The patient was operated by me for extruded disc L4-5 10-April-2007. The patient then came several times for cervical problems and was treated conservatively. The patient then came 31-March-2015 complaining of LBP for 1 month with numbness big toes both feet. She was limping with SLRS 70 degrees right side, 60 degrees left side with pain both sides. There is hypalgesia below the right knee and weak dorsiflexion both feet 4/5. There is also weak right quadriceps -4/5 and left 4/5. The patient was sent for investigations. The patient then came 26-April-2015 with MRI of the cervical spine performed 06-June-2015 showing bulge disci C3-4, 5-6 with a small mass behind the spinal cord at D6-7 level. Lumbar spine ruled out recurrence of L4-5. The patient was advised to wait the progression of the mass. The patient then came 31-August-2015 telling that the numbness both legs increased more the right with fainting attacks with bifrontal headache.

On examination: the patient is limping with scoliotic stance. SLRS was 70 degrees with pain in the right. There is weak grip right hand 4/5, extension same hand -4/5 and right triceps muscle 3/5. Weak dorsiflexion right foot 3/5 and planterflexion same foot -4/5 and and right quadriceps 4/5 with hypalgesia below the right C6 territory.

The patient was sent for MRI investigations. MRI of the brain performed 08-September-2015 was normal, lumbar spine showing no recurrence of L4-5. Dorsal spine showing the above mentioned mass at the level of D6-7 compressing the spinal cord, which could be an epidermoid or arachnoid cyst. In comparison with the previous MRI there is slight enlargement of the mass.

Using the C-arm, the level of D6-7 was identified and projectional laminectomy was performed. There is an extradural elongated cyst compressing the dura from behind. It was dissected of the dura and totally removed and sent for histologic verification. There is a tiny dural defect at the most upper left corner of the removed cyst, which was stitched by 6 zero nylon with 2 layers. There was no CSF leak, nor after removal of the cyst, nor after stitch repair. It seems that the arachnoid cyst had a narrow neck. Routine closure of the wound.

Smooth postoperative recovery. The power of right leg became better. She was sent to the ward.

The patient has a progressing mass with progressing clinical deterioration. Surgical resection is the best solution.

Usually the arachnoid cyst is intradural in localization, but this one was extradurally located with very narrow neck.