Comparison of the forearm rotation restriction capacities of four upper-extremity immobilization methods: there is no difference between single and double sugar tong splinting.

BACKGROUND: The aim of this study was to compare the effects of four different immobilization methods [single sugar tong splint (SSTS), double sugar tong splint (DSTS), short arm cast (SAC), and long arm cast (LAC)] commonly used for restricting forearm rotation in the upper extremity. METHODS: Forty healthy volunteers were included in the study. Dominant extremities were used for measurements. Basal pronation and supination of the forearm were measured with a custom-made goniometer, and the total rotation arc was calculated without any immobilization. Next, the measurements were repeated with the SAC, LAC, SSTS and DSTS. Each measurement was compared to the baseline value, and the percentage of rotation restriction was calculated. RESULTS: The most superior restriction rates were observed for the LAC (p = 0.00). No statistically significant difference was detected between the SSTS and DSTS in terms of the restriction of supination, pronation or the rotation arc (p values, 1.00, 0.18, and 0.50, respectively). Statistically significant differences were not detected between the SAC and the SSTS in any of the three parameters (p values, 0.25; 1.00; 1.00, respectively). When the SAC and DSTS were compared, while there was no significant difference between the two methods in pronation (p = 0.50), a statistically significant difference was detected in supination (p = 0.01) and in the total rotation arc (p = 0.03). CONCLUSION: The LAC provides superior results in restricting forearm rotation. The SAC and SSTS had similar effects on forearm rotation. The DSTS, which contains, in addition to the SSTS, a sugar tong portion above the elbow, does not provide additional rotational stability.

MRgFUS ablation of a recurrent tenosynovial giant cell tumor in the foot using ExAblate 2100 system in combination with patient immobilization device.

INTRODUCTION: Magnetic Resonance-guided Focused Ultrasound (MRgFUS) treatment for certain anatomy locations can be extremely challenging due to patient positioning and potential motion. This present study describes the treatment of a recurrent tenosynovial giant cell tumor of the plantar forefoot using the ExAblate 2100 system in combination with patient immobilization device. METHODS: Prior to the treatment, several patient immobilization devices were investigated. Vacuum cushions were selected and tested for safety and compatibility with the treatment task and the MR environment. RESULTS: During the treatment, one vacuum cushion immobilized the patient's right leg in knee flexion and allowed the bottom of the foot to be securely positioned on the treatment window. Another vacuum cushion supported the patient upper body extended outside the scanner bore. 19 sonications were successfully executed. The treatment was judged to be successful. No immediate complications were observed. CONCLUSIONS: MRgFUS treatment of a recurrent tenosynovial giant cell tumor of the right plantar forefoot was successful with the use of patient immobilization vacuum cushions. IMPLICATIONS FOR PRACTICE: The immobilization system could be utilized to aid future MRgFUS treatment of lesions in challenging anatomic locations. Various sizes of the vacuum cushions are available to potentially better accommodate other body parts and treatment configurations.

Immobilization in External Rotation Versus Arthroscopic Stabilization After Primary Anterior Shoulder Dislocation: A Systematic Review of Level 1 and 2 Studies.

BACKGROUND: Arthroscopic stabilization has been established as a superior treatment option for primary glenohumeral instability when compared with immobilization in internal rotation. However, immobilization in external rotation (ER) has recently gained interest as a viable nonoperative treatment option for patients with shoulder instability. PURPOSE: To compare the rates of recurrent instability and subsequent surgery in patients undergoing treatment for primary anterior shoulder dislocation with arthroscopic stabilization versus immobilization in ER. STUDY DESIGN: Systematic review; Level of evidence, 2. METHODS: A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify studies that'evaluated patients being treated for primary anterior glenohumeral dislocation with either arthroscopic stabilization or immobilization in ER. The search phrase used various combinations of the keywords/phrases "primary closed reduction,""anterior shoulder dislocation,""traumatic,""primary,""treatment,""management,""immobilization,""external rotation,""surgical,""operative,""nonoperative," and "conservative." Inclusion criteria included patients undergoing treatment for primary anterior glenohumeral joint dislocation with either immobilization in ER or arthroscopic stabilization. Rates of recurrent instability, subsequent stabilization surgery, return to sports, positive postintervention apprehension tests, and patient-reported outcomes were evaluated. RESULTS: The 30 studies that met inclusion criteria included 760 patients undergoing arthroscopic stabilization (mean age, 23.1 years; mean follow-up time, 55.1 months) and 409 patients undergoing immobilization in ER (mean age, 29.8 years; mean follow-up time, 28.8 months). Overall, 8.8% of operative patients experienced recurrent instability at latest follow-up compared with 21.3% of patients who had undergone ER immobilization (P < .0001). Similarly, 5.7% of operative patients had undergone a subsequent stabilization procedure at latest follow-up compared with 11.3% of patients who had undergone ER immobilization (P = .0015). A higher rate of return to sports was found in the operative group (P < .05), but no other differences were found between groups. CONCLUSION: Patients undergoing arthroscopic treatment for primary anterior glenohumeral dislocation with arthroscopic stabilization can be expected to experience significantly lower rates of recurrent instability and subsequent stabilization procedures compared with patients undergoing ER immobilization.

"Superhero" concept to avoid anesthesia for daily radiation treatment in childhood cancer.

Advancements in therapeutic interventions have led to significant improvement in the overall management of childhood cancer. Radiotherapy forms an important component of their treatment. Modern radiotherapy technique where an optimal therapeutic ratio can be obtained demands proper and adequate immobilization of the child. This can be technically challenging sometimes, particularly when the child is noncompliant. To address this hurdle, we have used this concept of "Superhero," where we have decorated and painted the thermoplastic masks that often used in the head and neck and cranial irradiation. We have received adequate compliance for this method, and the need for anesthesia was slackened.

Vicia faba Peptide Network Supplementation Does Not Differ From Milk Protein in Modulating Changes in Muscle Size During Short-Term Immobilization and Subsequent Remobilization, but Increases Muscle Protein Synthesis Rates During Remobilization in Healthy Young Men.

BACKGROUND: Muscle mass and strength decrease during short periods of immobilization and slowly recover during remobilization. Recent artificial intelligence applications have identified peptides that appear to possess anabolic properties in in vitro assays and murine models. OBJECTIVES: This study aimed to compare the impact of Vicia faba peptide network compared with milk protein supplementation on muscle mass and strength loss during limb immobilization and regain during remobilization. METHODS: Thirty young (24 ± 5 y) men were subjected to 7 d of one-legged knee immobilization followed by 14 d of ambulant recovery. Participants were randomly allocated to ingest either 10 g of the Vicia faba peptide network (NPN_1; n = 15) or an isonitrogenous control (milk protein concentrate; MPC; n = 15) twice daily throughout the study. Single-slice computed tomography scans were performed to assess quadriceps cross-sectional area (CSA). Deuterium oxide ingestion and muscle biopsy sampling were applied to measure myofibrillar protein synthesis rates. RESULTS: Leg immobilization decreased quadriceps CSA (primary outcome) from 81.9 ± 10.6 to 76.5 ± 9.2 cm2 and from 74.8 ± 10.6 to 71.5 ± 9.8 cm2 in the NPN_1 and MPC groups, respectively (P < 0.001). Remobilization partially recovered quadriceps CSA (77.3 ± 9.3 and 72.6 ± 10.0 cm2, respectively; P = 0.009), with no differences between the groups (P > 0.05). During immobilization, myofibrillar protein synthesis rates (secondary outcome) were lower in the immobilized leg (1.07% ± 0.24% and 1.10% ± 0.24%/d, respectively) than in the non-immobilized leg (1.55% ± 0.27% and 1.52% ± 0.20%/d, respectively; P < 0.001), with no differences between the groups (P > 0.05). During remobilization, myofibrillar protein synthesis rates in the immobilized leg were greater with NPN_1 than those with MPC (1.53% ± 0.38% vs. 1.23% ± 0.36%/d, respectively; P = 0.027). CONCLUSION: NPN_1 supplementation does not differ from milk protein in modulating the loss of muscle size during short-term immobilization and the regain during remobilization in young men. NPN_1 supplementation does not differ from milk protein supplementation in modulating the myofibrillar protein synthesis rates during immobilization but further increases myofibrillar protein synthesis rates during remobilization.

Cervical Spinal Immobilization: A Head-to-Head Comparison of a One-Step Spray-on Foam Splint Versus Structural Aluminum Malleable Splint Immobilization.

INTRODUCTION: Cervical spine immobilization in a low-resource environment is difficult secondary to limited equipment, prolonged transportation, and secondary complications. A structural aluminum malleable (SAM) splint is commonly utilized because of its availability and multipurpose intention. A one-step spray-on foam immobilization technique (Fast Cast) has been shown to be effective in lower-extremity splinting. The aim of this study was to demonstrate the ability of the Fast Cast to effectively immobilize the cervical spine in a head-to-head comparison against the SAM splint. We hypothesized that there would be no difference in surgeon scoring between Fast Cast and SAM splints for the immobilization of the cervical spine. METHODS: This was a cadaveric experimental comparative study that compared a SAM splint versus Fast Cast for the immobilization of an unstable cervical spine. Each of the three cadaveric specimens had a corpectomy without fixation performed. A board-certified emergency medicine physician specialized in disaster medicine performed all SAM immobilizations. An orthopedic surgeon performed Fast Cast immobilizations. Each method of immobilization was done on each cadaver. Lateral fluoroscopic imaging was taken before and after immobilization and after log roll/gravity stress. Five board-certified orthopedic surgeons served as graders to independently score each splint. A 5-point Likert scale based on 10 splinting criteria (50 total points possible) was utilized to evaluate cervical spine immobilization. The lead statistical analyst was blinded to the immobilization groups. The statistical significance was assessed via a Wilcoxon signed-rank test and chi-square Fisher's exact test with significance between groups set at α < .05. Inter-rater reliability of the Likert scale results was assessed with the interclass correlation coefficient. RESULTS: Inter-rater reliability for the current Likert scale in the evaluation of cervical spine stabilization was good (interclass correlation coefficient = 0.76). For the cumulative Likert scale score, Fast Cast (32 [28-34]) exhibited a higher total score than SAM (44 [42-47]; P < .01). Likewise, Fast Cast exhibited a greater likelihood of higher Likert scores within each individual question as compared to SAM (P ≤ 0.04). In 100% of cases, raters indicated that Fast Cast passed the gravity stress examination without intrinsic loss of reduction or splinting material, whereas 33% of SAM passed (P < .01). In 100% of cases, raters indicated that Fast Cast passed the initial radiographic alignment following immobilization, whereas 66% of SAM passed (P = .04). In 100% of cases, raters indicated that Fast Cast passed radiographic alignment after the gravity stress examination, whereas 47% of SAM passed (P < .01). CONCLUSION: The Fast Cast exceeded our expectations and was shown to be rated not equivalent but superior to SAM splint immobilization for the cervical spine. This has significant clinical implications as the single-step spray-on foam is easy to transport and has multifaceted applications. It also eliminates pressure points and circumferential wrapping and obstruction to airway/vascular access while immobilizing the cervical spine and allowing for radiographic examination. Further studies are needed for human use and application.

A simple and low-cost technic for immobilization of mandible during head and heck radiotherapy: a technical note.

Immobilization protocols for head and neck radiotherapy (HNR) are needed to reduce radiation dispersion in non-tumoral tissues and to reduce damage to noble structures; however, involuntary mandibular movements require additional adaptations of thermoplastic masks. PURPOSE: Our objective was to describe an easy and low-cost disposition to help thermoplastic masks immobilize the mandible during HNR. MATERIALS AND METHODS: We created Styrofoam models to stabilize the mandible which was used to make adaptation to the thermoplastic masks. The Styrofoam model was inserted into alginate to construct a mold and a self-curing acrylic resin was added into the mold. After the acrylic resin hardened, the dispositive mandibular immobilizer was removed from the alginate mold and adjusted with Maxicut and Minicut or other drills and sandpaper. The alginate mold can be used on the same day to create backup devices. RESULTS AND CONCLUSIONS: Our device was made in a simple way, has a low cost, and helps the thermoplastic masks to immobilize the mandible, leading to a more precise individualization of head and neck immobilization that can reduce unanticipated radiation scatter and improve radiation distribution.

Comparison of setup accuracy and efficiency between the Klarity system and BodyFIX system for spine stereotactic body radiation therapy.

BACKGROUND: Spine stereotactic body radiation therapy (SBRT) uses highly conformal dose distributions and sharp dose gradients to cover targets in proximity to the spinal cord or cauda equina, which requires precise patient positioning and immobilization to deliver safe treatments. AIMS: Given some limitations with the BodyFIX system in our practice, we sought to evaluate the accuracy and efficiency of the Klarity SBRT patient immobilization system in comparison to the BodyFIX system. METHODS: Twenty-three patients with 26 metastatic spinal lesions (78 fractions) were enrolled in this prospective observational study with one of two systems - BodyFIX (n = 11) or Klarity (n = 12). All patients were initially set up to external marks and positioned to match bony anatomy on ExacTrac images. Table corrections given by ExacTrac during setup and intrafractional monitoring and deviations from pre- and posttreatment CBCT images were analyzed. RESULTS: For initial setup accuracy, the Klarity system showed larger differences between initial skin mark alignment and the first bony alignment on ExacTrac than BodyFIX, especially in the vertical (mean [SD] of 5.7 mm [4.1 mm] for Klarity vs. 1.9 mm [1.7 mm] for BodyFIX, p-value < 0.01) and lateral (5.4 mm [5.1 mm] for Klarity vs. 3.2 mm [3.2 mm] for BodyFIX, p-value 0.02) directions. For set-up stability, no significant differences (all p-values > 0.05) were observed in the maximum magnitude of positional deviations between the two systems. For setup efficiency, Klarity system achieved desired bony alignment with similar number of setup images and similar setup time (14.4 min vs. 15.8 min, p-value = 0.41). For geometric uncertainty, systematic and random errors were found to be slightly less with Klarity than with BodyFIX based on an analytical calculation. CONCLUSION: With image-guided correction of initial alignment by external marks, the Klarity system can provide accurate and efficient patient immobilization. It can be a promising alternative to the BodyFIX system for spine SBRT while providing potential workflow benefits depending on one's practice environment.

The Immo Traffic Light System as a Decision-Making Tool for Prehospital Spinal Immobilization­A Systematic Review

BACKGROUND: Spinal injuries are difficult injuries to assess yet can be associated with significant neurological damage. To avoid secondary damage, immobilization is considered state of the art trauma care. The indication for spinal immobilization must be assessed, however, for potential complications as well as its advantages and disadvantages. METHODS: This systematic review addressing the question of the correct indication for spinal immobilization in trauma patients was compiled on the basis of our previously published analysis of possible predictors from the Trauma Registry of the German Society for Trauma Surgery. A Delphi procedure was then used to develop suggestions for action regarding immobilization based on the results of this review. RESULTS: The search of the literature yielded 576 publications. The 24 publications included in the qualitative analysis report of 2 228 076 patients. A decision tool for spinal immobilization in prehospital trauma care was developed (Immo traffic light system) based on the results of the Delphi procedure. According to this system, severely injured patients with blunt trauma, severe traumatic brain injury, peripheral neurological symptoms, or spinal pain requiring treatment should be immobilized. Patients with a statistically increased risk of spinal injury as a result of the four cardinal features (fall >3m, severe trunk injury, supra clavicular injury, seniority [age >65 years]) should only have their spinal motion restricted after weighing up the pros and cons. Isolated penetrating trunk injuries should not be immobilized. CONCLUSION: High-quality studies demonstrating the benefit of prehospital spinal immobilization are still lacking. Decision tools such as the Immo traffic light system can help weigh up the pros and cons of immobilization.

Development of a device that remotely removes a mask in the head and neck immobilization system: a prototype and demonstration experiment.

In this study, a prototype device was developed to quickly remove the mask used to immobilize the head and neck by remotely releasing the quick fasteners. As a first step in investigating the usefulness of this prototype, we performed repeated removal tests and examined the accuracy of dose calculation. The results showed that the quick-release fasteners of a Type-S system (CIVCO Medical Solutions, Iowa, USA) could be removed remotely and accurately (success rate: 100%). Additionally, the dose errors in treatment planning were negligible (< 1.0%), and the gamma pass rate was equivalent (99.9%). Therefore, this prototype device with a remote system would help manage patient safety in emergencies, such as a disaster or a sudden change in the patient's condition. However, age-related deterioration with long-term clinical use or its ability to link with beam-off still requires further exploration.

Evaluation of novel 3D-printed and conventional thermoplastic stereotactic high-precision patient fixation masks for radiotherapy.

PURPOSE: For stereotactic radiation therapy of intracranial malignancies, a patient's head needs to be immobilized with high accuracy. Fixation devices such as invasive stereotactic head frames or non-invasive thermoplastic mask systems are often used. However, especially stereotactic high-precision masks often cause discomfort for patients due to a long manufacturing time during which the patient is required to lie still and because the face is covered, including the mouth, nose, eyes, and ears. To avoid these issues, the target was to develop a non-invasive 3D-printable mask system with at least the accuracy of the high-precision masks, for producing masks which can be manufactured in the absence of patients and which allow the eyes, mouth, and nose to be uncovered during therapy. METHODS: For four volunteers, a personalized 3D-printed mask based on magnetic resonance imaging (MRI) data was designed and manufactured using fused filament fabrication (FFF). Additionally, for each of the volunteers, a conventional thermoplastic stereotactic high-precision mask from Brainlab AG (Munich, Germany) was fabricated. The intra-fractional fixation accuracy for each mask and volunteer was evaluated using the motion-correction algorithm of functional MRI measurements with and without guided motion. RESULTS: The average values for the translations and rotations of the volunteers' heads lie in the range between ±1 mm and ±1° for both masks. Interestingly, the standard deviations and the relative and absolute 3D displacements are lower for the 3D-printed masks compared to the Brainlab masks. CONCLUSION: It could be shown that the intra-fractional fixation accuracy of the 3D-printed masks was higher than for the conventional stereotactic high-precision masks.

Initial clinical experience of surface guided stereotactic radiation therapy with open-face mask immobilization for improving setup accuracy: a retrospective study.

PURPOSE: To propose a specific surface guided stereotactic radiotherapy (SRT) treatment procedure with open-face mask immobilization and evaluate the initial clinical experience in improving setup accuracy. METHODS AND MATERIALS: The treatment records of 48 SRT patients with head lesions were retrospectively analyzed. For each patient, head immobilization was achieved with a double-shell open-face mask. The anterior shell was left open to expose the forehead, nose, eyes and cheekbones. The exposed facial area was used as region-of-interest for surface tracking by AlignRT (VisionRT Inc, UK). The posterior shell provided a sturdy and personalized headrest. Patient initial setup was guided by 6DoF real-time deltas (RTD) using the reference surface obtained from the skin contour delineated on the planning CT images. The endpoint of initial setup was 1 mm in translational RTD and 1 degree in rotational RTD. CBCT guidance was performed to derive the initial setup errors, and couch shifts for setup correction were applied prior to treatment delivery. CBCT couch shifts, AlignRT RTD values, repositioning rate and setup time were analyzed. RESULTS: The absolute values of median (maximal) CBCT couch shifts were 0.4 (1.3) mm in VRT, 0.1 (2.5) mm in LNG, 0.2 (1.6) mm in LAT, 0.1(1.2) degree in YAW, 0.2 (1.4) degree in PITCH and 0.1(1.3) degree in ROLL. The couch shifts and AlignRT RTD values exhibited highly agreement except in VRT and PITCH (p value < 0.01), of which the differences were as small as negligible. We did not find any case of patient repositioning that was due to out-of-tolerance setup errors, i.e., 3 mm and 2 degree. The surface guided setup time ranged from 52 to 174 s, and the mean and median time was 97.72 s and 94 s respectively. CONCLUSIONS: The proposed surface guided SRT procedure with open-face mask immobilization is a step forward in improving patient comfort and positioning accuracy in the same process. Minimized initial setup errors and repositioning rate had been achieved with reasonably efficiency for routine clinical practice.

Comparison of intrafractional motion with two frameless immobilization systems in surface-guided intracranial stereotactic radiosurgery.

PURPOSE/OBJECTIVES: The aim of this study is to compare intrafractional motion using two commercial non-invasive immobilization systems for linac-based intracranial stereotactic radiosurgery (SRS) under guidance with a surface-guided radiotherapy (SGRT) system. MATERIALS/METHODS: Twenty-one patients who received intracranial SRS were retrospectively selected. Ten patients were immobilized with a vacuum fixation biteplate system, while 11 patients were immobilized with an open-face mask system. A setup margin of 1 mm was used in treatment planning. Real-time surface motion data in 37 treatment fractions using the vacuum fixation system and 44 fractions using the open-face mask were recorded by an SGRT system. Variances of intrafractional motion along three translational directions and three rotational directions were compared between the two immobilization techniques with Levene's tests. Intrafractional motion variation over time during treatments was also evaluated. RESULTS: Using the vacuum fixation system, the average and standard deviations of the shifts were 0.01 ± 0.18 mm, -0.06 ± 0.30 mm, and  0.02 ± 0.26 mm in the anterior-posterior (AP), superior-inferior (SI), and left-right (LR) directions, and -0.02 ± 0.19°, -0.01 ± 0.13°, and 0.01 ± 0.13° for rotations in yaw, roll, and pitch, respectively; using the open-face mask system, the average and standard deviations of the shifts were -0.06 ± 0.20 mm, -0.02 ± 0.35 mm, and 0.01 ± 0.40 mm in the AP, SI, and LR directions, and were 0.05 ± 0.23°, 0.02 ± 0.21°, and 0.00 ± 0.16° for rotations in yaw, roll, and pitch, respectively. There was a significant increase in intrafractional motion variance over time during treatments. CONCLUSION: Patients with the vacuum fixation system had significantly smaller intrafractional motion variation compared to those with the open-face mask system. Using intrafractional motion techniques such as surface imaging system is recommended to minimize dose deviation due to intrafractional motion. The increase in intrafractional motion over time indicates clinical benefits with shorter treatment time.

Postoperative immobilization using a short-arm cast in the semisupination position is appropriate after arthroscopic triangular fibrocartilage complex foveal repair.

AIMS: The aim of this study was to assess and compare active rotation of the forearm in normal subjects after the application of a short-arm cast (SAC) in the semisupination position and a long-arm cast (LAC) in the neutral position. A clinical study was also conducted to compare the functional outcomes of using a SAC in the semisupination position with those of using a LAC in the neutral position in patients who underwent arthroscopic triangular fibrocartilage complex (TFCC) foveal repair. METHODS: A total of 40 healthy right-handed volunteers were recruited. Active pronation and supination of the forearm were measured in each subject using a goniometer. In the retrospective clinical study, 40 patients who underwent arthroscopic foveal repair were included. The wrist was immobilized postoperatively using a SAC in the semisupination position (approximately 45°) in 16 patients and a LAC in 24. Clinical outcomes were assessed using grip strength and patient-reported outcomes. The degree of disability caused by cast immobilization was also evaluated when the cast was removed. RESULTS: Supination was significantly more restricted with LACs than with SACs in the semisupination position in male and female patients (p < 0.001 for both). However, pronation was significantly more restricted with SACs in the semisupination position than with LACs in female patients (p = 0.003) and was not significantly different in male patients (p = 0.090). In the clinical study, both groups showed improvement in all parameters with significant differences in grip strength, visual analogue scale scores for pain, modified Mayo Wrist Score, the Disability of the Arm, Shoulder, and Hand (DASH) score, and the Patient-Rated Wrist Evaluation (PRWE) score. No significant postoperative differences were noted between LACs and SACs in the semisupination position. However, the disability caused by immobilization in a cast was significantly higher in patients who had a LAC on the dominant hand (p < 0.001). CONCLUSION: We found that a SAC in the semisupination position is as effective as a LAC in restricting pronation of the forearm. In addition, postoperative immobilization with a SAC in the semisupination position resulted in comparable pain scores and functional outcomes to immobilization with a LAC after TFCC foveal repair, with less restriction of daily activities. Therefore, we recommend that surgeons consider using a SAC in the semisupination position for postoperative immobilization following TFCC foveal repair for dorsal instability of the distal radioulnar joint. Cite this article: Bone Joint J 2022;104-B(2):249-256.

Unmasking a Privacy Concern: Potential Identification of Patients in an Immobilization Mask from 3-Dimensional Reconstructions of Simulation Computed Tomography.

Previous studies have demonstrated that patients can be identified from 3-dimensional (3D) reconstructions of computed tomography (CT) or magnetic resonance imaging data of the brain or head and neck. This presents a privacy and security concern for scan data released to public data sets. It is unknown whether thermoplastic immobilization masks used for treatment planning in radiation therapy are sufficient to prevent facial recognition. Our study sought to evaluate whether patients with an immobilization mask could be identified on 3D reconstructions of scan data. Our study reconstructed 3D images from simulation CT (SIM-CT) scans of 35 patients and compared these to original patient photographs to test if the thermoplastic mask obfuscated facial features. Blind review from 4 facial recognition algorithms and a human (radiation oncologist) was evaluated for the ability to match 3D reconstructions of patients scans to patient images. The matching procedure was repeated against an expanded testing data set of the 35 patient photographs plus 13,233 facial photographs from the "Labeled Faces in the Wild" data set (13,268 photographs in total). Facial recognition algorithms were able to match a maximum of 83% (range, 60%-83%) of patients to the corresponding images. Radiation Oncologist blinded review correctly matched 80% of patients to the corresponding images. Ethnicity and facial hair were the most common reasons for patient mismatch. In the expanded testing data set, algorithms were also able to match a maximum of 83% (range, 57%-83%) of patients. The majority of patients were able to be identified through computer algorithm or human review even under a SIM-CT mask. These results suggest there is a potential privacy and security concern when SIM-CT data are released to publicly available data sets.

Results after spica cast immobilization following hip reconstruction in 95 cases: is there a need for alternative techniques?

INTRODUCTION: Developmental dysplasia of the hip (DDH), neurogenic dysplasia of the hip (NDH), and Perthes disease often require surgical treatment. Spica casting is a common postoperative immobilization. The purpose of this study was to evaluate the complications related to the immobilization. MATERIALS AND METHODS: In a retrospective analysis, we included 83 patients (95 hips), who underwent hip reconstructive surgery between 2008 and 2018. We had 43 female and 40 male patients. Age reached from 3 months to 19 years. All patients were treated with a spica cast postoperatively for a 6-week protocol. Complications were analyzed using the full medical documentation and classified according to Clavien-Dindo. RESULTS: We had complications in 23 patients (27.7%). We counted superficial skin lesions in seven, deep skin lesions in three, spasticity of adductors in three, subluxation in two, infection of the plate in one, fracture of the plate in one, compliance problem in one, dislocations of the cast in two, reluxation in one, delayed bone healing in one and spasticity of knee flexors in one case. According to the classification of Clavien-Dindo, we were able to count ten type I, four type II, nine type III, zero type IV and zero type V adverse events. CONCLUSION: The usage of a spica cast after hip reconstructive surgery is still the most popular way of aftertreatment. It has a low complication rate, which may be lowered by well-applied casts and foam padding. Known complications such as spasticity in patients with cerebral palsy, skin lesions, and pressure sores should be observed and avoided. Shorter protocols for immobilization with the usage of foam padding and foam splints lead to less complications. CLINICAL RELEVANCE: Evidence level level IV, case series.

Evaluation of the inter- and intrafraction displacement for head patients treated at the particle therapy centre MedAustron based on the comparison of different commercial immobilisation devices.

In December 2016 the clinical operation has started at the particle therapy centre MedAustron, Wiener Neustadt, Austria. Different commercial immobilisation devices are used for head patients. These immobilisation devices are a combination of table tops (Qfix BoS™ Headframe, Elekta HeadStep™), pillows (BoS™ Standard pillow, Moldcare®, HeadStep™ pillow) and thermoplastic masks (Klarity Green™, Qfix Fibreplast™, HeadStep™ iCAST double). For each patient image-guided radiotherapy (IGRT) is performed by acquiring orthogonal X-ray imaging and 2D3D registration and the application of the resulting 6-degree of freedom (DOF) position correction on the robotic couch. The inter- and intrafraction displacement of 101 adult head patients and 27 paediatric sedated head patients were evaluated and compared among each other regarding reproducibility during the entire treatment and stability during each fraction. For the comparison, statistical methods (Shapiro-Wilk test, Mann-Whitney U-test) were applied on the position corrections as well as on the position verifications. The actual planning target volume margins of 3mm (adults) and 2mm (children) were evaluated by applying the van Herk formula on the intrafraction displacement results and performing treatment plan robustness simulations of twelve different translational offset scenarios including a HU uncertainty of 3.5%. Statistically significant differences between the immobilisation devices were found, but they turned out to be clinically irrelevant. The margin calculation for adult head patients resulted in 0.8mm (lateral), 1.2mm (cranio-caudal) and 0.6mm (anterior-posterior), and for paediatric head patients under anaesthesia in 0.8mm (lateral), 0.5mm (cranio-caudal) and 0.9mm (anterior-posterior). Based on these values, robustness evaluations of selected adult head patients and sedated children showed the validity of the currently used PTV margins.

Evaluation of setup errors of immobilization device for radiation therapy in companion animals.

Background: Intensity-modulated radiotherapy (IMRT), which allows generating steep dose gradients, is a beneficial treatment for companion animals with adjacent target and risk organs. IMRT is essential for high setup accuracy for avoiding overdose to risk organs, and optimal radiotherapy is important for evaluating the setup accuracy of companion animals. Aim: To use an immobilization device to evaluate setup errors in radiotherapy for companion animals. Methods: We calculated setup errors in radiotherapy for 386 animals (dogs and cats; 3,261 registration images) that underwent radiotherapy between 2016 and 2022. The companion animals were immobilized with a customized bite block and vacuum lock device. A quantile-quantile plot with 95% confidence interval (CI) was used to evaluate the histogram of the setup errors, and the systematic and random setup errors were calculated for each region (brain, head and neck, chest and abdomen, pelvis, and spine). Results: The setup error in each direction presented an extremely narrow-interval histogram, with the following lower and upper 95% CIs: cranial-caudal (-0.08, -0.06 cm); left-right (-0.04, -0.02 cm); and dorsal-ventral (-0.13, -0.11 cm). The mean systematic setup error was 0.16 cm (range: 0.12-0.36 cm), and the random error was 0.15 cm (range: 0.08-0.34 cm). The pelvis showed the highest systematic and random setup errors (mean: 0.36 and 0.23 cm, respectively). Conclusion: The use of an immobilization device enables highly accurate radiotherapy for companion animals (95% CI < 0.15 cm).

Identification of Risk Factors for Intraoperative Acquired Pressure Injury in Patients Undergoing Neurosurgery: A Retrospective Single-Center Study.

BACKGROUND Risk factors for intraoperative acquired pressure injury (IAPI) in patients undergoing various surgical procedures have been described in previous studies. However, whether risk factors for IAPI in patients undergoing neurosurgery differ remains unknown. The aim of the present study was to explore independent risk factors for IAPI in patients undergoing neurosurgery. MATERIAL AND METHODS Data from 465 patients who underwent neurosurgery between October 2017and December 2018 and who were at high risk of IAPIs were retrospectively analyzed. Independent risk factors for IAPI were evaluated using univariate and multivariate logistic regression models. RESULTS Sixty-nine IAPIs (14.8%) in 465 patients undergoing neurosurgery were assessed. Multivariate logistic regression analyses showed that being overweight (odds ratio [OR] 2.685; 95% confidence interval [CI] 1.206-5.975; P=0.016), prone position (OR 7.502, 95% CI 2.470-22.787. P<0.001), lateral position (OR 15.301, 95% CI 4.903-47.753, P<0.001), use of a head frame (OR 3.716, 95% CI 1.431-9.653, P=0.007), surgical times of 4 to 8 h (OR 7.276, 95% CI 2.249-23.542, P<0.001), and surgical times ≥8 h (OR 173.248, 95% CI 32.629-919.896, P<0.001) all were associated with an increased risk of IAPI in patients undergoing neurosurgery. The factors associated with reduced risk of IAPI were high serum albumin levels (OR 0.099, 95% CI 0.016-0.608, P=0.013) and use of memory sponge pads (OR 0.064, 95% CI 0.020-0.202, P<0.001). CONCLUSIONS The present study indicates that being overweight, prone and lateral positioning, use of a head frame, and longer surgical times are associated with an increased risk of IAPI in patients undergoing neurosurgery. Prospective studies should be conducted to verify these findings and consideration should be given to use of these factors in clinical practice to identify high-risk patients.

Individual 3D-printed fixation masks for radiotherapy: first clinical experiences.

PURPOSE: To show the feasibility of 3D-printed fixation masks for whole brain radiation therapy in a clinical setting and perform a first comparison to an established thermoplastic mask system. METHODS: Six patients were irradiated with whole brain radiotherapy using individually 3D-printed masks. Daily image guidance and position correction were performed prior to each irradiation fraction. The vectors of the daily position correction were compared to two collectives of patients, who were irradiated using the standard thermoplastic mask system (one cohort with head masks; one cohort with head and neck masks). RESULTS: The mean systematic errors in the experimental cohort ranged between 0.59 and 2.10 mm which is in a comparable range to the control groups (0.18 mm-0.68 mm and 0.34 mm-2.96 mm, respectively). The 3D-printed masks seem to be an alternative to the established thermoplastic mask systems. Nevertheless, further investigation will need to be performed. CONCLUSION: The prevailing study showed a reliable and reproducible interfractional positioning accuracy using individually 3D-printed masks for whole brain irradiation in a clinical routine. Further investigations, especially concerning smaller target volumes or other areas of the body, need to be performed before using the system on a larger basis.