Percutaneous treatment of hydatid cyst

Clinical History

A 10-year -old boy presented with left sided chest pain. Chest x-ray rvealed two radioopacities in left hemithorax. Thoracic CT examination was performed.

Imaging Findings

The patient presented with left sided chest pain. Chest X-ray revealed two nodular opacities in right lung. Thorax CT revealed two cysts in left lower lobe of lung (Fig. 1a,b). One was located in between heart and anterolateral chest wall and protruding through the intercostal space into subcutaneous tissue. The other one was located posterolaterally and basally adjacent to pleura.Densities of the anterior and posterior cysts were 24 HU and 14 HU, respectively. Ultrasonography showed that cysts had a double contoured intact wall and did not contain any daughter cysts. With these findings on ultrasonography and CT hydatid disease was considered as diagnosis. Our patient had two pulmonary hydatid cysts located subpleurally which were treated percutaneously. PAIR (pucture-aspiration of cyst contents-injection of hypertonic saline solution-reaspiration) technique was used for the procedure under ultrasonography and fluoroscopy guidance. An 18-gauge Seldinger needle was used for puncturing cyst hydatid and cyst content was aspirated. Then hypertonic saline was instilled and kept in cavity for 5-10 min. Finally saline solution was aspirated and after evacuating the cystic content, the needle was withdrawn. No procedure related complication was encountered in this patient. CT examination obtained one week after treatment revealed air filled cavity, which persisted for almost one year (Fig. 1c). During 5 years follow up, no signs of recurrence or viability of the cysts were observed.

Discussion

Most of the patients with hydatid disease of the lungs have multiple round cystic lesions at CT imaging, that are virtually pathognomonic of hydatid disease. The majority of cysts are unruptured at the lung bases and at the posterior segments. Treatment of choice in pulmonary hydatid cyst is medical therapy with albendazole or mebendazole. In unresponsive patients surgical treatment is the conventional treatment. However in large surgical series, postoperative complications are seen in 3.5% of patients and the reported mortality rate is 1.7-2%. In addition no reliable long term follow up data exists about the recurrence rate. Transthoracic aspiration of a pulmonary hydatid cyst was first reported in early 1980. After the first report several case reports about unintentional aspirated hydatid cysts appeared in the literature. The first systematic study and the largest series was reported by Akhan et al. They treated 11 hydatid cysts of 8 patients that were resistant to medical therapy. They used PAIR technique as in our case for treatment and cure rate was 91 %. In our case volume reduction of 88 and 60 percent is observed at 5 years after the procedure. Significant size and volume reduction , absence of fluid component, calcification and thick irregular contour of the wall are observed for both of the cysts which are signs of healing. Control Thoracic CT examination (Fig. 3a,b) clearly depicted almost complete resolution and remnant of the hydatid cysts at 5 years follow up. Percutaneous treatment is a well established treatment method for liver hydatid cysts. Percutaneous treatment of lung hydatid cysts could be used in inoperable patients or in patients who refuse surgery. It emerges also as an alternative treatment in peripherally located cysts which allows an easy access via percutaneous route without traversing lung parenchyma.

Differential Diagnosis List

Final Diagnosis

PERCUTANEOUS TREATMENT OF THORACIC HYDATID CYSTS

URL:	https://www.eurorad.org/case/692
DOI:	10.1594/EURORAD/CASE.692
ISSN:	1563-4086