Greenstick fracture-hinge decompressive craniotomy in infants: illustrative case and literature review of techniques for decompressive craniotomy without bone removal.

PURPOSE: We present the potential usefulness of a greenstick fracture-hinge decompressive craniotomy, a variant of a hinge-craniotomy, as an alternative technique for use with a decompressive craniectomy (DC) in infants. A literature review of hinge-craniotomy procedures and technical variants is also provided, with a focus on complications associated with a DC peculiar to infants and children. METHODS: Illustrative case presentation along with literature review. RESULT: Significant rates of complications associated with a DC and subsequent cranioplasty have been reported, such as bone flap resorption, hydrocephalus, cerebrospinal fluid collection, and infection, especially in infants. A hinge-craniotomy is an older technique reported to have potential usefulness with some modifications, though concerns have been raised about adequate decompression and definitive indications. CONCLUSION: A DC procedure performed in children, especially infants, includes a significantly high risk of various complications; thus, a hinge-craniotomy technique is worthwhile for consideration to avoid such complications. Additional studies are required to clarify whether this technique may contribute to reduce complications related to a DC in infants and children.

Functional connectivity analysis and prediction of cognitive change after carotid artery stenting.

OBJECTIVE: The neurocognitive course of patients who have undergone cerebral revascularization has been the subject of many studies, and the reported effects of carotid artery stenting (CAS) on cognitive function have varied from study to study. The authors hypothesized that cognitive amelioration after CAS is associated with alteration of the default mode network (DMN) connectivity, and they investigated the correlation between functional connectivity (FC) of the DMN and post-CAS changes in cognitive function in order to find a clinical marker that can be used to predict the effect of cerebral revascularization on patients' cognitive function in this preliminary exploratory study. METHODS: The authors examined post-CAS changes in cognitive function in relation to FC in patients treated for unilateral carotid artery stenosis. Resting-state functional MRI (rs-fMRI) was performed with a 3-T scanner before and 6 months after CAS in 8 patients. Neuropsychological tests (Wechsler Adult Intelligence Scale III and Wechsler Memory Scale-Revised) were administered to each patient before and 6 months after CAS. The DMN was mapped for each patient through independent component analysis of the rs-fMR images, and the correlation between FC of the DMN and post-CAS change in cognitive function was analyzed on a voxel level. Multivariable regression analysis was performed to identify preoperative factors associated with a post-CAS change in cognitive function. RESULTS: Post-CAS cognitive function varied between patients and between categories of neuropsychological tests. Although there was no significant overall improvement in Working Memory scores after CAS, post-CAS Working Memory scores changed in negative correlation with changes in FC between the DMN and the precentral/superior frontal gyrus and between the DMN and the middle frontal gyrus. In addition, the preoperative FC between those areas correlated positively with the post-CAS improvement in working memory. CONCLUSIONS: FC between the DMN and working memory-related areas is closely associated with improvement in working memory after CAS. Preoperative analysis of FC of the DMN may be useful for predicting postoperative improvement in the working memory of patients being treated for unilateral stenosis of the extracranial internal carotid artery.Clinical trial registration no.: UMIN000020045 (www.umin.ac.jp/ctr/index.htm).

[Percutaneous transluminal angioplasty using a stent for an aberrant left subclavian artery stenosis with a right-sided aortic arch: a case report].

An aberrant left subclavian artery is a rare variant that has been reported to coexist with the right-sided aortic arch in many cases. We encountered a case in which percutaneous transluminal angioplasty using a stent was performed for an aberrant left subclavian artery and left carotid artery. The patient was a 63-year-old man in whom left carotid artery stenosis and abnormal flow pattern of the left vertebral artery was accidently found during an ultrasound screening of his carotid artery. The right-sided aortic arch with the aberrant left subclavian artery was revealed by a cerebral angiogram via the right femoral artery. Despite difficulty in inserting a catheter at the origin of the aberrant left artery, the treatment was completed successfully. To our knowledge, endovascular treatment for an aberrant left subclavian artery has not been reported until date.

Effect of vasodilation by milrinone, a phosphodiesterase III inhibitor, on vasospastic arteries after a subarachnoid hemorrhage in vitro and in vivo: effectiveness of cisternal injection of milrinone.

OBJECTIVE: Cerebral vasospasm remains a major cause of morbidity and mortality. Milrinone, a bipyridine phosphodiesterase III inhibitor, is a potent member of the inodilator class of cardiac agents for vasospasm and is injected intra-arterially or intracisternally. There have been no studies investigating the duration of action (context-sensitive half-life) of milrinone for vasospasm or the most effective route of administration (intra-arterial versus intracisternal). We examined the effects of intracisternal and intra-arterial injection of milrinone on chronic cerebral vasospasm in dogs. METHODS: A double-hemorrhage canine model was used. In a preliminary isometric tension study of canine vasospastic basilar arteries, the vasodilatory effects of milrinone were examined 7 days after an initial injection of blood. Milrinone was injected intracisternally (0.1 mg, 0.47 mmol/L) or intra-arterially (0.3 mg/kg, 1.2 mmol/L), and angiograms were performed 30, 60, 120, 180, 240, 300, and 360 minutes later on day 7. RESULTS: Milrinone produced concentration-dependent vasodilation and was effective intracisternally, resulting in significant dilation until 180 minutes after injection and a tendency for dilation until 240 minutes. The effect of intra-arterial injection was not as significant compared with an intracisternal injection, resulting in significant dilation only at 180 minutes after intra-arterial injection. CONCLUSION: Intracisternal injection of milrinone was more effective than intra-arterial injection for chronic cerebral vasospasm in dogs because intracisternal injection produced a higher concentration in vasospastic arteries (0.034-0.068 mmol/L intracisternally versus 0.016 mmol/L intra-arterially).

Antivasospastic and antiinflammatory effects of caspase inhibitor in experimental subarachnoid hemorrhage.

OBJECT: Inflammation in the subarachnoid space and apoptosis of arterial endothelial cells have been implicated in the development of delayed cerebral vasospasm after subarachnoid hemorrhage (SAH). The authors investigated mechanisms of possible antivasospastic effects of N-benzyl-oxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK), a caspase inhibitor that can inhibit both inflammatory and apoptotic systems, in animal models of SAH. METHODS: Rabbits were assigned to three groups of eight animals each and were subjected to SAH by injection of blood into the cisterna magna. The experiments were performed in the following groups: SA only, SAH + vehicle, and SAH + Z-VAD-FMK. The Z-VAD-FMK (1 mg) or vehicle (5% dimethyl sulfoxide) was intrathecally administered before SAH induction. Diameters of the basilar artery (BA) were measured on angiograms obtained before and 2 days after SAH. The BA diameter on Day 2 was expressed as a percentage of that before SAH. Interleukin (IL)-1 in the cerebrospinal fluid (CSF) was examined using Western blotting, and brains were immunohistochemically examined for caspase-1 and IL-1beta. In a separate experiment, 20 rats were subjected to SAH and their brains were immunohistochemically assessed for caspase-1, IL-1beta, and macrophages. RESULTS. In rabbits, Z-VAD-FMK significantly attenuated cerebral vasospasm (the BA diameter on Day 2 in SAH-only, SAH + vehicle, and SAH + Z-VAD-FMK groups was 66.6 +/- 3.2%, 66.3 +/- 3.7%, and 82.6 +/- 4.9% of baseline, respectively), and suppressed IL-1beta release into the CSF and also suppressed immunoreactivities of caspase-1 and IL-1P in macrophages infiltrating into the subarachnoid space. Immunoreactivities for caspase-1 and IL-1P were observed in immunohistochemically proven infiltrating macrophages in rats. CONCLUSIONS: These results indicate that caspase activation may be involved in the development of SAH-induced vasospasm through inflammatory reaction.

[Usefullness of intrasacral fixation in an extremely unstable lumbosacral spine].

Intrasacral fixation technique devised by Jackson is said to provide rigid lumbosacral fixation. We treated 3 cases of lumbosacral lesions using this technique in which lumbosacral segment had become extremely unstable during surgical intervention adding to the effect of original lesions. In all cases, surgeries were performed in 2 stages, intrasacral fixation and anterior stabilization. Case 1: A 52-year-old male was diagnosed fungal discitis and spondylitis at L4 and L5. X-ray showed destruction of the vertebral bodies. L2, L3 and sacrum were fixed posteriorly using the intrasacral fixation technique. One week after the first operation, L4 and L5 vertebral bodies were replaced by long fibula grafts through the extraperitoneal approach. Case 2: A 25-year-old female with cauda equina syndrome and abnormal body form diagnosed as having spondyloptosis in which the entire vertebral body of L5 had descended below the endplate of S1. MR imaging revealed marked canal stenosis at the S1 level. In the first surgery, L5 vertebral body was resected through the transperitoneal approach. After 1 week of bed rest, posterior segments of L5 were resected, L4 was affixed to the sacrum and anterior stabilization was achieved with 2 mesh cages and lumbosacral spine was fixed using the intrasacral fixation technique. Case 3: A 64-year-old female was diagnosed as having pyogenic discitis and osteomyelitis at the L5-S1 level. In spite of successful medical treatment for infection, low back pain continued. Radiologically, L5 vertebral body was shown to have collapsed and slipped anteriorly over the sacrum. L3, L4 and sacrum were fixed by intrasacral fixation. One week after the first operation, the L5/S1 disc and the suppurtive vertebral bodies were resected through the extraperitoneal approach and anterior stabilization was performed with iliac bone grafts. At follow-up for a minimum of 6 months, initial fixation was maintained in all 3 cases and bony fusion was obtained. The intrasacral fixation technique was considered to be effective for extremely unstable lumbosacral lesions.

Combined use of TruFill DCS detachable coil system and Guglielmi detachable coil for embolization of meningioma fed by branches of the cavernous internal carotid artery.

A 57-year-old female presented with a left petroclival meningioma fed by the meningohypophyseal trunk of the internal carotid artery (ICA). The enlarged tentorial marginal artery and inferior hypophyseal artery were successfully embolized with the TruFill DCS Detachable Coil System through a 0.019-inch inner diameter microcatheter. Superselective catheterization into the dorsal meningeal artery could not be achieved with the same microcatheter, because the catheter tip was too large to pass into the vessel. Subsequently the feeding artery was successfully embolized with a Guglielmi detachable coil (GDC) through a 0.016-inch inner diameter microcatheter. The patient underwent surgery without blood loss on the day after embolization. Our subjective impression was that the TruFill DCS was softer and had less resistance during insertion, whereas the GDC could be delivered through a smaller caliber system for smaller vessels. Appropriate use of the TruFill DCS and GDCs can allow efficient embolization of the feeding branches of the ICA.

[Embolization for aneurismal dilatation associated with ruptured dissecting anterior inferior cerebellar artery aneurysm with preservation of the parent artery: case report].

We report a rare case of a ruptured dissecting anterior inferior cerebellar artery (AICA) aneurysm treated by endosaccular embolization with a Guglielmi detachable coil (GDC). An 85-year-old female presented with headache. Computed tomographic (CT) scan showed subarachnoid hemorrhage and intraventricular hemorrhage in the fourth ventricule. Cerebral angiography and 3D-CT angiography revealed an aneurysmal dilatation at the anterior pontine segment of the right AICA with a diagnosis of arterial dissection. The right posterior inferior cerebellar artery (PICA) was absent and the right AICA supplied the territory normally nourished by the right PICA. The aneurismal dilatation was occluded by endosacullar embolization with preservation of the AICA. The distal AICA aneurysm is rare and only seven cases treated with endovascular embolization have been reported. In these, six cases were treated by parent artery occlusion with coil and the subsequent three cases presented with ischemic complications. Only one case was treated by endosaccular embolization with GDC. To our knowledge, this is the second report of the distal AICA aneurysm treated by endosaccular embolization with GDC. Distal AICA aneurysms are briefly discussed while reviewing the literature.

[A case of cervical endodermal cyst].

A very rare case involving an endodermal cyst of the cervical spinal canal was documented. In 1999, a 28-year-old male presented with mild tetraplegia due to a traffic accident and consequently, he was admitted to another hospital. Magnetic resonance imaging (MRI) performed at that time demonstrated a cervical cord cyst. He was treated conservatively and as a result, complete resolution of symptoms was achieved. Five years later, he presented with progressive right hemiparesis and was referred to our institute. MRI at the time of admission exhibited an intradural extramedullary cystic lesion on the ventral side of the spinal cord at the C5-6 levels, which was characterized by low intensity on T1-weighted, and by high intensity on T2-weighted images. The cyst, which had increased in size, compressed the spinal cord remarkably backward. The anterior central vertebrectomy approach was performed. Subtotal resection of the cyst wall was conducted due to its tight partical adhesion to the spinal cord. The vertebral defect was reconstructed with an autogenous iliac graft. According to histological findings the cyst wall consisted of a single layer of columnar epithelial cells with secretory granules and immunohistochemical examination revealed that the cyst wall was positive for cytokeratin 7. Symptoms improved immediately. Subsequently, the patient was discharged with good performance status. Endodermal cysts are very rare developmental cysts derived from the embryonic endodermal layer. Moreover, these lesions are usually located intradurally in the cervical and upper dorsal spine ventral to the spinal cord. Total removal of the cyst is recommended if it is possible. However, total resection is often difficult due to adhesion of the cyst wall to the neural tissue so invasive resection should be avoided. In such cases, follow-up MRI is necessary in order to exclude recurrence of the remnant lesion.

[Ruptured fenestrated aneurysm of vertebral artery union successfully treated by endovascular surgery with GDC].

It is difficult to operate on ruptured basilar artery aneurysms in the acute phase because of the anatomical complexity, brain swelling, patients' medical condition, etc., but because there is some risk of rebleeding and/or vasospasm if surgery is delayed, early surgery is recommended. We encountered a rare case of ruptured fenestrated aneurysm of the vertebral artery (VA) union, treated it safely by endovascular surgery with Guglielmi detachable coils (GDCs) in the acute phase, and obtained a good outcome after intensive care. We therefore conclude that endovascular surgery with GDCs is a first-line therapy for fenestrated aneurysms of the VA union in the acute phase after subarachnoid hemorrhage. Fenestrated aneurysms of the VA union are very rare, and long-term follow-up is mandatory.