Lorenzo Alvaro

Endoscopic transnasal odontoid resection to decompress the bulbo-medullary junction: a reliable anterior minimally invasive technique without posterior fusion

PurposeAnterior decompression of the craniovertebral junction is reserved to patients with irreducible ventral bulbo-medullary lesions and rapidly deteriorating neurological functions. Classically performed through the transoral approach, the exposure of this region can be now achieved by a minimally invasive endonasal endoscopic approach (EEA).MethodsFour patients with irreducible, anterior bulbo-medullary compression due to rheumatoid pannus and basilar invagination were enrolled. The imaged-guided EEA was used to resect the odontoid process, trying to preserve the C1 anterior arch.ResultsNeurological improvement and adequate bulbo-medullary decompression were obtained in all patients. In two cases, anterior C1 ring was preserved. These patients did not required a posterior fusion.ConclusionsCompared with the standard transoral technique, the EEA provides the same good exposure but with potentially less complications. The preservation of the anterior C1 arch can contribute to avoid cranial settling and posterior fusion with its related risk of subaxial instability.

Endoscopic endonasal odontoidectomy with anterior C1 arch preservation in elderly patients affected by rheumatoid arthritis

BACKGROUND CONTEXT Rheumatoid arthritis is the most common inflammatory disease involving the spine with predilection for the craniovertebral segment. Surgery is usually reserved to patients with symptomatic craniovertebral junction (CVJ) instability, basilar invagination, or upper spinal cord compression by rheumatoid pannus. Anterior approaches are indicated in cases of irreducible ventral bulbo-medullary compression. Classically performed through the transoral approach, the exposure of this region can be now achieved by a minimally invasive endonasal endoscopic approach (EEA). PURPOSE The aim of this article is to demonstrate the feasibility of performing an odontoidectomy and a rheumatoid pannus removal by a minimally invasive EEA, preserving the anterior C1 arch continuity and avoiding a posterior fixation procedure. STUDY DESIGN Technical description and cohort report. METHODS We report three cases of elderly patients with a long history of rheumatoid arthritis and irreducible anterior bulbo-medullary compression secondary to basilar invagination and/or rheumatoid pannus. Anterior decompression was achieved by an endonasal image-guided fully endoscopic approach. RESULTS Neurological improvement and adequate bulbo-medullary decompression were obtained in all cases. The anterior C1 arch continuity was preserved, and none of the patients required a subsequent posterior fixation. CONCLUSIONS Anterior decompression by a minimally invasive EEA could represent an innovative option for the treatment of irreducible ventral CVJ lesions in elderly patients with rheumatoid arthritis. This approach permits the preservation of the anterior C1 arch and the avoidance of a posterior fixation, thus preserving the rotational movement at C0-C2 segment and reducing the risk of a subaxial instability development.

Minimally invasive surgery for benign intradural extramedullary spinal meningiomas: experience of a single institution in a cohort of elderly patients and review of the literature.

Meningiomas of the spine are the most common benign intradural extramedullary lesions and account for 25%–46% of all spinal cord tumors in adults. The goal of treatment is complete surgical resection while preserving spinal stability. Usually, these lesions occur in the thoracic region and in middle-aged women. Clinical presentation is usually nonspecific and the symptoms could precede the diagnosis by several months to years, especially in older people, in whom associated age-related diseases can mask the tumor for a long time. We report a series of 30 patients, aged 70 years or more, harboring intradural extramedullary spinal meningiomas. No subjects had major contraindications to surgery. A minimally invasive approach ( hemilaminectomy and preservation of the outer dural layer) was used to remove the tumor, while preserving spinal stability and improving the watertight dural closure. We retrospectively compared the outcomes in these patients with those in a control group subjected to laminectomy or laminotomy with different dural management. In our experience, the minimally invasive approach allows the same chances of complete tumor removal, while providing a better postoperative course than in a control group.

Endoscopic endonasal approach for the treatment of a large clival giant cell tumor complicated by an intraoperative internal carotid artery rupture

Giant cell tumors (GCTs) are primary bone neoplasms that rarely involve the skull base. These lesions are usually locally aggressive and require complete removal, including the surrounding apparently healthy bone, to provide the best chance of cure. GCTs, as well as other lesions located in the clivus, can nowadays be treated by a minimally invasive fully endoscopic extended endonasal approach. This approach ensures a more direct route to the craniovertebral junction than other possible approaches (transfacial, extended lateral, and posterolateral approaches). The case reported is a clival GCT operated on by an extended endonasal approach that provides another contribution on how to address one of the most feared complications attributed to this approach: a massive bleed due to an internal carotid artery injury.

Piezosurgery for osteotomies in orbital surgery: Our experience and review of the literature.

INTRODUCTION Piezoelectric bone surgery, simply known as Piezosurgery(®), is a new promising technique for bone cutting based on ultrasonic microvibrations that allows to perform precise and thin osteotomies with soft tissue sparing. PRESENTATION OF CASE A 45-years-old woman presenting with progressive left ocular pain, diplopia on the lateral left gaze, and visible exophthalmos was admitted to our department. CT scan and MRI images documented a left supero-lateral orbital lesion. A left lateral orbitotomy using the piezoelectric scalpel was performed. The tumour (lacrimal gland lymphoma) was completely removed with no injuries to the orbital structures and with a perfect realignment of the bone stumps. DISCUSSION High powered pneumatic osteotome are commonly used to perform craniotomies. Large bone cutting groove and high temperatures developing at the contact site could produce an uneasy bone healing. The use of a piezoelectric scalpel allows to realize precise and thin osteotomies, facilitating craniotomys borders ossification and avoiding injuries to non-osseous structures. CONCLUSION Widely used in Oral and Maxillofacial Surgery, Piezosurgery(®) can also be useful in neurosurgical approaches in order to obtain a faster bone flap re-ossification, a better aesthetic result, and a lower risks of dural layer and soft tissue damage.

Improving the endoscopic endonasal transclival approach: the importance of a precise layer by layer reconstruction

Abstract Background. The endoscopic endonasal transclival approach (EETCA) is a minimally-invasive technique allowing a direct route to the base of implant of clival lesions with reduced brain and neurovascular manipulation. On the other hand, it is associated with potentially severe complications related to the difficulties in reconstructing large skull base defects with a high risk of postoperative cerebrospinal fluid (CSF) leakage. The aim of this paper is to describe a precise layer by layer reconstruction in the EETCA including the suture of the mucosa as an additional reinforcing layer between cranial and nasal cavity in order to speed up the healing process and reduce the incidence of CSF leak. Methods. This closure technique was applied to the last six cases of EETCA used for clival meningiomas (2), clival chordomas (2), clival metastasis (1), and craniopharyngioma with clival extension (1). Results. After a mean follow-up of 6 months we had no one case of postoperative CSF leakage or infections. Seriated outpatient endoscopic endonasal controls showed a fast healing process of nasopharyngeal mucosa with less patient discomfort. Conclusions. Our preliminary experience confirms the importance of a precise reconstruction of all anatomical layers violated during the surgical approach, including the nasopharygeal mucosa.

Fully endoscopic endonasal anterior C1 arch reconstruction as a function preserving surgical option for unstable atlas fractures

Dear Editor, The management of isolated C1 atlas fractures is still a matter of debate. Stable atlas fractures are treated conservatively, while unstable ones are surgically managed, usually by posterior occipito-cervical or C1-C2 fixations [1]. These procedures provide craniovertebral junction (CVJ) stability, but their serious disadvantage is the elimination of the rotational mobility at C1-C2 segment and the abolition of flexion-extension movement at C0-C1, providing an increased risk of lower cervical spine degeneration [2]. C1ring reconstruction (C1-RR), by an anterior transoral or transcervical approach, was recently introduced in order to restore CVJ stability with motion preservation [3, 4]. We report two cases of atlas fracture non-union after conservative treatment that developed C1 lateral masses displacement with cranial settling, treated by a fully endoscopic endonasal anterior C1-RR using autologous bone graft (Fig. 1a and b). The only definitive anatomical violation during the surgical procedure was the resection of a small portion of the posterior edge of the nasal septum to ease bilateral application of instrumentation. The posterior part of the hard palate was thinned to increase the angle of “nasopalatine line” (K-line) [5]. After the identification of the anterior C1 tubercle, by anatomical landmarks and neuronavigation, a small linear incision was made on the nasopharyngeal mucosa [6, 7]. After subperiosteal preparation of the anterior C1 arch, the fibrotic material between bony fragments, related to the pseudarthrosis process, was completely cleaned (Fig. 1c). The migrated odontoid tip was then removed for adequate bulbo-medullary decompression. The autologous bone, obtained from the removed odontoid tip, was packed in the fracture space for C1 arch reconstruction and spread on the underlying clivus for the “in situ” anterior atlanto-occipital stabilization. To secure the bone graft, it was mixed with autologous bone marrow and blood, and fixed to the anterior C1 arch by using titanium mesh and screws. This step was useful just to guarantee temporary stabilization of the autologous bone during the arthrodesis process and to avoid the further displacement of C1-C2 articular masses. Finally, the nasopharyngeal defect was sutured. Tracheostomy was not necessary. In both patients, neck pain disappeared, no major complications occurred, and oral feeding was re-started the next day after surgery. At 1-year follow-up, the range of motion of the cervical spine was only slightly reduced (15 % in rotation) and the CT scan demonstrated the anterior C1 arch reconstruction with arthrodesis and anterior atlanto-occipital fusion between the atlas and lower clivus (Fig. 1d and e). Posterior occipito-cervical or C1C2 fixation was not required. The seriated endoscopic controls showed the fast and complete healing of the nasopharyngeal mucosa (Fig. 1f). In order to treat unstable atlas fractures with motion preservation, some authors suggested the C1-RR rather than posterior fixation [3, 4, 8]. Biomechanical studies have confirmed the importance of the C1-RR for restoring craniovertebral stability [3, 8, 9]. However, the most used transoral approach requires prolonged intubation and need for nasogastric tube M. Iacoangeli :A. Di Rienzo : L. Alvaro :M. Scerrati Department of Neurosurgery, Umberto I General Hospital, Università Politecnica delle Marche, Ancona, Italy

Combined endoscopic transforaminal-transchoroidal approach for the treatment of third ventricle colloid cysts.

Colloid cysts are histologically benign lesions whose primary goal of treatment should be complete resection to avoid recurrence and sudden death. Open surgery is traditionally considered the standard approach, but, recently, the endoscopic technique has been recognized as a viable and safe alternative to microsurgery. The endoscopic approach to colloid cysts of the third ventricle is usually performed through the foramen of Monro. However, this route does not provide adequate visualization of the cyst attachment on the tela choroidea. The combined endoscopic transforaminal-transchoroidal approach (ETTA), providing exposure of the entire cyst and a better visualization of the tela choroidea, could increase the chances of achieving a complete cyst resection. Between April 2005 and February 2011, 19 patients with symptomatic colloid cyst of the third ventricle underwent an endoscopic transfrontal-transforaminal approach. Five of these patients, harboring a cyst firmly adherent to the tela choroidea or attached to the middle/posterior roof of the third ventricle, required a combined ETTA. Postoperative MRI documented a gross-total resection in all 5 cases. There were no major complications and only 1 patient experienced a transient worsening of the memory deficit. To date, no cyst recurrence has been observed. An ETTA is a minimally invasive procedure that can allow for a safe and complete resection of third ventricle colloid cysts, even in cases in which the lesions are firmly attached to the tela choroidea or located in the middle/posterior roof of the third ventricle.

Neurological outcome in a series of 58 patients operated for traumatic thoracolumbar spinal cord injuries.

Background: Traumatic thoracolumbar spinal fractures represent approximately 65% of all traumatic spinal fractures and are frequently associated to permanent disability with significant social and economic impact. These injuries create severe physical limitations depending on neurological status, level of fracture, severity of injury, patient age and comorbidities. Predicting neurological improvement in patients with traumatic spinal cord injuries (SCIs) is very difficult because it is related to different preoperative prognostic factors. We evaluated the neurological improvement related to the preoperative neurological conditions and the anatomic level of spinal cord injury. Methods: From January 2004 to June 2010, we operated 207 patients for unstable thoracolumbar spinal fractures. We carried out a retrospective analysis of 69 patients with traumatic SCIs operated on by a posterior fixation performed within 24 hours from the trauma. The preoperative neurological conditions (ASIA grade), the type of the fracture, the anatomic level of spinal cord injury and the postoperative neurological improvement were evaluated for each patient. Results: The ASIA grade at admission (P = 0,0005), the fracture type according to the AO spine classification (P = 0,0002), and the anatomic location of the injury (P = 0,0213) represented predictive factors of neurological improvement at univariate analysis. The preoperative neurological status (P = 0,0491) and the fracture type (P = 0,049) confirmed a positive predictive value also in the multivariate analysis. Conclusions: Our study confirms that the preoperative neurological status, the fracture type and the anatomic location of the fracture are predictive factors of the neurological outcome in patients with spinal cord injury.

Piezosurgery as a further technical adjunct in minimally invasive supraorbital keyhole approach and lateral orbitotomy.

OBJECTIVE One of the problems in neurosurgery is how to perform rapid and effective craniotomies that minimize the risk of injury to underlying eloquent structures. The traditional high-powered pneumatic tools and saws are efficient in terms of speed and penetration, but they can provoke bone necrosis and sometimes damage neurovascular structures. As an alternative, we evaluated the piezoelectric bone scalpel (piezosurgery), a device that potentially allows thinner and more precise bone cutting without lesioning neighboring delicate structures, even in the case of accidental contact. MATERIAL AND METHODS From January 2009 to December 2011, 20 patients (8 men and 12 women), 19 to 72 years of age (mean: 49.3 years) were treated using piezosurgery. Surgery was performed for the removal of anterior cranial fossa meningiomas, orbital tumors, and sinonasal lesions with intracranial extension. RESULTS The time required to perform craniotomy using piezosurgery is a few minutes longer than with traditional drills. No damage was observed using the piezoelectric device. Follow-up clinical and neuroradiologic evaluation showed a faster and better ossification of the bone flap with good esthetic results. CONCLUSIONS Piezosurgery is a new promising technique for selective bone cutting with soft tissue preservation. This instrument seems suitable to perform precise thin osteotomies while limiting damage to the bone itself and to the underlying delicate structures even in the case of unintentional contact. These advantages make the piezoelectric bone scalpel a particularly attractive instrument in neurosurgery.