Frequency and Predictors of Pulmonary Arterial Stump Thrombosis following Pneumonectomy or Lobectomy.

OBJECTIVES: Pulmonary artery stump thrombosis (PAST) following pneumonectomies/lobectomies is rare; its clinical importance is unknown. The objectives of this study were to analyze the prevalence and risk factors of PAST and the clinical significance in patients with pneumonectomy/lobectomy. METHODS: All adult cases who underwent pneumonectomy/lobectomy in our hospital for any reason and who underwent control contrast-enhanced thoracic CT during the follow-up period were included in the study. Demographic and clinical features of the patients, data on surgery, and the features of thrombi were recorded. RESULTS: During the 4-year study period, a total of 454 patients underwent pneumonectomy/lobectomy (93 pneumonectomy and 361 lobectomy). Among the patients, 202 patients (50 pneumonectomy and 152 lobectomy) with at least one follow-up thorax CT were included in the analyses. PAST was detected in 9 (4.5%) of 202 patients and mostly seen in patients with pneumonectomy (lobectomy: 2.6% vs. pneumonectomy: 10%, p = 0.043) and in patients whose pulmonary artery was ligated by using stapler (suture ligation 1% vs. stapler: 7.4%, p = 0.034). Pulmonary artery stump was also longer in patients with PAST (8.48 ± 11.22 mm vs. 23.55 ± 11.22 mm, p < 0.001). Univariate logistic regression analysis showed that pneumonectomy and longer pulmonary artery stump length were found to be significantly associated with PAST (p = 0.041 and p = 0.001, respectively). CONCLUSIONS: PAST was detected in 4.5% of our subjects undergoing lobectomy/pneumonectomy. PAST was found to be significantly higher in subjects who underwent pneumonectomy, those with longer pulmonary artery stump, and those with pulmonary artery stump ligated by using stapler.

Preoperative and postoperative assessment of temporal and masseter muscle size with magnetic resonance imaging in patients undergoing unilateral temporomandibular joint surgery.

The aim of this study was to assess any change between the preoperative and postoperative sizes of temporal and masseter muscles with magnetic resonance imaging (MRI) in patients undergoing unilateral temporomandibular joint surgery. This study was designed and implemented retrospectively. For clinical evaluation, a visual analog scale (VAS) and maximum mouth opening (MMO) were used. In order to make a preoperative diagnosis and perform a 6-month control, muscle size was measured in millimeters (mm) on T1 axial sections in MRI. Statistical analyses were performed using the SPSS 23.0 software package. Numeric variables were compared between two dependent groups using the Wilcoxon signed rank test. Statistical significance was set at p < 0.05. Twelve patients who underwent unilateral discectomy plus dermis-fat grafting, with classical preauricular inverse L incision, were included in the study, and data for eleven female patients were evaluated. The difference in size between the operated and non-operated sides was found to be statistically insignificant at the preoperative stage for both masseter muscle (operated side mM: 13.264 ± 1.822 mm; non-operated side mM: 13.264 ± 2.315 mm; pM = 0.929) and temporal muscle (operated side mT: 20.345 ± 2.609 mm; non-operated side mT: 20.582 ± 2.366 mm; pT = 0.594). There was a significant size reduction in the masseter muscle on the operated side in the postoperative period (preop mM: 13.264 ± 1.822 mm; postop mM: 12.036 ± 1.728 mm; pM = 0.018). Although there was also a size reduction in the operated side of the temporal muscle in the postoperative period, that difference did not reach statistical significance (preop mT: 20.345 ± 2.609 mm; postop mT: 19.445 ± 1.603 mm; pT = 0.182). On the non-operated side, there were no significant postoperative changes in the sizes of either the masseter muscle (preop mM: 13.264 ± 2.315 mm; postop mM: 12.682 ± 2.059 mm; pM = 0.248) or the temporal muscle (preop mT: 20.582 ± 2.366; postop mT: 19.891 ± 3.487 mm; pT = 0.625). Considering the study findings as a whole, a size reduction was observed in the operated side of the masseter muscle after TMJ surgery. The etiology of this change may be surgical trauma to the temporal and masseter muscles, skeletal alteration resulting from condylar change secondary to discectomy, and patients restraining themselves from application of maximum bite force as a result of a self-protection mechanism due to postoperative pain.

Impact of the HEAD-US Scoring System for Observing the Protective Effect of Prophylaxis in Hemophilia Patients: A Prospective, Multicenter, Observational Study

Objective: This study aimed to observe the preventive effect of prophylactic treatment on joint health in people with hemophilia (PwH) and to investigate the importance of integration of ultrasonographic examination into clinical and radiological evaluation of the joints. Materials and Methods: This national, multicenter, prospective, observational study included male patients aged ≥6 years with the diagnosis of moderate or severe hemophilia A or B from 8 centers across Turkey between January 2017 and March 2019. Patients were followed for 1 year with 5 visits (baseline and 3th, 6th, 9th, and 12th month visits). The Hemophilia Joint Health Score (HJHS) was used for physical examination of joints, the Pettersson scoring system was used for radiological assessment, point-of-care (POC) ultrasonography was used for bilateral examinations of joints, and the Hemophilia Early Arthropathy Detection with Ultrasound (HEAD-US) score was used for evaluation of ultrasonography results. Results: Seventy-three PwH, of whom 62 had hemophilia A and 11 had hemophilia B, were included and 24.7% had target joints at baseline. The HJHS and HEAD-US scores were significantly increased at the 12th month in all patients. These scores were also higher in the hemophilia A subgroup than the hemophilia B subgroup. However, in the childhood group, the increment of scores was not significant. The HEAD-US total score was significantly correlated with both the HJHS total score and Pettersson total score at baseline and at the 12th month. Conclusion: The HEAD-US and HJHS scoring systems are valuable tools during follow-up examinations of PwH and they complement each other. We suggest that POC ultrasonographic evaluation and the HEAD-US scoring system may be integrated into differential diagnosis of bleeding and long-term monitoring for joint health as a routine procedure.

Coronoid-temporalis pedicled rotation flap for middle skull base reconstruction.

We report on a patient who underwent maxillectomy and subsequent coronoid-temporalis flap reconstruction of the surgical defect to treat a maxillary sinus carcinoma invading the middle skull base. The patient underwent successful reconstruction of the middle skull base and displayed acceptable functional result. Middle skull base defects can be successfully repaired using a local coronoid-temporalis pedicled flap. The coronoid process of the mandible is advantageous as a local flap because it is close to the skull base defects and can easily be dissected from adjacent tissues. The use of a coronoid-temporalis pedicled flap offers excellent results without the need for further extensive surgery.

Quantitative measurement of radiofrequency volumetric tissue reduction by multidetector CT in patients with inferior turbinate hypertrophy.

OBJECTIVE: To objectively assess the efficacy of radiofrequency thermal ablation of inferior turbinate hypertrophy. METHODS: Thirty-five patients with nasal obstruction secondary to inferior turbinate hypertrophy were prospectively enrolled. Radiofrequency energy was delivered to four sites in each inferior turbinate. Patients were evaluated before and 8 weeks after intervention. Subjective evaluation of nasal obstruction was performed using a visual analogue scale (VAS), and objective evaluation of the turbinate volume reduction was calculated using multidetector CT. Volumetric measurements of the preoperative inferior turbinate were compared with postoperative values on both sides. RESULTS: The great majority of patients (91.4%) exhibited subjective postoperative improvement. Mean obstruction (VAS) improved significantly from 7.45±1.48 to 3.54±1.96. Significant turbinate volume reduction was achieved by the surgery on both right and left sides [(preoperative vs. postoperative, right: 6.55±1.62cm(3) vs. 5.10±1.47cm(3), (P<0.01); left: 6.72±1.53cm(3) vs. 5.00±1.37cm(3), (P<0.01)] respectively. CONCLUSION: Radiofrequency is a safe and effective surgical procedure in reducing turbinate volume in patients with inferior turbinate hypertrophy. Multidetector CT is an objective method of assessment in detecting radiofrequency turbinate volume reduction.

Neurocytoma arising in an adrenal gland mature teratoma.

Mature teratoma of adrenal gland is a rare entity. Neurocytoma is a low grade neuronal tumor even rarely seen among central nervous system tumors. Nervous system tumors arising in teratomas are frequently originated from glial or primitive neuroectodermal cells. Here we report a neurocytoma arising in mature cystic teratoma in the right adrenal gland of an 8 years old boy. Histological examination revealed a tumor composed of solid sheets in fibrillar basis with small uniform cells in the neuroglial tissue in teratoma. This is only the second case demonstrating a neurocytoma arising in a mature cystic teratoma in the literature.

The role of risk factors in delayed diagnosis of pulmonary embolism.

BACKGROUND: Despite diagnostic advances, delays in the diagnosis of pulmonary embolism (PE) are common. OBJECTIVE: In this study, we aimed to investigate the relationship between delays in the diagnosis of PE and underlying risk factors for PE. METHODS: We retrospectively evaluated the records of 408 patients with acute PE. Patients were divided into 2 groups, surgical or medical, based on risk factors leading to the embolism. Analysis involved demographic characteristics of the patients, dates of symptom onset, first medical evaluation, and confirmatory diagnostic tests. Diagnostic delay was described as diagnosis of PE more than 1 week after symptom onset. RESULTS: The mean time to diagnosis for all patients was 6.95 ± 8.5 days (median, 3 days; range, 0-45 days). Of the total number of patients, 29.6% had presented within the first 24 hours and 72.3% within the first week. The mean time to diagnosis was 4.4 ± 7.6 days (median, 2 days; range, 0-45 days) in the surgical group and 8.0 ± 8.6 days (median, 4 days; range, 0-45 days) in the medical group (P = .000). The mean time to diagnosis in the medical group was approximately 4 times greater than that of the surgical group on univariate analysis. Early or delayed diagnosis had no significant impact on mortality in either group. CONCLUSION: Delay in the diagnosis of PE is an important issue, particularly in medical patients. We suggest that a public health and educational initiative is needed to improve efficiency in PE diagnosis.

Combined risk stratification with computerized tomography /echocardiography and biomarkers in patients with normotensive pulmonary embolism.

BACKGROUND: Right ventricular dysfunction (RVD) detected by computerized tomography (CT)/echocardiography or elevated biomarkers is associated with a poor prognosis for pulmonary embolism (PE). However, these prognostic factors have not previously been concomitantly elucidated in the same patient group. METHODS: This prospective study included 108 consecutive patients with normotensive PE confirmed by CT pulmonary angiography (CTPA). On admission, patient serum NT-proBNP and troponin T (Tn-T) levels were measured, and echocardiography was performed within 24 hours after diagnosis of PE. Receiver operating characteristic (ROC) analysis was performed to determine the optimal echocardiographic end-diastolic diameters of the right ventricle, the ratio of the right ventricle to left ventricle (RV/LV ratio) on CTPA, and NT-proBNP and Tn-T cut-off levels with regard to prognosis. RESULTS: All-cause 30-day mortality was 13% and PE-related mortality was 5.6%. RVD was defined as a right/left ventricular dimension ratio≥1.1 on CTPA and RV>30 mm on echocardiography by ROC analysis. A cut-off level of NT-proBNP≤90 pmol/ml had a high positive predictive value of 98% for survival, whereas NT-proBNP>300 and Tn-T≥0.027 had a negative predictive value, for all-cause deaths, of 95% and 96%, respectively. PE mortality in patients with NT-proBNP>300 and Tn-T≥0.027 reached 64%. In univariable analysis, the combination of Tn-T≥0.027 ng/ml with a echocardiographic RVD were the most significant predictors of overall mortality and PE-related death [HR: 14 (95% CI: 4.6-42,) and HR: 37.6 (95% CI: 4.4-324)], respectively. In multivariable Cox's regression analysis, NT-proBNP>300 and Tn-T≥0.027 HR: 26.5 (95% CI: 4.1-169.9, p<0.001) were the best combination to predict all-cause of mortality. CONCLUSIONS: The combination of NT-proBNP and Tn-T clearly appears to be a better risk stratification predictor than biomarkers plus RVD on CT/ echocardiography in patients with normotensive PE.

Investigation of relationship between the D-dimer and ischemia-modified albumin levels with the radiological imaging-based pulmonary embolism severity score in acute pulmonary embolism.

OBJECTIVE: To investigate possible relationship between the D-dimer and ischemia-modified albumin (IMA) levels and radiological imaging-based severity scores in pulmonary embolism (PE) based on two different radiological characteristics; the pulmonary arterial obstruction index (PAOI) and the right ventricle/left ventricle (RV/LV) ratio. METHODS: In this prospective cohort study, forty-seven patients presenting to the emergency department and definitively diagnosed with PE using spiral computerized tomography (CT) were initially enrolled in the study. Levels of IMA and D-dimer were assessed colorimetrical and immuno-turbidimetric methods, respectively. The PAOI and RV/LV ratios were calculated from CT images. The levels of biochemical parameters between the groups were compared with use of Mann-Whitney U and Kruskal-Wallis tests and relationship between the radiological scores were assessed using the Spearman correlation test. RESULTS: Analysis of the calculated PAOI and RV/LV ratio revealed a significant correlation between them (r=0.36, p=0.023). D-dimer levels differed considerably among the mild (=40%), moderate (40%-60%) and severe (60%) groups constituted on the basis of PAOI (p=0.039). This difference stemmed from those in D-dimer levels in the mild group, PAOI =40 % and the severe group, PAOI 60% (p=0.02; Z= -2.328). In addition, D-dimer levels and PAOI revealed a positive correlation, but no similar correlation was determined between D-dimer levels and RV/LV. There were no significant correlations between IMA and D-dimer levels, PAOI and RV/LV ratios. CONCLUSION: In the biochemical determination of severity of PE based on radiological characteristics, D-dimer may be a more relevant marker than IMA, which has been proposed as a new marker.

A comparison of the effects of ramipril and losartan on blood pressure control and left ventricle hypertrophy in patients with autosomal dominant polycystic kidney disease.

BACKGROUND: Hypertension is frequently seen in autosomal dominant polycystic kidney disease (ADPKD), and it has a negative effect on renal progression. Hypertension and left ventricle hypertrophy (LVH) are related in terms of pathogenesis and their effects on renal progression. In this study, we aimed to compare the effects of losartan and ramipril on blood pressure (BP) control, LVH, and renal progression in patients with hypertensive ADPKD. METHODS: Thirty-two ADPKD patients with ages ranging between 18 and 70 years who were stage 1-2 hypertensive were included in this study. Routine biochemical tests and echocardiography were obtained at first examination of the patients. Following these, the patients were randomized. One group was given losartan and the other ramipril. They were followed up for 1 year, and their echocardiographies and routine biochemical tests were repeated at the end of the year. RESULTS: BP values decreased in both the groups at the end of the first year (p < 0.001). There was a statistically significant difference in LVH in both the groups at the end of the first year than at the beginning (losartan, p = 0.007; ramipril, p < 0.001). CONCLUSIONS: In this study, effective BP control was obtained with losartan and ramipril and LVH was found to be regressed significantly in the hypertensive patients with ADPKD. These two groups of antihypertensive drugs may also have beneficial effects on the retardation of renal progression and in reducing cardiovascular mortality in hypertensive patients with ADPKD.

MR spectroscopic evaluation of psychomotor delay of unknown cause in children.

OBJECTIVE: The aim of this study was to use MR spectroscopy to determine whether the brain metabolism of children with psychomotor delay of unknown cause differs from that of children without psychomotor delay. SUBJECTS AND METHODS: Twenty children (10 girls, 10 boys; mean age, 8.65 years; range, 4-15 years) with psychomotor delay and 19 children without psychomotor delay who served as controls (nine girls, 10 boys; mean age, 8.79 years; range, 6-13 years) were evaluated with multivoxel MR spectroscopy of the brain. The Stanford-Binet test and Wechsler Intelligence Scale for Children-Revised were used to evaluate developmental quotient. Psychomotor delay was assessed as severe (developmental quotient, < 50), moderate (developmental quotient, 50-75) and mild (developmental quotient, > 75). The controls had a developmental quotient greater than 95. Spectra were acquired from eight specific voxels at the bilateral parasagittal frontal and parietal gray matter and the bilateral frontal and parietal white matter at the level of the centrum semiovale. The ratios of N-acetylaspartate (NAA) to choline (Cho), NAA to creatine (Cr), and choline to creatine were determined. RESULTS: Thirteen children had minor and seven children had moderate psychomotor delay. In the psychomotor delay group, the right frontal white matter NAA/Cho, NAA/Cr, and Cho/Cr ratios were 1.45 +/- 0.18, 1.95 +/- 0.33, and 1.36 +/- 0.27; in the control group the ratios were 1.46 +/- 0.23, 2.04 +/- 0.33, and 1.41 +/- 0.19. The ratios for the left frontal lobe white matter were 1.34 +/- 0.21, 2.01 +/- 0.33, and 1.55 +/- 0.26 in the psychomotor delay group and 1.42 +/- 0.15, 2.17 +/- 0.34, and 1.53 +/- 0.25 in the control group. The ratios for the right parietal lobe white matter were 1.80 +/- 0.38, 2.04 +/- 0.43, and 1.18 +/- 0.35 in the psychomotor delay group and 1.89 +/- 0.31, 2.16 +/- 0.30, and 1.17 +/- 0.23 in the control group. The left parietal lobe white matter ratios were 1.66 +/- 0.36, 2.08 +/- 0.35, and 1.35 +/- 0.29 in the psychomotor delay group and 1.81 +/- 0.29, 2.17 +/- 0.35, and 1.22 +/- 0.26 in the control group. CONCLUSION: Metabolite distribution varied with brain region in children with and those without psychomotor delay. No significant difference was found between the brain metabolite ratios of children with psychomotor delay of unknown cause and those of age-matched children without psychomotor delay.

A case of intratracheal schwannoma presenting at the emergency department with a diagnosis of asthmatic attack.

Primary tumors of the tracheobronchial tree are rare, and benign tumors are even rarer. Patients with tracheobronchial tumors are at times wrongly diagnosed with asthma. A 77-year-old woman presented to our Emergency Department with increasing dyspnea and stridor. She had been treated for bronchial asthma for the last 7 years. Due to the presence of the stridor, a cervical soft tissue computed tomography scan was performed. It revealed a tracheal polyp at the level of the thyroidal isthmus. Polyp excision with rigid bronchoscopy was performed by a thoracic surgeon. This case demonstrates that intratracheal masses should be considered in patients with dyspnea and stridor or in patients with asthma refractory to usual treatment.

Isolated interrupted aortic arch: in a 40-year-old adult.

Interrupted aortic arch (IAA) is a scarce and generally lethal congenital malformation. Patients with complete IAA scarcely reach adult age without previous surgical intervention. In this case, we presented a 40-year-old isolated IAA case with hypertension and angina pectoris. IAA just distal to left subclavian artery and markedly developed collateral circulation was demonstrated via cardiac catheterization (CC) and multi-slice computed tomography angiography (MSCT).

Adult-type anomalous origin of the left coronary artery from the main pulmonary artery: one case report.

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital defect that presents even less frequently in adults. Here we described a 40-year-old patient presenting with palpitations. Electrocardiography revealed frequent ventricular ectopy. Echocardiography revealed a dilated left ventricle and an abnormal flow pattern in the pulmonary artery and at the right side of the interventricular septum. Coronary angiography demonstrated an enlarged right coronary artery (RCA) with collateralization to the left coronary artery (LCA) and reflux of contrast into the pulmonary artery. Computed tomography confirmed ALCAPA syndrome. Surgical corrections were planned.

Mediastinal lymph nodes: assessment with diffusion-weighted MR imaging.

PURPOSE: To prospectively determine whether the diffusion-weighted magnetic resonance imaging is useful to distinguish between malignant and benign mediastinal lymph nodes. MATERIALS AND METHODS: Thirty-five patients (14 women, 21 men; mean age 52 years) with 91 lymph nodes in the mediastinum detected by computed tomography underwent 1.5 Tesla (T) diffusion-weighted MR imaging before mediastinoscopy (n = 29) and mediastinotomy (n = 6). Diffusion-weighted MR images were acquired with a b factor of 50, and 400 s/mm(2) using single-shot echo-planar sequence. RESULTS: Of the 35 patients, 18 had diagnosis of malignant tumor. Of the 18 patients with tumor, 8 had nonsmall cell carcinoma, and 10 had small cell carcinoma. Ninety-one mediastinal lymph nodes were detected in the 35 untreated patients: 19 were pathologically diagnosed as metastatic lymph nodes, and 72 lymph nodes were diagnosed as nonmetastatic lymph nodes, including 50 sarcoidosis, 14 reactive lymphoid hyperplasia, and 8 necrotizing granulamatous lymphadenitis. The apparent diffusion coefficient (ADC) was significantly lower in metastatic lymph nodes (1.012 +/- 0.025 x 10(-3) mm(2)/s; P < 0.0005) than in benign lymph nodes (1.511 +/- 0.075 x 10(-3) mm(2)/s). On the ADC map, malignant nodes showed hyperintense (n = 2, 10.52%), hypointense (n = 14, 73.68%), and mixed intensity (n = 3; 15.78%), whereas benign nodes showed hyperintense (n = 57; 79.16%), hypointense (n = 3; 41.6%), isointense (n = 6; 8.33%), and mixed intensity (n = 6; 8.33%). CONCLUSION: Diffusion-weighted MR with ADC value and signal intensity can be useful in differentiation of malignant and benign mediastinal lymph nodes.

Mediastinal lipoblastoma causing diaphragmatic eventration: a case report and review of the literature.

Lipoblastomatous tumors are quite rare neoplasms derived from embryonic white fatty tissues. The majority is seen in infancy and early childhood. Generally they arise in extremities. Here, we present a 12-month-old female infant presenting with a mediastinal and cervical mass, showing left diaphragmatic eventration. We reviewed these cases and discussed clinical manifestations, radiologic, and histopathologic findings and treatment of these tumors.

Magnetic resonance imagination of the peroneus longus tendon after anterior cruciate ligament reconstruction.

Several studies report that tendons can regenerate after harvesting. These studies have been performed especially in patellar and hamstring tendons. At our institution, 10 cm length of full thickness peroneus longus tendon has been harvested to reconstruct torn anterior cruciate ligament since 1997 as a different graft source. The aim of this study was to investigate whether the peroneus longus tendon used the anterior cruciate ligament reconstruction has a regeneration potential or not. Twelve patients, who had originally undergone harvesting of the peroneus longus tendon for the primary surgery of the anterior cruciate ligament reconstruction, underwent magnetic resonance imaging (MRI). Images of both legs were acquired simultaneously with the use of the scanner's extremity coil, as we aimed to compare harvested peroneus longus tendon with the other leg's peroneus longus tendon (healthy side) for evaluation of the regeneration potential. The average age of the patients was 31 years. There were eight right and four left legs. The average time interval was 52 months between ligament surgery and MRI. In all patients, a varying amount of the regeneration of the peroneus longus tendon was seen on the MRI images. Although the extent of PLT regeneration in proximal sections seemed better than in mid- and distal sections, there was no statistical difference between sections (P = 0.130). These data show that the peroneus longus tendon has a regeneration potential after harvesting for anterior cruciate ligament reconstruction.

Time delay between onset of symptoms and diagnosis in pulmonary thromboembolism.

BACKGROUND: Although pulmonary thromboembolism is usually considered as an acute illness, delayed presentations are fairly common. OBJECTIVE: The purpose of this study was to investigate delays to presentation/diagnosis and their likely correlation with patients' clinical and radiographic findings in pulmonary thromboembolism. METHODS: All cases of pulmonary embolism diagnosed in our hospital between March 2002 and May 2006 were reviewed for the date of symptom onset, the dates of presentation and diagnosis, clinical findings, localization of embolism in pulmonary vascular tree and pleuropulmonary changes arising secondary to thrombotic occlusion. The parameters related to presentation delays were analyzed using a Mann-Whitney U test and logistic regression analysis. RESULTS: Of the 178 patients enrolled, 30.4% presented to hospital 1 week after the start of their symptoms and there was an average of 8.4 +/- 11.4 days' (median 4 days, range 0-75) delay to presentation. The delay from presentation to diagnosis was 0.9 +/- 1.9 days (median 0, range 0-16). Patients with hypotension, respiratory rate >20 and atelectasis in spiral CT presented earlier. However, no correlation was found between delays and the level of thromboembolic occlusion in pulmonary artery. CONCLUSION: Pulmonary thromboembolism should be considered not only in an acute setting, but also in patients with prolonged respiratory symptoms, since there was a significant delay to presentation amongst our patients. The presence of hypotension and a high respiratory frequency was clearly associated with early presentation.

Meteorological parameters and seasonal variations in pulmonary thromboembolism.

BACKGROUND AND OBJECTIVES: In recent years, circannual variations in incidence and mortality for venous thromboembolic disease have been demonstrated, with a peak in winter. However, several investigators have observed no seasonal variation in these diseases. The aim of our study was to investigate whether a seasonal variation, in terms of atmospheric pressure, humidity, and temperature, exists for pulmonary thromboembolism. METHOD: We retrospectively included 206 patients with a diagnosis of pulmonary embolism (PE) between 1 June 2001 and 31 May 2006. RESULTS: The highest number of cases in the 5 years concerned occurred in May (29 cases). Although PE occurred most commonly in the spring (72 cases) and autumn (51 cases), the difference was statistically significant (P = .003). There were no case correlations with months and pressure, temperature, or humidity. However, there was a statistically significant positive correlation between case incidence and atmospheric pressure (r = 0.53, P < .0005) and humidity (r = 0.57, P < .0005). In terms of risk factors, seasonal distribution was not statistically significant as regards cases of embolism occurring for surgical or nonsurgical reasons (r = 0.588). CONCLUSION: In terms of the relationship between seasons and embolism cases, despite the determination of an insignificant positive correlation, a statistically significant positive correlation was determined between air pressure and humidity and case incidence. There is now a need for further wide-ranging prospective studies including various hematological parameters to clarify the correlation between PE and air pressure.