✓ The authors report a case of an aggressive chordoma in the cervical spine of a 15-year-old girl who underwent radical resection followed by reconstruction using an anterior vascularized fibular strut graft and posterior arthrodesis prior to receiving immediate postoperative radiation therapy. The patient had successful graft incorporation 4 months postoperatively. The authors review the advantages of using vascularized fibular strut grafts for the treatment of multilevel cervical spine neoplastic disease and discuss the theoretical advantages of using vascularized grafts that tolerate therapeutic levels of radiation.
Neill M. Wright, Bruce A. Kaufman, Bruce H. Haughey and Carl Lauryssen
Bruce A. Kaufman, Christopher J. Moran and James Schlesinger
Michael R. Chicoine, T. S. Park and Bruce A. Kaufman
✓ If the spasticity of cerebral palsy (CP) is reduced in children at a young age by selective dorsal rhizotomy, the incidence of lower-extremity deformities requiring orthopedic surgery may be reduced; however, this has never been investigated in detail. The authors examined the effects of selective dorsal rhizotomy on rates of lower-extremity orthopedic surgery in 178 children with CP. Age at selective dorsal rhizotomy ranged from 2 to 19.3 years (mean 5.5 years) with follow-up intervals ranging from 24 to 70 months (mean 44 months). Spastic CP was classified as quadriplegia (33%), diplegia (65%), and hemiplegia (2%). To assess the effects of early versus late rhizotomy on rates of orthopedic surgery, patients were grouped as follows: Group I underwent rhizotomy between 2 and 4 years of age (54 patients), and Group II underwent rhizotomy between 5 and 19 years of age (124 patients). Comparison of Kaplan—Meier plots of lifetime orthopedic surgery rates revealed that Group II underwent orthopedic surgery at a higher rate than Group I (p = 0.037). Analysis by procedure type revealed higher orthopedic surgery rates in Group II than Group I for heel cord releases (p = 0.0025), adductor releases (p = 0.018), and hamstring releases (p = 0.02). Orthopedic surgery rates were no higher for Group II compared to Group I for ankle/foot operations (p = 0.023), femoral osteotomy (p = 0.25), iliopsoas releases (p = 0.35), and “other” operations (p = 0.013). The data indicate that early rhizotomy reduces the need for orthopedic surgery for heel cord, hamstring, and adductor releases.
Shenandoah Robinson, Bruce A. Kaufman, John A. Jane Jr. and Tae Sung Park
Thomas Pennell, Juneyoung L. Yi, Bruce A. Kaufman and Satish Krishnamurthy
Mechanical failure—which is the primary cause of CSF shunt malfunction—is not readily diagnosed, and the specific reasons for mechanical failure are not easily discerned. Prior attempts to measure CSF flow noninvasively have lacked the ability to either quantitatively or qualitatively obtain data. To address these needs, this preliminary study evaluates an ultrasonic transit time flow sensor in pediatric and adult patients with external ventricular drains (EVDs). One goal was to confirm the stated accuracy of the sensor in a clinical setting. A second goal was to observe the sensor’s capability to record real-time continuous CSF flow. The final goal was to observe recordings during instances of flow blockage or lack of flow in order to determine the sensor’s ability to identify these changes.
A total of 5 pediatric and 11 adult patients who had received EVDs for the treatment of hydrocephalus were studied in a hospital setting. The primary EVD was connected to a secondary study EVD that contained a fluid-filled pressure transducer and an in-line transit time flow sensor. Comparisons were made between the weight of the drainage bag and the flow measured via the sensor in order to confirm its accuracy. Data from the pressure transducer and the flow sensor were recorded continuously at 100 Hz for a period of 24 hours by a data acquisition system, while the hourly CSF flow into the drip chamber was recorded manually. Changes in the patient’s neurological status and their time points were noted.
The flow sensor demonstrated a proven accuracy of ± 15% or ± 2 ml/hr. The flow sensor allowed real-time continuous flow waveform data recordings. Dynamic analysis of CSF flow waveforms allowed the calculation of the pressure-volume index. Lastly, the sensor was able to diagnose a blocked catheter and distinguish between the blockage and lack of flow.
The Transonic flow sensor accurately measures CSF output within ± 15% or ± 2 ml/hr, diagnoses the blockage or lack of flow, and records real-time continuous flow data in patients with EVDs. Calculations of a wide variety of diagnostic parameters can be made from the waveform recordings, including resistance and compliance of the ventricular catheters and the compliance of the brain. The sensor’s clinical applications may be of particular importance to the noninvasive diagnosis of shunt malfunctions with the development of an implantable device.
Sean M. Lew, Anne E. Matthews, Bruce A. Kaufman and Marike Zwienenberg
Bruce A. Kaufman, Lori Jones, Mary M. Zutter and T. S. Park
✓ The unusual presentation of acute megakaryoblastic leukemia as a temporal bone granulocytic sarcoma in an infant without systemic manifestations of leukemia is reviewed. Leukemia should be considered in the differential diagnosis of skull and skull-based lesions since the appearance on neuroradiological imaging is not unique in this diagnosis. Surgical treatment, as in this case, is limited to obtaining tissue for diagnosis and draining the infection.
Jeffrey G. Ojemann, T. S. Park, Robert Komanetsky, Richard A. A. Day and Bruce A. Kaufman
✓ The authors investigated the efficacy of anal sphincter electromyography (EMG) in identifying the lower sacral roots during selective dorsal rhizotomy. In nine children undergoing selective dorsal rhizotomy for cerebral palsy (CP) spasticity, direct electrical stimulation of the L1—S5 dorsal and ventral roots was performed while monitoring EMG responses from the anal sphincter and lower-extremity muscles. Anal sphincter activation was seen with stimulation of lumbosacral roots at many levels. Stimulation of dorsal and ventral roots gave anal sphincter EMG responses in 100% of the dorsal and ventral roots from L-4 and caudally. Only at the L-1 level did a minority of nerve roots have anal sphincter response to stimulation. Patterns of extremity muscle and sphincter activation specific to the S3–5 roots, namely anal sphincter activation without activation of other muscle groups, were found in only five (22%) of 23 roots stimulated. The pattern of stimulation responses in the majority of S3–5 roots indicated that the pathophysiology of lower-extremity spasticity in CP may involve the anal sphincter and does not spare the lower sacral roots. Thus, this study indicates that electrophysiological mapping alone, without anatomical identification, cannot be used to identify the lower sacral roots during selective dorsal rhizotomy for CP spasticity, and it proposes a model for investigation of associated bowel and bladder symptoms.
Paul Klimo Jr., Anne Matthews, Sean M. Lew, Marike Zwienenberg-Lee and Bruce A. Kaufman
Various surgical interventions have been described to evacuate chronic subdural collections (CSCs) of infancy. These include transfontanel percutaneous aspiration, subdural drains, placement of bur hole(s) with or without a subdural drain, and shunting. Shunt placement typically provides good long-term success (resolution of the subdural fluid), but comes with well-known early and late complications. Recently, the authors have used a mini–osteoplastic craniotomy technique with the goal of definitively treating these children with a single surgery while avoiding the many issues associated with a shunt. They describe their procedure and compare it with the traditional bur hole technique.
In this single-institution retrospective study, the authors evaluated 26 cases involving patients who underwent treatment for CSC. Preoperative, intraoperative, and postoperative data were reviewed, including radiographic findings (density of the subdural fluid and ventricular and subarachnoid space size), neurological examination findings, and intraoperative fluid description. The primary outcome was treatment failure, defined as the patient requiring any subsequent surgical intervention after the index procedure (minicraniotomy or bur hole placement).
Fifteen patients (10 male and 5 female; median age 5.1 months) collectively underwent 27 minicraniotomy procedures (each procedure representing a hemisphere that was treated). In the bur hole group, there were 11 patients (6 male and 5 female; median age 4.6 months) with 18 hemispheres treated. Both groups had subdural drains placed. The average follow-up for each treatment group was just over 7 months. Treatment failure occurred in 2 patients (13%) in the minicraniotomy group compared with 5 patients (45%) in the bur hole group (p = 0.09). Furthermore, the 2 patients who had treatment failure in the minicraniotomy group required 1 subsequent surgery each, whereas the 5 in the bur hole group needed a total of 9 subsequent surgeries. Eventually, 80% of the patients in the minicraniotomy group and 70% of those in the bur hole group had resolution of the subdural collections on the last imaging study.
The minicraniotomy technique may be a superior technique for the treatment of CSCs in infants compared with bur hole evacuation. The minicraniotomy provides greater visualization of the subdural space and allows more aggressive evacuation of the fluid, better irrigation of the space, the ability to fenestrate any accessible membranes safely, and continued egress of fluid into the subgaleal space. Although this preliminary report has obvious limitations, evaluation of this technique may be worthy of a prospective, multiinstitutional collaborative effort.
Bruce A. Kaufman, Anne E. Matthews, Marike Zwienenberg-Lee and Sean M. Lew
The authors report a retrospective review of their experience using nonpenetrating titanium anastomotic clips for dural closure in 27 pediatric cases (26 patients) of spinal surgery for a variety of diagnoses. The goal of this review was to define the utility of these clips in pediatric neurosurgical spinal procedures, identify complications of their use, and assess the effects on postoperative imaging because of their use.
Institutional review board approval was obtained for a retrospective chart review of all patients in whom titanium dural clips had been utilized. Patients were identified over a 2-year period using hospital and clinic records, and data were collected on the patient demographics, surgical diagnosis and procedure, durotomy location and length, and adjunctive closure methods. Postoperative complications were assessed. When available, postoperative imaging data were reviewed.
Twenty-six patients underwent 27 operations over a 20-month period. They ranged in age from 2.5 months to 18.5 years, with a median age of 3.2 years and an average age of 5.8 years. The operative diagnosis was some form of spinal dysraphism in 19 patients, with a syrinx or dural tear in 2 patients each, and an arachnoid cyst in 3 cases; 1 patient had a tumor resected. Operative levels included lumbosacral (19), thoracic (7), and cervical (1). Dural exposure was limited to 1 laminar level in 16 cases, 2 levels in 8, and 3 levels in 1; 2 cases involved focal dural tears. A combination of additional hemostatic and tissue sealant materials was applied over the clips in 16 cases. One patient required reoperation 13 months after clip placement. Prior clip use did not make subsequent exposure and opening more complicated. No significant complications were identified in the follow-up period ranging from 1 to 24 months. There were no documented CSF leaks. The clips are not easily seen on plain radiographs and did not cause artifacts or distortion on either CT or MR imaging.
Nonpenetrating titanium anastomotic clips afford an effective means of closure while limiting the exposure needed, and thus allowing more minimally invasive approaches. In tight spaces, dural closure is accomplished more easily and faster with the clips as compared with conventional suturing. No significant complications were seen from clip use, and the clips did not interfere with postoperative imaging.