Search PubMed⌕ Search

Biomedical subjects

B A Kaufman

Publications and source records attributed to B A Kaufman.

At least 37 records · Page 2Linked to original sources

Selective dorsal rhizotomy and rates of orthopedic surgery in children with spastic cerebral palsy.

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.

Adolescent↗

Familial colloid cyst of the third ventricle: case report and review of associated conditions.

The cases of a father and his son who were diagnosed with pathologically confirmed colloid cysts of the third ventricle are presented. The familial occurrence of this tumor is rare and suggests that genetic factors may play a role in its formation. Consistent with the concept that the cyst originates as a developmental abnormality, it is associated with a variety of congenital defects. The conditions that are associated with these tumors are discussed.

Adult↗

Posterior fossa decompression without duraplasty in infants and young children for treatment of Chiari malformation and achondroplasia.

Some children with Chiari malformation and achondroplasia require posterior fossa decompression that typically includes expansion of the dural tube with duraplasty. Infants and young children, however, may have a more distensible dura mater than do older patients. Furthermore, the structures that compress the hindbrain of young patients may be the bone and abnormally thickened atlantooccipital membrane, i.e., dural band, rather than the dura mater. We have treated 7 children who had Chiari malformation or achondroplasia with posterior fossa decompression without duraplasty. All children were symptomatic; 3 had Chiari-I malformations, 2 Chiari-II malformations, and 2 achondroplasia. The age range was 3 months to 2.5 years (mean 15.1 months). The exent of tonsillar herniation and other hindbrain anomalies was assessed on preoperative magnetic resonance imaging. The infants with Chiari-II malformations underwent cervical laminectomies, whereas the other young children with Chiari-I malformations or achondroplasia underwent suboccipital craniectomy as well as cervical laminectomy. In Chiari malformation, the dural band was divided; in achondroplasia, there was no identifiable dural band. Following bony decompression and division of the identifiable dural band, immediate expansion of the stenotic region with visible cerebrospinal fluid space posterior to the neural elements could be ascertained by intraoperative ultrasonography. During a follow-up period ranging from 4.5 months to 4 years (mean 22 months), all patients made improvements in their symptoms, 3 having complete resolution of their symptoms. This preliminary experience indicates that in children 2 years of age or younger, posterior fossa bony decompression without duraplasty can be effective treatment for Chiari malformations or achondroplasia.

Achondroplasia↗

Subdental synchondrosis fracture in children: the value of 3-dimensional computerized tomography.

A case is presented illustrating the usefulness of computerized tomography (CT) with 3-dimensional (3-D) reconstruction for evaluation of a subdental synchondrosis fracture in a child. Odontoid fractures in children less than 7 years of age occur at the subdental synchondrosis and are typically diagnosed with plain x-rays. However, a delay in diagnosis is common as these injuries may not be appreciated on initial roentgenographic evaluation. The authors present a case of a 2-year-old boy with a subdental synchondrosis fracture secondary to trauma. In this patient, plain x-ray and conventional axial CT failed to definitively elucidate the child's injuries; however, the use of CT with 3-D reconstruction fully delineated the injury. The use of CT with 3-D reconstruction in evaluating children with subdental synchondrosis fractures is a valuable tool for diagnosis. The treatment of synchondrosis fractures of the odontoid process in children is immobilization of the cervical spine.

Child↗

Predictors of ability to walk after selective dorsal rhizotomy in children with cerebral palsy.

Serial evaluations were completed after selective dorsal rhizotomy on 90 children with spastic cerebral palsy to analyze whether age, the preoperative gait score, voluntary dorsiflexion at the ankle, the diagnosis (quadriplegia or diplegia), or the length of follow-up correlated with the ability to walk after rhizotomy. The preoperative gait score (P < 0.0001), the diagnosis (diplegia versus quadriplegia, P < 0.0001), unilateral dorsiflexion (P = 0.0029), and bilateral dorsiflexion (P < 0.0001) were significant predictors of the maximal postoperative gait score in the univariate regression analysis, but only the preoperative gait score (P < 0.0001) and the diagnosis (P = 0.0015) retained significant predictive power in the multivariate analysis. These data suggest that the preoperative gait score and the diagnosis are the strongest predictors of ability to walk after selective dorsal rhizotomy. Dorsiflexion demonstrated predictive power only in the univariate model, suggesting that it might have some prognostic value but less than the preoperative gait score or the diagnosis.

Cerebral Palsy↗

A region of consistent deletion in neuroblastoma maps within human chromosome 1p36.2-36.3.

Deletion of the short arm of human chromosome 1 is the most common cytogenetic abnormality observed in neuroblastoma. To characterize the region of consistent deletion, we performed loss of heterozygosity (LOH) studies on 122 neuroblastoma tumor samples with 30 distal chromosome 1p polymorphisms. LOH was detected in 32 of the 122 tumors (26%). A single region of LOH, marked distally by D1Z2 and proximally by D1S228, was detected in all tumors demonstrating loss. Also, cells from a patient with a constitutional deletion of 1p36, and from a neuroblastoma cell line with a small 1p36 deletion, were analyzed by fluorescence in situ hybridization. Cells from both sources had interstitial deletions of 1p36.2-36.3 which overlapped the consensus region of LOH defined by the tumors. Interstitial deletion in the constitutional case was confirmed by allelic loss studies using the panel of polymorphic markers. Four proposed candidate genes--DAN, ID3 (heir-1), CDC2L1 (p58), and TNFR2--were shown to lie outside of the consensus region of allelic loss, as defined by the above deletions. These results more precisely define the location of a neuroblastoma suppressor gene within 1p36.2-36.3, eliminating 33 centimorgans of proximal 1p36 from consideration. Furthermore, a consensus region of loss, which excludes the four leading candidate genes, was found in all tumors with 1p36 LOH.

Base Sequence↗

MR angiography in pediatric neurological disorders.

MR angiography using 3D and 2D time-of-flight techniques were used to evaluate pediatric neurological disorders. MRA (arteriography) and MRV (venography) were abnormal in 63 and 45 cases, respectively. Conventional cerebral angiography was performed in 30 cases. These techniques were compared with MRI and conventional angiography. In addition, the value of MR angiography for surgical planning was subjectively evaluated. Our results showed that intracranial vessels were invariably better shown on MR angiography than on MRI. MRA and MRV were most useful in evaluating vascular distortions related to congenital brain malformations and intracranial tumors. MRA was valuable in detecting arterial narrowing but overestimated the degree of stenosis compared with conventional angiography. MRV was the technique of choice for evaluation of dural sinus and cerebral venous thrombosis and compression. MRA played little to no role in preoperative planning of vascular malformations and aneurysms. It did not appear to be accurate in assessing tumor vascularity or lesions in small arteries and arteritis.

Adolescent↗

Computer tomographic scanning within 24 hours of craniotomy for a tumor in children.

Computed tomographic (CT) brain scans were performed without and with contrast enhancement within 24 h of craniotomy in 26 patients undergoing 27 operations. Postoperative scans were retrospectively reviewed for evidence of contrast enhancement, the pattern of enhancement and the presence of blood on the postoperative scans. Contrast enhancement was seen in the resection bed in 33% of patients undergoing gross total resection of their lesions, and was absent in 50% of patients with known residual disease. Enhancement along a corticotomy was present in 18% and distant meningeal enhancement was identified in 19% of patients. These enhancement rates were unrelated to steroid dosages, duration of surgery, or the interval between operation and scanning. It was not possible to delineate residual tumor in 63% of the patients, due to a postoperative enhancement pattern that stimulated enhancing vessels, the presence of hemorrhage, or due to the absence of calcification or preoperative enhancement. None of the scans were affected by technical problems (motion artifact, inability to complete the scan) potentially associated with scanning within 24 h of craniotomy. Small amounts of residual tumor remain undetectable, particularly due to hemorrhage in the resection bed. Although no distinct advantage in defining residual disease was obtained compared to scanning at 72 h, the overall rate of findings not related to neoplasm was slightly less for scans obtained within 24 h.

Astrocytoma↗

Chondroid chordoma of the lateral skull base.

Clinical, radiological, and pathologic features of an intracranial chondroid chordoma in a 9-year-old boy are described. This is the first reported case of a chordoma, the center of which was laterally situated in the cranial base, lying in or near jugular foramen and carotid canal, but without midline involvement. Although cranial chordomas in childhood are extremely rare, and all previously reported cases appeared to have arisen in the clivus, this location should not be considered ectopic. Forking at the rostral end of the notochord has been demonstrated in embryos, and would be the presumed embryological source for this tumor. This is also the first reported case of a chondroid chordoma in a child with immunohistochemical documentation distinguishing it from a chondrosarcoma. This chondroid chordoma contained two populations of cells: neoplastic cartilage and chordoid tissue in a myxoid stroma. The distinction between chordoma and chondrosarcoma and the implications on treatment will be discussed.

Child↗

Spinal magnetic resonance imaging immediately after craniotomy for detection of metastatic disease.

Although magnetic resonance imaging (MRI) may be more sensitive than myelography with CT scanning in detecting spinal metastatic disease (SMD), the limitations of these MRI examinations have not been defined. The feasibility of obtaining early postoperative MRI to screen for SMD, and the type and frequency of imaging abnormalities were evaluated in this prospective study. Twenty-seven patients (78% with nondisseminating neoplasms or nonneoplastic diseases) were studied with postoperative spinal MRI without and with contrast enhancement, obtained within 24 h of craniotomy. Procedural problems with immediate spinal MRI were identified. Physician monitoring of the examination did not guarantee an adequate examination, and small abnormalities were missed or incompletely evaluated at the time of the MRI. Surprisingly, abnormal signal from intraspinal gas, blood, or blood breakdown products was not seen. In the absence of metastatic disease, spinal meningeal enhancement was absent. True SMD was detected, but nonneoplastic focal contrast enhancement (false positive) occurred in 11%. An unusual nonneoplastic subdural cerebrospinal fluid enhancement was seen in 3 of 13 (23%) of all patients undergoing posterior fossa craniectomies. This enhancement could hide small metastases or could be confused for SMD. Although immediate postoperative spinal MRI is potentially effective as a screening tool for the detection of SMD, we have identified some significant limitations of this technique.

Adolescent↗

Changes in hip migration after selective dorsal rhizotomy for spastic quadriplegia in cerebral palsy.

Selective dorsal rhizotomy is increasingly used for management of spastic quadriplegic cerebral palsy but rates of hip stability following the operation have not been reported. Determining hip stability by radiographic measurement of lateral migration of the femoral head beyond a lateral edge of the acetabulum after dorsal rhizotomy allows an objective assessment of the outcome of the operation. This prospective study examined the effect of selective dorsal rhizotomy on lateral migration of the femoral head in 45 children with spastic quadriplegic cerebral palsy. The children ranged in age from 2 to 9 years (average 5 years 1 month) and were grouped according to their ages with 23 children in the 2- to 4-year-old group and 22 children in the 5- to 9-year-old group. Postoperative follow up ranged from 7 to 50 months (average 20 months). The Reimers migration percentage (MP), a measure of the lateral migration of the femoral head, was calculated from anteroposterior hip radiographs taken prior to the operation and at the last follow-up examination. Of the 90 hips involved, 9% improved, 80% remained unchanged, and 11% worsened, yielding a radiographic stability rate of 89%. The hips with postrhizotomy worsening of the MP had an average preoperative MP of 14% (range 9% to 38%) and an average postoperative increase in MP of 18% (range 11% to 37%). Of the 45 children, four subsequently underwent unilateral derotational femoral osteotomies for persistent or worsening hip subluxation. There was a significant tendency for the MP to worsen in patients with lower prerhizotomy MP values (chi 2 = 20.74, df = 4, p = 0.001), but the age of patients and their ambulatory status at the time of rhizotomy had no bearing on postoperative hip stability. The data indicate that selective dorsal rhizotomy prevents progressive lateral migration of the femoral head in the majority of children who undergo the operation for spastic quadriplegia.

Cerebral Palsy↗

Fast spin-echo magnetic resonance imaging for radiological assessment of neonatal brachial plexus injury.

Neurosurgical management of birth-related brachial plexus palsy involves observing the patient for a period of several months. Operative intervention is usually undertaken at 3 to 6 months of age or more in infants who have shown little or no improvement in affected muscle groups. Ancillary tests such as electromyography and nerve conduction studies are occasionally useful. No radiological study has been consistently helpful in operative planning, except for contrast computerized tomography (CT) myelography, which requires general anesthesia in infants. This is because the infant's small size exceeds the functional resolution of the imaging modalities. This report describes the use of a special sequence of magnetic resonance (MR) imaging entitled "fast spin echo" (FSE-MR). Unlike CT myelography, this technique provides high-speed noninvasive imaging that allows clinicians to evaluate preganglionic nerve root injuries without the use of general anesthesia and lumbar puncture. The utility of this technique is illustrated in three cases, two involving either infraclavicular exploration or a combination of infraclavicular and supraclavicular exposure based on FSE-MR findings. The FSE-MR imaging offers an excellent alternative to contrast CT myelography in evaluation of infants with birth-related brachial plexus injuries.

Birth Injuries↗

Frontal plagiocephaly secondary to synostosis of the frontosphenoidal suture. Case report.

Frontal plagiocephaly may arise from either synostotic or deformational forces. Deformational causes of frontal plagiocephaly can be distinguished from synostotic causes by differences seen on physical examination, which can then be confirmed by skull x-ray films and if necessary three-dimensional computerized tomography (CT). Unilateral coronal synostosis is the main synostotic cause of frontal plagiocephaly, although it has also been seen with fusion of the frontozygomatic suture. In several syndromes presenting with bilateral coronal synostosis, fusion of the frontosphenoidal and frontoethmoidal sutures is also present. The authors report, for perhaps the first time, a case showing synostotic frontal plagiocephaly secondary to fusion of the frontosphenoidal suture alone. Although the phenotypic appearance is superficially similar to that seen in unilateral coronal synostosis, analysis of the cranial base shows markedly different effects: angulation of the anterior cranial base with respect to the posterior cranial base away from the synostotic side and angulation of the posterior cranial base with respect to the midpalatal suture also away from the synostotic side. In unilateral coronal synostosis, both angulations are toward the synostotic side. These effects on the cranial base alter its relationship to the cranial vault and the facial skeleton. Most important, frontal plagiocephaly secondary to fusion of the frontosphenoidal suture should not be overlooked as being deformational. Because this fusion is difficult or impossible to visualize by skull x-ray films, three dimensional CT must be obtained in cases that are not clearly identified as deformational plagiocephaly by physical examination.

Cranial Sutures↗

Dedifferentiated chondrosarcoma in childhood: report of a case.

Dedifferentiated chondrosarcoma is an unconventional chondrosarcoma of distinctive pathology. The tumor, not previously reported in childhood, is characterized by a very poor prognosis with an average survival of only 6 months. Imaging features include a lytic lesion, focal calcifications, and a soft tissue mass.

Child↗

Linkage mapping of the tumor necrosis factor receptor 2 (TNFR2) gene to 1p36.2 using the single-strand conformation polymorphism technique.

We identified two informative polymorphisms in the transcribed 3' untranslated region of the tumor necrosis factor receptor 2 (TNFR2) gene using the polymerase chain reaction (PCR) with the single-strand conformation polymorphism (SSCP) technique. These polymorphisms demonstrated Mendelian inheritance and were useful for linkage analysis. TNFR2 was very closely linked to the pronatriodilatin gene (PND), and the TNFR2 SSCP polymorphisms were much more informative than the restriction fragment length polymorphisms currently available for the PND locus. In addition, we have demonstrated that genotyping could be performed with DNA obtained from paraffin-embedded tissue.

Base Sequence↗

Complete migration of peritoneal shunt tubing to the scalp.

The entire length of distal tubing from a ventriculoperitoneal shunt was found to have migrated into the subgaleal space, and resulted in a shunt obstruction. Upward migration of distal shunt catheters has rarely been reported, but probably involves patient motion that creates a "windlass" effect. Cephaled migration requires a potential space (subgaleal or ventricular) and no resistance to movement of the tubing. This complication can be prevented by securing the shunt near the site of motion.

Child, Preschool↗