Growth hormone insensitivity syndrome associated with syringomyelia and type I Chiari malformation.
(33/233)
A 49-year-old man with syringomyelia and a Type I Arnold-Chiari malformation (Chiari-I) was diagnosed with growth hormone insensitivity syndrome (GHIS). He was short in stature, had high circulating levels of GH, and low circulating levels of insulin-like growth factor-I (IGF-I) and IGF binding protein-3 (IGFBP-3). His GH responses to the administration of growth hormone-releasing hormone (GHRH) and L-DOPA were normal, but his levels of IGF-I and IGFBP-3 did not increase after the administration of exogenous GH. Direct genomic DNA sequencing revealed neither a mutation nor deletion in this patient's GH receptor (GHR) gene, though one polymorphism was detected, indicating that his GHR gene was normal. This is the first reported case of an association of GHIS with syringomyelia and Chiari-I malformation. (+info)
Effect of craniocervical decompression on peak CSF velocities in symptomatic patients with Chiari I malformation.
(34/233)
BACKGROUND AND PURPOSE: Peak CSF velocities detected in individual voxels in the subarachnoid space in patients with Chiari I malformations exceed those in similar locations in the subarachnoid space in healthy subjects. The purpose of this study was to test the hypothesis that the peak voxel velocities are decreased by craniocervical decompression. METHODS: A consecutive series of patients with symptomatic Chiari I malformations was studied before and after craniocervical decompression with cardiac-gated, phase contrast MR imaging. Velocities were calculated for each voxel within the foramen magnum at 14 time points throughout the cardiac cycle. The greatest velocities measured in a voxel during the cephalad and caudad phases of CSF flow through the foramen magnum were tabulated for each patient before and after surgery. The differences in these velocities between the preoperative and postoperative studies were tested for statistical significance by using a single-tailed Student's t test of paired samples. RESULTS: Eight patients with a Chiari I malformation, including four with a syrinx, were studied. Peak caudad velocity diminished after craniocervical decompression in six of the eight patients, and the average diminished significantly from 3.4 cm/s preoperatively to 2.4 cm/s postoperatively (P =.01). Peak cephalad velocity diminished in six of the eight cases. The average diminished from 6.9 cm/s preoperatively to 3.9 cm/s postoperatively, a change that nearly reached the significance level of.05 (P =.055). CONCLUSION: Craniocervical decompression in patients with Chiari I malformations decreases peak CSF velocities in the foramen magnum. The study supports the hypothesis that successful treatment of the Chiari I malformation is associated with improvement in CSF flow patterns. (+info)
Syringobulbia: a surgical appraisal.
(35/233)
Syringobulbia is a term which has been clinically applied to brain stem symptoms or signs in patients with syringomyelia. Syringobulbia clefts are found on investigation or at necropsy caused by cutting outwards of the CSF under pressure from the fourth ventricle into the medulla. These should be differentiated from the ascending syringobulbia which may occur from upward impulsive fluid movements in a previously established syringomyelia. Clinical analysis of 54 patients suggests that bulbar features are most often found with neither of the above mechanisms but are due to the effects of pressure differences acting downward upon the hind-brain with consequent distortion of the cerebellum and brainstem, traction on cranial nerves or indentation of the brain-stem by vascular loops. The commonest symptoms in the 54 patients were headache (35), vertigo (27), dysphonia or dysarthria (21), trigeminal paraesthesiae (27), dysphagia (24), diplopia (16), tinnitus (11), palatal palsy (11) and hypoglossal involvement (11). Careful attention to hydrocephalus is advisable before craniovertebral surgery, but the decompression of the hindbrain and the correction of craniospinal pressure dissociation remains the mainstay of surgical treatment. The results of careful surgery are good, 45 of the 54 cases reported improvement. Most of the reported deterioration occurred in a few patients who did conspicuously badly. (+info)
Theoretical analysis of the pathophysiology of syringomyelia associated with adhesive arachnoiditis.
(36/233)
OBJECTIVE: To apply a theoretical model to analyse the derangement of cerebrospinal fluid (CSF) dynamics in syringomyelia associated with adhesive arachnoiditis. METHODS: An electrical circuit model of CSF dynamics in the spine was used. With this model, the derangement of CSF dynamics in adhesive arachnoiditis was simulated. The effects of various surgical procedures were then analysed, such as syringo-subarachnoid shunting, subarachnoid bypass, and foramen magnum decompression. RESULTS: When CSF flow in the subarachnoid space was obstructed at a certain point, the pressure inside the spinal cord increased in the segment immediately distal to the blockage. This location of increased pressure corresponded to the preferred site of syrinx formation in adhesive arachnoiditis. Syringo-subarachnoid shunting, subarachnoid bypass, and foramen magnum decompression were all effective at reducing this pressure gradient. CONCLUSIONS: Blockage of the spinal subarachnoid CSF pathway produces a relative increase in the pressure inside the spinal cord distal to the blockage point. Repetitive formation of this pressure gradient then induces CSF leakage into the spinal parenchyma, leading to the formation of syringomyelia. Using this model, alternative surgical procedures could be suggested that might be effective in treating this disease. (+info)
Effects of opening peritumoral syrinxes on motor evoked potentials during resection of an intramedullary spinal cord tumor--case report.
(37/233)
A 29-year-old woman presented with mild tetraparesis caused by an intramedullary cervical cord tumor extending from the C-5 to C-6 levels associated with rostral and caudal syrinxes extending to the C-1 and C-7 levels. Transcranial motor evoked potential (MEP) monitoring was carried out during tumor resection using high-frequency repetitive electrical stimulation. When the rostral syrinx was opened, the MEP amplitude in the right upper limb suddenly decreased by about 50%. When the caudal syrinx was opened, the amplitude immediately recovered to the baseline. During dissection of the attachment of the tumor, the amplitude decreased again by 70%, and did not recover. The tumor was totally removed. The histological diagnosis was ependymoma. Postoperatively, motor weakness in the right arm deteriorated but gradually recovered. The initial loss of amplitude on opening of the rostral syrinx may have resulted from distortion of the intramedullary pressure that compromised function of the motor tract nearby. Opening of the caudal syrinx normalized the intramedullary pressure and allowed the MEP to recover. Intraoperative monitoring of MEPs is valuable in minimizing injury to corticospinal pathways, but care must be taken in evaluating changes in MEP. Intramedullary spinal tumors with associated syrinxes are not rare, so surgeons should realize that opening of a syrinx can lead to MEP changes. (+info)
Effects of surgery on the sensory deficits of syringomyelia and predictors of outcome: a long term prospective study.
(38/233)
OBJECTIVE: To quantify the effects of surgery on the thermal deficits of syringomyelia and assess the predictors for such effects. METHODS: The subjects were 16 consecutive patients (12 men, 4 women; mean (SD) duration of sensory symptoms, 5.1 (4.5) years) presenting with the typical symptoms of syringomyelia related to Chiari I malformation or trauma, and requiring surgical treatment. They were evaluated before surgery, then at six months and two years. Sensory evaluation included determination of the extent of thermal deficits and quantitative assessment of thermal, mechanical, vibration detection, and pain thresholds. Neuropathic pain intensity was evaluated on visual analogue scales. Magnetic resonance imaging was done before and after surgery to measure syrinx dimensions. RESULTS: The magnitude and extent of thermal deficits improved in a subgroup of patients and this was best predicted by the duration of sensory symptoms: patients operated on less than two years after the onset of their symptoms tended to improve, while those operated on later were stabilised or deteriorated slightly. The effect of surgery on thermal deficits was correlated with the duration of sensory symptoms. Surgery also affected vibration deficits in patients with the Chiari malformation, neuropathic pain on effort, and syrinx dimensions. CONCLUSIONS: The duration of sensory deficits is the best predictive factor of the efficacy of surgery for the thermal symptoms of syringomyelia. Early surgery is required if these deficits are to be minimised. (+info)
Results of the treatment of syringomyelia associated with Chiari malformation: analysis of 60 cases.
(39/233)
We analyze the results of surgical treatment of 60 patients presenting syringomyelia (SM) associated with Chiari malformation (CM) who were operated in the period 1982-2000. For each case, analysis covered 15 signs and 16 symptoms included in a protocol that separated SM signs and symptoms from those of CM. A score system was established in parallel with the protocol to make the evaluation of treatment results easier. All cases were submitted to craniovertebral decompression by C1 and eventually C2 laminectomy and cerebellar tonsillectomy with duramater graft. To evaluate the results, statistical proportion difference tests and variance analyses were made to a reliability index of 95% (p=0.05). We conclude that the statistical improvement of CM signs and symptoms was very significant (p=0). Syringomyelia signs and symptoms also improved significantly, except for "upper limb hyporeflexia", which did not improve. No statistical difference in the improvement of SM symptoms as compared to CM symptom was found. Syringomyelia signs improved statistically more than CM signs. In half of patients, the percent improvement of signs and symptoms ranged between 40% and 60%. (+info)
Vertebral malformation, syringomyelia, and ventricular septal defect in a dromedary camel (Camelius dromedarius).
(40/233)
An occipitoatlantoaxial malformation and ventricular septal defect (VSD) were diagnosed in a 36-hour-old female camel. Physical examination revealed a firm protrusion of the dorsal aspect of the atlas and axis, tilting of the head to the left, and a grade V/VI systolic murmur. Neurological examination revealed proprioceptive deficits and ataxia of all 4 limbs. Radiographic examination and necropsy demonstrated malformation, fusion of the atlas to the occiput and hypoplasia of the dens of the axis, and subluxation of the atlantoaxial joint. Dorsoventral laxity of the atlantoaxial joint was also present, with compression of the cervical spinal cord. A 1.5-cm-diameter VSD was observed also. Histopathologic examination of the cervical spinal cord revealed a cavity extending from the level of the first to fourth cervical segment, dorsal to the central canal, 5 cm long and 1-2 mm in diameter. The cells around the cavity were positive for glial fibrillary acidic protein and sporadically positive for vimentin. This cavitary structure was consistent with syringomyelia, which was lined by glial cells, surrounded by edematous white matter with Wallerian-like degeneration and with neuronal necrosis in the adjacent dorsal horns. (+info)