke. The mean hs-CRP level and Lp-PLA2 activity were higher in patients who had greater stroke severity (lower Canadian neurological scale score) and were higher in patients who had larger volume strokes. CONCLUSION: Higher hs-CRP level and Lp-PLA2 activity are significantly associated with more severe neurologic impairment and larger infarct size in patients who have acute ischemic stroke. These biomarkers may be useful for rapid diagnosis and prediction of ischemic tissue volume in the early stage of ischemic stroke. These findings may be important for health care facilities that have limited access to emergency computed tomography scanning for the diagnosis of stroke.

Hemolysis associated with pneumatic tube system transport for blood samples.

OBJECTIVE: The frequency of hemolysis of blood samples may be increased by transport in a pneumatic tube system. The purpose of this study was to evaluate the effect of pneumatic tube system transport on hemolysis of blood samples. METHODS: Blood samples were transported from the emergency department to the hospital laboratory manually by hospital staff (49 patients) or with a pneumatic tube system (53 patients). The hemolysis index and serum chemistry studies were performed on the blood samples and compared between the different methods of transport. RESULTS: The blood samples that were transported by the pneumatic tube system had a greater frequency of hemolysis and greater mean serum potassium and median creatinine, aspartate aminotransferase, and lactate dehydrogenase levels than samples transported manually. CONCLUSION: Blood samples transported from the emergency department to the hospital laboratory by a pneumatic tube system may have a greater frequency of hemolysis than samples transported manually. This may necessitate repeat phlebotomy and cause a delay in completing the laboratory analysis.

Causes of poisoning in patients evaluated in a hospital emergency department in Konya, Turkey.

OBJECTIVES: To evaluate demographic and clinical characteristics of patients with poisoning at a community hospital. METHODS: The retrospective study comprised records of patients who were admitted to the emergency department of Konya Numune Hospital, Turkey, because of poisoning between January 1, 2009, and December 31, 2011. Data was evaluated for age, gender, educational status, occupation, arrival time, mechanism of intoxication , body temperature, pulse, respiratory rate, Glasgow Coma Scale score, treatment applied, duration of hospital stay, duration of follow-up, test results, final diagnosis, clinical disposition, and outcome. Agents causing the poisoning were also determined. RESULTS: Records of 1036 patients were evaluated. Of them, 764(74%) were female and 272(26%) were male. The predominant age range was 15-24 years in 617(60%) patients. The median time from substance exposure to admission to the emergency department was 2 hours. The most common cause of poisoning was attempted suicide in 955 [92%] patients and drug intoxication was the agent involved in 932 (90%). In the 15-24 year age range, there were 469 (76%) female patients. Of the total female population in the study, 716 (94%) attempted suicide. The median hospital stay was 24 hours. There were 908 (88%) patients who were advised to seek further evaluation at the psychiatry clinic, and 9 (0.9%) patients were admitted to the psychiatry inpatient units after medical treatment. In patients who were hospitalized and followed up, 1 (0.1%) died because of multiple drug poisoning. CONCLUSION: Most admissions to the emergency department for poisoning related to young women had used drugs during a suicide attempt.

Trauma in elderly patients evaluated in a hospital emergency department in Konya, Turkey: a retrospective study.

PURPOSE: Trauma is a common cause of admission to the hospital emergency department. The purpose of this study was to evaluate the cause of admission, clinical characteristics, and outcomes of patients aged ≥65 years admitted to an emergency department in Turkey because of blunt trauma. MATERIALS AND METHODS: Medical records were retrospectively reviewed for 568 patients (314 women and 254 men) aged ≥65 years who were admitted to an emergency department of a tertiary care hospital. RESULTS: Trauma was caused by low-energy fall in 379 patients (67%), traffic accident in 79 patients (14%), high-energy fall in 69 patients (12%), and other causes in 41 patients (7%). The most frequent sites of injury were the lower extremity, thorax, upper extremity, and head. The femur was the most frequent fracture site. After evaluation in the emergency department, 377 patients (66%) were hospitalized. There were 31 patients (5%) who died. Risk of hospitalization after trauma was significantly associated with trauma to the lower extremity, thorax, and spine; fractures of the femur and rib; and intracranial injury. CONCLUSION: Emergency department admission after trauma in patients aged ≥65 years is common after low-energy falls, and most injuries occur to the extremities. It is important to focus on prevention of falls to decrease the frequency of trauma in the elderly.

Levels of selenium, zinc, copper, and cardiac troponin I in serum of patients with acute coronary syndrome.

The aim of this study was to assess the levels of selenium (Se), zinc (Zn), copper (Cu), and troponin I (TnI) in patients with acute coronary syndrome (ACS) on admission to our emergency department in comparison to healthy control subjects. Patients with diagnosed ACS (n = 100) were included in the study group. Control subjects (n = 100) were selected from healthy volunteers in the same age range. Venous blood samples were obtained to evaluate the levels of Se, Zn, Cu, and TnI (on admission for the ACS group). Serum Se, Zn, and Cu levels were significantly less in the ACS group compared to the control group (p <0.001, p <0.01, and p <0.001, respectively). The serum TnI level was significantly greater in the ACS group compared to the control group (p <0.05). The serum Se level in the ACS group correlated significantly with the TnI level (r = -0.211, p = 0.035). These results indicate that Se, Zn, and Cu deficiencies may be risk factors for ACS, and a decreased serum Se level in patients with ACS might reflect the degree of myocardial necrosis.

Reversible myocarditis after spider bite.

Black widow spiders (Latrodectus tredecimguttatus) are poisonous spiders endemic in Turkey. Latrodectus bites may cause myocarditis with increased cardiac enzymes. We treated two men (aged 20 and 33 years) who had myocarditis after black spider bites with leucocytosis and elevated levels of troponin I, creatine kinase and creatine kinase-MB fraction. Both patients had normal results on an ECG, and one patient had abnormal echocardiography with minimal left ventricular wall movement disorder. Both patients were hospitalised in the intensive care unit and treated with intravenous fluids, analgesics, spasmolytic drugs, tetanus prophylaxis and cardiac monitoring. The levels of troponin I, creatine kinase and creatine kinase-MB fraction improved, and the patients were discharged home on the third and fifth hospital day without complications. Myocarditis after a Latrodectus bite is rare, but may be associated with serious complications. Therefore, in regions endemic with Latrodectus spiders, prudent treatment of spider bites may include cardiac evaluation and monitoring.

Seizures after overdoses of bupropion intake.

BACKGROUND: Bupropion is a new-generation monocyclic antidepressant that has been accidentally found to have potential effects on reducing nicotine addiction. It is structurally similar to stimulants such as amphetamine and inhibits dopamine and noradrenalin reuptake selectively. CASE REPORTS: We report two cases with no history of epilepsy who took oral bupropion for depression and had generalised tonic-clonic type of seizures in their follow-ups. CONCLUSION: After an overdose of bupropion, clinical effects are seen primarily on the neurological, cardiovascular, and gastrointestinal systems. Neurological effects can include tremor, confusion, agitation, hallucinations, coma, and seizures.

Cerebral infarction caused by traumatic carotid artery dissection.

Traumatic carotid artery dissection, if not diagnosed and treated early, is a serious problem with permanent neurological deficit and a high mortality rate of up to 40%. We present a case with delayed diagnosis of traumatic carotid artery dissection in a 21-year-old female. While there were no ischemic infarct findings on the admission cerebral computerized tomography (CT), such findings were observed on two cerebral CTs taken because of the left hemiplegia noticed seven days later when the patient regained consciousness. The patient was referred to our emergency service, and definitive diagnosis was achieved with arterial Doppler ultrasonography, cerebral magnetic resonance imaging (MRI), diffusion MRI, and MR angiography. We did not consider invasive treatment since the neurological damage was permanent and dissection grade was IV according to angiography findings. The case was discharged within a week and physiotherapy was advised. Despite the advances in diagnostic methods, diagnosis of traumatic carotid artery dissection is still missed or delayed, as in the case presented here. Early diagnosis can ameliorate permanent neurological damage or even prevent it. However, the vital factors for early diagnosis are the obtained anamnesis leading to appropriate radiological examinations, detailed physical examination and high clinical suspicion.

Inferior vena cava diameter as a marker of early hemorrhagic shock: a comparative study.

BACKGROUND: We determined the value of the inferior vena cava (IVC) diameter for predicting acute blood loss in control and blunt trauma patients and compared this with other parameters of hemorrhagic shock. METHODS: Fifty volunteers and 28 consecutive hemorrhagic shock patients were recruited prospectively to participate in the study. Vital signs, blood lactate, and serum bicarbonate were measured, and shock index and base excess were calculated. Anteroposterior (AP) and mediolateral (ML) IVC diameters during inspiration and expiration were measured in the right subcostal region. IVC diameters in hemorrhagic shock patients were compared with those of controls and were also compared with other hemorrhagic shock parameters. RESULTS: A significant relationship was determined between mean IVC AP and ML diameters during expiration and inspiration on admission in the study group and in the control group (p=0.000, p=0.000, p=0.000, p=0.000). Serum lactate levels correlated significantly with all IVC diameters (r=55), especially the IVC ML diameter during expiration. CONCLUSION: IVC diameter, as measured by transabdominal ultrasound, was more accurate than the shock index and other commonly used non-invasive predictors of acute blood loss (blood pressure, heart rate per minute, serum lactate level, base deficit).

Acute-phase vitamin B12 and folic acid levels in patients with ischemic and hemorrhagic stroke: is there a relationship with prognosis?

OBJECTIVE: The aim of this study was to investigate blood folic acid and vitamin B12 levels in patients with ischemic and hemorrhagic stroke patients and correlate these levels with prognosis. METHODS: Patients presenting within 3 hours of onset of ischemic or hemorrhagic strokes were approached for participation in the study. Diagnosis was made by clinical examination and head computed tomography scan. Venous blood samples were taken for determination of blood folic acid and vitamin B12 levels. Parameters were evaluated with respect to stroke type and according to Glasgow coma scale (< or =8 or > or =9). RESULTS: Eighty-seven patients with ischemic stroke (mean age: 65 +/- 10 years, 53% male) and 27 patients with hemorrhagic stroke (mean age: 60 +/- 10 years, 56% male) were included in the study. A significant direct correlation was found between Glasgow coma scale and mean plasma B12 levels in ischemic, but not hemorrhagic, stroke (r=112.75 and p=0.007, respectively). A significant direct correlation was found between Glasgow coma scale and mean plasma folic acid levels in hemorrhagic, but not ischemic, stroke (r=1.03 and p=0.017, respectively). In patients with Glasgow coma scale < or =8 (either hemorrhagic or ischemic stroke), a significant direct correlation was found between Glasgow coma scale and blood vitamin B12 levels. Vitamin B12 levels were significantly lower in patients with Glasgow coma scale < or =8 than in patients with Glasgow coma score > or =9 (p=0.04). CONCLUSIONS: In patients with ischemic stroke, low vitamin B12 levels, and in patients with hemorrhagic stroke, low blood folic acid levels, are associated with lower Glasgow coma scale values and higher hospital mortality.

Serum and cerebrospinal fluid magnesium levels, Glasgow Coma Scores, and in-hospital mortality in patients with acute stroke.

The aim of this study was to determine the relationship between serum and cerebrospinal fluid (CSF) magnesium(Mg+2) levels, Glasgow Coma Scores (GCS), and 7-day mortality in acute stroke patients. Patients with acute ischemic or hemorrhagic stroke arriving within the first 3 h of symptoms were included in the study. The control group consisted of healthy volunteers. GCS was determined, and blood and CSF samples were taken in order to establish serum and CSF glucose, Mg+2, sodium, potassium, calcium, and chlorine levels.Mortality was recorded at 7 days after admission. CSF Mg+2 in the ischemic infarct group was significantly lower than in the control group (p=0.006). CSF Mg+2 in the ischemic infarct patients with a GCS < or = 8 were significantly lower (p=0.002) than controls and in ischemic infarct patients with a GCS > or = 9. In the ischemic stroke patients, CSF Mg+2 and GCS were significantly correlated (r=55, p=0.031). CSF Mg+2 levels in ischemic stroke patients who died within 7 days were significantly lower than controls, ischemic stroke patients who survived, and hemorrhagic stroke patients who died (p=0.002, p=0.042, and p=0.005,respectively). Low CSF Mg+2 levels in patients with acute ischemic stoke at admission predicted a higher 1-week mortality.

Magnesium sulfate in emergency department patients with hypertension.

To compare the effect of IV magnesium with other antihypertensives in emergency department (ED) patients with hypertension. ED patients with a systolic BP > 135 mmHg or diastolic BP > 85 were approached for entry into the study. Those granting consent were randomly placed into one of three treatment groups: (1) 1.5 gm IV MgSO(4) (n = 42), (2) a parenteral or oral antihypertensive agent (n = 41), (3) both IV MgSO(4) and an antihypertensive agent (n = 44). Systolic and diastolic blood pressures were measured at entry into the study and at 15, 30, 45, and 60 min after magnesium or other antihypertensive medications were given. The main outcome measure was blood pressure at 60 min, and results were compared using one-way analysis of variance with the post hoc Tukey HSD test. Compared to systolic and diastolic blood pressures at time 0, both were lower at 15, 30, 45, and 60 min in all groups (p < 0.05). No significant difference in systolic or diastolic BP at any time point was observed when response to treatment was compared between the three groups. Intravenous MgSO(4) is as effective as antihypertensives at lowering BP in emergency department patients.

The effects of mannitol and melatonin on MRI findings in an animal model of traumatic brain edema.

OBJECTIVES: The aim of this study was to compare the effects of mannitol and melatonin on brain edema secondary to trauma using magnetic resonance imaging (MRI). METHODS: A mild traumatic brain injury with the Feeney method was performed upon twelve New Zealand rabbits. Three hours after the trauma was inflicted, MRI images were obtained, then the subjects were divided into two groups: a mannitol group and a melatonin group. The mannitol group (n = 6) was given 2 gr/kg of 20% mannitol IV over 10 minutes and the melatonin group (n = 6) received 100 mg/kg of melatonin IV over 30 minutes. Thirty-three hours after the first MRI, MRI was repeated. The 3-hour and 36-hour post-trauma MRI images in both groups were scored regarding signs of edema and extent of brain tissue protrusion in a blinded fashion by a staff radiologist. Intragroup and intergroup comparisons were made using the Fisher exact test and chi square test. Comparison of brain tissue protrusion measurements was done using the Mann Whitney U test. RESULTS: Signs of raised intraventricular pressure, contusion and parenchymal edema were more prevelant, and parenchymal protrusion was more prominent on the 36-hour MRI in both mannitol and melatonin groups. No significant difference was found between the melatonin and mannitol groups in any parameter in the MRI images performed 3 and 36 hours after the head trauma. CONCLUSIONS: In this animal model, melatonin and mannitol had similar effects on brain edema, as demonstrated on MRI 3 and 36 hours after head trauma.