neurofibromatosis-1 ( nf-1 ) is an autosomal dominant disorder with an incidence of almost 1 in 3000 ; overall , 50% of patients have a family history consistent with this disorder .
the major features include multiple neural tumors ( neurofibromas ) , numerous pigmented skin lesions ( which may include caf au lait spots ) , and pigmented hamartomas affecting the iris ( lisch nodules ) .
approximately , 95% of these patients will develop cutaneous or subcutaneous neurofibromas , and 30% will develop plexiform neurofibromas .
the 12x magnification afforded by the laparoscope appeared to facilitate the careful dissection around the nerves .
recently , the da vinci surgical robot has entered the surgical realm , most notably in urology for the surgical treatment of prostate cancer .
the 6 degrees of freedom afforded by the robot instrumentation , combined with the 3d high - definition image , and rock steady operating arms , allow the surgeon to operate in an extremely precise , meticulous manner heretofore unavailable .
in addition , the magnification provided by the endoscope varies from 12x to 40x depending on its proximity to the target tissue .
application of this technology for excision of a neurofibroma has appeared in the literature on only one occasion : in 2003 , a mediastinal neurofibroma was removed by cardiothoracic surgeons using a totally endoscopic approach with three 1-cm incisions for the robotic ports .
herein , we report the first case of a robotic - assisted laparoscopic resection of a thoracolumbar neurofibroma via a retroperitoneoscopic laparoscopic approach , making it the first case of a paraspinal tumor removed robotically .
a 19-year - old male with a history of neurofibromatosis type i presented with a 2-year history of back pain located on the left side of his thoracolumbar paraspinal area with no radiation .
the pain progressively worsened over 2 years increasing significantly the 2 months prior to presentation resulting in the use of narcotic analgesia .
the patient had a past medical history positive for a melanoma , which was excised from his back 3 months before presentation .
family history revealed the patient 's mother has a diagnosis of nf-1 , and a history of multiple tumors including neurofibromas and a melanoma .
physical examination revealed a slender caucasian male ( 59  , 153 pounds ) , with multiple pigmented nevi on his skin .
he had a 3-cm x 3-cm scar in the left mid / upper back area lateral to his spine , where his melanoma had been excised .
the remainder of his physical examination , including a detailed neurological evaluation , was unremarkable .
ct angiography showed a 4.3-cm x 2.9-cm paravertebral mass at the t12-l1 junction , with a slightly widened neural foramen .
the mass appeared adjacent to the upper pole of the kidney , albeit posterior to the inferior left hemidiaphragm .
an mri of the chest revealed a 3.7-cm x 3.0-cm lobulated paraspinal mass at t12-l1 posterior to the upper pole of the left kidney .
mri scan of the thoracic spine with and without contrast revealed the mass to be arising from a widened neural foramen at t12-l1 with no extension into the spinal canal with the mass projecting laterally behind the left kidney and posteriorly into paraspinal muscles .
the mass enhanced uniformly with contrast , consistent with a neurofibroma ( figures 1 , 2 ) .
abdominal ct scan revealing paravertebral mass ( black arrow ) adjacent to the upper pole of the left kidney , posterior to the inferior left hemidiaphragm ( white curve and arrow ) .
spinal angiography revealed the dual supply of the inferior spinal cord by 2 origins of the artery of adamkiewicz , at both t10 and l2 on the left .
both standard open and minimally invasive procedures were discussed . because of the extraspinal retrophrenic / retrorenal location of the mass , a minimally invasive approach was chosen .
urology was consulted regarding the feasibility of accessing the tumor via a retroperitoneal laparoscopic approach and the possibility of using the da vinci robot ( intuitive surgical , sunnyvale , ca ) for tumor excision .
after extensive discussion of the risk and benefits with the patient and his family , the minimally invasive robotic approach was selected with full knowledge of a possible conversion to a standard open approach . with the patient prepared and draped in a right lateral decubitus position , a 12-mm incision was made off of the tip of the twelfth rib .
an ethicon x - cel 12-mm optical port ( ethicon , somerville , nj ) was placed under direct endoscopic control into the pneumoretroperitoneum .
the retroperitoneum was further expanded by using a dissection balloon ( u. s. surgical inc . ,
two 8-mm robotic ports were then placed subcostally , one in the posterior axillary line , and the other in the anterior axillary line ( figure 3 ) .
a 12-mm port was placed above the iliac crest in the anterior axillary line , and a 5-mm port was placed just above and medial to it . docked robot , with 2 working arms , one arm attached to the endoscope , and 2 additional assistant 's ports .
the psoas muscle was identified and dissected medially and superiorly , until the diaphragm was noted .
the kidney , within gerota 's fascia , was mobilized along its posterior surface and retracted medially .
the diaphragm was incised vertically over the mass , and the anterior surface of the mass was dissected until its upper and lower margin could be clearly discerned ( figure 4 ) .
initial view of tumor through robotic endoscope with bipolar serrated graspers in the left robotic hand , monopolar electrosurgical scissors in the right robotic hand , and assistant operated irrigation / suction inferiorly .
the neurosurgeon then sat at the robotic console , while the urologic surgeon assisted at the side of the operating table .
the robotic endoscope ( 12 mm ) and 2 robotic arms ( 8 mm ) were placed through the aforedescribed ports .
bipolar serrated graspers were placed in the left robotic hand , and monopolar electrosurgical scissors were placed in the right robotic hand .
the tumor capsule was coagulated with the bipolar graspers and incised with the activated scissors .
the tumor capsule was extremely thin and friable ; however , the tumor was not soft enough to be removed with suction . in this fashion ,
an intracapsular tumor debulking was accomplished , with the resected tumor pieces removed by the laparoscopic graspers and suction operated by the urologic surgeon . after removing one third of the tumor
, enough space was made to elevate the posterior aspect of the tumor revealing the tumor attachment to its nerve root of origin ( figure 5 ) .
the nerve was coagulated and transected , freeing the remaining , which was placed into an entrapment sack .
fibrin glue was placed over the nerve root to prevent leakage of cerebral spinal fluid .
a small pleurotomy occurred during the tumor resection ; to evacuate the pneumothorax , a 10f cope loop thoracostomy tube was placed percutaneously into the left hemithorax .
the robot was used to close the pleurotomy with a running 40 chromic suture ; the diaphragm was closed using silk suture and lapra - ty clips .
the total operative time was 5.3 hours , of which approximately 2 hours was robotic console time .
the chest tube was removed in the postanesthesia care unit , and repeat chest x - rays confirmed no pneumothorax had developed .
the patient was discharged home on postoperative day 2 ; there were no focal neurological deficits .
while recovering in the hospital , the patient 's pain was controlled with oral morphine cr ( 30 mg ) , given every 8 hours for a total of 7 doses .
he was also given his usual dose of gabapentin ( 200 mg , 3 times a day ) .
at discharge , the patient was given hydrocodone / acetaminophen ( 5/500 ) to be taken orally as needed every 4 hours for pain , and morphine cr ( 30 mg ) to be taken orally as needed every 12 hours for pain for up to 1 week .
pathological examination of the operative specimen showed it to be a neurofibroma , composed of stellate and spindle - shaped cells in a loose connective tissue matrix containing stout collagen fibers and rare entrapped axons ( figure 6 ) .
this has been referred to as a  shredded carrot  appearance . at the patient 's 1-week postoperative office visit , his pain had completely resolved .
no focal sensory or motor deficits were found on neurological examination , though the patient reported an area of numbness measuring 2 x 3 inches in his left thoracolumbar area .
with the patient prepared and draped in a right lateral decubitus position , a 12-mm incision was made off of the tip of the twelfth rib .
an ethicon x - cel 12-mm optical port ( ethicon , somerville , nj ) was placed under direct endoscopic control into the pneumoretroperitoneum .
the retroperitoneum was further expanded by using a dissection balloon ( u. s. surgical inc . ,
two 8-mm robotic ports were then placed subcostally , one in the posterior axillary line , and the other in the anterior axillary line ( figure 3 ) .
a 12-mm port was placed above the iliac crest in the anterior axillary line , and a 5-mm port was placed just above and medial to it . docked robot , with 2 working arms , one arm attached to the endoscope , and 2 additional assistant 's ports .
the psoas muscle was identified and dissected medially and superiorly , until the diaphragm was noted .
the kidney , within gerota 's fascia , was mobilized along its posterior surface and retracted medially .
the diaphragm was incised vertically over the mass , and the anterior surface of the mass was dissected until its upper and lower margin could be clearly discerned ( figure 4 ) .
initial view of tumor through robotic endoscope with bipolar serrated graspers in the left robotic hand , monopolar electrosurgical scissors in the right robotic hand , and assistant operated irrigation / suction inferiorly .
the neurosurgeon then sat at the robotic console , while the urologic surgeon assisted at the side of the operating table . the robotic endoscope ( 12 mm ) and 2 robotic arms ( 8 mm )
bipolar serrated graspers were placed in the left robotic hand , and monopolar electrosurgical scissors were placed in the right robotic hand .
the tumor capsule was coagulated with the bipolar graspers and incised with the activated scissors .
the tumor capsule was extremely thin and friable ; however , the tumor was not soft enough to be removed with suction . in this fashion ,
an intracapsular tumor debulking was accomplished , with the resected tumor pieces removed by the laparoscopic graspers and suction operated by the urologic surgeon . after removing one third of the tumor
, enough space was made to elevate the posterior aspect of the tumor revealing the tumor attachment to its nerve root of origin ( figure 5 ) .
the nerve was coagulated and transected , freeing the remaining , which was placed into an entrapment sack .
fibrin glue was placed over the nerve root to prevent leakage of cerebral spinal fluid .
a small pleurotomy occurred during the tumor resection ; to evacuate the pneumothorax , a 10f cope loop thoracostomy tube was placed percutaneously into the left hemithorax .
the robot was used to close the pleurotomy with a running 40 chromic suture ; the diaphragm was closed using silk suture and lapra - ty clips .
the total operative time was 5.3 hours , of which approximately 2 hours was robotic console time .
the estimated blood loss was less than 50 ml . a postoperative chest x - ray in the postanesthesia care unit showed no pneumothorax .
the chest tube was removed in the postanesthesia care unit , and repeat chest x - rays confirmed no pneumothorax had developed . the patient was discharged home on postoperative day 2 ; there were no focal neurological deficits .
while recovering in the hospital , the patient 's pain was controlled with oral morphine cr ( 30 mg ) , given every 8 hours for a total of 7 doses .
he was also given his usual dose of gabapentin ( 200 mg , 3 times a day ) . at discharge ,
the patient was given hydrocodone / acetaminophen ( 5/500 ) to be taken orally as needed every 4 hours for pain , and morphine cr ( 30 mg ) to be taken orally as needed every 12 hours for pain for up to 1 week .
pathological examination of the operative specimen showed it to be a neurofibroma , composed of stellate and spindle - shaped cells in a loose connective tissue matrix containing stout collagen fibers and rare entrapped axons ( figure 6 ) .
this has been referred to as a  shredded carrot  appearance . at the patient 's 1-week postoperative office visit , his pain had completely resolved .
no focal sensory or motor deficits were found on neurological examination , though the patient reported an area of numbness measuring 2 x 3 inches in his left thoracolumbar area .
neurofibromatosis type i ( nf-1 ) , known as von recklinghausen disease , is an autosomal dominant disorder carried on chromosome 17 .
the incidence has been measured to be approximately 1 in every 3000 births . besides the previously described identifying characteristics of nf-1 ( neurofibromas , pigmented skin lesions , and lisch nodules ) , it has the potential for multiple tumors ( approximately 20% of nf patients ) and the development of malignancies that have the greatest impact on quality and length of life .
average length of life for patients with nf-1 has been determined by a retrospective chart review to be 54.1 years , compared with 70.1 years for the general population .
patients with neurofibromatosis type 1 were 1 time to 2 times more likely to have a malignant neoplasm at the time of death than the unaffected population ; overall 2% to 16% of patients with neurofibromas develop neural sheath malignancies .
although there is no proven link between neurofibromatosis and melanoma , there have been almost 30 cases of melanoma reported in patients with neurofibromatosis .
optic gliomas develop in 15% of patients ; however , only 2% to 5% are symptomatic .
the drive to increase the precision of dissection has long been a focus of neurosurgical procedures and has been the impetus for microsurgical techniques . in this regard , robotic technology may prove to be an invaluable tool for applying minimally invasive techniques for tissue and nerve - sparing purposes .
the current da vinci system supplies the surgeon with 4 robotic arms , one of which controls the high - definition , full color , 3-d magnified endoscope .
the surgeon 's movements are translated to the robotic arm movements without any noticeable delay and with up to 1:5 motion scaling ; the robotic arms have 6 degrees of freedom . also important , especially in the realm of neurosurgery , is the ability of the robot computer to automatically eliminate any surgeon hand tremor and provide the surgeon with a 540 wrist action . in this young patient with a high risk of eventually requiring additional surgeries , we thought that a minimally invasive approach would be advantageous over an open procedure , as it would allow faster recovery and small incisions .
laparoscopic success of a retroperitoneal resection of a neurofibroma has already been reported in 3 separate cases ; however , only one case was done with a pure laparoscopic approach , as was ours for the initial dissection , while the other 2 utilized a hand - assisted technique .
the combination of the pure laparoscopic approach and the latest in robotic technology enabled us to complete the first successful robotic removal of a spinal tumor with minimal resulting morbidity , a brief hospital stay , and rapid postoperative recovery .
we believe that the advent of robotic technology will prove to be a boon to the neurosurgeon . for the first time
, the surgeon will be afforded an absolutely stable tremor - free working platform endowed with 6 degrees of freedom and a 540 wrist with up to 1:5 motion scaling .
the last will afford the surgeon the ability to make the finest of movements in a highly controlled manner . also , the endoscopic view with its 3d and high definition attributes provides an astounding image that can provide magnification in the 12x to 40x range .
lastly , and certainly not least , the ergonomic surgeon 's console provides the surgeon with a seated working environment , free of gown , gloves , and mask , that provides a level of surgeon comfort , heretofore not possible .
robotic - assisted laparoscopic resection of a retroperitoneal paraspinal neurofibroma was successfully completed for the first time .
further and more extensive applications of the da vinci robot system within the field of neurosurgery await .
 objective : robotic technology has been used in a variety of surgical procedures for its 3d magnification and precision . minimally invasive techniques have already become common in neurosurgery ; however , robotic - assisted procedures in neurosurgery are still a relatively new frontier . 
 this report describes the first use of robotic technology to resect a left thoracolumbar neurofibroma.case report : a 19-year - old male with a family history of neurofibromatosis was diagnosed with a suspected 3-cm x 4-cm neurofibroma in the t12-l1 left paraspinal area . 
 his only complaint was back pain requiring narcotic analgesics . 
 he had no other findings on physical examination or laboratory / radiologic workup.methods:after consulting urologic robotic surgeons , it was agreed to use the da vinci robot ( intuitive surgical , sunnyvale , ca ) for the resection of this mass . 
 following retroperitoneal laparoscopic access , the urologic surgeons opened the diaphragm and began the initial mobilization of the mass laparoscopically . the robot was docked , and the neurosurgeon operated the robot at the console to resect the mass from its nerve origin . 
 there were no complications , and the mass , a confirmed neurofibroma , was completely removed . 
 the patient was discharged on postoperative day 2 ; his back pain resolved , requiring no analgesia by the end of the first postoperative week.conclusion:this case provides early evidence that robotic assistance can be successfully used for the resection of a paraspinal neurofibroma . 
INTRODUCTION
CASE REPORT
Operative Procedure
DISCUSSION
CONCLUSION