various types of cystic lesions are confronted in the spinal canal and are classified in respect of their relationship to the adjacent structures and nature of the cyst content . amongst them , cerebrospinal fluid ( csf)-filled meningeal cysts constitute for the majority of the cases [ 11 , 18 ] and are called as  arachnoid cysts ,   diverticula ,  [ 5 , 9 ] or  pouches  . depending on the location , size , and mechanism of origin , the clinical course varies between asymptomatic , incidentally - diagnosed cases   to severe myelopathy . when they communicate freely with subarachnoid space , fluctuating symptoms related to changes in csf pressure may occur [ 8 , 9 ] . although arachnoid cysts can be observed anywhere along the length of the spinal canal , middle , and lower thoracic regions constitute for the most frequently involved areas . when progressive neurological findings exist , surgical treatment is warranted . surgical techniques include excision , fenestration , or placement of a cysto - subarachnoid shunt [ 6 , 11 ] , as well as some less invasive techniques that have been proposed recently . we present a case with a giant cervicothoracic extradural arachnoid cyst and its surgical management . several features of the cyst , such as its size , location , and clinical features make the case extremely unusual . a 57-year - old male was referred with symptoms of difficulty in walking , weakness , numbness , and thinning of arms and legs , and impotency , which had all begun two years before . the patient had suffered a serious traffic accident when he was 10  years old , and has had a contracture of his right hand since then . neurological examination revealed spastic quadriparesis predominantly on the left side ( left upper extremity proximally had 2/5 muscle strength , distally had 1/5 , and left lower extremity globally had 4/5 ) , left - sided atrophy , hypoesthesia and hypoalgesia in c5 - c8 dermatomes , hypoactivity of deep tendon reflexes at the upper extremity , hyperactivity in patellar reflex , and babinski sign . the anal sphincter tonus was weak , and the patient reported an intermittent sphincter control defect . cervical radiographs showed widening of the left neural foramina and the spinal canal . magnetic resonance imaging ( mri ) revealed an extradural cystic mass extending from c2 to t2 vertebral bodies , located left anterolaterally , compressing the spinal cord ( figs . it had the same csf intensity on t1 and t2-weighted images and showed no contrast enhancement . the lesion had caused a concavity in the related vertebral bodies and widening of the neural foramina on the left side . electrophysiological tests reported chronic severe neurogenic involvement and a delay in the somato - sensorial evoked potential responses in c6 - t1 innervated muscles . 1t2-weighted median ( a ) , slightly left paramedian ( b ) , and left paramedian ( c ) sagittal magnetic resonance images of the cervical region shows a cystic mass extending from c2 to t2 vertebral bodies , located left anterolaterally , enlarging left neural foramina ( arrows ) . 2axial magnetic resonance image taken from t1 level shows the csf - filled extradural cyst , located left anterolaterally , compressing the spinal cord ( sc spinal cord ) t2-weighted median ( a ) , slightly left paramedian ( b ) , and left paramedian ( c ) sagittal magnetic resonance images of the cervical region shows a cystic mass extending from c2 to t2 vertebral bodies , located left anterolaterally , enlarging left neural foramina ( arrows ) . ( arrowheads spinal cord ) axial magnetic resonance image taken from t1 level shows the csf - filled extradural cyst , located left anterolaterally , compressing the spinal cord ( sc spinal cord ) a c4  t2 laminotomy was performed . an extradural cystic lesion , full of csf and having a thin and transparent membrane , was observed compressing the dural sac . c7 foramina and there was an active flow of csf to the cyst through the defects located at the exiting points of these three roots . the cyst wall was excised and the dural defects were repaired using muscle pieces and sutures . despite some degree of the spinal cord and dural sac expansion , the epidural and subarachnoid spaces left enlarged , since the canal was widened . the epidural space was left unfilled for the fear of compression . although the spasticity gradually improved during two years of follow - up , muscle strength and other neurological findings did not change . there are various classifications based on etiology , histopathology , or localization of the cysts . extradural cysts include arachnoid cysts , synovial cysts , ganglias , cysts of ligamentum flavum , and cysts originating from the intervertebral discs . intradural cysts include arachnoid cysts , enterogen ( endodermal , neuroenteric ) cysts , and ependymal cysts [ 3 , 6 , 7 , 10 , 12  15 , 18 ] . it was documented that congenital asymptomatic cysts could enlarge due to trauma and become symptomatic . for example , the arachnoid cysts related to arachnoiditis are usually localized and small [ 6 , 18 ] . pulsatile csf dynamics , osmotic gradient between the subarachnoid space and cyst , and the valve - like mechanism between the cyst and subarachnoid space   may play an important role in the enlargement of spinal extradural arachnoid cysts . demonstrated that increased intra abdominal and intrathoracic pressure may lead to size changes of the spinal arachnoid cyst . a review demonstrated that arachnoid cysts involving the cervical region are extremely rare , that they never exceed three vertebral bodies in length , and that none extended into the thoracic region , except the case reported by safriel et al . . that case was an intradural arachnoid cyst situated anteriorly to the spinal canal extending between c5 and t3 levels . the presented cyst was extradural , located at the cervicothoracic region , anterolateral to the spinal cord , and involved eight vertebral bodies extending from c2 to t2 level . to the authors knowledge , there is no extradural arachnoid cyst reported in the literature matching that size . he had suffered a serious traffic accident when he was a child and consequently had a contracture in his left upper extremity . although there was an excessively long duration ( 45  years ) between trauma and appearance of new symptoms attributable to the cyst , the concordance of the former neurological deficit and location of the cyst convinced us that the etiology of the cyst might have been the childhood trauma . during the surgery , we did not observe any laminar signs that indicated a sustained compression fracture on the posterior elements . thus , stretching and partial avulsion of the roots may have caused arachnoid and dural tearing during the childhood trauma , causing subsequent collection of the csf at the epidural space , communicating freely both subarachnoid space and dural sleeves of the roots . indeed , the occurrence of multiple dural defects , through which the csf exits , is very rare . this point makes an extra implication on the case and further supports the avulsion theory as the cause of multiple dural tearings , since the neurological deficit due to childhood trauma is concordant with multiple root involvement . long - standing progressive enlargement of the cyst explains radiological signs such as eroded vertebral bodies and enlarged intervertebral foramina . the pathogenesis , etiology , and treatment of the spinal arachnoid cyst have not been well established because of its rarity . symptomatic cases require surgical intervention . for long segment involvements , hemilaminectomy or laminotomy , as was performed in the current case is preferable to laminectomy in order to prevent postoperative deformity . in surgery neurological recovery depends on the size of the cyst and degree and duration of the spinal cord compression . a long - standing spastic myelopathy is unlikely to have a significant improvement , as we observed in the current case . except spasticity , thus , in delayed cases , surgery may be taken and should be offered as a prophylactic intervention to prevent further impairment , rather than a curative one . in conclusion , although probably traumatic , it had extremely delayed clinical presentation , its location was unusual , and as an extradural cervicothoracic arachnoid cyst , it was the largest amongst those reported .
the pathogenesis , etiology , and treatment of the spinal arachnoid cyst have not been well established because of its rarity . 
 a 57-year - old male was presented with spastic quadriparesis predominantly on the left side . 
 his radiological examination showed widening of the cervical spinal canal and left neural foramina due to a cerebrospinal fluid - filled extradural cyst that extended from c2 to t2 level . 
 the cyst was located left anterolaterally , compressing the spinal cord . through a c4t2 laminotomy , 
 the cyst was excised totally and the dural defect was repaired . 
 several features of the reported case , such as cyst size , location , and clinical features make it extremely unusual . 
 the case is discussed in light of the relevant literature .