D. Douglas Cochrane

Long-Term Follow-Up Data from the Shunt Design Trial

Background: A previously reported multicenter randomized trial assessed whether 2 new shunt valve designs would reduce shunt failure rates compared to differential pressure valves. The study did not show a significant difference in the time to first shunt failure. Patients entered the trial between October 1, 1993, and October 31, 1995. The primary results were based on the patients’ status as of October 31, 1996 (a minimum follow-up of 1 year). This report describes the late complications based on the patients’ most recent follow-up. Methods: Three hundred and forty-four hydrocephalic children at 12 North American and European centers were randomized to 1 of 3 valves: a standard differential pressure valve; a Delta valve (PS Medical-Medtronic) or a Sigma valve (NMT Cordis). Patients were followed until their first shunt failure. Shunt failure was defined as shunt surgery for obstruction, overdrainage, loculation or infection. If the shunt did not fail, follow-up was continued until August 31, 1999. Results: One hundred and seventy-seven patients had shunt failure. Shunt obstruction occurred in 131, overdrainage in 13, loculated ventricles in 2 and infection in 29. The overall shunt survival was 62% at 1 year, 52% at 2 years, 46% at 3 years, 41% at 4 years. The survival curves for the 3 valves were similar to those from the original trial and did not show a survival advantage for any particular valve. Conclusions: Prolonged follow-up to date does not alter the primary conclusions of the trial: there does not appear to be one valve that is clearly the best for the initial treatment of pediatric hydrocephalus.

A randomized clinical trial to compare selective posterior rhizotomy plus physiotherapy with physiotherapy alone in children with spastic diplegic cerebral palsy.

A randomized controlled single‐blind trial was performed to compare lumbo‐sacral selective posterior rhizotomy (SPR) followed by intensive physiotherapy, with intensive physiotherapy alone in improving motor function in children with spastic diplegic cerebral palsy. Fifteen patients were randomly assigned to each treatment modality. Patients in the SPR group had rhizotomy within 1 month, followed by intensive outpatient physiotherapy for 9 months. Patients assigned to physiotherapy alone had identical intensive physiotherapy. There was a statistically significant and clinically important difference in improvement in motor function in favor of the SPR group, with a mean increase in total Gross Motor Function Measure (OMFM) score of 11.3% at 9 months for the SPR group compared with 5.2% for the physiotherapy‐only group (P=0.007). Significant improvements in spasticity (P<0.001) and range of movement (P<0.001) were noted in the SPR group compared to the physiotherapy‐only group. The results indicate that the improvement in motor function after SPR is more than can be explained by the associated intensive physiotherapy.

Cytogenetic analysis of 109 pediatric central nervous system tumors.

Reports of cytogenetic abnormalities in pediatric central nervous system (CNS) tumors are important for collection and comparison of large numbers of karyotypes of primary CNS neoplasms to produce statistically significant correlations. We report cytogenetic results of 119 samples of pediatric CNS tumors from 109 patients. Tumors included 33 low-grade astrocytomas, 18 high-grade astrocytomas, 14 gangliogliomas, 13 ependymomas, 17 primitive neuroectodermal tumors (PNET), three choroid plexus papillomas and carcinomas, and a miscellaneous group of 20 rare primary CNS tumors and metastases. In each group, cytogenetic results were correlated with histologic subtype and survival. The study indicated specific chromosome abnormalities in different groups of tumors. Low-grade astrocytomas showed mostly numeric abnormalities with gains of chromosome 7, high-grade astrocytomas showed differences from karyotypic changes observed in adults in lacking double minutes (dmin) and monosomy 10. The ependymoma group showed the largest proportion of abnormal karyotypes with frequent involvement of chromosome 6 and 16. Chromosome 6 was the single most common abnormal chromosome in this study, closely followed by chromosomes 1 and 11. Pediatric CNS neoplasms differ from adult tumors cytogenetically as well as histologically and biologically.

Long-term outcome and complications of children born with meningomyelocele

The long-term functional outcome of 101 children born with meningomyelocele between 1971 and 1981 was assessed, by a combination of retrospective chart review and follow-up assessments. The children had been managed at birth using a process ofnonstandardized selection. Eighty-three of the 101 patients survived after a minimum follow-up of 8.6 years, for a mortality rate of 18%. Forty-four of 83 children (53%) were community ambulators, and this correlated well with the presence of intact quadriceps function. Forty-eight children (58%) attended normal school and were grade-appropriate. Sixty-two of 83 patients (75%) were socially continent of urine, and 71/83 (86%) were socially continent of stool. Hydrocephalus was present in 93 of the 101 children in the study, and 85 children were shunted. Half of the shunted children required a shunt revision in the first year of life, and thereafter the rate of revision decreased, so that after 2 years the risk of revision was approximately 10% per year.

The influence of surgical operative experience on the duration of first ventriculoperitoneal shunt function and infection.

The relationship of surgeon experience, measured by operative volume, to the outcomes of ventricular shunt treatment of hydrocephalus in children is not clear. This paper explores this relationship based on first ventriculoperitoneal shunts (VPS) implanted in English-speaking Canada during the period from April 1989 to March 2001. Three thousand seven hundred and ninety-four first VPS insertions, performed by 254 surgeons, were reviewed. Surgical experience was represented by the number of shunt operations performed during the study period by each surgeon prior to the date of the operation. The 6-month shunt failure risk for less experienced surgeons was 38%, compared to 31% for more experienced surgeons. This difference decreased to 4% at 60 months and 3% at 120 months (p = 0.001). The infection rate for initial shunt insertions was 7% for patients treated by more experienced surgeons and 9.4% for those treated by less experienced surgeons (p = 0.006). A relationship between surgeon experience and shunt outcome that appears to be based on the operative experience that a surgeon brings to a procedure is in keeping with clinical experience. This observation has implications for public policy, service planning and surgical mentorship during the earlier years of a surgeon’s career.

The Surgical and Natural Morbidity of Aggressive Resection for Posterior Fossa Tumors in Childhood

The morbidity associated with gross total removal of pediatric posterior fossa tumors is well recognized although it is rarely isolated from other factors that comprise the management morbidity for these tumors. This study reviews (1) the operative and postoperative complications in 105 patients and (2) the neurological morbidity in a subset of 91 patients undergoing gross total removal of their tumor between 1982 and 1992. Gross total removal was achieved in 102 patients with a single procedure. Two patients with residual tumor underwent early repeat craniotomy for excision and 1 is being followed without repeat resection. Intra- and postoperative complications occurred in 33 patients and included hematoma requiring craniotomy (3), gastrointestinal hemorrhage (2), hydrocephalus requiring shunt placement (9), wound problems (4), and pseudomeningocele formation requiring additional treatment (5). Delayed onset hydrocephalus requiring shunting occurred in 2 patients and spinal deformity in 4 patients. Worsening of preoperative deficit (new cranial nerve palsies, worsening ataxia, bulbar dysfunction including apnea, mutism and seizures) occurred in 41% of patients operated on for primitive neuroectodermal tumors (PNET) (14/34), 53% of ependymomas (10/19), and 30% of astrocytomas (15/50). No patient who had a choroid plexus tumor was worsened by the procedure. Complete recovery of new postoperative deficits occurred in 14% of PNET (2/14), 50% of ependymoma (5/10) and 47% of astrocytoma (7/15), most often within 6 months of the procedure. Residual neurological morbidity, due to persistence of preoperative symptoms or due to deficits that occurred as the result of the surgical procedure, was assessed in a subgroup of 91 patients followed for an average of 48 months (2-147 months). This assessment did not include morbidity due to adjuvant therapy. Sixty-two percent of patients continued to exhibit abnormal cerebellar or bulbar signs. Forty-three percent of the total population exhibited limitation in function due to residual deficit. Only 38% of patients were both functionally normal and had a normal neurological examination at last follow-up.

Time to listen: a review of methods to solicit patient reports of adverse events

Background Patients have been shown to report accurate observations of medical errors and adverse events. Various methods of introducing patient reporting into patient safety systems have been published with little consensus among researchers on the most effective method. Terminology for use in patient safety reporting has yet to be standardised. Methods Two databases, PubMed and MEDLINE, were searched for literature on patient reporting of medical errors and adverse events. Comparisons were performed to identify the optimal method for eliciting patient initiated events. Results Seventeen journal publications were reviewed by patient population, type of healthcare setting, contact method, reporting method, duration, terminology and reported response rate. Conclusion Few patient reporting studies have been published, and those identified in this review covered a wide range of methods in diverse settings. Definitive comparisons and conclusions are not possible. Patient reporting has been shown to be reliable. Higher incident rates were observed when open-ended questions were used and when respondents were asked about personal experiences in hospital and primary care. Future patient reporting systems will need a balance of closed-ended questions for cause analysis and classification, and open-ended narratives to allow for patients limited understanding of terminology. Establishing the method of reporting that is most efficient in collecting reliable reports and standardising terminology for patient use should be the focus of future research.

Mutism after Posterior Fossa Tumour Resection in Children: Incomplete Recovery on Long-Term Follow-Up

Introduction: Mutism after posterior fossa tumour resection is generally said to be transient. Our experience suggested that speech did not usually normalise, and that mutism was associated with neurologic deficits that did not recover fully. Methods: Children with mutism after posterior fossa tumour resection, and alive more than 2 years post-operatively, were reviewed retrospectively. Charts were reviewed and parents contacted to ascertain details about mutism, associated neurologic deficits, and the most recent speech and neurologic status. Results: There were 7 children, with follow-up ranging from 2.5 to 13.1 years (mean 6.8 years). Tumours were midline, with 4 astrocytomas and 3 medulloblastomas. Mutism was noted immediately after post-operative extubation in all patients. Speech reappeared 1–15 weeks post-operatively, except for 1 patient, who remained mute at 2.5 years. Speech returned to normal in only 1 patient. Mutism was always accompanied by new or worsened cerebellar ataxia, which resolved incompletely in the long term. Sixth nerve palsies occurred in 3 and recovered incompletely. Seventh nerve paresis occurred in 2 and recovered completely. Conclusion: Mutism after posterior fossa tumour resection is associated with other neurologic deficits, particularly ataxia. Whereas speech usually returns, contrary to general opinion, speech rarely normalises. Other associated deficits rarely resolve completely. These findings have significant implications for counselling of family and patients.

Selective functional posterior rhizotomy for treatment of spastic cerebral palsy in children: review of 50 consecutive cases

Fifty consecutive children are described with spastic cerebral palsy treated with selective functional lumbar and sacral rhizotomy and followed for a minimum of 6 months. In all patients, spasticity improved postoperatively, but this was not necessarily accompanied by a functional improvement. Eighteen children who could not walk preoperatively were able to do so after rhizotomy. All 17 children who could walk preoperatively could do so following surgery, and in 15, gait was improved. Complications included transient urinary dysfunction in 4 children and sensory loss in 1. The operative procedure evolved with time: the technique of replacement laminotomy was refined; the electrophysiologic basis for selection of nerve rootlets changed after studies of nonspastic controls; smaller percentages of the L3 and L4 roots were sectioned in an attempt to prevent postoperative weakness of quadriceps, and there was a trend in the most recent patients to cut a smaller portion of all the posterior roots.

Prenatal spinal evaluation and functional outcome of patients born with myelomeningocele : Information for improved prenatal counselling and outcome prediction

OBJECTIVE Prenatal ultrasonography can localize the level of the spinal cord malformation, allowing prediction of the potential postnatal neurological deficit and functional prognosis. METHODS This study has two evaluations: (a) a retrospective prenatal review of 26 fetuses with spinal dysraphism (1987-1991), and (b) a follow-up descriptive study of patients (1971-1981) who underwent closure of the spinal lesion and ventricular shunting in the neonatal period. RESULTS Prenatal ultrasound evaluation enabled the accurate definition of the last intact vertebral level which allows separation of fetuses into three functional groups (last intact level L2, L3-4, L5-sacral). Patterns of ambulation, urinary and bowel continence, and school performance vary according to level of spinal lesion and the neurological deficit. The need for ventricular shunts, the incidence of other spinal malformations and surgical interventions did not vary with the level of the spinal lesion. CONCLUSIONS The functional outcome for patients with myelomeningocele is variable; however, distinct patterns emerge based on the level of spinal dysraphism and the resultant neurological deficit. By relating the level of the fetal spinal lesion to outcome data, more precise functional prognoses can be given to families.