c-Axis Aligned 3 nm Thick In2O3 Crystal Using New Liquid DBADMIn Precursor for Highly Scaled FET Beyond the Mobility-Stability Trade-off.

Oxide semiconductors (OS) are attractive materials for memory and logic device applications owing to their low off-current, high field effect mobility, and superior large-area uniformity. Recently, successful research has reported the high field-effect mobility (µFE) of crystalline OS channel transistors (above 50 cm2 V-1 s-1). However, the memory and logic device application presents challenges in mobility and stability trade-offs. Here, we propose a method for achieving high-mobility and high-stability by lowering the grain boundary effect. A DBADMIn precursor was synthesized to deposit highly c-axis-aligned C(222) crystalline 3 nm thick In2O3 films. In this study, the 250 °C deposited 3 nm thick In2O3 channel transistor exhibited high µFE of 41.12 cm2 V-1 s-1, Vth of -0.50 V, and SS of 150 mV decade-1 with superior stability of 0.16 V positive shift during PBTS at 100 °C, 3 MV cm-1 stress conditions for 3 h.

Long-Term Outcome of Unilateral Acoustic Neuromas With or Without Hearing Loss: Over 10 Years and Beyond After Gamma Knife Radiosurgery.

BACKGROUND: Since the long-term outcomes of 162 patients who underwent gamma knife radiosurgery (GKS) as an initial or adjuvant treatment for acoustic neuromas (ANs) with unilateral hearing loss were first reported in 1998, there has been no report of a comprehensive analysis of what has changed in GKS practice. METHODS: We performed a retrospective study of the long-term outcomes of 106 patients with unilateral sporadic ANs who underwent GKS as an initial treatment. The mean patient age was 50 years, and the mean initial tumor volume was 3.68 cm3 (range, 0.10-23.30 cm3). The median marginal tumor dose was 12.5 Gy (range, 8.0-15.0 Gy) and the median follow-up duration was 153 months (range, 120-216 months). RESULTS: The tumor volume increased in 11 patients (10.4%), remained stationary in 27 (25.5%), and decreased in 68 patients (64.2%). The actuarial 3, 5, 10, and 15-year tumor control rates were 95.3 ± 2.1%, 94.3 ± 2.2%, 87.7 ± 3.2%, and 86.6 ± 3.3%, respectively. The 10-year actuarial tumor control rate was significantly lower in the patients with tumor volumes of ≥ 8 cm3 (P = 0.010). The rate of maintaining the same Gardner-Robertson scale grade was 28.6%, and that of serviceable hearing was 46.4%. The rates of newly developed facial and trigeminal neuropathy were 2.8% and 4.7%, respectively. The patients who received marginal doses of less than 12 Gy revealed higher tumor control failure rates (P = 0.129) and newly occurred facial or trigeminal neuropathy rates (P = 0.040 and 0.313, respectively). CONCLUSION: GKS as an initial treatment for ANs could be helpful in terms of tumor control, the preservation of serviceable hearing, and the prevention of cranial neuropathy. It is recommended to perform GKS as soon as possible not only for tumor control in unilateral ANs with hearing loss but also for hearing preservation in those without hearing loss.

Type-II Red Phosphorus: Wavy Packing of Twisted Pentagonal Tubes.

Elemental phosphorus exhibits fascinating structural varieties and versatile properties. The unique nature of phosphorus bonds can lead to the formation of extremely complex structures, and detailed structural information on some phosphorus polymorphs is yet to be investigated. In this study, we investigated an unidentified crystalline phase of phosphorus, type-II red phosphorus (RP), by combining state-of-the-art structural characterization techniques. Electron diffraction tomography, atomic-resolution scanning transmission electron microscopy (STEM), powder X-ray diffraction, and Raman spectroscopy were concurrently used to elucidate the hidden structural motifs and their packing in type-II RP. Electron diffraction tomography, performed using individual crystalline nanowires, was used to identify a triclinic unit cell with volume of 5330 Å3 , which is the largest unit cell for elemental phosphorus crystals up to now and contains approximately 250 phosphorus atoms. Atomic-resolution STEM imaging, which was performed along different crystal-zone axes, confirmed that the twisted wavy tubular motif is the basic building block of type-II RP. Our study discovered and presented a new variation of building blocks in phosphorus, and it provides insights to clarify the complexities observed in phosphorus as well as other relevant systems.

A Low-Power Analog Processor-in-Memory-Based Convolutional Neural Network for Biosensor Applications.

This paper presents an on-chip implementation of an analog processor-in-memory (PIM)-based convolutional neural network (CNN) in a biosensor. The operator was designed with low power to implement CNN as an on-chip device on the biosensor, which consists of plates of 32 × 32 material. In this paper, 10T SRAM-based analog PIM, which performs multiple and average (MAV) operations with multiplication and accumulation (MAC), is used as a filter to implement CNN at low power. PIM proceeds with MAV operations, with feature extraction as a filter, using an analog method. To prepare the input feature, an input matrix is formed by scanning a 32 × 32 biosensor based on a digital controller operating at 32 MHz frequency. Memory reuse techniques were applied to the analog SRAM filter, which is the core of low power implementation, and in order to accurately grasp the MAC operational efficiency and classification, we modeled and trained numerous input features based on biosignal data, confirming the classification. When the learned weight data was input, 19 mW of power was consumed during analog-based MAC operation. The implementation showed an energy efficiency of 5.38 TOPS/W and was differentiated through the implementation of 8 bits of high resolution in the 180 nm CMOS process.

"Fasting: An Effective Preconditioning Method to Increase Fat Graft Survival".

BACKGROUND: Most preconditioning techniques before fat grafting require external manipulation. Since nutrition is the main factor maintaining the balance of lipogenesis and lipolysis, we hypothesized that fasting before undergoing autologous fat grafting may increase lipolysis and reduce adipocyte size, thereby improving the fat graft survival rate. METHODS: C57BL/6 mice were divided into 24 h starved or fed groups. Adipose tissue lipolysis, adipogenesis, and angiogenesis-related gene expression, in fat from both groups, were analyzed. The volume and weight of the grafted fat at 4-8 weeks postoperatively were measured using micro-computed tomography. Immunohistochemistry staining and mRNA expression analysis were also performed to evaluate the effect of fasting on fat graft survival. RESULTS: Fasting decreased adipocyte size by inducing adipose tissue lipolysis. Adipogenesis-related genes were remarkably downregulated while lipolysis-related genes and angiogenesis inducer genes were significantly upregulated in the starved adipose tissue. The mice grafted with the fat from the 24 h starved group had approximately 20% larger volumes and considerably heavier weights than those from the fed group. Increased viable adipocytes and vessels, and reduced macrophages in the fat grafts obtained from the 24 h starved group were also observed. CONCLUSIONS: Fasting for 24 h before harvesting fat increased the retention volume of fat graft by increasing angiogenesis via VEGF induction. Therefore, fasting would be a novel and reliable preconditioning strategy to improve graft survival in autologous fat grafting. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

A Validated Grading Scale for Downturned Oral Commisure in Asian Faces.

BACKGROUND: Downturned oral commissures develop gradually with aging. Tools have been developed to evaluate the marionette line or the lower face. However, there is no validated and reproducible tool to evaluate the progress after oral commissure treatment in clinical practice. OBJECTIVE: The authors aimed to develop a scoring system to evaluate therapeutic interventions for downturned oral commissures and to verify its reliability, reproducibility, and clinical significance. METHODS AND MATERIALS: In the Scale Development Group, the Delphi method was used to establish a 5-graded scoring system to evaluate oral commissure position. The scoring system was applied to 50 participants. The authors recorded and compared the intrarater agreement, interrater agreement, and significance of the grade-dependent scale. RESULTS: Delphi analysis of the scoring system verified the grade description adequacy. Intrarater agreement showed almost perfect agreement, and the intraclass correlation coefficient of the interrater agreement had a significantly higher agreement rate. The differences between the clinical grades were significant. CONCLUSION: The Hugel Downturned Oral Commissure Scale is precise, reproducible, and reflective of the clinical differences for downturned oral commissure. Its novelty lies in the use of specific angles and ratio. This scale has clinical trial potential owing to its standardized and quantitative assessment.

Volumetric Evaluation of Dead Space in Ischial Pressure Injuries Using Magnetic Resonance Imaging: A Case Series.

OBJECTIVE: To establish a preoperative evaluation procedure by measuring the volume of dead space using MRI in patients with ischial pressure injuries. METHODS: Patients with spinal cord injury and ischial pressure injuries who underwent treatment between August 2016 and November 2019 were included in the study. Preoperative MRI scan was conducted on all patients. The volume estimation and three-dimensional (3D) reconstruction were performed based on MRI data using a 3D Slicer. Based on the resulting volume, a muscle flap that could fit the dead space was selected. Surgery was performed with the selected muscle flap, and a fasciocutaneous flap was added, if necessary. RESULTS: A total of eight patients with ischial pressure injuries were included in the study. The mean patient age was 59.0 ± 11.0 years. The mean body mass index was 26.62 ± 3.89 kg/m2. The mean volume of dead space was 104.75 ± 81.05 cm3. The gracilis muscle was the most selected muscle flap and was used in four patients. In five of eight cases, a fasciocutaneous flap was used as well. The mean follow-up period was 16 months, and by that point, none of the patients evinced complications that required surgery. CONCLUSIONS: To the authors' knowledge, this is the first report on volumetric evaluation of dead space in ischial pressure injuries. The authors believe that the 3D reconstruction process would enable adequate dead space obliteration in ischial pressure injuries. The authors propose that preoperative MRI scans in patients with ischial pressure injury should become an essential part of the process.

In Vitro Screening of a Culturable Soybean Cyst Nematode Cyst Mycobiome for Potential Biological Control Agents and Biopesticides.

Fungal biological control of soybean cyst nematodes (SCN) is an important component of integrated pest management for soybean. However, very few fungal biological control agents are available in the market. In this study, we have screened fungi previously isolated from SCN cysts over 3 years from a long-term crop rotation field experiment for their ability to antagonize SCN using (i) parasitism, (ii) egg hatch inhibition, and (iii) J2 mortality. We evaluated egg parasitism using an in-vitro egg parasitism bioassays and scored parasitism using the egg parasitic index (EPI) and fluorescent microscopy. The ability of these fungi to produce metabolites causing egg hatch inhibition and J2 mortality was assessed in bioassays using filter-sterilized culture filtrates. We identified 10 high-performing isolates each for egg parasitism and toxicity toward SCN eggs and J2s and repeated the tests after storage for 1 year of cryopreservation at -80°C to validate the durability of biocontrol potential of the chosen 20 isolates. Although the parasitic ability changed slightly for the majority of strains after cryopreservation, they still scored 5/10 on EPI scales. There were no differences in the ability of fungi to produce antinemic metabolites after cryopreservation.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.

A Highly Accurate, Polynomial-Based Digital Temperature Compensation for Piezoresistive Pressure Sensor in 180 nm CMOS Technology.

Recently, piezoresistive-type (PRT) pressure sensors have been gaining attention in variety of applications due to their simplicity, low cost, miniature size and ruggedness. The electrical behavior of a pressure sensor is highly dependent on the temperature gradient which seriously degrades its reliability and reduces measurement accuracy. In this paper, polynomial-based adaptive digital temperature compensation is presented for automotive piezoresistive pressure sensor applications. The non-linear temperature dependency of a pressure sensor is accurately compensated for by incorporating opposite characteristics of the pressure sensor as a function of temperature. The compensation polynomial is fully implemented in a digital system and a scaling technique is introduced to enhance its accuracy. The resource sharing technique is adopted for minimizing controller area and power consumption. The negative temperature coefficient (NTC) instead of proportional to absolute temperature (PTAT) or complementary to absolute temperature (CTAT) is used as the temperature-sensing element since it offers the best temperature characteristics for grade 0 ambient temperature operating range according to the automotive electronics council (AEC) test qualification ACE-Q100. The shared structure approach uses an existing analog signal conditioning path, composed of a programmable gain amplifier (PGA) and an analog-to-digital converter (ADC). For improving the accuracy over wide range of temperature, a high-resolution sigma-delta ADC is integrated. The measured temperature compensation accuracy is within ±0.068% with full scale when temperature varies from -40 °C to 150 °C according to ACE-Q100. It takes 37 µs to compute the temperature compensation with a clock frequency of 10 MHz. The proposed technique is integrated in an automotive pressure sensor signal conditioning chip using a 180 nm complementary metal-oxide-semiconductor (CMOS) process.

Development and validation of the COugh Assessment Test (COAT).

BACKGROUND AND OBJECTIVE: A cough-specific quality-of-life questionnaire is recommended to assess the impact of cough; however, a simple instrument to quantify cough is required for everyday clinical practice. This study was aimed to develop a short patient-completed questionnaire (COugh Assessment Test, COAT). METHODS: The COAT was developed and validated by comparison with the Korean version of Leicester Cough Questionnaire (K-LCQ) and cough numeric rating scale (NRS, 0-10, 11-point scale) for chronic cough patients. RESULTS: Item selection identified five items regarding cough frequency, daily activity, sleep disturbance, fatigue and cough hypersensitivity (0-4 scaling of items, 0-20 score range) through reliability test cohort (n = 78). Test-retest reliability was strong (intra-class correlation coefficient = 0.88). The final COAT was compared with K-LCQ and cough NRS in a validation cohort (n = 323). In Rasch analysis, COAT fitted well to a unidimensional model. Pearson correlations of COAT versus K-LCQ (i) before treatment, (ii) after treatment; COAT versus cough NRS (iii) before treatment, (iv) after treatment; (v) delta-COAT versus delta-cough NRS, (vi) delta-COAT versus delta-K-LCQ were (i) -0.71, (ii) -0.81, (iii) 0.69, (iv) 0.82, (v) -0.66 and (vi) 0.72, respectively. CONCLUSION: The COAT is a useful, simple questionnaire for assessing and monitoring cough.

Single-Session versus Multisession Gamma Knife Radiosurgery for Large Brain Metastases from Non-Small Cell Lung Cancer: A Retrospective Analysis.

PURPOSE: To evaluate the efficacy of Gamma Knife radiosurgery (GKS) in patients with large brain metastases by comparing single-session radiosurgery (S-GKS) and multisession radiosurgery (M-GKS), we retrospectively analyzed the clinical outcomes of patients who underwent GKS for brain metastases from non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: Between January 2010 and December 2016, 66 patients with 74 lesions ≥10 cm3 from large brain metastases from only NSCLC were included. Fifty-five patients with 60 lesions were treated with S-GKS; 11 patients with 14 lesions were treated with M-GKS. Median doses were 16 Gy (range, 11-18 Gy) for the S-GKS group and 8 Gy (range, 7-10 Gy) in three fractions for the M-GKS group. RESULTS: With a mean follow-up period of 13.1 months (range, 1.3-76.4 months), the median survival duration was 21.1 months for all patients. Median tumor volume was 14.3 cm3 (range, 10.0-58.3 cm3). The local control rate was 77.0% and the progression-free survival rate was 73.6% at the last follow-up. There were no significant between-group differences in terms of local control rate (p = 0.10). Compared with S-GKS, M-GKS did not differ significantly in radiation-induced complications (38.1 vs. 45.4%, p =0.83). While 8 patients who underwent S-GKS experienced major complications of grade ≥3, no toxicity was observed in patients treated with M-GKS. CONCLUSIONS: M-GKS may be an effective alternative for large brain metastases from NSCLC. Specifically, severe radiation-induced toxicity (≥grade 3) did not occur in M-GKS for large-volume metastases. Although the long-term effects and results from larger samples remain unclear, M-GKS may be a suitable palliative treatment for preserving neurological function.

Frameless Fractionated Gamma Knife Radiosurgery with ICON™ for Large Metastatic Brain Tumors.

BACKGROUND: Recently, a new generation of gamma knife radiosurgery (GKRS) equipped with a frameless immobilization system has encouraged the use of fractionated GKRS as an increasingly favorable treatment option. We investigated the preliminary outcome of efficacy and toxicity associated with frameless fractionated gamma knife radiosurgery (FF GKRS) for the treatment of large metastatic brain tumors. METHODS: Fifteen patients with 17 lesions were treated using FF GKRS and included in this study, because of the large tumor size of more than 10 cm3. FF GKRS was performed based on a thermoplastic mask system for 3 to 5 consecutive days. RESULTS: The mean duration of clinical follow-up was 12 months (range, 4-24), and the local control rate was 100%. Tumor volume decreased in 13 lesions (76.5%), and remained stable in 4 lesions (23.5%). One patient was classified as new lesion development because of the occurrence of leptomeningeal seeding regardless of the tumor volume change. Compared with the initial volume at the time of FF GKRS, tumor volume change at the last follow-up was 62.32% ± 29.80%. Cumulative survival rate at 12 months was 93.3% ± 6.4%. One patient died during the follow-up period because of the progression of the primary disease. No patient showed radiation necrosis on the follow-up images. CONCLUSION: Daily FF GKRS by gamma knife ICON™ revealed satisfactory tumor control rate and low morbidity, despite the short follow-up period. Further prospective studies and a longer follow-up of a large cohort of patients diagnosed with brain metastases are required to elucidate the effect of FF GKRS in brain metastases.

A Fully Integrated Bluetooth Low-Energy Transceiver with Integrated Single Pole Double Throw and Power Management Unit for IoT Sensors.

This paper presents a low power Gaussian Frequency-Shift Keying (GFSK) transceiver (TRX) with high efficiency power management unit and integrated Single-Pole Double-Throw switch for Bluetooth low energy application. Receiver (RX) is implemented with the RF front-end with an inductor-less low-noise transconductance amplifier and 25% duty-cycle current-driven passive mixers, and low-IF baseband analog with a complex Band Pass Filter(BPF). A transmitter (TX) employs an analog phase-locked loop (PLL) with one-point GFSK modulation and class-D digital Power Amplifier (PA) to reduce current consumption. In the analog PLL, low power Voltage Controlled Oscillator (VCO) is designed and the automatic bandwidth calibration is proposed to optimize bandwidth, settling time, and phase noise by adjusting the charge pump current, VCO gain, and resistor and capacitor values of the loop filter. The Analog Digital Converter (ADC) adopts straightforward architecture to reduce current consumption. The DC-DC buck converter operates by automatically selecting an optimum mode among triple modes, Pulse Width Modulation (PWM), Pulse Frequency Modulation (PFM), and retention, depending on load current. The TRX is implemented using 1P6M 55-nm Complementary Metal-Oxide-Semiconductor (CMOS) technology and the die area is 1.79 mm2. TRX consumes 5 mW on RX and 6 mW on the TX when PA is 0-dBm. Measured sensitivity of RX is -95 dBm at 2.44 GHz. Efficiency of the DC-DC buck converter is over 89% when the load current is higher than 2.5 mA in the PWM mode. Quiescent current consumption is 400 nA from a supply voltage of 3 V in the retention mode.

Optimal strategy of gamma knife radiosurgery for craniopharyngiomas.

OBJECT: To analyze the outcomes of gamma knife radiosurgery (GKS) for craniopharyngiomas and elucidate the optimal strategy. METHODS: Between 1998 and 2016, 35 patients underwent GKS for the treatment of 40 recurrent or residual craniopharyngiomas. Among 40 GKSs, 22 procedures were single-session GKSs and 18 procedures were fractionated GKSs. In cases of single-session GKS, the median marginal dose was 15 Gy (range 10-20 Gy). In cases of fractionated GKS, the median marginal dose was 6 Gy (range 5-7.5 Gy) of three fractions. The radiation dose was calculated to the biologic equivalent dose (BED) using α/ß ratios of 10 and 2. RESULT: The location of the tumor, the distance between the optic nerve and tumor (> 10 mm), BED 10 (> 35 Gy), and BED2 (> 80 Gy) were statistically significant with overall response rate (P = 0.008, 0.02, 0.03, and 0.002, respectively). There was a statistically significant difference in progression-free survival according to the distance between the optic nerve and tumor (> 10 mm) and the location of tumor (P = 0.03 and 0.03, respectively). Multivariate logistic regression analysis showed the hypothalamus group had an odds ratio of 0.04 compared with the suprasellar group for tumor progression. The group with BED2 > 80 Gy had an odds ratio of 0.049 compared with the group with BED2 < 80 Gy. CONCLUSION: A sufficient dose is required for treating craniopharyngiomas using single-session and fractionated GKS. The outcomes of GKS can be predicted according to the location of tumor, the distance between the optic nerve and tumor and BED value.

A Retrospective Analysis of the Outcomes of Dural Arteriovenous Fistulas Treated with Gamma Knife Radiosurgery: A Single-Institution Experience.

BACKGROUND: Gamma knife radiosurgery (GKRS) has recently been used as a treatment modality for dural arteriovenous fistula (DAVF). OBJECTIVE: To retrospectively analyze the outcomes of GKRS for DAVF at a single institute. METHODS: Between 1998 and 2016, a total of 20 patients underwent GKRS for DAVF. After excluding 4 patients with > 12 months of follow-up, 16 patients were enrolled in this study. Twelve patients had undergone embolization prior to GKRS. The most common location was the cavernous sinus (CS). The median clinical and radiological follow-up durations were 87.5 (range 24-186) months and 44.5 (range 14-174) months. RESULTS: Ten (62.5%) of the 16 DAVFs were obliterated; 8 were confirmed on angiography. Five cases resulted in small, residual DAVFs, and one case remained unchanged. The obliteration rate of GKRS for CS DAVF was significantly higher than that for non-CS DAVF (100 vs. 40%; p = 0.034). Fifteen out of 16 patients (94%) had a favorable outcome, and the remaining patient had an unfavorable outcome. Hemorrhage after GKRS occurred in only 1 patient, who presented with seizure. CONCLUSIONS: GKRS is a safe and effective treatment modality for DAVF in combination with a traditional treatment option such as endovascular embolization or microsurgery.

A Design of Small Area, 0.95 mW, 612⁻1152 MHz Open Loop Injection-Locked Frequency Multiplier for IoT Sensor Applications.

This paper presents a 612⁻1152 MHz Injection-Locked Frequency Multiplier (ILFM). The proposed ILFM is used to send an input signal to a receiver in only the I/Q mismatch calibration mode. Adopting a Phase-Locked Loop (PLL) to calibrate the receiver places a burden on this system because of the additional area and power consumption that is required. Instead of the PLL, to satisfy high-frequency, low-jitter and low-area requirements, a Ring Oscillator is adopted in the system. The free-running frequency of the ILFM is automatically and digitally calibrated to reflect the frequency of the injected signal from the harmonics of the reference clock. To control the frequency of the ILFM, the load current is digitally tuned with a 6-bit digital control signal. The proposed ILFM locks to the target frequency using a digitally controlled Frequency Locked Loop (FLL). This chip is fabricated using 1-poly 6-metal 0.18 µm CMOS and has achieved the wide tuning range of 612⁻1152 MHz. The power consumption is 0.95 mW from a supply voltage of 1.8 V. The measured phase noise of the ILFM is -108 dBc/Hz at a 1 MHz offset.

Design of a Low-Power, Small-Area AEC-Q100-Compliant SENT Transmitter in Signal Conditioning IC for Automotive Pressure and Temperature Complex Sensors in 180 Nm CMOS Technology.

In this paper, a low-power and small-area Single Edge Nibble Transmission (SENT) transmitter design is proposed for automotive pressure and temperature complex sensor applications. To reduce the cost and size of the hardware, the pressure and temperature information is processed with a single integrated circuit (IC) and transmitted at the same time to the electronic control unit (ECU) through SENT. Due to its digital nature, it is immune to noise, has reduced sensitivity to electromagnetic interference (EMI), and generates low EMI. It requires only one PAD for its connectivity with ECU, and thus reduces the pin requirements, simplifies the connectivity, and minimizes the printed circuit board (PCB) complexity. The design is fully synthesizable, and independent of technology. The finite state machine-based approach is employed for area efficient implementation, and to translate the proposed architecture into hardware. The IC is fabricated in 1P6M 180 nm CMOS process with an area of (116 µm × 116 µm) and 4.314 K gates. The current consumption is 50 µA from a 1.8 V supply with a total 90 µW power. For compliance with AEC-Q100 for automotive reliability, a reverse and over voltage protection circuit is also implemented with human body model (HBM) electro-static discharge (ESD) of +6 kV, reverse voltage of -16 V to 0 V, over voltage of 8.2 V to 16 V, and fabricated area of 330 µm × 680 µm. The extensive testing, measurement, and simulation results prove that the design is fully compliant with SAE J2716 standard.

Ruptured de novo Aneurysm following Gamma Knife Surgery for Arteriovenous Malformation: Case Report.

Stereotactic radiosurgery is a well-known treatment tool for arteriovenous malformations (AVMs). The method has high validity and minimal invasiveness, but late-onset problems involving tumor formation and vasculopathy induced by radiation have been reported. We present a rare case of a radiation-induced ruptured de novo aneurysm following Gamma Knife surgery (GKS) for an AVM. A 17-year-old, right-handed male underwent GKS for AVM at the left parietal lobe. After 3 years, a follow-up angiogram showed a residual AVM at the angular gyrus. Then, a 2nd GKS was performed for the residual lesion. Six years after the 1st GKS, the AVM disappeared on the angiogram. Seven years later, he suffered a sudden onset of headache. A left carotid angiogram revealed a ruptured aneurysm at the M2-M3 junction of the middle cerebral artery parietal branch. Coil embolization was performed, and the aneurysm was occluded. The patient was discharged without any neurologic deficits.

Gamma Knife Radiosurgery for Petroclival Meningioma: Long-Term Outcome and Failure Pattern.

Total removal of petroclival meningioma is difficult, and aggressive extirpation is often associated with significant surgical morbidity and mortality. The aim of this study was to evaluate the long-term outcome and failure pattern of treatment with Gamma Knife radiosurgery (GKRS) in patients with petroclival meningiomas. Eighty-nine consecutive patients with petroclival meningiomas underwent GKRS between 1998 and 2013. Fifty-eight patients received GKRS as a primary treatment and 31 patients underwent GKRS as a secondary treatment after microsurgery. The mean tumor volume was 6.7 cm3 (range, 0.5-46.3 cm3) and the mean marginal dose was 13.2 Gy (range, 8-17 Gy). At the last radiological follow-up, tumor volume was decreased in 50 patients (56.2%), stationary in 34 patients (38.2%), and increased in 5 patients (5.6%). The actuarial progression-free survival after GKRS was 94.7% at 5 years and 88.9% at 10 years. Favorable cranial nerve outcomes were found in 81 patients (91%). A regrowth pattern was present in all 4 patients of the primary treatment group, whereas cyst formation (3 patients) and regrowth (1 patient) were observed in the secondary treatment group. GKRS is an effective and reasonable option as a primary or secondary treatment for petroclival meningioma. Further studies of failure patterns after GKRS for petroclival meningioma are mandatory.

Radiation-induced osteosarcoma after Gamma Knife surgery for vestibular schwannoma: a case report and literature review.

We present a rare case of radiation-induced osteosarcoma following Gamma Knife® surgery (GKS) for a vestibular schwannoma (VS). A 49-year-old female with sporadic VS underwent GKS. Serial follow-up imaging showed that the tumor size decreased. Six years after GKS, magnetic resonance imaging demonstrated regrowth of the tumor. The tumor was removed via the retrosigmoid approach. Interestingly, the final pathology report confirmed osteosarcoma arising in schwannoma with direct transition (osteosarcoma component: 90 %, schwannoma component: 10 %). The osteosarcoma was considered to be a radiation-induced malignancy. The possibility of this rare complication should be explained to the patient before GKS, and the patient should be screened periodically after GKS.