✓Tethering of the conus medullaris is assumed to be the primary cause of the deterioration seen in children with transitional lipomyelomeningocele (LMMC). The inevitability of deterioration has led to the use of prophylactic interventions to stabilize or prevent further clinical deterioration. The author reviewed current literature to define the timing and pattern of deterioration prior to and following initial cord untethering in patients with transitional LMMC, as well as the operative burden that these children bear in exchange for optimized function.
D. Douglas Cochrane
D. Douglas Cochrane
D. Douglas Cochrane
John R. W. Kestle, D. Douglas Cochrane, and James M. Drake
The potential for increased complications related to the arrival of new residents in July each year has not previously been demonstrated in the neurosurgical literature. The authors investigated this phenomenon in children undergoing cerebrospinal fluid shunt surgery.
Data were obtained from a multicenter hydrocephalus clinical trials database and from hospital admission records in English-speaking Canada. Data pertaining to patients treated in July and August were compared with those pertaining to patients treated during the remainder of the year. The incidence of shunt failure, shunt infection, neurological deficits, wound infection, technical errors, and death were compared using a chi-square test for categorical outcomes, means for continuous outcomes, and survival analysis for time-dependent outcomes.
In the hydrocephalus clinical trials database, 138 of 737 patients were treated in July and August. The median duration of shunt lifespan (hereafter referred to as “shunt survival”) was 1.7 years for patients treated during the summer months and 2.4 years for those treated throughout the rest of the year (p = 0.10); for shunt infection the figures were 13.8 and 8.8% (p = 0.08) of the total number of cases, and for wound dehiscence they were 2.9 and 0.7% (p = 0.05), respectively. When all shunt procedures were included, an examination of shunt survival and infection incidence rates recorded in the Canadian Hospital Discharge Database seemed to imply a significant advantage to having surgery between September and June (log-rank statistic = 7.10, p = 0.008).
The data suggest a “July effect” on some outcomes related to shunt surgery, but the effect was small. Nonetheless, the potential morbidity of shunt failure, infection, and the cost of treatment indicate that continued vigilance and appropriate supervision of new staff by attending surgeons is warranted.
Monique Marguerie and D. Douglas Cochrane
Albert Tu, Alexander R. Hengel, and D. Douglas Cochrane
Although patients with lumbosacral lipomas may be asymptomatic at presentation, most develop neurological symptoms over time. Given the challenges in examining infants, the authors sought to determine whether MRI would be helpful in identifying patients who are more likely to deteriorate early in life and who would potentially benefit from early surgical intervention.
A retrospective review of all patients with lumbosacral lipomas who were seen at the authors' institution between 1997 and 2013 and who were managed without prophylactic surgery was performed. The clinical history and imaging results for each patient were reviewed in detail and then correlated to the pattern of and age at clinical deterioration.
Twenty-four patients were identified. Nine worsened within the first 18 months of life (early deterioration), and 15 patients deteriorated or remained stable after 30 months (late deterioration/stable). No patients worsened between 18 and 30 months of age. Patients who deteriorated early were more likely to have large intradural lipomas that filled the canal, increased during the 1st year of life, and compressed neurological structures. Some had a syrinx extending above the neural-lipoma interface. Syrinxes in patients with early deterioration were large and expanded in infancy. Patients with early deterioration had motor deficits at the time of deterioration, whereas patients with late deterioration developed mixed urological and motor dysfunction.
Patients with large lipomas displacing the cord and an enlarging syrinx have a propensity for early clinical deterioration. Given this, their families may be counseled that 1) the risk of deterioration in infancy may be higher than in infants without these features, and 2) they require more diligent observation. Intervention before deterioration in these infants should also be considered. Patients without these features may be safely observed to a lesser extent.
Christopher M. Bonfield, D. Douglas Cochrane, Ash Singhal, and Paul Steinbok
Sagittal craniosynostosis, the most common single suture craniosynostosis, is treated by numerous surgical techniques. Minimally invasive endoscopy-assisted procedures with postoperative helmeting are being used with reports of good cosmetic outcomes with decreased morbidity, shortened hospital stay, and less blood loss and transfusion. This procedure uses small skin incisions, which must be properly placed to provide safe access to the posterior sagittal and lambdoid sutures. However, the lambda is often hard to palpate through the skin due to the abnormal head shape. The authors describe their experience with the use of intraoperative, preincision ultrasound localization of the lambda in patients with scaphocephaly undergoing a minimally invasive procedure. This simple technique can also be applied to other operations where proper identification of the cranial sutures is necessary.
John C. L. Sun, Paul Steinbok, and D. Douglas Cochrane
✓ The spontaneous resolution of syringomyelia has been reported infrequently. In patients with Chiari I malformations, resolution of the syringomyelia has sometimes been associated with improvement of their malformation. The authors present a case of spontaneous resolution followed by recurrence of syringomyelia and a corresponding change in the Chiari malformation. This case is of interest in light of the theories postulated to explain spontaneous resolution of syringomyelia.
Calvin K. W. Tong, James C. H. Chen, and D. Douglas Cochrane
Morquio syndrome, or mucopolysaccharidosis type IV, is a rare enzyme deficiency disorder and results in skeletal dysplasia. Odontoid dysplasia is common among affected patients, resulting in atlantoaxial instability and spinal cord compression. Surgical treatments include decompression and prophylactic fusion, during which intraoperative neuromonitoring is important to alert the surgical team to changes in cord function so that they can prevent or mitigate spinal cord injury. This report describes a 16-year-old girl with Morquio syndrome who developed paraplegia due to thoracic spinal cord infarction during foramen magnum and atlantal decompression. This tragic event demonstrates the following: 1) that patients with Morquio syndrome are at risk for ischemic spinal cord injury at levels remote from areas of maximal anatomical compression while under anesthesia in the prone position, possibly due to impaired cardiac output; 2) the significance of absent motor evoked potential responses in the lower limbs with preserved upper-limb responses in an ambulatory patient; 3) the importance of establishing intraoperative neuromonitoring baseline assessments prior to turning patients to the prone position following induction of anesthesia; and 4) the importance of monitoring cardiac output during prone positioning in patients with chest wall deformity.
Paul Steinbok and D. Douglas Cochrane
✓ Between 4% and 8% of cases of spina bifida cystica occur in a cervical or cervicothoracic location. Despite a large body of literature concerning spinal dysraphism, there has been little written specifically about patients afflicted with this disorder in a cervical location. Eight children who presented at birth with posterior cervical or cervicothoracic lumps, all of which represented a dysraphic state, are discussed. Two types of abnormalities were noted. Three patients had hydromyelia with an associated myelocystocele herniating posteriorly into a meningocele sac. In these three patients there was an associated Chiari II malformation and hydrocephalus. The other five children had a meningocele in which a band of tissue extended from the posterior aspect of the spinal cord through a defect in the bone and fascia to the posterior part of the meningocele sac itself. No patient had a lesion that could be described as a meningomyelocele. The investigation and surgical management of these conditions are discussed and the need for intradural exploration to untether the spinal cord in the cervical region is stressed.