Late Treatment Failure after Stenting and Percutaneous Aspiration for Adventitial Cystic Disease in the Popliteal Artery: A Follow-up Case Report

Abstract

Adventitial cystic disease (ACD), a rare vascular disease characterized by mucus accumulation in the adventitia of blood vessels, typically affects the popliteal artery. We present the case of a 61-year-old female diagnosed with ACD in 2018 who was initially treated with endovascular stenting and percutaneous aspiration of the cyst. The patient, who had been asymptomatic for 5 years, developed a stent fracture and pseudoaneurysm requiring surgical intervention. Despite initial successful treatment, complications such as stent fracture and recurrence can occur; therefore, surgical treatment is recommended to optimize outcomes in patients with ACD. Endovascular treatment and cyst aspiration should only be considered in cases with high surgical risk. After treatment, long-term follow-up and individualized management strategies are important to monitor ACD recurrence.

INTRODUCTION

Adventitial cystic disease (ACD) is a rare vascular disease characterized by accumulation of mucinous substances within the adventitia of blood vessels. It most commonly affects the popliteal artery (PA), with patients typically presenting with symptoms of claudication. Treatment options for ACD include conservative management, surgical intervention, percutaneous aspiration, and percutaneous endovascular procedures [1]. Percutaneous treatments offer advantages such as faster recovery and fewer anesthesia-related side effects [2]. Although percutaneous procedures have a higher recurrence rate than surgical treatments, these have been attempted in several cases.

Woo et al. [3] previously reported a case of ACD, successfully treated with endovascular stenting and percutaneous needle aspiration. However, after six years, the patient developed a stent fracture and pseudoaneurysm, requiring excision and an interposition graft. Although disappointing, we share these long-term results and recommend against stenting in ACD. This case report was approved by the Institutional Review Board (IRB) of the Seoul National University Hospital (IRB No. 2102-107-1197), and the patient provided consent.

CASE

A 61-year-old female was diagnosed with ACD in 2018. The patient initially presented with right calf claudication, and computed tomography angiography (CTA) confirmed segmental occlusion of the distal superficial femoral artery (SFA) and proximal PA. A 6 mm×8 cm drug-eluting stent (Eluvia, Boston Scientific) was placed in the occluded segment [3]. During a multidisciplinary conference following the procedure, the patient was found to have a cystic lesion compressing the PA. Subsequent percutaneous needle aspiration drained, gelatinous fluid, confirming the diagnosis of ACD. Her claudication symptoms had resolved and ankle brachial index (ABI) improved at an outpatient visit 3 months after discharge. The patient was followed-up annually using duplex ultrasonography (DUS). The claudication symptoms did not recur for 5 years.

In January 2024, she experienced brief pain in her right posterior knee during exercise, though the pain subsided shortly after. The patient visited a nearby hospital and underwent a CT scan, which showed a fractured stent with pseudoaneurysm that ruptured into a recurrent or remnant adventitial cyst at the right PA (Fig. 1). The ABI was measured as 1.14/1.24.

Fig. 1.

Pre-operative computed tomography scan: Stent fracture (arrow) with pseudoaneurysm ruptured into adventitial cyst. (A) Axial image. (B) Coronal image.

Surgical intervention was performed using a medial approach. The distal SFA and PA were exposed through an above-knee longitudinal incision. The procedure involved excision of the aneurysmal PA, including the fractured stent, followed by an interposition graft using a reversed great saphenous vein (Fig. 2, 3). No connection between the PA and knee joint was identified. The recovery was uneventful, and the patient was discharged on the 5th postoperative day.

Fig. 2.

Intraoperative photographs. (A) Dissected right distal SFA-P2 PA. (B) Harvested right GSV from the distal thigh, 10 cm. (C) Anastomotic reconstruction of the PA using an autogenous GSV graft. SFA, superficial femoral artery; PA, popliteal artery; GSV, great saphenous vein.

Fig. 3.

Excised distal superficial femoral artery to popliteal artery including fractured stent inside.

One week after discharge, the patient visited the emergency room with mild edema and pain in her right leg. CT revealed a large cystic structure in the intermuscular plane along the sartorius muscle, and ultrasonography-guided aspiration was safely performed (Fig. 4). The patient remains in good condition on regular follow-ups, and has been prescribed cilostazol.

Fig. 4.

Postoperative computed tomography scan performed in emergency room. (A) Cystic structure along the sartorius muscle (arrow). (B) Sono-guided aspiration was performed. (C) Three-dimensional volume rendering image showing a patent reversed autologous great saphenous vein graft without leak and good distal runoff.

DISCUSSION

Adventitial cystic disease is a rare but clinically significant vascular condition that primarily affects the arteries, particularly the PA. It may also involve other peripheral arteries and veins [1].

The etiology of ACD remains unclear, and “synovial theory” is currently considered the most plausible of the several hypotheses proposed to explain its pathogenesis [4]. This theory is based on the confirmed connection between the cyst and synovial structure of the joint in ACD cases. Consequently, it necessitates performing disconnections through ligation of the articular branch during surgery. In addition, the “developmental theory” postulates that mucin-secreting cells are integrated into the arterial adventitia during fetal development. The “repetitive trauma theory” suggests that repetitive trauma or microscopic damage to the artery causes local inflammation, resulting in cyst formation. The “degenerative theory” suggests that it is caused by degeneration of connective tissue [4].

Patients with ACD typically present with intermittent claudication or ischemic symptoms, which must be distinguished from atherosclerosis. A reduced ABI is observed, but systemic cardiovascular risk factors are usually absent. Additionally, ACD primarily affects young and middle-aged individuals, contrasting with the older population commonly affected by atherosclerosis.

The imaging techniques for the differential diagnosis of ACD include DUS, CT, or magnetic resonance imaging (MRI). DUS is a noninvasive test that can be employed for initial assessment [5,6]. ACD can be distinguished from an aneurysm by the the presence of vascular flow within the cyst and posterior acoustic enhancement on ultrasonography. CT and MRI are useful for further differentiation. CT can identify a cyst that compresses the artery without invading the fat plane [7]. By providing information on the anatomic structure around the cyst, the exact location of the cyst and the resulting vascular lesions can be confirmed. MRI is an effective method for distinguishing cystic and solid lesions. Furthermore, MRI has the advantage of delineating the relationship between the cyst and surrounding structures, including the vessel wall and any connection with the joint space, which is critical for surgical planning [4].

In this case, the CT scan clearly showed a stent fracture that perforated into the adventitia, resulting in blood leakage into the recurrent or remnant adventitial cyst. Although MRI was not performed, it could have been beneficial for identifying the cystic lesions and potential joint connections.

Due to the rarity of ACD, various treatment methods have been proposed. Surgical treatment remains the gold standard therapy for addressing the underlying cause of arterial compression and preventing ischemic progression [8,9]. Depending on the location and extent of the cyst, various surgical options can be considered, including cyst excision alone and arterial excision with an interposition graft [6,8,10]. In addition to surgical treatment, percutaneous aspiration and endovascular techniques can also be used. DUS- or fluoroscopy-guided aspiration has the advantage of being less invasive with a shorter recovery time, but it is associated with a high recurrence rate [11]. Endovascular techniques, including angioplasty or stent insertion, can be considered in cases where cyst compression is not severe [3,12]. However, the risk of complications, such as in-stent restenosis, stent fracture, and disease recurrence, remains [13].

As shown in this case, surgical resection followed by an interposition graft are the definitive treatment [9,14]. Recurrence or treatment failure after endovascular treatment usually occurs within 5 months, as reported in previous cases [3,12]. The PA is prone to various stresses and causes frequent stent fractures; hence, stenting in PA is generally not recommended. Endovascular stenting and cyst aspiration for ACD should be deferred and considered in limited cases with a high surgical risk. Continuous follow-up is essential to ensure sustained arterial patency and to promptly address any recurrence, ultimately improving patient outcomes.

Funding Statement

FUNDING None.