Radiosurgery for Primary Motor and Sensory Cortex Arteriovenous Malformations

Neurosurgery ◽  
2013 ◽  
Vol 73 (5) ◽  
pp. 816-824 ◽  
Author(s):  
Dale Ding ◽  
Chun-Po Yen ◽  
Zhiyuan Xu ◽  
Robert M. Starke ◽  
Jason P. Sheehan
Keyword(s):  
Arteriovenous Malformations ◽  
Cox Regression ◽  
Gamma Knife Radiosurgery ◽  
Intracranial Arteriovenous Malformations ◽  
Cox Regression Analysis ◽  
Factors Associated ◽  
Presenting Symptoms ◽  
Prescription Dose ◽  
Hemorrhage Risk

Abstract BACKGROUND: Eloquent intracranial arteriovenous malformations (AVMs) located in the primary motor or somatosensory cortex (PMSC) carry a high risk of microsurgical morbidity. OBJECTIVE: To evaluate the outcomes of radiosurgery on PMSC AVMs and compare them with radiosurgery outcomes in a matched cohort of noneloquent lobar AVMs. METHODS: Between 1989 and 2009, 134 patients with PMSC AVMs underwent Gamma Knife radiosurgery with a median radiographic and clinical follow-up of 64 and 80 months, respectively. Seizure (40.3%) and hemorrhage (28.4%) were the most common presenting symptoms. Pre-radiosurgery embolization was performed in 33.6% of AVMs. Median AVM volume was 4.1 mL (range, 0.1-22.6 mL), and prescription dose was 20 Gy (range, 7-30 Gy). Cox regression analysis was performed to identify factors associated with obliteration. RESULTS: The overall obliteration rate, including magnetic resonance imaging and angiography, after radiosurgery was 63%. Obliteration was achieved in 80% of AVMs with a volume less than 3 mL compared with 55% for AVMs larger than 3 mL. No previous embolization (P = .002) and a single draining vein (P = .001) were independent predictors of obliteration on multivariate analysis. The annual post-radiosurgery hemorrhage risk was 2.5%. Radiosurgery-related morbidity was temporary and permanent in 14% and 6% of patients, respectively. Comparing PMSC AVMs with matched noneloquent lobar AVMs, the obliteration rates and clinical outcomes after radiosurgery were not statistically different. CONCLUSION: For patients harboring PMSC AVMs, radiosurgery offers a reasonable chance of obliteration with a relatively low complication rate. Eloquent location does not appear to confer the same negative prognostic value for radiosurgery that it does for microsurgery.

Comparison of Hemorrhagic Risk in Intracranial Arteriovenous Malformations Between Conservative Management and Embolization as the Single Treatment Modality

Neurosurgery ◽  
2017 ◽  
Vol 82 (4) ◽  
pp. 481-490 ◽  
Author(s):  
Wuyang Yang ◽  
Jose L Porras ◽  
Risheng Xu ◽  
Maria Braileanu ◽  
Syed Khalid ◽  
...  
Keyword(s):  
Conservative Management ◽  
Arteriovenous Malformations ◽  
Cox Regression ◽  
Older Age ◽  
Treatment Modalities ◽  
Intracranial Arteriovenous Malformations ◽  
Cox Regression Analysis ◽  
Increased Risk ◽  
Hemorrhagic Risk

Abstract BACKGROUND Embolization has been discussed as a feasible single modality treatment for intracranial arteriovenous malformations (AVMs). OBJECTIVE To compare hemorrhagic risk between embolization and conservative management in a multivariate survival analysis. METHODS We retrospectively reviewed records of patients with intracranial AVMs evaluated at our institution from 1990 to 2013. We included patients recommended to undergo embolization without other treatment modalities and patients managed conservatively. Multivariate Cox regression analysis of hemorrhage-free survival was performed, with the survival interval right-censored to date of either last follow-up or salvage treatment. RESULTS We identified 205 patients matching our inclusion criteria, with 160 patients in the noninterventional group and 45 in the embolization group. The average age of all patients was 40.2 ± 19.5 yr, with younger patients undergoing embolization more often (P = .026). Fifty-one (31.9%) conservatively managed patients and 13 (28.9%) patients treated by embolization (P = .703) presented with hemorrhage. Other baseline characteristics were similar between the 2 management groups. During an average follow-up period of 7.7 yr, 30 patients (14.6%) experienced hemorrhage recurrence. Multivariate Cox regression revealed older age (P = .031) and hemorrhagic presentation (P < .001) to be statistically associated with follow-up hemorrhage. In a subset analysis of unruptured AVMs, embolization was associated with a 4-fold hazard ratio of hemorrhage compared to conservative management (P = .044). CONCLUSION Older age and initial presentation with hemorrhage were associated with increased risk of hemorrhage during follow-up. Treatment of AVMs with embolization as the sole modality may increase hemorrhagic risk compared with conservative management, especially in unruptured AVMs.

Factors related to complete occlusion of arteriovenous malformations after gamma knife radiosurgery

2000 ◽  
Vol 93 (supplement_3) ◽  
pp. 96-101 ◽  
Author(s):  
Jong Hee Chang ◽  
Jin Woo Chang ◽  
Yong Gou Park ◽  
Sang Sup Chung
Keyword(s):  
Gamma Knife ◽  
Arteriovenous Malformations ◽  
Gamma Knife Radiosurgery ◽  
Maximum Diameter ◽  
Content Type ◽  
Complete Occlusion ◽  
Factors Associated ◽  
Martin Grade ◽  
Fine Print

Object. The authors sought to evaluate the effects of gamma knife radiosurgery (GKS) on cerebral arteriovenous malformations (AVMs) and the factors associated with complete occlusion. Methods. A total of 301 radiosurgical procedures for 277 cerebral AVMs were performed between December 1988 and December 1999. Two hundred seventy-eight lesions in 254 patients who were treated with GKS from May 1992 to December 1999 were analyzed. Several clinical and radiological parameters were evaluated. Conclusions. The total obliteration rate for the cases with an adequate radiological follow up of more than 2 years was 78.9%. In multivariate analysis, maximum diameter, angiographically delineated shape of the AVM nidus, and the number of draining veins significantly influenced the result of radiosurgery. In addition, margin radiation dose, Spetzler—Martin grade, and the flow pattern of the AVM nidus also had some influence on the outcome. In addition to the size, topography, and radiosurgical parameters of AVMs, it would seem to be necessary to consider the angioarchitectural and hemodynamic aspects to select proper candidates for radiosurgery.

scholarly journals FRI0248 PROGNOSTIC FACTORS FOR STEROID-FREE REMISSION IN PATIENTS WITH IDIOPATHIC INFLAMMATORY MYOPATHIES: IMPORTANCE OF ANTHROPOMETRIC MEASUREMENTS

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 708.1-708
Author(s):  
J. S. Lee ◽  
S. H. Nam ◽  
S. J. Choi ◽  
W. J. Seo ◽  
S. Hong ◽  
...  
Keyword(s):  
Prognostic Factors ◽  
Cox Regression ◽  
Idiopathic Inflammatory Myopathies ◽  
Inflammatory Myopathies ◽  
Immunosuppressant Therapy ◽  
Muscle Enzymes ◽  
Cox Regression Analysis ◽  
Factors Associated ◽  
Early Use

Background:Several studies have been conducted on factors associated with mortality in idiopathic inflammatory myopathies (IIM), but few studies have assessed prognostic factors for steroid-free remission in IIM.Objectives:We investigated the various clinical factors, including body measurements, that affect IIM treatment outcomes.Methods:Patients who were newly diagnosed with IIM between 2000 and 2018 were included. Steroid-free remission was defined as at least three months of normalisation of muscle enzymes and no detectable clinical disease activity. The factors associated with steroid-free remission were evaluated by a Cox regression analysis.Results:Of the 106 IIM patients, 35 displayed steroid-free remission during follow-up periods. In the multivariable Cox regression analyses, immunosuppressants’ early use within one month after diagnosis [hazard ratio (HR) 6.21, 95% confidence interval (CI) 2.61–14.74, p < 0.001] and sex-specific height quartiles (second and third quartiles versus first quartile, HR 3.65, 95% CI 1.40–9.51, p = 0.008 and HR 2.88, 95% CI 1.13–7.32, p = 0.027, respectively) were positively associated with steroid-free remission. Polymyositis versus dermatomyositis (HR 0.21, 95% CI 0.09–0.53, p = 0.001), presence of dysphagia (HR 0.15, CI 0.05–0.50, p = 0.002) and highest versus lowest quartile of waist circumference (WC) (HR 0.24, 95% CI 0.07–0.85, p = 0.027) were negatively associated with steroid-free remission.Conclusion:The early initiation of immunosuppressant therapy, type of myositis and presence of dysphagia are strong predictors of steroid-free remission in IIM; moreover, height and WC measurements at baseline may provide additional important prognostic value.Disclosure of Interests:None declared

scholarly journals P03.08 Large cerebral arteriovenous malformations management with Volume-staged gamma knife radiosurgery

2019 ◽  
Vol 21 (Supplement_3) ◽  
pp. iii26-iii26
Author(s):  
R M Emad Eldin ◽  
W A Reda ◽  
A M El-Shehaby ◽  
K Abdel Karim ◽  
A Nabeel ◽  
...  
Keyword(s):  
Gamma Knife ◽  
Arteriovenous Malformations ◽  
Gamma Knife Radiosurgery ◽  
Cerebral Arteriovenous Malformations ◽  
Factors Affecting ◽  
Prescription Dose ◽  
The Mean ◽  
Cerebral Avms ◽  
Grade 3

Abstract BACKGROUND Large cerebral arteriovenous malformations (AVM) pose a management dilemma because of the limited success of any single treatment modality by itself. Surgery alone is associated with significant morbidity and mortality. Similarly, embolization alone has limited efficacy. Volume-staged gamma knife radiosurgery (VSGR) has been developed for the treatment of large AVMs, to increase the efficacy and improve safety of treatment of these lesions. The aim of the study was to assess the efficacy and safety of VSGR technique for the treatment of large cerebral AVMs. METHODS The study included patients treated by VSGR between May 2009 and July 2015. All cases had large AVMs (>10 cc). These were 29 patients. RESULTS Twenty-four patients completed radiographic follow up with 15 obliteration cases (62.5%). There was a total of 56 sessions performed. The mean AVM volume was 16 cc (10.1–29.3 cc). The mean prescription dose was 18 Gy (14–22 Gy). The mean follow up duration was 43 months (21–73 months). One patient died during follow up from unrelated cause. Two cases suffered haemorrhage during follow up. Symptomatic edema developed in 5 (17%) patients. The factors affecting obliteration were smaller total volume, higher dose/stage, non-deep location, compact AVM, AVM score less than 3, >18 Gy dose and <15 cc total volume. The factors affecting symptomatic edema were smaller total volume and shorter time between first and last sessions (p 0.012). T2 image changes were affected by SM grade 3 or more (p 0.013) and AVM score 3 or more (p 0.014). CONCLUSION VSGR provides an effective and safe treatment option for large cerebral AVMs. Smaller AVM volume is associated with higher obliteration rate.

Radiosurgery for patients with unruptured intracranial arteriovenous malformations

2013 ◽  
Vol 118 (5) ◽  
pp. 958-966 ◽  
Author(s):  
Dale Ding ◽  
Chun-Po Yen ◽  
Zhiyuan Xu ◽  
Robert M. Starke ◽  
Jason P. Sheehan
Keyword(s):  
Arteriovenous Malformations ◽  
Cox Regression ◽  
Univariate Analysis ◽  
Cyst Formation ◽  
Intracranial Arteriovenous Malformations ◽  
Radiation Induced ◽  
Prescription Dose ◽  
Martin Grade ◽  
The Mean ◽  
Induced Changes

Object The appropriate management of unruptured intracranial arteriovenous malformations (AVMs) remains controversial. In the present study, the authors evaluate the radiographic and clinical outcomes of radiosurgery for a large cohort of patients with unruptured AVMs. Methods From a prospective database of 1204 cases of AVMs involving patients treated with radiosurgery at their institution, the authors identified 444 patients without evidence of rupture prior to radiosurgery. The patients' mean age was 36.9 years, and 50% were male. The mean AVM nidus volume was 4.2 cm3, 13.5% of the AVMs were in a deep location, and 44.4% were at least Spetzler-Martin Grade III. The median radiosurgical prescription dose was 20 Gy. Univariate and multivariate Cox regression analyses were used to determine risk factors associated with obliteration, postradiosurgery hemorrhage, radiation-induced changes, and postradiosurgery cyst formation. The mean duration of radiological and clinical follow-up was 76 months and 86 months, respectively. Results The cumulative AVM obliteration rate was 62%, and the postradiosurgery annual hemorrhage rate was 1.6%. Radiation-induced changes were symptomatic in 13.7% and permanent in 2.0% of patients. The statistically significant independent positive predictors of obliteration were no preradiosurgery embolization (p < 0.001), increased prescription dose (p < 0.001), single draining vein (p < 0.001), radiological presence of radiation-induced changes (p = 0.004), and lower Spetzler-Martin grade (p = 0.016). Increased volume and higher Pittsburgh radiosurgery-based AVM score were predictors of postradiosurgery hemorrhage in the univariate analysis only. Clinical deterioration occurred in 30 patients (6.8%), more commonly in patients with postradiosurgery hemorrhage (p = 0.018). Conclusions Radiosurgery afforded a reasonable chance of obliteration of unruptured AVMs with relatively low rates of clinical and radiological complications.

Analysis of the causes of treatment failure in gamma knife radiosurgery for intracranial arteriovenous malformations

2000 ◽  
Vol 93 (supplement_3) ◽  
pp. 104-106 ◽  
Author(s):  
Yang Kwon ◽  
Sang Ryong Jeon ◽  
Jeong Hoon Kim ◽  
Jung Kyo Lee ◽  
Dong Sook Ra ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Treatment Failure ◽  
Gamma Knife ◽  
Arteriovenous Malformations ◽  
Gamma Knife Radiosurgery ◽  
Intracranial Arteriovenous Malformations ◽  
Content Type ◽  
The Mean ◽  
Fine Print

Object. The authors sought to analyze causes for treatment failure following gamma knife radiosurgery (GKS) for intracranial arteriovenous malformations (AVMs), in cases in which the nidus could still be observed on angiography 3 years postsurgery. Methods. Four hundred fifteen patients with AVMs were treated with GKS between April 1990 and March 2000. The mean margin dose was 23.6 Gy (range 10–25 Gy), and the mean nidus volume was 5.3 cm3 (range 0.4–41.7 cm3). The KULA treatment planning system and conventional subtraction angiography were used in treatment planning. One hundred twenty-three of these 415 patients underwent follow-up angiography after GKS. After 3 years the nidus was totally obliterated in 98 patients (80%) and partial obliteration was noted in the remaining 25. There were several reasons why complete obliteration was not achieved in all cases: inadequate nidus definition in four patients, changes in the size and location of the nidus in five patients due to recanalization after embolization or reexpansion after hematoma reabsorption, a large AVM volume in five patients, a suboptimal radiation dose to the thalamic and basal ganglia in eight patients, and radioresistance in three patients with an intranidal fistula. Conclusions. The causes of failed GKS for treatment of AVMs seen on 3-year follow-up angiograms include inadequate nidus definition, large nidus volume, suboptimal radiation dose, recanalization/reexpansion, and radioresistance associated with an intranidal fistula.

Repeat Radiosurgery for Intracranial Arteriovenous Malformations

Neurosurgery ◽  
2011 ◽  
Vol 70 (1) ◽  
pp. 150-154 ◽  
Author(s):  
John M. Stahl ◽  
Yueh-Yun Chi ◽  
William A. Friedman
Keyword(s):  
Initial Treatment ◽  
Arteriovenous Malformations ◽  
Intracranial Arteriovenous Malformations ◽  
University Of Florida ◽  
The Status ◽  
Median Volume ◽  
Radiation Induced ◽  
Prescription Dose ◽  
The University

Abstract BACKGROUND Despite a high success rate in the stereotactic radiosurgical treatment of intracranial arteriovenous malformations (AVMs) that cannot be safely resected with microsurgery, some patients must be managed after treatment failure. OBJECTIVE To provide an update on the use of repeat linear accelerator radiosurgery as a treatment for failed AVM radiosurgery at the University of Florida. METHODS We reviewed 103 patients who underwent repeat radiosurgical treatment for residual AVM at the University of Florida between December 1991 and December 2007. Each of these patients had at least 2 radiosurgical treatments for the same AVM. Patient information, including AVM nidus volume, prescription dose, age, and sex, was collected at the time of initial treatment and again at the time of retreatment. Patients were followed up after treatment with magnetic resonance, computed tomography, and angiographic imaging at standard intervals to determine the status of their AVM. The median follow-up after retreatment was 31 months. RESULTS Between the first and second treatments, the median AVM nidus volume was decreased by 69% (from a median volume of 12.7 to 4.0 cm3), allowing the median prescribed dose to be increased from 1500 cGy on initial treatment to 1750 cGy on retreatment. The final obliteration rate on retreatment was 65.3%. After salvage retreatment, 5 patients (4.9%) experienced radiation-induced complications, and 6 patients (5.8%) experienced posttreatment hemorrhage. CONCLUSION Repeat radiosurgery is a safe and effective salvage treatment for AVMs.

scholarly journals Five-year follow-up of active surveillance for prostate cancer: A Canadian community-based urological experience

2014 ◽  
Vol 8 (11-12) ◽  
pp. 768 ◽  
Author(s):  
J. Matthew J. Andrews ◽  
James E. Ashfield ◽  
Michael Morse ◽  
Thomas F. Whelan
Keyword(s):  
Prostate Cancer ◽  
Median Time ◽  
Active Surveillance ◽  
Cox Regression ◽  
Specific Antigen ◽  
Cox Regression Analysis ◽  
Factors Associated ◽  
Psa Density ◽  
Prostate Biopsies

Introduction: We assessed oncological outcomes of active surveillance (AS) using a community database and identified factors associated with disease reclassification on surveillance biopsy.Methods: A retrospective review was performed on 200 men on AS. Prostate-specific antigen (PSA) was measured every 3 to 6 months. Prostate biopsies were performed every 1 to 4 years, and at the individual physician’s discretion. Disease reclassification was defined as clinical T1 to cT2 progression, or histologically as >2 cores positive, Gleason score >6, or >50% core involvement on surveillance biopsy. Multivariate Cox regression analysis evaluated factors associated with disease reclassification. Kaplan-Meier survival curves were plotted.Results: We assessed a heterogeneous cohort of 86 patients, with a median age 67.2 years, who received ≥1 surveillance biopsies. The median follow-up was 5.2 years. The median times to first and second surveillance biopsies were 730 and 763 days, respectively. Overall, 47% of patients were reclassified on surveillance biopsy after a median 2.1 years. Factors associated with disease reclassification were PSA density >0.20 (p < 0.0001, hazard ratio [HR] 4.55, 95% confidence interval [CI] 2.116–9.782) and ≥3 positive cores (p = 0.0152, HR 3.956, 95% CI 1.304–12.003) at diagnosis, and number of positive cores on surveillance biopsy. In total, 25 (29%) patients received delayed intervention, with a median time to intervention of 2.6 years. The median time on AS was 4.4 years, with an overall survival of 95% and prostate-specific survival of 100%.Conclusions: Our community study supports AS to reduce over treatmentof prostate cancer. PSA density >0.20 and ≥3 cores positive are associated with disease reclassification on surveillance biopsy.

Radiosurgery for Spetzler-Martin Grade III arteriovenous malformations

2014 ◽  
Vol 120 (4) ◽  
pp. 959-969 ◽  
Author(s):  
Dale Ding ◽  
Chun-Po Yen ◽  
Robert M. Starke ◽  
Zhiyuan Xu ◽  
Xingwen Sun ◽  
...  
Keyword(s):  
Arteriovenous Malformations ◽  
Latency Period ◽  
Cox Proportional Hazards ◽  
Favorable Outcome ◽  
Obliteration Rate ◽  
Presenting Symptoms ◽  
Prescription Dose ◽  
Martin Grade ◽  
Grade Iii

Object Intracranial arteriovenous malformations (AVMs) are most commonly classified based on their Spetzler-Martin grades. Due to the composition of the Spetzler-Martin grading scale, Grade III AVMs are the most heterogeneous, comprising 4 distinct lesion subtypes. The management of this class of AVMs and the optimal treatment approach when intervention is indicated remain controversial. The authors report their experience with radiosurgery for the treatment of Grade III AVMs in a large cohort of patients. Methods All patients with Spetzler-Martin Grade III AVMs treated with radiosurgery at the University of Virginia over the 20-year span from 1989 to 2009 were identified. Patients who had less than 2 years of radiological follow-up and did not have evidence of complete obliteration during that period were excluded from the study, leaving 398 cases for analysis. The median patient age at treatment was 31 years. The most common presenting symptoms were hemorrhage (59%), seizure (20%), and headache (10%). The median AVM volume was 2.8 cm3, and the median prescription dose was 20 Gy. The median radiological and clinical follow-up intervals were 54 and 68 months, respectively. Univariate and multivariate Cox proportional hazards and logistic regression analysis were used to identify factors associated with obliteration, postradiosurgery radiation-induced changes (RIC), and favorable outcome. Results Complete AVM obliteration was observed in 69% of Grade III AVM cases at a median time of 46 months after radiosurgery. The actuarial obliteration rates at 3 and 5 years were 38% and 60%, respectively. The obliteration rate was higher in ruptured AVMs than in unruptured ones (p < 0.001). Additionally, the obliteration rate for Grade III AVMs with small size (< 3 cm diameter), deep venous drainage, and location in eloquent cortex was higher than for the other subtypes (p < 0.001). Preradiosurgery AVM rupture (p = 0.016), no preradiosurgery embolization (p = 0.003), increased prescription dose (p < 0.001), fewer isocenters (p = 0.006), and a single draining vein (p = 0.018) were independent predictors of obliteration. The annual risk of postradiosurgery hemorrhage during the latency period was 1.7%. Two patients (0.5%) died of hemorrhage during the radiosurgical latency period. The rates of symptomatic and permanent RIC were 12% and 4%, respectively. Absence of preradiosurgery AVM rupture (p < 0.001) and presence of a single draining vein (p < 0.001) were independent predictors of RIC. Favorable outcome was observed in 63% of patients. Independent predictors of favorable outcome were no preradiosurgery hemorrhage (p = 0.014), increased prescription dose (p < 0.001), fewer isocenters (p = 0.014), deep location (p = 0.014), single draining vein (p = 0.001), and lower Virginia radiosurgery AVM scale score (p = 0.016). Conclusions Radiosurgery for Spetzler-Martin Grade III AVMs yields relatively high rates of obliteration with a low rate of adverse procedural events. Small and ruptured lesions are more likely to become obliterated after radiosurgery than large and unruptured ones.

scholarly journals Factors affecting the healing of the perineum following surgery

2013 ◽  
Vol 95 (4) ◽  
pp. 252-257 ◽  
Author(s):  
B Ip ◽  
M Jones ◽  
P Bassett ◽  
R Phillips
Keyword(s):  
Odds Ratio ◽  
Cox Regression ◽  
Multivariate Analyses ◽  
Causative Factor ◽  
Ileoanal Pouch ◽  
Factors Affecting ◽  
Cox Regression Analysis ◽  
Factors Associated ◽  
Inflammatory Bowel

Introduction The aim of this study was to establish patient and procedural factors associated with the development of an unhealed perineum in patients undergoing a proctectomy or excision of an ileoanal pouch. Methods A review of 194 case notes for procedures performed between 1997 and 2009 was carried out. All patients had at least 12 months’ follow-up. Univariate and multivariate analyses were performed in 16 parameters. For those patients who developed an unhealed perineum, Cox regression analysis was performed to establish healing over a 12-month period. Results Two hundred patients were included in the study, of which six had unknown wound status and were subsequently excluded. This left 194 study patients. Of these, 86 (44%) achieved primary wound healing with a fully healed perineum and 108 (56%) experienced primary wound failure. With reference to the latter, 63 (58%) healed by 12 months. Comparing patients with an initially intact perineum with those with initial wound failure showed pre-existing sepsis was highly relevant (odds ratio: 4.32, 95% confidence interval [CI]: 2.16–8.62, p<0.001). In patients who had an unhealed perineum initially, perineal sepsis and surgical treatment were both significantly associated with time to healing (hazard ratio [HR]: 0.54, 95% CI: 0.31–0.93, p=0.03; and HR: 0.42, 95% CI: 0.21–0.84, p=0.01). Conclusions The presence of pre-existing perineal sepsis is associated with an unhealed perineum following proctectomy in inflammatory bowel disease (IBD) and non-IBD surgery. Further studies are indicated to establish perineal sepsis as a causative factor.

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