Anesthetic management of parturients with Arnold Chiari malformation-I: a multicenter retrospective study

BackgroundConsensus regarding the safest mode of delivery and anesthetic management for parturients with Arnold Chiari malformation-I (ACM-I) remains controversial. This study assessed their anesthetic management and reported anesthetic complications during hospitalization for delivery.MethodsThis was a multicenter, retrospective, cohort study of patients with ACM-I undergoing vaginal or cesarean delivery. Data were obtained from the electronic databases of four United States academic institutions using International Classification of Diseases (ICD) codes from 2007–2017 at three sites and 2004–2017 at one site. The primary outcome was anesthetic complications.ResultsData were analyzed for 185 deliveries in 148 patients. Diagnosis of ACM-I was made prior to delivery in 147 (80%) cases. Pre-delivery neurosurgical consultation for management of ACM-I was performed in 53 (36%) patients. Pre-existing symptoms were recorded for 89 (48%) of the deliveries. Vaginal deliveries occurred in 80 (43%) cases, and 62 women (78%) received neuraxial labor analgesia. Cesarean delivery was performed in 105 (57%) cases, of which 70 women (67%) had neuraxial anesthesia and 34 (32%) received general anesthesia. Post-dural puncture headache was reported in three (2%) patients who had neuraxial anesthesia, and in two (12%) patients with syringomyelia. There was one (3%) reported case of aspiration pneumonia with general anesthesia.ConclusionsThe findings suggest that anesthetic complications occur infrequently in patients with ACM-I regardless of the anesthetic management. Although institutional preference in anesthetic and obstetric care appears to drive patient management, the findings suggest that an individualized approach has favorable outcomes in this population.     

Experimental model of chronic tonsillar herniation associated with early stage syringomyelia

This report describes an experimental model of chronic tonsillar herniation and its effects on the spinal cord. In ten rats, a small piece of chemically induced mammary cancer was transplanted to the supraoccipital bone. In all cases, the transplanted cancers grew into the posterior fossa, destroying the supraoccipital bone and compressing the cerebellum extradurally. In six of the ten rats, tonsillar herniation was observed at 8–14 weeks after transplantation. Transdural infiltration of the tumor cells was not apparent in any animal. In those rats with tonsillar herniation (n=6), the spinal cord from the C5 to the T8 segments showed enlargement of the central canal without exception. Histological examination revealed the following changes: stretching and thinning of the ependymal cells; swelling of the astrocytic processes; and extracellular edema, predominantly in the dorsal gray matter, but also in the ventral inner portion of the dorsal column. In the control group (n=4) and those rats without tonsillar herniation (n=4), such histological changes of the spinal cord were not observed. Although the lesions can not be regarded as representing mature syringomyelia, they most likely constitute an earlier evolutionary stage.     

Transjugular intrahepatic cavoportal shunt for Budd–Chiari syndrome

Budd–Chiari syndrome (BCS) is characterized by obstruction of the hepatic venous outflow tract. Therapeutic options for BCS are limited. We report a case of a 21-year-old woman with protein S and C deficiency with gross ascites. Treatment with transjugular intrahepatic portosystemic shunt (TIPS) was attempted, which revealed occluded hepatic veins, so transcaval TIPS was performed. No serious procedure-related complication occurred. After successful shunt creation, the patient's symptoms subsided and she was discharged and followed up for 6 months.     

Reversible tonsillar prolapse in vein of Galen aneurysmal malformations: report of eight cases and pathophysiological hypothesis

We report eight cases of vein of Galen aneurysmal malformation (VGAM) assoicated with a Chiari type I malformation. In four cases magnetic resonance imaging (MRI) or computed tomography performed in the neonatal period did not demonstrate the posterior fossa anomaly, which appeared on later scans. In the other cases the MRI was performed in infancy and the anomaly was already present. We compared the venous phases of the posterior fossa angiograms and the MRI in these patients. In all eight cases, the angiograms showed a reflux in the cerebellar veins, via the petrous vein, associated with a uni-or bilateral stenosis or thrombosis of the distal posterior dural sinuses. Furthermore, in two cases the posterior fossa returned to normal on MRI following endovascular treatment, while in three cases the herniation of the cerebellar tonsils decreased after the embolization. Tonsillar prolapse becomes irreversible when the venous outlet is incapable of taking the flow even when the VGAM has been treated adequately. In eight additional cases of VGAM for which MRI and angiogram studies were available and in which stenosis or thrombosis of posterior dural sinuses was present without tonsillar prolapse, no reflux into the cerebellar veins was shown. We suggest that the posterior fossa hydrovenous congestion is a result of inadequate venous drainage and that the tonsillar descent is reversible if adequate venous drainage is reconstituted following therapeutic embolization of the fistula. Tonsillar prolapse is not a consequence of mass or raised intraventricular pressure. Our observation suggests that in some other conditions, the Chiari I malformations may be secondary to early hydrovenous dysfunction of the posterior fossa.     

静脉内支撑治疗布-加综合征

目的：评估静脉内支撑治疗布－加（Ｂｕｄｄ－Ｃｈｉａｒｉ）综合征的应用价值。方法：①下腔静脉完全梗阻者,根据阻塞长度置入可扩张性内支撑架;②门静脉高压者,在下腔静脉球囊扩张的同时行颈内静脉肝内门体分流术（ＴＩＰＳＳ）治疗后再置入内支撑架;③肝静脉狭窄或闭塞者,扩张肝静脉远端后再植入内支撑架。结果：所有患者均获得操作成功。手术后临床症状明显改善,下腔静脉压差和门静脉压力显著下降。随访８例下腔静脉内支撑和肝内门体分流道通畅良好。结论：静脉内支撑治疗布－加综合征疗效良好     

后颅窝骨性扩大术治疗Chiari畸形合并脊髓空洞症

目的　介绍后颅窝骨性扩大术治疗Chiari畸形合并脊髓空洞症。方法　该手术分为两种亚术式 ,一种是枕颈固定扩大术 :取自体髂骨 5cm× 10cm ,打磨成“凹”字形。上端为齐头端 ,固定在后颅窝减压窗缘。缺口端为下端 ,固定在枢椎棘突上 ,将扩大的硬脑 (脊 )膜修补筋膜片固定在植骨片内面 ,使筋膜片贴附在植骨片内面 ,形成帐篷状 ;另一种是单纯骨性扩大术 :取自体髂骨 6cm× 8cm的梯形骨片 ,并利用较厚的髂骨缘打磨成弧形。植骨片固定在后颅窝减压窗上 ,弧形端构成枕骨大孔后缘。将扩大的硬脑 (脊 )膜修补筋膜片也固定在植骨片内面 ,使筋膜片贴附在植骨片内面 ,也形成帐篷状。结果　本组病例随访 2～ 7年 ,术后症状体征缓解总有效率为91.6% ,肌力比以前提高 2～ 3级。结论　该术式比其他治疗Chiari畸形合并脊髓空洞症的术式 ,治疗效果显著 ,疗效切实可靠     

Surgery for Syringomyelia: An Analysis Based on 163 Surgical Cases

Summary ? Object. The authors analyzed the cases of 163 patients with syringomyelia to assess the appropriate surgical procedure. Methods. Depending on the aetiological factors and treatment considerations the series was classified into three groups. Group I were cases where there was no definite demonstrable aetiological factor; Group II cases had basilar invagination and/or Chiari malformation; and Group III consisted of cases where the syrinx was secondary to an obvious aetiology, such as a mass lesion either in the posterior cranial fossa or in the spine or a severe kyphotic spinal deformity. Post-traumatic syringomyelia and syrinx in association with spina bifida were not studied. Conclusions. We concluded that for Group I cases syringosubarachnoid shunting is the ideal form of treatment. In Group II cases foramen magnum bony decompression is satisfactory and physiological. Good results were obtained even in cases where either a foramen magnum decompression alone or in combination with a syringo-subarachnoid shunt was done. Only syringosubarachnoid shunt (without a foramen magnum decompression) in Group II cases was found to produce poor outcome. Group III cases should be treated for the primary aetiological problem. Only syrinx drainage procedure without treatment of aetiology in these cases produced poor results. It was observed that clinical outcome rather than radiological improvement is the reliable indicator of the surgical result.     

New Association between Idiopathic Scoliosis and Luckenschadel Skull (Lacunar Skull)

ObjectiveLuckenschadel skull is a skull that is radiologically characterized by lacunae in the cranial vault. To date, although the association between neurological abnormalities and scoliosis is well recognized, no relationship between idiopathic scoliosis and a lacunar skull has been defined. We explored the incidence and time courses of lacunar skulls in patients with idiopathic scoliosis.Materials and MethodsSpinal X-rays of 3,170 children aged 6–16 years with idiopathic scoliosis evaluated from October 2010 to August 2020 were examined for the presence of an irregular inner calvarial table indicative of a Luckenschadel skull. A total of 1,760 (55.5%) of the 3,170 images included the skull. We also explored the frequency of intraspinal abnormalities in children with lacunar skull images who underwent spinal magnetic resonance imaging.ResultsThe study population consisted of 1,760 children, 1,203 girls (68.4%) and 557 (31.6%) boys. A total of 268 (15.2%) clearly evidenced lacunar skulls in their radiographs; 186 (69.4%) girls (11.3 ± 4.3 years) and 82 (30.6%) boys (12.6 ± 3.3 years). Two of the 56 patients (3.6%) who underwent spinal MRI had intraspinal abnormalities (isolated Chiari malformation-I). No additional neurological problems were detected in children with lacunar skulls.ConclusionWe conclude that the lacunar skull is very common in children with idiopathic scoliosis who lack any other neurological pathology. The lacunar skull does not disappear even in adolescence. Although previous publications have stated that lacunar skull disappears over time in radiographic images, we observed that it became more noticeable over time in children with scoliosis.