Dome Projection Research Articles

Impact of Aneurysmal Neck Position in Endovascular Therapy for Anterior Communicating Artery Aneurysms.

Anterior communicating artery (ACoA) aneurysms have a complex architecture and many variations, making endovascular therapy more difficult in some cases. The aim of this study was to investigate whether the neck position of an aneurysm was identifiable for determining the immediate angiographic success and procedural complications in the coiling of the ACoA aneurysms. We conducted a retrospective case review of 40 patients with ACoA aneurysms treated by endovascular therapy from 2008 to 2015. The mean age was 66.8 years. Thirty-five aneurysms were ruptured; five were unruptured. For the analysis, the patients were divided into two groups according to the neck position of aneurysms: the true ACoA group, 9 patients with the neck located on the ACoA itself; and the other ACoA group, 31 patients with the neck at the junction of the A1 and A2 portions of an anterior cerebral artery. Morphological characteristics (dome size, dome direction, rate of wide neck, and angulation of aneurysms in relation to the parent artery) were analyzed along with immediate angiographic results, volume embolization ratio (VER), and procedural complications. Small aneurysms with superior dome projection and acute angulation of the aneurysm direction occurred more often in the true ACoA group. The rates of complete obliteration, VER, and procedural complications were 33.3%, 32.3%, and 22.2% in the true ACoA group and 54.8%, 36.3%, and 6.5% in the other ACoA group, respectively. True ACoA aneurysms could present an anatomical difficulty in endovascular coiling. Aneurysmal neck position should be accurately assessed to achieve successful embolization of the ACoA aneurysms.

Can child-pedestrians’ hazard perception skills be enhanced?

ObjectiveTraffic collisions yield a substantial rate of morbidity and injury among child-pedestrians. We explored the formation of an innovative hazard perception training intervention – Child-pedestrians Anticipate and Act Hazard Perception Training (CA2HPT). Training was based upon enhancing participants’ ability to anticipate potential hazards by exposing them to an array of traffic scenes viewed from different angles. MethodTwenty-four 7–9-year-olds have participated. Trainees underwent a 40-min intervention of observing typical residential traffic scenarios in a simulated dome projection environment while engaging in a hazard detection task. Trainees were encouraged to note differences between the scenarios presented to them from separate angles (a pedestrian's point-of-view and a higher perspective angle). Next, trainees and control group members were required to perform crossing decision tasks. ResultsTrainees were found to be more aware of potential hazards related to restricted field of view relative to control. ConclusionsChild pedestrians are responsive to training and actively detecting materialized hazards may enrich child-pedestrians’ ability to cross roads.

Treatment of Ruptured Anterior Communicating Artery Aneurysms: Equipoise in the Endovascular Era?

Ruptured anterior communicating artery (ACoA) aneurysms are heterogeneous intracranial aneurysms whose diverse morphological features influence treatment modality. To compare clinical outcomes and complications of all ruptured ACoA aneurysms treated by clipping or coiling in a modern institutional trial. All patients with ruptured ACoA aneurysms in the Barrow Ruptured Aneurysm Trial were included. Clinical follow-up at 1 and 3 years was analyzed; charts were reviewed for patient demographics, aneurysm characteristics, and in-hospital complications. This cohort included 130 patients (mean age, 52.5 years). Mean aneurysm size was 5.8 mm. Most aneurysm domes projected anteriorly (n = 52). After randomization and crossover, 91 ACoA aneurysms (70%) were clipped and 39 (30%) were coiled. Twenty-two patients (16.9%) initially randomized to coiling crossed over to clipping after evaluation. No patients crossed over from clipping to coiling. Characteristics precluding aneurysms from coiling included unfavorable dome-to-neck ratio, lesions difficult to access by catheter, and branch vessel involvement. Aneurysm size and dome projection were not significantly associated with treatment group, clinical outcome, or retreatment. No significant difference existed in clinical outcome (modified Rankin Scale scores) between groups at discharge or at 1-year or 3-year follow-up using as-treated and intention-to-treat analyses. Retreatment was performed in 3 clipped patients (2.3%) and 3 coiled patients (2.3%). Ruptured ACoA aneurysms, regardless of size and projection, were safely treated by both treatment modalities in a large-scale randomized clinical trial. Clinical outcomes and stroke rates did not differ significantly in as-treated or intention-to-treat analyses.

Localization in the Interpeduncular Cistern as Risk Factors for the Thalamoperforators' Ischemia, Poor Outcome, and Oculomotor Nerve Palsy in Patients with Complex Unruptured Basilar Apex Aneurysm Treated with Neck Clipping

We aimed to evaluate the relationship between aneurysm morphology, thalamoperforators' ischemia, outcome, and oculomotor nerve palsy (ONP) that continued during the follow-up period in 23 patients with complex unruptured basilar apex aneurysms (BAAs) treated with clipping. Aneurysm morphology included the size, distance of neck from the posterior clinoid process, dome projection, and localization in the interpeduncular cistern (LIC). BAAs with neck >4 mm, posterior projection, retro/subsellar, and dome-to-neck ratios <1.2 were considered as complex. The poor outcome was defined as modified Rankin Scale (mRS) 2-6 at the 12 months' follow-up examination. All patients were treated by anterior temporal approach. Size (P < 0.0001) and LIC (P < 0.0001) were related to thalamoperforators' ischemia (n = 3, 13%). Size (P = 0.0010), dividing-posterior communicating artery (P = 0.0050), thalamoperforator's ischemia (P = 0.034), and LIC (P < 0.0001) were related to poor outcome (mRS 2: n = 3, 13%). The mean follow-up period was 368 ± 52 days. No patients developed a bleed and showed evidence of any residual or recurrent aneurysm during follow-up. Postoperative ONP occurred in 15 patients (65%) and all were partial. During follow-up, full recovery of the ONP was seen in 13 patients (57%), and it continued in 2 (8.7%). Size (P = 0.010) and posterior projection (P = 0.043) and LIC (P = 0.0050) were related to continued ONP. The present study suggested that unruptured BAA patients with LIC should be meticulously treated in case of performing clipping because it was related to thalamoperforators' ischemia, poor outcome, and continued ONP.

Anterior Communicating Artery Aneurysm Surgery

Head positioning and the degree of rotation for anterior communicating artery aneurysm surgery is controversial. With this anatomic study, we aimed to give a broad description of head positioning for various aneurysm dome projections. In addition, with the use of a corrosion-cast technique, a three-dimensional arterial tree was demonstrated, an anterior communicating artery region aneurysm model was prepared, and pictures were taken at various angles. According to our observations, 30-degree head rotation was found to be the most suitable position for the anterior and superior projected aneurysms. For posterior projection, aneurysm neck was best viewed with 15-degree head rotation. Aneurysms projecting inferiorly necessitated the greatest rotation at 45 degrees. Each aneurysm dome projection of the anterior communicating artery aneurysm should be individually considered, and the head position should be adjusted accordingly. The use of appropriate head positions during surgery will prevent the development of postoperative ischemic complications and will increase the success of surgery by preventing unnecessary tissue manipulation.

The influence of SiO2 doping on the microstructure and photochromic behavior of phosphomolybdic acid/polyvinyl pyrrolidone hybrid films

New hybrid films were synthesized by SiO2 doping into phosphomolybdic acid (PMoA)/polyvinyl pyrrolidone (PVPd) composite system, and the effect of SiO2 doping on microstructure and photochromic properties was studied via atomic force microscope (AFM), Fourier transform infrared spectroscopy (FT-IR), ultraviolet–visible spectra (UV–vis) and X-ray photoelectron spectroscopy (XPS). The hybrid film surface with dome projection changed rough from smooth after SiO2 doping. The vibrational spectra of FT-IR verified that component of the heteropolyacids and the polymer did not changed, the vibration bands were expanded and had shifted by a few cm−1, and changed interaction between the acid and the polymer after SiO2 doping. The hybrid film exhibited a good photochromic property, which changed from colorless to blue under UV irradiation. The color change intensity of SiO2/PMoA/PVPd film was 1.48 times stronger than that of PMoA/PVPd under the same condition. XPS results indicated that the amount of PMoA in photo-reductive reaction was increased after SiO2 doping.

A Novel Craniotomy Simulator Provides a Validated Method to Enhance Education in the Management of Traumatic Brain Injury

Abstract BACKGROUND: The middle cerebral artery (MCA) is the most frequent location for unruptured intracranial aneurysms. Controversy remains as to which unruptured MCA aneurysms should be treated prophylactically. OBJECTIVE: To identify independent topographical and morphological variables that could predict increased rupture risk of MCA aneurysms. METHODS: A retrospective analysis of computed tomography angiography data of 1009 consecutive patients with 1309 MCA aneurysms, referred between 2000 and 2009 to Helsinki University Hospital, was carried out. Morphological and topographical parameters examined for MCA aneurysms comprised aneurysm wall regularity, size, neck width, aspect ratio, bottleneck factor, height-width ratio, location along the MCA, side, distance from the internal carotid artery bifurcation, and dome projection in axial and coronal computed tomography angiography views. Univariate and multivariate logistic regression analyses were performed to determine independent risk factors for rupture. RESULTS: Of the 1309 MCA aneurysms, 69% were unruptured and 31% were ruptured. Most unruptured MCA aneurysms were smaller than 7 mm (78%), with a smooth wall (80%) and a height-width ratio of 1 (47%) and were located at the main bifurcation (57%). Ruptured MCA aneurysms, mostly 7 to 14 mm in size (55%), had an irregular wall (78%) and a height-width ratio greater than 1 (72%) and were located at the main bifurcation (77%). Thirty-eight percent of MCA bifurcation aneurysms, 74% of large aneurysms, 64% of aneurysms with an irregular wall, and 49% of aneurysms with a height-width ratio greater than 1 were ruptured. CONCLUSION: Location at the main MCA bifurcation, wall irregularity, and less spherical geometry were independently associated with rupture of MCA aneurysms with a correlation with aneurysm size.

Morphological and clinical risk factors for the rupture of anterior communicating artery aneurysms

Patients with ruptured anterior communicating artery (ACoA) aneurysms have historically been observed to have poor neuropsychological outcomes, and ACoA aneurysms have accounted for a higher proportion of ruptured than unruptured aneurysms. Authors of this study aimed to investigate the morphological and clinical characteristics predisposing to ACoA aneurysm rupture. Data from 140 consecutive patients with ACoA aneurysms managed at the authors' facility between July 2003 and November 2011 were retrospectively reviewed. Patients with (78) and without (62) aneurysm rupture were divided into groups, and morphological and clinical characteristics were compared. Morphological characteristics were evaluated based on 3D CT angiography and included aneurysm location, dominance of the A1 portion of the anterior cerebral artery, direction of the aneurysm dome around the ACoA, aneurysm bleb(s), size of the aneurysm and its neck, aneurysm-parent artery angle, and existence of other intracranial unruptured aneurysms. Patients with ruptured ACoA aneurysms were significantly younger (a higher proportion were younger than 60 years of age) than those with unruptured lesions, and a significantly smaller proportion had hypercholesterolemia. A significantly larger proportion of patients with ruptured aneurysms showed an anterior direction of the aneurysm dome around the ACoA, had a bleb(s), and/or had an aneurysm size ≥ 5 mm. Multivariate logistic regression analysis showed that an anterior direction of the aneurysm dome around the ACoA (OR 6.0, p = 0.0012), the presence of a bleb(s) (OR 22, p < 0.0001), and an aneurysm size ≥ 5 mm (OR 3.16, p = 0.035) were significantly associated with ACoA aneurysm rupture. Findings in the present study demonstrated that the anterior projection of an ACoA aneurysm may be related to rupturing. The authors would perhaps recommend treatment to patients with unruptured ACoA aneurysms that have an anterior dome projection, a bleb(s), and a size ≥ 5 mm.

未破裂前交通動脈瘤へのより安全な手術アプローチ―瘤の突出方向による手術法の選択―

There are 2 kinds of surgical approaches to unruptured anterior communicating artery aneurysm (Acom an): the pterional and interhemispheric approach. Currently, the thoice of approach depends on the surgeon’s preference and experience. In our study, we compared the interrelationship between appropriate surgical approach and dome projection among the following 3 groups: anterior/inferior, superior, and posterior projections. The results showed only aneurysms with anterior/inferior dome projection were suitable for the pterional approach. However, the interhemispheric approach was preferable for aneurysms with all other projections except for anterior/inferior projection. Surgeons should be familiar with both approaches so they we can select according to dome projection of Acom an.

Discussion

Background:Nasoalveolar molding was developed to improve dentoalveolar, septal, and lower lateral cartilage position before cleft lip repair. Previous studies have documented the long-term maintenance of columella length and nasal dome form and projection. The purpose of the present study was to det

Nasoalveolar Molding Improves Long-Term Nasal Symmetry in Complete Unilateral Cleft Lip–Cleft Palate Patients

Nasoalveolar molding was developed to improve dentoalveolar, septal, and lower lateral cartilage position before cleft lip repair. Previous studies have documented the long-term maintenance of columella length and nasal dome form and projection. The purpose of the present study was to determine the effect of presurgical nasoalveolar molding on long-term unilateral complete cleft nasal symmetry. A retrospective review of 25 consecutively presenting nonsyndromic complete unilateral cleft lip-cleft palate patients was conducted. Fifteen patients were treated with presurgical nasoalveolar molding for 3 months before surgical correction, and 10 patients were treated by surgical correction alone. The average age at the time of follow-up was 9 years. Four nasal anthropometric distances and two angular relationships were measured to assess nasal symmetry. All six measurements demonstrated a greater degree of nasal symmetry in nasoalveolar molding patients compared with the patients treated with surgery alone. Five symmetry measurements were significantly more symmetric in the nasoalveolar molding patients and one measurement demonstrated a nonsignificant but greater degree of symmetry compared with the patients treated with surgery alone. The data demonstrate that the lower lateral and septal cartilages are more symmetric in the nasoalveolar molding patients compared with the surgery-alone patients. Furthermore, the improved symmetry observed in nasoalveolar molding-treated noses during the time of the primary surgery is maintained at 9 years of age.

Image-guided microneurosurgical management of vascular lesions using navigated computed tomography angiography. an advanced IGS technology application

Image-guided neurosurgery has become a standard practice in the last few years, with more than 2000 surgical navigation stations installed worldwide. In the same time several reports have also demonstrated the efficacy and accuracy of computed tomography angiography (CTA) in assessing cerebral vascular pathologies. Therefore, the CTA data have recently been implemented into the different navigation systems available on the market, making this new technique widely applied. The objective of this paper is to discuss and evaluate the clinical usefulness of navigated CTA in planning and performing surgery of neurovascular lesions. Raw images acquired from an helical CTA are automatically post-processed on an independent workstation by using a three-dimensional (3D) volume-rendering images engine and/or using thresholding and drawing tools. The data obtained provide useful information in the preoperative stage by reconstructing the vascular tree with regard to lesion volume, aneurysm neck, dome projection, perforating vessels and their relationship with the lesion and the surrounding anatomy. Furthermore, it can help in the identification of an arteriovenous malformation (AVM) nidus and recognition of its feeding and draining vessels. This fascinating technique can give some invaluable advantages on the management of cerebral vascular lesions and provides excellent information not always available on traditional digital subtraction angiography investigation. It has also proved to be very accurate, particularly regarding the correlation between the 3D volume-rendered CT angiography and the intraoperative findings.

Primary Correction of Unilateral Cleft Lip Nasal Deformity in Asian Patients: Anthropometric Evaluation

Previously it was thought that primary correction of nasal deformity in cleft lip patients would cause developmental impairment of the nose. It is now widely accepted that simultaneous correction of the cleft lip nasal deformity has no adverse effect on nasal growth. Thus, the authors tried to evaluate the results of primary correction of cleft lip in Asian patients. Of 412 cases of cleft lip, 195 cases were corrected by means of the conventional method from June of 1992 to June of 1997, and 217 cases were corrected by simultaneous rhinoplasty from July of 1997 to October of 2001. The average patient age was 3 months. Photographs and anthropometric evaluation were used to evaluate the results. Nasal tip projection, columellar length, and nasal width were measured in 60 randomized normal children, 30 randomized children treated with the conventional method, and 30 randomized children with primary nasal repair. Data were analyzed using t tests, and the level of significance was 5 percent (p < 0.05). In cases of simultaneous repair, nasal tip projection and columellar length were increased 24.8 percent and 28.8 percent, respectively. Nasal width was increased 12.3 percent in the cases of simultaneous repair and 12.6 percent in the cases without primary rhinoplasty. Simultaneous repair of cleft lip and nasal deformity in Asian patients showed that more symmetry of nostril and nasal dome projection and better correction of buckling and alar flaring were achieved. More balanced growth and development of the alar complex was achieved, and no interference with nasal growth was encountered.

Primary correction of the unilateral cleft nasal deformity.

An 18-year experience with the management of the unilateral cleft nasal deformity in 1200 patients is presented. A primary cleft nasal correction was performed at the time of lip repair in infancy; a secondary rhinoplasty was done in adolescence after nasal growth was complete. The technical details of the authors' primary cleft nasal correction are described. Exposure was obtained through the incisions of the rotation-advancement design. The cartilaginous framework was widely undermined from the skin envelope. The nasal lining was released from the piriform aperture, and a new maxillary platform was created on the cleft side by rotating a "muscular roll" underneath the cleft nasal ala. The alar web was then managed by using a mattress suture running from the web cartilage to the facial musculature. In 60 percent of cases, these maneuvers were sufficient to produce symmetrical dome projection and nostril symmetry. In the other 40 percent, characterized by more severe hypoplasia of the cleft lower lateral cartilage, an inverted U infracartilaginous incision and an alar dome supporting suture (Tajima) to the contralateral upper cartilage were used. Residual dorsal hooding of the lower lateral cartilage was most effectively managed with this suture. This primary approach to the cleft nasal deformity permits more balanced growth and development of the ala and domal complex. Some of the psychological trauma of the early school years may be avoided. Also, because of the early repositioning of the cleft nasal cartilages, the deformity addressed at the time of the adult rhinoplasty is less severe and more amenable to an optimal final result.

Transient cardio-respiratory responses to visually induced tilt illusions

Although the orthostatic cardio-respiratory response is primarily mediated by the baroreflex, studies have shown that vestibular cues also contribute in both humans and animals. We have demonstrated a visually mediated response to illusory tilt in some human subjects. Blood pressure, heart and respiration rate, and lung volume were monitored in 16 supine human subjects during two types of visual stimulation, and compared with responses to real passive whole body tilt from supine to head 80° upright. Visual tilt stimuli consisted of either a static scene from an overhead mirror or constant velocity scene motion along different body axes generated by an ultra-wide dome projection system. Visual vertical cues were initially aligned with the longitudinal body axis. Subjective tilt and self-motion were reported verbally. Although significant changes in cardio-respiratory parameters to illusory tilts could not be demonstrated for the entire group, several subjects showed significant transient decreases in mean blood pressure resembling their initial response to passive head-up tilt. Changes in pulse pressure and a slight elevation in heart rate were noted. These transient responses are consistent with the hypothesis that visual-vestibular input contributes to the initial cardiovascular adjustment to a change in posture in humans. On average the static scene elicited perceived tilt without rotation. Dome scene pitch and yaw elicited perceived tilt and rotation, and dome roll motion elicited perceived rotation without tilt. A significant correlation between the magnitude of physiological and subjective reports could not be demonstrated.

39.3: Recent Advances In Dome Display Systems

AbstractPolysilicon LCD projection technology has advanced to the point that it is now worthy of consideration for the demanding requirements of fast‐jet flight simulation visual displays. Other technologies show promise of introducing more options and all of these will offer benefits of high stability, low cost, high brightness and on‐going improvement as much larger markets drive demand. This paper explores how such opportunities are now being exploited in the development of fully immersive dome projection systems.

Aesthetic considerations related to repair of the bilateral cleft lip nasal deformity

Abstract A study of the changing configuration of the nose with age shows that the columella naturally takes a greater share of nose projection with increasing age. In the infant and small child, when most repairs are done, nose projection is due more to the alar dome component than to the columella. Over-lengthening the columella at the expense of alar dome projection results in an unaesthetic nose at maturity. The nasal correction should be towards a normal proportion for age and attention must be paid to alar dome configuration. Where the inferior view shows a tent tip skyline, lateral crus advancement is required and can be achieved in asynchronous repairs by Pigott alar leapfrog at primary repair or by Potter V-Y advancement at the time of forked flap columella lengthening. The profile view of the nose and lip shows that the lip drops from a point about two-thirds of the way from nostril apex to alar base. A key stitch advancing the alar bases at the time of columella lengthening allows the philtral area to bow forwards as a prow so that it comes to lie in a normal relationship with the columella in the profile view.

Aesthetic considerations related to repair of the bilateral cleft lip nasal deformity

A study of the changing configuration of the nose tip with age shows that the columella naturally takes a greater share of nose tip projection with increasing age. In the infant and small child, when most repairs are done, nose tip projection is due more to the alar dome component than to the columella. Over-lengthening the columella at the expense of alar dome projection results in an unaesthetic nose at maturity. The nasal correction should be towards a normal proportion for age and attention must be paid to alar dome configuration. Where the inferior view shows a “tent tip” skyline, lateral crus advancement is required and can be achieved in asynchronous repairs by Pigott alar leapfrog at primary repair or by Potter V-Y advancement at the time of forked flap columella lengthening. The profile view of the nose and lip shows that the lip “drops” from a point about two-thirds of the way from nostril apex to alar base. A key stitch advancing the alar bases at the time of columella lengthening allows the philtral area to bow forwards as a prow so that it comes to lie in a normal relationship with the columella in the profile view.