JAOCR at the Viewbox: Parkes Weber Syndrome

Parkes Weber Syndrome

A 10-year-old girl with no significant prior medical history was referred from her pediatrician to the interventional radiology clinic for persistent right lower extremity swelling and enlarging veins predominantly about her right shin. Ultrasound demonstrated multiple enlarged superficial veins (A) with arterialized waveforms, which was initially reported as a traumatic AV fistula.

A more thorough physical examination demonstrated two small 2- to 3-cm flat reddish-purple lesions on the patient’s right posterior upper thigh and gluteal fold as well as a subtle 3-cm limb-length discrepancy. Mild right leg hypertrophy was initially thought to be secondary to swelling by the pediatrician, but likely represents limb overgrowth.

MRI of the right lower extremities was performed demonstrating the extent of disease, particularly with the time-resolved MRA sequence (TWIST) (B), which gives an overview of the numerous arteriovenous fistulous communications with capillary components (green arrow) and early draining embryonic sciatic vein (blue arrow). Coronal STIR sequence (C) showed mild leg-length discrepancy and part of the capillary malformation component in the lower leg (red arrow). The patient indicated persistent pain in her right shin and was taken to the interventional suite for further evaluation and possible embolization of the arteriovenous fistula.

Antegrade access was obtained through the right common femoral artery and angiography of the anterior tibial artery (D, E) was performed showing innumerable arteriovenous communications predominantly about the knee and shin, confirming suspicion for Parkes Weber syndrome (PWS).

Arteriovenous malformation at the symptomatic focus of pain was subsequently embolized (F) with coils from an arterial approach (red arrow) and n-Butyl cyanoacrylate glue (blue arrow) from a retrograde approach by direct puncture through the symptomatic superficial vein. The patient’s local symptoms improved postoperatively.

PWS is a rare vascular anomaly that results in numerous abnormal vessels within the affected region and can clinically present with usually regional small capillary malformations on the face or limb in addition to overgrowth of the affected region/limb.¹ PWS is distinguished from Klippel-Trenaunay syndrome with presence of arteriovenous fistulas. Relatively recent association of PWS with RASA1 genetic mutation^2,3 has opened a pathway for promising pharmacologic approaches to therapy. Nonetheless, at this time, overall progression of disease is expected and endovascular therapy of complex arteriovenous fistulas is predominantly focused on symptomatic relief of focal pain, bleeding or ulceration.

References

1. Kumar V, Jorwal P, Biswas A, Deorari V. Parkes Weber syndrome. QJM 2019;112(12):936.
2. Monroe EJ. Brief description of ISSVA classification for radiologists. Tech Vasc Interv Radiol 2019;22(4):100628.
3. Boccara O, Eyries M, Pannier S, Ariche-Maman S, Hadj-Rabia S, Coulet F. Parkes-Weber syndrome related to RASA1 mosaic mutation. Clin Genet 2021;99(2):330-331.