Kosuke Kondo

Anatomical Reproducibility of a Head Model Molded by a Three-dimensional Printer

We prepared rapid prototyping models of heads with unruptured cerebral aneurysm based on image data of computed tomography angiography (CTA) using a three-dimensional (3D) printer. The objective of this study was to evaluate the anatomical reproducibility and accuracy of these models by comparison with the CTA images on a monitor. The subjects were 22 patients with unruptured cerebral aneurysm who underwent preoperative CTA. Reproducibility of the microsurgical anatomy of skull bone and arteries, the length and thickness of the main arteries, and the size of cerebral aneurysm were compared between the CTA image and rapid prototyping model. The microsurgical anatomy and arteries were favorably reproduced, apart from a few minute regions, in the rapid prototyping models. No significant difference was noted in the measured lengths of the main arteries between the CTA image and rapid prototyping model, but errors were noted in their thickness (p < 0.001). A significant difference was also noted in the longitudinal diameter of the cerebral aneurysm (p < 0.01). Regarding the CTA image as the gold standard, reproducibility of the microsurgical anatomy of skull bone and main arteries was favorable in the rapid prototyping models prepared using a 3D printer. It was concluded that these models are useful tools for neurosurgical simulation. The thickness of the main arteries and size of cerebral aneurysm should be comprehensively judged including other neuroimaging in consideration of errors.

A neurosurgical simulation of skull base tumors using a 3D printed rapid prototyping model containing mesh structures.

BackgroundDeep regions are not visible in three-dimensional (3D) printed rapid prototyping (RP) models prepared from opaque materials, which is not the case with translucent images. The objectives of this study were to develop an RP model in which a skull base tumor was simulated using mesh, and to investigate its usefulness for surgical simulations by evaluating the visibility of its deep regions.MethodsA 3D printer that employs binder jetting and is mainly used to prepare plaster models was used. RP models containing a solid tumor, no tumor, and a mesh tumor were prepared based on computed tomography, magnetic resonance imaging, and angiographic data for four cases of petroclival tumor. Twelve neurosurgeons graded the three types of RP model into the following four categories: ‘clearly visible,’ ‘visible,’ ‘difficult to see,’ and ‘invisible,’ based on the visibility of the internal carotid artery, basilar artery, and brain stem through a craniotomy performed via the combined transpetrosal approach. In addition, the 3D positional relationships between these structures and the tumor were assessed.ResultsThe internal carotid artery, basilar artery, and brain stem and the positional relationships of these structures with the tumor were significantly more visible in the RP models with mesh tumors than in the RP models with solid or no tumors.ConclusionsThe deep regions of PR models containing mesh skull base tumors were easy to visualize. This 3D printing-based method might be applicable to various surgical simulations.

Basal encephalocele in an adult patient presenting with minor anomalies: a case report

IntroductionBasal encephalocele is rare in adults. Congenital and acquired cases have been reported with regard to the developmental mechanism, and the pathology has not been elucidated in detail.Case presentationWe encountered an adult with basal encephalocele strongly suggesting congenital development because of the presence of minor anomalies: strabismus and ocular hypertelorism. The disease manifested as persistent spontaneous cerebrospinal fluid rhinorrhea and repeated meningitis in a 66-year-old Japanese man. On computed tomography, brain tissue protruded through a part of the ethmoid bone of his right anterior skull base, and it was diagnosed as transethmoidal-type basal encephalocele. Regarding his facial form, the distance between his bilateral eyeballs was large compared to his facial width, and his canthal index (defined as inner to outer inter canthal ratiou2009×u2009100) was calculated as 38.5, based on which it was judged as ocular hypertelorism. In addition, his right eyeball showed strabismus. A right frontotemporal craniotomy was performed for spontaneous cerebrospinal fluid rhinorrhea, and the defective dura mater region was patched with temporal fascia.ConclusionsMild minor anomalies that require no treatment are overlooked in adults, but the presence of several anomalies increases the possibility of congenital disease. Therefore, it may be necessary to examine minor anomalies in cases of adult basal encephalocele when considering the possibility that the disease may be congenital.

Hydroperoxide in Internal Jugular Venous Blood Reflects Occurrence of Subarachnoid Hemorrhage-Induced Delayed Cerebral Vasospasm

BACKGROUNDnTo investigate the association between subarachnoid hemorrhage-induced delayed cerebral vasospasm (DCVS) and oxidative stress, an oxidation product, hydroperoxide, was measured in 3 specimens: peripheral arterial blood, cerebrospinal fluid (CSF), and internal jugular venous blood (IJVB).nnnMETHODSnHydroperoxide was measured using the diacron reactive oxygen metabolites (d-ROMs) test. The hydroperoxide levels were evaluated based on the rate of change in the d-ROMs test value on day 6 relative with that on day 3 (d-ROMs change rate).nnnRESULTSnThe subjects were 20 patients. The d-ROMs change rate in IJVB was significantly higher in patients with DCVS on day 6 than in those without it (P < .01). When the patients were classified into the following 3 groups: Group A (no DCVS occurred throughout the clinical course); Group B (DCVS occurred, but no cerebral infarction [CI] was induced); and Group C (DCVS occurred and caused CI), the d-ROMs change rate in IJVB was the highest in Group C, followed by Group B then A (P < .01). The d-ROMs change rates in peripheral arterial blood and CSF were not related to the development of DCVS.nnnCONCLUSIONSnIt was concluded that the more severe DCVS occurs and is more likely to progress to CI as the IJVB hydroperoxide level rises early after the development of subarachnoid hemorrhage.

Clinical Characteristics of Subarachnoid Hemorrhage with an Intracerebral Hematoma and Prognostic Factors

BACKGROUNDnSubarachnoid hemorrhage (SAH) with an intracerebral hematoma (ICH) shows an unfavorable prognosis. In the present study, we examined the characteristics of SAH with ICH and its prognosis.nnnMETHODSnSubjects comprised 218 patients with SAH who underwent surgery between January 2007 and December 2015. We compared age, sex, the location of the aneurysm, treatment procedures, medical history (hypertension, diabetes, and heart disease), the Glasgow Coma Scale (GCS) score on admission, rerupture rate, hydrocephalus, the diameter of the aneurysm, cerebral vasospasm, perioperative cardiopulmonary complications, and the Glasgow Outcome Scale (GOS) score after 2 months between patients with SAH with and without ICH. The interval from the onset of SAH until surgery, the location of ICH, and hematoma volume were investigated as prognostic factors for SAH with ICH.nnnRESULTSnAmong all subjects, 82 had SAH with ICH. GCS scores on admission were poorer in patients with SAH with ICH than in those without ICH (Pu2009<u2009.001), and middle cerebral artery aneurysms were more likely to form hematomas (Pu2009<u2009.001). GOS scores after 2 months were also poorer in patients with SAH with ICH (Pu2009<u2009.01). The size of aneurysms was larger in the 82 patients with SAH with ICH than in those without ICH (Pu2009<u2009.001), and the rerupture rate was higher (Pu2009<u2009.001). The unfavorable prognosis of patients with SAH with ICH was associated with age and GCS score on admission.nnnCONCLUSIONSnA young age and a favorable GCS score on admission may be associated with a favorable prognosis for patients with SAH with ICH, and SAH with ICH may easily rerupture.

Comparison between Quantitative Stiffness Measurements and Ultrasonographic Findings of Fresh Carotid Plaques

Using a stiffness meter, we quantitatively measured the stiffness of fresh plaques that had been excised by carotid endarterectomy. The objective of this study was to clarify the correlation between plaque stiffness and pre-operative carotid ultrasonographic findings, and predict the stiffness of plaques before surgery by comparison with the stiffness of common items. The study population comprised 44 patients (44 lesions) who had undergone carotid endarterectomy at our institution between December 2009 and October 2014. The stiffness of excised fresh plaques was measured using a stiffness meter and compared with the pre-operative echographic findings for the plaques and the stiffness of selected foods and common items. The mean stiffness value for all plaques was 4.52xa0±xa03.30xa0MPa (meanxa0±xa0standard deviation). The plaques exhibiting calcification were significantly harder (pxa0=xa00.001). On classification of lesions on the basis of echographic findings, plaque hardness was in the order low-echoic (15 lesions)xa0<xa0iso-echoic (20 lesions)xa0<xa0high-echoic (9 lesions) (pxa0=xa00.02). The stiffness of the low-echoic group was equivalent to that of tofu or sliced cheese, whereas the plaques in the iso- and high-echoic groups exhibited stiffness similar to that of ham and a plastic eraser, respectively. A significant correlation was observed between the quantitative stiffness values of carotid plaques and their brightness on carotid ultrasonography. Using these data, operators might be able to predict plaque stiffness from pre-operative echographic findings. In addition, it might be useful for operators to compare such quantitative stiffness measurements with stiffness data for foods and common items to gain an understanding of the state of the target plaque before treatment.

Risk Factors Association with Severity of White Matter Lesions on MagneticResonance Imaging

Background: The objective of this study was to identify risk factors involved in the severity of deep subcortical white matter (DSWMH) and periventricular (PVH) hyper-intensities on MRI, which are white matter lesions. nMethods: The subjects were 506 consecutive asymptomatic patients examined in a brain dry-dock. The severities of DSWMH and PVH were classified using the Fazekas scale. Regarding risk factors, in addition to sex, age, cigarette smoking, alcohol drinking, and renal function, hypertension, diabetes, dyslipidemia, and gout were divided into 3 grades: without the disease, being treated, or untreated, and evaluated. nResults: Regarding the normal group as grade 0 on the Fazekas scale, the relationship between the DSWMH severity and each risk factor was investigated. In addition to an increase with aging (p<0.001), the DSWMH severity increased in the order of the state of hypertension from without the disease, being treated, or untreated (p<0.01). The PVH severity increased with aging (p<0.001) and in the order of the state of diabetes mellitus from without the disease, being treated, or untreated (p<0.001). nConclusion: Strict treatment of each disease may prevent aggravation of DSWMH and PVH, respectively, reducing incidences of stroke and dementia in the future.

Operative simulation of anterior clinoidectomy using a rapid prototyping model molded by a three-dimensional printer

BackgroundAs the anatomical three-dimensional (3D) positional relationship around the anterior clinoid process (ACP) is complex, experience of many surgeries is necessary to understand anterior clinoidectomy (AC). We prepared a 3D synthetic image from computed tomographic angiography (CTA) and magnetic resonance imaging (MRI) data and a rapid prototyping (RP) model from the imaging data using a 3D printer. The objective of this study was to evaluate anatomical reproduction of the 3D synthetic image and intraosseous region after AC in the RP model. In addition, the usefulness of the RP model for operative simulation was investigated.MethodsThe subjects were 51 patients who were examined by CTA and MRI before surgery. The size of the ACP, thickness and length of the optic nerve and artery, and intraosseous length after AC were measured in the 3D synthetic image and RP model, and reproducibility in the RP model was evaluated. In addition, 10 neurosurgeons performed AC in the completed RP models to investigate their usefulness for operative simulation.ResultsThe RP model reproduced the region in the vicinity of the ACP in the 3D synthetic image, including the intraosseous region, at a high accuracy. In addition, drilling of the RP model was a useful operative simulation method of AC.ConclusionsThe RP model of the vicinity of ACP, prepared using a 3D printer, showed favorable anatomical reproducibility, including reproduction of the intraosseous region. In addition, it was concluded that this RP model is useful as a surgical education tool for drilling.

Ruptured Aneurysm of the Superior Cerebellar Artery Associated With Cerebellar Hemangioblastoma: A Case Report and Review of Literature

Aneurysms associated with hemangioblastoma are very rare. We encountered a patient in whom an aneurysm of the distal superior cerebellar artery, the main feeding vessel of cerebellar hemangioblastoma, ruptured and caused hemorrhage. On the basis of the computed tomography findings, the superior cerebellar artery aneurysm was identified as the source of hemorrhage, and embolization using a Guglielmi detachable coil was performed in subsequent endovascular surgery. Endovascular embolization was applied to the artery feeding the tumor at 4 weeks after admission, and the tumor was removed using an occipital transtentorial approach. A favorable therapeutic outcome may be expected when using a combination of endovascular therapy and surgical craniotomy for aneurysms associated with hemangioblastoma.

P1-41. Verification of stimulation site in bulbocavernous reflex (BCR) monitoring

Bulbocavernosus reflex (BCR) monitoring is useful for lumbar and cauda surgery. However, in some cases BCR may be difficult to record. We report verification of the stimulation site of BCR monitoring. The subjects were 24 patients undergoing BCR monitoring from 2010 to 2015 (0–79xa0years old, 14 males, 10 females). In all cases, BCR was recorded from the needle electrode of the anal sphincter. An adult male stimulated the dorsal side of the penis. The boy stimulated the dorsal and ventral side of the penis. Women were classified into three types: clitoral and labia stimulation, left and right side stimulation of the clitoris, clitoris and pubis stimulation. An adult male was able to record in all cases. An adult female could record with a type that stimulated the clitoris and labia. Childhood cases were difficult to record in all cases. Women’s BCR stimulation needs to directly stimulate the clitoris. Children may be involved in neuropathy due to congenital diseases or underdeveloped nerve.