Role of the O-arm and Computer-assisted Navigation of Safe Screw Fixation in Children with Traumatic Rotatory Atlantoaxial Subluxation

STUDY DESIGN: A retrospective analysis of 7 patients with traumatic rotatory atlanto-axial subluxation. OVERVIEW OF LITERATURE: Cases of traumatic rotatory atlantoaxial subluxation in children are difficult to be stabilized. Surgical challenges include: narrow pedicles, medial vertebral arteries, vertebral artery anomalies, fractured pedicles or lateral masses, and fixed subluxation. The use of O-arm and computer-assisted navigation are still tested as aiding tools in such operative modalities. PURPOSE: Report of clinical series for evaluation of the safety of use of the O-arm and computed assisted-navigation in screw fixation in children with traumatic rotatory atlantoaxial subluxation. METHODS: In the present study, 7 cases of rotatory atlantoaxial traumatic subluxation were operated between December 2009 and March 2011. All patient-cases had undergone open reduction and instrumentation using atlas lateral mass and axis pedicle screws with intraoperative O-arm with computer-assisted navigation. RESULTS: All hardware was safely placed in the planned trajectories in all the 7 cases. Intraoperative O-arm and computer assisted-navigation were useful in securing neural and vascular tissues safety with tough-bony purchases of the hardware from the first and only trial of application with sufficient reduction of the subluxation. CONCLUSIONS: Successful surgery is possible with using the intraoperative O-arm and computer-assisted navigation in safe and proper placement of difficult atlas lateral mass and axis pedicle screws for rotatory atlantoaxial subluxation in children.

Intra-operative indocyanine green-videoangiography [ICG-VA] in intracranial aneurysm surgery

To assess the feasibility and potential utility of the intra-operative ICG-VA in assessment of the unexpected residual aneurysm and major cerebral artery occlusion or stenosis after cerebral aneurysm surgery. Fifteen consecutive patients with anterior circulation aneurysms who underwent craniotomy and clipping of the aneurysms were included in this study. Intraoperative ICG-VA was performed in all cases after exposure of the aneurysm and the branches in the vicinity of the aneurysm or the parent vessel before clipping of the aneurysm and postclipping after the surgeon was satisfied that the aneurysm neck was completely obliterated. We analyzed the ICG images with regards to residual aneurysm or major arterial occlusion or stenosis and compared them to postoperative digital subtraction angiography [DSA] that served as a control. In 4 patients there were small residual neck detected by intraoperative ICG, which were immediately corrected by clip readjustment for immediate correction and replacement and this was confirmed by the postoperative DSA. No major arterial occlusion or stenosis was detected in ICG or postoperative DSA images. ICG-VA is a simple, fast method for blood flow assessment that provides a real-time information about the blood flow in vessels of different sizes as well as the obliteration of the aneurysm. It may serve as a method to improve the obliteration rate of intracranial aneurysms

Surgical clipping of ruptured anterior circulation cerebral aneurysms: KFMC experience

The aim of this study is to analyze the outcome of surgical clipping of the ruptured anterior circulation aneurysms with emphasis on the prognostic factors affecting this outcome. This is a retrospective study reviewing a database detailing all patients with ruptured anterior circulation aneurysm cases admitted in King Fahd Medical City from January 2006 - June 2007. Aneurysms were classified by location and size. Clinical condition was graded on admission according to classification of the World Federation of Neurological Surgeons [WFNS] grading. Outcomes were evaluated at discharge using the modified Rankin scale. Outcomes examined with overall rates of mortality, procedural complication and morbidity. Twenty-five patients, with 29 anterior circulation cerebral aneurysms underwent surgical clipping. According to WFNS, 15 patients were grade 1, 4 patients were grade 2, 4 patients were grade 3, and one patient was grade 4 and one patient was grade 5. Ten aneurysms [34.5%] were located in anterior communicating artery, 10 aneurysms [34.5%] in internal carotid artery segments, 5 aneurysms [17.2%] in anterior cerebral artery and 4 aneurysms [13.8%] in middle artery. The outcome according to Rankin score, 17 patients [68%] discharged with score 0, 3 patients [12%] with score 1, one patient [4%] with score 3, one patient [4%] with score 5 and 3 deaths [12%] score6. Surgical clipping is safe and reliable treatment of anterior circulation cerebral aneurysms. Clinical grade on admission is the most important determining factor for outcome

Surgical choices for cervical OPLL

Ossification of the posterior longitudinal ligament [OPLL] is a common cause of cervical myelopathy, especially in Japan, and is more common in males. OPLL is classified into four types: segmental, continuous, mixed and focal. Different surgical approaches are being used to treat this disease, including laminectomy, laminoplasty and anterior, either resecting the ligament or decompressing the cord using the floating technique, leaving the ossified ligament in place. This study included sixteen patients with cervical OPLL treated at Alexandria main University Hospital during a period of two years [July 2001 to July 2003]. The age of the patients ranged from 45-67 years, with a mean age of 58.12 years. Fourteen patents were males and two were females. All patients excluding 2 presented with gradual progressive manifestations. The remaining 2 patients presented with acute onset quadriplegia after minor trauma. Upper extremity weakness and clumsiness, gait difficulty, sphincter dysfunction and neck pain were the most common complaints. Clinical evaluation and outcome of the patients was carried out using the Nurick scale. Fifteen of our patients suffered radiculomyelopathy. One patient with focal OPLL suffered radiculopathy in the distribution of right C6 root. Ten patients improved and six patients remained stationary during a follow-up period of six months. Plain x-rays, magnetic resonance imaging and computed tomography scan were done for all patients. Ossification posterior longitudinal ligament was found to be the continuous type in thirteen cases, mixed in two cases and focal in one. The maximal thickness of the OPLL was 7 mm with a range of 3-7 mm and a mean of 4.3 mm. The most commonly affected levels were C2-C4. The effective canal diameter ranged from 5-13 mm with a mean of 9.8 mm. In this study we used conventional laminectomy in eleven cases, open door laminoplasty in four cases and the anterior approach in only one patient with focal OPLL. We measured the improvement according to the Nurick scale. Ten patients improved and six patients remained stationary during a follow-up period of six months. We concluded from this study that OPLL should be kept in mind in the differential diagnosis in cases of cervical myelopathy. The effective canal diameter and the range of motion of the cervical spine are the most important factors affecting the clinical picture in cases of OPLL. Early surgery is recommended for cases of OPLL because better results are obtained in younger patients with short duration of symptoms. Laminectomy is a simple surgical option in cases of continuous type OPLL, with a stable spine as proved by dynamic study. Laminoplasty is better used in extensive involvement of the spine if the dynamic films show a high range of movement. Anterior approach has the risk of neural injury and is better avoided, especially if dural invasion could be identified in the preoperative imaging study. Anterior approach can be used in focal type OPLL and if used in extensive OPLL. The floating technique is safer than other methods to excise the OPLL