The authors review current views on of the embryogenesis of the neural tube defects (NTDs) myelomeningocele and anencephaly. In this context, the following four approaches to the study of NTDs are discussed: normal morphogenesis and timing of early human neural development from conception to the ascent of the conus medullaris; mechanical and molecular biology of neural tube closure derived from experimental and animal models; morphological and biomechanical features of the NTDs myelomeningocele and anencephaly; and the experimental evidence for the importance of both genetic and environmental influences on human NTDs. Although considerable insight into both normal neural tube closure and the factor(s) by which this process may be disrupted has been reported in recent years, the exact mechanism(s) by which human myelomeningoceles and anencephaly arise remain elusive.
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Michael D. Partington, Daniel A. Rüfenacht, W. Richard Marsh, and David G. Piepgras
✓ The authors report a series of seven patients with myelopathy who were found to have spinal dural arteriovenous (AV) fistulas in which the nidus was located at some distance from the spinal cord. The nidus was intracranial in three cases and involved a sacral nerve root sheath in the other four, in each case, the arterialized draining vein led into the coronal plexus of medullary veins. A lack of normal draining radicular veins was noted in all cases. Magnetic resonance images were obtained in four patients and demonstrated spinal cord tissue changes only in the lower thoracic cord in three cases and in the cervical cord in one, all consistent with an ischemic process secondary to venous hypertension. Five patients were managed surgically by division of the draining vein, with improvement of the neurological deficit in all. One patient was treated by embolization alone and had stabilization of her deficit. The remaining patient in the series died of unrelated systemic disease before the spinal dural AV fistula could be treated.
These cases support the theory that venous hypertension is the dominant pathophysiological mechanism involved in spinal dural AV fistulas independent of their location. In patients with a suspected spinal dural AV fistula, lumbar and thoracic spinal angiography will reveal the site of the fistula in the majority of cases (88% in this series). In the remaining patients, the possibility of a remote fistula must be considered. The lack of normal venous drainage of the cord following injection in the artery of Adamkiewicz is the most reliable indicator of venous hypertension in the cord and can be helpful in making the decision to proceed with a search for a cranial or sacral arterial supply.
Michael D. Partington, Bernd W. Scheithauer, and David G. Piepgras
✓升高血清癌胚抗原(CEA)without evidence of neoplasia was noted in an 84-year-old woman. She subsequently developed a lytic skull lesion, which at surgery proved to be an atypical meningioma. Immunohistochemical analysis demonstrated that this tumor was producing CEA. This aggressive meningioma required two further resections and adjuvant radiotherapy in the following 18 months. Serum elevation of CEA has been reported only twice in association with meningiomas; both of those tumors were of the secretory subtype.
Emily Andrisevic, Marshall Taniguchi, Michael D. Partington, Julie Agel, and Ann E. Van Heest
Object
本文解决的争论是苏rgical treatment methods for a neuroma-in-continuity. The authors of this study chose to test the hypothesis that more severe nerve injuries, as distinguished by < 50% conduction across a neuroma-in-continuity, could be treated with neuroma resection and grafting, whereas less severe nerve injuries, with > 50% conduction across the neuroma, could be treated with neurolysis alone.
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The goal of this study was to compare preoperative and postoperative Active Movement Scale (AMS) scores in children with upper trunk brachial plexus birth injuries treated with neurolysis alone if the neuroma's conductivity was > 50% on intraoperative nerve testing. Seventeen patients (7 male, 10 female) met the criteria for inclusion in this study. Surgery was done when the patients were an average of 10 months old (range 6–19 months). The authors analyzed AMS scores from the preoperative assessment, 1-year postoperative follow-up visit, and subsequent follow-up assessment as close to 3 years after surgery as possible (referred to in this paper as > 2-year postoperative scores).
Results
Comparison of preoperative and 1-year follow-up data showed significant improvement in shoulder abduction, flexion, external rotation, and internal rotation; elbow flexion and supination; and wrist extension. Comparison of preoperative findings and results of assessment at > 2-year follow-up showed significant improvement in shoulder abduction, flexion, external rotation; and elbow flexion and supination. At final follow-up, useful function (AMS score of 6 or 7) was achieved for elbow flexion in 14 of 16 patients, shoulder flexion in 11 of 15 patients, shoulder abduction in 11 of 16 patients, and shoulder external rotation in 5 of 15 patients.
Conclusions
This report indicates that there is a subgroup of patients who can benefit clinically, with functional improvement of shoulder and elbow function, from treatment with neurolysis alone for upper trunk lesions demonstrating more than 50% conduction across the neuroma on intraoperative nerve testing. Patients with less than 50% conduction, indicating more severe disease, are treated with nerve resection and grafting in the authors' treatment algorithm.
Pituitary adenomas in childhood and adolescence
Results of transsphenoidal surgery
Michael D. Partington, Dudley H. Davis, Edward R. Laws Jr., and Bernd W. Scheithauer
✓ Pituitary adenomas are uncommon in childhood. Between 1975 and 1988, 36 patients underwent trans-sphenoidal resection at the Mayo Clinic before their 17th birthday. Fifteen (41.7%) had prolactin (PRL)-secreting tumors, 16 (44.4%) had adrenocorticotropic hormone (ACTH)-secreting tumors (including two patients with Nelson-Salassa syndrome), and three (8.3%) had tumors secreting growth hormone (GH); two patients (5.6%) had clinically nonfunctioning tumors. Of the 36 patients, 21 (58.3%) were girls, and girls predominated in every group except that with ACTH-secreting tumors, where they accounted for only 37.5% of the patients. The average age at the time of surgery was 14.7 ± 2.2 years, the youngest patient being 7.3 years old. The ACTH-secreting tumors were associated with an earlier onset of symptoms than the other tumor types: six (37.5%) of 16 patients became symptomatic before 10 years of age, compared with two (10.0%) of the 20 other patients. Presenting symptoms primarily reflected endocrine dysfunction, with neurological presentation (visual field deficits) occurring in only two patients.
这个病人组中没有人死亡。Significant operative morbidity included steroid-induced psychosis in one patient and diabetes insipidus in three, which resolved in two. Plurihormonal tumors, broadly defined as tumors producing more than one hormone, were common, comprising five (36%) of 14 PRL-secreting tumors, all three GH-secreting tumors, and one of two clinically nonfunctioning tumors, or 25.7% overall. Macroadenomas accounted for 89% of plurihormonal tumors. Long-term follow-up review (median > 5 years) revealed good control of PRL-secreting tumors (although five of 15 patients had received postoperative radiotherapy), contrasted with a 25% late recurrence rate for ACTH-secreting tumors, which had an 80% initial remission rate. The majority of patients had good endocrine function, including reproductive function. It is concluded that: 1) although pediatric pituitary adenomas occur primarily in adolescence, Cushing's disease is found at any age; 2) transsphenoidal surgery is feasible and safe in this age group; 3) plurihormonal tumors occur more frequently in the pediatric age group than in adults; and 4) long-term control rates in PRL- and ACTH-secreting tumors are probably similar to those seen in adults.
Jeffrey P. Blount and Michael D. Partington
Paige Lundy, Christian Kaufman, David Garcia, Michael D. Partington, and Paul A. Grabb
OBJECTIVE
The authors conducted a retrospective analysis of a consecutive series of children with intracranial subdural empyemas (SEs) and epidural abscesses (EAs) to highlight the important clinical difference between these two entities. They describe the delays and pitfalls in achieving accurate diagnoses and make treatment recommendations based on clinical and imaging findings.
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They reviewed their experience with children who had presented with intracranial SE and/or EA in the period from January 2013 to May 2018. They recorded presenting complaint, date of presentation, age, neurological examination findings, time from presentation to diagnosis, any errors in initial image interpretation, timing from diagnosis to surgical intervention, type of surgical intervention, neurological outcome, and microbiology data. They aimed to assess possible causes of any delay in diagnosis or surgical intervention.
RESULTS
Sixteen children with SE and/or EA had undergone evaluation by the authors’ neurosurgical service since 2013. Children with SE (n = 14) presented with unmistakable evidence of CNS involvement with only one exception. Children with EA alone (n = 2) had no evidence of CNS dysfunction. All children older than 1 year of age had sinusitis.
The time from initial presentation to a physician to diagnosis ranged from 0 to 21 days with a mean and median of 4.5 and 6 days, respectively. The time from diagnosis to neurosurgical intervention ranged from 0 to 14 days with a mean and median of 3 and 1 day, respectively. Delay in treatment was due to misinterpretation of images, a failure to perform timely imaging, progression on imaging as an indication for surgical intervention, or the managing clinician’s preference. Among the 14 cases with SE, initial imaging studies in 6 were not interpreted as showing SE. Four SE collections were dictated as epidural even on MRI. The only fatality was associated with no surgical intervention. Endoscopic sinus surgery was not associated with reducing the need for repeat craniotomy.
CONCLUSIONS
Regardless of the initial imaging interpretation, any child presenting with focal neurological deficit or seizures and sinusitis should be assumed to have an SE or meningitis, and a careful review of high-resolution imaging, ideally MRI with contrast, should be performed. If an extraaxial collection is identified, surgical drainage should be performed expeditiously. Neurosurgical involvement and evaluation are imperative to achieve timely diagnoses and to guide management in these critically ill children.
Willem Pondaag and Martijn J. A. Malessy
Mark S. Dias, Ming Wang, Menglu Liang, Elias B. Rizk, Robin Bowman, Michael D. Partington, Jeffrey P. Blount, Brandon G. Rocque, Betsy Hopson, Amy Lee, and William O. Walker
OBJECTIVE
The authors analyzed the National Spina Bifida Patient Registry (NSBPR), a national registry that tracks the outcomes for people with various forms of spinal dysraphism, to determine the ongoing longitudinal risk for tethered cord release (TCR) among adults with myelomeningocele who had not previously undergone TCR during childhood. The authors also sought to identify the impact of lesion level, ambulation status, and prior treatments for hydrocephalus or Chiari malformations on TCR rates.
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成年人在注册表中没有以前波形的rgone TCR during childhood were studied. This group was compared with the remaining adults in the registry. The frequency of first-time TCR and time to TCR (using Kaplan-Meier analysis) were determined independently for males and females. Cox proportional hazards analysis identified correlations between sex, best lesion level and ambulation status prior to TCR, and previous treatments for hydrocephalus and Chiari decompression.
RESULTS
Among 967 adults in the NSBPR (422 [43.6%] males and 545 [56.4%] females) who had not undergone TCR during childhood, the authors identified 47 people (4.9%) who underwent their first TCR during adulthood. This study cohort had significantly better mean functional motor levels and ambulation compared with the remaining adult cohort (both p < 0.001). The study group included 35 females (74.5%) and 12 males (25.5%); this sex distribution was significantly different in comparison with the remaining adult cohort (p = 0.016). The Kaplan-Meier curves for first TCR for females and males were significantly different (p = 0.01, log-rank test). TCR rates were correlated with sex (males had decreased risk; OR 0.31, 95% CI 0.16–0.62, p < 0.001), prior treatment for hydrocephalus (those who underwent prior treatment had decreased risk; OR 0.21, 95% CI 0.20–0.42, p < 0.001), and prior treatment for Chiari malformation (those who underwent prior treatment had greater risk; OR 3.84, 95% CI 1.50–9.88, p = 0.005).
CONCLUSIONS
成人脊髓脊膜突出那些逃脱的童年without undergoing TCR have an ongoing, albeit decreased, risk for spinal cord tethering requiring TCR. This risk is obviously not due to spinal column growth and therefore must reflect other factors such as dynamic changes in spinal cord health over time. Among people with MMC who underwent their first TCR as adults, females seemed to be overrepresented. Similar to the authors’ prior childhood study, people who underwent previous Chiari decompression seemed to be overrepresented, whereas those who underwent previous treatment for hydrocephalus seem to be underrepresented. These novel findings deserve further study.
Mark S. Dias, Ming Wang, Elias B. Rizk, Robin Bowman, Michael D. Partington, Jeffrey P. Blount, Brandon G. Rocque, Betsy Hopson, Daria Ettinger, Amy Lee, William O. Walker, and
OBJECTIVE
The aims of this study were to review the National Spina Bifida Patient Registry (NSBPR) data set to study the rates of tethered spinal cord release (TCR) among patients with myelomeningocele and variability between centers, to compare TCR rates between males and females, and to study the relationships between TCR rates and other condition-specific characteristics.
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The NSBPR registry was queried to identify all patients with myelomeningocele. TCR rates were calculated over time using survival analyses; rates between centers and between males and females were compared. Cox proportional hazards models were constructed to identify relationships between TCR rates and sex, functional lesion level, ambulation status, treated hydrocephalus, and prior Chiari decompression.
RESULTS
Of 6339 patients with information about their operations, 1366 (21.5%) underwent TCR, with significant variability between centers. The majority (75.8%) underwent a single TCR. The annual TCR rate was linear between birth and 13 years (1.8%/year) but declined sharply from 14 to 21 years (0.7%/year). There was no period of time at which the TCR rate accelerated. There were no significant differences in TCR rates between males and females. TCR rate was not related to functional lesion level but was lower among nonambulators compared with community ambulators (p = 0.005) and among those with treated hydrocephalus (HR 0.30, p < 0.001), and higher among those having prior Chiari decompression (HR 1.71, p < 0.001).
CONCLUSIONS
These results extend the results of prior single-institution studies, demonstrate significant treatment variability between institutions, and challenge the traditional concept that tethering is related to spinal cord stretching due to spinal growth.
