Synovial cysts of the spine

A series of 13 patients with synovial or ganglion cysts of the spinal facet joints causing nerve root compression is reported. These cysts were found in both the cervical and the lumbar spine, and the anatomical location of each cyst corresponded to the patient's signs and symptoms. In no case was there evidence of intervertebral disc abnormality found at operation. The patients ranged from 49 to 77 years of age and included 4 men and 9 women. Radiographic evidence of facet degenerative change and degenerative spondylolisthesis was frequently but not invariably noted. The extradural defects defined with positive contrast myelography or postmyelography computed tomographic scanning were usually posterior or posterolateral to the common dural sac and were misinterpreted as extruded discs in the majority of cases. Treatment consisted of laminectomy and surgical excision of cysts. All patients reported improvement or resolution of their presenting symptoms.     

Postoperative lumbar extradural arachnoid cyst. Report of two cases and review of the literature

Two cases of postoperative extradural arachnoid cyst in the lumbar region were reported. The symptoms such as lumbago, sciatica and paresis of foot which were perfectly cured at discharge relapsed after several months of daily business. The two patients were readmitted and reexamined by myelography and computer assisted tomography. In the two patients a cystic pooling of metrizamide having a connection with the subarachnoid space was noted in the same way. At the second operation a small dural tear and an extradural arachnoid cyst were recognized similarly. Burres and coworkers reported that an extradural arachnoid cyst would easily grow through a small dural defect in the lumbar region, because the hydrostatic pressure is higher than that of the cervical level. Our two cases might well coincident with their theory. In consequence of the experience of the two postoperative extradural arachnoid cyst, we give emphasis that even though the dural tear would be small, especially in the lumbar region, it should not be overlooked and be closed carefully with fine sutures.     

Dural repair for intraspinal extradural meningeal cyst

A 52-year-old woman presented with an intraspinal extradural meningeal cyst in the thoracolumbar region manifesting as progressive sensory disturbance of the bilateral lower extremities. Magnetic resonance imaging and computed tomography myelography showed an extradural meningeal cyst extending from the T-12 to L-4 levels in the thoracolumbar region with a dural defect and a valve-like mechanism developed in the enlarging cyst. Operative findings revealed a dural defect that allowed communication between the extradural cyst cavity and the subarachnoid space. Surgical resection of the cyst wall and repair of the dural defect resolved the symptoms.     

Role of computed tomography and myelography in the diagnosis of central spinal stenosis

In order to evaluate radiographic methods for diagnosing central lumbar stenosis, we reviewed the computed tomography scans and myelograms of twenty-four patients who underwent surgical decompression for central lumbar stenosis. In the diagnosis of central lumbar stenosis, the measurement of the anterior-posterior diameter of the osseous canal by computed tomography was less reliable than the measurement of the dural sac by myelography. The dimensions of the canal derived from computed tomography provided a correct diagnosis in 20 per cent of the patients, while myelography was accurate 83 per cent of the time. The effectiveness of computed tomography was improved when the cross-sectional area of the dural sac was measured. We suggest that a narrow dural sac, demonstrated by myelography or by computed tomography, reliably indicates central spinal stenosis.     

Problems of posterior lumbar interbody fusion (PLIF) for the rheumatoid spondylitis of the lumbar spine

We performed posterior lumbar interbody fusion (PLIF) on 7 patients with rheumatoid spondylitis (RA) of the lumbar spine with severe low-back pain and/or cauda equina symptoms, and evaluated the effectiveness of PLIF for the lumbar spinal instability in RA secondary to destruction of the anterior elements, including vertebral endplates and the apophyseal joint. The subjects were 7 patients with classic RA, 2 men and 5 women, mean age 65 years old, and the mean duration of RA was 21 years. All had severe low-back pain and difficulty with walking. According to the ARA classification, the patients were at stage 3 or worse and in class 3. Diagnostic imaging including magnetic resonance imaging (MRI), tomography, myelography, and computed tomographic myelography (CTM) of the lumbar spine clearly delineated pathology, destruction of the vertebral endplate, subluxation, and cauda compression which can be well treated with PLIF. We performed L4/5PLIF (5 cases), L3/4 and L4/5 PLIF (2 cases), and posterior fixation with instruments for anterior column repair and stabilization and posterior decompression. Autografts (all cases) and Brantigan IF cage (2 cases) were used. Stable fixation of the lumbar spine was achieved after surgery, and improvement in gait and activities of daily living were achieved through the relief of low-back pain and radicular pain; the mean duration of follow-up was 22 months. Postoperative, plain radiography, CT, and MRI revealed the enlargement of the lumbar canal and fusion and incorporation of grafted bone, but in some cases, collapse of graft, migration of pedicle screw, instability of adjacent level, and collapse of adjacent vertebra were noted. PLIF with spinal instruments is a preferred treatment for rheumatoid spondylitis of the lumbar spine, but in the mutilating type of RA with severe osteoporosis, PLIF in combination with a long fixation system and/or augmentation of the vertebral bodies might be needed.     

Computed tomographic epidurography: an aid to understanding deformation of the lumbar dural sac by epidural injections.

Local anaesthetics injected into the epidural space may deform the dural sac to a variable degree, thereby contributing to variability in the extent of the block. We investigated deformation of the lumbar dural sac after injection into the lumbar epidural space. The subjects were 26 patients with low-back pain who underwent lumbar epidurography and computed tomographic (CT) epidurography, of whom seven also underwent myelography and computed tomographic myelography. The epidural space was entered via the sacral hiatus in 24 patients and through the L5/S1 interspace in two patients. Ten millilitres of local anaesthetic was then injected into the epidural space followed by 20 mL of contrast medium. Computed tomographic epidurography was undertaken approximately 30-min after the epidural injection at the mid-vertebral and mid-discal levels from the first lumbar through to the first sacral vertebrae. The dural sac usually showed an oval or hexagonal shape on the transverse views at the first and second lumbar vertebral levels, and the shape of an inverted triangle below the level of the third lumbar vertebra. A median line of translucency was also observed on the posteroanterior epidurographic view in 25 of the 26 patients. This line was though to be a manifestation of the dural deformation to the inverted triangle. Dural sac deformation usually shows a specific pattern, although there are individual variations. Dural deformability is an important consideration in any analysis of the spread of epidural block or of the changes of epidural pressure after epidural injection of local anaesthetics.     

Extradural spinal arachnoid cysts associated with spina bifida occulta

Summary Introduction. Spinal extradural arachnoid cysts are an uncommon cause of neural compression in children. Even more uncommon is the association of such cysts with spina bifida occulta. Material. Two girls, 12 and 8-years-old, presented with left leg pain, deteriorating gait, clinical signs of left L5 and S1 root compression, without bladder or bowel symptoms. The first patient had left foot drop. The second patient had muscle wasting and smaller left foot with pes cavus. Radiographs showed spina bifida occulta of S1 in both. MRI revealed an extradural cyst at the S1 level, indenting the thecal sac and the L5 and S1 roots. At operation in both patients a large arachnoid cyst arising from a small dural defect in the axilla of the left S1 root was compressing and displacing it and the dural sac. It was removed and the defect was repaired. The first patient improved with complete recovery of the foot drop. An MRI at 12 months showed no cyst recurrence. The second patient made good recovery initially, but at 10 months developed recurrent symptoms. An MRI scan showed recurrence of the cyst with root compression. On repeat exploration a different dural defect was identified in a more anterior position and was repaired. Discussion. The coexistence of extradural arachnoid cyst and corresponding bifid spinal segment has not been described previously. It raises the suspicion that the dural defect giving rise to the arachnoid cyst may be due to segmental dural dysgenesis in the context of the dysrhaphic neuroectodermal malformation.     

Recurrent subdural hematoma caused by cerebrospinal fluid leakage. Case report

The authors report a case of a recurrent subdural hematoma (SDH) that was caused by a persistent cerebrospinal fluid (CSF) leak from an L1-2 fistula. A 34-year-old man experienced severe headaches due to SDH, and he underwent aspiration of subdural fluid four times due to recurrent collections. Further evaluation with computerized tomography (CT) myelography demonstrated extradural extravasation of contrast through an L1-2 fistula. The patient underwent an L1-2 laminectomy; a small dural defect with CSF leakage at the left nerve root sleeve was found and was repaired. Following the repair, the patient had no further recurrence of SDH. Recurrent SDH, caused by spontaneous CSF leakage through a lumbar CSF fistula, is extremely rare. In cases of recurrent SDH, radiographic workup with spinal CT myelography should be considered.     

Diastematomyelia and intramedullary epidermoid spinal cord tumor combined with extradural teratoma in an adult. Case report

Diastematomyelia is rarely diagnosed in the adult. Only a few such cases have been reported in the literature. A 26-year-old Mexican man with lumbar diastematomyelia is reported who also harbored a T-12 intramedullary epidermoid tumor and an extradural teratoma located in the dorsal aspect of the dural sac opposite L-4. These three rare coincidental lesions were removed at surgery. The patient's condition improved.     

Radiologic findings of the lumbar spine in patients with rheumatoid arthritis,and a review of pathologic mechanisms

We have analyzed the radiologic findings on the lumbar spine and the clinical symptoms in patients with rheumatoid arthritis (RA). A total of 106 patients who fulfilled the revised criteria of the American Rheumatism Association were subjected. All of the patients were asked to fill out a questionnaire about the existence of low back pain, leg pain, and leg numbness. Radiologic features of the lumbar spine, including scoliosis, spondylolisthesis, disc space narrowing, endplate erosion, osteophyte, and osteoporosis, were checked. Radiographs of the cervical spine were also taken. The clinical background of RA, such as mutilating disease or not, was assessed. Forty-two patients (40%) had the symptoms of low back pain. Abnormal radiologic findings in lumbar spine were detected in 57%. The prevalence of clinical symptoms tended to be higher in the patients with endplate erosion. Forty-two percent of the patients had both lumbar and cervical lesions. The prevalence of lumbar lesion was not high in the mutilating type of RA, except for facet erosion and severe osteoporosis. The patients with pulse steroid therapy revealed a higher prevalence of vertebral fracture. From these results, we concluded that lumbar lesions were frequently observed in patients with RA. The possibility of lumbar lesions as well as the lesions in the cervical spine and peripheral joints should be examined in patients with RA.     

Transabdominal ultrasound measurement of the lumbar spinal canal. Its value for evaluation of lumbar spinal stenosis

Lumbar spinal stenosis, most commonly caused by hypertrophic changes in the soft tissues of the spinal canal, is itself a clinical entity, but in the early phase it can also serve as a factor influencing general back disorder morbidity. It can be identified reliably by measuring the anteroposterior diameter of the dural sac on myelography films and/or the transverse area of the dural sac on computed tomography (CT) scans. In the present study, 76 patients with general back disorders were examined with ultrasound (US) transabdominally through the intervertebral disc. In those 50 patients (66%) in which all three of the lowest lumbar intervertebral spaces could be visualized, the measurements made by US differed by +/- 5 mm from those obtained by myelography and +/- 25 mm2 from those made by CT. In a subset of ten patients with spinal stenosis, US was able to demonstrate the small size of the dural sac, but the cause of the stenosis could not be reliably evaluated. In addition to diagnosing central spinal stenosis, ultrasonography is also well suited for screening purposes.     

脊髓造影联合感觉诱发电位检测在下腰段脊神经根性卡压伤治疗中的临床指导意义

目的探讨脊髓造影(myelography,MG)联合感觉诱发电位(somatosensory evoked potential,SEP)检测在治疗下腰段脊神经根性卡压性病变治疗中的临床价值。方法2004年3月~2006年10月对46例患有不同程度腰腿疼痛1年以上且有手术意向的患者常规行MG和双下肢胫神经及L5、S1皮节SEP检测,分别记录硬膜囊受压部分占椎管直径的比例、N40峰潜伏期及H反射延迟状况,综合分析两种检查结果,最终决定是否行手术处理并预测愈后。结果7例单节段硬膜囊受压未超过椎管直径30%的患者,有2例患者SEP检测N40延迟比对照组超出10%,另5例延迟在0.15s之内<10%。前者手术治疗,后者采用非手术治疗处理。34例患者硬膜囊单节段(26例)和双节段(8例)受压程度大于椎管直径的30%,其中MG检查单节段单侧根管不显影21例,双侧不显影5例;多节段8例存在单侧根管不显影2例和双侧不显影6例,而此34例患者SEP检测H反射延迟均>10%,皆选用手术治疗。还有5例患者虽然MG下硬膜囊受压小于椎管直径的30%,其SEP延迟又>10%,但是其振幅却正常,其中2例患者单侧根管显示不清,此2例患者行手术治疗。结论MG和SEP检查可以作为下腰段脊神经受损害的量化指标,二者互为补充,指导临床治疗方式并提示愈后,对尚无CT或MRI设备的基层医疗单位有较高的应用价值。     

Dynamic changes in the dural sac of patients with lumbar canal stenosis evaluated by multidetector-row computed tomography after myelography

Purpose

Some reported studies have evaluated the dural sac in patients with lumbar spinal stenosis (LSS) by computed tomography (CT) after conventional myelography or magnetic resonance imaging (MRI). But they have been only able to evaluate static factors. No reports have described detailed dynamic changes in the dural sac during flexion and extension observed by multidetector-row computed tomography (MDCT). The aim of this study was to elucidate or demonstrate, in detail, the influence of dynamic factors on the severity of stenosis.

Methods

One hundred patients with LSS were enrolled in this study. All underwent MDCT in both flexion and extension positions after myelography, in addition to undergoing MRI. The anteroposterior diameter (AP-distance) and cross-sectional area of the dural sac (D-area) were measured at each disc level between L1–2 and L5–S1. The dynamic change in the D-area was defined as the absolute value of the difference between flexion and extension. The rate of dynamic change (dynamic change in D-area/D-area at flexion) in the dural sac at each disc level was also calculated.

Results

The average AP-distance in flexion/extension (mm) was 9.2/7.4 at L3–4 and 8.3/7.4 at L4–5. The average D-area in flexion/extension (mm²) was 96.3/73.6 at L3–4 and 72.3/61.0 at L4–5. The values were significantly lower in extension than in flexion at all disc levels from L1–2 to L5–S1. AP-distance was narrowest and D-area smallest at L4–5 during extension. The rates of dynamic changes at L2–3 and L3–4 were higher than those at L4–5.

Conclusions

MDCT clearly elucidated the dynamic changes in the lumbar dural sac. Before surgery, MDCT after myelography should be used to evaluate the dynamic change during flexion and extension, especially at L2–3, L3–4, and L4–5.     

Intraspinal epidermoid tumors in children: problems in recognition and imaging techniques for diagnosis

Iatrogenic intraspinal epidermoid tumors are very rare. The similarity of the clinical manifestations of the tumor with other childhood problems can pose a problem in diagnosis. In addition, because of the lag in time between the lumbar puncture and the development of a symptomatic tumor, this relationship is overlooked and can cause a delay in diagnosis, as in the present report of four children. Magnetic resonance imaging was found to be superior to myelography in defining the tumor and its relationship to other structures inside the dural sac. All patients underwent surgical excision, with subsequent resolution of symptoms.     

Spontaneous thoracic spinal cord herniation--case report.

A 54-year-old female presented with spontaneous thoracic spinal cord herniation manifesting as chronic progressive motor weakness in both legs. Spastic paraparesis (4/5) and pathological reflexes such as ankle clonus were noted. She also had mild bladder dysfunction but no bowel dysfunction. She had no sensory disturbance, including tactile and pinprick sense. Magnetic resonance (MR) imaging revealed that the atrophic spinal cord was displaced into the ventral extradural space at the T4-5 intervertebral level with markedly dilated dorsal subarachnoid space. Computed tomography obtained after myelography showed no evidence of intradural spinal arachnoid cyst. She underwent surgical repair of the spinal cord herniation via laminectomy, and spinal cord herniation through the ventral dural defect was confirmed. Postoperative MR imaging revealed improvement of the spinal cord herniation, but her symptoms were not improved. Spontaneous spinal cord herniation is a rare cause of chronic myelopathy, occurring in the upper and mid-thoracic levels, and the spinal cord is usually herniated into the ventral extradural space. Early differential diagnosis from intradural spinal arachnoid cysts is important for a satisfactory outcome.     

Expansive duraplasty for the treatment of spinal extradural arachnoid cysts: case report

The authors report the case of a 25-year-old man with a thoracolumbar extradural arachnoid cyst who underwent expansive duraplasty. Symptoms, preoperative magnetic resonance imaging features, and intraoperative findings suggested the involvement of entrapment neuropathy in the manifestation of symptoms. To the authors' knowledge, this case represents the first evidence that expansive duraplasty can achieve complete resolution of the symptoms in a patient with a spinal extradural arachnoid cyst. The results indicate that duraplasty may be an alternative option in cases in which complete resection of the lesion is difficult and widening of the dural sac is necessary at surgery.     

Hemorrhagic lumbar facet cysts accompanying a spinal subdural hematoma at the same level

Abstract

Context

We present a rare and interesting case of hemorrhagic lumbar facet cysts accompanying a spinal subdural hematoma at the same level suggesting a possible mechanism by which spinal subdural hematomas can arise.

Findings

A 71-year-old man presented with persistent sciatic pain and intermittent claudication. Magnetic resonance imaging demonstrated a multilocular mass lesion that showed high signal intensity in both T1- and T2-weighted images, and was located both inside and outside of the spinal canal. Computed tomographic myelography showed a cap-shaped block of the dural tube at L5 and computed tomography with L5–S facet arthrography demonstrated cystic masses. The patient was diagnosed with lumbar radiculopathy caused by hemorrhagic facet cysts, and then progressed to surgical treatment. Surgery revealed that the cysts contained blood clots, and intraoperative findings that the inside of the dural tube appeared blackish and that the dural tube was tensely ballooned after removal of the cysts led us to explorative durotomy. The durotomy demonstrated concentrated old blood pooling both in the dorsal and ventral subdural space, and these spaces were subsequently drained. After surgery, his sciatic pain and intermittent claudication resolved. There was no evidence of cyst mass recurrence at 2 years of follow-up.

Conclusion

We propose a newly described mechanism for the formation of spinal subdural hematomas. We recommend surgeons be alert to epidural lesions causing repeated acute compression of the dural tube, which can cause spinal subdural hematoma, and consider the possible coexistence of these lesions in diagnosis and strategic surgical decisions.     

Radiologic case study. Intraspinal lumbar synovial cyst

In conclusion, intraspinal lumbar synovial cysts are uncommon causes of sciatic pain. Intraspinal synovial cysts are associated with degenerative arthritis of the lumbar spine. The radiographic findings on myelography are non-specific, but CT and MRI are helpful in establishing the diagnosis and in differentiating synovial cysts from other extradural lesions.     

Congenital spinal extradural cysts,anterior sacral meningocoele and intraspinal root cysts

Summary A series of seven patients is reported, in whom various combinations of spinal extradural cysts, anterior sacral and intrasacral meningocoele and intraspinal root cysts occurred. These malformations occurring in combinations in the same patient are not true examples of dysraphism, but are due rather to weak areas of the dural covering. Such weakness leads to different manifestations depending upon the age of the patient and on whichever region of the dural sac is weak. When these cystic lesions give symptoms they should be treated operatively. If the correct diagnosis is made, the prognosis is good.     

Hemorrhagic lumbar facet cysts accompanying a spinal subdural hematoma at the same level

Context

We present a rare and interesting case of hemorrhagic lumbar facet cysts accompanying a spinal subdural hematoma at the same level suggesting a possible mechanism by which spinal subdural hematomas can arise.

Findings

A 71-year-old man presented with persistent sciatic pain and intermittent claudication. Magnetic resonance imaging demonstrated a multilocular mass lesion that showed high signal intensity in both T1- and T2-weighted images, and was located both inside and outside of the spinal canal. Computed tomographic myelography showed a cap-shaped block of the dural tube at L5 and computed tomography with L5–S facet arthrography demonstrated cystic masses. The patient was diagnosed with lumbar radiculopathy caused by hemorrhagic facet cysts, and then progressed to surgical treatment. Surgery revealed that the cysts contained blood clots, and intraoperative findings that the inside of the dural tube appeared blackish and that the dural tube was tensely ballooned after removal of the cysts led us to explorative durotomy. The durotomy demonstrated concentrated old blood pooling both in the dorsal and ventral subdural space, and these spaces were subsequently drained. After surgery, his sciatic pain and intermittent claudication resolved. There was no evidence of cyst mass recurrence at 2 years of follow-up.

Conclusion

We propose a newly described mechanism for the formation of spinal subdural hematomas. We recommend surgeons be alert to epidural lesions causing repeated acute compression of the dural tube, which can cause spinal subdural hematoma, and consider the possible coexistence of these lesions in diagnosis and strategic surgical decisions.