Acute pulmonary embolism due to hydatic cysts

Transcription

1 Acute pulmonary embolism due to hydatic cysts Poster No.: C-1301 Congress: ECR 2016 Type: Scientific Exhibit Authors: M. Attia 1, M. Guerfel 2, H. Neji 2, S. Hantous-Zannad 2, I. Keywords: DOI: Baccouche 2, K. Ben Miled 2 ; 1 ARIANA/TN, 2 Tunis/TN Cancer, Biopsy, Ultrasound, MR, CT, Thorax, Neuroradiology brain, Lung /ecr2016/C-1301 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 16

2 Aims and objectives Hydatidosis is a parasitic infestation caused by Echinococcus granulosus's larva. It can be seen worldwide but it is more prevalent in the Mediterranean region [1]. Human infection is caused by contaminated food or by direct contact with infected canine. It affects most commonly the liver and the lung. Hydatid pulmonary embolism (HPE) is extremely rare even in endemic regions [1,2]. Imaging plays a critical role in the diagnosis of this potentially fatal condition. Although HPE is a relatively uncommon condition, it often manifests with specific imaging features that lead to a correct diagnosis [3]. Various imaging modalities can be used, but CT pulmonary angiography (CTPA) had rapidly become the imaging method of choice [3]. This study aims to: 1. Assess the value of CT scan in HPE detection. 2. Describe different types of HPE and illustrate CT abnormalities observed in acute HPE. Methods and materials Study population: Our database was retrospectively searched for all studies of CTPA performed in patients suspected of having acute pulmonary embolism (PE) in our hospital from 1989 to 2015.Only cases of HPE have been selected. All patients were admitted on an emergency basis. CT Imaging Technique: All studies were performed in a 16-slice detector scanner ( Brightspeed Elite, General Electric Medical System, Milwaukee). The CT scan coverage was determined based on the initial scout topographic images and extended from the thoracic inlet level through the lung bases. Contrast enhanced spiral CT was performed during suspended inspiration using 100KV, effective 394 mas and a pitch of A total volume of 80 ml of iodine-based nonionic contrast material (370 mg I/mL) was injected through an antecubital vein using a power injector at a rate of 4 ml/s. Page 2 of 16

3 A bolus tracking technique was used and the region of interest was placed in the right ventricle. Images were obtained with both lung and mediastinal window settings. Image interpretation: CT data were transferred to a workstation ( Advantage workstation 4.4, General Electric Health Care ). All CT images were reviewed on a workstation monitor and the interpretation was done in two steps: evaluation of heart and pulmonary arteries enhancement and assessment of pleuroparenchymal abnormalities. The diagnosis of acute HPE was made on the presence of an occlusion and/ or enlargement of the pulmonary arteries by cystic lesions with typical hypodense appearance. Multiplanar reconstruction (MPR) of CT images (figure 1) was used to permit threedimensional interpretation in order to precise the exact location and extent of the hydatid disease. Page 3 of 16

4 Fig. 1: CT Pulmonary Angiogram References: Department of Radiology,Abderahmen Mami Hospital,Ariana,Tunisia Results Population: The cohort included 31patients,18 male and 13 female (Table 1and figure 2 ), aged between 6 and 68 years. Table 1: distribution of population Frequence Pourcentage Page 4 of 16

5 Male Female Totale Fig. 2: Distribution of the population. References: Department of Radiology,Abderahmen Mami Hospital,Ariana,Tunisia Contribution of CTPA in HPE diagnosis: HPE wasn't suspected before doing CTPA. All patients were consulting for acute dyspnea. Page 5 of 16

6 Twelve patients had hemoptysis of low abundance. Diagnosis of HPE was suspected according to well-established semiological data. These imaging features were: occlusion and enlargement of the pulmonary arteries by cystic lesions with typical hypodense appearance leading to an intra- arterial image looking like "a rosary" [8-11 ]. Other types of pulmonary embolism such as thromboembolism or primary arterial neoplasm were discussed. It was a usual differential diagnosis [12]. The diagnosis of cruoric embolism could be made on the presence of central, partial or complete, defects within pulmonary arteries. Primary pulmonary arteries tumors appeared like a mildly enlarged and beaded arteries. This arterial's tissular content was enhanced after contrast injection [12]. Contribution of CTPA in the etiologic diagnosis of HPE : CTPA made the diagnosis of HPE in 31 patients. Patients were divided into three groups: The first group included patients with HPE secondary to cardiac hydatic cyst's rupture. The second group was composed of patients with HPE secondary to direct invasion of pulmonary artery by mediastinum or pericardium mass. The third group was composed of HPE's cases secondary to daughter cyst migration from liver into venous cava. Frequencies of each HPE type, detected on CT, are presented in figure 3. Page 6 of 16

7 Fig. 3: Different types of HPE: (A): HPE secondary to cardiac hydatic cyst's rupture, (B): HPE secondary to direct invasion of pulmonary artery by mediastinum or pericardium mass,(c) : HPE's cases secondary to daughter cyst migration from liver into vena cava. References: Department of Radiology,Abderahmen Mami Hospital,Ariana,Tunisia The first group:(figure 4 and 5) It was composed of 8 cases. HPE was secondary to cardiac hydatic cyst's rupture. It seems to be the most frequent etiopathogenic mechanism [6] However, it represents only 25.8% of all our patients CTPA showed hypodense and non enhanced mass of the right heart. Whatever a variety of tumors can be located in right heart chamber and must be considered in the differential diagnosis. Page 7 of 16

8 Association with typical cystic lesions in pulmonary artery, in our cases, made the diagnosis of HPE. Heart involvement represents less than 2% of all hydatic locations [4]. Hydatic cyst lies in left ventricle in (60% of cases), right ventricle (10%), pericardium (7%) and left atrial appendage (6%). Interventricular septum involvement is rare (4% of cases). Right ventricle localization is often subendocardial; rupture is more frequent than in left side leading to pulmonary embolism [5]. Cardiac MRI offers several advantages in cardiac hydatid cyst's diagnosis. It is a non-invasive technique allowing a precise tissue characterization. It provides also precise information concerning exact location. MR appearance of an hydatid cyst is usually characteristic: spherical lesion with signal intensity identical to cerebrospinal fluid associated with a hypointense rim on T2WI, which is believed to represent the pericyst consisting of dense fibrous capsule from reactive host tissue. Cardiac MRI was done in one patient in our study (figure 5). The second group:(figure 6) CTPA showed, In two patients, a mediastinal cystic mass invading pulmonary artery causing bilateral HPE.There was no associated liver or heart hydatid cyst. HPE by direct invasion of pulmonary artery is a very rare condition; in fact, to our knowledge, only one or two cases were previously published. Several hypotheses had been discussed; parasite can cross the arterial wall through small breaks of intima or by entering the vas nutritia [7]. The third group: (figure 7) It was composed of 21 cases.ctpa showed liver hydatid cyst associated with multiple cystic structures within the inferior vena cava secondary to ruptured hepatic hydatid cyst. In all cases HPE was bilateral involving multiple segmental and sub-segmental arteries. Hydatid cysts reach pulmonary arteries via the inferior vena cava and then the right side of the heart Page 8 of 16

9 CTPA did not show any cystic structures within the heart. In our study, pulmonary hydatid embolism secondary to ruptured hepatic cysts into systemic vascularisation represents 67.47% of all cases. It is therefore our most frequent mechanism; unlike published studies were ruptured primary cardiac cyst was the first hydatid way of spread [4]. Parenchymal and pleural findings in different groups:(figure 8) In all cases CT had shown multiples and bilateral hydatid cysts in different sizes. It demonstrated water attenuation (0-30 HU). In one case, cysts contained curvilinear and or ringlike wall calcification. In few cases (4 cases), parenchymal cysts were complicated by a bronchial rupture or a communication with pleura. Some other no specific pleural and parenchymal abnormalities were present in almost all patients with HPE such as pleural effusion, atelectasis, ground-glass attenuation and consolidation. Page 9 of 16

10 Fig. 4: CT pulmonary angiogram in axial (a and c) and sagittal (b) showing hydatic cystic mass localized in the right ventricular(red arrow) and complete occlusion of the left pulmonary artery by a mass ( blue arrow), with fluid density extending across the segmental arteries ( green arrows).it also show bilateral sub pleural hydatic cyst (yellow arrows). References: Department of Radiology,Abderahmen Mami Hospital,Ariana,Tunisia Page 10 of 16

11 Fig. 5: Chest radiography (a) : bilateral lung parenchymal hydatid cysts(white arrow).ctpa : (b and c): HPE in left upper segmental pulmonary artery(blue arrow) and hypodense mass localized in the right ventricular (red arrow).mr images (d) Steady-state free precession (SSFP) cine,showed hydatic mass localized in the right ventricular(red arrow) which had the characteristic signal intensity of a cystic lesion(red arrow). References: Department of Radiology,Abderahmen Mami Hospital,Ariana,Tunisia Page 11 of 16

12 Fig. 6: CT pulmonary angiogram in axial (b and c) view and coronal view (a)showing pericardial extracavitary hydatic mass (red arrow )compressing the left atrium and invading pulmonary artery (blue arrow) causing HPE in the right lower lobe( segmental pulmonary artery) ( green arrow). References: Department of Radiology,Abderahmen Mami Hospital,Ariana,Tunisia Page 12 of 16

13 Fig. 7: CT pulmonary angiogram in coronal(a), axial (b) and oblique view (c and d) showing multiple cystic structures within the inferior venous cava (red arrow) secondary to s liver hydatid cyst's rupture (blue arrow) with occlusion and enlargement of bilateral lung lower lobe segmental pulmonary artery (green arrow) by cystic lesions with typical hypodense content. References: Department of Radiology,Abderahmen Mami Hospital,Ariana,Tunisia Page 13 of 16

14 Fig. 8: CT imaging shows bilateral and multiple lung hydatid cysts (arrows). References: Department of Radiology,Abderahmen Mami Hospital,Ariana,Tunisia Conclusion Hydatid deseade is still endemic in certain parts of the world. It primarily affects the liver, but secondary Echinococcosis can develop in almost any anatomic location due to hematogenous dissemination. PHE is a rare and serious complication that can be life-threatening. CT angiography can clearly disclose cystic occlusion of the pulmonary artery and its branches as well as parenchymal and mediastinal hydatid localisations. Page 14 of 16

15 Early diagnosis, particularly in the acute form of pulmonary embolism, is of utmost importance because surgical intervention is the only potentially curative treatment. Personal information References 1. Moro P, Schantz PM. Echinococcosis: a review. Int J Infect Dis. 2009;13(2): Matossian RM, Rickard MD, Smyth JD. Hydatidosis: a global problem of increasing importance. Bull World Health Organ. 1977;55(4): Dursun M, Terzibasioglu E, Yilmaz R, Cekrezi B, Olgar S, Nisli K, et al. Cardiac hydatid disease: CT and MRI findings. AJR Am J Roentgenol. 2008;190(1): Buz S, Knosalla C, Mulahasanovic S, Meyer R, Hetzer R. Severe chronic pulmonary hypertension caused by pulmonary embolism of hydatid cysts. Ann Thorac Surg. 2007;84(6): Kaplan M, Demirtas M, Cimen S, Ozler A. Cardiac hydatid cysts with intracavitary expansion. Ann Thorac Surg. 2001;71(5): Odev K, Acikgozoglu S, Gormus N, Aribas OK, Kiresi DA, Solak H. Pulmonary embolism due to cardiac hydatid disease: imaging findings of unusual complication of hydatid cyst. Eur Radiol. 2002;12(3): Akgun V, Battal B, Karaman B, Ors F, Deniz O, Daku A. Pulmonary artery embolism due to a ruptured hepatic hydatid cyst: clinical and radiologic imaging findings. Emerg Radiol. 2011;18(5): Rossi SE, Goodman PC, Franquet T. Nonthrombotic pulmonary emboli. AJR Am J Roentgenol. 2000;174(6): Cook RJ, Ashton RW, Aughenbaugh GL, Ryu JH. Septic pulmonary embolism: presenting features and clinical course of 14 patients. Chest Kwon WJ, Jeong YJ, Kim KI, et al. Computed tomographic features of pulmonary septic emboli: comparison of causative microorganisms. Journal of Computer Assisted Tomography 2007;31(3): ;128(1): Page 15 of 16

16 11. Drira I, Fennira H, Hantous S, El Mokhtar E, Rekhis O,Haddoussa J, et al. Embolies pulmonaires hydatiques. Rev Pneumol Clin 2000;56: KARANTANAS A. H., BITSIOS G., KARAISKOU. Echinococcus of the pulmonary artery : CT, MRI and MRA findings. Comput Med Imag 2000;24: Page 16 of 16