Real Stiffness and Vividness Reproduction of Anatomic Structures Into the 3-Dimensional Printed Models Contributes to Improved Simulation and Training in Skull Base Surgery.

BACKGROUND: Despite the advancement of 3-dimensional (3D) printing technology with medical application, its neurosurgical utility value has been limited to understanding the anatomy of bones, lesions, and their surroundings in the neurosurgical field. OBJECTIVE: To develop a 3D printed model simulating the surgical technique applied in skull base surgery (SBS), especially to reproduce visually the surgical field together with the mechanical properties of tissues as perceived by the surgeon through procedures performance on a model. METHODS: The Young modulus representing the degree of stiffness was measured for the tissues of anesthetized animals and printing materials. The stiffness and vividness of models were adjusted appropriately for each structure. Empty spaces were produced inside the models of brains, venous sinuses, and tumors. The 3D printed models were created in 7 cases of SBS planned patients and were used for surgical simulation. RESULTS: The Young modulus of pig's brain ranged from 5.56 to 11.01 kPa and goat's brain from 4.51 to 13.69 kPa, and the dura of pig and goat values were 14.00 and 24.62 kPa, respectively. Although the softest printing material had about 20 times of Young modulus compared with animal brain, the hollow structure of brain model gave a soft sensation resembling the real organ and was helpful for bridging the gap between Young moduli values. A dura/tentorium-containing model was practical to simulate the real maneuverability at surgery. CONCLUSION: The stiffness/vividness modulated 3D printed model provides an advanced realistic environment for training and simulation of a wide range of SBS procedures.

Management strategy for bilateral complex vertebral artery aneurysms.

Bilateral complex vertebral artery aneurysms (BCoVAAns) have no established strategy of management. We retrospectively reviewed five consecutive patients with unruptured BCoVAAns between January 2006 and December 2012. Considering surgical risks of lower cranial nerve (LCN) injuries and eventual growth of an opposite side lesion after unilateral vertebral artery (VA) occlusion, we proposed a strategy of combined open and interventional treatment using revascularization. We applied the following several specific techniques: (1) proximal clipping and occipital artery-posterior inferior cerebellar artery (OA-PICA) and/or superficial temporary artery (STA)-superior cerebellar artery (SCA) bypasses; (2) Distal blood pressure, motor evoked potentials (MEPs), and somatosensory evoked potentials (SEPs) monitoring after parent artery temporary occlusion for safe permanent occlusion of the proximal portions of VA and PICA; (3) V3 to V4 bypass using radial artery (RA) graft with proximal clipping or trapping, two of them combined with OA-PICA bypass; (4) VA fenestration as an opportunity to preserve the flow of the parent artery. Two patients were treated bilaterally and 3 unilaterally, with modified Rankin scale assessed at 39 months postoperatively in average 0 in 2, 1 in 2, and 2 in 1, respectively, and the untreated opposite side lesions without regrowth or bleeding. Two patients with patent V3-RA-V4 bypass complained of dysphagia due to LCN palsies. One of them however suffered a cerebellar infarction due to occlusion of the OA-PICA bypass. When BCoVAAns require surgical treatment, revascularization or preservation of the VA should be considered at the first operation. By doing so, the opposite aneurysm can be effectively occluded by coil embolization, even with VA sacrifice if required.

Use of external lumbar cerebrospinal fluid drainage and lumboperitoneal shunts with Strata NSC valves in idiopathic normal pressure hydrocephalus: a single-center experience.

OBJECTIVE: In Japan, idiopathic normal pressure hydrocephalus (iNPH) currently is treated mainly with lumboperitoneal (LP) shunts. Our aim was to evaluate whether LP shunting via the use of Medtronic Strata NSC programmable valves was as effective as ventriculoperitoneal shunting in the treatment of patients with iNPH from the perspectives of safety and symptomatic improvement rate. METHODS: The clinical records of 51 iNPH patients (mean age, 75 years; males, 29), who underwent placement of Medtronic Strata NSC LP shunt systems were reviewed retrospectively as a cohort. LP shunting was evaluated with the modified Rankin Scale, the Japan Normal-Pressure Hydrocephalus Grading Scale, the Mini-Mental State Examination, the Frontal Assessment Battery, and the Trail-Making Test A as outcome measures. RESULTS: Modified Rankin Scale scores improved from 3.2 to 2.2 (P < 0.01), indicating a 64% response rate 12 months after treatment. Total Japan Normal-Pressure Hydrocephalus Grading Scale scores decreased from 6.5 to 4.0 (P < 0.01), indicating a response rate of 81%. Mini-Mental State Examination scores improved from 22.2 to 25.4 (P < 0.01), Frontal Assessment Battery scores improved from 11.7 to 13.4 (P < 0.05), and Trail-Making Test A scores improved from 122.3 to 112.7 (P = 0.60). During the 12-month follow-up period, complications requiring surgery were observed in 6 cases (11.8%). CONCLUSION: LP shunts showed effectiveness rates that were similar to those of ventriculoperitoneal shunts. Despite the relatively high complication rate, LP shunts can be recommended for the treatment of patients with iNPH because of their minimal invasiveness and lack of lethal complications.

A new support system using a mobile device (smartphone) for diagnostic image display and treatment of stroke.

BACKGROUND AND PURPOSE: With the increasing demand for rapid diagnosis and treatment of stroke, the telemedicine role of coordinating timely the efforts of the stroke team became important. We developed a system for rapidly exchanging diagnostic images and clinical and management information. METHODS: A system was created on the basis of communicating patient data and images between hospital systems and participating staff members in and out of the hospital through their standard, currently used handheld communication devices. The system is able to transfer clinical data, CT, MR, angiographic, intraoperative images, and expert opinion in real time. RESULTS: A pilot application of the system in our hospital showed successful information transfer, allowing medical staff to discuss patients' diagnosis and management using a Twitter system. CONCLUSIONS: The system (i-Stroke) may become a useful tool for acute patient management in the field of neurology and neurosurgery.

Leucine-rich α-2-glycoprotein is a marker for idiopathic normal pressure hydrocephalus.

OBJECTIVE: Cerebrospinal fluid (CSF) shunting can improve symptoms of elderly patients' idiopathic normal pressure hydrocephalus (iNPH). However, adjunctive means for confirming the diagnosis remain unavailable. We have previously reported the specific increase of leucine-rich alpha-2-glycoprotein (LRG) in iNPH CSF, and the present study investigates its potential clinical applications. METHODS: We performed CSF tap test (TT) on 90 patients (mean age 73.4 years) and shunting in 52 patients (mean age 73.5 years), evaluating symptom improvement and higher cerebral functions-mini-mental state examination (MMSE) and Frontal Assessment Battery (FAB) before and 12 months after shunting. LRG and tau protein concentrations in TT CSF were simultaneously measured using enzyme-linked immunosorbent assay. We then compared the predictive value of these concentrations with TT results regarding successful shunting outcomes. RESULTS: Positive combinations of TT and LRG concentrations of 67 ng/ml or higher, gave 81.6% sensitivity and 78.6% specificity. Therefore we used LRG (67 ng/ml) and tau (200 pg/ml) cut-off values, dividing patients into four groups. In group A (LRG ≥ 67 ng/ml and tau < 200 pg/ml) 31 of 34 patients (91.2%) had a positive TT and all operated 22 patients were shunt responders. Dementia MMSE and FAB scores in them increased from a baseline of 22.05(SE ± 0.96) to 25.65 (±0.85) and 11.38 (±0.68) to 13.08 (±0.57) respectively. In group B, (LRG ≥ 67 ng/ml and tau ≥ 200 pg/ml), the mean MMSE score increased from 17.62 (±2.03) to 21.62 (±1.96), and the FAB decreased slightly from 9.25 (±1.15) to 10.5 (±1.59), without improvement beyond the range of dementia. In group C, (LRG < 67 ng/ml, tau < 200 pg/ml), the mean MMSE score improved from 22.06 (±1.25) to 24.29 (±1.23) and the FAB score improved slightly from 12.0 (±0.72) to 12.87 (±0.72). Finally, in group D, (LRG < 67 ng/ml, tau ≥ 200 pg/ml), there was almost no improvement in MMSE score CONCLUSIONS: A combination of positive TT and biomarkers quantification such as LRG and tau protein, can reliably predict shunting outcome in iNPH patients.

Role of aneurysm projection in "A2" fork orientation for determining the side of surgical approach.

PURPOSE: To determine factors that help decide the side of approach for anterior communicating artery (AComA) aneurysms, based on a prospective study. METHODS: Between January 2004 and January 2006, 93 cases with AComA aneurysms were treated through pterional approach. They were classified as Type I, II (IIa, IIb), III and IV, based on the various projections and size of aneurysm. The principle for the choice of operative side was designed based on the type of aneurysm and the A2 fork orientation (the interrelations between the plane of bilateral A2, AComA, and mid-saggital plane). RESULTS: There were 55 aneurysms of Type I, 10 of Type IIa, 14 of Type IIb, 12 of Type III, and 2 of Type IV. In Types I and IIa, the side posteriorly placed to A2 was chosen for the approach. In Type IIb, the side of the dominant A1 was selected. In Type III, the side anteriorly placed to A2 was chosen. Type IV aneurysms were difficult to handle even if approached from the dominant A1. There were 11 cases treated from the side of non-dominant A1. The overall outcome in the treatment of AComA aneurysms were considered excellent in 90.8% of cases according to the Glasgow Outcome Scale, with complete occlusion of aneurysms and complete patency of parent or perforating arteries. CONCLUSIONS: Applying three-dimensional computed tomography and magnetic resonance angiography, we classified AComA aneurysms as four types and undertook surgical clipping from the chosen side of approach, according to the type of aneurysm and the A2 fork orientation. The selective side of approach on the basis of individual decision-making has led to favourable outcomes.

Dorsal column stimulation in persistent vegetative state.

Objectives. The problem of treating patients in a vegetative state remains grossly unresolved, and spinal cord stimulation (SCS) had seemed promising in some studies, suggesting, to us, further study. Materials and Methods. A prospective uncontrolled and nonrandomized observational study for 20 consecutive years (1986-2005) was performed on the effect of SCS in 214 patients in persistent vegetative state (PVS) that resulted from global anoxia and/or, stroke and/or head injury. After confirming the condition of PVS, a spinal cord stimulator, at the C2-C4 level, was implanted, stimulating according to a protocol of 15-min on/15-min off during daytime only. The results were evaluated using an efficacy scale designed by us for our study, detecting signs of awareness of self and surrounding. Results. Excellent and positive results were obtained in 109 of 201 patients (54%), but better in those patients below the age of 35, those of PVS of traumatic origin and those patients with regional cerebral blood flow over 20 mL/100 g/min. Conclusions. These findings, though inconclusive of actual benefit of SCS for PVS, indicate to us that further evidence-based, randomized controlled trials are needed to confirm efficacy of the treatment and define those who are going to benefit from this treatment method.

Usefulness of a simplified management scheme for paraclinoid aneurysms based on a modified classification.

BACKGROUND: Our objective was to set up a management-oriented classification for paraclinoid aneurysms, and then design and apply a simplified management scheme according to each group defined by this classification. METHODS: Paraclinoid aneurysms were classified as group I (supraophthalmic artery), group II (ophthalmic artery) and group III (infraophthalmic artery) aneurysms intradurally. Between January 2005 and December 2006, 86 cases with 89 paraclinoid aneurysms were treated. There were 35 (40.2%) aneurysms in group I (20 in group Ia, 15 in group Ib), 32 (36.8%) in group II and 20 (23%) in group III. RESULTS: In group I aneurysms, 20 (57.1%) were treated by clipping or/and wrapping, while 15 (42.9%) were managed by coiling. In group II aneurysms, 20 (62.5%) were treated by clipping and 12 (37.5%) by coiling. The contralateral approach was performed for 4 (6%) aneurysms in groups I and II. All 20 group III aneurysms were treated by coiling. The overall rate of permanent complications was 4.6%. The rate of complete occlusion was 92.5% in surgical cases and 55.6% in endovascular ones. The overall outcomes in the treatment of paraclinoid aneurysms were excellent (GOS = 5, 95.4%). CONCLUSION: Based on our modified classification of paraclinoid aneurysms, a simplified management scheme was designed and applied. For group I (supraophthalmic artery) and group II (ophthalmic artery) aneurysms, surgical clipping or/and wrapping should be the first choice of treatment, while for group III (infraophthalmic artery) aneurysms, endovascular coiling should be the best modality. Additionally, individualizing the treatment planning might contribute to better results.

Management of complex, surgically intractable intracranial aneurysms: the option for intentional reconstruction of aneurysm neck followed by endovascular coiling.

BACKGROUND: A limited series of patients with aneurysm were reviewed retrospectively to analyze strategies for integrating microsurgical and endovascular techniques in the management of complex, surgically intractable aneurysms. METHODS: Four patients were managed in Fujita Health University with a multimodality approach: intentional reconstruction of the aneurysm neck followed by endovascular coiling. RESULTS: A total of 5 aneurysms were treated, of which 3 were large or giant in size, and 3 were fusiform or multilobulated. Complete angiographic obliteration was confirmed in 4 aneurysms (80%). All patients had a good outcome (Glasgow Outcome Scale score 5; mean follow-up, 64 months). CONCLUSION: As for complex, surgically intractable aneurysms, the intentional reconstruction of the aneurysm neck followed by endovascular coiling should be considered more often.