Prevalence of various congenital vascular malformations in patients with Klippel-Trenaunay syndrome.

OBJECTIVE: Klippel-Trenaunay syndrome (KTS) is a condition defined by the association of three physical features: capillary malformation, varicosities, and hypertrophy of bony and soft tissues. However, KTS is characterized by congenital vascular malformations (CVMs) that are difficult to classify. Therefore, the present study was undertaken to analyze the various CVMs in patients with KTS.

METHODS: Sixty-one patients with KTS were enrolled, and their CVMs were divided into predominantly venous defects, predominantly lymphatic defects, and mixed vascular defects using the Hamburg Classification. Capillary malformations were subdivided into port-wine stain, telangiectasia, and angiokeratoma. Truncular and extratruncular vascular malformations were detected using duplex ultrasound and magnetic resonance imaging. Reflux in the superficial and deep venous systems was also evaluated.

RESULTS: Forty-five patients (74%) had predominantly venous defects, four (6%) had predominantly lymphatic defects, and 12 (20%) had mixed vascular defects. Capillary malformations were detected in 54 patients (89%), among which port-wine stain was the most predominant (40 patients, 66%), followed by telangiectasia (31 patients, 51%) and angiokeratoma (18 patients, 30%). Extratruncular venous malformations were detected in 47 patients (77%). In contrast, truncular venous malformations were found in 50 patients (82%). Among these, embryonic lateral marginal vein showed the highest occurrence, accounting for 53% (32 patients). However, reflux in this vein was detected in only nine patients (15%). Twelve patients (20%) had reflux in the great saphenous vein, and four (7%) had reflux in the small saphenous vein. Deep vein hypoplasia was found in seven patients (12%), and only five patients (8%) had deep vein aplasia. Extratruncular lymphatic malformations were found in 13 patients (21%) and truncular lymphatic malformations in 17 (28%).

CONCLUSIONS: Patients with KTS have a variety of CVMs, but both extratruncular and truncular venous malformations continue to be targets for intervention.