Fine needle aspiration cytology of bursal cyst.

OBJECTIVE

To evaluate the cytomorphology of bursal cyst and assess the efficacy of aspiration cytology in its diagnosis and treatment.

STUDY

DESIGN

Nineteen cases of bursal cyst seen over four years were studied. Material was obtained by fine needle aspiration. The smears were stained with May-Grünwald-Giemsa stain and hematoxylin and eosin.

RESULTS

Eight cysts were in the popliteal fossa, 4 on the elbow, 3 on the knee, 2 on the shoulder and 2 in the calf. Gelatinous material was aspirated in all the cases. In some cases the cyst collapsed after aspiration. The key diagnostic features were hypocellular smears in a mucoid background. Histiocytelike (synovial) cells were seen lying in all cases and as pseudopapillary structures in two.

CONCLUSION

The presence of a cyst at a classic location with aspiration of gelatinous material and the presence of singly occurring histiocytelike cells in a mucoid background in smears is diagnostic of bursal cyst. The procedure is therapeutic in some cases.