摘要:

&NA;Magnetic resonance imaging (MRI) was performed in a series of 21 children and adolescents who had been hospitalized after sustaining closed head injuries of varying severity at least 6 months previously. Areas of high intensity in the parenchyma were present in 8 of the 11 severely injured patients, whereas MRI findings were normal in all 10 patients with mild‐to‐moderate head injuries. Lesions involving the subcortical white matter were confined to severely injured patients whose clinical features were compatible with diffuse axonal injury. Neuropsychological assessment disclosed deficits primarily in the severely injured patients; these deficits were significantly associated with persistent lesions visualized by MRI. Serial MRI and neurobehavioral assessment following early injury may be useful in documenting cognitive impairment in relation to structural alterations of the young brain. (Neurosurgery24:223‐227, 1989)

ISSN:0148-396X    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;Anesthetized lambs were subjected to epidural cord compression at T13 by means of an epidural balloon distended to 200 mmHg for 80 minutes. Determinations of spinal cord blood flow (SCBF) were made by labelled microspheres prior to and during compression, and then ½, 1½, and 2½ hours after compression. Twelve control animals received saline (80 ml/h). Nine animals received hetastarch (a 20 ml/kg bolus followed by an 80 ml/h infusion) and 8 animals received mannitol (a 1 g/kg bolus followed by 1 g/kg/hr). An additional 10 animals received phenylephrine to raise mean arterial pressure by 20 to 40%. Somatosensory evoked potentials (SEPs) were recorded following each determination of SCBF. Animals were killed following determination of the 2½ hour postcompressive flow. The animals treated with either hetastarch or phenylephrine had a postcompressive mean arterial pressure that was significantly greater than that of the controls (P< 0.01). During treatment, cardiac output in the hetastarch and mannitol animals was significantly greater and hematocrit significantly less than in the controls (P< 0.05). In spite of these changes, postcompressive SCBF was significantly increased only in those animals treated with phenylephrine (P< 0.05). Statistical analysis of the relationship between mean arterial pressure and postcompressive SCBF revealed that autoregulation is indeed lost with this experimental model of spinal cord injury. Histological examination of the injured site failed to demonstrate any difference in the area of hemorrhagic necrosis among the four groups. Electrical conduction across the injured site, as measured with SEPs, was lost 10 minutes following balloon inflation and did not recover during the 2½ hour duration of this experiment. (Neurosurgery24:228‐234, 1989)

ISSN:0148-396X    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;Three years ago we reported our preliminary results regarding treatment of intractable spasticity with use of intrathecal morphine. This paper is a follow‐up report of 12 patients who underwent implantation of a pump or reservoir for delivery of intrathecal morphine sulfate for control of spasticity. Our primary concern initially was that patients would ultimately become drug tolerant and lose the beneficial effect of the morphine. Only one of these 12 patients has developed drug tolerance. The longest follow‐up period has been 4.3 years, and this patient has maintained excellent control of his spasticity with a stable dose of 2 mg of morphine daily. (Neurosurgery24:236‐238, 1989)

ISSN:0148-396X    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;From 1976 to 1986, 681 patients with drug‐refractory trigeminal neuralgia (TN)—typical in 641, symptomatic of multiple sclerosis in 23 and of tumor in 10, atypical in 5, and postherpetic in 2—were treated with various percutaneous procedures. Controlled differential thermocoagulation of the gasserian ganglion and/or retrogasserian rootlets was performed in 533 patients; glycerolization of the trigeminal cistern in 32; and compression of the gasserian ganglion by balloon catheter in 159, Results and complications of each procedure are assessed at a mean follow‐up of 6.5 years for thermocoagulation, 5 years for glycerolization, and 3.5 years for compression. The following therapeutic protocol is proposed: 1) in TN patients at first operation:a) gasserian compression (or glycerolization, if experience warrants it) is indicated in all cases of typical TN, unless the 3rd division alone is affected;b) in the latter case and in symptomatic TN, we suggest thermocoagulation; 2) in recurrences:a) after glycerolization or gasserian compression, gasserian compression (or glycerolization) is indicated;b) after thermocoagulation or open surgery, thermocoagulation is suggested. (Neurosurgery24:239‐245, 1989)

ISSN:0148-396X    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;The utility of evoked potentials in monitoring spinal cord and cerebral function in various neurosurgical and orthopedic operations has now been established. To study the effects of graded hypotension upon spinal and cortical somatosensory evoked potentials (SEPs), and spinal motor evoked potentials (SMEPs), 12 anesthetized cats were subjected to graded hypotension ranging from a mean arterial blood pressure of 100 mmHg to 30 mmHg or less. Hypotension causes a progressive increase in onset latency and a decrease in amplitude and conduction velocity of SEPs and SMEPs. Cortical SEPs and SMEPs were sensitive to profound hypotension (MAP < 30 mmHg). Spinal SEPs showed more resistance and disappeared at lower levels of hypotension. Immediate blood transfusion caused resumption of cortical SEPs and SMEPs within 30 minutes after infusion; however, the latency and amplitude of responses did not reach the baseline values within 1 hour after transfusion. The sequential recovery of evoked responses was dependent upon the length of hypotension. When 15 minutes elapsed between loss of responses and transfusion, cortical SEPs and SMEPs did not resume within 1 hour after infusion. No return of signals occurred if 30 minutes elapsed between the loss of evoked responses and blood reperfusion. These findings suggest that ischemia associated with profound systemic hypotension can alter or obliterate evoked responses. (Neurosurgery24:246‐252, 1989)

ISSN:0148-396X    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;The influence of anesthetics usually used for neuroleptic anesthesia—nitrous oxide, fetanyl, flunitrazepam, and thiopental sodium—on motor evoked potentials (MEP) was examined in 15 patients during neurosurgical operations on the spinal cord, in 16 patients in traumatic coma, and in 6 healthy volunteers. MEP were recorded from the contralateral thenar and anterior tibial muscles in response to single transcranial electrical stimuli on the motor cortex. Intraoperatively, during neuroleptic anesthesia we found the amplitudes to be reduced to an average of 11% of the preoperative baselines for the thenar potentials, and to 7% of the preoperative baselines for the anterior tibial muscle potentials, despite a maximum stimulus strength of 750 V. A similar reduction of MEP amplitudes was observed in 6 volunteers during breathing of an oxygen/nitrous oxide mixture (34%/66%), whereas fentanyl, flunitrazepam, and thiopental had only a minor effect on MEP. We conclude that with respect to anesthesia‐related suppression of amplitudes, an average of 5 to 15 electromyographic responses should be evaluated for intraoperative monitoring of MEP using the technique described here. (Neurosurgery24:253‐256, 1989)

ISSN:0148-396X    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;During a 14‐month period, 129 individuals underwent 140 operations for microvascular decompression to relieve hemifacial spasm, disabling positional vertigo, tinnitus, or trigeminal neuralgia at our institution. Seven patients were operated upon twice on the same side and 4 were operated upon on both sides at different times. In each case, the brainstem auditory evoked potentials were monitored intraoperatively by the same neurophysiologist. In 75 of these operations, compound action potentials were also recorded from the exposed 8th nerve. Comparison of speech discrimination scores before the operation and at the time fo discharge showed that at discharge, discrimination had decreased in 7 patients by 15% or more and increased in 4 patients by 15% or more, in 2 patients by as much as 52%. Essentially similar results were obtained when preoperative speech discrimination scores were compared with results obtained from the 87 patients who returned for a follow‐up visit between 3 and 6 months after discharge. Only one patient lost hearing (during a second operation to relieve hemifacial spasm). Another patient (also operated upon to relieve hemifacial spasm) suffered noticeable hearing loss postoperatively, but had recovered nearly normal hearing by 4 months after the operation. Nine patients had an average elevation of the hearing threshold for pure tones in the speech frequency range (500 to 2000 Hz) of 11 dB or more at 4 to 5 days after the operation; 8 of these had fluid in their middle ears that most likely contributed to the hearing loss. Threshold elevations occurred at 4000 Hz and 8000 Hz in 19 and 29 ears, respectively. (Neurosurgery24:257‐263, 1989)

ISSN:0148-396X    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;Bony fusion is frequently required for anatomical reconstruction and stabilization of the spine. This review discusses bone structure, healing after fracture, and bony fusion, including the use of autografts and allografts. Research should be done on preparation of the bed, the nature and quantity of bone to be used, and how best to immobilize the spine. (Neurosurgery24:264‐270, 1989)

ISSN:0148-396X    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;We report the case of a 61‐year‐old man in whom numbness developed on the right side of the penis, scrotum, and perineum after he jumped into a swimming pool. Magnetic resonance imaging and a computed tomographic scan disclosed a lesion at S1‐S2 impinging on the right S2 nerve root. At surgery, ruptured disc material originating in an area normally occupied by the fixed fibrocartilaginous plate was identified and excised. Postoperatively, the numbness resolved. We discuss a possible cause of the rupturing of the sacral disc and recommended treatment by laminectomy and excision, as in other cases of ruptured disc at other levels of the spinal column.(Neurosurgery24:271 ‐272, 1989)

ISSN:0148-396X    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;Preoperative radiological evaluation with magnetic resonance imaging and computed tomography was valuable in planning the surgical management of a destructive lesion of the posterior elements of the thoracic spine that was causing spinal cord compression in an 18‐year‐old woman. Preoperative recognition of bilateral involvement of the pedicles in addition to the laminae and spinous process led to use of prophylactic segmental stabilization of the spine with Luque rods after successful excision of an aneurysmal bone cyst. This case provides an example of the usefulness of computed tomographic scanning and magnetic resonance imaging in assessing the distribution and location of vertebral tumor and its potential effect on spinal stability. The efficacy of combining radical excision with stabilization for treatment of aneurysmal bone cysts of the spine is emphasized. (Neurosurgery24:273‐276, 1989)

ISSN:0148-396X    

出版商:OVID    

年代:1989

数据来源: OVID