A new hand-held holder optimizes the parameters of the laser-induced choroidal neovascularization model in mice.

BACKGROUND: The laser-induced choroidal neovascularization (CNV) mouse model, as the most classic animal model of age-related macular degeneration (AMD), has been widely used. We designed a hand-held mouse holder to optimize mouse fixation in the laser-induced CNV modelling process, which was inconvenient until now. This study aimed to evaluate the effectiveness of our in-house hand-held mouse holder design in the laser-induced CNV mouse modelling process. METHODS: Six ophthalmic residents were invited to perform laser-induced CNV mouse modelling by hand or using the holder. We compared the learning time of residents and their physical and mental fatigue with the two methods. In addition, we compared the parameters of CNV modelling with two methods by a skilled operator, including the time of photocoagulation, induction rate and uniformity of CNV lesions. RESULTS: In the learning phase, the average learning time to master the modelling method was significantly shortened by utilizing the holder. The fatigue in the operation process was quantified to a level from 0 to 4, and the physical fatigue by using holder (0.8 ± 0.3) was lower than by hand (2.6 ± 0.4), and the mental fatigue was relieved from 2.3 ± 0.5 to 0.4 ± 0.3. On the other hand, the skilled operator can significantly shorten the time of laser photocoagulation from 146.7 ± 36.0 s to 63.6 + 5.7 s and improve the success rate of modelling from 50.0% ± 8.3%-87.5% ± 6.7% by using a holder compared to hand. In addition, the standard error of the mean (SEM) of the distance between the CNV lesion and the optic nerve (ON) and the distance between each lesion was reduced. CONCLUSION: This hand-held mouse holder could optimize the setting and conditions of laser-induced CNV mouse modelling by improving the learning curve, reducing fatigue, shortening the time for photocoagulation, improving the success rate and consistency of laser-induced lesions.

A Rat Model of Frozen Shoulder Demonstrating the Effect of Transcatheter Arterial Embolization on Angiography, Histopathology, and Physical Activity.

PURPOSE: To assess the angiographic findings and the effects of transcatheter arterial embolization on physical activity and histopathology using a frozen shoulder rat model. MATERIALS AND METHODS: First, the angiographic and histopathologic findings of rats in which the shoulder was immobilized with molding plaster for 6 weeks (n = 4) were compared to control rats with normal non-immobilized shoulders (n = 4). Next, a total of 16 frozen shoulder rats were divided into 2 groups. In the transcatheter arterial embolization group (n = 8), imipenem/cilastatin was injected into the left thoracoacromial artery. The changes of physical activity before and after procedures were evaluated and compared with a saline-injected control group (n = 8). Histopathologic findings were also compared between the 2 groups. RESULTS: Angiography revealed abnormal shoulder staining in all of the rats with a frozen shoulder. On histopathology, the numbers of microvessels and mononuclear inflammatory cells in the synovial membrane of the joint capsule were significantly higher compared with the control rats (both P = .03). In the transcatheter arterial embolization group, the running distance and speed were improved (P = .03 and P = .01, respectively), whereas there were no significant differences in the control group. The number of microvessels and mononuclear inflammatory cells in the transcatheter arterial embolization group were significantly lower than the control group (P = .002 and P = .001, respectively). CONCLUSIONS: The rat frozen shoulder model revealed the development of neovascularization. Transcatheter arterial embolization decreased the number of blood vessels and inflammatory changes in the frozen shoulder and increased the moving distance and speed of the rats.

Forensic evaluation of alleged wrist restraint/handcuff injuries in survivors of torture utilizing the Istanbul Protocol.

Despite being a common form of abuse, there is a paucity of literature describing shackling and wrist restraint injuries among survivors of torture. Forensic evaluation of alleged wrist restraint/handcuff injuries in survivors of torture presents challenges to the evaluator, especially if the injuries are remote and do not leave lasting marks nor neurologic deficits. Thorough history-taking and physical examination are critical to effective forensic documentation. Guidance is provided in The Manual on Effective Investigation and Documentation of Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment (Istanbul Protocol), the gold standard for the medicolegal documentation of torture. This guidance relies primarily on physical findings, with less direction provided on how to interpret historical evidence or when historical evidence provided by the patient can be interpreted as highly consistent with alleged injury in the absence of current physical findings. Through a case-based review, we present diagnostic strategies for the evaluation of alleged abuse involving wrist restraints/handcuffs, focusing on skin, neurologic, and osseous injuries. We highlight key findings from both the history and physical examination that will allow the evaluator to improve the accuracy of their expert medical opinion on the degree to which medical findings correlate with the patient's allegations of wrist restraint injuries.

Decline in Physical Restraint Use Following Implementation of Institutional Guidelines.

OBJECTIVE: To investigate the strategies implemented at our institution to reduce medical restraint use. BACKGROUND: Restraints have been utilized to prevent agitation, self-extubations, and falls, although they are often associated with negative repercussions for nurses and patients. METHODS: The restraint data at our institution were compared with the National Database of Nursing Quality Indicators (NDNQI) benchmark. We also described the measures taken to improve restraint documentation. RESULTS: The number of patients in medical restraints, medical restraint hours, medical restraints/patient-days, and deaths in restraints at our institution all significantly decreased (P < 0.00001). There were 27 self-extubations of restrained patients compared with 11 self-extubations of nonrestrained patients. The percentage of inpatients with restraints in critical care and step-down areas declined and remained below the NDNQI benchmark. CONCLUSIONS: This study reports the processes implemented to reduce restraint use through enhanced communication and increased documentation. Further exploration into factors that may attain a restraint-free environment is warranted.

Exploring head and neck cancer patients' experiences with radiation therapy immobilisation masks: A qualitative study.

OBJECTIVE: Head and neck cancer (HNC) patients commonly undergo radiation therapy requiring immobilisation by a mask. Some find the mask distressing, and this can disrupt treatment sessions. This study aimed to explore the patient experience of immobilisation masks in the Australian and New Zealand (ANZ) context, to guide possible intervention. METHODS: Semi-structured interviews were conducted with HNC patients who had completed radiation therapy, recruited via hospitals and social media. Interviews continued until data saturation; then, three further interviews were conducted for member-checking purposes. Qualitative methodology with thematic analysis was used to identify themes in the data. RESULTS: Twenty HNC survivors participated in interviews, and seven themes were identified: information received by participants, potential predictors of mask anxiety, participant reactions to the mask, trajectories of mask anxiety, supportive behaviour and communication of health professionals, coping with the mask, and thoughts and feelings about the mask. CONCLUSIONS: Participant experiences of the immobilisation mask were diverse. The findings fit with Lazarus and Folkman's (Stress, appraisal, and coping. New York, NY: Springer Pub. Co) transactional model of stress and coping, as participants appeared to make cognitive appraisals of the mask and their coping abilities throughout treatment, resulting in varied levels of mask-related distress. Complex intervention is recommended to reduce mask anxiety in HNC patients across ANZ.

Customized head molds reduce motion during resting state fMRI scans.

Head motion causes artifacts in functional magnetic resonance imaging (fMRI) scans, a problem especially relevant for task-free resting state paradigms and for developmental, aging, and clinical populations. In a cohort spanning 7-28 years old (mean age 15) we produced customized head-anatomy-specific Styrofoam molds for each subject that inserted into an MRI head coil. We scanned these subjects under two conditions: using our standard procedure of packing the head coil with foam padding about the head to reduce head motion, and using the customized molds to reduce head motion. In 12 of 13 subjects, the molds reduced head motion throughout the scan and reduced the fraction of a scan with substantial motion (i.e., volumes with motion notably above baseline levels of motion). Motion was reduced in all 6 head position estimates, especially in rotational, left-right, and superior-inferior directions. Motion was reduced throughout the full age range studied, including children, adolescents, and young adults. In terms of the fMRI data itself, quality indices improved with the head mold on, scrubbing analyses detected less distance-dependent artifact in scans with the head mold on, and distant-dependent artifact was less evident in both the entire scan and also during only low-motion volumes. Subjects found the molds comfortable. Head molds are thus effective tools for reducing head motion, and motion artifacts, during fMRI scans.

Complications of Halo Placement.

BACKGROUND: The halo vest is widely used throughout the world to manage craniovertebral and cervical instabilities. It can be used for postoperative immobilization or as an alternative to surgical fixation. METHOD: In this paper we present some cases of severe complications from our own practice and review the literature on halo complications. RESULTS: Like any therapeutic manoeuvre, halo placement may be followed by various complications. In the meantime, modern techniques of fixation offer safe and immediate stabilization. CONCLUSION: The halo vest remains a formidable method for cervical immobilization. However, it should not be used a priori instead of surgery.

BET 1: cervical spine immobilisation in the management of drowning victims.

A short cut review was carried out to establish whether patients presenting to the emergency department after a near drowning should have cervical spine immobilisation. A search of the literature found only three studies directly relevant to the question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. The clinical bottom line is that cervical spine injuries are rare in drowning and near drowning unless there is a history of diving or a fall or signs of trauma. Cervical spine immobilisation should be reserved for cases where there is a reasonable suspicion of a spinal injury.

A novel device for real-time measurement and manipulation of licking behavior in head-fixed mice.

The mouse has become an influential model system for investigating the mammalian nervous system. Technologies in mice enable recording and manipulation of neural circuits during tasks where they respond to sensory stimuli by licking for liquid rewards. Precise monitoring of licking during these tasks provides an accessible metric of sensory-motor processing, particularly when combined with simultaneous neural recordings. There are several challenges in designing and implementing lick detectors during head-fixed neurophysiological experiments in mice. First, mice are small, and licking behaviors are easily perturbed or biased by large sensors. Second, neural recordings during licking are highly sensitive to electrical contact artifacts. Third, submillisecond lick detection latencies are required to generate control signals that manipulate neural activity at appropriate time scales. Here we designed, characterized, and implemented a contactless dual-port device that precisely measures directional licking in head-fixed mice performing visual behavior. We first determined the optimal characteristics of our detector through design iteration and then quantified device performance under ideal conditions. We then tested performance during head-fixed mouse behavior with simultaneous neural recordings in vivo. We finally demonstrate our device's ability to detect directional licks and generate appropriate control signals in real time to rapidly suppress licking behavior via closed-loop inhibition of neural activity. Our dual-port detector is cost effective and easily replicable, and it should enable a wide variety of applications probing the neural circuit basis of sensory perception, motor action, and learning in normal and transgenic mouse models. NEW & NOTEWORTHY Mice readily learn tasks in which they respond to sensory cues by licking for liquid rewards; tasks that involve multiple licking responses allow study of neural circuits underlying decision making and sensory-motor integration. Here we design, characterize, and implement a novel dual-port lick detector that precisely measures directional licking in head-fixed mice performing visual behavior, enabling simultaneous neural recording and closed-loop manipulation of licking.

Comparison of the Memory Foam Pad Versus the Bean Bag with Shoulder Braces in Preventing Patient Displacement during Gynecologic Laparoscopic Surgery.

STUDY OBJECTIVE: To compare the amount of patient displacement when a memory foam pad is used versus a bean bag with shoulder braces. The secondary aim was to evaluate for postoperative extremity symptoms including pain, numbness, and weakness. DESIGN: A prospective randomized pilot study (Canadian Task Force classification I). SETTING: A single academic institution. PATIENTS: Women ≥18 years of age undergoing laparoscopic or robotic gynecologic surgery. INTERVENTIONS: Patients were randomized to be positioned on the memory foam pad (group A) or the bean bag with shoulder braces (group B) preoperatively. The patients' positions were measured before and after the procedure, and the displacement was recorded. Patients were followed postoperatively and questioned regarding upper extremity or lower extremity weakness, numbness, and pain. Demographic characteristics were collected using the electronic medical record. MEASUREMENTS AND MAIN RESULTS: Forty-three patients were included in the study (22 in group A and 21 in group B). The demographic and intraoperative characteristics of the patients were similar in both groups. The patients in group A moved a mean distance of 3.80 ± 3.32 cm, whereas those in group B moved a mean distance of 1.07 ± 1.93 cm (p = .002). A Pearson correlation coefficient did not yield a correlation between patient displacement and age, body mass index, length of surgery, or pathology weight. In group A, 2 patients had lower extremity numbness, and 1 patient had upper extremity numbness. In group B, 1 patient had upper extremity pain, and 1 patient had both upper and lower extremity numbness. These patients had complete resolution of their symptoms within the first 2 weeks postoperatively, with the exception of 1 patient in group A whose lower extremity numbness resolved 3 months postoperatively. CONCLUSION: Positioning patients on the bean bag with shoulder braces resulted in significantly less displacement during gynecologic laparoscopic surgery when compared with the memory foam pad. All postoperative extremity numbness, weakness, and pain were temporary and resolved completely in our cohort. A larger study would be necessary to determine the true incidence of peripheral nerve injuries because these are rare complications of laparoscopic surgeries.

Cervical spine immobilisation in the elderly: a literature review.

Developed populations are ageing rapidly and by 2040, approximately 1 in 4 adults will be over 65 years of age. This is resulting in higher incidence of traumatic injury in older patients. Cognitive and physical comorbidities in this group can pose significant challenges. Due to mechanisms of injury and pre-existing degenerative spinal disease, cervical spine fractures are particularly prevalent in elderly patients. These are associated with significant morbidity and mortality. In this literature review we examine current evidence surrounding the use of cervical spine immobilisation in elderly patients in the pre-hospital and emergency department setting and also as a treatment option for cervical spine fractures. We explore evidence surrounding the complications that can arise from cervical spine immobilisation, including the development of pressure sores, raised intracranial pressure, dysphagia, breathing difficulties, delirium, compliance issues, mobility and functional outcome.

Dynamic magnetic resonance imaging of carbogen challenge on awake rabbit brain at 1.5T.

BACKGROUND: Anesthesia may alter the cellular components contributing to the magnetic resonance imaging (MRI) signal intensities. Developing awake animal models to evaluate cerebral function has grown in importance. OBJECTIVE: To investigate a noninvasive strategy for dynamic MRI (dMRI) of awake rabbits during carbogen challenge. METHODS: A nonmetallic assistive device with a self-adhering wrap secure procedure was developed for the head fixation of awake rabbits. Multi-shot gradient echo echo-planar imaging sequence was applied for the dMRI on a 1.5 T clinical MRI scanner with a quadrature head coil. The carbogen challenge pattern was applied in a sequence of air - carbogen - air - carbogen - air. Twelve scans were performed for each block of carbogen challenge. T2-weighted fast-spin echo and T1-weighted gradient echo sequences were performed before and after dMRI to evaluate the head position shifts. The whole dMRI scan time was about 30 minutes. RESULTS: The position shift of 8 rabbits in the x-and y-direction was less than 3%. The average MRI signal intensities (SI) from the 8 rabbits during carbogen challenge was fitted well using exponential growth and decay functions. The average MRI SI increase due to carbogen inhaling was 1.51%. CONCLUSIONS: The proposed strategy for head dMRI on an awake rabbit during carbogen challenge is feasible.

The effect of trauma backboards on computed tomography radiation dose.

AIM: To assess the effect of trauma backboards on the radiation dose at computed tomography (CT) when using automatic tube current modulation (ATCM). MATERIALS AND METHODS: An anthropomorphic phantom was scanned with two commercially available CT systems (GE LightSpeed16 Pro and Siemens Definition AS+) without and with backboards. Tube current-time product (mAs), and CTDIvol (mGy) were recorded for each examination. Thermoluminescent dosimeters were used to measure skin entrance dose in the pelvis and breast. Statistical significance was determined using a two-sample t-test. In addition, an institutional review board-approved retrospective image review was performed to quantify the frequency of backboard use during CT in the emergency department. RESULTS: There was a statistically significant increase in maximum tube current-time product (p<0.05) and CTDIvol (p<0.05) with the presence of a backboard; tube current-time product increased up to 31% and CTDIvol increased up to 27%. There was a significant increase in skin entrance dose in the anterior and posterior pelvis (p<0.05) with the presence of a backboard; skin entrance dose increased up to 25% in the anterior pelvis. Skin entrance dose to the breast increased with a backboard, although this was not statistically significant. The frequency of backboard use during CT markedly decreased (from 77% to 3%) after instituting a multidisciplinary policy to promptly remove patients from backboards upon arrival to the emergency department after a primary clinical survey. CONCLUSIONS: Using backboards during CT with ATCM can significantly increase the radiation dose. Although the decision to maintain patients on backboards is multifactorial, attempts should be made to minimise backboard use during CT when possible.

Changes in Physiologic Parameters and Effects of Hooding in Red-tailed Hawks ( Buteo jamaicensis ) During Manual Restraint.

Manual restraint in birds of prey is required for many veterinary and research procedures. To investigate the effects of handling stress on physiologic parameters in raptorial birds, 8 red-tailed hawks ( Buteo jamaicensis ) were manually restrained over a 15-minute period. Respiratory rate (RR), heart rate (HR), and cloacal temperature were monitored over time and recorded at defined intervals during the experiment. The effect of hooding on physiologic variables was also evaluated in a complete crossover design. Both RR and HR decreased significantly during the 15-minute restraint period (HR, -80 ± 101.4 beats/min [bpm], [P < .01]; RR, -17.5 ± 22.6 breaths/min, [P < .05]). Hooded birds had significantly lower HRs and RRs at 15 minutes of restraint (HR: 232.5 ± 26 bpm, [P < .037]; RR: 33.1 ± 6.7 breaths/min, [P < .05]) compared to birds restrained without a hood (HR: 280 ± 74.1 bpm; RR: 51.5 ± 28.8 breaths/min). Cloacal temperature increased significantly in all manually restrained birds (+2.2 ± 0.7°C, [P < .01]), with a comparable increase in hooded and nonhooded birds. In this study of the effects of manual restraint on red-tailed hawks, hooding versus nonhooding amplified the decrease in HR and RR but had no effect on stress-induced hyperthermia.

Cerebellar-dependent expression of motor learning during eyeblink conditioning in head-fixed mice.

Eyeblink conditioning in restrained rabbits has served as an excellent model of cerebellar-dependent motor learning for many decades. In mice, the role of the cerebellum in eyeblink conditioning is less clear and remains controversial, partly because learning appears to engage fear-related circuits and lesions of the cerebellum do not abolish the learned behavior completely. Furthermore, experiments in mice are performed using freely moving systems, which lack the stability necessary for mapping out the essential neural circuitry with electrophysiological approaches. We have developed a novel apparatus for eyeblink conditioning in head-fixed mice. Here, we show that the performance of mice in our apparatus is excellent and that the learned behavior displays two hallmark features of cerebellar-dependent eyeblink conditioning in rabbits: (1) gradual acquisition; and (2) adaptive timing of conditioned movements. Furthermore, we use a combination of pharmacological inactivation, electrical stimulation, single-unit recordings, and targeted microlesions to demonstrate that the learned behavior is completely dependent on the cerebellum and to pinpoint the exact location in the deep cerebellar nuclei that is necessary. Our results pave the way for using eyeblink conditioning in head-fixed mice as a platform for applying next-generation genetic tools to address molecular and circuit-level questions about cerebellar function in health and disease.

Design of a mouse restraint for synchrotron-based computed tomography imaging.

High-resolution computed tomography (CT) imaging of a live animal within a lead-lined synchrotron light hutch presents several unique challenges. In order to confirm that the animal is under a stable plane of anaesthesia, several physiological parameters (e.g. heart rate, arterial oxygen saturation, core body temperature and respiratory rate) must be remotely monitored from outside the imaging hutch. In addition, to properly scan the thoracic region using CT, the animal needs to be held in a vertical position perpendicular to the fixed angle of the X-ray beam and free to rotate 180°-360°. A new X-ray transparent mouse restraint designed and fabricated using computer-aided design software and three-dimensional rapid prototype printing has been successfully tested at the Biomedical Imaging and Therapy bending-magnet (BMIT-BM) beamline at the Canadian Light Source.

Quantifying lingual coarticulation using ultrasound imaging data collected with and without head stabilisation.

Previous studies reporting the use of ultrasound tongue imaging with clinical populations have generally provided qualitative information on tongue movement. Meaningful quantitative measures for use in the clinic typically require the speaker's head to be stabilised in relation to a transducer, which may be uncomfortable, and unsuitable for young children. The objective of this study was to explore the applicability of quantitative measurements of stabilisation-free tongue movement data, by comparing ultrasound data collected from 10 adolescents, with and without head stabilisation. Several measures of tongue shape were used to quantify coarticulatory influence from two contrasting vowels on four different consonants. Only one of the measures was completely unaffected by the stabilisation condition for all the consonants. The study also reported cross-consonant differences in vowel-related coarticulatory effects. The implications of the findings for the theory of coarticulation and for potential applications of stabilisation-free tongue curve measurements in clinical studies are discussed.

High precision anatomy for MEG.

Precise MEG estimates of neuronal current flow are undermined by uncertain knowledge of the head location with respect to the MEG sensors. This is either due to head movements within the scanning session or systematic errors in co-registration to anatomy. Here we show how such errors can be minimized using subject-specific head-casts produced using 3D printing technology. The casts fit the scalp of the subject internally and the inside of the MEG dewar externally, reducing within session and between session head movements. Systematic errors in matching to MRI coordinate system are also reduced through the use of MRI-visible fiducial markers placed on the same cast. Bootstrap estimates of absolute co-registration error were of the order of 1mm. Estimates of relative co-registration error were <1.5mm between sessions. We corroborated these scalp based estimates by looking at the MEG data recorded over a 6month period. We found that the between session sensor variability of the subject's evoked response was of the order of the within session noise, showing no appreciable noise due to between-session movement. Simulations suggest that the between-session sensor level amplitude SNR improved by a factor of 5 over conventional strategies. We show that at this level of coregistration accuracy there is strong evidence for anatomical models based on the individual rather than canonical anatomy; but that this advantage disappears for errors of greater than 5mm. This work paves the way for source reconstruction methods which can exploit very high SNR signals and accurate anatomical models; and also significantly increases the sensitivity of longitudinal studies with MEG.

The helmet head restraint system: a viable solution for resting state fMRI in awake monkeys.

In monkey neuroimaging, head restraint is currently achieved via surgical implants. Eradicating such invasive head restraint from otherwise non-invasive monkey studies could represent a substantial progress in terms of Reduction and Refinement. Two non-invasive helmet-based methods are available but they are used exclusively by the pioneering research groups who designed them. In the absence of independent replication, they have had little impact in replacing the surgical implants. Here, we built a modified version of the helmet system proposed by Srihasam et al. (2010 NeuroImage, 51(1), 267-73) and tested it for resting state fMRI in awake monkeys. Extremely vulnerable to motion artifacts, resting state fMRI represents a decisive test for non-invasive head restraint systems. We compared two monkeys restrained with the helmet to one monkey with a surgically implanted head post using both a seed-based approach and an independent component analysis. Technically, the helmet system proved relatively easy to develop. Scientifically, although it allowed more extensive movements than the head post system, the helmet proved viable for resting state fMRI, in particular when combined with the independent component analysis that deals more effectively with movement-related noise than the seed-based approach. We also discuss the pros and cons of such device in light of the European Union new 2013 regulation on non-human primate research and its firm Reduction and Refinement requests.

High frequency of potential entrapment gaps in beds in an acute hospital.

OBJECTIVE: dimensional guidelines for bedrails have been developed to minimise the risk of patient entrapment within the bed. We examined whether bedrails in a large Irish teaching hospital complied with these standards. DESIGN AND SETTING: survey of 60 accessible beds in six hospital wards. METHODS: a specialised cone and cylinder tool that mimics the size and weight of a small adult neck and head was used to determine gaps in the four zones most associated with entrapment. RESULTS: the number of failures for each zone was 15 beds for zone 1 (any space between the perimeters of the rail); 42 beds for zone 2 (the space under the rail); 41 beds for zone 3 (the space between the inside surface of the bedrail and the mattress) and 13 beds for zone 4 (the space between the mattress and rail at the end of the rail). Failures were more common with hydraulic adjusted than with electric profiling beds. Mattresses that were the wrong size (usually too narrow) or too soft and bedrails that were loose or were poorly maintained accounted for many failures. CONCLUSION: many beds used in our hospital did not comply with dimensional standards to minimise entrapment risks. This emphasises the need for careful selection of patients for whom bedrails are to be used as well as the need for monitoring and maintenance of bed systems.