Cervical spinal cord infarction after posterior fossa surgery: a case-based update

New-Onset Paralysis following Biopsy of a Retroperitoneal Mass with Intraspinal Extension in a Pediatric Patient

Image-guided percutaneous biopsies are routine, safe procedures and complications are infrequent and usually directly related to the biopsy itself. This report describes a biopsy of a retroperitoneal mass with extension into the spinal canal, following which the patient developed paralysis unrelated to the biopsy itself but secondary to spinal cord ischemia during the procedure. Multiple factors contributed to the ischemia, including prone positioning, compression of spinal vasculature by the mass, low arterial pressures, and an extended duration of anesthesia. While the patient eventually recovered neurologic function, it is an important reminder to consider individual patient factors that may complicate typically routine procedures. In masses with intraspinal extension, patient positioning is critical to prevent positional ischemia, and maintaining elevated mean arterial pressures is crucial for ensuring adequate spinal perfusion throughout the procedure.

Paralysis Caused by Spinal Cord Injury After Posterior Fossa Surgery: A Systematic Review

OBJECTIVE

Paralysis (paraplegia or quadriplegia) after posterior fossa surgery is a rare but devastating complication. We investigated previous reports of this complication to examine similarities among patients, risk factors, and methods by which it may be prevented.

METHODS

A systematic review was completed according to PRISMA guidelines. Electronic databases were searched until November 2019 using keywords "paraplegia," "quadriplegia," or "spinal cord injury" added to "posterior fossa surgery."

RESULTS

Thirteen case reports published between 1996 and 2019 were included. Five (38.5%) involved quadriplegia/quadriparesis and 8 (61.5%) involved paraplegia after surgery. Ten cases (76.9%) were tumor resections and 3 (23.1%) were posterior fossa decompressions (2 for Chiari malformations and 1 for Morquio syndrome). Seven surgeries (53.8%) were performed in the sitting position and 6 (46.2%) were prone. Proposed mechanisms of paralysis involved cervical hyperflexion yielding spinal cord ischemia in 8 patients (61.5%), arterial hypotension in 2 patients (15.4%), spinal cord compression from hematoma in 1 patient (7.7%), and decreased cardiac output in 1 patient (7.7%) (1 study did not propose a cause). Cervical hyperflexion was equally likely in the sitting and prone positions (4 patients each). Only 3 patients (23.1%) involved intraoperative complications (all cardiopulmonary in nature).

CONCLUSIONS

Paralysis after posterior fossa surgery often involves spinal cord infarction apparently caused by cervical hyperflexion. Extreme care during patient positioning is needed in both the sitting or prone positions. Electrophysiologic monitoring might enable early identification of spinal cord dysfunction to minimize or avoid this complication.

Postoperative Tetraplegia to a Child after Cerebellar Pilocytic Astrocytoma Excision at Prone Position: Case Report and Literature Review

BACKGROUND Various factors have been implicated in the pathogenesis of infarction after posterior fossa surgery such as venous air embolism, patient's position (seated or prone), hyperflexion of the neck, excessive spinal cord traction, cervical canal stenosis, and systemic arterial hypotension. The main aim of this case report was to elucidate a case in which hydrogen peroxide was implicated in a major and systemic complication after a neurosurgical procedure. CASE REPORT We describe the case of a 5-year-old female patient who was admitted to our hospital because of a cerebellar hemispheric astrocytoma associated with obstructive hydrocephalus and accompanied by 2 syringomyelic cavities in the cervicothoracic portion of the spinal cord. Immediately after gross total resection of the lesion, impaired mobility of the upper and lower extremities was observed, a finding that was not consistent with intraoperative neurophysiologic monitoring data. Hydrogen peroxide had been judiciously used to irrigate the resection tumor cavity. In the next few postoperative days, the patient suffered from transient diabetes insipidus and hyperpyrexia, indicative of hypothalamic injury. CONCLUSIONS Neurological evaluation of the patient, after stabilization of her medical condition, revealed residual spasticity of upper and lower extremities, rendering her able to mobilize via the aid of wheelchair only. The most possible pathophysiologic explanation of her neurological deterioration, including hypothalamic dysfunction, was analyzed. The role of hydrogen peroxide as a source of free radical formation, and its co-responsibility for vascular platelet aggregation and vasoconstriction was considered, upon case review, the main responsible etiologic factor.

Clinical, neuroimaging, and nerve conduction characteristics of spontaneous Conus Medullaris infarction

Background

Spontaneous conus medullaris infarction is a rare disease. We describe two patients with spontaneous conus medullaris infarction presenting as acute cauda equina syndrome and their unique electromyography (EMG) findings.

Case presentation

Two patients developed acute low back pain with mild asymmetric paraparesis, loss of perianal sensation and sphincter dysfunction. Ankle deep tendon reflexes were reduced in bilaterally. Neither patient had cardiovascular risk factors. Magnetic Resonance imaging showed infarction in the conus medullaris. Functional recovery was good in both patients, but progressive asymmetric calf wasting and sphincter dysfunction remained. EMG studies at follow-up of at least 3 years demonstrate active denervation at the muscles innervated by the first sacrum anterior horn cells.

Conclusion

Spontaneous conus medullaris infarction can occur in healthy individuals and presents as cauda equina syndrome. Findings of needle EMG studies indicate a progressive course of sacrum anterior horn cell disorder during long-term follow-up.

Prone versus sitting position in pediatric low-grade posterior fossa tumors

PURPOSE

The choice between sitting and prone position to access the infratentorial space in a suboccipital craniotomy is still a matter of debate. The comparisons in terms of complications and outcome of both positions are scarce, and the pediatric population is indeed more infrequent in these in scientific reviews. In this paper, we assess intraoperative and postoperative complications and neurological outcome in pediatric patients undergoing posterior cranial fossa surgery for pilocytic astrocytoma in sitting and prone position respectively.

METHODS

We retrospectively analyzed 30 consecutive patients undergoing surgery for cerebellar pilocytic astrocytoma at the two neurosurgical units referring to the University of Padova Medical School from 1999 to 2017. Preoperative, intraoperative, and postoperative data were retrieved from our medical archives.

RESULTS

The statistical analysis did not show any differences between the two groups in terms of preoperative, intraoperative, and postoperative data. The neurological status at last follow-up was similar in both groups of patients.

CONCLUSIONS

Our results suggest that both sitting and prone position can be considered safe in suboccipital craniotomies. Further studies are needed to show if there are possible differences between these positions for other frequent pediatric tumors such as medulloblastomas and ependymomas.

Acute tetraplegia following laryngotracheal reconstruction surgery

Background

Paraplegia following thoracic spinal surgery or abdominal operations is usually attributed to spinal cord ischemia due to interruption of the segmental spinal vascular supply. Alternatively, the etiology of spinal cord ischemia following cervical surgery is less clear.

Case Description

A 14-year-old male became acutely tetraplegic with a C4 sensory level and sphincteric dysfunction 12 h following surgery for tracheal stenosis due to prior intubation. Signs included loss of pain and temperature below the level of C4 with preservation of deep sensations (position and vibration) and mute plantar responses. The cervical magnetic resonance imaging revealed diffuse intramedullary cord swelling between C2-C7 and hyperintense signal changes in the anterior and posterior columns of the cord on T2-weighted images. Various etiologies for this finding included a cervical hyperextension or hyperflexion injury vs. anterior spinal artery syndrome.

Conclusions

Postoperative treatment of spinal cord ischemia attributed to cervical and thoracoabdominal surgery is largely ineffective in reversing major neurological deficits. Therefore, it is critical to prevent ischemia during these procedures by the avoidance of coagulopathies, anemia, hypotension, and hyperflexion/hyperextension maneuvers.

Paediatric spinal cord infarction-a review of the literature and two case reports

Ischemic spinal cord infarction is rare in the paediatric population, and when it does occur, it is usually associated with traumatic injury. Other potential causes include congenital cardiovascular malformations, cerebellar herniation, thromboembolic disease and infection. Magnetic resonance imaging (MRI) findings can be subtle in the early evaluation of such patients. The outcome is variable and depends on the level and extent of the spinal cord infarct and subsequent rehabilitation. Here, we present two cases of ischemic spinal cord infarction in children.

Spinal cord ischemia: aetiology, clinical syndromes and imaging features

INTRODUCTION

The purpose of this study was to analyse MR imaging features and lesion patterns as defined by compromised vascular territories, correlating them to different clinical syndromes and aetiological aspects.

METHODS

In a 19.8-year period, clinical records and magnetic resonance imaging (MRI) features of 55 consecutive patients suffering from spinal cord ischemia were evaluated.

RESULTS

Aetiologies of infarcts were arteriosclerosis of the aorta and vertebral arteries (23.6%), aortic surgery or interventional aneurysm repair (11%) and aortic and vertebral artery dissection (11%), and in 23.6%, aetiology remained unclear. Infarcts occurred in 38.2% at the cervical and thoracic level, respectively, and 49% of patients suffered from centromedullar syndrome caused by anterior spinal artery ischemia. MRI disclosed hyperintense pencil-like lesion pattern on T2WI in 98.2%, cord swelling in 40%, enhancement on post-contrast T1WI in 42.9% and always hyperintense signal on diffusion-weighted imaging (DWI) when acquired.

CONCLUSION

The most common clinical feature in spinal cord ischemia is a centromedullar syndrome, and in contrast to anterior spinal artery ischemia, infarcts in the posterior spinal artery territory are rare. The exclusively cervical location of the spinal sulcal artery syndrome seems to be a likely consequence of anterior spinal artery duplication which is observed preferentially here.

Non-traumatic spinal cord ischaemia in childhood - clinical manifestation, neuroimaging and outcome

BACKGROUND

Spinal cord ischaemia is rare in childhood and information on clinical presentation and outcome is scarce.

METHODS

This is a retrospective analysis of eight patients and 75 additional cases from the literature. Data search included: patient's age, primary manifestation, risk factors, neuroimaging and outcome.

RESULTS

Five female and three male patients gave consent to participate. Mean age was 12.5 years (10-15 years). Six patients presented with paraplegia; this was preceded by pain in four. Brown Sequard syndrome and quadriparesis were the two others' presenting condition. Sensation levels were thoracolumbar in seven cases. Bladder dysfunction only or bladder and bowel dysfunction were reported in eight and five patients respectively. Time to maximal symptom manifestation was <12 h in 7/8. Risk factors included surgery, minor trauma, recent infection, and thrombophilia. Mean follow-up was 3.3 years (0.25-6.3 years). Three patients remained wheelchair-dependent and three patients were ambulatory without aid. Bladder function recovered fully in five children. Most affected aspects of quality of life were physical and mental well-being and self-perception. T2-weighted-MR images showed pencil-like hyperintensity (8/8) in sagittal and H-shaped or snake-eyes-like lesion (6/8) in axial views. Analyses of all 83 patients were in congruence with the above results of the study group.

CONCLUSION

Spinal cord ischaemia in childhood presenting with pain, paraplegia, and bladder dysfunction has high morbidity concerning motor problems and quality of life. Acute arterial ischaemic event in children seems similar to adult events with respect to clinical presentation and, surprisingly, also in outcome.

[Controversies in neuroanaesthesia: positioning in neurosurgery]

Positioning of the neurosurgical patient has several features such as the existence of specific positions (i.e: sitting, prone hyperlordotic, crouching ou kneeling positions) or the range of facilities for the same surgical indications. The last point, a source of controversy, is the subject of this review. Current indications for the sitting position, positioning for lumbar spine surgery and prevention of eye injuries are successively addressed.

Zoologic companion animal rehabilitation and physical medicine

Injury and illness in zoologic companion animals can lead to significant pain and debilitation. Recovery can be slow and sometimes frustrating. By augmenting recovery from trauma or disease with physical medicine and rehabilitation techniques, recovery can be more rapid and complete. Physical medicine techniques, such as massage, can augment recovery from a painful injury or surgery by reducing edema, improving postoperative ileus, and decreasing anxiety. Familiarity with the tools of rehabilitation along with focus on pain management, strengthening, and proprioception improve patient care.