bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recurrent ganglion cyst of the peroneal nerve: radiological and operative observations
Authors: Dubuisson Annie S. , Stevenaert Achille 
Published: June 2009

✓ This 34-year-old man presented with right leg pain and foot drop of 1-month duration. The preoperative diagnosis of a 10-cm-long ganglion cyst of the peroneal nerve was achieved using ultrasonography (US), computerized tomography and, particularly magnetic resonance (MR) imaging. Surgical exploration disclosed a lobulated cystic mass filled with gelatinous material, which intermingled with the nerve substance of the deep peroneal nerve. The lesion was completely resected, with the sacrifice of some electrically nonfunctioning fascicles. No connection with the knee joint was found. A good postoperative recovery of motor function was obtained. However, routine postoperative MR imaging disclosed a recurrent ganglion cyst that was slightly less extensive than the original. A careful radiological examination of the knee joint was performed, including arthrography. A communication of the cyst with the tibiofibular joint was clearly demonstrated and was meticulously closed at reoperation. The patient's postoperative course was uneventful, and a third MR image, obtained 5 months after reoperation, showed no sign of cyst recurrence. The patient remained free of symptoms 11 months postoperatively.
This case illustrates the value of US and MR in diagnostic imaging. The diagnostic efficacy of US and MR imaging in identifying and characterizing a ganglion cyst is described. Close contact between a ganglion cyst and the tibiofibular joint should raise the possibility of an existing cyst—joint communication and lead to an aggressive radiological workup and/or a surgical search for such a communication.
Superior cervical ganglion regenerating axons through peripheral nerve grafts and reversal of behavioral deficits in hemiparkinsonian rats
Authors: Pallini Roberto , Fernandez Eduardo , Lauretti Liverana , Dell'Anna Elisabetta , Marca Frank La , Gangitano Carlo , Fà Aurora Del , Olivieri-Sangiacomo Corrado , Sbriccoli Alessandro , Rossi Gian Franco 
Published: June 2009

✓ The superior cervical ganglion (SCG) has been grafted to the brain of adult rats in an attempt to reverse the parkinsonian syndrome that follows destruction of central dopamine systems. However, the main limitation to this approach is the massive cell death that occurs in the grafted SCG after direct transplantation into the brain.
In adult rats, 6-hydroxydopamine (6-OHDA) was stereotactically injected into the right substantia nigra (SN). One month later, dopamine denervation was assessed using the apomorphine-induced rotational test. In rats with a positive test, an autologous peripheral nerve (PN) graft was tunneled from the right cervical region to the ipsilateral parietal cortex. One end of the PN graft was sutured to the transected postganglionic branch of the SCG and the other end was inserted into a surgically created cortical cavity. The apomorphine test was repeated at 3 days and again at 1, 3, and 5 months after surgery. The brain, SCG, and PN graft were studied under light and electron microscopy and with the tyrosine hydroxylase immunohistochemical and horseradish peroxidase tracing methods.
Three days after grafting, there were no significant differences on the apomorphine test as compared to the preoperative test. Conversely, 1, 3, and 5 months after grafting, the number of rotations was reduced by 69% (± 20.2), 66.6% (± 17.1), and 72.5% (± 11.3), respectively. Control rats that received a free PN graft to the brain and underwent section of the postganglionic branch of the SCG did not show significant changes on the apomorphine test after surgery. Histological examination revealed that the PN graft was mostly reinnervated by amyelinic axons of small caliber. Approximately 40% of the SCG neuronal population that normally projects to the postganglionic branch survived axotomy and regenerated the transected axons into the PN graft. Axons arising from the SCG elongated the whole length of the graft, crossed the graft—brain interface and extended into brain regions adjacent to the denervated striatum up to 2037 µm from the graft insertion site.
This work shows that the ingrowth of catecholamine-regenerating axons from the SCG to dopamine-depleted brain parenchyma significantly reduces behavioral abnormalities in hemiparkinsonian rats. This effect cannot be ascribed either to the brain cavitation or to the PN tissue placement in the brain.
The significance of bacteriologically positive ventriculoperitoneal shunt components in the absence of other signs of shunt infection
Authors: Steinbok Paul , Cochrane D. Douglas , Kestle John R. W. 
Published: June 2009

✓ The purpose of this study was to determine the significance of “asymptomatic bacteriological shunt contamination” (ABSC), defined as a positive bacteriological culture found on a ventricular shunt component in the absence of bacteria in the cerebrospinal fluid (CSF) culture and/or clinical evidence of infection.
Of 174 ventriculoperitoneal shunt revisions, 19 cases of ABSC were identified and reviewed retrospectively. In all but one case, no antibiotic medications were instituted because of the positive bacteriological culture. The most common infecting organisms were coagulase-negative staphylococci (seven) and propionibacteria (eight). A comparison of the 19 study cases with the authors' overall shunt experience, as documented in the British Columbia's Children's Hospital shunt database for the time period of the study, lead the authors to suggest that ABSC was not of significance in causing the shunt failure at which contamination was identified and, more importantly, did not increase the risk of future shunt malfunction.
The results of this study indicate that in the absence of clinical evidence of shunt infection or a positive bacteriological culture from CSF, bacteria in a shunt component removed at revision in a child almost always represents a contaminant that may be ignored. Therefore, the authors advise that routine culture of shunt components removed at revision of a shunt is not indicated.
Risks in using siphon-reducing devices in adult patients with normal-pressure hydrocephalus: bench test investigations with Delta valves
Authors: Hassan Mahmood , Higashi Sotaro , Yamashita Junkoh 
Published: June 2009

✓ To elucidate the reason for malfunction of Delta valves in patients with normal-pressure hydrocephalus, the authors applied a new concept of the bench test and simulated intracranial pressure (ICP) to measure the resultant flow with a complete shunt system. Subcutaneous pressure on the valve, valve implantation site, and postural hydrostatic differentialpressure changes were simulated in this bench test designed for adult patients with normal-pressure hydrocephalus. Subcutaneous pressure ranged within 6.4 ± 0.9 cm H2O (mean ± standard deviation) on the 7th day after the implantation of the valve in rats. A linear correlation between valve closing pressures and the external pressure was observed: gradual increase of the latter resulted in an approximately equal rise in the closing pressure. Closing pressure ranged within the physiological variation of ICP (10 ± 5 cm H2O) in the supine position. In the erect position it was higher than the physiological variation (+5 to −5 cm H2O) when the valve was placed at the level of the foramen of Monro and lower when placed at the level of the clavicle. This observation indicates that the subcutaneous pressure around the Delta valve significantly affects its closing pressure. An excessive reduction of flow or a functional obstruction occurs when the patient with a Delta valve implanted at the foramen of Monro assumes an erect posture.
The authors conclude that Delta valves are not recommended for implantation at the level of the foramen of Monro in patients with normal-pressure hydrocephalus because of the risk of underdrainage. The mastoid process or clavicle may be the alternative levels for its implantation to prevent underdrainage; however, the possibility of shunt malfunction should be kept in mind because subcutaneous pressure is variable among patients and that might affect the performance characteristics of these valves.
Postoperative surveillance imaging in children with cerebellar astrocytomas
Authors: Sutton Leslie N. , Cnaan Avital , Klatt Laura , Zhao H. , Zimmerman Robert , Needle Michael , Molloy Patricia , Phillips Peter 
Published: June 2009

✓ The standard follow-up care for children with cerebellar astrocytomas includes regular surveillance imaging of the brain with computerized tomography or magnetic resonance. The purpose of surveillance imaging is to detect asymptomatic tumor recurrence at an early stage and permit safer reoperation. The authors evaluated the effectiveness of an intensive surveillance program for cerebellar astrocytoma and tested different models of surveillance frequency and duration to arrive at a specific recommended program.
Review of the records of 93 children with typical cerebellar astrocytomas who received follow-up care between 1975 and 1993 was performed. Immediate postoperative and surveillance images were classified as showing definite, equivocal, or no tumor based on the radiology report at the time the image was obtained. Various surveillance models were then tested for their predictive value for detecting tumor recurrence.
Seventeen (18%) of the 93 children had tumor recurrence or progression. Eleven of these tumors were asymptomatic and detected only by surveillance image. Tumor recurred in only one patient with a total resection, whereas tumor progression occurred in five of 21 patients with equivocal postoperative images and in 11 of 14 patients with residual tumor. A model in which patients with possible or definite residual tumor after surgery undergo surveillance at 12, 18, 30, 42, and 66 months, and later have one additional image, yielded optimum predictive value for recurrence and/or progression with the fewest images. Patients with tumor recurrence were satisfactorily treated, and only one patient died.
Children with totally resected cerebellar astrocytomas do not appear to benefit from routine surveillance, because the likelihood of recurrence is small. Surveillance is of benefit in those who may have subtotal resection based on the immediate postoperative imaging.
Use of intraoperative ultrasound for localizing tumors and determining the extent of resection: a comparative study with magnetic resonance imaging
Authors: Hammoud Maarouf A. , Ligon B. Lee , Elsouki Rabih , Shi Wei Ming , Schomer Donald F. , Sawaya Raymond 
Published: June 2009

✓ A prospective study of 70 patients with intraparenchymal brain lesions (36 gliomas and 34 metastases) was performed to evaluate the efficacy of intraoperative ultrasound (IOUS) in localizing and defining the borders of tumors and in assessing the extent of their resection. Eighteen of the 36 glioma patients had no previous therapy. All of these 18 tumors were well localized by IOUS; margins were well defined in 15 and moderately defined in three. The extent of resection was well defined on IOUS in all 18 patients, as confirmed by measurements taken on postoperative magnetic resonance (MR) images (p = 0.90). The remaining 18 patients with gliomas had undergone previous surgery and/or radiation therapy; five had recurrent tumors and 13 had radiation-induced changes. The extent of resection of the recurrent tumors was well defined in all but one patient, as confirmed by postoperative MR imaging. The extent of resection was poorly defined in all 13 patients whose pathology showed radiation effects. All 34 metastatic lesions were well localized and had well-defined margins. In addition, IOUS accurately determined the extent of resection in all cases; the results were confirmed with postoperative MR imaging.
In conclusion, IOUS is not only helpful in localizing and defining the margins of gliomas and metastatic brain lesions, it also accurately determines the extent of resection, as confirmed by postoperative MR imaging. This assessment does not apply, however, when the lesion is due primarily to radiation effect.
Surgery versus radiosurgery in the treatment of brain metastasis
Authors: Bindal Ajay K. , Bindal Rajesh K. , Hess Kenneth R. , Shiu Almon , Hassenbusch Samuel J. , Shi Wei Ming , Sawaya Raymond 
Published: June 2009

✓ Surgery and radiosurgery are effective treatment modalities for brain metastasis. To compare the results of these treatment modalities, the authors followed 31 patients treated by radiosurgery and 62 patients treated by surgery who were retrospectively matched. Patients were matched according to the following criteria: histological characteristics of the primary tumor, extent of systemic disease, preoperative Karnofsky Performance Scale score, time to brain metastasis, number of brain metastases, and patient age and sex. For patients treated by radiosurgery, the median size of the treated lesion was 1.96 cm3 (range 0.41–8.25 cm3) and the median dose was 20 Gy (range 12–22 Gy). The median survival was 7.5 months for patients treated by radiosurgery and 16.4 months for those treated by surgery; this difference was found to be statistically significant using both univariate (p = 0.0018) and multivariate (p = 0.0009) analyses. The difference in survival was due to a higher rate of mortality from brain metastasis in the radiosurgery group than in the surgery group (p < 0.0001) and not due to a difference in the rate of death from systemic disease (p = 0.28). Log-rank analysis showed that the higher mortality rate found in the radiosurgery group was due to a greater progression rate of the radiosurgically treated lesions (p = 0.0001) and not due to the development of new brain metastasis (p = 0.75).
On the basis of their data, the authors conclude that surgery is superior to radiosurgery in the treatment of brain metastasis. Patients who undergo surgical treatment survive longer and have a better local control. The data lead the authors to suggest that the indications for radiosurgery should be limited to surgically inaccessible metastatic tumors or patients in poor medical condition. Surgery should remain the treatment of choice whenever possible.
Alpha-1—antitrypsin phenotypes among patients with intracranial aneurysms
Authors: Schievink Wouter I. , Katzmann Jerry A. , Piepgras David G. , Schaid Daniel J. 
Published: June 2009

✓ A deficiency of α1-antitrypsin has been implicated in the development of arterial aneurysms, including intracranial aneurysms. The authors determined the prevalence of α1-antitrypsin deficiency of different phenotypes in 100 consecutive patients with intracranial aneurysms and compared the distribution of α1-antitrypsin phenotypes to that in the general population (904 people).
The study population consisted of 44 men and 56 women with a mean age of 52 years (range 15–81 years). The heterozygous α1-antitrypsin deficiency states (PiMS and PiMZ) were more common in patients (16%) than in the general population (7%), providing an odds ratio of 2.56 (95% confidence interval (CI) 1.32–4.75; p = 0.005). In addition, one patient (1%) was homozygous for the deficient allele (PiZZ) compared to an expected number of 0.015, providing an odds ratio of 67.0 (95% CI 2.0–363.3; p = 0.015). These findings lead the authors to suggest that the heterozygous and homozygous α1-antitrypsin deficiency states are genetic risk factors for the development of intracranial aneurysms.
Surgical resection of large incompletely treated intracranial arteriovenous malformations following stereotactic radiosurgery
Authors: Steinberg Gary K. , Chang Steven D. , Levy Richard P. , Marks Michael P. , Frankel Ken , Marcellus Mary 
Published: June 2009

✓ Although radiosurgery is effective in obliterating small arteriovenous malformations (AVMs), it has a lower success rate for thrombosing larger AVMs. The authors surgically resected AVMs from 33 patients ranging in age from 7 to 64 years (mean 30.4 years) 1 to 11 years after radiosurgery. Initial AVM volumes were 0.8 to 117 cm3 (mean 21.6 cm3), and doses ranged from 4.6 to 45 GyE (mean 21.2 GyE). Of 27 AVMs in eloquent or critical areas, 10 were located in language, motor, sensory, or visual cortex, 11 in the basal ganglia/thalamus, one each in the brainstem, hypothalamus, and cerebellum, and three in the corpus callosum. Venous drainage was deep in 13, superficial in 12, or both in eight lesions. Spetzler—Martin grades were II in one, III in 12, IV in 16, and V in four patients. Eight patients experienced rebleeding after radiosurgery but prior to surgery. Three patients developed radiation necrosis and 25 underwent endovascular embolization prior to surgery.
At surgery the AVMs were found to be markedly less vascular, partially thrombosed, and more easily resected, compared to those seen in patients who had not undergone radiosurgery. Pathological investigation showed endothelial proliferation with hyaline and calcium in vessel walls. There was partial or complete thrombosis of some AVM vessels and evidence of vessel and brain necrosis in many cases. Complete resection was achieved in 28 patients and partial resection in five. Clinical outcome was excellent or good in 31 cases, and two patients died of rebleeding from residual AVM. Four patients' conditions worsened following microsurgical resection. Final clinical outcome was largely related to the pretreatment grade. Radiosurgery several years prior to open microsurgery may prove to be a useful adjunct in treating unusually large and complex AVMs.
A fatal, chronically growing basilar artery: a new type of dissecting aneurysm
Authors: Mizutani Tohru 
Published: June 2009

✓ A long-term follow-up study (minimum duration 2 years) was made of 13 patients with tortuous dilated basilar arteries. Of these, five patients had symptoms related to the presence of such arteries. Symptoms present at a very early stage included vertebrobasilar insufficiency in two patients, brainstem infarction in two patients, and left hemifacial spasm in one patient. Initial magnetic resonance (MR) imaging in serial slices of basilar arteries obtained from the five symptomatic patients showed an intimal flap or a subadventitial hematoma, both of which are characteristic of a dissecting aneurysm. In contrast, the basilar arteries in the eight asymptomatic patients did not show particular findings and they remained clinically and radiologically silent during the follow-up period. All of the lesions in the five symptomatic patients gradually grew to fantastic sizes, with progressive deterioration of the related clinical symptoms. Dilation of the basilar artery was consistent with hemorrhage into the “pseudolumen” within the laminated thrombus, which was confirmed by MR imaging studies.
Of the five symptomatic patients studied, two died of fatal subarachnoid hemorrhage (SAH) and two of brainstem compression; the fifth patient remains alive without neurological deficits. In the three patients who underwent autopsy, a definite macroscopic double lumen was observed in both the proximal and distal ends of the aneurysms within the layer of the thickening intima. Microscopically, multiple mural dissections, fragmentation of internal elastic lamina (IEL), and degeneration of media were diffusely observed in the remarkably extended wall of the aneurysms. The substantial mechanism of pathogenesis and enlargement in the symptomatic, highly tortuous dilated artery might initially be macroscopic dissection within a thickening intima and subsequent repetitive hemorrhaging within a laminated thrombus in the pseudolumen combined with microscopic multiple mural dissections on the basis of a weakened IEL.
The authors note and caution that symptomatic, tortuous dilated basilar arteries cannot be overlooked because they include a group of malignant arteries that may grow rapidly, resulting in a fatal course.
Treatment of aneurysms by excision or trapping with arterial reimplantation or interpositional grafting
Authors: Lee Sang Youl , Sekhar Laligam N. 
Published: June 2009

✓ The authors report three cases of ruptured, large or giant aneurysms that were treated by excision or trapping, followed by revascularization of distal vessels by means of arterial reimplantation or superficial temporal artery interpositional grafting.
In the first case, a large serpentine aneurysm arising from the anterior temporal branch of the right middle cerebral artery (MCA) was excised and the distal segment of the anterior temporal artery was reimplanted into one of the branches of the MCA. In the second case, a giant aneurysm, fusiform in shape, arose from the rolandic branch of the MCA. This aneurysm was totally excised and the M3 branch in which it had been contained was reconstructed with an arterial interpositional graft. In the third case the patient, who presented with a subarachnoid hemorrhage, had a dissecting aneurysm that involved the distal portion of the left vertebral artery. In this case the posterior inferior cerebellar artery (PICA) arose from the wall of the aneurysm and coursed onward to supply the brainstem. This aneurysm was managed by trapping and the PICA was reimplanted into the ipsilateral large anterior inferior cerebellar artery. None of the patients suffered a postoperative stroke and all recovered to a good or excellent postoperative condition.
These techniques allowed complete isolation of the aneurysm from the normal blood circulation and preserved the blood flow through the distal vessel that came out of the aneurysm. These techniques should be considered as alternatives when traditional means of cerebral revascularization are not feasible.
The anatomical suitability of the C1–2 complex for transarticular screw fixation
Authors: Paramore Christopher G. , Dickman Curtis A. , Sonntag Volker K. H. 
Published: June 2009

✓ Posterior transarticular screw fixation of the C1–2 complex has become an accepted method of rigid internal fixation for patients requiring posterior C1–2 fusion. The principal limitation of this procedure is the location of the vertebral artery, because an anomalous position may prohibit screw placement. In this study, a consecutive series of computerized tomography (CT) scans was reviewed, and the suitability of each patient for transarticular screw fixation was evaluated.
All of the fine-slice axial C1–2 CT scans and reconstructions performed on a spiral scanner over 2 years were reviewed. A novel screw trajectory reconstruction was designed to visualize the potential path of a transarticular screw in the plane of the reconstruction. Scans were reviewed for bone anatomy and the position of the transverse foramen.
Seventeen (18%) of 94 patients had a high-riding transverse foramen on at least one side of the C-2 vertebra that would prohibit the placement of transarticular screws. The left side was involved in nine patients and the right in five. Three patients had bilateral anomalies. The mean age of the group with anomalies (35.9 years, range 10–76) was not significantly different from the overall mean age (35.7 years, range 6–94). An additional five patients (5%) were considered to have anatomy in which screw placement was feasible but risky. On the basis of these data, it is postulated that 18% to 23% of patients may not be suitable candidates for posterior C1–2 transarticular screw fixation on at least one side.