Eric Laurent, Irvin Sam Schonfeld and Renzo Bianchi
Christopher J. Stapleton, Martin H. Pham, Frank J. Attenello and Patrick C. Hsieh
Ossification of the posterior longitudinal ligament (OPLL) is a disease of progressive ectopic calcification of the PLL of the spine. It occurs most frequently in the cervical spine, followed by the thoracic spine. The disease was first described in the Japanese population, and the prevalence of OPLL is highest in Japan at a rate of 1.9%–4.3%. Note, however, that OPLL is also seen and is a known cause of cervical myelopathy in other Asian countries and in the white population. Research into the underlying cause of OPLL over the past few decades has shown that it is a multifactorial disease with significant genetic involvement. Genetic studies of OPLL have revealed several gene loci that may be involved in the pathogenesis of this disease. Genes encoding for proteins that process extracellular inorganic phosphate, collagen fibrils, and transcription factors involved in osteoblast and chondrocyte development and differentiation have all been implicated in the pathophysiology of OPLL. In this paper, the authors review current understanding of the genetics and pathophysiology of OPLL.
Matthew J. McGirt, Frank J. Attenello, Daniel M. Sciubba, Ziya L. Gokaslan and Jean-Paul Wolinsky
✓ Pediatric basilar invagination and cranial settling have traditionally been approached through a transoral–transpharyngeal route with or without extended maxillotomy or mandibulotomy for resection of the anterior portion of C-1 and the odontoid. The authors hypothesize that application of a recently described endoscopic transcervical odontoidectomy (ETO) technique would allow an alternative approach for the treatment of ventral pathological entities at the craniocervical junction in pediatric patients.
The authors performed ETO in a consecutive series of pediatric patients presenting with myelopathy or bulbar dysfunction resulting from basilar invagination or cranial settling. All clinical, radiographic, surgical, and follow-up data were prospectively collected. The initial experience with ETO in the pediatric population is analyzed and outcomes are reported. Three patients required ETO for basilar invagination and 1 required ETO with anterior C-1 arch and distal clivus resection for cranial settling. All patients presented with myelopathy. One patient was wheelchair bound with severe quadriparesis. The mean age was 14 ± 3 years (mean ± standard deviation [SD]) in the 2 male and 2 female patients. The ETO and posterior fusion were performed as a 2-stage procedure in 2 (50%) and as a single-stage procedure in 2 (50%) cases. Prolonged intubation or postoperative placement of a gastrostomy tube was not needed in any case. The postoperative hospitalization lasted 9 ± 4 days (mean ± SD). At last follow-up (mean 5 months), head and neck pain had resolved and motor strength had improved or stabilized in all cases. All 4 children were independently functioning and ambulatory at the last follow-up.
In the authors' initial experience, ETO has allowed ventral brainstem decompression without the need for prolonged intubation, worsening dysphagia requiring enteral tube feeding, or prolonged hospitalization, and has resulted in cosmetically appealing results. The ETO technique allows an alternative approach for the treatment of ventral pathological entities at the craniocervical junction in pediatric patients.
Eisha A. Christian, Diana L. Jin, Frank Attenello, Timothy Wen, Steven Cen, William J. Mack, Mark D. Krieger and J. Gordon McComb
Even with improved prenatal and neonatal care, intraventricular hemorrhage (IVH) occurs in approximately 25%–30% of preterm infants, with a subset of these patients developing hydrocephalus. This study was undertaken to describe current trends in hospitalization of preterm infants with posthemorrhagic hydrocephalus (PHH) using the Nationwide Inpatient Sample (NIS) and the Kids’ Inpatient Database (KID).
The KID and NIS were combined to generate data for the years 2000–2010. All neonatal discharges with ICD-9-CM codes for preterm birth with IVH alone or with IVH and hydrocephalus were included.
There were 147,823 preterm neonates with IVH, and 9% of this group developed hydrocephalus during the same admission. Of patients with Grade 3 and 4 IVH, 25% and 28%, respectively, developed hydrocephalus in comparison with 1% and 4% of patients with Grade 1 and 2 IVH, respectively. Thirty-eight percent of patients with PHH had permanent ventricular shunts inserted. Mortality rates were 4%, 10%, 18%, and 40%, respectively, for Grade 1, 2, 3, and 4 IVH during initial hospitalization. Length of stay has been trending upward for both groups of IVH (49 days in 2000, 56 days in 2010) and PHH (59 days in 2000, 70 days in 2010). The average hospital cost per patient (adjusted for inflation) has also increased, from $201,578 to $353,554 (for IVH) and $260,077 to $495,697 (for PHH) over 11 years.
The number of neonates admitted with IVH has increased despite a decrease in the number of preterm births. Rates of hydrocephalus and mortality correlated closely with IVH grade. The incidence of hydrocephalus in preterm infants with IVH remained stable between 8% and 10%. Over an 11-year period, there was a progressive increase in hospital cost and length of stay for preterm neonates with IVH and PHH that may be explained by a concurrent increase in the proportion of patients with congenital cardiac anomalies.
Martin H. Pham, Frank J. Attenello, Joshua Lucas, Shuhan He, Christopher J. Stapleton and Patrick C. Hsieh
Ossification of the posterior longitudinal ligament (OPLL) can result in significant myelopathy. Surgical treatment for OPLL has been extensively documented in the literature, but less data exist on conservative management of this condition.
The authors conducted a systematic review to identify all reported cases of OPLL that were conservatively managed without surgery.
The review yielded 11 published studies reporting on a total of 480 patients (range per study 1–359 patients) over a mean follow-up period of 14.6 years (range 0.4–26 years). Of these 480 patients, 348 (72.5%) were without myelopathy on initial presentation, whereas 76 patients (15.8%) had signs of myelopathy; in 56 cases (15.8%), the presence of myelopathy was not specified. The mean aggregate Japanese Orthopaedic Association score on presentation for 111 patients was 15.3. Data available for 330 patients who initially presented without myelopathy showed progression to myelopathy in 55 (16.7%), whereas the other 275 (83.3%) remained progression free. In the 76 patients presenting with myelopathy, 37 (48.7%) showed clinical progression, whereas 39 (51.5%) remained clinically unchanged or improved.
Patients who present without myelopathy have a high chance of remaining progression free. Those who already have signs of myelopathy at presentation may benefit from surgery due to a higher rate of progression over continued follow-up.
Frank J. Attenello, Matthew J. McGirt, April Atiba, Muraya Gathinji, Ghazala Datoo, Jon Weingart, Benjamin Carson and George I. Jallo
Chiari malformation Type I (CM-I) is often associated with scoliosis. It remains unclear which subgroups of patients are most likely to experience progression of spinal deformity after cervicomedullary decompression. The authors' goal was to determine the time frame of curvature progression and assess which patient subgroups are at greatest risk for progression of spinal deformity after surgery.
The authors retrospectively reviewed the records of all pediatric patients with significant scoliosis in whom suboccipital decompression was performed to treat for CM-I during a 10-year period at a single academic institution. Clinical, radiological, and operative variables were assessed as independent factors for failure (worsening of scoliosis) by using a univariate regression analysis.
Twenty-one children (mean age 9 ± 3 years; 4 male) underwent hindbrain decompression for CM-I–associated scoliosis and were followed for a mean of 39 months. All patients harbored a syrinx. Eight patients (38%) experienced improvement in scoliosis curvature, whereas 10 (48%) suffered a progression. Thoracolumbar junction scoliosis (p = 0.04) and failure of the syrinx to improve (p = 0.05) were associated with 5- and 4-fold respective increases in the likelihood of deformity progression. Each increasing degree of preoperative Cobb angle was associated with an 11% increase in the likelihood of scoliotic curve progression (p < 0.05).
Over one third of patients with CM-I–associated scoliosis will improve after cervicomedullary decompression alone. Cervicomedullary decompression is a good first-line option, particularly in children with concordant posterior fossa symptoms. Patients presenting with more severe scoliosis (increasing Cobb angle) or scoliosis that crosses the thoracolumbar junction may benefit from earlier orthopedic involvement and should be monitored regularly for curvature progression after cervicomedullary decompression. In cases in which there is a failure of the syrinx to show improvement after suboccipital decompression, the patients are also more likely to develop curvature progression.
Matthew J. McGirt, Kaisorn L. Chaichana, April Atiba, Frank Attenello, Kevin C. Yao and George I. Jallo
With modern surgical advances, radical resection of pediatric intramedullary spinal cord tumors (IMSCTs) can be expected to preserve long-term neurological function. Nevertheless, postoperative neurological decline is not uncommon after surgery, and many patients continue to experience long-term dysesthetic symptoms. Preoperative predictors of postoperative neurological decline and sensory syndromes have not been investigated and may serve as a guide for surgical risk stratification.
Neurological function (as determined using the modified McCormick Scale [mMS]) preoperatively, postoperatively, and 3 months after surgery was retrospectively recorded from patient charts in 164 consecutive patients undergoing resection of IMSCTs. A median 4 years (interquartile range [IQR] 1–8 years) after surgery, long-term motor and sensory symptoms were assessed by telephone interviews and corroborated by subsequent medical visits in 120 available patients. This long-term assessment was retrospectively reviewed for the purposes of this study. The authors reviewed this series to assess long-term motor, sensory, and urinary outcomes and to determine independent risk factors of postoperative neurological decline and long-term sensory dysfunction.
Patients were 8.6 ± 5.7 years old and presented with a median mMS of 2 (IQR 2–4). Three months after surgery, 38 patients (23%) continued to experience decreased neurological function (1 mMS point) incurred perioperatively. Increasing age (p = 0.028), unilateral symptoms (p = 0.046), and urinary dysfunction at presentation (p = 0.004) independently predicted persistent 3-month perioperative decline. At long-term follow-up (median 4 years), 39 (33%) exhibited improvements in their mMS scores, 13 (30%) had improvement in their urinary dysfunction, and 27 (30%) had resolution of their dysesthesias. Seventy-eight patients (65%) experienced long-term dysesthetic symptoms. Increasing age (p = 0.024), preoperative symptom duration > 12 months (p = 0.027), and worsened postoperative mMS score at hospital discharge (p = 0.013) independently increased the risk of long-term dysesthesias.
In the authors' experience, nearly one third of patients may experience improvement in motor, sensory, and urinary dysfunction years after IMSCT resection, whereas the majority will continue to experience long-term dysesthetic symptoms. Improvement in motor deficits preceded improvement in sensory syndromes, and urinary dysfunction typically resolved much longer after surgery. The risk of persistent perioperative motor decline was increased with older age, unilateral symptoms, preoperative urinary symptoms, and less severe preoperative neurological deficit. The risk of long-term dysesthesias was increased with older age, increased duration of symptoms prior to resection, and greater postoperative neurological deficit.
Matthew J. McGirt, Frank J. Attenello, Ghazala Datoo, Muraya Gathinji, April Atiba, Jon D. Weingart, Benjamin Carson and George I. Jallo
Indications for duraplasty in treatment of Chiari malformation Type I (CM-I) remain unclear. In the present study, the authors evaluate their surgical experience to determine whether intraoperative ultrasonography is effective in the selection of patients with CM-I who can be adequately treated with craniectomy alone without duraplasty.
The authors reviewed the records of 256 children who underwent first-time hindbrain decompression for CM-I. Craniectomy alone (without duraplasty) was performed when intraoperative ultrasonography suggested adequate decompression of the subarachnoid spaces ventral and dorsal to the tonsils after suboccipital craniectomy alone. Duraplasty was performed if intraoperative ultrasonography demonstrated persistent dural compression of the tonsils following craniectomy. Symptom recurrence as a function of time was compared between cases of duraplasty versus suboccipital decompression alone stratified by extent of tonsillar herniation.
Duraplasty was performed in 140 patients (55%), and suboccipital decompression alone was performed in 116 patients (45%). Patients underwent follow-up for 29 ± 15 months. Symptoms included headache in 192 patients (75%) and lower cranial nerve and brainstem dysfunction in 68 (27%). In 38 patients (15%) there was tonsillar herniation rostral to the C-1 lamina, in 195 (76%) it extended between the C-1 and C-2 lamina, and in 23 patients (9%) there was herniation caudal to the lower border of the C-2 lamina. In children with tonsillar herniation caudal to C-1, ultrasonography-guided suboccipital decompression alone was associated with a 2-fold increase in the risk of symptom recurrence compared with those who also underwent duraplasty (p = 0.01). In children with tonsillar herniation rostral to C-1, outcome was equivalent between suboccipital decompression alone and duraplasty (p = 0.41).
In the setting of moderate-to-severe tonsillar CM-I, intraoperative ultrasonography demonstrating decompression of the subarachnoid spaces ventral and dorsal to the tonsils may not effectively select patients in whom bone decompression alone is sufficient. Duraplasty may be warranted in cases of tonsillar herniation that extends below the C-1 lamina regardless of intraoperative ultrasonography findings. More objective cerebrospinal fluid flow or volumetric measures may be needed intraoperatively to guide duraplasty in patients with more pronounced tonsillar herniation.
Matthew J. McGirt, Kaisorn L. Chaichana, Muraya Gathinji, Frank J. Attenello, Khoi Than, Alessandro Olivi, Jon D. Weingart, Henry Brem and Alf redo Quiñones-Hinojosa
With recent advances in the adjuvant treatment of malignant brain astrocytomas, it is increasingly debated whether extent of resection affects survival. In this study, the authors investigate this issue after primary and revision resection of these lesions.
The authors retrospectively reviewed the cases of 1215 patients who underwent surgery for malignant brain astrocytomas (World Health Organization [WHO] Grade III or IV) at a single institution from 1996 to 2006. Patients with deep-seated or unresectable lesions were excluded. Based on MR imaging results obtained < 48 hours after surgery, gross-total resection (GTR) was defined as no residual enhancement, near-total resection (NTR) as having thin rim enhancement of the resection cavity only, and subtotal resection (STR) as having residual nodular enhancement. The independent association of extent of resection and subsequent survival was assessed via a multivariate proportional hazards regression analysis.
Magnetic resonance imaging studies were available for review in 949 cases. The mean age and mean Karnofsky Performance Scale (KPS) score at time of surgery were 51 ± 16 years and 80 ± 10, respectively. Surgery consisted of primary resection in 549 patients (58%) and revision resection for tumor recurrence in 400 patients (42%). The lesion was WHO Grade IV in 700 patients (74%) and Grade III in 249 (26%); there were 167 astrocytomas and 82 mixed oligoastrocytoma. Among patients who underwent resection, GTR, NTR, and STR were achieved in 330 (35%), 388 (41%), and 231 cases (24%), respectively. Adjusting for factors associated with survival (for example, age, KPS score, Gliadel and/or temozolomide use, and subsequent resection), GTR versus NTR (p < 0.05) and NTR versus STR (p < 0.05) were independently associated with improved survival after both primary and revision resection of glioblastoma multiforme (GBM). For primary GBM resection, the median survival after GTR, NTR, and STR was 13, 11, and 8 months, respectively. After revision resection, the median survival after GTR, NTR, and STR was 11, 9, and 5 months, respectively. Adjusting for factors associated with survival for WHO Grade III astrocytoma (age, KPS score, and revision resection), GTR versus STR (p < 0.05) was associated with improved survival. Gross-total resection versus NTR was not associated with an independent survival benefit in patients with WHO Grade III astrocytomas. The median survival after primary resection of WHO Grade III (mixed oligoastrocytomas excluded) for GTR, NTR, and STR was 58, 46, and 34 months, respectively.
In the authors' experience with both primary and secondary resection of malignant brain astrocytomas, increasing extent of resection was associated with improved survival independent of age, degree of disability, WHO grade, or subsequent treatment modalities used. The maximum extent of resection should be safely attempted while minimizing the risk of surgically induced neurological injury.
Casey A. Jarvis, Joshua Bakhsheshian, Li Ding, Timothy Wen, Austin M. Tang, Edith Yuan, Steven L. Giannotta, William J. Mack and Frank J. Attenello
Fragmentation of care following craniotomy for tumor resection is increasingly common with the regionalization of neurosurgery. Hospital readmission to a hospital (non-index) other than the one from which patients received their original care (index) has been associated with increases in both morbidity and mortality for cancer patients. The impact of non-index readmission after surgical management of brain tumors has not previously been evaluated. The authors set out to determine rates of non-index readmission following craniotomy for tumor resection and evaluated outcomes following index and non-index readmissions.
Retrospective analyses of data from cases involving resection of a primary brain tumor were conducted using data from the Nationwide Readmissions Database (NRD) for 2010–2014. Multivariate logistic regression was used to evaluate the independent association of patient and hospital factors with readmission to an index versus non-index hospital. Further analysis evaluated association of non-index versus index hospital readmission with mortality and major complications during readmission. Effects of readmission hospital procedure volume on mortality and morbidity were evaluated in post hoc analysis.
In a total of 17,459 unplanned readmissions, 84.4% patients were readmitted to index hospitals and 15.6% to non-index hospitals. Patient factors associated with increased likelihood of non-index readmission included older age (75+: OR 1.44, 95% CI 1.19–1.75), elective index admission (OR 1.19, 95% CI 1.08–1.30), increased Elixhauser comorbidity score ≥2 (OR 1.18, 95% CI 1.01–1.37), and malignant tumor diagnosis (OR 1.32, 95% CI 1.19–1.45) (all p < 0.04). Readmission to a non-index facility was associated with a 28% increase in major complications (OR 1.28, 95% CI 1.14–1.43, p < 0.001) and 21% increase in mortality (OR 1.21, 95% CI 1.02–1.44, p = 0.032) in initial analysis. Following a second multivariable logistic regression analysis including the readmitting hospital characteristics, low procedure volume of a readmitting facility was significantly associated with non-index readmission (p < 0.001). Readmission to a lower-procedure-volume facility was associated with a 46%–75% increase in mortality (OR 1.46–1.75, p < 0.005) and a 21%–35% increase in major complications (OR 1.21–1.34, p < 0.005). Following adjustment for volume at a readmitting facility, admission to a non-index facility was no longer associated with mortality (OR 0.90, 95% CI 0.71–1.14, p = 0.378) or major complications (OR 1.09, CI 0.94–1.26, p = 0.248).
Of patient readmissions following brain tumor resection, 15.6% occur at a non-index facility. Low procedure volume is a confounder for non-index analysis and is associated with an increased likelihood of major complications and mortality, as compared to readmission to high-procedure-volume hospitals. Further studies should evaluate interventions targeting factors associated with unplanned readmission.