Iatrogenic brachial artery pseudoaneurysm causing median nerve compression neuropraxia diagnosed and compression therapy ultrasonography: A rarest case image

A 69-year-old male with a known history (Hx) of chronic kidney disease (CKD) was presented with a 2-day Hx of inability to flex the proximal and distal interphalangeal (DIP) joints of the first, second, and third digits of his left hand. Notably, he retained the ability to flex the proximal and DIP joints of the fourth and fifth fingers. This presentation followed balloon fistuloplasty (BF) performed to address stenosis of an arteriovenous fistula between the radial artery and cephalic vein.

Physical examination revealed swelling and erythema on the ventral aspect of left upper arm. He was referred for ultrasonography (USG) for the same.

Ultrasound imaging of the left upper arm was conducted. The examination revealed a well-defined cystic lesion measuring 27 × 7 × 10 mm, originating from the wall of the brachial artery. Doppler study demonstrated a “ying yang” sign on color Doppler, indicative of a pseudoaneurysm (PNA). Notably, the PNA was observed to pulsate against the median nerve (MN), leading to neuropraxia (Figure 1).

Under ultrasound guidance, compression therapy for 15 min was performed and complete obliteration of lumen was achieved and was confirmed on Doppler study showing no flow in the lumen of PNA (Figure 2).

The MN descends down the arm, initially lateral to the brachial artery. Halfway down the arm, the nerve crosses over the brachial artery and becomes situated medially [1]. The MN is formed from all anterior rami of C5-T1 [2]. It predominantly provides motor innervation to the flexor muscles of the forearm and hand and also provides sensory innervation to the dorsal aspect (nail bed) of the distal first two digits of the hand, the palmar aspect of the thumb, index, middle, and half of the ring finger, the palm, as well as the medial aspect of the forearm [3].

MN neuropraxia associated with post iatrogenic vascular injury to the brachial artery is very low and is a degraded complication. Brachial PNA could result in compression of the MN in the arm leading to an ischemic injury [4]. In this case, the patient was presented with pain and erythema of the left upper arm. From the given Hx, the patient was a known case of CKD and was undergoing hemodialysis for the same. A fistula between the radial artery and cephalic vein was created. Later, after 5 months of arterio-venous fistula, he developed features of arterio-venous fistula stenosis, and BF was advised for the same.

In this patient, a complication of arterio-venous stenosis was diagnosed. USG and color Doppler of the upper arm at the incision site showed a PNA, which was seen pulsating and compressing the MN. Thus, a diagnosis of neuropraxia was made. Compression therapy for 15 min was performed, and complete occlusion of the PNA was obtained.

Our case underscores the significance of prompt recognition and management of PNAs following vascular interventions. Utilization of high-resolution USG enables accurate diagnosis and facilitates targeted interventions such as compression therapy. Early intervention is essential to prevent potential neurological complications and optimize patient outcomes.

Dr. Alamgir Khan analyzed the data and prepared the first draft of the manuscript. Dr. Arjun Ganpat Munde participated in the conception and design of the study, Dr. Alamgir Khan constructively revised the manuscript; Dr. Thamizh Selvan participated in data collection and organization; Dr. Manohar Kachare participated in and supervised the study throughout, and they share corresponding authorship. All authors commented on previous versions of the manuscript and approved the final version.

The author(s) declare(s) no conflict of interest.

Not applicable.

The patient provided written informed consent at the time of entering this study.