Pediatric cerebellar infarction caused by atlantoaxial subluxation--case report

Vertebral Artery Dissection in the Setting of Unstable Os Odontoideum: A Case Report

CASE

A healthy 5-year-old boy presented with a gradual onset of headaches and acute global right-sided weakness over 10 days. The work-up revealed unstable os odontoideum leading to multiple posterior circulation infarcts with vertebral artery dissection. He underwent antiplatelet therapy, cervical collar immobilization, and delayed occiput to C2 posterior spinal fusion and instrumentation with iliac crest autograft. At 2-year follow-up, the patient had a solid fusion mass, appropriate cervical alignment, and was without neurologic sequelae.

CONCLUSION

This case adds to a sparse body of literature in the management of vertebral artery dissection with vertebrobasilar insufficiency secondary to unstable os odontoideum.

Decompressive hemicraniectomy in pediatric malignant arterial ischemic stroke: a case-based review

PURPOSE

Malignant stroke is a life-threatening emergency, with a high mortality rate (1-3). Despite strong evidence showing decreased morbidity and mortality in the adult population, decompressive hemicraniectomy (DCH) has been scarcely reported in the pediatric stroke population, and its indication remains controversial, while it could be a potential lifesaving option.

METHODS AND RESULTS

We performed an extensive literature review on pediatric malignant arterial ischemic stroke (pmAIS) and selected 26 articles reporting 97 cases. Gathering the data together, a 67% mortality rate is observed without decompressive therapy, contrasting with a 95.4% survival rate with it. The median modified Rankin score (mRS) is 2.1 after surgery with a mean follow-up of 31.8 months. For the 33% of children who survived without surgery, the mRS is 3 at a mean follow-up of 19 months. As an illustrative case, we report on a 2-year-old girl who presented a cardioembolic right middle cerebral artery stroke with subsequent malignant edema and ongoing cerebral transtentorial herniation in the course of a severe myocarditis requiring ECMO support. A DCH was done 32 h after symptom onset. At the age of 5 years, she exhibits an mRS of 3.

CONCLUSION

Pediatric stroke with malignant edema is a severe condition with high mortality rate if left untreated and often long-lasting consequences. DCH might minimize the vicious circle of cerebral swelling, increasing intracranial pressure and brain ischemia. Our literature review underscores DCH as an efficient therapeutic measure management of pmAIS even when performed after a significant delay; however, long-lasting morbidities remain high.

Posterior Circulation Stroke due to Atlantoaxial Instability in CHST3-Related Skeletal Dysplasia: A Case Report

CASE

An eight-year-old boy presented with acute encephalopathy due to posterior circulation ischemic stroke. He was found to have vertebral artery stenosis secondary to atlantoaxial instability (AAI) due to an os odontoideum. Occipitocervical fusion was performed 4 weeks after stroke. The child improved neurologically and regained independent ambulation. He had indications of an underlying spondyloepiphyseal dysplasia with joint luxation and whole-exome sequencing diagnosed CHST3-related skeletal dysplasia.

CONCLUSION

As far as we know, this AAI due to an os odontoideum is a previously unreported complication of CHST3-related skeletal dysplasia. Occipitocervical fusion yielded good clinical results with the 1-year follow-up.

Profiles of Vertebral Artery Dissection with Congenital Craniovertebral Junction Malformation: Four New Cases and a Literature Review

OBJECTIVE

Vertebral artery dissection (VAD) combined with congenital craniovertebral junction malformation (CVJM) is rare. This study aimed to analyze the etiology, clinical and imaging features, treatment, and prognosis of VAD with CVJM.

METHODS

Four new cases of VAD with congenital CVJM and 28 similar cases found in the literature were included. Detailed clinical data from all cases were retrospectively analyzed.

RESULTS

A total of 32 patients (28 men, four women; mean age 19.01±12.53 years) were included. Seventeen of 32 cases (53.1%) had had multiple ischemic episodes. The most common neurological symptoms were limb numbness/weakness (20/32), ataxia (15/32), and dizziness/vertigo (12/32). In sum, 31 of 32 cases had multiple infarcts scattered throughout the posterior circulation area on cranial computed tomography or resonance imaging. Dissection had occurred in the V3 segment of the VA in 29/31 cases (93.5%). The most common congenital CVJMs were atlantoaxial dislocation and atlantoaxial subluxation (found in 20/32 cases [62.5%]), while 27/32 cases (84.3%) had multiple combined abnormalities. Seven of eleven cases (63.6%) with initial antiplatelet treatment and one of eleven (9.1%) with initial anticoagulation treatment experienced stoke recurrence. Fusion or vertebral fixation was performed in 16 patients and aneurysm resection in one patient. There was no reported recurrence after surgery in 13 patients with follow-up data.

CONCLUSION

Underlying CVJM is a rare but overlooked etiology in VAD, and is prone to induce recurrent ischemic stroke. Patients with VAD, especially that localized in the V3 segment, should be examined for CVJM. Timely assessment is critical for determining the specific cause and to provide targeted intervention.

Decompressive craniectomy for acute ischemic stroke

Malignant stroke occurs in a subgroup of patients suffering from ischemic cerebral infarction and is characterized by neurological deterioration due to progressive edema, raised intracranial pressure, and cerebral herniation. Decompressive craniectomy (DC) is a surgical technique aiming to open the “closed box” represented by the non-expandable skull in cases of refractory intracranial hypertension. It is a valuable modality in the armamentarium to treat patients with malignant stroke: the life-saving effect has been proven for both supratentorial and infratentorial DC in virtually all age groups. This leaves physicians with the difficult task to decide who will require early or preemptive surgery and who might benefit from postponing surgery until clear evidence of deterioration evolves. Together with the patient’s relatives, physicians also have to ascertain whether the patient will have acceptable disability and quality of life in his or her presumed perception, based on preoperative predictions. This complex decision-making process can only be managed with interdisciplinary efforts and should be supported by continued research in the age of personalized medicine.

Imaging of the craniovertebral junction anomalies in children

The craniovertebral junction (CVJ) is interposed between the unsegmented skull and the segmented spine; it is functionally unique as it allows the complex motion of the head. Because of its unique anatomy, numerous craniometric indices have been devised. Because of its complex embryology, different from that of the adjacent skull and spine, it is commonly the seat of malformations. Because of the mobility of the head, and its relative weight, the craniovertebral junction is vulnerable to trauma. Like the rest of the axial skeleton, it may be affected by many varieties of dysplasia. In addition, the bony craniovertebral junction contains the neural craniovertebral junction and its surrounding CSF: any bony instability or loss of the normal anatomic relationships may therefore compromise the neural axis. In addition, the obstruction of the meningeal spaces at this level can compromise the normal dynamics of the CSF and result in hydrocephalus and/or syringohydromyelia. To image the CVJ, plain X-rays are essentially useless. MR is optimal in depicting the soft tissues (including the neural axis) and the joints, as well as the bone itself. CT still may be important to better demonstrate the bony abnormalities.

Space-occupying cerebellar infarction: complications, treatment, and outcome

Space-occupying brain edema is a frequent and one of the most dreaded complications in ischemic cerebellar stroke. Because the tight posterior fossa provides little compensating space, any space-occupying lesion can lead to life-threatening complications through brainstem compression or compression of the fourth ventricle and subsequent hydrocephalus, both of which may portend transtentorial/transforaminal herniation. Patients with large cerebellar infarcts should be treated and monitored very early on in an experienced stroke unit or (neuro)intensive care unit. The general treatment of ischemic cerebellar infarction does not differ from that of supratentorial ischemic strokes. Treatment strategies for space-occupying edema include pharmacological antiedema and intracranial pressure–lowering therapies, ventricular drainage by means of an extraventricular drain, and suboccipital decompressive surgery, with or without resection of necrotic tissue. Timely escalation of treatment is crucial and should be guided by clinical and neuroradiological rationales. Patients in a coma after hydrocephalus and/or local brainstem compression may also benefit from more aggressive surgical treatment, as long as the conditions are reversible. Contrary to the general belief that outcome in survivors of space-occupying cerebellar stroke is usually good, recent studies suggest that for many of these patients, the long-term outcome is not good. In particular, advanced age and additional brainstem infarction seem to be predictors for poor outcome. Further trials are necessary to investigate these findings systematically and provide better selection criteria to help guide decisions about surgical therapies, which should always be carried out in close cooperation among neurointensive care physicians, neurologists, and neurosurgeons.

Decompressive craniectomy in childhood posterior circulation stroke: a case series and review of the literature

Few reports address the role of decompressive craniectomy in children with space-occupying cerebral edema attributable to severe ischemic infarction of the posterior cerebral arterial circulation. We describe four children with posterior circulation arterial ischemic stroke who required decompressive craniectomy. These children accounted for 11% of all cases of posterior circulation ischemic stroke at our institution from 2002-2010. Three manifested large, cerebellar hemispheric infarcts, and one manifested a large, temporo-occipital posterior cerebral artery infarct. Deterioration occurred within 72 hours of stroke onset. Two patients demonstrated minimal functional deficits at follow-up, and two demonstrated moderate deficits with functional limitations. Because decompressive craniectomy can be lifesaving in children with severe posterior circulation arterial ischemic stroke, early neurosurgical referral should be considered.

Distinctive tomographic features of atlantoaxial dislocation in a boy with acromesomelic dysplasia du Pan syndrome

Distinctive tomographic features of atlantoaxial dislocation have been encountered in a child with du Pan syndrome. Three-dimensional computed tomography scan showed agenesis of the odontoid process associated with significant hypoplasia of the left lateral mass of the odontoid. Bidirectional fluorescent DNA sequencing have been used to identify mutations in the complete coding region (exon 1-2) of the cartilage-derived morphogenic protein 1 gene. No mutation was detected in the analysed region. We report what might be a novel variant of acromesomelic du Pan syndrome.

Multiple cerebellar hemorrhagic infarctions following surgery for a huge atlantoaxial neurinoma

BACKGROUND CONTEXT

There have been only five reported cases with cerebellar hemorrhagic infarction after spinal surgery, and the underlying pathomechanism remains obscure.

PURPOSE

To describe a case with multiple cerebellar hemorrhagic infarctions after surgery for a huge atlantoaxial neurinoma.

STUDY DESIGN/SETTING

Case report

METHODS

A 36-year-old man underwent uneventful surgery for a huge atlantoaxial neurinoma. After surgery, the patient was lethargic with slurred speech and subsequently developed cerebellar symptoms, although preoperative myelopathic symptoms did not worsen. The clinical and radiological findings are presented, and possible causes of the hemorrhages are discussed.

RESULTS

Magnetic resonance imaging of the brain after surgery showed multiple cerebellar hemorrhagic infarctions. However, magnetic resonance angiography revealed no occlusion or stenosis in the vertebrobasilar system, and a duplex scan of the neck vessels confirmed normal flow in the vertebral arteries after surgery. In response to the conservative treatment, the patient exhibited neurological recovery with disappearance of cerebellar symptoms.

CONCLUSIONS

In the present case with multiple cerebellar hemorrhagic infarctions, venous infarction appears more likely to be the cause of cerebellar hemorrhagic infarction than arterial infarction. The most likely underlying pathomechanism is a cerebellar venous disturbance precipitated by loss of a large amount of cerebrospinal fluid, although the exact etiology remains elusive.

Cerebellar infarction secondary to os odontoideum

A 43-year-old man developed cerebellar infarction due to atlantoaxial dislocation associated with os odontoideum. Cervical X-ray films confirmed os odontoideum, and conventional angiography revealed irregular narrowing of the right vertebral artery at the axis level. A correlation between the vertebral artery lesion and atlantoaxial instability was shown with 3-dimensional (3-D) computed tomographic (CT) angiography. This is the first case of atlantoaxial dislocation with vertebral artery stenosis demonstrated 3-D CT angiography. 3-D CT angiography can support the conventional angiography with respect to the diagnosis and management of vertebral artery insufficiency associated with occipitocervical deformity.

Os odontoideum with cerebellar infarction: a case report

STUDY DESIGN

A case report.

OBJECTIVES

To report the case of a child with os odontoideum associated with cerebellar infarction and to discuss the correlation between atlantoaxial instability with os odontoideum and vertebrobasilar artery insufficiency.

SUMMARY OF BACKGROUND DATA

Knowledge of the influence of atlantoaxial instability on vertebrobasilar artery insufficiency remains limited despite the publication of several reports.

METHODS

A 5-year-old boy with ataxic gait disturbance was hospitalized in the pediatric ward. Magnetic resonance imaging revealed multiple cerebellar infarctions, and cerebral angiogram showed occlusions of several branches of the basilar artery and a winding of the left vertebral artery. Stress lateral radiographs of the cervical spine showed atlantoaxial instability with os odontoideum. Posterior C1-C2 transarticular screw fixation with iliac bone graft was applied to obtain firm stability and fusion.

RESULTS

There was no damage to the vertebral arteries or spinal nerves in the perioperative period. Solid union of the grafted bone and rigid stability of the atlantoaxial joint were seen on lateral flexion-extension radiographs 1 year after the operation. There has been no sign of recurrent arterial insufficiency, and the patient has been free from cerebellar dysfunction to date.

CONCLUSIONS

Atlantoaxial instability may cause insufficiency of the vertebral artery as well as spinal cord injury. More attention should be paid to the possible relation between atlantoaxial instability and vertebrobasilar artery insufficiency.

Complete reduction of retro-odontoid soft tissue mass in os odontoideum following the posterior C1-C2 tranarticular screw fixation

STUDY DESIGN

A case report of os odontoideum with retro-odontoid soft tissue hypertrophy treated by the transarticular screw fixation.

OBJECTIVES

To present a case of os odontoideum that showed complete reduction of retro-odontoid soft tissue mass caused by atlantoaxial subluxation after the C1-C2 transarticular screw fixation.

SUMMARY OF BACKGROUND DATA

Hypertrophy of the periodontoid soft tissue has been reported to be associated with chronic atlantoaxial subluxation and progressive myelopathy. While the rheumatoid pannus has been reported to become reduced of disappear after fixation of the unstable segment, the reduction of the hypertrophied soft tissue mass has never been reported in atlantoaxial subluxation of nonrheumatoid origin, especially in the case of os odontoideum.

METHODS

Posterior C1-C2 transarticular screw fixation was performed in a patient with os odontoideum, who showed signs of progressive myelopathy by the compression of retro-odontoid soft tissue mass and atlantoaxial subluxation.

RESULTS

The fixation of atlantoaxial subluxation achieved not only the complete reduction of the retro-odontoid soft tissue mass, but also clinical improvement of the myelopathy.

CONCLUSIONS

Posterior atlantoaxial fixation is worth trying in slow progressing myelopathy by the compression of hypertrophy of the soft tissue even in nonrheumatoid atlantoaxial subluxation, thereby obviating the need for direct removal of the mass via the transoral route.