Referred Pain in Right Arm from Abdominal Wall Pseudoaneurysm
A 48-year-old male patient (height 165 cm, weight 76 kg) visited our clinic with abdominal pain on the right upper abdomen. The patient had exploratory laparotomy for abdominal abscess 25 years ago, but there was no acute complication from the operation. However, the patient has felt localized pain and allodynia around the surgical scar since 4 years ago. The pain nature was continuous, throbbing, and pulsatile, and the pain was aggravated by overwork or alcohol consumption; relieved by compression of the scar. On rest, the pain was 4 out of 10 and when aggravated, went as high as 8 out of 10 on 11-points numeric rating scale. Whenever aggravated, the pain had radiated to his right upper arm once every 2-3 seconds. The nature and intensity of radiating pain was similar with the original pain. The pain has accompanied by heated sensation of the abdomen and right upper arm.\nThe patient had been taking aspirin and hypoglycemic medications for diabetes mellitus. However, his pain was regarded as different with diabetic truncal neuropathy that causes burning pain or dysthesias with multi-dermatomal distributions. Before visiting our clinic, he had taken CT scanning of abdomen twice and MRI of cervical spine and received conservative treatments, including oral analgesics (i.e. acetaminophen, tramadol, opioids), ketamine infusion therapy, intercostal nerve blocks, pulsed radiofrequency therapy of thoracic dorsal root ganglia in several other hospitals for 18 months. Abdominal CTs and cervical MRI did not show any abnormal conditions and his pain was not only alleviated temporarily, but he also suffered from drug adverse effects, including hepatitis and light-headedness.\nPhysical examination revealed 3 cm long surgical scar on the right upper abdomen and focal tenderness, allodynia and hyperesthesia around the scar. Contrastively, there were no abnormal findings in the right upper arm. Subsequently, gray-scale ultrasonography coupled with color Doppler flow imaging was performed to find any soft tissue lesion, such as inflammation and neuroma.\nColor Doppler US showed a vascular mass with turbulent blood flow, which was a 0.62×0.27×0.69 cm sized mass in the subcutaneous layer of the mid-surgical scar (). The lesion was suspected to be a symptomatic pseudoaneurysm originating from an artery or possibly an arteriovenous fistula, while there was no demonstrable entering or exiting vessel. So, the patient was transferred to a vascular surgeon for treatment of it.\nSclerotherapy was decided for pseudoaneurysm under US guidance. Skin was punctured by medicut under US guidance and the mass was enhanced using contrast media under fluoroscopy (). A mixed material (glue:lipidol = 1:2) was used for embolization of pseudoaneurysm. The day after the procedure, US showed that a mixture of glue and lipidol had filled the pseudoaneurysm with posterior acoustic shadow. Patient was discharged with substantially diminished tenderness. Two weeks later, his symptoms, including referred pain to the right upper arm, were completely subsided without any medications.