great vessel injury is a rare but fatal complication that can occur during lumbar disc surgery .
great vessel injury can result in massive retroperitoneal hemorrhage or present as a delayed pseudoaneurysm or arteriovenous fistula ( avf)2,3,6,8,9,11 ) . despite a very low incidence ( 0.016 - 0.17% ) ,
the reported mortality rate ranges from 15% to 100% , and this complication may elicit serious medicolegal problems2,4,5,7,9,10,12 ) . in cases of great vessel injury , early detection and management is critical to ensure patient survival1,4,7 ) .
major vascular surgery is often required to prevent fatality ; however , procedure - related morbidity and mortality must also be considered4,5,10 ) .
we describe the case of a woman who sustained a common iliac artery and vein injury after l4 - 5 lumbar microdiscectomy .
a 48-year - old woman referred to hospital for radiating pain in her lower back and right leg .
magnetic resonance imaging of the lumbar spine showed a ruptured disc in l4 - 5 .
patient vital signs were stable during the operation and immediate postoperative period , and the radiating pain disappeared with no evidence of neurological deficit .
although no symptoms such as abdominal cramps were noted , the postoperative hemoglobin level decreased from 13.5 g / dl initially to 8.6mg / dl postoperatively .
1 ) . with the suspicion of postoperative hemorrhage , emergent abdominal ultrasonography and computed tomography ( ct ) were performed .
imaging studies revealed a large retroperitoneal hematoma and a pseudoaneurysm near the right common iliac artery and right common iliac vein ( fig .
vital signs were monitored , with blood pressure at 110/70 mmhg and heart rate at 70 beats / min . while vital signs were stable , an endovascular intervention was planned .
aortography demonstrated a traumatic avf between the right common iliac artery and the right common iliac vein with a 1cm - sized pseudoaneurysm ( fig .
seoul , korea ) and a 94 cm - sized balloon at the right common iliac artery ( fig .
no retroperitoneal hemorrhage was identified on the 3-month follow - up ct scan ( fig .
the patient was given a 1-year supply of clopidogrel , and was stable and asymptomatic 3 years after the surgery .
major vessel injury is a rare but well - known complication in lumbar disc surgery . despite advances in modern microscopic surgical techniques and laser - assisted surgery ,
since many cases remain undetected or are not reported , the true incidence of major vessel injury may be higher than what is reported in the literature .
the common iliac artery and common iliac vein are located anterior to the l4-l5 lumbar and l1 sacral vertebral bodies , which is where great vessel injury most frequently occurs1,4 ) .
great vessel injury is the most frequent injury that occurs when operating on the l4 - 5 lumbar segments6,9 ) .
the injury is caused by the perforation of the anterior spinal ligament while attempting complete removal of disc material using a rongeur .
the common iliac vessels and the disc are usually separated by the anterior spinal ligament alone at the lower lumbar spinal level .
disc degeneration may weaken this ligament and alter the relationship between the ligament and the adjacent vascular structures2,3 ) .
the clinical course of vascular injuries can vary and can be categorized into acute , subacute , and chronic .
acute blood loss may occur due to damage caused by a severe arterial laceration and lead to sudden hypovolemia10 - 12 ) .
diagnosis of avfs or pseudoaneurysms can be delayed because of unusual clinical symptoms and a lack of specific warning signs .
vessel injuries may be detected quickly , especially in cases of profuse arterial bleeding and hypotension with tachycardia . however , as in the present case , bleeding may be minimal or go undetected in half of the injuries6,7 ) .
even when massive hemorrhage occurs , blood usually collects in the retroperitoneal space , and blood pooling in the disc space may not be recognized in the surgical field .
moreover , the prone position in which the patients are operated may confer a degree of vascular compression during surgery , and as such , this may temporarily tamponade any vascular tears7,9 ) .
surgeons should suspect vessel injury if hemorrhage or fat tissue is observed during a lumbar discectomy even when vital signs are stable . after a vessel injury , the duration of detection and the treatment approach
are associated with the mortality rate1,2,5,7,12 ) . when the vessel injury is recognized intraoperatively and signs of life - threatening hypovolemic shock are observed , vigorous volume replacement and urgent repair of vascular laceration should be considered . in arterial injuries with critical bleeding ,
although the injury is not confirmed during surgery and the vital signs are stable , insignificant symptoms such as abdominal distension , pain , palpitation , unexplainable anemia , and blurring of the psoas muscle on radiographs are possible predictors of vessel laceration . abdominal ultrasonography and ct angiography are the preferred methods of diagnosis in confirming vessel injury and retroperitoneal hematoma11,12 ) . when diagnosed , conventional angiography and interventional procedure should be performed . in the past
, vascular injury following a lumbar discectomy was treated by direct surgical repair of the damaged vessels9,10 ) .
although the current outcomes are considered good , surgical repair of traumatic or postoperative vascular injury may result in considerable blood loss and complications4,10 ) .
endovascular techniques are an alternative method of managing the vascular injury following lumbar disc surgery .
endovascular techniques using a stent graft to occlude avf or leakage show satisfactory bleeding control with few complications1,4,7,10,11 ) .
the advantages of these procedures are the absence of a lower abdominal incision , minimal blood loss , and reduced depth and length of anesthesia , which consequently allows for shorter hospitalization periods compared with conventional surgery .
however , proper facilities and preparation of stent grafts and other materials are mandated for endovascular intervention7 ) . delayed onset of symptoms or signs may occur in patients who undergo lumbar disc surgery because of an avf or pseudoaneurysm2,8,11 ) .
swelling of the legs , fatigue , shortness of breath , cardiac failure , classic machinery bruit in the abdomen , and delayed bleeding may lead to the diagnosis of avf6,8 ) .
most isolated vascular injuries of the great retroperitoneal veins remain clinically silent because of a tamponade effect of a perivascular hematoma1 ) .
therefore , the treatment of stable avfs or pseudoneurysms should not be delayed , and only arterial side sealing would be sufficient , as in the present case .
vascular injury following lumbar disc surgery necessitates early recognition , diagnosis , and prompt surgical repair for prevention of fatal outcomes .
an endovascular repair using a stent graft is a minimally invasive and efficient treatment modality with low morbidity .
 great vessel injury is a rare but well - known complication of lumbar disc surgery , which may result in acute or fatal outcomes of delayed diagnosis . 
 thus , early detection and proper management is vital . 
 the authors report a case of retroperitoneal hemorrhage with arteriovenous fistula and pseudoaneurysm after lumbar microdiscectomy . 
 the patient was successfully managed by endovascular intervention using a stent graft . 
 endovascular repair is a minimally invasive and efficient treatment modality with considerably low morbidity and mortality . 
INTRODUCTION
CASE REPORT
DISCUSSION
CONCLUSION