case_images: PMC10233604_01
case_images: Grayscale ultrasound (US) at the left antecubital fossa in transverse and
  longitudinal views reveals a 1.6 x 0.5 x 0.3 cm serpentine, avascular,
  hypoechoic collection (yellow calipers) deep to the cephalic vein, which
  represents a small hematoma.
case_images: 10.1177_11795476231177793-fig1.jpg
case_images: PMC10233604_01_10.1177_11795476231177793-fig1.jpg
case_images: fig1-11795476231177793
case_images: Given concerns for possible underlying pseudoaneurysm, aneurysm, hematoma or fistula, a venous ultrasound performed in the radiology department, identified a 1.7 x 0.3 x 0.5 cm hematoma in the antecubital fossa posterior to the cephalic vein (Figure 1), as well as pulsatile flow and an arterialized waveform in the left cephalic vein (Figure 2).
case_images: Longitudinal Color and spectral Doppler US at the left antecubital fossa
  reveals a pulsatile, arterialized waveform in the cephalic vein, concerning
  for an arteriovenous fistula.
case_images: 10.1177_11795476231177793-fig2.jpg
case_images: PMC10233604_01_10.1177_11795476231177793-fig2.jpg
case_images: fig2-11795476231177793
case_images: Given concerns for possible underlying pseudoaneurysm, aneurysm, hematoma or fistula, a venous ultrasound performed in the radiology department, identified a 1.7 x 0.3 x 0.5 cm hematoma in the antecubital fossa posterior to the cephalic vein (Figure 1), as well as pulsatile flow and an arterialized waveform in the left cephalic vein (Figure 2).
case_images: Transverse Color Doppler US the left antecubital fossa reveals a small
  tortuous arterial branch (white arrow) joining the cephalic vein (yellow
  arrow) confirming arteriovenous fistula as cause for the pulsatile waveform
  in Figure 2.
case_images: 10.1177_11795476231177793-fig3.jpg
case_images: PMC10233604_01_10.1177_11795476231177793-fig3.jpg
case_images: fig3-11795476231177793
case_images: An abnormal connection between a small arterial branch and the cephalic vein was visualized, consistent with an arteriovenous fistula (Figures 3 and 4).
case_images: Longitudinal microvascular flow US at the left antecubital fossa confirms the
  abnormal connection between a small arterial branch and the cephalic vein
  (white arrow). This technique improves visualization of blood flow in small
  structures such as superficial arterial and venous branches.
case_images: 10.1177_11795476231177793-fig4.jpg
case_images: PMC10233604_01_10.1177_11795476231177793-fig4.jpg
case_images: fig4-11795476231177793
case_images: An abnormal connection between a small arterial branch and the cephalic vein was visualized, consistent with an arteriovenous fistula (Figures 3 and 4).