However, pre-operative diagnosis of pelvic hydatid diseases can be possible with imaging study such as USG, CT scan by noting features such as multilocular appearance, cyst wall calcification, a fluid level from hydatid sand
and the ultrasonic water lily sign.
Intercystic spaces were filled with homogenous echogenic material (hydatid sand
) predominantly seen in the centre of the lesion, creating rosette appearance (wheel-spoke pattern) (Figure 2).
Still relayed on ultrasound examination, this classification recognizes six categories of hydatid cysts: CL, a simple cyst with anechoic content and not clearly visible wall, suspicious for an early stage of EC; CE1, a cyst with visible wall containing an inhomogeneous fluid due to the presence of hydatid sand
; CE2, a multiseptate cyst with daughter cysts inside, with variable appearance ("rosetta-like," "wheel-like," or "honeycomb-like" structure); CE3, characterized by anechoic content with detached membranes within (3a) or daughter vesicle inside solid-echoic areas (3b), related to degenerated daughter cysts; CE4, hypoechoic or inhomogeneous content without daughter cysts; CE5, with thick calcified wall with a cone shadow.
Protoscolex obtained from hydatid sand
of a human hydatid cyst.
If removed, the cyst will consist of 3 layers (innermost germinal layer, intermediate laminated membrane, and outer fibrous layer) and contain protoscolices (attached or separated) with a double row of refractile, birefringent, acid-fast hooklets 22 to 40 [micro]m in size and 4 round suckers that comprise the "hydatid sand
." Finally, in a young patient with splenic lymphangioma, the diagnostic evaluation should be extended to include extrasplenic organs because it has been observed that in younger patients the likelihood of multiorgan involvement is greater.
Ultrasonography (US) is particularly helpful in the detection of daughter cysts internal membranes and hydatid sand
. Computed tomography (CT) is important in evaluation of calcification and cyst infection.
Solitary anechoic lesions are typical findings on ultrasonography, rarely mixture of infolded membranes, scoleces, and hydatid sand
may produce a highly echogenic (solid) pattern on sonography because of the large acoustic impedance differences between the intracystic components.
The liquid of the cysts resembled hydatid sand
. The authors stated that the cuticle of the larva was very thin and that this "reminded us that in Echinococcus granulosus this cuticle may reach several millimeters." The inner surface of the cysts contained a proliferative membrane with many vesicles and protoscolices, the larval stage of tapeworms.
(24,25) A simple cyst on ultrasound may contain multiple mobile echogenic foci (hydatid sand
), which enables differentiation from a congenital simple cyst.
The "Falling snowflakes" sign, which is characterized by multiple echogenic foci of hydatid sand
, is a pathognomonic finding for hydatid cyst.
Telescope was reintroduced through the trocar into the cavity to confirm any remnants of daughter cysts, hydatid sand
and to confirm for any cysto-biliary communication.
USG is most sensitive in detection of membrane, septa and hydatid sand