Two Cases of Micro-Arteriovenous Fistula in the Lower Extremity with Misdiagnosis of Refractory Cellulitis

A Case of Cerebral Arteriovenous Malformation and Malformation of the Lower Limbs

The case involves a 37-year-old female who was diagnosed with undifferentiated immunodeficiency and protein-losing gastroenteropathy at the age of 26 and was under outpatient care in the gastroenterology department while taking Prednisolone 15mg. At the age of 37, she experienced loss of consciousness and was diagnosed with a right occipital lobe arteriovenous malformation upon investigation. Although initially managed conservatively, she presented the following month with a right-sided headache and vomiting and was urgently transported to our hospital. Imaging with contrast-enhanced CT revealed bleeding from the arteriovenous malformation. Emergency craniotomy was performed, followed by ventricular drainage. Two weeks later, she underwent transcatheter arterial embolization of the main feeder via the right femoral artery approach, followed by excision of the arteriovenous malformation the next day. Subsequently, she had an uneventful recovery. A confirmation CT angiography before discharge revealed severe stenosis of the right common femoral artery, leading to a referral to the cardiovascular surgery department. The stenosis was attributed to the Pro-Glide used for hemostasis during the embolization procedure. Repair surgery was performed, during which CT angiography revealed arteriovenous malformations in both the popliteal fossae and the foot.

Cyanoacrylate closure for arteriovenous fistula in the lower extremity with saphenous vein insufficiency

A lower extremity arteriovenous fistula (AVF) is sometimes associated with venous disease following venous hypertension, especially when the saphenous vein is the main return route. This can cause venous dilation, leading to valve insufficiency. A complete cure can be difficult in cases with multiple vascular branches. We report three surgical cases of lower extremity AVF with saphenous vein insufficiency. All patients had saphenous vein insufficiency with long duration leg symptoms and underwent full-length occlusion of saphenous vein using cyanoacrylate closure. Substantial improvements in leg symptoms and appearance were observed immediately after surgery in all three patients. Cyanoacrylate closure could be a treatment option for lower extremity AVF.

Micro-arteriovenous fistula in patients with lower limb lymphedema

BACKGROUND

A micro-arteriovenous fistula (AVF) is a minute, short shunt between an artery and a vein that does not pass through a capillary. We investigated the association between micro-AVFs and lymphedema using computed tomography angiography (CTA) and venous blood gas analysis.

METHODS

In 95 patients with lower limb lymphedema, the presence or absence of early venous return (EVR) was compared between patients with primary and secondary lymphedema. Furthermore, we investigated the difference in the timing of edema onset in patients with secondary lymphedema with or without EVR using CTA. In 20 patients with lower limb lymphedema with confirmed early EVR in a unilateral lower limb, the partial pressure of oxygen (PO2) was compared between the lower limb with EVR and the contralateral lower limb.

RESULTS

Secondary lymphedema with or without EVR occurred at an average of 36.0±59.3 months and 93.5±136.1 months, respectively; however, no significant difference was noted. PO2 was 57.6±11.7 mmHg and 44.1±16.4 mmHg in the EVR and non-EVR limbs, respectively, which was a significant difference (P=0.005).

CONCLUSIONS

EVR and venous blood gas analysis suggested the presence of micro-AVFs in patients with lower extremity edema. Further research is warranted to examine the cause of micro-AVFs, to advance technology to facilitate the confirmation of micro-AVFs by angiography, and to improve lymphedema by ligation of micro-AVFs.

Abnormalities of the hallux skin and nail in the course of very rare arteriovenous malformation

Arteriovenous malformations (AVMs) are usually found in the pelvic area and the brain. These vascular anomalies are rarely reported in the toes. AVMs in the toes may be asymptomatic, but can also cause atypical symptoms. Congenital AVMs can expand as patients age and manifest in adulthood. They may be provoked by injury. Acquired AVM might be caused by iatrogenic factors, venous or arterial catheterization, percutaneous invasive vascular procedures, surgery, or degenerative vascular disorders. An AVM can damage surrounding tissues and can cause destruction of skin, nails and bones. The course of the disease is often unpredictable and diagnosis is usually delayed as a result.

A Novel Surgical Approach for Refractory Secondary Lymphedema of the Lower Extremity Accompanying Micro-Arteriovenous Fistula

Lymphaticovenous anastomosis (LVA) for lymphedema of the lower extremity has been established as a minimally invasive and effective surgical treatment to return static lymph fluid to the vein. However, we often experience cases in which the effect of LVA cannot be obtained sufficiently, or the anastomotic site becomes obstructed and the edema deteriorates over a long term. One of the causes is the combination of local venous hypertension (VT) by micro-arteriovenous fistula (mAVF). We report two cases of refractory lymphedema at the lower extremity caused by mAVF and incompetent perforating vein (IPV). In these cases, surgical ligation and separation of the mAVF and IPV is effective in reducing edema.