Edward S. Ahn and Edward R. Smith
✓Infratentorial and spinal subdural hematomas (SDHs) from traumatic injury in the pediatric population occur with such rarity that they can present the clinician with a challenge in diagnosis and management. When such hematomas are correctly identified, clinicians must decide whether to evacuate the lesion or manage it expectantly. The authors discuss the case of a 4-year-old child who presented with a clival and spinal SDH after a fall from a fourth-story window. The clinical and radiographic findings support a possible mechanism of evolution of these lesions. There is little evidence to guide management of clival and spinal SDHs. This case supports the evaluation for a spinal SDH when a clival hematoma is diagnosed. In the setting of a good neurological examination, expectant management can be an appropriate method of treatment. Additionally, this case lends insight into the pathophysiology of spinal SDHs. Unlike its intracranial counterpart, the spinal subdural space lacks bridging veins. The mechanism of formation of spinal SDHs after trauma has been heretofore relatively unclear. The images in this case support the hypothesis that redistribution of the clival SDH to dependent areas in the spinal subdural space is a significant mechanism in the evolution of these lesions.
Edward R. Smith and R. Michael Scott
Progression of vasculopathy associated with moyamoya syndrome is extremely variable. The authors review their experience in patients with unilateral moyamoya syndrome to identify factors predictive of contralateral clinical and imaging-documented disease progression.
The authors reviewed the clinical and imaging records of all patients with moyamoya syndrome and unilateral disease who underwent cerebral revascularization surgery between January 1985 and June 2006 by using a standardized surgical procedure, pial synangiosis.
Of 235 surgically treated patients with moyamoya syndrome, 33 (14%) presented with unilateral disease (4 adults and 29 children). There were 16 female and 17 male patients, with an average age of 10.4 years (26.8 years for adults and 8.1 years for children; range 1.5–39 years). Twenty patients presented with left-sided disease and 13 with right-sided disease.
The average follow-up after surgery was 5.3 years (3.1 years for adults and 5.6 years for children; range 1–16 years). During this period, 10 (30%) of 33 patients progressed to bilateral disease. The mean time until disease progression was 2.2 years (range 0.5–8.5 years). Factors associated with progression in this series included contralateral abnormalities on initial angiography, previous history of congenital cardiac anomaly, cranial irradiation, Asian ancestry, and familial moyamoya syndrome. Young age at diagnosis was associated with a more rapid rate of progression (age < 7 years, 0.9 years to progression and age ≥ 7 years, 3.1 years to progression).
Of patients with unilateral moyamoya syndrome, 30% will have progression of arteriopathy during long-term follow-up. In this series, the average time of progression from unilateral to bilateral angiographic disease was 2.2 years. Several factors, including contralateral abnormalities on initial imaging, congenital cardiac anomaly, previous cranial irradiation, Asian ancestry, and familial moyamoya syndrome, were associated with an increased risk of progression. Patients with known unilateral angiographic disease should undergo continued monitoring by using MR imaging and MR angiography at regular intervals. Treatment with pial synangiosis is safe and confers durable protection against stroke in patients with both bilateral and unilateral moyamoya syndrome.
Edward R. Smith and R. Michael Scott
Moyamoya is a progressive arteriopathy of unknown origin affecting the branches of the internal carotid artery (ICA). The arteriopathy can present as an isolated medical condition, affecting both sides of the brain (“moyamoya disease”) or can be unilateral or found in association with systemic disorders (“moyamoya syndrome”). The ischemia resulting from luminal narrowing predisposes children to transient ischemic attacks and stroke—the primary presentations of affected patients. Although it is rare—affecting 1 in 1 million children in the US—moyamoya is implicated in 6% of all childhood strokes. Diagnosis is defined by characteristic findings on arteriograms, including stenosis of the branches of the ICA and a pathognomonic spray of small collateral vessels in this region, descriptively likened to a “puff of smoke” (“moyamoya” in Japanese). Treatment is predicated on restoration of cerebral blood flow by surgical revascularization. The rarity of this disorder has limited research and the development of evidence-based clinical management. While acknowledging these limitations, in this article the authors aim to summarize current studies of pediatric moyamoya, with the objective of providing a framework for construction of evidence-based guidelines for treatment. The compilation of current data in these guidelines should serve as a resource to aid pediatric neurosurgeons in their role as advocates for providing appropriate care to affected children.
R. Michael Scott and Edward R. Smith
This issue of Neurosurgical Focus is devoted to the topic of moyamoya disease/syndrome. When the senior editor (R.M.S.) was a neurosurgical resident in the late 1960s and early 1970s, the condition was virtually unknown in the Western hemisphere, and patients with “cerebrovascular insufficiency” and the typical arterial findings on angiography were believed to have a type of arteritis. The refinement of catheter angiography techniques and the development of the imaging modalities of CT and MR imaging clarified the significance of making the correct diagnosis of moyamoya disease in affected patients, and with the development of direct and then indirect revascularization procedures during this same period, neurosurgeons became involved in the disease's treatment.
Bradley A. Gross, Edward R. Smith and R. Michael Scott
Cavernous malformations (CMs) of the basal ganglia are relatively rare lesions that can lead to considerable neurological impairment because of their eloquent location. The authors reviewed the clinical course and surgical outcome of a series of children with basal ganglia CMs.
The authors retrospectively reviewed the operative experience of the senior author (R.M.S.) and the 1997–2011 database of Boston Children's Hospital for children with CM of the basal ganglia (which includes CM of the caudate and/or lentiform nucleus and excludes CM of the thalamus). They evaluated baseline demographics, presenting signs, operative outcomes, and condition at long-term follow-up visits and compared these characteristics among patients who underwent surgery and those who were observed.
Of 180 children with a diagnosis of CM, 11 (6%) had CM of the basal ganglia. The mean age at diagnosis was 9.3 years, and the male/female ratio was 1.8:1. Presenting signs were as follows: hemorrhage (8 children), incidental lesions (2), and seizures (1); 2 children had choreiform movement disorders. Treatment was observation or surgery. Observation was chosen for 5 children either because the lesions were asymptomatic (2 children) or because the risk for neurological dysfunction after attempted excision was believed to be high (3 children). These 5 children were observed over a combined total of 30.4 patient-years; none experienced neurological deterioration or symptomatic hemorrhage from their lesions. The other 6 children underwent microsurgical resection of the lesion because they were symptomatic from hemorrhage or increasing mass effect. All 6 of these children had hemorrhagic lesions, of which the smallest dimension was at least 1.5 cm. Of these 6 lesions, 5 were excised completely, and over a combined total of 46 patient-years of follow-up, no rebleeding or late neurological deterioration after surgery was reported.
In this patient population, the natural history of small and asymptomatic CMs of the basal ganglia was benign. The children with large (> 1.5 cm) symptomatic lesions underwent excision; neurological impairment was apparently minimal, and no hemorrhage or neurological deterioration occurred later.
Patrick J. Codd, R. Michael Scott and Edward R. Smith
Seckel syndrome is an autosomal recessive disorder characterized by intrauterine and postnatal growth delay, microcephaly with mental retardation, and facial dysmorphisms including micrognathia, a recessed forehead, and a large beaked nose. Occurring in 1 in 10,000 children without sex preference, it is the most common primordial microcephalic osteodysplastic dwarfism and has been associated with a variety of congenital brain malformations and intracranial aneurysms. Moyamoya syndrome is an idiopathic, chronic, progressive cerebrovascular disorder marked by stenosis of the intracranial internal carotid arteries and concurrent development of hypertrophied collateral vessels. These tortuous arterial collaterals appear radiographically as “puffs of smoke,” giving the syndrome its name. In this report, the authors describe the case of a 16-year-old girl with coincident Seckel and moyamoya syndromes. To their knowledge, this is the first reported case of such an association being treated with surgical revascularization.
The patient presented with persistent headaches and a 2-year history of progressive hand, arm, and face numbness. Imaging studies revealed multiple completed cerebral infarcts, global ischemic changes, and vascular anatomy consistent with moyamoya syndrome. Bilateral pial synangioses successfully revascularized each hemisphere with resolution of the patient's symptoms. The patient died 1 year later of complications related to treatment of a rapidly progressing intracranial aneurysm.
This report documents the first case associating moyamoya and Seckel syndromes. In addition, the report reveals the rapid development of an intracranial aneurysm in a patient with this syndrome. When coupled with previous reports of other types of cerebrovascular disease in patients with Seckel syndrome or other primordial dwarfisms, the authors' findings are important because they suggest that physicians treating patients with dwarfism should consider the diagnosis of moyamoya syndrome when symptoms suggestive of cerebral ischemia are present. Prompt diagnosis and treatment of moyamoya syndrome, including the use of proven surgical revascularization procedures such as pial synangiosis, may significantly improve the long-term outcomes of these patients.
Edward R. Smith, William E. Butler and Fred G. Barker II
Object. Death after ventriculoperitoneal (VP) shunt surgery is uncommon, and therefore it has been difficult to study. The authors used a population-based national hospital discharge database to examine the relationship between annual hospital and surgeon volume of VP shunt surgery in pediatric patients and in-hospital mortality rates.
Methods. All children in the Nationwide Inpatient Sample (1998–2000, age 90 days—18 years) who underwent VP shunt placement or shunt revision as the principal procedure were included. Main outcome measures were in-hospital mortality rates, length of stay (LOS), and total hospital charges.
Overall, 5955 admissions were analyzed (253 hospitals, 411 surgeons). Mortality rates were lower at high-volume centers and for high-volume surgeons. In terms of hospital volume, the mortality rate was 0.8% at lowest-quartile-volume centers (< 28 admissions/year) and 0.3% at highest-quartile-volume centers (> 121 admissions/year). In terms of surgeon volume, the mortality rate was 0.8% for lowest-quartile-volume providers (< nine admissions/year) and 0.1% for highest-quartile-volume providers (> 65 admissions/year). After multivariate adjustment for demographic variables, emergency admission and presence of infection, hospital volume of care remained a significant predictor of death (odds ratio [OR] for a 10-fold increase in caseload 0.38; 95% confidence interval [CI] 0.18–0.81). Surgeon volume of care was statistically significant in a similar multivariate model (OR for a 10-fold increase in caseload 0.3; 95% CI 0.13–0.69). Length of stay was slightly shorter and total hospital charges were slightly higher at higher-volume centers, but the differences were not statistically significant.
Conclusions. Pediatric shunt procedures performed at high-volume hospitals or by high-volume surgeons were associated with lower in-hospital mortality rates, with no significant difference in LOS or hospital charges.
Edward R. Smith, William E. Butler and Fred G. Barker II
Concern for patient safety, among other reasons, recently prompted sweeping changes in resident work policies in the US. Some have speculated that the arrival of new interns and residents at teaching hospitals each July might cause an annual transient increase in poor patient outcomes and inefficient care.
Data were analyzed for 4323 craniotomies for tumor resection and 22,072 shunt operations performed in pediatric patients between 1988 and 2000 in US nonfederal hospitals (Nationwide Inpatient Sample, Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality, Rockville, MD). In-hospital mortality rates, discharge outcome, complications, and efficiency measures (length of stay [LOS] and hospital charges) for patients treated in July and August were compared with similar data for patients in other months.
There were no significant increases in any adverse end point for either tumor or shunt operations in July and August. Odds ratios (95% confidence interval [CI]) for outcome of tumor craniotomies performed in July and August compared with outcome for tumor craniotomies performed in other months were as follows: for mortality rate, 0.43 (0.14–1.32); for adverse discharge disposition, 1.03 (0.71–1.51); for neurological complications, 1.00 (0.63–1.59); for transfusion, 0.70 (0.41–1.19). Hospital charges were 0.5% lower (range −6 to 5%) in July and August, and LOS was 3% shorter (range −8 to 3%). Odds ratios (95% CI) for July or August shunt surgery compared with shunt surgery performed in other months were as follows: for mortality rate, 0.96 (0.58–1.60); for adverse discharge disposition, 0.85 (0.66–1.11); for neurological complications, 1.27 (0.75–2.16); for transfusion, 0.81 (0.48–1.37). Hospital charges were 0.2% higher in July and August (range −3 to 3%), and LOS was 3% shorter (range −5 to 0.5%).
Although moderate increases in some adverse end points could not be excluded, there was no evidence that brain tumor or shunt surgery performed in pediatric patients at US teaching hospitals during July and August is associated with more frequent adverse patient outcome or inefficient care than similar surgery performed during other months.