Congenital Vascular Malformations: General Diagnostic Principles

Venous malformation (VM) is the most common congenital vascular malformation (CVM), which usually presents as a single lesion in the majority of cases. It also presents as a mixed lesion combined with other CVMs (e.g. lymphatic malformation and arteriovenous malformation [AVM]). Therefore, the diagnosis of VM should include an appropriate work-up, to not only confirm and characterize the VM as either extratruncular or truncular but also to diagnose or exclude the presence of other CVMs. The diagnosis of VM can be made safely using non-invasive to minimally invasive studies, which can also distinguish VM from infantile haemangioma. Invasive studies, such as venography and arteriography, are generally reserved for therapeutic planning and diagnosis of more virulent CVMs (e.g. AVM). The work-up of VM should include a complete assessment of the extent and severity of the primary VM lesion. In addition, its embryologic origin, as well as its haemodynamic characteristics and secondary effects should also be determined.

Venous malformation and haemangioma: differential diagnosis, diagnosis, natural history and consequences

Venous malformation (VM) is the most common form of congenital vascular malformation (CVM). VM presents at birth as an inborn vascular defect and never disappears/regresses spontaneously through the rest of life; it will continue to grow slowly at a rate that is proportional to the growth rate of the body. Haemangioma is not a vascular malformation but one of the vascular tumours originating from the endothelial cells; it develops after birth mostly in the infantile/neonatal period with a distinctive growth cycle: a proliferation phase of early rapid growth followed by an involutional phase of slow regression. Although the vascular malformation and vascular tumour belong to the ‘vascular anomaly’ together, both conditions are fundamentally different not only in their anatomical, histological and pathophysiological findings but also in their clinical courses. Therefore, an appropriate differential diagnosis of the VM is mandated not only from other kinds of CVMs but also from ‘genuine’ haemangioma. Appropriate diagnosis and assessment of VMs can be made based on clinical presentation and a proper combination of basic non-invasive studies in general but the presence of a mixed lesion involving other types of CVM lesions and the type of VM lesion, extratruncular and truncular, will dictate the need for further work-up with additional non- to less-invasive study or angiography. Otherwise, angiography is usually reserved for therapeutic planning and treatment.

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.

Reconstructive surgery for chronic lymphedema: a viable option, but

The aim of the paper is to assess the efficacy of reconstructive lymphatic surgery in the treatment of chronic lymphedema via retrospective analysis. Lymphovenous anastomotic surgery (LVAS) or free lymph node transplant surgery (FLTS) was performed on 32 patients who failed to respond to complex decongestive therapy (CDT) alone for a minimum of a one-year period. In LVAS, three patients with good compliance among 19 were able to maintain initial improvement through the four-year follow-up period. All three had secondary lymphedema in clinical stage II. In FLTS, among 13 patients, three compliant patients with the secondary lymphedema in clinical stage II kept initial improvement through the four-year follow-up. In conclusion, reconstructive lymphatic surgery (LVAS and FLTS) appears to be more effective in secondary lymphedema versus primary lymphedema when performed in the early stages. Patient compliance to maintain CDT postoperatively remains the most critical factor in maintaining durable long-term results. FLTS seems to have an additional risk involved to the donor lymph node harvest and a limited role compared to LVAS. Further extended study on FLTS is required to demonstrate its efficacy compared with LVAS.

Primary lymphoedema and lymphatic malformation: are they the two sides of the same coin?

OBJECTIVES

To clear the confusion regarding the relationship between the 'primary lymphoedema' and (truncular) lymphatic malformation (LM); the latter is one of congenital vascular malformations.

MATERIALS & METHODS

A literature review was carried out on the primary lymphoedema either existing as an independent LM lesion or as a component of the Klippel-Trenaunay syndrome.

RESULTS

The review was able to provide a contemporary guide/conclusion on the definition and classification, clinical evaluation and clinical management regarding conservative (physical) therapy, reconstructive surgical therapy and ablative/excisional surgical therapy, for the primary lymphoedema as an LM.

CONCLUSIONS

Primary lymphoedema can be considered as 'congenital' since its majority represents a clinical manifestation of the truncular type of LM arising during the later stages of lymphangiogenesis. Such embryological staging information of the LM is critical for proper management of the primary lymphoedema when it exists with other congenital vascular malformations (Klippel-Trenaunay syndrome). 2. Basic non-invasive to minimally invasive tests will provide an adequate diagnosis and lead to the correct multidisciplinary, specifically targeted and sequenced treatment strategy. 3. The mainstay of current management of the primary lymphoedema/truncular LM is complex decongestive therapy; and the reconstructive as well as ablative surgical therapy remain adjunctive therapies at best.

Arterio-venous malformation: how much do we know?

Arterio-venous malformation (AVM) is a congenital vascular malformation that is neither a venous malformation nor a haemangioma. An AVM is a potentially life-threatening and limb-threatening lesion, especially the 'fistulous' truncular form due to its unique embryological and haemodynamic characteristics. AVM treatment requires an early aggressive approach, one that is careful and based on a thorough assessment of the risks and benefits associated with the treatment plan. A successful treatment strategy requires an accurate assessment of the AVM taking into account the extent, severity and progression of the lesion. This is critical in order to minimize the morbidity associated with the currently available therapies. A multidisiciplinary approach that integrates endovascular and surgical therapy can substantially improve the treatment results seen in patients with AVMs. Preliminary treatment of a fistulous AVM with coil embolization is essential in order to minimize associated morbidity and to alter the lesion haemodynamics from a high-flow lesion to a low-flow lesion that is more amenable to subsequent, definitive management with ethanol or NBCA glue embolo/sclerotherapy.