Direct visual internal urethrotomy for isolated, post-urethroplasty strictures: a retrospective analysis

PubMed Central

Brown, Elizabeth Timbrook; Mock, Stephen; Dmochowski, Roger; Reynolds, W. Stuart; Milam, Douglas; Kaufman, Melissa R.

2016-01-01

Background: Urethroplasty is often successful for the treatment of male urethral stricture disease, but limited data exists on recurrence management. Our goal was to evaluate direct visual internal urethrotomy (DVIU) as a treatment option for isolated, recurrent strictures after urethroplasty. Methods: We retrospectively identified male patients who underwent urethroplasty from 1999 to 2013 and developed an isolated, recurrent stricture at the urethroplasty site treated with DVIU. Success was defined as lack of symptomatology and no subsequent intervention. Comparative analysis identified characteristics and stricture properties associated with success. Results: A total of 436 urethroplasties were performed in 401 patients at our institution between 1999 and 2013. Stricture recurrence was noted in 64 (16%) patients. Of these, 47 (73%) underwent a DVIU. A total of 37 patients met inclusion criteria and underwent 50 DVIU procedures at the urethroplasty site. A single DVIU was successful in 13 of 37 patients (35%). A total of 4 of 6 patients required a second DVIU (67%). Overall, 17 of 43 (40%) of the total DVIUs were successful after urethroplasty. Success did not differ by age, stricture length or location, surgical technique, radiation history, prior urethroplasty or DVIU, time to failure, or etiology. Conclusions: Post-urethroplasty DVIU for isolated, recurrent strictures may be offered as a minimally invasive treatment option. Approximately 40% of patients were spared further intervention. PMID:28203286

Optical urethrotomy under local anaesthesia is a feasible option in urethral stricture disease.

PubMed

Munks, D G; Alli, M O; Goad, E H Abdel

2010-01-01

The aim of our study was to assess the feasibility of performing optical urethrotomy for urethral stricture disease under local anaesthesia. A total of 33 patients with radiologically proven urethral stricture underwent optical urethrotomy by a single operator under local anaesthesia. Of these patients, 23 (70%) had stricture involving the corpora spongiosum and 18 (55%) of the patients were dependent on supra-pubic catheters. The procedure was successful in 30 cases (91%). The procedure was very well tolerated (average visual analogue pain score of 2/10) with an extremely low complication rate. The large number of patients with urethral stricture disease and the premium on operating time on formal theatre slates encouraged us to perform these procedures under local anaesthetic. Although most patients had severe stricture disease, the majority of cases were successful and very well tolerated. Optical urethrotomy under local anesthesia could be a viable option in the absence of formal theatre time and the facilities to perform general anaesthesia.

Long-term effect of urethral dilatation and internal urethrotomy for urethral strictures.

PubMed

Veeratterapillay, Rajan; Pickard, Rob S

2012-11-01

Urethral dilatation and direct visual internal urethrotomy (DVIU) are widely used minimally invasive options to manage men with urethral strictures. Advances in open urethroplasty with better long-term cure rates have fuelled the continuing debate as to which treatment is best for primary and recurrent urethral strictures. We reviewed recent literature to identify contemporary practice of urethral dilatation and DVIU and the long-term outcome of these procedures. Systematic literature search for the period January 2010 to December 2011 showed that urethral dilatation and DVIU remain frequently used treatment options as confirmed by surveys of urologists in the USA and the Netherlands. Multiple reports of laser DVIU confirm the safety of this approach but long-term data were lacking. Stricture free rates from urethra dilatation and DVIU vary from 10 to 90% at 12 months, although adjunctive intermittent self-dilatation can reduce time to recurrence. Although quality-of-life benefit appears good in the short term, repeated procedures may harm sexual function in the long-term. Urethral dilatation and DVIU remain widely used in urethral stricture management but high-level comparative evidence of benefit and harms against urethroplasty in the short and long-term is still lacking.

Thulium laser urethrotomy for urethral stricture: a preliminary report.

PubMed

Wang, Linhui; Wang, Zhixiang; Yang, Bo; Yang, Qing; Sun, Yinghao

2010-09-01

The outcome of thulium laser urethrotomy for patients with urethral stricture had not been reported. The purpose of this study was to evaluate outcome of endourethrotomy with the thulium laser as a minimally invasive treatment for urethral stricture. Twenty-one consecutive patients with urethral stricture were evaluated by retrograde uroflowmetry, International Prostate Symptom Score (IPSS), and quality of life preoperatively at a single academic center. All patients were treated with thulium laser urethrotomy. All patients were followed up for 12-24 months postoperatively by uroflowmetry and by retrograde with voiding cystourethrogram every 3 months. And all patients were followed up by mailed questionnaire, including IPSS and quality of life. Retrograde endoscopic thulium laser urethrotomy was performed in all 21 patients. Most patients (N = 16; 76.2%) did not need any reintervention. Five patients developed recurrent strictures, of them two patients were treated by another laser urethrotomy, one patient was treated by open urethroplasty with buccal mucosa and the other two patients' reintervention were treated by urethral dilation. No intraoperative complications were encountered, although in 9.5% (N = 2) of patients, a urinary tract infection was diagnosed postoperatively. No gross hematuria occurred. Including two patients treated with repeat laser urethrotomy, 17(81.0%) showed good flow of urine (Q(ave)>16.0 ml/second) and adequate caliber urethra in retrograde urethrogram (RGU) 12 months after operation. Three (14.3%) patients showed narrow stream of urine (Q(ave)<8.0 ml/second) and urethral dilation was done every month or 2 months. There was one patient whose Q(ave) was between 8.0 and 16.0 ml/second. And this patient was treated by neither urethral dilation nor another laser urethrotomy. The thulium laser urethrotomy was a safe and effective minimally invasive therapeutic modality for urethral stricture. 2010 Wiley-Liss, Inc.

Double Intracavernous Breakage of Sachse's Knife Blade: Management of a Rare Complication Performing Direct Vision Internal Urethrotomy.

PubMed

Benincasa, Alfonso; Saita, Alberto; Pinto, Angelo; Pilerci, Carmine; Francesco, Lamberti; Russo, Aniello; Benincasa, Giuseppe

2017-01-01

Background: Although the breakage of a Sachse's knife blade is already a rare event while performing optical internal urethrotomy, a double failure appears to be at the same time a unique and a challenging complication to manage since no reference has emerged from literature review. Case Presentation: A male patient, 80 years of age, underwent retreatment of recurrent urethral stricture that occurred after transurethral resection of the prostate. The latter was complicated by severe intraoperative urethrorrhagia; this is the reason he was transferred from another institution where at first a suprapubic cystostomy was carried out, followed by urethral recanalization through internal urethrotomy and finally he underwent intracavernous Sachse's knife blade discharge. Preoperative evaluation included combined retrograde and voiding urethrography and CT to evaluate the complete resolution of the urethral stenosis and to establish the correct location of the blades inside the corpus cavernosum. A transperineal approach to the left corpus cavernosum was carried out with manageable removal of the foreign body and postoperative assessment showed no early considerable complications for the patient. Conclusion: To our knowledge, this is the first case of double breakage of Sachse's knife blade performing optical internal urethrotomy reported in literature. Although it may appear to be an easy procedure, close attention to its execution must always be paid to prevent major complications. A transperineal approach has proven to be effective and safe without creating any further outcomes to the patient.

Safety and efficacy of Intraurethral Mitomycin C Hydrogel for prevention of post-traumatic anterior urethral stricture recurrence after internal urethrotomy.

PubMed

Moradi, Mahmoudreza; Derakhshandeh, Katayoun; Karimian, Babak; Fasihi, Mahtab

2016-07-01

Evaluation of the safety and efficacy of intraurethral Mitomycin C (MMC) hydrogel for prevention of post-traumatic anterior urethral stricture recurrence after internal urethrotomy. A thermoresponsive hydrogel base consisting of 0.8 mg MMC with 1cc water and propylene glycol to PF-127 poloxamer was used in theater. 40 male patients with short, non-obliterated, urethral stricture were randomized into 2 groups: control and MMC. After internal urethrotomy, the MMC group patients received the MMC-Hydrogel while the others were just catheterized. Both groups had their catheters for at least 1 week. After surgery, they were followed up by means of medical history and physical examination, monitoring voiding patterns and retrograde urethrogram at 1 month, 6 months and 1 year after surgery. 40 male patients between 14 to 89 years old (Mean = 54.15) underwent internal urethrotomy. The average age for the control and MMC group was 54.55±21.25 and 53.75±24.75 respectively. In a comparison of age between the two groups, they were matched (P=0.574). Stricture length was 10.7±5.9 and 9.55±4.15 mm for the control and MMC group respectively. There were no statistically meaningful differences between the two groups (P=0.485). Fifteen patients had a history of one previous internal urethrotomy which in a comparison between the two groups meant there was no meaningful difference (P=0.327). During postoperative follow up, total urethral stricture recurrence happened in 12 patients: 10 patients (50%) in control group and 2 patients (10%) in MMC group. The difference was statistically significant (P=0.001). There were no significant complications associated with the MMC injection in our patients. Based on our results, MMC Hydrogel may have an anti-fibrotic action preventing post-traumatic anterior urethral stricture recurrence with no side effects on pre-urethral tissue. Due to our study limitations, our follow up time and the small number of patients, our results were not conclusive and further studies will be needed with a longer follow up time. © 2016 KUMS, All rights reserved.

Low-power holmium:YAG laser urethrotomy for treatment of urethral strictures: functional outcome and quality of life.

PubMed

Kamp, Stefan; Knoll, Thomas; Osman, Mahmoud M; Köhrmann, Kai Uwe; Michel, Maurice S; Alken, Peter

2006-01-01

To evaluate the efficacy of endourethrotomy with the holmium:YAG laser as a minimally invasive treatment for urethral stricture. Between January 2002 and January 2004, 32 male patients with symptomatic urethral strictures (8 bulbar, 9 penile, 9 combined) were treated with Ho:YAG-laser urethrotomy in our department. The stricture was iatrogenic in 60% (N = 18), inflammatory in 16.6% (N = 5), traumatic in 13.3% (N = 4), and idiopathic in 7% (N = 3). The stricture was incised under vision at the 12 o'clock location or the site of maximum scar tissue or narrowing in asymmetric strictures. Laser energy was set on 1200 to 1400 mJ with a frequency of 10 to 13 Hz. Postoperatively, drainage of the bladder was performed for 4 days using a 18F silicone catheter. Triamcinolone was instilled intraurethrally after removal of the catheter in all patients. Patients were followed up by mailed questionnaire, including International Prostate Symptom Score and quality of life. Retrograde endoscopic Ho:YAG laser urethrotomy could be performed in all 32 patients. Most patients (22; 68.7%) did not need any reintervention. Ten patients developed recurrent strictures that were treated by another laser urethrotomy in 4 patients (12.5%), while 6 patients (18.7%) needed open urethroplasty with buccal mucosa. Including 2 patients treated with repeat laser urethrotomy, 24 patients (75%) were considered successful after a mean follow-up of 27 months (range 13-38 months). No intraoperative complications were encountered, although in 5% of patients, a urinary-tract infection was diagnosed postoperatively. No gross hematuria occurred. The Ho:YAG laser urethrotomy is a safe and effective minimally invasive therapeutic modality for urethral stricture with results comparable to those of conventional urethrotomy. Further data from long-time follow-up are necessary to compare the success rate with that of conventional urethrotomy and urethroplasty. Nevertheless, the Ho:YAG laser urethrotomy might at least be an alternative to urethroplasty in patients with high comorbidity who are not suitable for open reconstruction.

Unsuccessful outcomes after posterior urethroplasty: definition, diagnosis, and treatment.

PubMed

Koraitim, Mamdouh M

2012-05-01

To establish some guidelines for the definition, diagnosis, and treatment of failed posterior urethroplasty. We identified 20 successive patients who required a secondary endoscopic or surgical procedure after anastomotic repair of a postpelvic fracture urethral injury from 1979 to 2010. Of the 20 patients, 18 had undergone perineal repair and 2 a perineo-abdominal procedure. Their medical records were reviewed with a focus on 6 postoperative items: symptoms, onset of unsuccessful result, urethral calibration, urethrocystography, urethroscopy, and treatment. Follow-up ranged from 1 to 25 years (mean 14). Of the 20 patients, 11 (55%) presented shortly after removal of the urethral stent with failure to void (n = 9) or incontinence (n = 2), and 9 (45%) presented 1 month to 12 years after surgery with a weak stream. Early failures resulted from obstruction at the site of repair in 5 patients, retraction of the bulbar urethra in 3, wrong anastomosis to a false tract in 1, and an open bladder neck in 2. Correction was accomplished by salvage urethroplasty in 8 patients and bladder neck repair in 2. Late failures resulted from narrowing of the anastomosis and were corrected by direct visual internal urethrotomy in 7 patients and surgery in 2. Unsuccessful outcomes can be encountered shortly after removal of the urethral stent or delayed for several months or years after surgery. Early cases present by an inability to void or incontinence and usually require salvage urethroplasty or bladder neck repair. Late cases present by a weak urinary stream, are due to narrowing of the anastomosis, and are usually corrected by direct visual internal urethrotomy. Copyright © 2012 Elsevier Inc. All rights reserved.

Visual Internal Urethrotomy With Intralesional Mitomycin C and Short-term Clean Intermittent Catheterization for the Management of Recurrent Urethral Strictures and Bladder Neck Contractures.

PubMed

Farrell, Michael R; Sherer, Benjamin A; Levine, Laurence A

2015-06-01

To evaluate our longitudinal experience using visual internal urethrotomy (VIU) with intralesional mitomycin C (MMC) and short-term clean intermittent catheterization (CIC) for urethral strictures and bladder neck contractures (BNC) after failure of endoscopic management. This case series involved review of our prospectively developed database of all men who underwent VIU with MMC and CIC in a standardized fashion for urethral stricture or BNC between 2010 and 2013 at our tertiary care medical center. Etiology was identified as radiation-induced stricture (RIS) or non-RIS and analyzed by stricture location. Cold knife incisions were made in a tri or quadrant fashion followed by intralesional injection of MMC and 1 month of once daily CIC. All 37 patients previously underwent at least 1 intervention for urethral stricture or BNC before VIU with MMC and CIC. Mean stricture length was 2.0 cm (range, 1-6 cm; standard deviation, 1.0 cm). Over the median follow-up period of 23 months (range, 12-39 months), 75.7% of patients required no additional surgical intervention (RIS, 54.5%; non-RIS, 84.6%; P = .051). In those that did recur, median time to stricture recurrence was 8 months (range, 2-28 months). One patient with recurrence required urethroplasty. VIU with MMC followed by short-term CIC provides a minimally invasive and widely available tool to manage complex recurrent urethral strictures (<3 cm) and BNC without significant morbidity. This approach may be most attractive for patients who are poor candidates for open surgery. Copyright © 2015 Elsevier Inc. All rights reserved.

Impact of prior urethral manipulation on outcome of anastomotic urethroplasty for post-traumatic urethral stricture.

PubMed

Singh, Bhupendra P; Andankar, Mukund G; Swain, Sanjaya K; Das, Krishanu; Dassi, Vimal; Kaswan, Harish K; Agrawal, Vipul; Pathak, Hemant R

2010-01-01

To determine the impact of earlier urethral interventions on the outcomes of anastomotic urethroplasty in post-traumatic stricture urethra. From October 1995 to March 2008, a total of 58 patients with post-traumatic posterior urethral stricture underwent anastomotic urethroplasty. Eighteen patients had earlier undergone urethral intervention in the form of urethrotomy (3), endoscopic realignment (7), or open urethroplasty (8). Success was defined as no obstructive urinary symptoms, maximum urine flow rate > or = 15 mL/s, normal urethral imaging and/or urethroscopy, and no need of any intervention in the follow-up period. Patients who met the above objective criteria after needing 1 urethrotomy following urethroplasty were defined to have satisfactory outcome and were included in satisfactory result rate along with patients who had a successful outcome. Results were analyzed using unpaired t test, chi-square test, binary logistic regression, Kaplan-Meier curves, and log rank test. Previous interventions in the form of endoscopic realignment or urethroplasty have significant adverse effect on the success rate of subsequent anastomotic urethroplasty for post-traumatic posterior urethral strictures (P <.05). Previous intervention in the form of visual internal urethrotomies (up to 2 times) did not affect the outcome of subsequent anastomotic urethroplasty. Length of stricture and age of patient did not predict the outcome in traumatic posterior urethral strictures in logistic regression analysis. Previous failed railroading or urethroplasty significantly decrease the success of subsequent anastomotic urethroplasty. Hence, a primary realignment or urethroplasty should be avoided in suboptimal conditions and the cases of post-traumatic urethral stricture should be referred to centers with such expertise. 2010 Elsevier Inc. All rights reserved.

Holmium laser urethrotomy for treatment of traumatic stricture urethra: a review of 78 patients.

PubMed

Hussain, Manzoor; Lal, Murli; Askari, Syed Hasan; Hashmi, Altaf; Rizvi, Syed Adibul Hasan

2010-10-01

To evaluate the efficacy and long-term results of laser urethrotomy as minimally invasive treatment for traumatic stricture urethra. Between January 2006 and June 2008, 78 male patients were treated with Holmium Laser urethrotomy. 16 Fr urethroscope was used through which 600um laser fiber was introduced through side channel. Stricture was visualized and incised at 12 o'clock position with energy set at 1500-2000 MJ at pulse rate of 10-12. Two other incisions were given at 2 and 10 o'clock positions. Further ablation was done till 16Fr Foley's catheter was passed. Patients were followed in a stricture clinic. Patients age ranged from 15-73 years. All strictures were due to trauma, Road traffic accident in 40 (52%) post catheter trauma 4 (5%), fall as ride 27 (35%) and failed urethroplasty 7 (8%). Site of stricture was bulbar 57 (73%), bulbomembranous 16 (20%) and membranoprostatic 5 (2.5%). Length of stricture ranged from 0.8-2.5 cms. At 3 months follow-up, 60 (77%) patients remained catheter and symptoms free while 18 (23%) developed recurrence of stricture but at the end of 36 months follow-up success rate decreased to 47 (60%). Among those who developed re-strictures, 6 ( 7.6%) had 2nd sitting laser while 4 (5.1%) had urethroplasty, and others were on intermittent dilatation. Immediate complications were sepsis 10 (13%), extravasation 2 (4%), failed urethrotomy 2 (4%) and mild haematuria 3 (5.8%). Hospital stay ranged from day care to 3 days. Laser urethrotomy is minimally invasive and an effective treatment for short strictures in bulbarurethra. The recurrence rate is 40% in the long-term follow-up and is more commonly seen in completely obliterated strictures.

Comparison of cold-knife optical internal urethrotomy and holmium:YAG laser internal urethrotomy in bulbar urethral strictures

PubMed Central

Yenice, Mustafa Gurkan; Sam, Emre; Colakoglu, Yunus; Atar, Feyzi Arda; Sahin, Selcuk; Simsek, Abdulmuttalip; Tugcu, Volkan

2017-01-01

Introduction To compare the results of cold-knife optical internal urethrotomy (OIU) and Holmium:YAG laser internal urethrotomy (HIU) in primary bulbar urethral strictures. Material and methods A total of 63 patients diagnosed with primary bulbar urethral stricture between August 2014 and September 2015 were assigned to the OIU (n = 29) and HIU (n = 34) groups. The demographic variables, biochemistry panels, and preoperative and postoperative uroflowmetry results including the maximum flow rate (Qmax) and mean flow rate (Qmean) values, retrograde urethrography, and diagnostic flexible urethroscopy findings were recorded prospectively. Demographic features and preoperative values were not statistically different between groups (p >0.05). Mean surgical times were 18.4 ±2.3 min for OIU and 21.9 ±3.8 min for HIU groups, which was statistically significant (p <0.05). There was no significant difference in complication rates in both groups (p = 0.618). Results Postoperative Qmax values were increased in both groups even though postoperative Qmax values were not significantly different between the two groups in the short- and long-term results at 3, 6, and 12 months (p >0.05). There was no recurrence in the first 3 months in either group. The urethral stricture recurrence rate up to month 12 was not statistically significant for the OIU group (n = 6, 20.7%) as compared to the HIU group (n = 11, 32.4%; p = 0.299). At follow-up, the SFR and IFR was 96% and 88% at 3-months, and 82% and 71% at 12-months, respectively (p <0.001). While almost three-quarters of patients were stone and infection free at 12-months, the majority of those with stones recurrence also had recurrence of their UTI. Conclusions HIU is an alternative method to OIU, and it has similar success rates in the treatment of short segment bulbar urethral strictures. PMID:29732217

Dorsal buccal mucosal graft urethroplasty by a ventral sagittal urethrotomy and minimal-access perineal approach for anterior urethral stricture.

PubMed

Gupta, N P; Ansari, M S; Dogra, P N; Tandon, S

2004-06-01

To present the technique of dorsal buccal mucosal graft urethroplasty through a ventral sagittal urethrotomy and minimal access perineal approach for anterior urethral stricture. From July 2001 to December 2002, 12 patients with a long anterior urethral stricture had the anterior urethra reconstructed, using a one-stage urethroplasty with a dorsal onlay buccal mucosal graft through a ventral sagittal urethrotomy. The urethra was approached via a small perineal incision irrespective of the site and length of the stricture. The penis was everted through the perineal wound. No urethral dissection was used on laterally or dorsally, so as not to jeopardize the blood supply. The mean (range) length of the stricture was 5 (3-16) cm and the follow-up 12 (10-16) months. The results were good in 11 of the 12 patients. One patient developed a stricture at the proximal anastomotic site and required optical internal urethrotomy. Dorsal buccal mucosal graft urethroplasty via a minimal access perineal approach is a simple technique with a good surgical outcome; it does not require urethral dissection and mobilization and hence preserves the blood supply.

Treatment of male urethral strictures - possible reasons for the use of repeated dilatation or internal urethrotomy rather than urethroplasty.

PubMed

Heyns, C F; van der Merwe, J; Basson, J; van der Merwe, A

2012-07-16

To investigate the possible reasons for repeated urethral dilatation or optical internal urethrotomy rather than urethroplasty in the treatment of male urethral strictures. Men referred to the stricture clinic of our institution during the period April 2007 - March 2008 were reviewed and the operative urological procedures performed in the same period were analysed. Statistical analysis was performed using Student's t-test and Fisher's exact test (p<0.05 statistically significant). The mean age of the 125 men was 49.9 years (range 12.8 - 93.4 years). Previous stricture treatment had been given 1 - 2, 3 - 4 and 5 - 6 times in 52%, 32% and 12% of patients, respectively (4% had not undergone treatment). In these groups, previous treatment was dilatation in 70%, 76% and 72%, urethrotomy in 26%, 15% and 28%, and urethroplasty in 4%, 9% and 0, respectively. The group with 5 - 6 compared with 1 - 2 previous treatments was significantly older (mean age 60.2 v. 46.6 years) and had a significantly greater proportion with underlying co-morbidities (80% v. 52%). The group that had undergone urethroplasty compared with 5 - 6 repeated dilatations or urethrotomies was significantly younger (mean age 48.2 v. 60.2 years) with a lower prevalence of co-morbidities (47% v. 80%). During the study period urethroplasty was performed in 16 (2%) of 821 inpatients, whereas 55 men were seen who had undergone ≥3 previous procedures, indicating that urethroplasty was performed in less than one-third of cases in which it would have been the optimal treatment. Owing to limited theatre time, procedures indicated for malignancy, urolithiasis, renal failure and congenital anomalies were performed more often than urethroplasty. Factors that possibly influenced the decision to perform repeated urethrotomy or dilatation instead of urethroplasty were limited theatre time, increased patient age and the presence of underlying co-morbidities.

Endoscopic laser-urethroplasty

NASA Astrophysics Data System (ADS)

Gilbert, Peter

2006-02-01

The objective was to prove the advantage of endoscopic laser-urethroplasty over internal urethrotomy in acquired urethral strictures. Patients and Method: From January, 1996 to June, 2005, 35 patients with a mean age of 66 years were submitted to endoscopic laser-urethroplasty for strictures of either the bulbar (30) or membranous (5) urethra. The operations were carried out under general anesthesia. First of all, the strictures were incised at the 4, 8 and 12 o'clock position by means of a Sachse-urethrotom. Then the scar flap between the 4 and 8 o'clock position was vaporized using a Nd:YAG laser, wavelength 1060 nm and a 600 pm bare fiber, the latter always being in contact with the tissue. The laser worked at 40W power in continuous mode. The total energy averaged 2574 J. An indwelling catheter was kept in place overnight and the patients were discharged the following day. Urinalysis, uroflowmetry and clinical examination were performed at two months after surgery and from then on every six months. Results: No serious complications were encountered. Considering a mean follow-up of 18 months, the average peak flow improved from 7.3 ml/s preoperatively to 18.7 mVs postoperatively. The treatment faded in 5 patients ( 14.3% ) who finally underwent open urethroplasty. Conclusions: Endoscopic laser-urethroplasty yields better short-term results than internal visual urethrotomy. Long-term follow-up has yet to confirm its superiority in the treatment of acquired urethral strictures.

Management of the stricture of fossa navicularis and pendulous urethral strictures

PubMed Central

Singh, Shrawan K.; Agrawal, Santosh K.; Mavuduru, Ravimohan S.

2011-01-01

Objective: Management of distal anterior urethral stricture is a common problem faced by practicing urologists. Literature on urethral stricture mainly pertains to bulbar urethral stricture and pelvic fracture urethral distraction defect. The present article aims to review the management of the strictures of fossa navicularis and pendulous urethra. Materials and Methods: The literature in English language was searched from the National Library of Medicine database, using the appropriate key words for the period 1985-2010. Out of 475 articles, 115 were selected for the review based on their relevance to the topic. Results: Etiology of stricture is shifting from infective to inflammatory and iatrogenic causes. Stricture of fossa navicularis is most often caused by lichen sclerosus et atrophicus and instrumentation. Direct visual internal urethrotomy is limited to selected cases in the management of pendulous urethral stricture. With experience and identification of various prognostic factors, conservative management by dilatation and internal urethrotomy is being replaced by various reconstructive procedures, using skin flaps and grafts with high success rates. Single-stage urethroplasty is preferred over the 2-stage procedure as the latter disfigures the penis and poses sexual problems temporarily. Conclusions: Flaps or grafts are useful for single-stage reconstruction of fossa navicularis and pendulous urethral strictures. The buccal and lingual mucosa serves as a preferred resource material for providing the inner lining of the urethra. Off-the-shelf materials, such as acellular collagen matrix, are promising. PMID:22022062

The Efficacy of Bulbar Urethral Mobilization for Anastomotic Anterior Urethroplasty in a Case With Recurrent Anterior Urethral Stricture

PubMed Central

Fukui, Shinji; Aoki, Katsuya; Kaneko, Yoshiteru; Samma, Shoji; Fujimoto, Kiyohide

2014-01-01

A 2-month-old boy was diagnosed with febrile urinary tract infection. Voiding cystourethrography showed bulbar and anterior urethral strictures, and endoscopic internal urethrotomy was performed. He developed febrile urinary tract infection again and revealed the recurrence of the anterior urethral stricture. Consequently, endoscopic internal urethrotomy was performed 4 times. Because the anterior urethral stricture had not improved, he was referred to us. Anterior urethroplasty was performed when he was 5 years. After excision of the scarred portions of the urethra, the defect of the urethra was 20 mm. Transperineal bulbar urethral mobilization was performed, and a single-stage end-to-end anterior urethroplasty without tension could be performed simultaneously. PMID:26955558

The Efficacy of Bulbar Urethral Mobilization for Anastomotic Anterior Urethroplasty in a Case With Recurrent Anterior Urethral Stricture.

PubMed

Fukui, Shinji; Aoki, Katsuya; Kaneko, Yoshiteru; Samma, Shoji; Fujimoto, Kiyohide

2014-05-01

A 2-month-old boy was diagnosed with febrile urinary tract infection. Voiding cystourethrography showed bulbar and anterior urethral strictures, and endoscopic internal urethrotomy was performed. He developed febrile urinary tract infection again and revealed the recurrence of the anterior urethral stricture. Consequently, endoscopic internal urethrotomy was performed 4 times. Because the anterior urethral stricture had not improved, he was referred to us. Anterior urethroplasty was performed when he was 5 years. After excision of the scarred portions of the urethra, the defect of the urethra was 20 mm. Transperineal bulbar urethral mobilization was performed, and a single-stage end-to-end anterior urethroplasty without tension could be performed simultaneously.

Simple urethral dilatation, endoscopic urethrotomy, and urethroplasty for urethral stricture disease in adult men.

PubMed

Wong, Susan S W; Aboumarzouk, Omar M; Narahari, Radhakrishna; O'Riordan, Anna; Pickard, Robert

2012-12-12

Strictures of the urethra are the most common cause of obstructed micturition in younger men and frequently recur after initial treatment. Standard treatment comprises internal widening of the strictured area by simple dilatation or by telescope-guided internal cutting (optical urethrotomy), but these interventions are associated with a high failure rate requiring repeated treatment. The alternative option of open urethroplasty whereby the urethral lumen is permanently widened by removal or grafting of the strictured segment is less likely to fail but requires greater expertise. Findings of Improved choice of graft material and shortened hospital stay suggest that urethroplasty may be under utilised. The extent and quality of evidence guiding treatment choice for this condition are uncertain.   To determine which is the best surgical treatment for male urethral stricture disease taking into account relative efficacy, adverse event rates and cost-effectiveness.   We searched the Cochrane Incontinence Group Specialised Register (searched 21 June 2012), CENTRAL (2012, Issue 6), MEDLINE (January 1946 to week 2 June 2012), EMBASE (January 1980 to week 25 2012), OpenSIGLE (searched 26 June 2012), clinical trials registries and reference lists of relevant articles. We included publications reporting data from randomised or quasi-randomised controlled trials comparing the effectiveness of dilatation, urethrotomy and urethroplasty in the treatment of adult men with urethral stricture disease. Two authors evaluated trials for appropriateness for inclusion and methodological quality. Data extraction was performed using predetermined criteria. Analyses were carried out using the Cochrane Review Manager software (RevMan 5). Two randomised trials were identified. One trial compared the outcomes of surgical urethral dilatation and optical urethrotomy in 210 adult men with urethral stricture disease. No significant difference was found in the proportion of men being stricture free at three years or in the median time to recurrence. The second trial compared the outcomes of urethrotomy and urethroplasty in 50 men with traumatic stricture of the posterior urethra following pelvic fracture injury. In the first six months, men were more likely to require further surgery in the urethrotomy group than in the primary urethroplasty group (RR 3.39, 95% CI 1.62 to 7.07). After two years, 16 of 25 (64%) men initially treated by urethrotomy required continued self-dilatation or further surgery for stricture recurrence compared to 6 of 25 (24%) men treated by primary urethroplasty. There were insufficient data to perform meta-analysis or to reliably determine effect size. There were insufficient data to determine which intervention is best for urethral stricture disease in terms of balancing efficacy, adverse effects and costs. Well designed, adequately powered multi-centre trials are needed to answer relevant clinical questions regarding treatment of men with urethral strictures.

Visual internal urethrotomy for management of urethral strictures in boys: a comparison of short-term outcome of holmium laser versus cold knife.

PubMed

Aboulela, Waseem; ElSheemy, Mohammed S; Shoukry, Mahmoud; Shouman, Ahmed M; Shoukry, Ahmed I; Ghoneima, Waleed; El Ghoneimy, Mohamed; Morsi, Hany A; Mohsen, Mostafa Abdel; Badawy, Hesham

2018-04-01

To compare efficacy and safety of visual internal urethrotomy (VIU) using holmium laser (Ho:YAG) (group A) versus cold knife (group B) in children with urethral strictures. It may be the first comparative study on this issue in children. This study compared Ho:YAG group, which was evaluated prospectively from January 2014 till January 2016, versus cold knife group, which was a historical control performed from March 2008 till February 2010. Children ≤ 13 years old with urethral strictures ≤ 1.5 cm were included successively. Recurrent cases, congenital obstructions and cases with complete arrest of dye in voiding cystourethrography were excluded. Scar tissue was incised at twelve o'clock. Outcome was compared using Student's t, Mann-Whitney, Chi-square or Fisher exact tests as appropriate. Each group included 21 patients. Mean age was 6.27 ± 3.23 (2-13) years old. Mean stricture length was 1.02 versus 1 cm in group A versus B, respectively (p = 0.862). Ten cases of penile/bulbous strictures and another 11 cases of membranous strictures were found in each group. There was no significant difference between both groups in preoperative data. Success rate for initial VIU was 66.7% in group A versus 38% in group B (p = 0.064). This was associated with significantly higher Q max in group A (mean 16.52 vs 12.09 ml/s; p = 0.03). Success rate after two trials of VIU was 76.2% for group A and 47.61% for group B (p = 0.057). No complications were reported in both groups. Laser VIU has a higher success rate than cold knife VIU for urethral strictures ≤ 1.5 cm in children with significantly higher Q max . Both are easy to perform, low invasive and safe.

Long-term outcome of urethroplasty after failed urethrotomy versus primary repair.

PubMed

Barbagli, G; Palminteri, E; Lazzeri, M; Guazzoni, G; Turini, D

2001-06-01

A urethral stricture recurring after repeat urethrotomy challenges even a skilled urologist. To address the question of whether to repeat urethrotomy or perform open reconstructive surgery, we retrospectively review a series of 93 patients comparing those who underwent primary repair versus those who had undergone urethrotomy and underwent secondary treatment. From 1975 to 1998, 93 males between age 13 and 78 years (mean 39) underwent surgical treatment for bulbar urethral stricture. In 46 (49%) of the patients urethroplasty was performed as primary repair, and in 47 (51%) after previously failed urethrotomy. The strictures were localized in the bulbous urethra without involvement of penile or membranous tracts. The etiology was ischemic in 37 patients, traumatic in 23, unknown in 17 and inflammatory in 16. To simplify evaluation of the results, the clinical outcome was considered either a success or a failure at the time any postoperative procedure was needed, including dilation. In our 93 patients primary urethroplasty had a final success rate of 85%, and after failed urethrotomy 87%. Previously failed urethrotomy did not influence the long-term outcome of urethroplasty. The long-term results of different urethroplasty techniques had a final success rate ranging from 77% to 96%. We conclude that failed urethrotomy does not condition the long-term result of surgical repair. With extended followup, the success rate of urethroplasty decreases with time but it is in fact still higher than that of urethrotomy.

Management of bladder neck stenosis and urethral stricture and stenosis following treatment for prostate cancer.

PubMed

Nicholson, Helen L; Al-Hakeem, Yasser; Maldonado, Javier J; Tse, Vincent

2017-07-01

The aim of this review is to examine all urethral strictures and stenoses subsequent to treatment for prostate cancer, including radical prostatectomy (RP), radiotherapy, high intensity focused ultrasound (HIFU) and cryotherapy. The overall majority respond to endoscopic treatment, including dilatation, direct visual internal urethrotomy (DVIU) or bladder neck incision (BNI). There are adjunct treatments to endoscopic management, including injections of corticosteroids and mitomycin C (MMC) and urethral stents, which remain controversial and are not currently mainstay of treatment. Recalcitrant strictures are most commonly managed with urethroplasty, while recalcitrant stenosis is relatively rare yet almost always associated with bothersome urinary incontinence, requiring bladder neck reconstruction and subsequent artificial urinary sphincter (AUS) implantation, or urinary diversion for the devastated outlet.

Management of bladder neck stenosis and urethral stricture and stenosis following treatment for prostate cancer

PubMed Central

Nicholson, Helen L.; Al-Hakeem, Yasser; Maldonado, Javier J.

2017-01-01

The aim of this review is to examine all urethral strictures and stenoses subsequent to treatment for prostate cancer, including radical prostatectomy (RP), radiotherapy, high intensity focused ultrasound (HIFU) and cryotherapy. The overall majority respond to endoscopic treatment, including dilatation, direct visual internal urethrotomy (DVIU) or bladder neck incision (BNI). There are adjunct treatments to endoscopic management, including injections of corticosteroids and mitomycin C (MMC) and urethral stents, which remain controversial and are not currently mainstay of treatment. Recalcitrant strictures are most commonly managed with urethroplasty, while recalcitrant stenosis is relatively rare yet almost always associated with bothersome urinary incontinence, requiring bladder neck reconstruction and subsequent artificial urinary sphincter (AUS) implantation, or urinary diversion for the devastated outlet. PMID:28791228

Simple urethral dilatation, endoscopic urethrotomy, and urethroplasty for urethral stricture disease in adult men.

PubMed

Wong, Susan S W; Narahari, Radhakrishna; O'Riordan, Anna; Pickard, Robert

2010-04-14

Strictures of the urethra are the commonest cause of obstructed micturition in younger men and frequently recur after initial treatment. Standard treatment comprises internal widening of the strictured area by simple dilatation or by telescope-guided internal cutting (optical urethrotomy), but these interventions are associated with a high failure rate requiring repeated treatment. The alternative option of open urethroplasty whereby the urethral lumen is permanently widened by removal or grafting of the strictured segment is less likely to fail but requires greater expertise. Improved choice of graft material and shortened hospital stay suggest urethroplasty may be under used. The extent and quality of evidence guiding treatment choice for this condition is uncertain. To determine which is the best surgical treatment for male urethral stricture disease taking into account relative efficacy, adverse event rates and cost-effectiveness. We searched the Cochrane Incontinence Group Specialised Register (searched 26 March 2009), CENTRAL (2009, Issue 1), MEDLINE (January 1950 to March 2009), EMBASE (January 1980 to March 2009), OpenSIGLE (searched 26 March 2009), clinical trials registries and reference lists of relevant articles. We included publications reporting data from randomised or quasi-randomised controlled trials comparing the effectiveness of dilatation, urethrotomy and urethroplasty in the treatment of adult men with urethral stricture disease. Two authors evaluated trials for appropriateness for inclusion and methodological quality. Data extraction was performed using predetermined criteria. Analyses were carried out using the Cochrane Review Manager software; RevMan 5. Two randomised trials were identified. One trial compared the outcome of surgical urethral dilatation and optical urethrotomy in 210 adult men with urethral stricture disease. No significant difference was found in the proportion of men being stricture free at three years or in the median time to recurrence. The second trial compared the outcome of urethrotomy and urethroplasty in 50 men with traumatic stricture of the posterior urethra following pelvic fracture injury. After two years 16 of 25 (64%) men initially treated by urethrotomy required continued self-dilatation or further surgery for stricture recurrence compared to 6 of 25 (24%) men treated by primary urethroplasty. There was insufficient data to perform meta-analysis or to reliably determine effect size. There were insufficient data to determine which intervention is best for urethral stricture disease in terms of balancing efficacy, adverse effects and costs. Well designed, adequately powered multi-centre trials are needed to answer relevant clinical questions regarding treatment of men with urethral strictures.

Development of a clinical algorithm for treating urethral strictures based on a large retrospective single-center cohort

PubMed Central

Tolkach, Yuri; Herrmann, Thomas; Merseburger, Axel; Burchardt, Martin; Wolters, Mathias; Huusmann, Stefan; Kramer, Mario; Kuczyk, Markus; Imkamp, Florian

2017-01-01

Aim: To analyze clinical data from male patients treated with urethrotomy and to develop a clinical decision algorithm. Materials and methods: Two large cohorts of male patients with urethral strictures were included in this retrospective study, historical (1985-1995, n=491) and modern cohorts (1996-2006, n=470). All patients were treated with repeated internal urethrotomies (up to 9 sessions). Clinical outcomes were analyzed and systemized as a clinical decision algorithm. Results: The overall recurrence rates after the first urethrotomy were 32.4% and 23% in the historical and modern cohorts, respectively. In many patients, the second procedure was also effective with the third procedure also feasible in selected patients. The strictures with a length ≤ 2 cm should be treated according to the initial length. In patients with strictures ≤ 1 cm, the second session could be recommended in all patients, but not with penile strictures, strictures related to transurethral operations or for patients who were 31-50 years of age. The third session could be effective in selected cases of idiopathic bulbar strictures. For strictures with a length of 1-2 cm, a second operation is possible for the solitary low-grade bulbar strictures, given that the age is > 50 years and the etiology is not post-transurethral resection of the prostate. For penile strictures that are 1-2 cm, urethrotomy could be attempted in solitary but not in high-grade strictures. Conclusions: We present data on the treatment of urethral strictures with urethrotomy from a single center. Based on the analysis, a clinical decision algorithm was suggested, which could be a reliable basis for everyday clinical practice. PMID:28529689

Outcome of buccal mucosa urethroplasty in the management of urethral strictures.

PubMed

Cakiroglu, Basri; Sinanoglu, Orhun; Arda, Ersan

2017-06-30

The objective of the study is to report the outcome of buccal mucosal urethroplasty. The follow up data of 15 patients undergoing single stage urethroplasty from September 2010 to September 2015 were retropectively reviewed. They received buccal mucosa graft for urethroplasty. The patients were followed for complications and outcome. Mean age was 53.7 ± 13.6 The stricture length ranged from 3 to 6 cm (mean 4.4 ± 0.8). The success rate for buccal mucosa urethroplasty (BMU) was 67.7% at 12th month. Three patients presenting with voiding difficulty in the 3rd month and one in the next 12 months, had urethral restenosis. One patient had fistula formation at 6th month postoperatively. Five patients underwent retreatment procedures such as internal urethrotomy, urethroplasty and/or internal urethrotomy. The buccal mucosa is easy to obtain and handle, therefore BMU can be safely and effectively managed outside high volume institutions.

[Low-dose rate brachytherapy with locally integrated beta emitters after internal urethrotomy. A pilot project using an animal model].

PubMed

Weidlich, P; Adam, C; Sroka, R; Lanzl, I; Assmann, W; Stief, C

2007-09-01

The treatment of urethral strictures represents an unsolved urological problem. The effect of a (32)P-coated urethral catheter in the sense of low-dose rate brachytherapy to modulate wound healing will be analyzed in an animal experiment. Unfortunately it is not possible to present any results because this is being studied for the first time and there are no experiences with low-dose rate brachytherapy and this form of application in the lower urinary tract. Furthermore the animal experiment will only start in the near future. Both decade-long experiences with radiotherapy to treat benign diseases and our own results of previous studies in otolaryngology and ophthalmology let us expect a significantly lower formation of urethral strictures after internal urethrotomy. This study will contribute to improving the treatment of urethral strictures as demanded in previous papers.

A Comparative Study of Dorsal Buccal Mucosa Graft Substitution Urethroplasty by Dorsal Urethrotomy Approach versus Ventral Sagittal Urethrotomy Approach.

PubMed

Pahwa, Mrinal; Gupta, Sanjeev; Pahwa, Mayank; Jain, Brig D K; Gupta, Manu

2013-01-01

Objectives. To compare the outcome of dorsal buccal mucosal graft (BMG) substitution urethroplasty by dorsal urethrotomy approach with ventral urethrotomy approach in management of stricture urethra. Methods and Materials. A total of 40 patients who underwent dorsal BMG substitution urethroplasty were randomized into two groups. 20 patients underwent dorsal onlay BMG urethroplasty as described by Barbagli, and the other 20 patients underwent dorsal BMG urethroplasty by ventral urethrotomy as described by Asopa. Operative time, success rate, satisfaction rate, and complications were compared between the two groups. Mean follow-up was 12 months (6-24 months). Results. Ventral urethrotomy group had considerably lesser operative time although the difference was not statistically significant. Patients in dorsal group had mean maximum flow rate of 19.6 mL/min and mean residual urine of 27 mL, whereas ventral group had a mean maximum flow rate of 18.8 and residual urine of 32 mL. Eighteen out of twenty patients voided well in each group, and postoperative imaging study in these patients showed a good lumen with no evidence of leak or extravasation. Conclusion. Though ventral sagittal urethrotomy preserves the blood supply of urethra and intraoperative time was less than dorsal urethrotomy technique, there was no statistically significant difference in final outcome using either technique.

A Comparative Study of Dorsal Buccal Mucosa Graft Substitution Urethroplasty by Dorsal Urethrotomy Approach versus Ventral Sagittal Urethrotomy Approach

PubMed Central

Pahwa, Mrinal; Gupta, Sanjeev; Pahwa, Mayank; Jain, Brig D. K.; Gupta, Manu

2013-01-01

Objectives. To compare the outcome of dorsal buccal mucosal graft (BMG) substitution urethroplasty by dorsal urethrotomy approach with ventral urethrotomy approach in management of stricture urethra. Methods and Materials. A total of 40 patients who underwent dorsal BMG substitution urethroplasty were randomized into two groups. 20 patients underwent dorsal onlay BMG urethroplasty as described by Barbagli, and the other 20 patients underwent dorsal BMG urethroplasty by ventral urethrotomy as described by Asopa. Operative time, success rate, satisfaction rate, and complications were compared between the two groups. Mean follow-up was 12 months (6–24 months). Results. Ventral urethrotomy group had considerably lesser operative time although the difference was not statistically significant. Patients in dorsal group had mean maximum flow rate of 19.6 mL/min and mean residual urine of 27 mL, whereas ventral group had a mean maximum flow rate of 18.8 and residual urine of 32 mL. Eighteen out of twenty patients voided well in each group, and postoperative imaging study in these patients showed a good lumen with no evidence of leak or extravasation. Conclusion. Though ventral sagittal urethrotomy preserves the blood supply of urethra and intraoperative time was less than dorsal urethrotomy technique, there was no statistically significant difference in final outcome using either technique. PMID:24194754

Outcome of urethral strictures treated by endoscopic urethrotomy and urethroplasty

PubMed Central

Tinaut-Ranera, Javier; Arrabal-Polo, Miguel Ángel; Merino-Salas, Sergio; Nogueras-Ocaña, Mercedes; López-León, Víctor Manuel; Palao-Yago, Francisco; Arrabal-Martín, Miguel; Lahoz-García, Clara; Alaminos, Miguel; Zuluaga-Gomez, Armando

2014-01-01

Introduction: We analyze the outcomes of patients with urethral stricture who underwent surgical treatment within the past 5 years. Methods: This is a retrospective study of male patients who underwent surgery for urethral stricture at our service from January 2008 to June 2012. We analyzed the comorbidities, type, length and location of the stricture and the surgical treatment outcome after endoscopic urethrotomy, urethroplasty or both. Results: In total, 45 patients with a mean age of 53.7 ± 16.7 years underwent surgical treatment for urethral stricture. Six months after surgery, 46.7% of the patients had a maximum urinary flow greater than 15 mL/s, whereas 87.3% of the patients exhibited no stricture by urethrography after the treatment. The success rate in the patients undergoing urethrotomy was 47.8% versus 86.4% in those undergoing urethroplasty (p = 0.01). Twenty percent of the patients in whom the initial urethrotomy had failed subsequently underwent urethroplasty, thereby increasing the treatment success. Conclusion: In most cases, the treatment of choice for urethral stricture should be urethroplasty. Previous treatment with urethrotomy does not appear to produce adverse effects that affect the outcome of a urethroplasty if urethrotomy failed, so urethrotomy may be indicated in patients with short strictures or in patients at high surgical risk. PMID:24454595

Outcome of urethral strictures treated by endoscopic urethrotomy and urethroplasty.

PubMed

Tinaut-Ranera, Javier; Arrabal-Polo, Miguel Ángel; Merino-Salas, Sergio; Nogueras-Ocaña, Mercedes; López-León, Víctor Manuel; Palao-Yago, Francisco; Arrabal-Martín, Miguel; Lahoz-García, Clara; Alaminos, Miguel; Zuluaga-Gomez, Armando

2014-01-01

We analyze the outcomes of patients with urethral stricture who underwent surgical treatment within the past 5 years. This is a retrospective study of male patients who underwent surgery for urethral stricture at our service from January 2008 to June 2012. We analyzed the comorbidities, type, length and location of the stricture and the surgical treatment outcome after endoscopic urethrotomy, urethroplasty or both. In total, 45 patients with a mean age of 53.7 ± 16.7 years underwent surgical treatment for urethral stricture. Six months after surgery, 46.7% of the patients had a maximum urinary flow greater than 15 mL/s, whereas 87.3% of the patients exhibited no stricture by urethrography after the treatment. The success rate in the patients undergoing urethrotomy was 47.8% versus 86.4% in those undergoing urethroplasty (p = 0.01). Twenty percent of the patients in whom the initial urethrotomy had failed subsequently underwent urethroplasty, thereby increasing the treatment success. In most cases, the treatment of choice for urethral stricture should be urethroplasty. Previous treatment with urethrotomy does not appear to produce adverse effects that affect the outcome of a urethroplasty if urethrotomy failed, so urethrotomy may be indicated in patients with short strictures or in patients at high surgical risk.

Trends in stricture management among male Medicare beneficiaries: underuse of urethroplasty?

PubMed

Anger, Jennifer T; Buckley, Jill C; Santucci, Richard A; Elliott, Sean P; Saigal, Christopher S

2011-02-01

To analyze the trends in male urethral stricture management using the 1992-2001 Medicare claims data and to determine whether certain racial and ethnic groups have a disproportionate burden of urethral stricture disease. We analyzed the Medicare claims for fiscal years 1992, 1995, 1998, and 2001. The "International Classification of Disease, 9th revision," diagnosis codes were used to identify men with urethral stricture. The demographic characteristics assessed included patient age, race, and comorbidities, as measured using the Charlson index. Treatments were identified using the Physician Current Procedural Terminology Coding System, 4th edition, procedure codes and stratified into 4 treatment types: urethral dilation, direct vision internal urethrotomy, urethral stent/steroid injection, and urethroplasty. The overall rates of stricture diagnosis decreased from 10,088/100,000 population in 1992 to 6897 in 2001 (from 1.4% to 0.9%). The stricture prevalence was greatest among black and Hispanic men, although the urethroplasty rates were greatest among white men. Direct vision internal urethrotomy was the most common treatment, followed by urethral dilation, urethral stent/steroid injection, and urethroplasty. The urethroplasty rates remained stable, but quite low (0.6%-0.8%), during the study period. The overall rates of stricture diagnosis decreased from 1992 to 2001. Despite the poor overall efficacy of urethrotomy and urethral dilation relative to urethroplasty and despite the known complications of stent placement in this setting, the urethroplasty rates were the lowest of all treatments. Although we could not determine the treatment success with these data, these findings suggest an underuse of the most efficacious treatment of urethral stricture disease, urethroplasty. Copyright © 2011. Published by Elsevier Inc.

Outcomes of Endoscopic Realignment of Pelvic Fracture Associated Urethral Injuries at a Level 1 Trauma Center

PubMed Central

Leddy, Laura S.; Vanni, Alex J.; Wessells, Hunter; Voelzke, Bryan B.

2012-01-01

Purpose We examined the success of early endoscopic realignment of pelvic fracture associated urethral injury after blunt pelvic trauma. Materials and Methods A retrospective review was performed of patients with pelvic fracture associated urethral injury who underwent early endoscopic realignment using a retrograde or retrograde/antegrade approach from 2004 to 2010 at a Level 1 trauma center. Followup consisted of uroflowmetry, post-void residual and cystoscopic evaluation. Failure of early endoscopic realignment was defined as patients requiring urethral dilation, direct vision internal urethrotomy, posterior urethroplasty or self-catheterization after initial urethral catheter removal. Results A total of 19 consecutive patients (mean age 38 years) with blunt pelvic fracture associated urethral injury underwent early endoscopic realignment. Twelve cases of complete urethral disruption, 4 of incomplete disruption and 3 of indeterminate status were noted. Mean time to realignment was 2 days and mean duration of urethral catheterization after realignment was 53 days. One patient was lost to followup after early endoscopic realignment. Using an intent to treat analysis early endoscopic realignment failed in 15 of 19 patients (78.9%). Mean time to early endoscopic realignment failure after catheter removal was 79 days. The cases of early endoscopic realignment failure were managed with posterior urethroplasty (8), direct vision internal urethrotomy (3) and direct vision internal urethrotomy followed by posterior urethroplasty (3). Mean followup for the 4 patients considered to have undergone successful early endoscopic realignment was 2.1 years. Conclusions Early endoscopic realignment after blunt pelvic fracture associated urethral injury results in high rates of symptomatic urethral stricture requiring further operative treatment. Close followup after initial catheter removal is warranted, as the mean time to failure after early endoscopic realignment was 79 days in our cohort. PMID:22591965

Managing many patients with a urethral stricture: a cost-benefit analysis of treatment options.

PubMed

Ogbonna, B C

1998-05-01

To report a management method in a community where there are many patients with urethral stricture and where the short-term goal of providing some treatment to most may override the sometimes conflicting long-term aim of minimizing recurrence rates. Over a 3-year period, using optical urethrotomy in 76 patients followed by intermittent self-dilatation (ISD) in 29, urethroplasty in 28 and dilatation in three, 92 of 134 patients with a urethral stricture were treated and the outcome compared. The overall recurrence rate was 22%; a combination of urethrotomy plus ISD had a recurrence rate of 17% and gave a mean duration of follow-up without recurrence similar to that after urethroplasty. ISD significantly increased both the time before recurrence and the duration of follow-up without recurrence after urethrotomy. In addition to providing lasting treatment to many patients, urethrotomy was also 10 times cheaper, 10 times faster to perform and offered the surgeon better protection from infection with human immunodeficiency virus than did urethroplasty. Because wrongly selecting urethrotomy (resulting in a failed procedure) wastes valuable operating time and resources, the pre-operative recognition of strictures unsuitable for urethrotomy and their treatment by urethroplasty is important for overall efficiency.

Neodymium-YAG laser core through urethrotomy in obliterative posttraumatic urethral strictures after failed initial urethroplasty.

PubMed

Dogra, P N; Nabi, G

2002-01-01

To assess the feasibility, problems and results of Nd-YAG laser core through urethrotomy in the management of failed urethroplasty for posttraumatic bulbomembranous urethral strictures. 61 patients with obliterative posttraumatic urethral strictures were treated by Nd-YAG laser core through urethrotomy between May 1997 to April 2000. Of these, 5 patients had failed end-to-end urethroplasty done as an initial procedure at various periods of time. The procedure was performed as day care and patients were discharged within 6 h of procedure. At 24-30 months of follow-up, all patients are voiding well and are continent. Auxiliary procedures were required in 2 cases. Nd-YAG laser core through urethrotomy is a feasible day care option for patients of obliterative urethral strictures following failed initial urethroplasty with successful outcome. Copyright 2002 S. Karger AG, Basel

Treatment of bulbar urethral strictures a review, with personal critical remarks.

PubMed

Oosterlinck, Willem

2003-05-27

This is a review article on treatment of bulbar urethral strictures with personal critical remarks on newer developments. As a treatment of first intention there exists 4 options : dilatation, urethrotomy, end to end anastomosis and free graft, open urethroplasty. Success rate of dilatation and visual urethrotomy after 4 years is only 20 en 40% respectively. Laser urethrotomy could not fulfill expectations. End to end anastomosis obtains a very high success rate but is only applicable for short strictures. Free graft urethroplasty obtains success rates of +/- 80%. There is considerable debate on the best material for grafting. Buccal mucosa graft is the new wave, but this is not based on scientific data. Whether this graft should be used dorsally or ventrally is also a point of discussion. In view of the good results published with both techniques it is probably of no importance. Intraluminal stents are not indicated for complicated cases and give only good results in those cases which can easily be treated with other techniques. Metal self-retaining urethral stent, resorbable stents and endoscopic urethroplasty is briefly discussed. Redo's and complicated urethral strictures need often other solutions. Here skin flap from the penile skin and scrotal flap can be used. Advantages and drawbracks of both are discussed. There is still a place for two-stage procedures in complicated redo"s. The two-stage mesh-graft urethroplasty offers advantage over the use of scrotal skin. Some other rare techniques like substitution with bowel and pudendal thigh flap, to cover deep defects, are also discussed.

Predictors of urethral stricture recurrence after endoscopic urethrotomy.

PubMed

Redón-Gálvez, L; Molina-Escudero, R; Álvarez-Ardura, M; Otaola-Arca, H; Alarcón Parra, R O; Páez-Borda, Á

2016-10-01

The aim of the study was to analyse the clinical-demographic variables of the series and the predictors of urethral stricture recurrence after endoscopic urethrotomy. We retrospectively analysed 67 patients who underwent Sachse endoscopic urethrotomy between June 2006 and September 2014. Those patients who had previously undergone endoscopic urethrotomy or urethroplasty were excluded. The other patients who presented urethral stricture were included. We analysed age, weight, smoking habit, and cardiovascular risk factors, as well as the number, location, length and aetiology of the strictures, previous urethrotomies, vesical catheter duration and postsurgical dilatations. A univariate and multivariate analysis was conducted using the chi-squared test or Fisher's test and logistic regression to identify the variables related to recurrence. Thirty-seven percent of the patients had a relapse. The majority of the patients were older than 60 years (56.7%), obese (74.6%), nonsmokers (88%) and had no cardiovascular factors (56.7%). The majority of the strictures were single (94%), <1cm (82%), bulbar urethral (64.2%), iatrogenic (67.2%) and with no prior urethrotomy (89.6%). The majority of the patients carried a vesical catheter for <15 days (85.1%) and did not undergo postsurgical dilatation (65.7%). Only the length of the stricture was an independent risk factor for recurrence (P=.025; relative risk, 5.7; 95% CI 1.21-26.41). In the treatment of urethral strictures through endoscopic urethrotomy, a stricture length >1cm is the only factor that predicts an increase in the risk of recurrence. We found no clinical or demographic factors that caused an increase in the incidence of recurrence. Similarly, technical factors such as increasing the bladder catheterisation time and urethral dilatations did not change the course of the disease. Their routine use is therefore unnecessary. Copyright © 2016 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

[Buccal mucosa graft augmented anastomotic urethroplasty for the treatment of bulbar urethral strictures].

PubMed

Virasoro, Ramón; Storme, Oscar Alfonso; Capiel, Leandro; Ghisini, Diego Andrés; Rovegno, AugustÍn

2015-12-01

To report our outcomes with the use of buccal mucosal graft anastomotic urethroplasty to reconstruct complex anterior urethral strictures. Between October 2007 and January 2011 we conducted a retrospective review of a series of 65 patients from 2 different centers. We analyzed demographic data, surgical outcomes and complications. Patient mean age was 50.09 years (range: 25 to 75), mean stricture length was 3.95 cm (range: 3 to 7 cm) and mean follow-up 33.13 months (range: 12.7 to 52.77). Eighty percent of patients had prior treatments, mainly direct visual internal urethrotomy (DVIU) and urethral dilatation. Most frequent etiologies were iatrogenic in 46.15% of patients and idiopathic in 35.38% of patients. Success rate was achieved in 96.92% of patients; only 2 patients presented recurrence and were treated successfully with one DVIU. Clavien Dindo I-II complications were found in 59% of patients. No patient had chronic sequels. Augmented anastomotic urethroplasty using dorsal onlay buccal mucosa graft enables correction, in one time, of long segment urethral strictures with severe spongiofibrosis and/or obliterated lumen. Our outcomes are comparable with those of previously reported in international series.

Male urethral strictures and their management

PubMed Central

Hampson, Lindsay A.; McAninch, Jack W.; Breyer, Benjamin N.

2014-01-01

Male urethral stricture disease is prevalent and has a substantial impact on quality of life and health-care costs. Management of urethral strictures is complex and depends on the characteristics of the stricture. Data show that there is no difference between urethral dilation and internal urethrotomy in terms of long-term outcomes; success rates range widely from 8–80%, with long-term success rates of 20–30%. For both of these procedures, the risk of recurrence is greater for men with longer strictures, penile urethral strictures, multiple strictures, presence of infection, or history of prior procedures. Analysis has shown that repeated use of urethrotomy is not clinically effective or cost-effective in these patients. Long-term success rates are higher for surgical reconstruction with urethroplasty, with most studies showing success rates of 85–90%. Many techniques have been utilized for urethroplasty, depending on the location, length, and character of the stricture. Successful management of urethral strictures requires detailed knowledge of anatomy, pathophysiology, proper patient selection, and reconstructive techniques. PMID:24346008

Internal Urethrotomy With Intralesional Mitomycin C: An Effective Option for Endoscopic Management of Recurrent Bulbar and Bulbomembranous Urethral Strictures.

PubMed

Farrell, M Ryan; Lawrenz, Cedric W; Levine, Laurence A

2017-12-01

To describe our experience with direct visual internal urethrotomy (DVIU) and mitomycin C (MMC) for recurrent bulbar and bulbomembranous urethral strictures of radiation and non-radiation-induced etiologies. We reviewed our database of consecutive patients presenting to our tertiary care institution with recurrent bulbar and bulbomembranous urethral strictures who underwent DVIU with MMC from 2011 to 2016. Patients were stratified by radiation-induced strictures (RIS) vs non-RIS. Cold-knife incisions were made at 12-, 3-, and 9-o'clock positions followed by intralesional injection of 10 mL MMC (0.4 mg/mL) in 0.2-0.4 mL aliquots and 1 month of postoperative daily clean intermittent catheterization (CIC). All 44 patients (RIS n = 18, non-RIS n = 26) failed prior endoscopic management or urethroplasty. Median stricture length was 2.0 cm (interquartile range [IQR] 1.0-2.5). Over a median follow-up of 25.8 months (IQR 12.9-47.2), 75.0% of patients (33/44) required no additional surgical intervention (RIS 12/18, 66.7%; non-RIS 21/26, 80.8%). Median time to stricture recurrence among those who recurred was 10.7 months (IQR 3.9-17.6; RIS 9.4 months, IQR 3.5-17.6; non-RIS 11.2 months, IQR 8.0-25.6). Four patients (RIS n = 2, non-RIS n = 2) elected to undergo urethroplasty for recurrence. A second DVIU with MMC was performed in the remaining recurrences (n = 7) with no further surgical intervention required in 37 of 40 of patients (92.5%) overall (RIS 14/16, 87.5%; non-RIS 23/24, 95.8%). No long-term complications were attributable to MMC. DVIU with MMC and short-term CIC for recurrent, short, bulbar and bulbomembranous urethral strictures is a safe endoscopic modality with promising early results. This approach may be useful for patients who are suboptimal candidates for open reconstruction. Copyright © 2017 Elsevier Inc. All rights reserved.

Dorsal buccal mucosal graft urethroplasty for anterior urethral stricture by Asopa technique.

PubMed

Pisapati, V L N Murthy; Paturi, Srimannarayana; Bethu, Suresh; Jada, Srikanth; Chilumu, Ramreddy; Devraj, Rahul; Reddy, Bhargava; Sriramoju, Vidyasagar

2009-07-01

Buccal mucosal graft (BMG) substitution urethroplasty has become popular in the management of intractable anterior urethral strictures with good results. Excellent long-term results have been reported by both dorsal and ventral onlay techniques. Asopa reported a successful technique for dorsal placement of BMG in long anterior urethral strictures through a ventral sagittal approach. To evaluate prospectively the results and advantages of dorsal BMG urethroplasty for recurrent anterior urethral strictures by a ventral sagittal urethrotomy approach (Asopa technique). From December 2002 to December 2007, a total of 58 men underwent dorsal BMG urethroplasty by a ventral sagittal urethrotomy approach for recurrent urethral strictures. Forty-five of these patients with a follow-up period of 12-60 mo were prospectively evaluated, and the results were analysed. The urethra was split twice at the site of the stricture both ventrally and dorsally without mobilising it from its bed, and the buccal mucosal graft was secured in the dorsal urethral defect. The urethra was then retubularised in one stage. The overall results were good (87%), with a mean follow-up period of 42 mo. Seven patients developed minor wound infection, and five patients developed fistulae. There were six recurrences (6:45, 13%) during the follow-up period of 12-60 mo. Two patients with a panurethral stricture and four with bulbar or penobulbar strictures developed recurrences and were managed by optical urethrotomy and self-dilatation. The medium-term results were as good as those reported with the dorsal urethrotomy approach. Long-term results from this and other series are awaited. More randomised trials and meta-analyses are needed to establish this technique as a procedure of choice in future. The ventral sagittal urethrotomy approach is easier to perform than the dorsal urethrotomy approach, has good results, and is especially useful in long anterior urethral strictures.

Dorsal free graft urethroplasty for urethral stricture by ventral sagittal urethrotomy approach.

PubMed

Asopa, H S; Garg, M; Singhal, G G; Singh, L; Asopa, J; Nischal, A

2001-11-01

To explore the feasibility of applying a dorsal free graft to treat urethral stricture by the ventral sagittal urethrotomy approach without mobilizing the urethra. Twelve patients with long or multiple strictures of the anterior urethra were treated by a dorsal free full-thickness preputial or buccal mucosa graft. The urethra was not separated from the corporal bodies and was opened in the midline over the stricture. The floor of the urethra was incised, and an elliptical raw area was created over the tunica on which a free full-thickness graft of preputial or buccal mucosa was secured. The urethra was retubularized in one stage. After a follow-up of 8 to 40 months, one recurrence developed and required dilation. The ventral sagittal urethrotomy approach for dorsal free graft urethroplasty is not only feasible and successful, but is easy to perform.

Versatility of the ventral approach in bulbar urethroplasty using dorsal, ventral or dorsal plus ventral oral grafts.

PubMed

Palminteri, Enzo; Berdondini, Elisa; Fusco, Ferdinando; De Nunzio, Cosimo; Giannitsas, Kostas; Shokeir, Ahmed A

2012-06-01

To investigate the versatility of the ventral urethrotomy approach in bulbar reconstruction with buccal mucosa (BM) grafts placed on the dorsal, ventral or dorsal plus ventral urethral surface. Between 1999 and 2008, 216 patients with bulbar strictures underwent BM graft urethroplasty using the ventral-sagittal urethrotomy approach. Of these patients, 32 (14.8%; mean stricture 3.2 cm, range 1.5-5) had a dorsal graft urethroplasty (DGU), 121 (56%; mean stricture 3.7, range 1.5-8) a ventral graft urethroplasty (VGU), and 63 (29.2%; mean stricture 3.4, range 1.5-10) a dorsal plus ventral graft urethroplasty (DVGU). The strictured urethra was opened by a ventral-sagittal urethrotomy and BM graft was inserted dorsally or ventrally or dorsal plus ventral to augment the urethral plate. The median follow-up was 37 months. The overall 5-year actuarial success rate was 91.4%. The 5-year actuarial success rates were 87.8%, 95.5% and 86.3% for the DGU, VGU and DVGU, respectively. There were no statistically significant differences among the three groups. Success rates decreased significantly only with a stricture length of >4 cm. In BM graft bulbar urethroplasties the ventral urethrotomy access is simple and versatile, allowing an intraoperative choice of dorsal, ventral or combined dorsal and ventral grafting, with comparable success rates.

Temporary vesicostomy-assisted urethroplasty for recurrent obliterated posterior urethral stricture.

PubMed

Liu, Jui-Ming; Wang, Ta-Min; Chiang, Yang-Jen; Chen, Hsiao-Wen; Chu, Sheng-Hsien; Liu, Kuan-Lin; Lin, Kuo-Jen

2012-01-01

We report the outcomes of temporary vesicostomy- assisted anastomotic urethroplasty in patients with recurrent obliterated posterior urethral stricture. A review of the medical records identified 12 men (mean age 35.8 years) who had undergone anastomotic urethroplasty for recurrent obliterated posterior stricture. Preoperative evaluation of the urethral defect included a simultaneous retrograde urethrogram and cystogram. The mean estimated preoperative radiographic length of the urethral disruption was 4.25 cm. All patients underwent 1-stage bulboprostatic anastomotic repair which was assisted by an intraoperative temporary vesicostomy. The initial objective success rate was 83%. The mean follow-up was 22 months. Voiding cystourethrography performed postoperatively demonstrated a wide, patent anastomosis in all but two cases. Urethroscopy performed 1 month after surgery revealed a patent anastomosis with normal urethral mucosa in all but two patients. The mean peak flow rate at the last follow-up visit was 16.3 ml/s. Two patients developed an anastomotic stricture 6 weeks after surgery that was successfully treated by direct visual internal urethrotomy. Finally, all patients had a patent urethra after salvage treatment postoperatively. An open 1-stage temporary vesicostomy- assisted urethroplasty for recurrent obliterated posterior urethral stricture provides satisfactory outcomes and minimal morbidities.

Pelvic fracture-associated urethral injuries in girls: experience with primary repair.

PubMed

Dorairajan, Lalgudi N; Gupta, Harendra; Kumar, Santosh

2004-07-01

To present our experience with four urethral injuries in females accompanying a pelvic fracture, managed with primary repair or realignment of the urethra. There were three teenage girls and one adult (22 years old). All the patients had complete urethral injuries associated with a pelvic fracture from accidents. They were managed by immediate suprapubic cystostomy followed by repair or realignment of the urethra over a catheter on the same day. The catheter was removed after 3 weeks and a voiding cysto-urethrogram taken. Thereafter they were followed with regular urethral calibration. All patients voided satisfactorily with a good stream; three were fully continent and the fourth had transient stress urinary incontinence. One patient needed dilatation at 2 months and another visual internal urethrotomy at 5 months. At a mean (range) follow-up of 33 (9-60) months all the patients had a normal voiding pattern and were continent; none developed vaginal stenosis. Primary repair of the urethra, and if that is impossible, simple urethral realignment over a catheter, is the procedure of choice for managing female urethral injury associated with a pelvic fracture. The procedure has the additional advantage of reducing the risk of vaginal stenosis.

[Transurethral thulium laser urethrotomy for urethral stricture].

PubMed

Liu, Chun-Lai; Zhang, Xi-Ling; Liu, Yi-Li; Wang, Ping

2011-09-01

To evaluate the effect of endourethrotomy with thulium laser as a minimally invasive treatment for urethral stricture. We treated 36 cases of urethral stricture or atresia by endourethrotomy with thulium laser, restored the urethral continuity by vaporization excision of the scar tissue, and observed the clinical effects and complications. The mean operation time was 35 min, ranging from 10 to 90 min. Smooth urination was achieved after 2-6 weeks of catheter indwelling, with no urinary incontinence. The patients were followed up for 4-24 (mean 12) months, during which 27 did not need any reintervention, 5 developed urinary thinning but cured by urethral dilation, 3 received another laser urethrotomy for previous negligence of timely urethral dilation, and the other 1 underwent open urethroplasty. Thulium laser urethrotomy is a safe and effective minimally invasive option for short urethral stricture, which is also suitable for severe urethral stricture and urethral atresia. Its short-term outcome is satisfactory, but its long-term effect remains to be further observed.

Versatility of the ventral approach in bulbar urethroplasty using dorsal, ventral or dorsal plus ventral oral grafts

PubMed Central

Palminteri, Enzo; Berdondini, Elisa; Fusco, Ferdinando; Nunzio, Cosimo De; Giannitsas, Kostas; Shokeir, Ahmed A.

2012-01-01

Objectives To investigate the versatility of the ventral urethrotomy approach in bulbar reconstruction with buccal mucosa (BM) grafts placed on the dorsal, ventral or dorsal plus ventral urethral surface. Patients and methods Between 1999 and 2008, 216 patients with bulbar strictures underwent BM graft urethroplasty using the ventral-sagittal urethrotomy approach. Of these patients, 32 (14.8%; mean stricture 3.2 cm, range 1.5–5) had a dorsal graft urethroplasty (DGU), 121 (56%; mean stricture 3.7, range 1.5–8) a ventral graft urethroplasty (VGU), and 63 (29.2%; mean stricture 3.4, range 1.5–10) a dorsal plus ventral graft urethroplasty (DVGU). The strictured urethra was opened by a ventral-sagittal urethrotomy and BM graft was inserted dorsally or ventrally or dorsal plus ventral to augment the urethral plate. Results The median follow-up was 37 months. The overall 5-year actuarial success rate was 91.4%. The 5-year actuarial success rates were 87.8%, 95.5% and 86.3% for the DGU, VGU and DVGU, respectively. There were no statistically significant differences among the three groups. Success rates decreased significantly only with a stricture length of >4 cm. Conclusions In BM graft bulbar urethroplasties the ventral urethrotomy access is simple and versatile, allowing an intraoperative choice of dorsal, ventral or combined dorsal and ventral grafting, with comparable success rates. PMID:26558013

Transrectal ultrasound-guided extraction of impacted prostatic urethral calculi: a simple alternative to endoscopy

PubMed Central

Amend, Gregory; Gandhi, Jason; Smith, Noel L.; Weissbart, Steven J.; Schulsinger, David A.; Joshi, Gargi

2017-01-01

Urethral stones can become impacted in the posterior urethra, typically presenting with varying degrees of acute urinary retention and lower urinary tract symptoms. These are traditionally treated in the inpatient setting, with external urethrotomy or endoscopic push-back of the calculus into the urinary bladder followed by cystolitholapaxy or cystolithotripsy. However, these methods are invasive, involve general anesthesia, and require radiation. In this report, we describe a simple, minimally invasive, and safe alternative technique to visualize and remove impacted prostatic urethral stones under the real-time guidance of transrectal ultrasonography (TRUS). The urologist can accomplish this procedure in the office, avoiding radiation exposure to the patient and hospital admission. PMID:28725602

Surgical treatment of an acquired posterior urethral diverticulum with cystoscopy assisted robotic technique.

PubMed

Guneri, Cagri; Kirac, Mustafa; Biri, Hasan

2017-03-01

A 42-year-old man with a history of recurrent urethral stenosis, recurrent urinary tract infection and macroscopic hematuria has referred to our clinic. He underwent several internal urethrotomies and currently using clean intermittent self-catheterization. During the internal urethrotomy, we noted a large posterior urethral diverticulum (UD) between verumontanum and bladder neck. His obstructive symptoms were resolved after the catheter removal. But perineal discomfort, urgency and dysuria were prolonged about 3-4 weeks. Urinalysis and urine culture confirmed recurrent urinary tract infections. Due to this conditions and symptoms, we planned a surgical approach which was planned as transperitoneal robotic-assisted laparoscopic approach. This technique is still applied for the diverticulectomy of the bladder. In addition to this we utilized the cystoscopy equipments for assistance. During this process, cystoscope was placed in the UD to help the identification of UD from adjacent tissues like seminal vesicles by its movement and translumination. Operating time was 185 min. On the post-operative third day he was discharged. Foley catheter was removed after 2 weeks. Urination was quite satisfactory. His perineal discomfort was resolved. The pathology report confirmed epidermoid (tailgut) cyst of the prostate. Urethrogram showed no radiologic signs of UD after 4 weeks. Irritative and obstructive symptoms were completely resolved after 3 months. No urinary incontinence, erectile dysfunction or retrograde ejaculation was noted. While posterior UD is an extremely rare situation, surgical treatment of posterior UD remains uncertain. To our knowledge, no above-mentioned cystoscopy assisted robotic technique for the treatment was described in the literature.

Aggressive Angiomyxoma Involving Penis and Urethra - A Case Report.

PubMed

Damodaran, Shivashankar; Gengan, Devakannan; Walling, Sashi T

2017-07-01

Aggressive angiomyxoma is a rare benign mesenchymal stromal tumour, characterized by locally infiltrative nature and a tendency for recurrence. Only a few cases of penile involvement have been reported in the literature so far. We report a case of aggressive penile angiomyxoma in a sixty-two-year-old obese, diabetic male patient. He presented with obstructive lower urinary tract symptoms (LUTS) and diffuse enlargement of the penis and scrotum. He was managed with excision, reduction scrotoplasty, internal urethrotomy, followed by Leuprolide therapy for prevention of recurrence. He is on follow up for 20 months without recurrence and obstructive symptoms.

[Endoscopic realignment with drainage via a peel-away sheath for the treatment of urethral rupture: A report of 21 cases].

PubMed

Han, Cong-Xiang; Xu, Wei-Jie; Li, Wei; Yu, Zhong-Ying; Li, Jin-Yu; Lin, Xia-Cong; Zhao, Li

2016-07-01

To study the clinical effect endoscopic realignment with drainage via a peel-away sheath in the treatment of urethral rupture. We treated 21 urethral rupture patients by endoscopic realignment with drainage via a peel-away sheath using normal saline for irrigation under the normal nephroscope or Li Xun nephroscope, followed by analysis of the clinical results. The operation was successfully accomplished in 20 cases but failed in 1 and none experienced urinary extravasation. In the 14 cases of bulbar urethral rupture, the mean operation time was (5.1±1.6) min and the mean Foley catheter indwelling time was (26.0±5.1) d. Urethral stricture developed in 57.1% (8/14) of the cases after catheter removal, of which 1 was cured by internal urethrotomy and the other 7 by urethral sound dilation, with an average maximum urinary flow rate of (18.8±1.8) ml/s at 12 months after operation. In the 6 cases of posterior urethral rupture, the mean operation time was (15.8±7.5) min and the mean Foley catheter indwelling time was 8 weeks. Urethral stricture developed in all the 6 cases after catheter removal, of which 3 cases were cured by urethral dilation, 1 by internal urethrotomy, and 2 by open urethroplasty. The average maxium urinary flow rate of the 4 cases exempt from open surgery was (17.9±1.9) ml/s at 12 months after operation. Endoscopic realignment with drainage via a peel-away sheath can keep the operative field clear, avoid intraoperative rinse extravasation, shorten the operation time, improve the operation success rate, and achieve satisfactory early clinical outcomes in the treatment of either bulbar or posterior urethral rupture.

Is there a way to predict failure after direct vision internal urethrotomy for single and short bulbar urethral strictures?

PubMed Central

Harraz, Ahmed M.; El-Assmy, Ahmed; Mahmoud, Osama; Elbakry, Amr A.; Tharwat, Mohamed; Omar, Helmy; Farg, Hashim; Laymon, Mahmoud; Mosbah, Ahmed

2015-01-01

Objective To identify patient and stricture characteristics predicting failure after direct vision internal urethrotomy (DVIU) for single and short (<2 cm) bulbar urethral strictures. Patients and methods We retrospectively analysed the records of adult patients who underwent DVIU between January 2002 and 2013. The patients’ demographics and stricture characteristics were analysed. The primary outcome was procedure failure, defined as the need for regular self-dilatation (RSD), redo DVIU or substitution urethroplasty. Predictors of failure were analysed. Results In all, 430 adult patients with a mean (SD) age of 50 (15) years were included. The main causes of stricture were idiopathic followed by iatrogenic in 51.6% and 26.3% of patients, respectively. Most patients presented with obstructive lower urinary tract symptoms (68.9%) and strictures were proximal bulbar, i.e. just close to the external urethral sphincter, in 35.3%. The median (range) follow-up duration was 29 (3–132) months. In all, 250 (58.1%) patients did not require any further instrumentation, while RSD was maintained in 116 (27%) patients, including 28 (6.5%) who required a redo DVIU or urethroplasty. In 64 (6.5%) patients, a redo DVIU or urethroplasty was performed. On multivariate analysis, older age at presentation [odds ratio (OR) 1.017; P = 0.03], obesity (OR 1.664; P = 0.015), and idiopathic strictures (OR 3.107; P = 0.035) were independent predictors of failure after DVIU. Conclusion The failure rate after DVIU accounted for 41.8% of our present cohort with older age at presentation, obesity, and idiopathic strictures independent predictors of failure after DVIU. This information is important in counselling patients before surgery. PMID:26609447

Is there a way to predict failure after direct vision internal urethrotomy for single and short bulbar urethral strictures?

PubMed

Harraz, Ahmed M; El-Assmy, Ahmed; Mahmoud, Osama; Elbakry, Amr A; Tharwat, Mohamed; Omar, Helmy; Farg, Hashim; Laymon, Mahmoud; Mosbah, Ahmed

2015-12-01

To identify patient and stricture characteristics predicting failure after direct vision internal urethrotomy (DVIU) for single and short (<2 cm) bulbar urethral strictures. We retrospectively analysed the records of adult patients who underwent DVIU between January 2002 and 2013. The patients' demographics and stricture characteristics were analysed. The primary outcome was procedure failure, defined as the need for regular self-dilatation (RSD), redo DVIU or substitution urethroplasty. Predictors of failure were analysed. In all, 430 adult patients with a mean (SD) age of 50 (15) years were included. The main causes of stricture were idiopathic followed by iatrogenic in 51.6% and 26.3% of patients, respectively. Most patients presented with obstructive lower urinary tract symptoms (68.9%) and strictures were proximal bulbar, i.e. just close to the external urethral sphincter, in 35.3%. The median (range) follow-up duration was 29 (3-132) months. In all, 250 (58.1%) patients did not require any further instrumentation, while RSD was maintained in 116 (27%) patients, including 28 (6.5%) who required a redo DVIU or urethroplasty. In 64 (6.5%) patients, a redo DVIU or urethroplasty was performed. On multivariate analysis, older age at presentation [odds ratio (OR) 1.017; P = 0.03], obesity (OR 1.664; P = 0.015), and idiopathic strictures (OR 3.107; P = 0.035) were independent predictors of failure after DVIU. The failure rate after DVIU accounted for 41.8% of our present cohort with older age at presentation, obesity, and idiopathic strictures independent predictors of failure after DVIU. This information is important in counselling patients before surgery.

Direct Vision Internal Urethrotomy for Short Anterior Urethral Strictures and Beyond: Success Rates, Predictors of Treatment Failure, and Recurrence Management.

PubMed

Kluth, Luis A; Ernst, Lukas; Vetterlein, Malte W; Meyer, Christian P; Reiss, C Philip; Fisch, Margit; Rosenbaum, Clemens M

2017-08-01

To determine success rates, predictors of recurrence, and recurrence management of patients treated for short anterior urethral strictures by direct vision internal urethrotomy (DVIU). We identified 128 patients who underwent DVIU of the anterior urethra between December 2009 and March 2016. Follow-up was conducted by telephone interviews. Success rates were assessed by Kaplan-Meier estimators. Predictors of stricture recurrence and different further therapy strategies were identified by uni- and multivariable Cox regression analyses. The mean age was 63.8 years (standard deviation: 16.3) and the overall success rate was 51.6% (N = 66) at a median follow-up of 16 months (interquartile range: 6-43). Median time to stricture recurrence was six months (interquartile range: 2-12). In uni- and multivariable analyses, only repeat DVIU (hazard ratio [HR] = 1.87, 95% confidence interval (CI) = 1.13-3.11, P= .015; and HR=1.78, 95% CI = 1.05-3.03, P = .032, respectively) was a risk factor for recurrence. Of 62 patients with recurrence, 35.5% underwent urethroplasty, 29% underwent further endoscopic treatment, and 33.9% did not undergo further interventional therapy. Age (HR = 1.05, 95% CI = 1.01-1.09, P = .019) and diabetes (HR = 2.90, 95% CI = 1.02-8.26, P = .047) were predictors of no further interventional therapy. DVIU seems justifiable in short urethral strictures as a primary treatment. Prior DVIU was a risk factor for recurrence. In case of recurrence, about one-third of the patients did not undergo any further therapy. Higher age and diabetes predicted the denial of any further treatment. Copyright © 2017 Elsevier Inc. All rights reserved.

[Oral mucosa graft urethroplasty for complicated urethral strictures].

PubMed

Horiguchi, Akio; Sumitomo, Makoto; Kanbara, Taiki; Tsujita, Yujiro; Yoshii, Takahiko; Yoshii, Hidehiko; Satoh, Akinori; Asakuma, Junichi; Ito, Keiichi; Hayakawa, Masamichi; Asano, Tomohiko

2010-03-01

We evaluated the efficacy and outcome of one-stage oral mucosa graft urethroplasty, which is currently the procedure of choice for treating lengthy and complicated urethral strictures not amenable to excision and primary end-to-end anastomosis. Seven patients 33 to 74 years old (mean age = 53.7) underwent one-stage oral mucosa graft urethroplasty for a stricture in either the bulbar urethra (four patients), penile urethra (two patients), or pan-anterior urethra (one patient). Three of the strictures were due to trauma, one was due to inflammation, and one was due to a failed hypospadia repair. The other two were iatrogenic. All patients had previously undergone either internal urethrotomy or repeated urethral dilation. Three patients received a tube graft, three received a ventral onlay, and one received a dorsal onlay. A free graft of oral mucosa was harvested from the inside of each patient's left cheek, and if necessary to obtain a sufficient length, the harvest was extended to include mucosa from the lower lip and the right cheek. The graft lengths ranged from 2.5 to 12 cm (mean = 4.6 cm). A urethral catheter was left in place for 3 weeks postoperatively. While no severe complications at the donor site were observed during follow-up periods ranging from 3 to 55 months (mean = 14 months), two patients who had received a tube graft developed distal anastomotic ring strictures that were managed by internal urethrotomy. The other five required no postoperative urological procedure even though one who had received a ventral onlay developed a penoscrotal fistula. Oral mucosa is an ideal urethral graft, and oral mucosa graft urethroplasty is an effective procedure for repairing complicated urethral strictures involving long portions of the urethra.

Internal urethrotomy in patients with recurrent urethral stricture after buccal mucosa graft urethroplasty.

PubMed

Rosenbaum, Clemens M; Schmid, Marianne; Ludwig, Tim A; Kluth, Luis A; Reiss, Philip; Dahlem, Roland; Engel, Oliver; Chun, Felix K-H; Riechardt, Silke; Fisch, Margit; Ahyai, Sascha A

2015-09-01

To determine the success rate of direct vision internal urethrotomy (DVIU) in the treatment of short stricture recurrence after buccal mucosa graft urethroplasty (BMGU). Patients who underwent DVIU for the treatment of short, "veil-like" recurrent urethral strictures (<1 cm) after BMGU between October 2009 and 2013 were retrospectively identified within our urethroplasty database. Stricture recurrence was defined as maximum flow rate (Q max) <15 ml/s and a consecutively verified stricture in a combined retro- and antegrade voiding cystography or cystoscopy at a follow-up visit. The success rate of DVIU was assessed by Kaplan-Meier analysis. Univariable Cox regression analyses evaluated risk factors for stricture recurrence following DVIU. Forty-three patients underwent DVIU for short stricture recurrence after BMGU for bulbar (81.3 %), penile (14.0 %) and membranous (4.7 %) strictures. Relapse had occurred proximally to the buccal mucosa graft in 28 (65.1 %) and distally in 12 (27.9 %) patients, respectively. At a mean follow-up of 11.7 (±9.7) months, stricture recurrence was observed in 48.8 % of our patients. Stricture recurrence was significantly associated with weak urinary stream (9.3 ml/s vs. no recurrence 19.5 ml/s) and patient dissatisfaction (66.7 % vs. no recurrence 18.1 %; both p < 0.001). The overall success rate was 60.5 % 15 months after DVIU. The main limitations of this study are its retrospective design, the small sample size and the short follow-up. DVIU after BMGU showed a moderate success rate and therefore might be a viable treatment option in selected patients with very short strictures after BMGU. However, longer follow-up is warranted to prove long-term effectiveness.

Evaluation and management of anterior urethral stricture disease

PubMed Central

Mangera, Altaf; Osman, Nadir; Chapple, Christopher

2016-01-01

Urethral stricture disease affects many men worldwide. Traditionally, the investigation of choice has been urethrography and the management of choice has been urethrotomy/dilatation. In this review, we discuss the evidence behind the use of ultrasonography in stricture assessment. We also discuss the factors a surgeon should consider when deciding the management options with each individual patient. Not all strictures are identical and surgeons should appreciate the poor long-term results of urethrotomy/dilatation for strictures longer than 2 cm, strictures in the penile urethra, recurrent strictures, and strictures secondary to lichen sclerosus. These patients may benefit from primary urethroplasty if they have many adverse features or secondary urethroplasty after the first recurrence. PMID:26918169

Repeat urethrotomy and dilation for the treatment of urethral stricture are neither clinically effective nor cost-effective.

PubMed

Greenwell, T J; Castle, C; Andrich, D E; MacDonald, J T; Nicol, D L; Mundy, A R

2004-07-01

We developed an algorithm for the management of urethral stricture based on cost-effectiveness. United Kingdom medical and hospital costs associated with the current management of urethral stricture were calculated using private medical insurance schedules of reimbursement and clean intermittent self-catheterization supply costs. These costs were applied to 126 new patients treated endoscopically for urethral stricture in a general urological setting between January 1, 1991 and December 31, 1999. Treatment failure was defined as recurrent symptomatic stricture requiring further operative intervention following initial intervention. Mean followup available was 25 months (range 1 to 132). The costs were urethrotomy/urethral dilation 2,250.00 pounds sterling (3,375.00 dollars, ratio 1.00), simple 1-stage urethroplasty 5,015.00 pounds sterling (7,522.50 dollars, ratio 2.23), complex 1-stage urethroplasty 5,335.00 pounds sterling (8,002.50 dollars, ratio 2.37) and 2-stage urethroplasty 10,370 pounds sterling (15,555.00 dollars, ratio 4.61). Of the 126 patients assessed 60 (47.6%) required more than 1 endoscopic retreatments (mean 3.13 each), 50 performed biweekly clean intermittent self-catheterization and 7 underwent urethroplasty during followup. The total cost per patient for all 126 patients for stricture treatment during followup was 6,113 pounds sterling (9,170 dollars). This cost was calculated by multiplying procedure cost by the number of procedures performed. A strategy of urethrotomy or urethral dilation as first line treatment, followed by urethroplasty for recurrence yielded a total cost per patient of 5,866 pounds sterling (8,799 dollars). A strategy of initial urethrotomy or urethral dilation followed by urethroplasty in patients with recurrent stricture proves to be the most cost-effective strategy. This financially based strategy concurs with evidence based best practice for urethral stricture management.

Urethral pull-through operation for the management of pelvic fracture urethral distraction defects.

PubMed

Yin, Lei; Li, Zhenhua; Kong, Chuize; Yu, Xiuyue; Zhu, Yuyan; Zhang, Yuxi; Jiang, Yuanjun

2011-10-01

To present our institutional experience in the management of pelvic fracture urethral distraction defects with urethral pull-through operation. Seventy-six patients (average age 34.5 years) with posterior urethral strictures caused by pelvic fracture urethral distraction defects underwent urethral pull-through operation at our department from July 1995 to September 2009. The estimated urethral stricture length was 2.0-3.5 cm (mean 2.5). Of these patients, 31 (41%) had undergone failed urethroplasty or urethrotomy after the initial management, and 5 (7%) had urethrorectal fistula. Urethral pull-through operation was performed 4-7 months (mean 4.9) after initial treatment or failed urethral reconstruction. The clinical outcome was considered a failure when any postoperative intervention was needed. Follow-up was 14-74 months (mean 42.5). The overall success rate was 89% (68/76). All treatment failures occurred within the first 6 months postoperatively. Failed repairs were successfully managed with internal urethrotomy in 1 patient, by urethral dilation in 6, and by another urethroplasty in 1. All patients were urinary-continent postoperatively. Of the potent patients, 2 (5%) became impotent after urethroplasty. There was no chordee, penile shortening, or urethral fistula recurrence. Urethral pull-through operation might be a less demanding and less time-consuming procedure. It does not increase the rate of impotence or incontinence and, with a high success rate, might serve as an alternative method for the management of pelvic fracture urethral distraction defects. Copyright © 2011 Elsevier Inc. All rights reserved.

Use of the holmium:YAG laser in urology

NASA Astrophysics Data System (ADS)

Mattioli, Stefano

1997-12-01

The Holmium-YAG is a versatile laser with multiple soft- tissue applications including tissue incision and vaporization, and pulsed-laser applications such as lithotripsy. At 2140 nanometers, the wavelength is highly absorbed by tissue water. Further, like CO2 laser, the Holmium produces immediate tissue vaporization while minimizing deep thermal damage to surrounding tissues. It is an excellent instrument for endopyelotomy, internal urethrotomy, bladder neck incisions and it can be used to resect the prostate. The Holmium creates an acute TUR defect which gives immediate results like the TURP. More than 50 patients were treated from Jan. 1996 to Jan. 1997 for obstructive symptoms due to benign prostatic hyperplasia, bladder neck stricture, urethral stenosis, and superficial bladder tumors.

Single-Staged Improved Tubularized Preputial/Penile Skin Flap Urethroplasty for Obliterated Anterior Urethral Stricture: Long-Term Results.

PubMed

Xue, Jing-Dong; Xie, Hong; Fu, Qiang; Feng, Chao; Guo, Hui; Xu, Yue-Min

2016-01-01

To present an improved tubularized flap (ITF) technique and report the outcome of single-stage urethroplasty using preputial/penile skin flaps (PSFs) for the treatment of obliterative anterior urethral strictures (AUSs). From January 2000 to June 2012, 42 cases of obliterative AUS (3-14 cm, mean 6.38 cm) with urethral plate unsalvageable were treated using PSF-ITF urethroplasty including longitudinal skin flap, circular island flap, L-flap, Q-flap. Patients were divided into 3 groups: pendulous urethral stricture (Group A), bulbar urethral stricture (Group B) and panurethral strictures (Group C). Patients were followed up by uroflowmetry, urethrography and ureteroscope when necessary. The mean follow-up in these patients was 65 months (range 36 months-15 years). The primary success rates at 3-year follow-up were 75, 75 and 60% for Groups A, B and C, respectively. The overall success rates were 85, 83 and 70% with the remedial measure of a single visual internal urethrotomy at 3-year follow-up. A total 60% of the patients in the study completed more than 5 years of follow-up with no additional recurrence. Improved tubularized preputial/PSF urethroplasty with relatively high overall satisfaction is a novel technique for treatment of AUS when there is inadequate urethral plate or obliterative defects. © 2016 S. Karger AG, Basel.

[Redo urethroplasty with buccal mucosa].

PubMed

Rosenbaum, C M; Ernst, L; Engel, O; Dahlem, R; Fisch, M; Kluth, L A

2017-10-01

Urethral strictures can occur on the basis of trauma, infections, iatrogenic-induced or idiopathic and have a great influence on the patient's quality of life. The current prevalence rate of male urethral strictures is 0.6% in industrialized western countries. The favored form of treatment has experienced a transition from less invasive interventions, such as urethrotomy or urethral dilatation, to more complex open surgical reconstruction. Excision and primary end-to-end anastomosis and buccal mucosa graft urethroplasty are the most frequently applied interventions with success rates of more than 80%. Risk factors for stricture recurrence after urethroplasty are penile stricture location, the length of the stricture (>4 cm) and prior repeated endoscopic therapy attempts. Radiation-induced urethral strictures also have a worse outcome. There are various therapy options in the case of stricture recurrence after a failed urethroplasty. In the case of short stricture recurrences, direct vision urethrotomy shows success rates of approximately 60%. In cases of longer or more complex stricture recurrences, redo urethroplasty should be the therapy of choice. Success rates are higher than after urethrotomy and almost comparable to those of primary urethroplasty. Patient satisfaction after redo urethroplasty is high. Primary buccal mucosa grafting involves a certain rate of oral morbidity. In cases of a redo urethroplasty with repeated buccal mucosa grafting, oral complications are only slightly higher.

Dorsal onlay lingual mucosal graft urethroplasty for urethral strictures in women.

PubMed

Sharma, Girish K; Pandey, Ashwani; Bansal, Harbans; Swain, Sameer; Das, Suren K; Trivedi, Sameer; Dwivedi, Udai S; Singh, Pratap B

2010-05-01

To describe the technique and results of dorsal onlay lingual mucosal graft (LMG) urethroplasty for the definitive management of urethral strictures in women. In all, 15 women (mean age 42 years) with a history suggestive of urethral stricture who had undergone multiple urethral dilatations and/or urethrotomy were selected for dorsal onlay LMG urethroplasty after thorough evaluation, from October 2006 to March 2008. After a suprameatal inverted-U incision, the dorsal aspect of the urethra was dissected and urethrotomy was done at the 12 o'clock position across the strictured segment. Tailored LMG harvested from the ventrolateral aspect of the tongue was then sutured to the urethrotomy wound over an 18 F silicone catheter. The preoperative mean maximum urinary flow rate of 7.2 mL/s increased to 29.87 mL/s, 26.95 mL/s and 26.86 mL/s with a 'normal' flow rate curve at 3, 6 and 12 months follow-up, respectively. One patient at the 3-month follow-up had submeatal stenosis and required urethral dilatation thrice at monthly intervals. At the 1-year follow-up, none of the present patients had any neurosensory complications, urinary incontinence, or long-term functional/aesthetic complication at the donor site. LMG urethroplasty using the dorsal onlay technique should be offered for correction of persistent female urethral stricture as it provides a simple, safe and effective approach with durable results.

Predictors for success of internal urethrotomy in patients with urethral contracture following perineal repair of pelvic fracture urethral injuries.

PubMed

Hong, Young-Kwon; Choi, Kyung-Hwa; Lee, Young-Tae; Lee, Seung-Ryeol

2017-05-01

Internal urethrotomy (IU) in patients with urethral contracture following perineal repair of pelvic fracture urethral injuries (PRPFUI) is troublesome. We evaluated the clinical factors affecting the surgical outcome of IU for urethral contracture after PRPFUI. We retrospectively reviewed the records of 35 patients who underwent IU for urethral contracture after PRPFUI between March 2004 and June 2013. Ages of patients ranged from 18 to 50, and their follow-up duration was more than 1year after IU. The urethral contracture was confirmed by retrograde urethrogram or cysto-urethroscopy. Success was defined as greater than 15mL/s of peak urinary flow rate at 1year after IU without any clinical evidence of urethral contracture. Success rates were investigated according to the number of IU. Age, body mass index, urethral defect length before PRPFUI, time interval between the original urethral injury and the PRPFUI or between a previous operation and the PRPFUI, time interval between the PRPFUI and the urethral contracture, number of PRPFUI performed, and the type of urethral lengthening procedure were compared between patients with and without success according to the number of IU. Among the 35 patients, the overall success rate of IU was 37% (13/35) during the mean follow-up period of 53 months (range: 17-148 months). There were 8 and 5 patients with success in first and second IU, respectively. However, there was no success after third IU. Urethral defect length before PRPFUI was significantly shorter in patients with success who underwent first and second IU (p<0.05). There were significant differences of success between patients with and without previous repeated failures of PRPFUI in first and second IU (p<0.05). Short urethral defect length and no previous surgical failures before PRPFUI are good prognostic factors for IU following PRPFUI. Only one or two IUs will be helpful in patients with urethral contracture following PRPFUI. Copyright © 2017 Elsevier Ltd. All rights reserved.

TRENDS IN STRICTURE MANAGEMENT AMONG MALE MEDICARE BENEFICIARIES: UNDERUSE OF URETHROPLASTY?

PubMed Central

Anger, Jennifer T.; Buckley, Jill C.; Santucci, Richard A.; Elliott, Sean P.; Saigal, Christopher S.

2012-01-01

Objectives We sought to analyze trends in male urethral stricture management through the use of 1992–2001 Medicare claims data, and to determine whether certain racial and ethnic groups bear a disproportionate burden of urethral stricture disease. Methods We analyzed Medicare claims for fiscal years 1992, 1995, 1998, and 2001. ICD-9 diagnosis codes were used to identify men with urethral stricture. Demographic characteristics assessed included patient age, race, and comorbidities as measured by the Charlson index. Treatments were identified by CPT-4 procedure codes and stratified into four treatment types: (1) urethral dilation, (2) direct vision internal urethrotomy (DVIU), (3) urethral stent/steroid injection, and (4) urethroplasty. Results Overall rates of stricture diagnosis decreased from 10,088 per 100,000 population in 1992 to 6,897 in 2001 (1.4% to 0.9%). Stricture prevalence was highest among African American and Hispanic men, although urethroplasty rates were highest among Caucasians. DVIU was the most common treatment, followed by urethral dilation, urethral stent/steroid injection, and urethroplasty. Urethroplasty rates remained stable, but quite low (0.6–0.8%), over the period of study. Conclusions Overall rates of stricture diagnosis decreased from 1992 to 2001. Despite the poor overall efficacy of urethrotomy and urethral dilation relative to urethroplasty, and despite the known complications of stent placement in this setting, urethroplasty rates were the lowest of all treatments. Although we cannot determine treatment success with these data, these findings suggest an underuse of the most efficacious treatment for urethral stricture disease, urethroplasty. PMID:21168194

Anterior urethral stricture review

PubMed Central

Stein, Marshall J.

2013-01-01

Male anterior urethral stricture disease is a commonly encountered condition that presents to many urologists. According to a National Practice Survey of Board Certified Urologist in the United States most urologists treat on average 6-20 urethral strictures yearly. Many of those same urologists surveyed treat with repeated dilation or internal urethrotomy, despite continual recurrence of the urethral stricture. In point of fact, the urethroplasty despite its high success rate, is underutilized by many practicing urologists. Roughly half of practicing urologist do not perform urethroplasty in the United States. Clearly, the reconstructive ladder for urethral stricture management that was previously described in the literature may no longer apply in the modern era. The following article reviews the etiology, diagnosis, management and comparisons of treatment options for anterior urethral strictures. PMID:26816721

1-Stage delayed bulboprostatic anastomotic repair of posterior urethral rupture: 60 patients with 1-year followup.

PubMed

Corriere, J N

2001-02-01

The long-term results of delayed 1-stage bulboprostatic anastomotic urethroplasty for posterior urethral ruptures are evaluated. A total of 63, 1-stage delayed repairs of complete posterior urethral ruptures in 60 men with at least 1-year followup were reviewed. Two ruptures were due to gunshot wounds and 58 were secondary to a pelvic fracture. There were 58 repairs done by the perineal approach and 5 required an abdominal perineal approach. Surgical complications included 2 (3%) rectal injuries, 3 (5%) repeat strictures that required reoperation and 20 (32%) repeat strictures that required dilation or visual internal urethrotomy. By 1 year after surgery all patients had a patent urethra and did not require further treatment. At 1 year 43 (72%) patients voided normally, 5 (8.3%) were areflexic and performed self-catheterization, 5 (8.3%) had urge incontinence and 5 (8.3%) had mild stress incontinence requiring no treatment. Moderate stress incontinence responded to imipramine in 1 case and collagen injection in 1. Of the patients who were potent preoperatively 31 (52%) remained potent postoperatively. Of the 29 (48%) patients who were impotent preoperatively and immediately postoperatively 9 regained potency at 1 year. However, at 1 year, the quality of erections of the 40 potent men was normal in only 22 (37%) and fair to poor in 18 (30%). The 1-stage delayed bulboprostatic anastomotic urethroplasty has a good long-term result with little morbidity for treatment of posterior urethral ruptures in men.

Open urethroplasty versus endoscopic urethrotomy--clarifying the management of men with recurrent urethral stricture (the OPEN trial): study protocol for a randomised controlled trial.

PubMed

Stephenson, Rachel; Carnell, Sonya; Johnson, Nicola; Brown, Robbie; Wilkinson, Jennifer; Mundy, Anthony; Payne, Steven; Watkin, Nick; N'Dow, James; Sinclair, Andrew; Rees, Rowland; Barclay, Stewart; Cook, Jonathan A; Goulao, Beatriz; MacLennan, Graeme; McPherson, Gladys; Jackson, Matthew; Rapley, Tim; Shen, Jing; Vale, Luke; Norrie, John; McColl, Elaine; Pickard, Robert

2015-12-30

Urethral stricture is a common cause of difficulty passing urine in men with prevalence of 0.5 %; about 62,000 men in the UK. The stricture is usually sited in the bulbar part of the urethra causing symptoms such as reduced urine flow. Initial treatment is typically by endoscopic urethrotomy but recurrence occurs in about 60% of men within 2 years. The best treatment for men with recurrent bulbar stricture is uncertain. Repeat endoscopic urethrotomy opens the narrowing but it usually scars up again within 2 years requiring repeated procedures. The alternative of open urethroplasty involves surgically reconstructing the urethra, which may need an oral mucosal graft. It is a specialist procedure with a longer recovery period but may give lower risk of recurrence. In the absence of firm evidence as to which is best, individual men have to trade off the invasiveness and possible benefit of each option. Their preference will be influenced by individual social circumstances, availability of local expertise and clinician guidance. The open urethroplasty versus endoscopic urethrotomy (OPEN) trial aims to better guide the choice of treatment for men with recurrent urethral strictures by comparing benefit over 2 years in terms of symptom control and need for further treatment. OPEN is a pragmatic, UK multicentre, randomised trial. Men with recurrent bulbar urethral strictures (at least one previous treatment) will be randomised to undergo endoscopic urethrotomy or open urethroplasty. Participants will be followed for 24 months after randomisation, measuring symptoms, flow rate, the need for re-intervention, health-related quality of life, and costs. The primary clinical outcome is the difference in symptom control over 24 months measured by the area under the curve (AUC) of a validated score. The trial has been powered at 90% with a type I error rate of 5% to detect a 0.1 difference in AUC measured on a 0-1 scale. The analysis will be based on all participants as randomised (intention-to-treat). The primary economic outcome is the incremental cost per quality-adjusted life year. A qualitative study will assess willingness to be randomised and hence ability to recruit to the trial. The OPEN Trial seeks to clarify relative benefit of the current options for surgical treatment of recurrent bulbar urethral stricture which differ in their invasiveness and resources required. Our feasibility study identified that participation would be limited by patient preference and differing recruitment styles of general and specialist urologists. We formulated and implemented effective strategies to address these issues in particular by inviting participation as close as possible to diagnosis. In addition re-calculation of sample size as recruitment progressed allowed more efficient design given the limited target population and funding constraints. Recruitment is now to target. ISRCTN98009168 Date of registration: 29 November 2012.

Ventral inlay buccal mucosal graft urethroplasty: a novel surgical technique for the management of urethral stricture disease.

PubMed

Kovell, Robert Caleb; Terlecki, Ryan Patrick

2015-02-01

To describe the novel technique of ventral inlay substitution urethroplasty for the management of male anterior urethral stricture disease. A 58-year-old gentleman with multifocal bulbar stricture disease measuring 7 cm in length was treated using a ventral inlay substitution urethroplasty. A dorsal urethrotomy was created, and the ventral urethral plated was incised. The edges of the urethral plate were mobilized without violation of the ventral corpus spongiosum. A buccal mucosa graft was harvested and affixed as a ventral inlay to augment the caliber of the urethra. The dorsal urethrotomy was closed over a foley catheter. No intraoperative or postoperative complications occurred. Postoperative imaging demonstrated a widely patent urethra. After three years of follow-up, the patient continues to do well with no voiding complaints and low postvoid residuals. Ventral inlay substitution urethroplasty appears to be a safe and feasible technique for the management of bulbar urethral strictures.

SIU/ICUD Consultation on Urethral Strictures: Posterior urethral stenosis after treatment of prostate cancer.

PubMed

Herschorn, Sender; Elliott, Sean; Coburn, Michael; Wessells, Hunter; Zinman, Leonard

2014-03-01

Posterior urethral stenosis can result from radical prostatectomy in approximately 5%-10% of patients (range 1.4%-29%). Similarly, 4%-9% of men after brachytherapy and 1%-13% after external beam radiotherapy will develop stenosis. The rate will be greater after combination therapy and can exceed 40% after salvage radical prostatectomy. Although postradical prostatectomy stenoses mostly develop within 2 years, postradiotherapy stenoses take longer to appear. Many result in storage and voiding symptoms and can be associated with incontinence. The evaluation consists of a workup similar to that for lower urinary tract symptoms, with additional testing to rule out recurrent or persistent prostate cancer. Treatment is usually initiated with an endoscopic approach commonly involving dilation, visual urethrotomy with or without laser treatment, and, possibly, UroLume stent placement. Open surgical urethroplasty has been reported, as well as urinary diversion for recalcitrant stenosis. A proposed algorithm illustrating a graded approach has been provided. Copyright © 2014 Elsevier Inc. All rights reserved.

Above and below delayed endoscopic treatment of traumatic posterior urethral disruptions.

PubMed

Quint, H J; Stanisic, T H

1993-03-01

Between 1982 and 1990, 10 men with posterior urethral obliterations associated with pelvic fracture were managed with delayed above and below endoscopic reconstruction. After a mean of 43 months (range 7 to 108) of followup, all 10 men void with a peak flow rate of 12 ml. per second or greater and/or have a urethral caliber of 20F or greater. Concomitant prostatic hypertrophy somewhat compromises micturition in 4 older men. Nine patients are totally continent and 1 has mild stress incontinence. Five men who were potent after injury remain so after reconstruction. Of the 10 patients 6 required subsequent visual urethrotomy and/or scar resections, generally as outpatient or short stay procedures. In most instances voiding stabilized within 1 year, and interventions after this interval were unusual and generally trivial. We compare our experience with the results of others using a similar delayed endoscopic approach and conclude that this is a satisfactory method of managing traumatic posterior urethral obliterations, resulting in satisfactory voiding, continence and potency preservation.

Urethroplasty: a geographic disparity in care.

PubMed

Burks, Frank N; Salmon, Scott A; Smith, Aaron C; Santucci, Richard A

2012-06-01

Urethroplasty is the gold standard for urethral strictures but its geographic prevalence throughout the United States is unknown. We analyzed where and how often urethroplasty was being performed in the United States compared to other treatment modalities for urethral stricture. De-identified case logs from the American Board of Urology were collected from certifying/recertifying urologists from 2004 to 2009. Results were categorized by ZIP codes to determine the geographic distribution. Case logs from 3,877 urologists (2,533 recertifying and 1,344 certifying) were reviewed including 1,836 urethroplasties, 13,080 urethrotomies and 19,564 urethral dilations. The proportion of urethroplasty varied widely among states (range 0% to 17%). The ratio of urethroplasty-to-urethrotomy/dilation also varied widely from state to state, but overall 1 urethroplasty was performed for every 17 urethrotomies or dilations performed. Certifying urologists were 3 times as likely to perform urethroplasty as recertifying urologists (12% vs 4%, respectively, p<0.05). Urethroplasties were performed more commonly in states with residency programs (mean 5% vs 3%). Some states reported no urethroplasties during the observation period (Vermont, North Dakota, South Dakota, Maine and West Virginia). To our knowledge this is the first report on the geographic distribution of urethroplasty for urethral stricture disease. There are large variations in the rates of urethroplasty performed throughout the United States, indicating a disparity of care, especially for those regions in which few or no urethroplasties were reported. This disparity may decrease with time as younger certifying urologists are performing 3 times as many urethroplasties as older recertifying urologists. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

URETHROPLASTY FOR COMPLICATED ANTERIOR URETHRAL STRICTURES.

PubMed

Aoki, Katsuya; Hori, Shunta; Morizawa, Yosuke; Nakai, Yasushi; Miyake, Makito; Anai, Satoshi; Torimoto, Kazumasa; Yoneda, Tatsuo; Tanaka, Nobumichi; Yoshida, Katsunori; Fujimoto, Kiyohide

2016-01-01

(Objectives) To compare efficacy and outcome of urethroplasty for complicated anterior urethral strictures. (Methods) Twelve patients, included 3 boys, with anterior urethral stricture underwent urethroplasty after the failure of either urethral dilatation or internal urethrotomy. We evaluated pre- and post-operative Q max and surgical outcome. (Results) Four patients were treated with end-to-end anastomosis, included a case of bulbar urethral elongation simultaneously, one patient was treated with augmented anastomotic urethroplasty, three patients were treated with onlay urethroplasty with prepucial flap, one patient was treated with tubed urethroplasty with prepucial flap (Ducket procedure) and three patients were treated with onlay urethroplasty with buccal mucosal graft. Postoperative Qmax improved in all patients without major complications and recurrence during follow-up periods ranging from 17 to 102 months (mean 55 months). (Conclusions) Urethroplasty is an effective therapeutic procedure for complicated anterior urethral stricture.

Single stage circumferential lingual mucosal graft urethroplasty in near obliterative bulbar urethra stricture: A novel technique.

PubMed

Sharma, Umesh; Yadav, Sher Singh; Tomar, Vinay; Garg, Amit

2016-01-01

This is a prospective study of the use and efficacy of a novel technique of circumferential tubularised lingual mucosal graft (LMG) in obliterative and near obliterative bulbar urethral stricture of >2 cm where excisional and augmented anastomotic urethroplasty are not feasible. The stenotic urethral segment was opened dorsally in midline and fibrosed urethra was excised taking care to preserve the healthy spongiosum tissue. LMG (av. Length 3 cm) was placed from one end of corporal body towards spongy tissue in a circumferential manner. Another LMG was placed in similar manner to deal with longer stricture. The urethra was tubularised over 14 Fr silicone catheter. A total of 12 men, of mean age 47 years underwent this procedure. The mean follow up period was 11 months starting from July 2014 till manuscript submission. Follow up included voiding cystourethrogram at 3 weeks, cystoscopy at 3 months (one patient didn't turned up) and subsequent follow up. Mean stricture length was 4.66 cm (range, 3-8.5 cm) and mean operative time was 195 min. (range, 160 to 200 min.). The technique was successful (normal voiding with no need for any post-operative procedure) in 11(91.6%) patients. One patient developed early recurrence at 4 month of surgery and had anastomotic stricture which was successfully managed by direct visual internal urethrotomy. Single stage circumferential tubularised graft urethroplasty is an excellent technique for strictures that include segments of obliterative and near obliterative diseased urethra. It provide a wider neourethra than patch graft urethroplasty.

In-vivo laser induced urethral stricture animal model for investigating the potential of LDR-brachytherapy

NASA Astrophysics Data System (ADS)

Sroka, Ronald; Lellig, Katja; Bader, Markus; Stief, Christian; Weidlich, Patrick; Wechsel, G.; Assmann, Walter; Becker, R.; Fedorova, O.; Khoder, Wael

2015-02-01

Purpose: Treatment of urethral strictures is a major challenge in urology. For investigation of different treatment methods an animal model was developed by reproducible induction of urethral strictures in rabbits to mimic the human clinical situation. By means of this model the potential of endoluminal LDR brachytherapy using β-irradiation as prophylaxis of recurrent urethral strictures investigated. Material and Methods: A circumferential urethral stricture was induced by energy deposition using laser light application (wavelength λ=1470 nm, 10 W, 10 s, applied energy 100 J) in the posterior urethra of anaesthetized New Zealand White male rabbits. The radial light emitting fiber was introduced by means of a children resectoscope (14F). The grade of urethral stricture was evaluated in 18 rabbits using videourethroscopy and urethrography at day 28 after stricture induction. An innovative catheter was developed based on a β-irradiation emitting foil containing 32P, which was wrapped around the application system. Two main groups (each n=18) were separated. The "internal urethrotomy group" received after 28days of stricture induction immediately after surgical urethrotomy of the stricture the radioactive catheter for one week in a randomized, controlled and blinded manner. There were 3 subgroups with 6 animals each receiving 0 Gy, 15 Gy and 30 Gy. In contrast animals from the "De Nuovo group" received directly after the stricture induction (day 0) the radioactive catheter also for the duration of one week divided into the same dose subgroups. In order to determine the radiation tolerance of the urethral mucosa, additional animals without any stricture induction received a radioactive catheter applying a total dose of 30 Gy (n=2) and 15 Gy (n=1). Cystourethrography and endoscopic examination of urethra were performed on all operation days for monitoring treatment progress. Based on these investigation a classification of the stricture size was performed and documented for correlation. At further 28 days after catheter removal the animals were euthanasized and the urethra tissue was harvested. Histological examination of tissue with assessment of radiation damage, fibrotic and inflammatory changes were performed. After deblinding histological finding were correlated with the applied dose. Results: All animals developed a stricture, while 15/18 (83,3%) showed a significant, high grade stricture with more than 90% lumen narrowing. Histopathological examination including evaluation of urethral inflammation, fibrosis and collagen content were investigated in additional 6 rabbits confirming the former findings. No rabbits died prematurely during the study. The experiments showed that the procedure of the application of radioactive catheter was safe without any problems in contamination and protection handling. The combination of internal urethrotomy and LDR-brachytherapy results in a stricture free rate of 66.7% in the 15-Gy group, compared with only 33.3% among animals from the 0- and 30-Gy groups. Furthermore histological classification of inflammation and fibrosis of 0 Gy and 15 Gy showed similar extent. Conclusion: This new method of laser induced urethral stricture was very efficient and showed a high reproducibility, thus being useful for studying stenosis treatments. The experiments showed that application of local β-irradiation by means of radioactive catheters modulated the stenosis development. This kind of LDR-brachytherapy shows potential for prophylaxis of urethral stricture. As this was an animal pilot experiment a clinical dose response study is needed.

Holmium laser lithotripsy of bladder calculi

NASA Astrophysics Data System (ADS)

Beaghler, Marc A.; Poon, Michael W.

1998-07-01

Although the overall incidence of bladder calculi has been decreasing, it is still a significant disease affecting adults and children. Prior treatment options have included open cystolitholapaxy, blind lithotripsy, extracorporeal shock wave lithotripsy, and visual lithotripsy with ultrasonic or electrohydraulic probes. The holmium laser has been found to be extremely effective in the treatment of upper tract calculi. This technology has also been applied to the treatment of bladder calculi. We report our experience with the holmium laser in the treatment of bladder calculi. Twenty- five patients over a year and a half had their bladder calculi treated with the Holmium laser. This study was retrospective in nature. Patient demographics, stone burden, and intraoperative and post-operative complications were noted. The mean stone burden was 31 mm with a range of 10 to 60 mm. Preoperative diagnosis was made with either an ultrasound, plain film of the abdomen or intravenous pyelogram. Cystoscopy was then performed to confirm the presence and determine the size of the stone. The patients were then taken to the operating room and given a regional or general anesthetic. A rigid cystoscope was placed into the bladder and the bladder stone was then vaporized using the holmium laser. Remaining fragments were washed out. Adjunctive procedures were performed on 10 patients. These included transurethral resection of the prostate, transurethral incision of the prostate, optic internal urethrotomy, and incision of ureteroceles. No major complications occurred and all patients were rendered stone free. We conclude that the Holmium laser is an effective and safe modality for the treatment of bladder calculi. It was able to vaporize all bladder calculi and provides a single modality of treating other associated genitourinary pathology.

Voiding and erectile function after delayed one-stage repair of posterior urethral disruptions in 50 men with a fractured pelvis.

PubMed

Corriere, J N; Rudy, D C; Benson, G S

1994-10-01

We evaluated 50 men who suffered a total disruption of the posterior urethra in conjunction with a fractured pelvis. The urethral disruption was treated with immediate placement of a suprapubic cystostomy and delayed one-stage urethroplasty. Subsequently, 15 required at least one visual urethrotomy and three underwent one urethral dilatation. All 50 now have a patent urethra and 38 (76%) void normally and are continent. Five have an areflexic bladder secondary to the injury and intermittently catheterize themselves but are continent. Three patients have mild urge incontinence and three mild stress incontinence, not requiring treatment or protection. One patient with an open bladder neck has moderate stress incontinence which has responded to imipramine therapy. Impotence was present both preoperatively and postoperatively in 24 (48%) of the patients but by one year only 16 (32%) of them were still not having erections. Eighteen patients (36%) claim to have erections equal to their pre-injury quality. However, 16 (32%) of the patients, although potent and able to have intercourse, have less than optimal erections.

Posterior urethral stricture repair following trauma and pelvic fracture.

PubMed

Rios, Emilio; Martinez-Piñeiro, Luis; Álvarez-Maestro, Mario

2014-01-01

Posterior urethral injuries typically arise in the context of a pelvic fracture.The correct and appropriate initial treatment of associated urethral rupture is critical to the proper healing of the injury. In this paper, we provide a comprehensive review of the literature with special emphasis on the various treatments available: open or endoscopic primary realignment, immediate or delayed urethroplasty after suprapubic cystostomy, and delayed optical urethrotomy.

Endoscopic-assisted disruption of urinary calculi using a holmium:YAG laser in standing horses.

PubMed

Judy, Carter E; Galuppo, Larry D

2002-01-01

To describe a technique for endoscope-assisted disruption and removal of urinary calculi using a holmium:YAG laser in sedated, standing horses. Retrospective study. Six horses with urinary calculi. A holmium:YAG laser was used to disrupt naturally occurring urinary calculi in horses (4 geldings, 1 stallion, 1 mare). Ischial urethrotomy was performed in male horses to provide a portal for the endoscope and laser fiber. Calculus fragments were removed by a combination of lavage, transendoscopic basket snare removal, forceps, and digital manipulation. Ischial urethrotomies healed by second intention. Follow-up was obtained by recheck examination and telephone interview of owners. No major operative or postoperative complications occurred. Two calculi (1 stallion and 1 mare) were fragmented by a combination of laser ablation and manual disruption with a lithotrite. Postoperative dysuria occurred in the mare, but resolved after 1 month. Mean (+/- SD) follow-up was 306 +/- 149 days; no other complications were reported. Calcium carbonate urinary calculi (up to 15 cm in diameter) in horses can be effectively fragmented with a holmium:YAG laser. It is not known if this technique would be completely effective for larger calculi or extremely dense calculi. Calculus disruption by an endoscopically assisted holmium:YAG laser offers a minimally invasive method that can be performed in standing horses and that minimizes patient risk. Copyright 2002 by The American College of Veterinary Surgeons

[Urethral stricture rate after prostate cancer radiotherapy : Five-year data of a certified prostate cancer center].

PubMed

Kranz, J; Maurer, G; Maurer, U; Deserno, O; Schulte, S; Steffens, J

2017-03-01

A urethral stricture is a scar of the urethral epithelium which can cause obstructive voiding dysfunction with consequential damage of the upper urinary tract. Almost 45% of all strictures are iatrogenic; they develop in 2-9% of patients after radical prostatectomy, but can also occur after prostate cancer radiotherapy. This study provides 5‑year data of a certified prostate cancer center (PKZ) in terms of urethral strictures. Between 01/2008 and 12/2012 a total of 519 men were irradiated for prostate cancer (LDR and HDR brachytherapy as well as external beam radiation). The entire cohort was followed-up prospectively according to a standardized protocol (by type of irradiation). Short segment urethral strictures were treated by urethrotomy, recurrent and long segment stenosis with buccal mucosa urethroplasty. A total of 18 of 519 (3.4%) patients developed a urethral stricture post-therapeutically, which recurred in 66% of cases after the first operative treatment. The largest risk for developing a urethral stricture is attributed to the HDR brachytherapy (8.9%). Urethral strictures after prostate cancer radiotherapy should be diagnosed and treated in time for long-term preservation of renal function. The rate of radiogenic urethral strictures (3.4%) is equivalent to those after radical prostatectomy. Due to a high rate of recurrences, urethrotomy has a limited importance after irradiation.

Dorsal inlay buccal mucosal graft (Asopa) urethroplasty for anterior urethral stricture.

PubMed

Marshall, Stephen D; Raup, Valary T; Brandes, Steven B

2015-02-01

Asopa described the inlay of a graft into Snodgrass's longitudinal urethral plate incision using a ventral sagittal urethrotomy approach in 2001. He claimed that this technique was easier to perform and led to less tissue ischemia due to no need for mobilization of the urethra. This approach has subsequently been popularized among reconstructive urologists as the dorsal inlay urethroplasty or Asopa technique. Depending on the location of the stricture, either a subcoronal circumferential incision is made for penile strictures, or a midline perineal incision is made for bulbar strictures. Other approaches for penile urethral strictures include the non-circumferential penile incisional approach and a penoscrotal approach. We generally prefer the circumferential degloving approach for penile urethral strictures. The penis is de-gloved and the urethra is split ventrally to exposure the stricture. It is then deepened to include the full thickness of the dorsal urethra. The dorsal surface is made raw and grafts are fixed on the urethral surface. Quilting sutures are placed to further anchor the graft. A Foley catheter is placed and the urethra is retubularized in two layers with special attention to the staggering of suture lines. The skin incision is then closed in layers. We have found that it is best to perform an Asopa urethroplasty when the urethral plate is ≥1 cm in width. The key to when to use the dorsal inlay technique all depends on the width of the urethral plate once the urethrotomy is performed, stricture etiology, and stricture location (penile vs. bulb).

Acquired urethral obstruction in New World camelids: 34 cases (1995-2008).

PubMed

Duesterdieck-Zellmer, K F; Van Metre, D C; Cardenas, A; Cebra, C K

2014-08-01

Document the clinical features, short- and long-term outcomes and prognostic factors in New World camelids with acquired urethral obstruction. Retrospective case study. Case data from medical records of 34 New World camelids presenting with acquired urethral obstruction were collected and follow-up information on discharged patients was obtained. Associations with short- and long-term survival were evaluated using Wilcoxon rank-sum tests, exact-logistic regressions and Kaplan-Meier survival curves. Of the 34 New World camelids 23 were intact males and 11 were castrated; 4 animals were euthanased upon presentation, 7 were treated medically and 23 surgically, including urethrotomy, bladder marsupialisation, tube cystostomy alone or combined with urethrotomy, urethrostomy or penile reefing. Necrosis of the distal penis was found in 4 animals and all were short-term non-survivors. Short-term survival for surgical cases was 65%, and 57% for medical cases. Incomplete urethral obstruction at admission and surgical treatment were associated with increased odds of short-term survival. Of 14 records available for long-term follow-up, 6 animals were alive and 8 were dead (median follow-up 4.5 years, median survival time 2.5 years). Recurrence of urethral obstruction was associated with long-term non-survival. Surgically treated New World camelids with incomplete urethral obstruction have the best odds of short-term survival and those with recurrence of urethral obstruction have a poor prognosis for long-term survival. © 2014 Australian Veterinary Association.

Advances in urethral stricture management

PubMed Central

Gallegos, Maxx A.; Santucci, Richard A.

2016-01-01

Urethral stricture/stenosis is a narrowing of the urethral lumen. These conditions greatly impact the health and quality of life of patients. Management of urethral strictures/stenosis is complex and requires careful evaluation. The treatment options for urethral stricture vary in their success rates. Urethral dilation and internal urethrotomy are the most commonly performed procedures but carry the lowest chance for long-term success (0–9%). Urethroplasty has a much higher chance of success (85–90%) and is considered the gold-standard treatment. The most common urethroplasty techniques are excision and primary anastomosis and graft onlay urethroplasty. Anastomotic urethroplasty and graft urethroplasty have similar long-term success rates, although long-term data have yet to confirm equal efficacy. Anastomotic urethroplasty may have higher rates of sexual dysfunction. Posterior urethral stenosis is typically caused by previous urologic surgery. It is treated endoscopically with radial incisions. The use of mitomycin C may decrease recurrence. An exciting area of research is tissue engineering and scar modulation to augment stricture treatment. These include the use of acellular matrices or tissue-engineered buccal mucosa to produce grafting material for urethroplasty. Other experimental strategies aim to prevent scar formation altogether. PMID:28105329

Posttraumatic posterior urethral strictures in children: a 20-year experience.

PubMed

Koraitim, M M

1997-02-01

We attempted to identify the particular features of strictures complicating pelvic fracture urethral injuries in children. A total of 68 boys 3 to 15 years old who had sustained pelvic fracture urethral disruption underwent 78 urethroplasties performed by bulboprostatic anastomosis through the perineum in 42, transpubically in 23 and by 2-stage urethroscrotal inlay in 13. Perineal and transurethral urethroplasty was successful in 93 and 91% of cases respectively. There was a 54% failure rate after urethroscrotal inlay. Urethral strictures were most commonly associated with Malgaigne's fracture (35% of cases) and straddle fracture with or without diastasis of the sacroiliac joint (26%). Strictures were almost invariably inferior to the verumontanum with prostatic displacement in 44% of cases. Length of the strictured segment may be overestimated or underestimated on urethrography as a result of incomplete filling of the prostatic urethra or a urinoma cavity connected with the proximal segment, respectively. Perineal or transpubic bulboprostatic anastomosis is the best treatment for posttraumatic strictures, while internal urethrotomy should be avoided since it may compromise the chance of subsequent anastomotic urethroplasty. Repair of associated bladder neck incompetence may be deferred until the resumption of urethral voiding after urethroplasty, when incontinence can be documented.

Urethral Strictures and Stenoses Caused by Prostate Therapy

PubMed Central

Chen, Mang L.; Correa, Andres F.; Santucci, Richard A.

2016-01-01

The number of patients with prostate cancer and benign prostatic hyperplasia is on the rise. As a result, the volume of prostate treatment and treatment-related complications is also increasing. Urethral strictures and stenoses are relatively common complications that require individualized management based on the length and location of the obstruction, and the patient’s overall health, and goals of care. In general, less invasive options such as dilation and urethrotomy are preferred as first-line therapy, followed by more invasive substitution, flap, and anastomotic urethroplasty. PMID:27601967

Urethroplasty after Urethral Urolume Stent: an International Multicenter Experience.

PubMed

Angulo, Javier C; Kulkarni, Sanjay; Pankaj, Joshi; Nikolavsky, Dmitriy; Suarez, Pedro; Belinky, Javier; Virasoro, Ramón; DeLong, Jessica; Martins, Francisco E; Lumen, Nicolaas; Giudice, Carlos; Suárez, Oscar A; Menéndez, Nicolás; Capiel, Leandro; López-Alvarado, Damian; Ramirez, Erick A; Venkatesan, Krishnan; Husainat, Maha M; Esquinas, Cristina; Arance, Ignacio; Gómez, Reynaldo; Santucci, Richard

2018-05-08

To evaluate the outcomes and factors affecting success of urethroplasty in patients with stricture recurrence after Urolume® urethral stent. Retrospective international multicenter study on patients treated with urethral reconstruction after Urolume® stent. Stricture and stent length, time between urethral stent insertion and urethroplasty, age, mode of stent retrieval, type of urethroplasty, complications and baseline and post-urethroplasty voiding parameters were analyzed. Successful outcome was defined as standard voiding, without need of any postoperative adjunctive procedure. Sixty-three patients were included. Stent was removed at urethroplasty in 61 patients. Reconstruction technique was excision and primary anastomosis in 14(22.2%), dorsal onlay buccal mucosa graft (BMG) 9(14.3%), ventral onlay BMG 6(9.5%), dorso-lateral onlay BMG 9(14.3%), ventral onlay plus dorsal inlay BMG 3(4.8%), augmented anastomosis 5(7.9%), pedicled flap urethroplasty 6(9.5%), 2-stage procedure 4(6.4%) and perineal urethrostomy 7(11.1%). Success rate was 81% at a mean 59.7+63.4months. Dilatation and/or internal urethrotomy was performed in 10(15.9%), redo-urethroplasty in 5(7.9%). Total IPSS, QoL, Qmax and PVR significantly improved (p<.0001). Complications occurred in 8(12.7%), all Clavien-Dindo <2. Disease-free survival rate after reconstruction was 88.1%,79.5% and 76.7% at 1,3 and 5-years respectively. Explant of individual strands followed by onlay BMG is the most common approach and was significantly advantageous over the other techniques (p=.018). Urethroplasty in patients with Urolume® urethral stents is a viable option of reconstruction with a high success rate and very acceptable complication rate. Numerous techniques are viable, however, urethral preservation, tine-by-tine stent extraction and use of BMG augmentation produced significantly better outcomes. Copyright © 2018 Elsevier Inc. All rights reserved.

Buccal mucosal urethroplasty for balanitis xerotica obliterans related urethral strictures: the outcome of 1 and 2-stage techniques.

PubMed

Dubey, Deepak; Sehgal, Anand; Srivastava, Aneesh; Mandhani, Anil; Kapoor, Rakesh; Kumar, Anant

2005-02-01

Balanitis xerotica obliterans (BXO) related strictures are complex and generally managed by 2-staged urethroplasty. We present our results with 1-stage dorsal onlay and 2-stage buccal mucosal urethroplasty for such strictures. Between January 2000 and April 2004, 39 patients underwent buccal mucosal urethroplasty for BXO related anterior urethral strictures. The 25 patients with a salvageable urethral plate (group 1) were treated with 1-stage dorsal onlay urethroplasty using a cosmetic incision. The 14 patients with a severely scarred urethral plate, focally dense segments or active infection (group 2) underwent 2-stage urethroplasty. Outcomes in terms of cosmetic appearance, stricture recurrence and complications in the 2 groups were assessed. At a mean followup of 32.5 months (range 3 to 52) 3 patients (12%) in group 1 had recurrent stricture, of which 2 and 1 were treated with optical urethrotomy and urethral dilation, respectively. All patients had a normal slit-like meatus and none had chordee or erectile dysfunction. Four group 2 patients (28.6%) required stomal revision and 2 had glans cleft narrowing after stage 1 urethroplasty. Following stage 2, 3 patients had recurrent stricture, of whom 2 were treated with optical urethrotomy and 1 underwent repeat urethroplasty. In BXO related strictures with a viable urethral plate 1-stage dorsal onlay buccal mucosal urethroplasty provides excellent intermediate term results. The cosmetic incision described provides a normal, wide caliber, slit-like glans. Two-stage procedures provide satisfactory outcomes but they are associated with a higher revision rate.

Dorsal inlay buccal mucosal graft (Asopa) urethroplasty for anterior urethral stricture

PubMed Central

Marshall, Stephen D.; Raup, Valary T.

2015-01-01

Asopa described the inlay of a graft into Snodgrass’s longitudinal urethral plate incision using a ventral sagittal urethrotomy approach in 2001. He claimed that this technique was easier to perform and led to less tissue ischemia due to no need for mobilization of the urethra. This approach has subsequently been popularized among reconstructive urologists as the dorsal inlay urethroplasty or Asopa technique. Depending on the location of the stricture, either a subcoronal circumferential incision is made for penile strictures, or a midline perineal incision is made for bulbar strictures. Other approaches for penile urethral strictures include the non-circumferential penile incisional approach and a penoscrotal approach. We generally prefer the circumferential degloving approach for penile urethral strictures. The penis is de-gloved and the urethra is split ventrally to exposure the stricture. It is then deepened to include the full thickness of the dorsal urethra. The dorsal surface is made raw and grafts are fixed on the urethral surface. Quilting sutures are placed to further anchor the graft. A Foley catheter is placed and the urethra is retubularized in two layers with special attention to the staggering of suture lines. The skin incision is then closed in layers. We have found that it is best to perform an Asopa urethroplasty when the urethral plate is ≥1 cm in width. The key to when to use the dorsal inlay technique all depends on the width of the urethral plate once the urethrotomy is performed, stricture etiology, and stricture location (penile vs. bulb). PMID:26816804

Buccal mucosal graft urethroplasty in men-risk factors for recurrence and complications: a third referral centre experience in anterior urethroplasty using buccal mucosal graft.

PubMed

Spilotros, Marco; Sihra, Neha; Malde, Sachin; Pakzad, Mahreen H; Hamid, Rizwan; Ockrim, Jeremy L; Greenwell, Tamsin J

2017-06-01

Urethral stricture disease is a challenging condition to treat and several approaches including direct visual internal urethrotomy (DVIU) and anastomotic or augmentation urethroplasties based on the use of flaps and graft have been reported. The aim of this study is to determine risk factors for stricture recurrence and complications in patients having buccal mucosal graft (BMG) urethroplasty for anterior urethral stricture under a single surgeon in a third referral centre in UK. We conducted a retrospective review of a prospectively gathered database of 128 patients having various forms of BMG urethroplasty between 2001 and 2015. Success and failure in terms of stricture recurrence, patient demographics, stricture aetiology and anatomy, and the adverse outcomes of: post-micturition dribbling (PMD), erectile dysfunction (ED) >12 months and complications were recorded in order to determine risk factors for recurrent stricture and complications. The mean age of all patients was 42.8 years (range, 16-74 years). Average follow-up was 45 months (range, 3-159 months). The total re-stricture rate was 19% (24 men). PMD was reported in 16% (n=20) and ED in 12.5% (n=16). All ED was none organic and responded to oral PDE5 inhibitor treatment. Post-operative complications were reported in 16 patients (12.5%). The most frequent complications recorded were urinary fistula (n=4; 3.1%), graft contracture (n=4; 3.1%) and graft failure (n=4; 3.1%), all reported after penile urethroplasty. Univariate analysis indicated that age at surgery, stricture length, site and aetiology were all significant risk factors for stricture recurrence. On multivariate analysis penile site was the only significant independent variable for restricture. BMG urethroplasty represents a reliable therapeutic option for patient with urethral strictures with a success rate of 81% at 45 months of follow-up. Complications are more common in complex stricture of the penile urethra. On multivariate analysis penile site was the only significant independent variable for re-stricture.

Buccal mucosal graft urethroplasty in men—risk factors for recurrence and complications: a third referral centre experience in anterior urethroplasty using buccal mucosal graft

PubMed Central

Sihra, Neha; Malde, Sachin; Pakzad, Mahreen H.; Hamid, Rizwan; Ockrim, Jeremy L.; Greenwell, Tamsin J.

2017-01-01

Background Urethral stricture disease is a challenging condition to treat and several approaches including direct visual internal urethrotomy (DVIU) and anastomotic or augmentation urethroplasties based on the use of flaps and graft have been reported. The aim of this study is to determine risk factors for stricture recurrence and complications in patients having buccal mucosal graft (BMG) urethroplasty for anterior urethral stricture under a single surgeon in a third referral centre in UK. Methods We conducted a retrospective review of a prospectively gathered database of 128 patients having various forms of BMG urethroplasty between 2001 and 2015. Success and failure in terms of stricture recurrence, patient demographics, stricture aetiology and anatomy, and the adverse outcomes of: post-micturition dribbling (PMD), erectile dysfunction (ED) >12 months and complications were recorded in order to determine risk factors for recurrent stricture and complications. Results The mean age of all patients was 42.8 years (range, 16–74 years). Average follow-up was 45 months (range, 3–159 months). The total re-stricture rate was 19% (24 men). PMD was reported in 16% (n=20) and ED in 12.5% (n=16). All ED was none organic and responded to oral PDE5 inhibitor treatment. Post-operative complications were reported in 16 patients (12.5%). The most frequent complications recorded were urinary fistula (n=4; 3.1%), graft contracture (n=4; 3.1%) and graft failure (n=4; 3.1%), all reported after penile urethroplasty. Univariate analysis indicated that age at surgery, stricture length, site and aetiology were all significant risk factors for stricture recurrence. On multivariate analysis penile site was the only significant independent variable for restricture. Conclusions BMG urethroplasty represents a reliable therapeutic option for patient with urethral strictures with a success rate of 81% at 45 months of follow-up. Complications are more common in complex stricture of the penile urethra. On multivariate analysis penile site was the only significant independent variable for re-stricture. PMID:28725593

An improved delivery system for bladder irrigation

PubMed Central

Moslemi, Mohammad K; Rajaei, Mojtaba

2010-01-01

Introduction Occasionally, urologists may see patients requiring temporary bladder irrigation at hospitals without stocks of specialist irrigation apparatus. One option is to transfer the patient to a urology ward, but often there are outstanding medical issues that require continued specialist input. Here, we describe an improved system for delivering temporary bladder irrigation by utilizing readily available components and the novel modification of a sphygmomanometer blub. This option is good for bladder irrigation in patients with moderate or severe gross hematuria due to various causes. Materials and methods In this prospective study from March 2007 to April 2009, we used our new system in eligible cases. In this system, an irrigant bag with 1 L of normal saline was suspended 80 cm above the indwelled 3-way Foley catheter, and its drainage tube was inserted into the irrigant port of the catheter. To increase the flow rate of the irrigant system, we inserted a traditional sphygmomanometer bulb at the top of the irrigant bag. This closed system was used for continuous bladder irrigation (CBI) in patients who underwent open prostatectomy, transurethral resection of the prostate (TURP), or transurethral resection of the bladder (TURB). This high-pressure system is also used for irrigation during cystourethroscopy, internal urethrotomy, and transurethral lithotripsy. Our 831 eligible cases were divided into two groups: group 1 were endourologic cases and group 2 were open prostatectomy, TURP, and TURB cases. The maximum and average flow rates were evaluated. The efficacy of our new system was compared prospectively with the previous traditional system used in 545 cases. Results In group 1, we had clear vision at the time of endourologic procedures. The success rate of this system was 99.5%. In group 2, the incidence of clot retention decreased two fold in comparison to traditional gravity-dependent bladder flow system. These changes were statistically significant (P = 0.001). We did not observe any adverse effects such as bladder perforation due to our high-pressure, high-flow system. Conclusion A pressurized irrigant system has better visualization during endourologic procedures, and prevents clot formation after open prostatectomy, TURP, and TURB without any adverse effects. PMID:20957138

An improved delivery system for bladder irrigation.

PubMed

Moslemi, Mohammad K; Rajaei, Mojtaba

2010-10-05

Occasionally, urologists may see patients requiring temporary bladder irrigation at hospitals without stocks of specialist irrigation apparatus. One option is to transfer the patient to a urology ward, but often there are outstanding medical issues that require continued specialist input. Here, we describe an improved system for delivering temporary bladder irrigation by utilizing readily available components and the novel modification of a sphygmomanometer blub. This option is good for bladder irrigation in patients with moderate or severe gross hematuria due to various causes. In this prospective study from March 2007 to April 2009, we used our new system in eligible cases. In this system, an irrigant bag with 1 L of normal saline was suspended 80 cm above the indwelled 3-way Foley catheter, and its drainage tube was inserted into the irrigant port of the catheter. To increase the flow rate of the irrigant system, we inserted a traditional sphygmomanometer bulb at the top of the irrigant bag. This closed system was used for continuous bladder irrigation (CBI) in patients who underwent open prostatectomy, transurethral resection of the prostate (TURP), or transurethral resection of the bladder (TURB). This high-pressure system is also used for irrigation during cystourethroscopy, internal urethrotomy, and transurethral lithotripsy. Our 831 eligible cases were divided into two groups: group 1 were endourologic cases and group 2 were open prostatectomy, TURP, and TURB cases. The maximum and average flow rates were evaluated. The efficacy of our new system was compared prospectively with the previous traditional system used in 545 cases. In group 1, we had clear vision at the time of endourologic procedures. The success rate of this system was 99.5%. In group 2, the incidence of clot retention decreased two fold in comparison to traditional gravity-dependent bladder flow system. These changes were statistically significant (P = 0.001). We did not observe any adverse effects such as bladder perforation due to our high-pressure, high-flow system. A pressurized irrigant system has better visualization during endourologic procedures, and prevents clot formation after open prostatectomy, TURP, and TURB without any adverse effects.

Increased internal higher-order aberrations as a useful parameter for indication of vitrectomy in three asteroid hyalosis cases

PubMed Central

Yokoyama, Sho; Kojima, Takashi; Kaga, Tatsushi; Ichikawa, Kazuo

2015-01-01

We report three asteroid hyalosis cases in which internal higher-order aberrations (HOAs) were improved concomitant with improved visual symptoms after vitrectomy. Cases 1 and 2 reported severe floaters and glare disability, although their visual acuities were fairly good. Case 3 showed poor visual acuity since this patient also suffered from mild macular degeneration. For these three asteroid hyalosis cases, we were unsure if treatment with vitrectomy could improve visual symptoms. Therefore, we measured internal HOAs with an aberrometer, and found that the internal HOA values in these cases were high. We suspected that internal high HOAs values were associated with visual disturbance, and performed vitrectomy. After the vitrectomy, the internal HOA values in these three asteroid hyalosis cases markedly decreased, and visual symptoms improved. These observations suggested that measurement of internal HOAs may be useful to determine the indication for vitrectomy. PMID:26698200

Increased internal higher-order aberrations as a useful parameter for indication of vitrectomy in three asteroid hyalosis cases.

PubMed

Yokoyama, Sho; Kojima, Takashi; Kaga, Tatsushi; Ichikawa, Kazuo

2015-12-23

We report three asteroid hyalosis cases in which internal higher-order aberrations (HOAs) were improved concomitant with improved visual symptoms after vitrectomy. Cases 1 and 2 reported severe floaters and glare disability, although their visual acuities were fairly good. Case 3 showed poor visual acuity since this patient also suffered from mild macular degeneration. For these three asteroid hyalosis cases, we were unsure if treatment with vitrectomy could improve visual symptoms. Therefore, we measured internal HOAs with an aberrometer, and found that the internal HOA values in these cases were high. We suspected that internal high HOAs values were associated with visual disturbance, and performed vitrectomy. After the vitrectomy, the internal HOA values in these three asteroid hyalosis cases markedly decreased, and visual symptoms improved. These observations suggested that measurement of internal HOAs may be useful to determine the indication for vitrectomy. 2015 BMJ Publishing Group Ltd.

Treatment of Urethral Strictures from Irradiation and Other Nonsurgical Forms of Pelvic Cancer Treatment

PubMed Central

Khourdaji, Iyad; Parke, Jacob; Burks, Frank

2015-01-01

Radiation therapy (RT), external beam radiation therapy (EBRT), brachytherapy (BT), photon beam therapy (PBT), high intensity focused ultrasound (HIFU), and cryotherapy are noninvasive treatment options for pelvic malignancies and prostate cancer. Though effective in treating cancer, urethral stricture disease is an underrecognized and poorly reported sequela of these treatment modalities. Studies estimate the incidence of stricture from BT to be 1.8%, EBRT 1.7%, combined EBRT and BT 5.2%, and cryotherapy 2.5%. Radiation effects on the genitourinary system can manifest early or months to years after treatment with the onus being on the clinician to investigate and rule-out stricture disease as an underlying etiology for lower urinary tract symptoms. Obliterative endarteritis resulting in ischemia and fibrosis of the irradiated tissue complicates treatment strategies, which include urethral dilation, direct-vision internal urethrotomy (DVIU), urethral stents, and urethroplasty. Failure rates for dilation and DVIU are exceedingly high with several studies indicating that urethroplasty is the most definitive and durable treatment modality for patients with radiation-induced stricture disease. However, a detailed discussion should be offered regarding development or worsening of incontinence after treatment with urethroplasty. Further studies are required to assess the nature and treatment of cryotherapy and HIFU-induced strictures. PMID:26494994

Dorsolateral onlay urethroplasty for anterior urethral strictures by a unilateral urethral mobilization approach.

PubMed

Singh, Bhupendra P; Pathak, Hemant R; Andankar, Mukund G

2009-04-01

For management of long segment anterior urethral stricture, dorsal onlay urethroplasty is currently the most favored single-stage procedure. Conventional dorsal onlay urethroplasty requires circumferential mobilization of the urethra, which might cause ischemia of the urethra in addition to chordee. To determine the feasibility and short-term outcomes of applying a dorsolateral free graft to treat anterior urethral stricture by unilateral urethral mobilization through a perineal approach. A prospective study from September 2005 to March 2008 in a tertiary care teaching hospital. Seventeen patients with long or multiple strictures of the anterior urethra were treated by a dorsolateral free buccal mucosa graft. The pendulous urethra was accessed by penile eversion through the perineal wound. The urethra was not separated from the corporal bodies on one side and was only mobilized from the midline on the ventral aspect to beyond the midline on the dorsal aspect. The urethra was opened in the dorsal midline over the stricture. The buccal mucosa graft was secured on the ventral tunica of the corporal bodies. Mean and median. After a follow-up of 12-30 months, one recurrence developed and 1 patient needed an internal urethrotomy. A unilateral urethral mobilization approach for dorsolateral free graft urethroplasty is feasible for panurethral strictures of any length with good short-term success.

[Perineal urethrostomy plus secondary urethroplasty for ultralong urethral stricture: clinical outcomes and influence on the patient's quality of life].

PubMed

Wang, Yong-Quan; Zhang, Heng; Shen, Wen-Hao; Li, Long-Kun; Li, Wei-Bing; Xiong, En-Qing

2012-04-01

To investigate the outcomes of perineal urethrostomy plus secondary urethroplasty for ultralong urethral stricture and assess its influence on the patient's quality of life. We retrospectively analyzed 54 cases of ultralong urethral stricture treated by perineal urethrostomy from 2000 to 2010. The mean age of the patients was 40 years, and the average length of stricture was 6.5 cm. We evaluated the patients'quality of life by questionnaire investigation and the clinical outcomes based on IPSS, Qmax, the necessity of urethral dilation and satisfaction of the patients. The mean Qmax of the 54 patients was (14.0 +/- 4.7) ml/min. Of the 34 cases that underwent secondary urethroplasty, 22 (64.7%) achieved a mean Qmax of (12.0 +/- 3.5) ml/min, 8 (23.5%) needed regular urethral dilatation and 4 (11.8%) received internal urethrotomy because of restenosis. IPSS scores were 5.4 +/- 2.1 and 8.5 +/- 5.8 after perineal urethrostomy and secondary urethroplasty, respectively. Fifty of the total number of patients (92.6%) were satisfied with the results of perineal urethrostomy, and 22 of the 34 (64.7%) with the results of secondary urethroplasty. Perineal urethrostomy plus secondary urethroplasty is safe and effective for ultralong urethral stricture, and affects very little the patient's quality of life.

Adult urethral stricture: practice of Turkish urologists

PubMed Central

Akyuz, Mehmet; Sertkaya, Zulfu; Koca, Orhan; Calıskan, Selahattin; Kutluhan, Musab Ali; Karaman, Muhammet Ihsan

2016-01-01

ABSTRACT Objectives: To evaluate national practice patterns in the treatment of male anterior urethral strictures among Turkish urologists. Materials and Methods: A survey form including 12 questions prepared to determine active Turkish urologists' approach to diagnosis and treatment of the adult urethral stricture (US) were filled out. Based on the survey results, the institutions which 218 urologists work and their years of expertise, methods they used for diagnosis and treatment, whether or not they perform open urethroplasty and timing of open urethroplasty were investigated. Results: Optic internal urethrotomy and dilatation are the most commonly used minimal invasive procedures in treatment of US with the ratios of 93.5% and 63.3% respectively. On the other hand it was seen that urethroplasty was a less commonly used procedure, compared to minimal invasive techniques, with the ratio of 36.7%. Survey results showed us that the number of US cases observed and open urethroplasty procedures performed increases with increasing years of professional experience. Conclusions: As a method demanding special surgical experience and known as a time-consuming and challenging procedure, open urethroplasty will be able to take a greater part in current urological practice with the help of theoretical education and practical courses given by specific centers and experienced authors. PMID:27256189

Foley catheter guide use during midurethral slings: does it make a difference?

PubMed

Miranne, Jeannine Marie; Dominguez, Aurora; Sokol, Andrew Ian; Gutman, Robert Eric; Iglesia, Cheryl Bernadette

2015-06-01

Our objective was to evaluate whether foley catheter guide use decreased the risk of cystotomy and urethrotomy during retropubic midurethral sling placement. This retrospective cohort study included all women undergoing retropubic synthetic midurethral sling placement at a single academic institution between January 2011 and September 2012. Patients were divided into groups based on whether or not the foley catheter guide was used during surgery. The primary outcome was the incidence of cystotomy. A total of 310 patients underwent retropubic midurethral sling placement. The foley catheter guide was used in 76/310 cases (24.5%). The mean age was 57 ± 11 and mean body mass index was 28 ± 7. More patients in the no-guide group had preoperative urgency (70% versus 58%, p = 0.049), anterior prolapse (95% versus 78%, p < 0.0001), and concomitant prolapse surgery (65% versus 51%, p = 0.03). There was no difference in preoperative urgency urinary incontinence, medical comorbidities, previous surgical history, intraoperative time, blood loss, or postoperative voiding dysfunction rates between groups. Fourteen of the 310 patients (4.5%) had cystotomies: 1/76 (1.3%) in the foley catheter guide group and 13/234 (5.6%) in the no-guide group (p = 0.12). No patients had urethrotomies. On multiple logistic regression, there was no difference in the odds of cystotomy between groups after adjusting for previous prolapse and anti-incontinence surgery, concomitant prolapse repair, level of first assistant, and retropubic local anesthesia use (AOR = 0.2 [95% CI 0.02-1.7]). Foley catheter guide use did not decrease the risk of intraoperative lower urinary tract injury during retropubic midurethral sling placement. Larger prospective studies are needed to confirm this finding.

Management for Prostate Cancer Treatment Related Posterior Urethral and Bladder Neck Stenosis With Stents

PubMed Central

Erickson, Bradley A.; McAninch, Jack W.; Eisenberg, Michael L.; Washington, Samuel L.; Breyer, Benjamin N.

2013-01-01

Purpose Prostate cancer treatment has the potential to lead to posterior urethral stricture. These strictures are sometimes recalcitrant to dilation and urethrotomy alone. We present our experience with the Urolume® stent for prostate cancer treatment related stricture. Materials and Methods A total of 38 men with posterior urethral stricture secondary to prostate cancer treatment were treated with Urolume stenting. Stents were placed in all men after aggressive urethrotomy over the entire stricture. A successfully managed stricture was defined as open and stable for greater than 6 months after any necessary secondary procedures. Results The initial success rate was 47%. After a total of 31 secondary procedures in 19 men, including additional stent placement in 8 (18%), the final success rate was 89% at a mean ± SD followup of 2.3 ± 2.5 years. Four cases (11%) in which treatment failed ultimately requiring urinary diversion (3) or salvage prostatectomy (1). Incontinence was noted in 30 men (82%), of whom 19 (63%) received an artificial urinary sphincter a mean of 7.2 ± 2.4 months after the stent. Subanalysis revealed that irradiated men had longer strictures (3.6 vs 2.0 cm, p = 0.003) and a higher post-stent incontinence rate (96% vs 50%, p <0.001) than men who underwent prostatectomy alone but the initial failure rate was similar (54% vs 50%, p = 0.4). Conclusions Urolume stenting is a reasonable option for severe post-prostate cancer treatment stricture when patients are unwilling or unable to undergo open reconstructive surgery. Incontinence should be expected. The need for additional procedures is common and in some men may be required periodically for the lifetime of the stent. PMID:21074796

Impact of Preoperative Patient Characteristics on Posturethroplasty Recurrence: The Significance of Stricture Length and Prior Treatments

PubMed Central

Bello, Jibril Oyekunle

2016-01-01

Introduction: Urethral strictures are common in urologic practice of Sub-Saharan Africa including Nigeria. We determine the rate of stricture recurrence following urethroplasty for anterior urethral strictures and evaluate preoperative variables that predict of stricture recurrence in our practice. Subjects and Methods: Thirty-six men who had urethroplasty for proven anterior urethral stricture disease between February 2012 and January 2015 were retrospectively analyzed. Preoperative factors including age, socioeconomic factors, comorbidities, etiology of strictures, stricture location, stricture length, periurethral spongiofibrosis, and prior stricture treatments were assessed for independent predictors of stricture recurrence. Results: The median age was 49.5 years (range 21-90), median stricture length was 4 cm (range 1-18 cm) and the overall recurrence rate was 27.8%. Postinfectious strictures, pan urethral strictures or multiple strictures involving the penile and bulbar urethra were more common. Most patients had penile circular fasciocutaneous flap urethroplasty. Following univariate analysis of potential preoperative predictors of stricture recurrence, stricture length, and prior treatments with dilations or urethrotomies were found to be significantly associated with stricture recurrence. On multivariate analysis, they both remained statistically significant. Patients who had prior treatments had greater odds of having a recurrent stricture (odds ratio 18, 95% confidence interval [CI] 1.4–224.3). Stricture length was dichotomized based on receiver operating characteristic (ROC) analysis, and strictures of length ≥5 cm had significantly greater recurrence (area under ROC curve of 0.825, 95% CI 0.690–0.960, P = 0.032). Conclusion: Patients who had prior dilatations or urethrotomies and those with long strictures particularly strictures ≥5 cm have significantly greater odds of developing a recurrence following urethroplasty in Nigerian urology practice. PMID:27843271

Redo buccal mucosa graft urethroplasty: success rate, oral morbidity and functional outcomes.

PubMed

Rosenbaum, Clemens M; Schmid, Marianne; Ludwig, Tim A; Kluth, Luis A; Dahlem, Roland; Fisch, Margit; Ahyai, Sascha

2016-11-01

To determine the success rate, oral morbidity and functional outcomes of redo buccal mucosa graft urethroplasty (BMGU) for treatment of stricture recurrence after previous BMGU. We included 50 patients who underwent redo BMGU between February 2009 and September 2014. Patients' charts and non-validated questionnaires were reviewed. The primary endpoint was success rate, defined as stricture-free survival. Stricture recurrence was defined as any postoperative claims of catheterization, dilatation, urethrotomy or repeat urethroplasty, or a maximum urinary flow rate <15 mL/s, and a stricture was consecutively verified in a combined cysto-urethrogram or cystoscopy at annual follow-up visit. The secondary endpoint was oral morbidity. Additional endpoints were erectile function, urinary continence and patients' satisfaction. Redo BMGU was performed for bulbar (71.4%) or penile (28.6%) recurrent strictures. The mean (median; range) follow-up was 25.6 (15.5; 3-70) months. Stricture recurrence occurred in 18.0% of patients within a mean (median; range) of 13.8 (9.0; 3-36) months. Stricture-free survival at 12, 24 and 36 months was 91.2, 86.2 and 80.8%, respectively. The majority of the patients (97.0%) reported no or only mildly changed salivation or problems in opening of the mouth. Severe or very severe oral numbness occurred in 13.5% of patients. Oral problems in daily life were a moderate or severe burden to 13.6 and 2.7% of the patients, respectively, while 75.0% of the patients reported improved quality of life compared with preoperative status. The success rate and oral morbidity of redo BMGU are almost the same as outcomes of primary BMGU. Oral numbness was the most frequently reported oral disorder. © 2016 The Authors BJU International © 2016 BJU International Published by John Wiley & Sons Ltd.

Looking beyond oral mucosa: Initial results of everted saphenous vein graft urethroplasty (eSVGU) in long anterior urethral strictures.

PubMed

Akhtar, Arif; Khattar, Nikhil; Goel, Hemant; Rao, Swatantra; Tanwar, Raman; Sood, Rajeev

2017-09-01

To prospectively evaluate the feasibility and initial results of an everted saphenous vein graft (eSVG) as a dorsolateral onlay, in patients with long anterior urethral strictures and/or chronic tobacco users. In all, 20 patients with long anterior urethral strictures (>7 cm) and/or chronic tobacco exposed oral mucosa were included in the study. The harvested SVG was hydro-distended, detubularised, and everted. Substitution urethroplasty using an eSVG was performed using a dorsolateral onlay technique. Symptoms were assessed using the International Prostate Symptom Score (IPSS) and uroflowmetry at 1, 3 and 6 months; and voiding and retrograde urethrograms, and urethroscopy were done at 3 months. Failure was defined as failure to void, need for interventions in form of direct-vision internal urethrotomy or endodilatation. Three patients were excluded because they underwent a staged urethroplasty. In all, 17 patients underwent eSVG substitution urethroplasty. The mean (SD, range) follow-up of our patients was 17.64 (5.23, 10-26) months. The mean (SD, range) length of the strictured segment was 14 (2.5, 10-18) cm and the length of the harvested SVG was 16.3 (2.7, 12-20) cm. The mean (SD) IPSS at 1, 3 and 6 months after catheter removal was 10 (2.8), 10 (3.4) and 10 (1.4) and the quality-of-life score was 1.76 (0.5), 2.05 (1.0) and 2.05 (1.0), respectively. Postoperatively, endodilatation was required in two patients. Complete failure occurred in one patient. An eSVG, as a dorsolateral onlay graft, is a promising and prudent option for long anterior urethral strictures, especially in patients with poor oral hygiene and chronic tobacco use.

Efficacy and safety of local steroids for urethra strictures: a systematic review and meta-analysis.

PubMed

Zhang, Kaile; Qi, Er; Zhang, Yumeng; Sa, Yinglong; Fu, Qiang

2014-08-01

Local steroids have been used as an adjuvant therapy to patients undergoing internal urethrotomy (IU) in treating urethral strictures. Whether this technique is effective and safe is still controversial. The aim of this study is to determine the efficacy and safety of local steroids as applied with the IU procedure. A systematic review of the literature was performed by searching Medline, Embase, Cochrane Library Databases, and the Web of Science. We included only prospective randomized, controlled trials that compared the efficacy and safety between IU procedures with applied local steroids and those without. Eight studies were found eligible for further analysis. In total, 203 patients undergoing IU were treated with steroid injection or catheter lubrication. Time to recurrence is statistically significant (mean: 10.14 and 5.07 months, P<0.00001).The number of patients with recurrent stricture formation significantly decreased at different follow-up time points (P=0.05).No statistically significant differences were found between the recurrence rates, adverse effects, and success rates of second IUs in patients with applied local steroids and those without. The use of local steroids with IU seems to prolong time to stricture recurrence but does not seem to affect the high stricture recurrence rate following IU. When local steroids are applied with complementary intention, the disease control outcomes are encouraging. Further robust comparative effectiveness studies are now required.

Outcomes of reintervention after failed urethroplasty.

PubMed

Ekerhult, Teresa Olsen; Lindqvist, Klas; Peeker, Ralph; Grenabo, Lars

2017-02-01

Urethroplasty is a procedure that has a high success rate. However, there exists a small subgroup of patients who require multiple procedures to achieve an acceptable result. This study analyses the outcomes of a series of patients with failed urethroplasty. This is a retrospective review of 82 failures out of 407 patients who underwent urethroplasty due to urethral stricture during the period 1999-2013. Failure was defined as the need for an additional surgical procedure. Of the failures, 26 patients had penile strictures and 56 had bulbar strictures. Meatal strictures were not included. The redo procedures included one or multiple direct vision internal urethrotomies, dilatations or new urethroplasties, all with a long follow-up time. The patients underwent one to seven redo surgeries (mean 2.4 procedures per patient). In the present series of patients, endourological procedures cured 34% (28/82) of the patients. Ten patients underwent multiple redo urethroplasties until a satisfactory outcome was achieved; the penile strictures were the most difficult to cure. In patients with bulbar strictures, excision with anastomosis and substitution urethroplasty were equally successful. Nevertheless, 18 patients were defined as treatment failures. Of these patients, nine ended up with clean intermittent self-dilatation as a final solution, five had perineal urethrostomy and four are awaiting a new reintervention. Complicated cases need centralized professional care. Despite the possibility of needing multiple reinterventions, the majority of patients undergoing urethroplasty have a good chance of successful treatment.

Multivariate analysis of risk factors for long-term urethroplasty outcome.

PubMed

Breyer, Benjamin N; McAninch, Jack W; Whitson, Jared M; Eisenberg, Michael L; Mehdizadeh, Jennifer F; Myers, Jeremy B; Voelzke, Bryan B

2010-02-01

We studied the patient risk factors that promote urethroplasty failure. Records of patients who underwent urethroplasty at the University of California, San Francisco Medical Center between 1995 and 2004 were reviewed. Cox proportional hazards regression analysis was used to identify multivariate predictors of urethroplasty outcome. Between 1995 and 2004, 443 patients of 495 who underwent urethroplasty had complete comorbidity data and were included in analysis. Median patient age was 41 years (range 18 to 90). Median followup was 5.8 years (range 1 month to 10 years). Stricture recurred in 93 patients (21%). Primary estimated stricture-free survival at 1, 3 and 5 years was 88%, 82% and 79%. After multivariate analysis smoking (HR 1.8, 95% CI 1.0-3.1, p = 0.05), prior direct vision internal urethrotomy (HR 1.7, 95% CI 1.0-3.0, p = 0.04) and prior urethroplasty (HR 1.8, 95% CI 1.1-3.1, p = 0.03) were predictive of treatment failure. On multivariate analysis diabetes mellitus showed a trend toward prediction of urethroplasty failure (HR 2.0, 95% CI 0.8-4.9, p = 0.14). Length of urethral stricture (greater than 4 cm), prior urethroplasty and failed endoscopic therapy are predictive of failure after urethroplasty. Smoking and diabetes mellitus also may predict failure potentially secondary to microvascular damage. Copyright 2010 American Urological Association. Published by Elsevier Inc. All rights reserved.

What is the most cost-effective treatment for 1 to 2-cm bulbar urethral strictures: societal approach using decision analysis.

PubMed

Wright, Jonathan L; Wessells, Hunter; Nathens, Avery B; Hollingworth, Will

2006-05-01

Direct vision internal urethrotomy (DVIU) and urethroplasty are the primary methods of managing urethral stricture disease. Using decision analysis, we determine the cost-effectiveness of different management strategies for short, bulbar urethral strictures 1 to 2 cm in length. A decision tree was constructed, with the number of planned possible DVIUs before attempting urethroplasty defined for each primary branch point. Success rates were obtained from published reports. Costs were estimated from a societal perspective and included the costs of the procedures and office visits and lost wages from convalescence. Sensitivity analyses were conducted, varying the success rates of the procedures and cost estimates. The most cost-effective approach was one DVIU before urethroplasty. The incremental cost of performing a second DVIU before attempting urethroplasty was $141,962 for each additional successfully voiding patient. In the sensitivity analysis, urethroplasty as the primary therapy was cost-effective only when the expected success rate of the first DVIU was less than 35%. The most cost-effective strategy for the management of short, bulbar urethral strictures is to reserve urethroplasty for patients in whom a single endoscopic attempt fails. For longer strictures for which the success rate of DVIU is expected to be less than 35%, urethroplasty as primary therapy is cost-effective. Future prospective, multicenter studies of DVIU and urethroplasty outcomes would help enhance the accuracy of our model.

Use of a laparoscopic specimen retrieval pouch to facilitate removal of intact or fragmented cystic calculi from standing sedated horses: 8 cases (2012-2015).

PubMed

Katzman, Scott A; Vaughan, Betsy; Nieto, Jorge E; Galuppo, Larry D

2016-08-01

OBJECTIVE To evaluate the use of a laparoscopic specimen retrieval pouch for removal of intact or fragmented cystic calculi from standing horses. DESIGN Retrospective case series. ANIMALS 8 horses (5 geldings and 3 mares) with cystic calculi. PROCEDURES Physical examination and cystoscopic, ultrasonographic, and hematologic evaluations of urinary tract function were performed for each horse. A diagnosis of cystic calculus was made on the basis of results of cystoscopy and ultrasonography. Concurrent urolithiasis or other urinary tract abnormalities identified during preoperative evaluation were recorded. Horses were sedated and placed in standing stocks, and the perineum was aseptically prepared. Direct access to the urinary bladder was gained in geldings via perineal urethrotomy or in mares by a transurethral approach. Calculi were visualized endoscopically, manipulated into the retrieval pouch, and removed intact or fragmented (for larger calculi). RESULTS For 4 geldings and 1 mare, fragmentation was necessary to facilitate calculus removal. Mean duration of surgery was 125 minutes, and trauma to the urinary bladder and urethra was limited to areas of hyperemia and submucosal petechiation. No postoperative complications were encountered for any horse. When lithotripsy was required, the retrieval pouch provided an effective means of stabilizing calculi and containing the fragments for removal. CONCLUSIONS AND CLINICAL RELEVANCE Use of the laparoscopic specimen retrieval pouch was an effective, minimally traumatic method for retrieving cystic calculi from standing horses. The pouch protected the urinary bladder and urethra from trauma during calculus removal and allowed for stabilization, containment, and fragmentation of calculi when necessary.

Perceptions of Visual Literacy. Selected Readings from the Annual Conference of the International Visual Literacy Association (21st, Scottsdale, Arizona, October 1989).

ERIC Educational Resources Information Center

Braden, Roberts A., Ed.; And Others

These proceedings contain 37 papers from 51 authors noted for their expertise in the field of visual literacy. The collection is divided into three sections: (1) "Examining Visual Literacy" (including, in addition to a 7-year International Visual Literacy Association bibliography covering the period from 1983-1989, papers on the perception of…

Acellular bi-layer silk fibroin scaffolds support tissue regeneration in a rabbit model of onlay urethroplasty.

PubMed

Chung, Yeun Goo; Tu, Duong; Franck, Debra; Gil, Eun Seok; Algarrahi, Khalid; Adam, Rosalyn M; Kaplan, David L; Estrada, Carlos R; Mauney, Joshua R

2014-01-01

Acellular scaffolds derived from Bombyx mori silk fibroin were investigated for their ability to support functional tissue regeneration in a rabbit model of urethra repair. A bi-layer silk fibroin matrix was fabricated by a solvent-casting/salt leaching process in combination with silk fibroin film casting to generate porous foams buttressed by homogeneous silk fibroin films. Ventral onlay urethroplasty was performed with silk fibroin grafts (Group 1, N = 4) (Width × Length, 1 × 2 cm(2)) in adult male rabbits for 3 m of implantation. Parallel control groups consisted of animals receiving small intestinal submucosa (SIS) implants (Group 2, N = 4) or urethrotomy alone (Group 3, N = 3). Animals in all groups exhibited 100% survival prior to scheduled euthanasia and achieved voluntary voiding following 7 d of initial catheterization. Retrograde urethrography of each implant group at 3 m post-op revealed wide urethral calibers and preservation of organ continuity similar to pre-operative and urethrotomy controls with no evidence of contrast extravasation, strictures, fistulas, or stone formation. Histological (hematoxylin and eosin and Masson's trichrome), immunohistochemical, and histomorphometric analyses demonstrated that both silk fibroin and SIS scaffolds promoted similar extents of smooth muscle and epithelial tissue regeneration throughout the original defect sites with prominent contractile protein (α-smooth muscle actin and SM22α) and cytokeratin expression, respectively. De novo innervation and vascularization were also evident in all regenerated tissues indicated by synaptophysin-positive neuronal cells and vessels lined with CD31 expressing endothelial cells. Following 3 m post-op, minimal acute inflammatory reactions were elicited by silk fibroin scaffolds characterized by the presence of eosinophil granulocytes while SIS matrices promoted chronic inflammatory responses indicated by mobilization of mononuclear cell infiltrates. The results of this study demonstrate that bi-layer silk fibroin scaffolds represent promising biomaterials for onlay urethroplasty, capable of promoting similar degrees of tissue regeneration in comparison to conventional SIS scaffolds, but with reduced immunogenicity.

Acellular Bi-Layer Silk Fibroin Scaffolds Support Tissue Regeneration in a Rabbit Model of Onlay Urethroplasty

PubMed Central

Franck, Debra; Gil, Eun Seok; Algarrahi, Khalid; Adam, Rosalyn M.; Kaplan, David L.; Estrada Jr., Carlos R.; Mauney, Joshua R.

2014-01-01

Acellular scaffolds derived from Bombyx mori silk fibroin were investigated for their ability to support functional tissue regeneration in a rabbit model of urethra repair. A bi-layer silk fibroin matrix was fabricated by a solvent-casting/salt leaching process in combination with silk fibroin film casting to generate porous foams buttressed by homogeneous silk fibroin films. Ventral onlay urethroplasty was performed with silk fibroin grafts (Group 1, N = 4) (Width×Length, 1×2 cm2) in adult male rabbits for 3 m of implantation. Parallel control groups consisted of animals receiving small intestinal submucosa (SIS) implants (Group 2, N = 4) or urethrotomy alone (Group 3, N = 3). Animals in all groups exhibited 100% survival prior to scheduled euthanasia and achieved voluntary voiding following 7 d of initial catheterization. Retrograde urethrography of each implant group at 3 m post-op revealed wide urethral calibers and preservation of organ continuity similar to pre-operative and urethrotomy controls with no evidence of contrast extravasation, strictures, fistulas, or stone formation. Histological (hematoxylin and eosin and Masson's trichrome), immunohistochemical, and histomorphometric analyses demonstrated that both silk fibroin and SIS scaffolds promoted similar extents of smooth muscle and epithelial tissue regeneration throughout the original defect sites with prominent contractile protein (α-smooth muscle actin and SM22α) and cytokeratin expression, respectively. De novo innervation and vascularization were also evident in all regenerated tissues indicated by synaptophysin-positive neuronal cells and vessels lined with CD31 expressing endothelial cells. Following 3 m post-op, minimal acute inflammatory reactions were elicited by silk fibroin scaffolds characterized by the presence of eosinophil granulocytes while SIS matrices promoted chronic inflammatory responses indicated by mobilization of mononuclear cell infiltrates. The results of this study demonstrate that bi-layer silk fibroin scaffolds represent promising biomaterials for onlay urethroplasty, capable of promoting similar degrees of tissue regeneration in comparison to conventional SIS scaffolds, but with reduced immunogenicity. PMID:24632740

Survey of Visual Ground Aids at O'Hare International Airport.

DOT National Transportation Integrated Search

1975-01-01

During the period June - July 1974 a survey of Visual Ground Aids was conducted at O'Hare International Airport in Chicago, Illinois. The purpose of this survey was to identify equipment currently installed to aid in providing visual guidance to pilo...

VisionQuest: Journeys toward Visual Literacy. Selected Readings from the Annual Conference of the International Visual Literacy Association (28th, Cheyenne, Wyoming, October, 1996).

ERIC Educational Resources Information Center

Griffin, Robert E., Ed.; And Others

This document contains 59 selected papers from the 1996 International Visual Literacy Association (IVLA) conference. Topics include: learning to think visually; information design via the Internet; a program for inner-city at-risk children; dubbing versus subtitling television programs; connecting advertisements and classroom reading through…

[Personal experience with treatment of posttraumatic urethral distraction defects].

PubMed

Fiala, R; Zátura, F; Vrtal, R

2001-01-01

Authors present their experience in the treatment of posttraumatic distraction urethral defect resulting from traumatic rupture of posterior urethra. The group comprised 19 patients with posttraumatic urethral distraction defect (average age 41 year, range 27-65 years). In 16 of them (84%) resection urehtroplasty was performed and in three (16%) endoscopic internal urethrotomy was applied. The patients were evaluated of 19 to 48 months after surgery. Urethroplasty was performed at least three months after the trauma, always under general anesthaesia in lithotomic position, using perinal approach. Dissection of bulbar urethra was followed by dissection and resection of fibrous posttraumatic distraction defect (the original membranous urethra). Prostatic apex and proximal end of lumbar urethra were spatulated and bulboprostatic anastomosis was performed restoring urethral continuity. A catheter was left in urethra for three weeks. In 12 patients it was necessary to separe corpora cavernosa addition and 5 patients required a wedge resection of the lower arch of public bones to allow urethral bridge the defect. Endoscopic internal urehtrotomy was also performed minimally three months after trauma, always on position 12 of the clock face opposite to symphysis with a discision of the whole stenotic part. Subsequently, catheter was inserted in urethra and left in place for four days. Resection urethroplasty as primary surgery was successful in 15 (94%) patients and only 1 patients (6%) required another reconstruction surgery. Endoscopic management was not successful in any patients (100%). Two of them (66%) had to undergo repeatedly a reconstruction surgery, the third one (33%) is regularly dilated. All patients after urethroplasty are under regular circumstances continent, only in two of them (13%) there occurs of urine in case of an extreme increase of abdominal pressure. Erectile function already impaired by the trauma did not worsen by the surgery in 4 patients (25%), in 2 patients (13%) with preoperatively normal erections there developed erectile dysfunction after urethroplasty of which in 1 patient a permanent disorder. The quality of life was in general evaluated by patients as excellent. Epicystotomy is a simple procedure ensuring urinary diversion in patients with posterior urethral rupture. However, such management of urethral rupture almost always results in the development posttraumatic distraction defect. Incontinence occurs in our group only in 2 (12%) patients, mainly in non-standard situations (gym, urgency). Night incontinence does not occur in our patients at all. Continence is in our patients ensured by lissosfincter which is fully sufficient. Erectile dysfunction may result from a trauma or a treatment. In our group all patients have a preserved erection prior to trauma and trauma was evident cause of the loss of erection only in 2 (12%) patients who were primarily treated by epicystotomy. In another 2 patients (12%) who were primarily treated after trauma for coincidental urinary bladder rupture it is impossible to state what caused the erectile dysfunction whether a fracture or surgery. In the acute phase during the revision of the rupture of posterior urethra the peroperative risk of the impairment of neurovascular bundles responsible for erection is much higher than in planned surgery. Satisfaction of patients with the treatment is reflected in the evaluation of the postoperative results and the quality of life in general. None of our patients managed by delayed internal urethrotomy was cured. One is regularly dilated, another two underwent urethroplasty. The technique of resection of urethral distraction defects with bulboprostatic anastomosis is a suitable way of the treatment of the preceding rupture of posterior urethra without impairement of continence or erection. A prerequisite of good results is a simple urine diversion by epicystostomy during the primary management of the posterior urethral rupture. Delayed endoscopic therapy of the distraction defect will not probably cure the patients but will result in regular dilatations. It may be an alternative treatment in polymorbid or biologically older patients.

Visible and Viable: The Role of Images in Instruction and Communication. Readings from the Annual Conference of the International Visual Literacy Association (18th, Commerce, Texas, 1987).

ERIC Educational Resources Information Center

Braden, Roberts A., Ed.; And Others

Presentations at the International Visual Literacy Association conference are grouped under five topics, a prologue, and an epilogue: (1) Prologue--"Writing About Visual Literacy" (Roberts A. Braden); (2) Visible Language--four papers concerning picture books, the Macintosh and Laserwriter, the design of library signs, and visual literacy and…

Visual Literacy in the Digital Age: Selected Readings from the Annual Conference of the International Visual Literacy Association (25th, Rochester, New York, October 13-17, 1993).

ERIC Educational Resources Information Center

Beauchamp, Darrel G.; And Others

This document contains selected papers from the 25th annual conference of the International Visual Literacy Association (IVLA). Topics addressed in the papers include the following: visual literacy; graphic information in research and education; evaluation criteria for instructional media; understanding symbols in business presentations;…

Viewing the World: Visual Inquiry in International Settings

ERIC Educational Resources Information Center

Munn, Jean Correll

2012-01-01

This teaching note describes a course, Viewing the World: Visual Inquiry in International Settings, which the author taught in the Czech Republic in 2009. Five students successfully completed the course, which consisted of designing a project, collecting and analyzing visual data, presenting findings, and writing a final report of a qualitative…

The giant calculus within the prostatic urethra.

PubMed

Demir, Omer; Kefi, Aykut; Cahangirov, Asif; Cihan, Ahmet; Obuz, Funda; Esen, Adil Ahmet; Celebi, Ilhan

2011-08-01

The giant calculus within the prostatic urethra is a rare clinical entity in the young population. Most of the calculi within the urethra migrate from the urinary bladder and obliterate the urethra. These stones are often composed of calcium phosphate or calcium oxalate. The decision of treatment strategy is affected by the size, shape and position of the calculus and by the status of the urethra. If the stone is large and immovable, it may be extracted via the perineal or the suprapubic approach. In most cases, the giant calculi were extracted via the transvesical approach and external urethrotomy. Our case is the biggest prostatic calculus, known in the literature so far, which was treated endoscopically by the combination of laser and the pneumatic lithotriptor.

Looking for ideas: Eye behavior during goal-directed internally focused cognition☆

PubMed Central

Walcher, Sonja; Körner, Christof; Benedek, Mathias

2017-01-01

Humans have a highly developed visual system, yet we spend a high proportion of our time awake ignoring the visual world and attending to our own thoughts. The present study examined eye movement characteristics of goal-directed internally focused cognition. Deliberate internally focused cognition was induced by an idea generation task. A letter-by-letter reading task served as external task. Idea generation (vs. reading) was associated with more and longer blinks and fewer microsaccades indicating an attenuation of visual input. Idea generation was further associated with more and shorter fixations, more saccades and saccades with higher amplitudes as well as heightened stimulus-independent variation of eye vergence. The latter results suggest a coupling of eye behavior to internally generated information and associated cognitive processes, i.e. searching for ideas. Our results support eye behavior patterns as indicators of goal-directed internally focused cognition through mechanisms of attenuation of visual input and coupling of eye behavior to internally generated information. PMID:28689088

Expectations for Visual Function: An Initial Evaluation of a New Clinical Instrument.

ERIC Educational Resources Information Center

Corn, Anne L.; Webne, Steve L.

2001-01-01

A study explored the internal consistency of items in a visual screening instrument developed by Project PAVE: Expectations for Visual Functioning (EVF). The test includes 20 items that evaluate a child's functional use of vision. A pilot test involving 129 teachers indicates the EFV is internally consistent. (Contains three references.) (CR)

Barriers to accessing urethroplasty

PubMed Central

Consolo, Michael J.; Syed, Kirin K.; Robison, Christopher; McFadden, Jacob; Shalowitz, David I.; Brown, Gordon A.; Sussman, David O.; Figler, Bradley D.

2016-01-01

Urethroplasty is an effective treatment for men with anterior urethral strictures, but is utilized less frequently than ineffective treatments such as internal urethrotomy. We sought to identify provider-level barriers to urethroplasty. An anonymous online survey was emailed to all Mid-Atlantic American Urological Association members. Six scenarios in which urethroplasty was the most appropriate treatment were presented. Primary outcome was recommendation for urethroplasty in ≥ three clinical scenarios. Other factors measured include practice zip code, urethroplasty training, and proximity to a urethroplasty surgeon. Multivariate logistic regression identified factors associated with increased likelihood of urethroplasty recommendation. Of 670 members emailed, 109 (16%) completed the survey. Final analysis included 88 respondents. Mean years in practice was 17.2. Most respondents received formal training in urethroplasty: 43 (49%) in residency, 5 (6%) in fellowship, and 10 (11%) in both; 48 respondents (55%) had a urethroplasty surgeon in their practice, whereas 18 (20%) had a urethroplasty surgeon within 45 minutes of his or her primary practice location. The only covariate that was associated with an increased likelihood of recommending urethroplasty in ≥ three scenarios was formal urethroplasty training. Most members (68%) reported no barriers to referring patients for urethroplasty; the most common barriers cited were long distance to urethroplasty surgeon (n 5 13, 15%) and concern about complications (n 5 8, 9%). Urethroplasty continues to be underutilized in men with anterior urethral strictures, potentially due to lack of knowledge dissemination and access to a urethroplasty surgeon. Appropriate urethroplasty utilization may increase with greater exposure to urethroplasty in training. PMID:28127260

Current management of urethral stricture disease

PubMed Central

Smith, Thomas G.

2016-01-01

Introduction: Broadly defined, urethral strictures are narrowing of the urethral lumen that is surrounded by corpus spongiosum, i.e., urethral meatus through the bulbar urethra. Urethral stenosis is narrowing of the posterior urethra, i.e., membranous urethra through bladder neck/prostate junction, which is not enveloped by corpus spongiosum. The disease has significant quality of life ramifications because many times younger patients are affected by this compared to many other urological diseases. Methods: A review of the scientific literature concerning urethral stricture, stenosis, treatment, and outcomes was performed using Medline and PubMed (U.S. National Library of Medicine and the National Institutes of Health). Abstracts from scientific meetings were included in this review. Results: There is level 3 evidence regarding the etiology and epidemiology of urethral strictures, stenoses, and pelvic fracture urethral injuries. Outcomes data from literature regarding intervention for urethral stricture are largely limited to level 3 evidence and expert opinion. There is a single level 1 study comparing urethral dilation and direct vision internal urethrotomy. Urethroplasty outcomes data are limited to level 3 case series. Conclusions: Progress is being made toward consistent terminology, and nomenclature which will, in turn, help to standardize treatment within the field of urology. Treatment for urethral stricture and stenosis remains inconsistent between reconstructive and nonreconstructive urologists due to varying treatment algorithms and approaches to disease management. Tissue engineering appears to be future for reconstructive urethral surgery with reports demonstrating feasibility in the use of different tissue substitutes and grafts. PMID:26941491

Barriers to accessing urethroplasty.

PubMed

Consolo, Michael J; Syed, Kirin K; Robison, Christopher; McFadden, Jacob; Shalowitz, David I; Brown, Gordon A; Sussman, David O; Figler, Bradley D

2016-01-01

Urethroplasty is an effective treatment for men with anterior urethral strictures, but is utilized less frequently than ineffective treatments such as internal urethrotomy. We sought to identify provider-level barriers to urethroplasty. An anonymous online survey was emailed to all Mid-Atlantic American Urological Association members. Six scenarios in which urethroplasty was the most appropriate treatment were presented. Primary outcome was recommendation for urethroplasty in ≥ three clinical scenarios. Other factors measured include practice zip code, urethroplasty training, and proximity to a urethroplasty surgeon. Multivariate logistic regression identified factors associated with increased likelihood of urethroplasty recommendation. Of 670 members emailed, 109 (16%) completed the survey. Final analysis included 88 respondents. Mean years in practice was 17.2. Most respondents received formal training in urethroplasty: 43 (49%) in residency, 5 (6%) in fellowship, and 10 (11%) in both; 48 respondents (55%) had a urethroplasty surgeon in their practice, whereas 18 (20%) had a urethroplasty surgeon within 45 minutes of his or her primary practice location. The only covariate that was associated with an increased likelihood of recommending urethroplasty in ≥ three scenarios was formal urethroplasty training. Most members (68%) reported no barriers to referring patients for urethroplasty; the most common barriers cited were long distance to urethroplasty surgeon (n 5 13, 15%) and concern about complications (n 5 8, 9%). Urethroplasty continues to be underutilized in men with anterior urethral strictures, potentially due to lack of knowledge dissemination and access to a urethroplasty surgeon. Appropriate urethroplasty utilization may increase with greater exposure to urethroplasty in training.

Factors that influence the outcome of open urethroplasty for pelvis fracture urethral defect (PFUD): an observational study from a single high-volume tertiary care center.

PubMed

Fu, Qiang; Zhang, Yu-meng; Barbagli, Guido; Zhang, Jiong; Xie, Hong; Sa, Ying-long; Jin, San-bao; Xu, Yue-min

2015-12-01

To report the clinical features of pelvic fracture urethral injury (PFUI) and assess the real effect of factors that are believed to have adverse effects on delayed urethroplasty. An observational descriptive study in a single urological center examined 376 male patients diagnosed with PFUI who underwent open urethroplasty from 2009 to 2013. Analyzed factors included patient age at the time of injury, etiology of PFUI, type of emergency treatment, concomitant injuries, length and position of stricture, type of urethroplasty and the outcome of surgery. Univariate and multivariate logistic regression analyses were applied, together with analytical statistic methods such as t test and Chi-square test. The overall success rate of delayed urethroplasty was 80.6 %. Early realignment was associated with reduced stricture length and had beneficial effect on delayed surgery. Concomitant rectum rupture, strictures longer than 1.6 cm and strictures closer than 3 cm to the bladder neck were indicators of poor outcome. Age, type of injury, urethral fistula and bladder rupture were not significant predicators of surgery outcome. Failed direct vision internal urethrotomy and urethroplasty had no significant influence on salvage operation. The outcome of posterior urethroplasty is affected by multiple factors. Early realignment has beneficial effect; while the length and position of stricture and its distance to bladder neck plays the key role, rectum rupture at the time of injury is also an indicator of poor outcome. The effect of other factors seems insignificant.

Primary urethral reconstruction: the cost minimized approach to the bulbous urethral stricture.

PubMed

Rourke, Keith F; Jordan, Gerald H

2005-04-01

Treatment for urethral stricture disease often requires a choice between readily available direct vision internal urethrotomy (DVIU) and highly efficacious but more technically complex open urethral reconstruction. Using the short segment bulbous urethral stricture as a model, we determined which strategy is less costly. The costs of DVIU and open urethral reconstruction with stricture excision and primary anastomosis for a 2 cm bulbous urethral stricture were compared using a cost minimization decision analysis model. Clinical probability estimates for the DVIU treatment arm were the risk of bleeding, urinary tract infection and the risk of stricture recurrence. Estimates for the primary urethral reconstruction strategy were the risk of wound complications, complications of exaggerated lithotomy and the risk of treatment failure. Direct third party payer costs were determined in 2002 United States dollars. The model predicted that treatment with DVIU was more costly (17,747 dollars per patient) than immediate open urethral reconstruction (16,444 dollars per patient). This yielded an incremental cost savings of $1,304 per patient, favoring urethral reconstruction. Sensitivity analysis revealed that primary treatment with urethroplasty was economically advantageous within the range of clinically relevant events. Treatment with DVIU became more favorable when the long-term risk of stricture recurrence after DVIU was less than 60%. Treatment for short segment bulbous urethral strictures with primary reconstruction is less costly than treatment with DVIU. From a fiscal standpoint urethral reconstruction should be considered over DVIU in the majority of clinical circumstances.

Early endoscopic realignment of post-traumatic posterior urethral disruption.

PubMed

Moudouni, S M; Patard, J J; Manunta, A; Guiraud, P; Lobel, B; Guillé, F

2001-04-01

The management of complete or partial urethral disruption is controversial, and much debate continues regarding immediate versus delayed definitive therapy. We further analyze our experience and long-term results using early endoscopic realignment. Between April 1987 and January 1999, 29 men with posterior urethral disruption (23 complete and 6 partial) underwent primary urethral realignment 0 to 8 days after injury. Pelvic fractures were present in 23 patients. In all patients, the actual operating time for realignment was 75 minutes or less. All patients were evaluated postoperatively for incontinence, impotence, and strictures. After a mean follow-up of 68 months (range 18 to 155), all patients were continent. Four patients (13.7%) required conversion to an open perineal urethroplasty. At the last follow-up visit, 25 (86%) of the 29 patients were potent and 4 achieved adequate erections for intercourse using intracorporeal injections (prostaglandin E(1)). Twelve patients (41%) developed short secondary strictures and were successfully treated with internal urethrotomy. The mean follow-up of these 12 patients was 83 months (range 34 to 120). Urinary flow rate measurement at the last follow-up visit revealed satisfactory voiding parameters in all patients. Primary endoscopic realignment offers an effective method for treating traumatic urethral injuries. Our long-term follow-up provides additional support for the use of this technique by demonstrating that urethral continuity can be established without an increased incidence of impotence, stricture formation, or incontinence. In case of failure, endoscopic realignment does not compromise the result of secondary urethroplasty.

Transvesicular percutaneous cystolithotomy for the retrieval of cystic and urethral calculi in dogs and cats: 27 cases (2006-2008).

PubMed

Runge, Jeffrey J; Berent, Allyson C; Mayhew, Philipp D; Weisse, Chick

2011-08-01

To describe the use of transvesicular percutaneous cystolithotomy for the retrieval of cystic and urethral calculi and to report the outcome in dogs and cats. Retrospective case series. 23 dogs and 4 cats. Medical records were reviewed for signalment, procedure time, stone number, stone location, pre- and postoperative radiographs, procedure-associated complications, and short-term outcome. A ventral midline approach was made into the abdomen over the urinary bladder apex. A screw cannula was inserted at the bladder apex for normograde rigid and flexible cystourethroscopy. All uroliths were removed via a stone basket device and retrograde flushing and suction. Long-term follow-up (1 year after surgery) information was obtained by telephone or e-mail contact with owners. 27 animals with cystic and urethral calculi were included. Median patient weight was 8.3 kg (18.3 lb; range, 1.8 to 42.6 kg [4.0 to 93.7 lb]). Urolith number ranged from 1 to > 35 (median, 7). Urolith size ranged from < 1 to 30 mm (median, 4.5 mm). Fifteen of the 27 animals had a previous cystotomy (range, 1 to 5 procedures). Median procedure time was 66 minutes (range, 50 to 80 minutes). All patients were discharged within 24 hours. No postoperative complications were reported at the time of suture removal. At the time of long-term follow-up, the 22 clients that could be contacted were satisfied with the procedure. Transvesicular percutaneous cystolithotomy may decrease the need for urethrotomy, serial transurethral endoscopic procedures, and abdominal insufflation associated with other minimally invasive interventions currently available. This procedure also provided excellent visualization for bladder and urethral luminal inspection.

Visual recovery in cortical blindness is limited by high internal noise

PubMed Central

Cavanaugh, Matthew R.; Zhang, Ruyuan; Melnick, Michael D.; Das, Anasuya; Roberts, Mariel; Tadin, Duje; Carrasco, Marisa; Huxlin, Krystel R.

2015-01-01

Damage to the primary visual cortex typically causes cortical blindness (CB) in the hemifield contralateral to the damaged hemisphere. Recent evidence indicates that visual training can partially reverse CB at trained locations. Whereas training induces near-complete recovery of coarse direction and orientation discriminations, deficits in fine motion processing remain. Here, we systematically disentangle components of the perceptual inefficiencies present in CB fields before and after coarse direction discrimination training. In seven human CB subjects, we measured threshold versus noise functions before and after coarse direction discrimination training in the blind field and at corresponding intact field locations. Threshold versus noise functions were analyzed within the framework of the linear amplifier model and the perceptual template model. Linear amplifier model analysis identified internal noise as a key factor differentiating motion processing across the tested areas, with visual training reducing internal noise in the blind field. Differences in internal noise also explained residual perceptual deficits at retrained locations. These findings were confirmed with perceptual template model analysis, which further revealed that the major residual deficits between retrained and intact field locations could be explained by differences in internal additive noise. There were no significant differences in multiplicative noise or the ability to process external noise. Together, these results highlight the critical role of altered internal noise processing in mediating training-induced visual recovery in CB fields, and may explain residual perceptual deficits relative to intact regions of the visual field. PMID:26389544

International Practice in Care Provision for Post-stroke Visual Impairment.

PubMed

Rowe, Fiona J

2017-09-01

This study sought to explore the practice of orthoptists internationally in care provision for poststroke visual impairment. Survey questions were developed and piloted with clinicians, academics, and users. Questions addressed types of visual problems, how these were identified, treated, and followed up, care pathways in use, links with other professions, and referral options. The survey was approved by the institutional ethical committee. The survey was accessed via a web link that was circulated through the International Orthoptic Association member professional organisations to orthoptists. Completed electronic surveys were obtained from 299 individuals. About one-third (35.5%) of orthoptists saw patients within 2 weeks of stroke onset and over half (55.5%) by 1 month post stroke. Stroke survivors were routinely assessed by 87%; over three-quarters in eye clinics. Screening tools were used by 11%. Validated tests were used for assessment of visual acuity (76.5%), visual field (68.2%), eye movement (80.9%), binocular vision (77.9%), and visual function (55.8%). Visual problems suspected by family or professionals were high (86.6%). Typical overall follow-up period of vision care was less than 3 months. Designated care pathways for stroke survivors with visual problems were used by 56.9% of orthoptists. Information on visual impairment was provided by 85.9% of orthoptists. In international orthoptic practice, there is general agreement on assessment and management of visual impairment in stroke populations. More than half of orthoptists reported seeing stroke survivors within 1 month of the stroke onset, typically in eye clinics. There was a high use of validated tests of visual acuity, visual fields, ocular motility, and binocular vision. Similarly there was high use of established treatment options including prisms, occlusion, compensatory strategies, and oculomotor training, appropriately targeted at specific types of visual conditions/symptoms. This information can be used to inform choice of core outcome orthoptic measures in stroke practice.

26 CFR 48.4082-3 - Diesel fuel and kerosene; visual inspection devices. [Reserved

Code of Federal Regulations, 2012 CFR

2012-04-01

... 26 Internal Revenue 16 2012-04-01 2012-04-01 false Diesel fuel and kerosene; visual inspection devices. [Reserved] 48.4082-3 Section 48.4082-3 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF... Vehicles, Tires, Tubes, Tread Rubber, and Taxable Fuel Taxable Fuel § 48.4082-3 Diesel fuel and kerosene...

26 CFR 48.4082-3 - Diesel fuel and kerosene; visual inspection devices. [Reserved

Code of Federal Regulations, 2011 CFR

2011-04-01

... 26 Internal Revenue 16 2011-04-01 2011-04-01 false Diesel fuel and kerosene; visual inspection devices. [Reserved] 48.4082-3 Section 48.4082-3 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF... Vehicles, Tires, Tubes, Tread Rubber, and Taxable Fuel Taxable Fuel § 48.4082-3 Diesel fuel and kerosene...

26 CFR 48.4082-3 - Diesel fuel and kerosene; visual inspection devices. [Reserved

Code of Federal Regulations, 2013 CFR

2013-04-01

... 26 Internal Revenue 16 2013-04-01 2013-04-01 false Diesel fuel and kerosene; visual inspection devices. [Reserved] 48.4082-3 Section 48.4082-3 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF... Vehicles, Tires, Tubes, Tread Rubber, and Taxable Fuel Taxable Fuel § 48.4082-3 Diesel fuel and kerosene...

26 CFR 48.4082-3 - Diesel fuel and kerosene; visual inspection devices. [Reserved

Code of Federal Regulations, 2010 CFR

2010-04-01

... 26 Internal Revenue 16 2010-04-01 2010-04-01 true Diesel fuel and kerosene; visual inspection devices. [Reserved] 48.4082-3 Section 48.4082-3 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF... Vehicles, Tires, Tubes, Tread Rubber, and Taxable Fuel Taxable Fuel § 48.4082-3 Diesel fuel and kerosene...

The visual system’s internal model of the world

PubMed Central

Lee, Tai Sing

2015-01-01

The Bayesian paradigm has provided a useful conceptual theory for understanding perceptual computation in the brain. While the detailed neural mechanisms of Bayesian inference are not fully understood, recent computational and neurophysiological works have illuminated the underlying computational principles and representational architecture. The fundamental insights are that the visual system is organized as a modular hierarchy to encode an internal model of the world, and that perception is realized by statistical inference based on such internal model. In this paper, I will discuss and analyze the varieties of representational schemes of these internal models and how they might be used to perform learning and inference. I will argue for a unified theoretical framework for relating the internal models to the observed neural phenomena and mechanisms in the visual cortex. PMID:26566294

Correlation of Visual Prostate Symptom Score with International Prostate Symptom Score and Uroflowmetry Parameters in Nepalese Male Patients with Lower Urinary Tract Symptoms.

PubMed

Bhomi, K K; Subedi, N; Panta, P P

2017-01-01

International prostate symptom score is a validated questionnaire used to evaluate the lower urinary tract symptoms in benign prostatic hyperplasia. Visual prostate symptom score is a new simplified symptom score with pictograms to evaluate the same. We evaluated the correlation of visual prostate symptom score with international prostate symptom score and uroflowmetry parameters in Nepalese male patients with lower urinary tract symptoms. Male patients aged ≥40 years attending the Urology clinic were enrolled in the study. They were given international prostate symptom score and visual prostate symptom score questionnaires to complete providing assistance whenever needed. Demographic data, examination findings and uroflowmetry parameters were noted. Correlation and regression analysis was used to identify correlation of the two scoring systems and uroflowmetry parameters. Among the 66 patients enrolled, only 10 (15.15%) patients were able to understand English language. There was a statistically significant correlation between total visual prostate symptom score and international prostate symptom score (r= 0.822; P<0.01). The correlations between individual scores of the two scoring systems related to force of urinary stream, frequency, nocturia and quality of life were also statistically significant. There was also a statistically significant correlation of both scores with maximum flow rate and average flow rate. There is a statistically significant correlation of visual prostate symptom score with international prostate symptom score and uroflowmetry parameters. IPSS can be replaced with simple VPSS in evaluation of lower urinary tract symptoms in elderly male patients.

Eyes on the Future: Converging Images, Ideas, and Instruction. Selected Readings from the Annual Conference of the International Visual Literacy Association (27th, Chicago, Illinois October 18-22, 1995).

ERIC Educational Resources Information Center

Griffin, Robert E., Ed.; And Others

This document contains 47 selected papers from the 1995 International Visual Literacy Association (IVLA) conference. Topics include: the cultural significance of tombstone iconography; the predicted impact of multimedia on education and entertainment; the effects of digital imaging on the art of photography; visual representation of the structure…

Looking is buying. How visual attention and choice are affected by consumer preferences and properties of the supermarket shelf.

PubMed

Gidlöf, Kerstin; Anikin, Andrey; Lingonblad, Martin; Wallin, Annika

2017-09-01

There is a battle in the supermarket isle, a battle between what the consumer wants and what the retailer and others want her to see, and subsequently to buy. Product packages and displays contain a number of features and attributes tailored to catch consumers' attention. These are what we call external factors comprising the visual saliency, the number of facings, and the placement of each product. But a consumer also brings with her a number of goals and interests related to the products and their attributes. These are important internal factors, including brand preferences, price sensitivity, and dietary inclinations. We fit mobile eye trackers to consumers visiting real-life supermarkets in order to investigate to what extent external and internal factors affect consumers' visual attention and purchases. Both external and internal factors influenced what products consumers looked at, with a strong positive interaction between visual saliency and consumer preferences. Consumers appear to take advantage of visual saliency in their decision making, using their knowledge about products' appearance to guide their visual attention towards those that fit their preferences. When it comes to actual purchases, however, visual attention was by far the most important predictor, even after controlling for all other internal and external factors. In other words, the very act of looking longer or repeatedly at a package, for any reason, makes it more likely that this product will be bought. Visual attention is thus crucial for understanding consumer behaviour, even in the cluttered supermarket environment, but it cannot be captured by measurements of visual saliency alone. Copyright © 2017 Elsevier Ltd. All rights reserved.

Imagery and Visual Literacy: Selected Readings from the Annual Conference of the International Visual Literacy Association (26th, Tempe, Arizona, October 12-16, 1994).

ERIC Educational Resources Information Center

Beauchamp, Darrell G.; And Others

This document contains selected conference papers all relating to visual literacy. The topics include: process issues in visual literacy; interpreting visual statements; what teachers need to know; multimedia presentations; distance education materials for correctional use; visual culture; audio-visual interaction in desktop multimedia; the…

A sensorimotor account of vision and visual consciousness.

PubMed

O'Regan, J K; Noë, A

2001-10-01

Many current neurophysiological, psychophysical, and psychological approaches to vision rest on the idea that when we see, the brain produces an internal representation of the world. The activation of this internal representation is assumed to give rise to the experience of seeing. The problem with this kind of approach is that it leaves unexplained how the existence of such a detailed internal representation might produce visual consciousness. An alternative proposal is made here. We propose that seeing is a way of acting. It is a particular way of exploring the environment. Activity in internal representations does not generate the experience of seeing. The outside world serves as its own, external, representation. The experience of seeing occurs when the organism masters what we call the governing laws of sensorimotor contingency. The advantage of this approach is that it provides a natural and principled way of accounting for visual consciousness, and for the differences in the perceived quality of sensory experience in the different sensory modalities. Several lines of empirical evidence are brought forward in support of the theory, in particular: evidence from experiments in sensorimotor adaptation, visual "filling in," visual stability despite eye movements, change blindness, sensory substitution, and color perception.

[The value of mobilization of the prostatic region via perineal approach in the treatment of ruptures and stenoses of the posterior urethra].

PubMed

L'Hermite, J; Chopin, G; Hubert, J; Six, A; Guillemin, P

1990-01-01

11 cases of end to end anastomosis associated with the mobilization of the prostate is reported. The authors use only the perineal access. The operation is utilised in two circumstances: injuries or traumatic strictures to the membranous urethra. 4 ruptured prostato-membranous urethras with 4 good results. 7 stenosis with 5 good results. 2 recurrences which one of them had a good result with a simple urethrotomy. Complication: no incontinence. 2 cases of impotence are noted. One of them had recovered, the other is secondary of the pelvic fracture. Follow up: mean 3 years (6 months-5 years). our experience suggest that the mobilization of the prostate is an excellent aid to end to end anastomosis. This technique permits the only perineal access.

A description of discrete internal representation schemes for visual pattern discrimination.

PubMed

Foster, D H

1980-01-01

A general description of a class of schemes for pattern vision is outlined in which the visual system is assumed to form a discrete internal representation of the stimulus. These representations are discrete in that they are considered to comprise finite combinations of "components" which are selected from a fixed and finite repertoire, and which designate certain simple pattern properties or features. In the proposed description it is supposed that the construction of an internal representation is a probabilistic process. A relationship is then formulated associating the probability density functions governing this construction and performance in visually discriminating patterns when differences in pattern shape are small. Some questions related to the application of this relationship to the experimental investigation of discrete internal representations are briefly discussed.

Urolume stent placement for the treatment of postbrachytherapy bladder outlet obstruction.

PubMed

Konety, B R; Phelan, M W; O'Donnell, W F; Antiles, L; Chancellor, M B

2000-05-01

Transurethral resection (TURP) or incision of the prostate is generally not effective for treating bladder outlet obstruction after transperineal brachytherapy for prostate cancer. Furthermore, TURP could compromise full-dose effective radiation delivery to the prostate. We analyzed the efficacy of the UroLume stent in treating the urinary outflow obstruction in such patients. Five patients who had undergone brachytherapy (3 with (192)Ir high-dose radiation and 2 with (125)I) subsequently developed one or more episodes of urinary retention 2 weeks to 4 years after treatment. The patients failed or could not tolerate alpha-blockers or clean intermittent catheterization. Three patients subsequently underwent urethral dilation/optical internal urethrotomy for strictures, and 1 patient underwent suprapubic tube placement. Following the failure of these interventions, each of these patients had a UroLume stent placement. A single UroLume stent (2 cm in 3 patients and 2.5 cm in 2 patients) was placed under local/spinal anesthesia. All patients were able to void spontaneously immediately after stent placement. Of the patients with previous urethral strictures, 1 remained continent and 1 had persistent incontinence. Neither of the patients with early postbrachytherapy retention developed incontinence after stent placement. The main complaints following stent placement were referred pain to the head of the penis and dysuria. Stent-related symptoms necessitated stent removal in 2 of 5 patients, 4 to 6 weeks after placement. The UroLume stent can be used as an alternative form of therapy for managing postbrachytherapy bladder outlet obstruction. The treatment is easily reversible by removing the stent when obstruction resolves.

Redo-urethroplasty in pelvic fracture urethral distraction defect: an audit.

PubMed

Bhagat, Suresh K; Gopalakrishnan, Ganesh; Kumar, Santosh; Devasia, Antony; Kekre, Nitin S

2011-02-01

To predict the outcome of redo-urethroplasty after failed single or multiple open urethral procedures for pelvic fracture urethral distraction defects. From January 1997 to December 2006, 43 patients underwent redo-urethroplasty for pelvic fracture urethral distraction defect. Forty-one were referred from other centers. All had undergone open surgery along with an endoscopic procedure (one or more procedures in each patient) which included endoscopic internal urethrotomy, urethral stenting or urethral dilations. There were 43 men with mean age of 29 (range 11-52). Eleven had associated injuries: intraperitoneal bladder rupture (3), bladder neck (2), rectum (3), anal sphincter (2), combined bladder, rectum and anal sphincter (1). Trocar suprapubic cystostomy was performed in 22, rail-road procedures in 10 and open suprapubic cystostomy in 11 along with the management of associated injuries as immediate treatment. Of 43 patients, 28 had progressive perineal, and 12 had transpubic repair. Three patients had total bulbar necrosis, and they underwent prepuceal tube reconstruction (1) and staged substitution with BMG and standard scrotal inlay (2). Analysis of various factors like number of attempts at previous surgery and stricture length did not affect the outcome. A successful result was achieved in 36 (83.72%), improved and stable in five and failure in two. The overall result of redo-urethroplasty for pelvic fracture urethral distraction defect continues to be gratifying. Failures happen usually within the first 3 months. Substitution urethroplasty can be reserved for those who have long distraction defect. Long-term follow-up is essential using stringent criteria to measure success.

Posterior Urethroplasty Complexity and Prognosis Can be Described by a Novel Method: Posterior Urethral Stenosis Score.

PubMed

Wang, Lin; Lv, Xiangguo; Jin, Chongrui; Guo, Hailin; Shu, Huiquan; Fu, Qiang; Sa, Yinglong

2018-02-01

To develop a standardized PU-score (posterior urethral stenosis score), with the goal of using this scoring system as a preliminary predictor of surgical complexity and prognosis of posterior urethral stenosis. We retrospectively reviewed records of all patients who underwent posterior urethral surgery at our institution from 2013 to 2015. The PU-score is based on 5 components, namely etiology (1 or 2 points), location (1-3 points), length (1-3 points), urethral fistula (1 or 2 points), and posterior urethral false passage (1 point). We calculated the score of all patients and analyzed its association with surgical complexity, stenosis recurrence, intraoperative blood loss, erectile dysfunction, and urinary incontinence. There were 144 patients who underwent low complexity urethral surgery (direct vision internal urethrotomy, anastomosis with or without crural separation) with a mean score of 5.1 points, whereas 143 underwent high complexity urethroplasty (anastomosis with inferior pubectomy or urethrorectal fistula repair, perineal or scrotum skin flap urethroplasty, bladder flap urethroplasty) with a mean score of 6.9 points. The increase of PU-score was predictive of higher surgical complexity (P = .000), higher recurrence (P = .002), more intraoperative blood loss (P = .000), and decrease of preoperative (P = .037) or postoperative erectile function (P = .047). However, no association was observed between PU-score and urinary incontinence (P = .213). The PU-score is a novel and meaningful scoring system that describes the essential factors in determining the complexity and prognosis for posterior urethral stenosis. Copyright © 2017. Published by Elsevier Inc.

Preputial skin free graft as dorsal onlay urethroplasty: Our experience of 73 patients.

PubMed

Bapat, Shivadeo S; Padhye, Abhijit S; Yadav, Pushkaraj B; Bhave, Ashish A

2007-10-01

To present the outcome of dorsal onlay urethroplasty in 73 patients for stricture urethra over a period of eight years. Seventy-three patients of stricture urethra have undergone dorsal onlay urethroplasty from July 1998 to February 2006. Age distribution: 14-58 years. Trauma 20/73 (27.39%), Balanitis Xerotica Obliterans 2/73 (2.73%), Iatrogenic 26/73(35.61%), Infection 3/73 (4.10%), Idiopathic 22/73 (30.13%). Site: Penobulbar-25/73, bulbar-38/73, membranous-8/73 and long length-2/73. Suprapubic catheter was inserted preoperatively: 21/73 patients. Preputial / distal penile skin was used in all patients. Buccal mucosa was not used in any patient. Hospitalization was for four to five days. Catheter was removed after 21 days. All patients had their first endoscopic checkup after three months. Subsequently they were followed up by uroflometry. Routine imaging of urethra for follow-up was not carried out. 63/73 (86.30%) patients had satisfactory outcome not requiring any further treatment, 8/73 (10.95%) developed anastomotic stricture (3/8-optical internal urethrotomy, 5/8 dilatation alone). 2/73 (2.75%) developed external meatal stenosis. None had urinary fistula and required repeat urethroplasty. Follow-up ranged from three months to eight years. Dorsal onlay urethroplasty using preputial/distal penile skin is a satisfactory procedure. Preputial/distal penile skin is devoid of hair and fat and hence an ideal graft material. Even in circumscribed patients distal penile skin can be harvested. Long-term follow-up is required in judging results of patients with stricture urethra.

Experience with 32 Pelvic Fracture Urethral Defects Associated with Urethrorectal Fistulas: Transperineal Urethroplasty with Gracilis Muscle Interposition.

PubMed

Guo, Hailin; Sa, Yinglong; Fu, Qiang; Jin, Chongrui; Wang, Lin

2017-07-01

Pelvic fracture urethral defects associated with urethrorectal fistulas are rare and difficult to repair. The aim of this study was to evaluate the efficacy of transperineal urethroplasty with gracilis muscle interposition for the repair of pelvic fracture urethral defects associated with urethrorectal fistulas. We identified 32 patients who underwent transperineal urethroplasty with gracilis muscle interposition to repair pelvic fracture urethral defects associated with urethrorectal fistulas. Patient demographics as well as preoperative, operative and postoperative data were obtained. Mean followup was 33 months (range 6 to 64). The overall success rate was 91% (29 of 32 cases). One-stage repair was successful in 17 of 18 patients (94%) using perineal anastomosis with separation of the corporeal body and in 12 of 14 (86%) using perineal anastomosis with inferior pubectomy and separation of the corporeal body. All 22 patients (100%) without a previous history of repair were successfully treated. However, only 7 of 10 patients (70%) with a previous history of failed urethroplasty and urethrorectal fistula repair were cured. Recurrent urethral strictures developed in 2 cases. One patient was treated successfully with optical internal urethrotomy and the other was treated successfully with tubed perineoscrotal flap urethroplasty. Recurrent urethrorectal fistulas associated with urethral strictures developed in an additional patient. Transperineal urethroplasty with gracilis muscle interposition is a safe and effective surgical procedure for most pelvic fracture urethral defects associated with urethrorectal fistulas. Several other factors may affect its postoperative efficiency. Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Effects of internal limiting membrane peeling during vitrectomy for macula-off primary rhegmatogenous retinal detachment.

PubMed

Blanco-Teijeiro, María José; Bande Rodriguez, Manuel; Mansilla Cuñarro, Raquel; Paniagua Fernández, Laura; Ruiz-Oliva Ruiz, Francisco; Piñeiro Ces, Antonio

2018-03-01

To determine the effectiveness of internal limiting membrane peeling during vitrectomy for macula-off primary rhegmatogenous retinal detachment in the prevention of postoperative epiretinal membrane formation and achievement of good visual outcomes and to identify preoperative and intraoperative risk factors for epiretinal membrane formation. We retrospectively analyzed data from 62 eyes of 62 consecutive patients with macula-off primary rhegmatogenous retinal detachment who underwent vitrectomy with (n = 30) or without (n = 32) internal limiting membrane peeling between January 2014 and March 2016 and were followed up for at least 12 months. The effects of internal limiting membrane peeling on visual outcomes and postoperative recovery of the macular structure were determined. We subsequently divided patients into an epiretinal membrane group and a non-epiretinal membrane group and assessed the effects of various preoperative and intraoperative factors on postoperative epiretinal membrane formation. Postoperative epiretinal membrane developed in 10 patients in the no internal limiting membrane peeling group and three patients in the internal limiting membrane peeling group. Postoperative visual acuity significantly improved in both groups. Epiretinal membrane formation was found to be correlated with a higher number of retinal breaks. Our results suggest that internal limiting membrane peeling during macula-off primary rhegmatogenous retinal detachment surgery can reduce the occurrence of postoperative epiretinal membrane, is safe, and results in favorable visual outcomes.

EDITORIAL: The 14th International Symposium on Flow Visualization, ISFV14 The 14th International Symposium on Flow Visualization, ISFV14

NASA Astrophysics Data System (ADS)

Kim, Kyung Chun; Lee, Sang Joon

2011-06-01

The 14th International Symposium on Flow Visualization (ISFV14) was held in Daegu, Korea, on 21-24 June 2010. There were 304 participants from 17 countries. The state of the art in many aspects of flow visualization was presented and discussed, and a total of 243 papers from 19 countries were presented. Two special lectures and four invited lectures, 48 paper sessions and one poster session were held in five session rooms and in a lobby over four days. Among the paper sessions, those on 'biological flows', 'micro/nano fluidics', 'PIV/PTV' and 'compressible and sonic flows' received great attention from the participants of ISFV14. Special events included presentations of 'The Asanuma Award' and 'The Leonardo Da Vinci Award' to prominent contributors. Awards for photos and movies were given to three scientists for their excellence in flow visualizations. Sixteen papers were selected by the Scientific Committee of ISFV14. After the standard peer review process of this journal, six papers were finally accepted for publication. We wish to thank the editors of MST for making it possible to publish this special feature from ISFV14. We also thank the authors for their careful and insightful work and cooperation in the preparation of revised papers. It will be our pleasure if readers appreciate the hot topics in flow visualization research as a result of this special feature. We also hope that the progress in flow visualization will create new research fields. The 15th International Symposium on Flow Visualization will be held in Minsk, Belarus in 2012. We would like to express sincere thanks to the staff at IOP Publishing for their kind support.

An association between auditory-visual synchrony processing and reading comprehension: Behavioral and electrophysiological evidence

PubMed Central

Mossbridge, Julia; Zweig, Jacob; Grabowecky, Marcia; Suzuki, Satoru

2016-01-01

The perceptual system integrates synchronized auditory-visual signals in part to promote individuation of objects in cluttered environments. The processing of auditory-visual synchrony may more generally contribute to cognition by synchronizing internally generated multimodal signals. Reading is a prime example because the ability to synchronize internal phonological and/or lexical processing with visual orthographic processing may facilitate encoding of words and meanings. Consistent with this possibility, developmental and clinical research has suggested a link between reading performance and the ability to compare visual spatial/temporal patterns with auditory temporal patterns. Here, we provide converging behavioral and electrophysiological evidence suggesting that greater behavioral ability to judge auditory-visual synchrony (Experiment 1) and greater sensitivity of an electrophysiological marker of auditory-visual synchrony processing (Experiment 2) both predict superior reading comprehension performance, accounting for 16% and 25% of the variance, respectively. These results support the idea that the mechanisms that detect auditory-visual synchrony contribute to reading comprehension. PMID:28129060

An Association between Auditory-Visual Synchrony Processing and Reading Comprehension: Behavioral and Electrophysiological Evidence.

PubMed

Mossbridge, Julia; Zweig, Jacob; Grabowecky, Marcia; Suzuki, Satoru

2017-03-01

The perceptual system integrates synchronized auditory-visual signals in part to promote individuation of objects in cluttered environments. The processing of auditory-visual synchrony may more generally contribute to cognition by synchronizing internally generated multimodal signals. Reading is a prime example because the ability to synchronize internal phonological and/or lexical processing with visual orthographic processing may facilitate encoding of words and meanings. Consistent with this possibility, developmental and clinical research has suggested a link between reading performance and the ability to compare visual spatial/temporal patterns with auditory temporal patterns. Here, we provide converging behavioral and electrophysiological evidence suggesting that greater behavioral ability to judge auditory-visual synchrony (Experiment 1) and greater sensitivity of an electrophysiological marker of auditory-visual synchrony processing (Experiment 2) both predict superior reading comprehension performance, accounting for 16% and 25% of the variance, respectively. These results support the idea that the mechanisms that detect auditory-visual synchrony contribute to reading comprehension.

Delayed surgical repair of posttraumatic posterior urethral distraction defects in children and adolescents: long-term results.

PubMed

Podesta, Miguel; Podesta, Miguel

2015-04-01

Various surgical techniques have been proposed to treat pelvic fracture urethral distraction defects (PFUDDs) in children (Figure): primary alignment of the acute transected urethra, substitution procedures and delayed anastomosis urethroplasties (DAU) by perineal, elaborated perineal, transpubic or perineo-abdominal/partial transpubic access. However, long-term follow-up of surgical correction for PFUDDS with DAU is infrequently reported in the literature. Long-term efficacy of DAU in children and adolescents with PFUDDs was evaluated. Other surgical methods used to accomplish tension-free DAU were also described. We reviewed records of 49 male children aged 3.5-17.5 years (median 9.6) with PFUDDS who underwent DAU from 1980 to 2006. Median PFUDDs length was 3 cm (range 2-6). Six patients had prior failed treatments: anastomotic urethroplasties (5) and internal urethrotomy (1). Surgical access was transperineal in 28 cases and perineal/partial pubectomy in 21. Urethral rerouting was performed in 8 cases. Median follow-up was 6.5 years (range 5-22). On review median PFUDDS length in patients treated with primary cystostomy was 3 cm compared to those initially managed with urethral alignment (4 cm). Five patients treated with perineal DAU developed recurrent strictures at the anastomosis site, successfully managed with additional perineal/partial pubectomy anastomosis (4 cases) and internal urethrotomy (1). Primary and overall success rate was 89, 7% and 100%, respectively. Urinary incontinence occurred in 9 cases. Two had overflow incontinence and performed self-catheterization; 1 developed sphincter incontinence and required AUS placement, while 4 of 6 cases with mild stress incontinence achieved dryness at pubertal age. Retrospectively, associated bladder neck lesions at trauma time were noted in 5 patients. Three patients with erectile dysfunction before DAU remained impotent. In children, several factors make management of PFUDDs more difficult than in adults: 1) restricted surgical access to reach a high lying proximal urethral end, 2) long distraction defects, 3) simultaneous bladder neck and membranous urethral lesions and 4) small urethral caliber. In our experience and that of others (Turner Warwick, 1989 and Ranjan, 2012), radiographic and endoscopic findings provide information on stricture features; however, the final choice of surgical exposure to restore urethral continuity is made at operative time based on PFUDD complexity. Perineal exposure usually allows performing DAU in 2 cm long PFUDDs. Ten percent of our patients treated with perineal DAU developed recurrent strictures attributed to inappropriate access selection or unrecognized PFUDD complexity. Failures were treated endoscopically (1) and by perineal/partial pubectomy anastomotic urethroplasty (4) with 100% final success. We used perineal/partial pubectomy DAU in 43% of the cases to excise pelvic scarring and bridge long urethral gaps, with urethral rerouting in 8 cases. Success rate of initial perineal and perineal/partial pubectomy anastomotic procedures was 82% and 100%, respectively. Koraitim (1997), Orabi (2008) and Ranjan (2012) reported excellent outcomes in children with either transperineal or transpubic anastomotic repair, as opposed to poor results in those undergoing substitution urethroplaties. Most reports rarely evaluate urinary incontinence after successful DAU. At the end of follow-up only 2 of our 9 initial incontinent cases remain with acceptable stress incontinence. Retrospectively, in 5 cases the original trauma comprised the bladder neck and the membranous sphincter mechanism. In our series erectile dysfunction after trauma did not change after DAU except in 1 patient who regained potency 1 year after repair. All patients were referred after initial treatment was done elsewhere, thus they may represent the most severe PFUDDs cases. Additionally, erection dysfunction was not investigated in the kind of detail required due to patients' age. DAU has durable success rate for PFUDDs treatment in children with a healthy bulbar urethra. In childhood, additional surgical steps are frequently needed to achieve direct anastomotic repair. Copyright © 2015 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Neck/shoulder discomfort due to visually demanding experimental near work is influenced by previous neck pain, task duration, astigmatism, internal eye discomfort and accommodation

PubMed Central

Forsman, Mikael; Richter, Hans O.

2017-01-01

Visually demanding near work can cause eye discomfort, and eye and neck/shoulder discomfort during, e.g., computer work are associated. To investigate direct effects of experimental near work on eye and neck/shoulder discomfort, 33 individuals with chronic neck pain and 33 healthy control subjects performed a visual task four times using four different trial lenses (referred to as four different viewing conditions), and they rated eye and neck/shoulder discomfort at baseline and after each task. Since symptoms of eye discomfort may differ depending on the underlying cause, two categories were used; internal eye discomfort, such as ache and strain, that may be caused by accommodative or vergence stress; and external eye discomfort, such as burning and smarting, that may be caused by dry-eye disorders. The cumulative performance time (reflected in the temporal order of the tasks), astigmatism, accommodation response and concurrent symptoms of internal eye discomfort all aggravated neck/shoulder discomfort, but there was no significant effect of external eye discomfort. There was also an interaction effect between the temporal order and internal eye discomfort: participants with a greater mean increase in internal eye discomfort also developed more neck/shoulder discomfort with time. Since moderate musculoskeletal symptoms are a risk factor for more severe symptoms, it is important to ensure a good visual environment in occupations involving visually demanding near work. PMID:28832612

Neck/shoulder discomfort due to visually demanding experimental near work is influenced by previous neck pain, task duration, astigmatism, internal eye discomfort and accommodation.

PubMed

Zetterberg, Camilla; Forsman, Mikael; Richter, Hans O

2017-01-01

Visually demanding near work can cause eye discomfort, and eye and neck/shoulder discomfort during, e.g., computer work are associated. To investigate direct effects of experimental near work on eye and neck/shoulder discomfort, 33 individuals with chronic neck pain and 33 healthy control subjects performed a visual task four times using four different trial lenses (referred to as four different viewing conditions), and they rated eye and neck/shoulder discomfort at baseline and after each task. Since symptoms of eye discomfort may differ depending on the underlying cause, two categories were used; internal eye discomfort, such as ache and strain, that may be caused by accommodative or vergence stress; and external eye discomfort, such as burning and smarting, that may be caused by dry-eye disorders. The cumulative performance time (reflected in the temporal order of the tasks), astigmatism, accommodation response and concurrent symptoms of internal eye discomfort all aggravated neck/shoulder discomfort, but there was no significant effect of external eye discomfort. There was also an interaction effect between the temporal order and internal eye discomfort: participants with a greater mean increase in internal eye discomfort also developed more neck/shoulder discomfort with time. Since moderate musculoskeletal symptoms are a risk factor for more severe symptoms, it is important to ensure a good visual environment in occupations involving visually demanding near work.

Development of internal models and predictive abilities for visual tracking during childhood

PubMed Central

Ego, Caroline; Yüksel, Demet

2015-01-01

The prediction of the consequences of our own actions through internal models is an essential component of motor control. Previous studies showed improvement of anticipatory behaviors with age for grasping, drawing, and postural control. Since these actions require visual and proprioceptive feedback, these improvements might reflect both the development of internal models and the feedback control. In contrast, visual tracking of a temporarily invisible target gives specific markers of prediction and internal models for eye movements. Therefore, we recorded eye movements in 50 children (aged 5–19 yr) and in 10 adults, who were asked to pursue a visual target that is temporarily blanked. Results show that the youngest children (5–7 yr) have a general oculomotor behavior in this task, qualitatively similar to the one observed in adults. However, the overall performance of older subjects in terms of accuracy at target reappearance and variability in their behavior was much better than the youngest children. This late maturation of predictive mechanisms with age was reflected into the development of the accuracy of the internal models governing the synergy between the saccadic and pursuit systems with age. Altogether, we hypothesize that the maturation of the interaction between smooth pursuit and saccades that relies on internal models of the eye and target displacement is related to the continuous maturation of the cerebellum. PMID:26510757

Development of internal models and predictive abilities for visual tracking during childhood.

PubMed

Ego, Caroline; Yüksel, Demet; Orban de Xivry, Jean-Jacques; Lefèvre, Philippe

2016-01-01

The prediction of the consequences of our own actions through internal models is an essential component of motor control. Previous studies showed improvement of anticipatory behaviors with age for grasping, drawing, and postural control. Since these actions require visual and proprioceptive feedback, these improvements might reflect both the development of internal models and the feedback control. In contrast, visual tracking of a temporarily invisible target gives specific markers of prediction and internal models for eye movements. Therefore, we recorded eye movements in 50 children (aged 5-19 yr) and in 10 adults, who were asked to pursue a visual target that is temporarily blanked. Results show that the youngest children (5-7 yr) have a general oculomotor behavior in this task, qualitatively similar to the one observed in adults. However, the overall performance of older subjects in terms of accuracy at target reappearance and variability in their behavior was much better than the youngest children. This late maturation of predictive mechanisms with age was reflected into the development of the accuracy of the internal models governing the synergy between the saccadic and pursuit systems with age. Altogether, we hypothesize that the maturation of the interaction between smooth pursuit and saccades that relies on internal models of the eye and target displacement is related to the continuous maturation of the cerebellum. Copyright © 2016 the American Physiological Society.

Visual Discourse in Scientific Conference Papers: A Genre-based Study.

ERIC Educational Resources Information Center

Rowley-Jolivet, Elizabeth

2002-01-01

Investigates the role of visual communication in a spoken research genre: the scientific research paper. Analyzes 2,048 visuals projected during 90 papers given at five international conferences in three fields (Geology, medicine, physics), in order to bring out the recurrent features of the visual dimension. (Author/VWL)

SURGICAL OUTCOMES IN PATIENTS WITH MACULAR PUCKER AND GOOD PREOPERATIVE VISUAL ACUITY AFTER VITRECTOMY WITH MEMBRANE PEELING.

PubMed

Reilly, Gayatri; Melamud, Alexander; Lipscomb, Peter; Toussaint, Brian

2015-09-01

To evaluate whether patients with macular pucker (epiretinal membrane [ERM]) and good preoperative visual acuity (20/50 or better) benefit from small-gauge pars plana vitrectomy with membrane peeling. Retrospective chart review of eyes undergoing small-gauge pars plana vitrectomy for ERM. Inclusion criterion was impaired visual acuity (20/50 or better) due to ERM. Exclusion criteria were preoperative visual acuity of 20/60 or worse, previous surgery (other than uncomplicated cataract surgery), and any documented evidence of macular or corneal disease that would limit visual potential. The main outcome measure was final visual acuity. Secondary outcomes included the role of internal limiting membrane peeling, and the effect of preoperative cystoid macular edema and internal limiting membrane peeling on visual acuity. One hundred and forty eyes met inclusion criteria of which 94% underwent 25-gauge vitrectomy (remainder had 23-gauge). There was a statistically significant improvement in final vision with the mean preoperative visual acuity of 0.305 logMAR (20/40) and 1-year visual acuity of 0.250 logMAR (20/35) (P = 0.0167). Cataract formation in phakic patients had a significant effect on the final visual outcome. Fifty-six of 63 patients (89%) in the phakic cohort developed a visually significant cataract by study end. The mean time to recommendation of cataract surgery was 8.4 months. Thirty-eight eyes (27%) had preoperative cystoid macular edema. Fifty-nine eyes (42%) underwent internal limiting membrane peeling. Neither one of these secondary outcome measures had a significant effect on the final visual outcome. Pars plana vitrectomy is both efficacious and safe an option for patients with ERMs and good preoperative vision. Eyes with an ERM and vision 20/50 or better had a statistically significant improvement in the final visual outcome after small-gauge pars plana vitrectomy surgery. As with large-gauge vitrectomy, cataract formation occurred in most phakic eyes within the first year after surgery.

Resource-sharing between internal maintenance and external selection modulates attentional capture by working memory content.

PubMed

Kiyonaga, Anastasia; Egner, Tobias

2014-01-01

It is unclear why and under what circumstances working memory (WM) and attention interact. Here, we apply the logic of the time-based resource-sharing (TBRS) model of WM (e.g., Barrouillet et al., 2004) to explore the mixed findings of a separate, but related, literature that studies the guidance of visual attention by WM contents. Specifically, we hypothesize that the linkage between WM representations and visual attention is governed by a time-shared cognitive resource that alternately refreshes internal (WM) and selects external (visual attention) information. If this were the case, WM content should guide visual attention (involuntarily), but only when there is time for it to be refreshed in an internal focus of attention. To provide an initial test for this hypothesis, we examined whether the amount of unoccupied time during a WM delay could impact the magnitude of attentional capture by WM contents. Participants were presented with a series of visual search trials while they maintained a WM cue for a delayed-recognition test. WM cues could coincide with the search target, a distracter, or neither. We varied both the number of searches to be performed, and the amount of available time to perform them. Slowing of visual search by a WM matching distracter-and facilitation by a matching target-were curtailed when the delay was filled with fast-paced (refreshing-preventing) search trials, as was subsequent memory probe accuracy. WM content may, therefore, only capture visual attention when it can be refreshed, suggesting that internal (WM) and external attention demands reciprocally impact one another because they share a limited resource. The TBRS rationale can thus be applied in a novel context to explain why WM contents capture attention, and under what conditions that effect should be observed.

Resource-sharing between internal maintenance and external selection modulates attentional capture by working memory content

PubMed Central

Kiyonaga, Anastasia; Egner, Tobias

2014-01-01

It is unclear why and under what circumstances working memory (WM) and attention interact. Here, we apply the logic of the time-based resource-sharing (TBRS) model of WM (e.g., Barrouillet et al., 2004) to explore the mixed findings of a separate, but related, literature that studies the guidance of visual attention by WM contents. Specifically, we hypothesize that the linkage between WM representations and visual attention is governed by a time-shared cognitive resource that alternately refreshes internal (WM) and selects external (visual attention) information. If this were the case, WM content should guide visual attention (involuntarily), but only when there is time for it to be refreshed in an internal focus of attention. To provide an initial test for this hypothesis, we examined whether the amount of unoccupied time during a WM delay could impact the magnitude of attentional capture by WM contents. Participants were presented with a series of visual search trials while they maintained a WM cue for a delayed-recognition test. WM cues could coincide with the search target, a distracter, or neither. We varied both the number of searches to be performed, and the amount of available time to perform them. Slowing of visual search by a WM matching distracter—and facilitation by a matching target—were curtailed when the delay was filled with fast-paced (refreshing-preventing) search trials, as was subsequent memory probe accuracy. WM content may, therefore, only capture visual attention when it can be refreshed, suggesting that internal (WM) and external attention demands reciprocally impact one another because they share a limited resource. The TBRS rationale can thus be applied in a novel context to explain why WM contents capture attention, and under what conditions that effect should be observed. PMID:25221499

Contextual signals in visual cortex.

PubMed

Khan, Adil G; Hofer, Sonja B

2018-06-05

Vision is an active process. What we perceive strongly depends on our actions, intentions and expectations. During visual processing, these internal signals therefore need to be integrated with the visual information from the retina. The mechanisms of how this is achieved by the visual system are still poorly understood. Advances in recording and manipulating neuronal activity in specific cell types and axonal projections together with tools for circuit tracing are beginning to shed light on the neuronal circuit mechanisms of how internal, contextual signals shape sensory representations. Here we review recent work, primarily in mice, that has advanced our understanding of these processes, focusing on contextual signals related to locomotion, behavioural relevance and predictions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Representation of visual gravitational motion in the human vestibular cortex.

PubMed

Indovina, Iole; Maffei, Vincenzo; Bosco, Gianfranco; Zago, Myrka; Macaluso, Emiliano; Lacquaniti, Francesco

2005-04-15

How do we perceive the visual motion of objects that are accelerated by gravity? We propose that, because vision is poorly sensitive to accelerations, an internal model that calculates the effects of gravity is derived from graviceptive information, is stored in the vestibular cortex, and is activated by visual motion that appears to be coherent with natural gravity. The acceleration of visual targets was manipulated while brain activity was measured using functional magnetic resonance imaging. In agreement with the internal model hypothesis, we found that the vestibular network was selectively engaged when acceleration was consistent with natural gravity. These findings demonstrate that predictive mechanisms of physical laws of motion are represented in the human brain.

Lida Cochran, Matriarch of Visual Literacy

ERIC Educational Resources Information Center

Davis, Harry

2009-01-01

In this article, the author describes the life and works of Lida Cochran, the matriarch of visual literacy. Lida was practicing "visual literacy" long before there was an association devoted to it. Lida has worked with the AECT, ECT Foundation (the Cochran Internship is named for her husband, Lee Cochran), and the International Visual Literacy…

Asian North-American Children's Literature about the Internment: Visualizing and Verbalizing the Traumatic "Thing"

ERIC Educational Resources Information Center

Chen, Fu-jen; Yu, Su-lin

2006-01-01

Examining six texts about the traumatic experience of the internment either in Canada or the United States during World War II, we focus not only on their stylistic shift from visualization to verbalization as targeted ages of readers increase, but also on the effects, both historical and personal, social and domestic, on children of their…

Decay detection in red oak trees using a combination of visual inspection, acoustic testing, and resistance microdrilling

Treesearch

Xiping Wang; R. Bruce Allison

2008-01-01

Arborists are often challenged to identify internal structural defects hidden from view within tree trunks. This article reports the results of a study using a trunk inspection protocol combining visual observation, single-path stress wave testing, acoustic tomography, and resistance microdrilling to detect internal defects. Two century-old red oak (Quercus rubra)...

An Inventory of International Clearing House Services in Population/Family Planning With Special Reference to Audio-Visual Aids and Educational Materials.

ERIC Educational Resources Information Center

Radel, David

This paper provides an inventory and summary of current and planned international information clearing house services in the field of population/family planning, worldwide. Special emphasis is placed on services relating to audio-visual aids, educational materials, and information/education/communication support, as these items and activities have…

Direct Surgery of Previously Coiled Large Internal Carotid Ophthalmic Aneurysm for the Purpose of Optic Nerve Decompression

PubMed Central

Kawabata, Shuhei; Toyota, Shingo; Kumagai, Tetsuya; Goto, Tetsu; Mori, Kanji; Taki, Takuyu

2017-01-01

Background Progressive visual loss after coil embolization of a large internal carotid ophthalmic aneurysm has been widely reported. It is generally accepted that the primary strategy for this complication should be conservative, including steroid therapy; however, it is not well known as to what approach to take when the conservative therapy is not effective. Case Presentation We report a case of a 55-year-old female presenting with progressive visual loss after the coiling of a ruptured large internal carotid ophthalmic aneurysm. As the conservative therapy had not been effective, we performed neck clipping of the aneurysm with optic canal unroofing, anterior clinoidectomy, and partial removal of the embolized coils for the purpose of optic nerve decompression. After the surgery, the visual symptom was improved markedly. Conclusions It is suggested that direct surgery for the purpose of optic nerve decompression may be one of the options when conservative therapy is not effective for progressive visual disturbance after coil embolization. PMID:28229036

Perceptual Factors Influence Visual Search for Meaningful Symbols In Individuals with Intellectual Disabilities and Down Syndrome or Autism Spectrum Disorders

PubMed Central

Wilkinson, Krista M.; McIlvane, William J.

2013-01-01

Augmentative and alternative communication (AAC) systems often supplement oral communication of individuals with intellectual and communication disabilities. Research with nondisabled preschoolers has demonstrated that two visual perceptual factors influence speed and/or accuracy of finding a target - the internal color and spatial organization of symbols. Twelve participants with Down syndrome and 12 with ASD underwent two search tasks. In one, the symbols were clustered by internal color; in the other the identical symbols had no arrangement cue. Visual search was superior in participants with ASD compared to those with Down syndrome. In both groups, responses were significantly faster when the symbols were clustered by internal color. Construction of aided AAC displays may benefit from attention to their physical/perceptual features. PMID:24245729

Multi-institutional Outcomes of Endoscopic Management of Stricture Recurrence after Bulbar Urethroplasty.

PubMed

Sukumar, Shyam; Elliott, Sean P; Myers, Jeremy B; Voelzke, Bryan B; Smith, Thomas G; Carolan, Alexandra Mc; Maidaa, Michael; Vanni, Alex J; Breyer, Benjamin N; Erickson, Bradley A

2018-05-03

Approximately 10-20% of patients will have a recurrence after urethroplasty. Initial management of these recurrences is often with urethral dilation (UD) or direct vision internal urethrotomy (DVIU). In the current study, we describe outcomes of endoscopic management of stricture recurrence after bulbar urethroplasty. We retrospectively reviewed bulbar urethroplasty data from 5 surgeons from the Trauma and Urologic Reconstruction Network of Surgeons. Men who underwent UD or DVIU for urethroplasty recurrence were identified. Recurrence was defined as inability to pass a 17Fr cystoscope through the area of reconstruction. The primary outcome was the success rate of recurrence management. Comparisons were made between UD and DVIU and then between endoscopic management of recurrences after excision and primary anastomosis urethroplasty (EPA) versus substitutional repairs using time-to-event statistics. There were 53 men with recurrence that were initially managed endoscopically. Median time to urethral stricture recurrence after urethroplasty was noted to be 5 months. At a median follow-up of 5 months, overall success was 42%. Success after UD (n=1/10, 10%) was significantly lower than after DVIU (n=21/43, 49%; p < 0.001) with a hazard ratio of failure of 3.15 (p=0.03). DVIU was more effective after substitutional failure than after EPA (53% vs.13%, P=0.005). DVIU is more successful than UD in the management of stricture recurrence after bulbar urethroplasty. DVIU is more successful for patients with a recurrence after a substitution urethroplasty compared to after EPA, perhaps indicating a different mechanism of recurrence for EPA (ischemic) versus substitution urethroplasty (non-ischemic). Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Urethral stricture vaporization with the KTP laser provides evidence for a favorable impact of laser surgery on wound healing

NASA Astrophysics Data System (ADS)

Schmidlin, Franz R.; Venzi, Giordano; Jichlinski, Patrice; Oswald, Michael; Delacretaz, Guy P.; Gabbiani, Giulio; Leisinger, Hans-Juerg; Graber, Peter

1997-12-01

The objective of this study was to evaluate and compare the safety and efficacy of the KTP 532 laser to direct vision internal urethrotomy (DVIU) in the management of urethral strictures. A total of 32 patients were randomized prospectively in this study, 14 DVIU and 18 KTP 532 laser. Patients were evaluated postoperatively with flowmetry and in the case of recurrence with cystourethrography at 3, 12, 24 weeks. With the KTP 532 laser complete symptomatic and uredynamic success was achieved in 15 (83%) patients at 12 and 24 weeks. Success rate was lower in the DVIU group with 9 (64%) patients at 12 weeks and 8 (57%) patients at 24 weeks. Mean preoperative peak-flow was improved from 6 cc/s to 20 cc/s at 3, 12 and 24 weeks with the KTP laser. With DVIU mean preoperative peak-flow was improved from 5.5 cc/s to 20 cc/s at 3 weeks followed by a steady decrease to 13 cc/s at 12 weeks and to 12 cc/s 24 weeks. No complication was observed in either group of patients. Our results confirm that stricture vaporization with the KTP 532 laser is a safe and efficient procedure. The better results after laser surgery make it also a valuable alternative in the endoscopic treatment of urethral strictures. These findings suggest a favorable influence of laser surgery on wound healing with less wound contraction and scarring. The lack of contraction of laser wounds might be related to the absence and the lack of organization of myofibroblasts in laser induced lesions.

High Regional Variation in Urethroplasty in the United States

PubMed Central

Figler, Bradley D.; Gore, John L.; Holt, Sarah K.; Voelzke, Bryan B.; Wessells, Hunter

2015-01-01

Purpose We identified clinical and regional factors associated with the use of urethroplasty vs repeat endoscopic management for urethral stricture disease. Materials and Methods We analyzed claims for patients 18 to 65 years old in the 2007 to 2011 MarketScan ® Commercial Claims and Encounters Database with a diagnosis of urethral stricture. The primary outcome was treatment with urethroplasty vs repeat endoscopic management, defined as more than 2 dilations or direct vision internal urethrotomies. The likelihood of urethroplasty vs repeat endoscopic management was determined for each major metropolitan area in the United States. Multivariate logistic regression was done to identify factors associated with urethroplasty. Results We identified 41,056 patients with urethral stricture, yielding a diagnosis rate of 296/100,000 men in MarketScan. Repeat endoscopic management and urethroplasty were performed in 2,700 and 1,444 patients, respectively. Compared to patients treated with repeat endoscopic management those with urethroplasty were younger (median age 44 vs 54 years) and more likely to have a Charlson comorbidity score of 0 (84% vs 77%), have traveled out of a metropolitan area for care (34% vs 17%) and have a reconstructive urologist in the treatment metropolitan area (76% and 62%, each p < 0.001). When controlling for age and Charlson comorbidity score, travel out of a metropolitan area (OR 2.7, 95% CI 2.2–3.3) and a reconstructive urologist in the treatment metropolitan area (OR 2.0, 95% CI 1.7–2.5) were associated with a greater likelihood of urethroplasty vs repeat endoscopic management. Conclusions Despite the well established benefits of urethroplasty compared to repeat endoscopic management a strong bias for repeat endoscopic management exists in many regions in the United States. PMID:25072180

History and evolution of dorsal onlay urethroplasty for bulbar urethral stricture repair using skin or buccal mucosal grafts.

PubMed

Barbagli, G; Lazzeri, M

2007-01-01

OBJECTIVES. To illustrate the history and the evolution over time of bulbar dorsal onlay urethroplasty, comparing outcomes when using buccal mucosa or skin grafts. MATERIALS AND METHODS. Ninety-four patients underwent bulbar urethral reconstruction using two dorsal onlay techniques, namely augmented anastomotic urethroplasty and dorsal onlay graft urethroplasty. Preoperative evaluation included clinical history, physical examination, urine culture, residual urine measurement, uroflowmetry and urethrography. Thirty-four patients underwent augmented anastomotic urethroplasty using penile skin (10 cases) or buccal mucosa (24 cases) grafts. Sixty patients underwent dorsal onlay graft urethroplasty using penile skin (38 cases) or buccal mucosa (22 cases) grafts. Forty-eight out of 94 patients received skin grafts and 46 buccal mucosal grafts. RESULTS. Sixty-four (68%) out of 94 cases were successful, whereas 30 (32%) failed. The 34 augmented anastomotic urethroplasties provided successful outcomes in 24 cases (70.6%), but poor outcomes in 10 (29.4%) cases. The 60 dorsal onlay graft urethroplasty proved to be successful in 42 cases (70%), failing in 18 (30%) cases. Twenty-eight (58.3%) out of 48 penile skin grafts were successful and 20 (41.7%) failed. Thirty-six (78.3%) out of 46 buccal mucosa grafts were successful and 10 (21.7%) failed. The 30 failed cases were then treated with internal urethrotomy in 14 cases (46.7%), perineal urethrostomy in 8 cases (26.7%), two-stage repair in 4 cases (13.3%), and one-stage repair in 4 cases (13.3%). CONCLUSIONS. The dorsal onlay technique used for bulbar urethral stricture repair has changed over time. In our experience, the buccal mucosa seems to be the best substitute graft material for bulbar urethroplasty using dorsal approach.

Salvage hypospadias repairs

PubMed Central

Sripathi, V.; Satheesh, M.; Shubha, K.

2008-01-01

Aim: Review of our experience and to develop an algorithm for salvage procedures in the management of hypospadias cripples and treatment of urethral strictures following hypospadias repair. Methods: This is a retrospective review of hypospadias surgeries over a 41-month period. Out of a total 168 surgeries, 20 were salvage/re-operative repairs. In three children a Duplay repair was feasible, while in four others a variety of single-stage repairs could be done. The repair was staged in seven children – buccal mucosal grafts (BMGs) in five, buccal mucosal tube in one, and skin graft in one. Five children with dense strictures were managed by dorsal BMG inlay grafting in one, vascularized tunical onlay grafting on the ventrum in one, and a free tunical patch in one. Three children were treated by internal urethrotomy and stenting for four weeks with a poor outcome. Results: The age of children ranged from 1.5–15 years (mean 4.5). Follow-up ranged from 3 months to 3.5 years. Excellent results were obtained in 10 children (50%) with a well-surfaced erect penis and a slit-like meatus. Glans closure could not be achieved and meatus was coronal in three. Two children developed fistulae following a Duplay repair and following a staged BMG. Three repairs failed completely – a composite repair broke down, a BMG tube stenosed with a proximal leak, and a stricture recurred with loss of a ventral free tunical graft. Conclusions: In salvage procedures performed on hypospadias cripples, a staged repair with buccal mucosa as an inlay in the first stage followed by tubularization 4–6 months later provides good results. A simple algorithm to plan corrective surgery in failed hypospadias cases and obtain satisfactory results is devised. PMID:20011495

Salvage hypospadias repairs.

PubMed

Sripathi, V; Satheesh, M; Shubha, K

2008-10-01

Review of our experience and to develop an algorithm for salvage procedures in the management of hypospadias cripples and treatment of urethral strictures following hypospadias repair. This is a retrospective review of hypospadias surgeries over a 41-month period. Out of a total 168 surgeries, 20 were salvage/re-operative repairs. In three children a Duplay repair was feasible, while in four others a variety of single-stage repairs could be done. The repair was staged in seven children - buccal mucosal grafts (BMGs) in five, buccal mucosal tube in one, and skin graft in one. Five children with dense strictures were managed by dorsal BMG inlay grafting in one, vascularized tunical onlay grafting on the ventrum in one, and a free tunical patch in one. Three children were treated by internal urethrotomy and stenting for four weeks with a poor outcome. The age of children ranged from 1.5-15 years (mean 4.5). Follow-up ranged from 3 months to 3.5 years. Excellent results were obtained in 10 children (50%) with a well-surfaced erect penis and a slit-like meatus. Glans closure could not be achieved and meatus was coronal in three. Two children developed fistulae following a Duplay repair and following a staged BMG. Three repairs failed completely - a composite repair broke down, a BMG tube stenosed with a proximal leak, and a stricture recurred with loss of a ventral free tunical graft. In salvage procedures performed on hypospadias cripples, a staged repair with buccal mucosa as an inlay in the first stage followed by tubularization 4-6 months later provides good results. A simple algorithm to plan corrective surgery in failed hypospadias cases and obtain satisfactory results is devised.

Objective functional visual outcomes of cataract surgery in patients with good preoperative visual acuity

PubMed Central

Zhu, X; Ye, H; He, W; Yang, J; Dai, J; Lu, Y

2017-01-01

Purpose To explore the objective functional visual outcomes of cataract surgery in patients with good preoperative visual acuity. Methods We enrolled 130 cataract patients whose best-corrected visual acuity (BCVA) was 20/40 or better preoperatively. Objective visual functions were evaluated with a KR-1W analyzer before and at 1 month after cataract surgery. Results The nuclear (N), cortical (C), and N+C groups had very high preoperative ocular and internal total high-order aberrations (HOAs), coma, and abnormal spherical aberrations. At 1 month after cataract surgery, in addition to the remarkable increase of both uncorrected visual acuity and BCVA, both ocular and internal HOAs in the three groups decreased significantly after cataract surgery (all P<0.05). Point spread function and modulation transfer functions were also improved significantly in these patients (all P<0.05). Conclusions The objective functional vision of patients with 20/40 or better preoperative BCVA improved significantly after cataract surgery. This finding shows that the arbitrary threshold of BCVA worse than 20/40 in China cannot always be used to determine who will benefit from cataract surgery. PMID:27858933

Double inlay plus ventral onlay buccal mucosa graft for simultaneous penile and bulbar urethral stricture.

PubMed

Favorito, Luciano A; Conte, Paulo P; Sobrinho, Ulisses G; Martins, Rodrigo G; Accioly, Tomas

2017-11-17

Buccal mucosa grafts and fascio-cutaneous flaps are frequently used in long anterior urethral strictures (1). The inlay and onlay buccal mucosa grafts are easier to perform, do not need urethral mobilization and generally have good long-term results (2-4). In the present video, we present a case where we used a double buccal mucosa graft technique in a simultaneous penile and bulbar urethral stricture. A 54 year-old male patient was submitted to appendectomy where a urethral catheter was used for two days in May 2015. Three months after surgery, the patient complained of acute urinary retention and a supra-pubic tube was indicated. Urethrocystography was performed two weeks later and showed strictures in penile and bulbar urethra with 3.5 cm and 3 cm in length respectively. Urethroplasty was proposed for the surgical treatment in this case. We used a perineal approach with a ventral sagittal urethrotomy in both strictures. Penile urethra stricture measuring 3.5 cm in length was observed and a free graft from the buccal mucosa was harvested and placed into the longitudinal incision in the dorsal urethra and fixed with interrupted suture as dorsal inlay. Bulbar urethra stricture measuring 3 cm was observed and a free graft from the buccal mucosa was harvested and placed into the longitudinal incision in the ventral urethra and fixed with interrupted suture as ventral onlay. The ventral urethrotomy was closed over a 16Fr Foley catheter and the skin incision was then closed in layers. No intraoperative or postoperative complications occurred. The patient could achieve satisfactory voiding and no complication was seen during the six-month follow-up. Postoperative imaging demonstrated a widely patent urethra, and the mean peak flow was 12 mL/s. The BMG placement can be ventral, dorsal, lateral or combined dorsal and ventral BMG in the meeting of stricture but the first two are most common (5, 6). Ventral location provides the advantages of ease of exposure and good vascular supply by avoiding circumferential rotation of the urethra (7). Early success rates of dorsal and ventral onlay with BMG were 96 and 85%, respectively. However, long-term follow-up revealed essentially no difference in success rates (8-11). Anterior urethral stricture treatments are various, and comprehensive consideration should be given in selecting individualized treatment programs, which must be combined with the patient's stricture, length, complexity, and other factors. Traditionally, anastomotic procedures with transection and urethral excision are suggested for short bulbar strictures, while longer strictures are treated by patch graft urethroplasty preferably using the buccal mucosa as gold-standard material due to its histological characteristics. The current management for complex urethral strictures commonly uses open reconstruction with buccal mucosa urethroplasty. However, there are multiple situations whereby buccal mucosa is inadequate (pan-urethral stricture or prior buccal harvest) or inappropriate for utilization (heavy tobacco use or oral radiation). Multiple options exist for use as alternatives or adjuncts to buccal mucosa in complex urethral strictures (injectable antifibrotic agents, augmentation urethroplasty with skin flaps, lingual mucosa, colonic mucosa, and new developments in tissue engineering for urethral graft material). In the present case, our patient had two strictures and we chose to correct the first stricture with a dorsal graft and the bulbar stricture with a ventral graft because of our personal expertise. We can conclude that the double buccal mucosa graft is easier to perform and can be an option to repair multiple urethral strictures. Copyright® by the International Brazilian Journal of Urology.

A Study on the Visualization Skills of 6th Grade Students

ERIC Educational Resources Information Center

Özkan, Ayten; Arikan, Elif Esra; Özkan, Erdogan Mehmet

2018-01-01

Visualization is an effective method for students to internalize concepts and to establish correlations between concepts. Visualization method is especially more important in mathematics which is perceived as the combination of abstract concepts. In this study, whether 6th grade students can solve questions about "Fractions" by using…

Investigating Visual Literacy: Selected Readings from the Annual Conference of the International Visual Literacy Association (22nd, Bloomington/Normal, Illinois, October 1990).

ERIC Educational Resources Information Center

Beauchamp, Darrell G., Ed.; And Others

This volume contains 53 articles grouped under five headings: (1) Research (14 papers on such topics as cognitive style and cognitive strategies, visual literacy training, and the impact of diagrams, type styles, and computer graphics on learning); (2) Theory (nine papers on such topics as the development of visual literacy concepts, cognition and…

Pars Plana Vitrectomy with Internal Limiting Membrane Peeling for Nontractional Diabetic Macular Edema.

PubMed

Ulrich, Jan Niklas

2017-01-01

Diabetes mellitus remains the leading cause of blindness among working age Americans with diabetic macular edema being the most common cause for moderate and severe vision loss. To investigate the anatomical and visual benefits of pars plana vitrectomy with inner limiting membrane peeling in patients with nontractional diabetic macular edema as well as correlation of integrity of outer retinal layers on spectral domain optical coherence tomography to visual outcomes. We retrospectively reviewed the charts of 42 diabetic patients that underwent vitrectomy with internal limiting membrane peeling for nontractional diabetic macula edema. The integrity of outer retinal layers was evaluated and preoperative central macular thickness and visual acuity were compared with data at 1 month, 3 months and 6 months postoperatively. The student t-test was used to compare the groups. 31 eyes were included. While no differences were seen at 1 and 3 months, there was significant improvement of both central macular thickness and visual acuity at the 6 months follow up visit compared to preoperatively (357, 427 microns; p=0.03. 20/49, 20/82; p=0.03) . Patients with intact external limiting membrane and ellipsoid zone had better preoperative vision than patients with outer retinal layer irregularities (20/54, 20/100; p=0.03) and greater visual gains postoperatively (20/33, p<0.001 versus 20/81; p=non-significant). Pars plana vitrectomy with internal limiting membrane peeling can improve retinal anatomy and visual acuity in patients with nontractional diabetic macular edema. Spectral domain optical coherence tomography may help identify patients with potential for visual improvement.

Internal model of gravity for hand interception: parametric adaptation to zero-gravity visual targets on Earth.

PubMed

Zago, Myrka; Lacquaniti, Francesco

2005-08-01

Internal model is a neural mechanism that mimics the dynamics of an object for sensory motor or cognitive functions. Recent research focuses on the issue of whether multiple internal models are learned and switched to cope with a variety of conditions, or single general models are adapted by tuning the parameters. Here we addressed this issue by investigating how the manual interception of a moving target changes with changes of the visual environment. In our paradigm, a virtual target moves vertically downward on a screen with different laws of motion. Subjects are asked to punch a hidden ball that arrives in synchrony with the visual target. By using several different protocols, we systematically found that subjects do not develop a new internal model appropriate for constant speed targets, but they use the default gravity model and reduce the central processing time. The results imply that adaptation to zero-gravity targets involves a compression of temporal processing through the cortical and subcortical regions interconnected with the vestibular cortex, which has previously been shown to be the site of storage of the internal model of gravity.

Saccadic Corollary Discharge Underlies Stable Visual Perception

PubMed Central

Berman, Rebecca A.; Joiner, Wilsaan M.; Wurtz, Robert H.

2016-01-01

Saccadic eye movements direct the high-resolution foveae of our retinas toward objects of interest. With each saccade, the image jumps on the retina, causing a discontinuity in visual input. Our visual perception, however, remains stable. Philosophers and scientists over centuries have proposed that visual stability depends upon an internal neuronal signal that is a copy of the neuronal signal driving the eye movement, now referred to as a corollary discharge (CD) or efference copy. In the old world monkey, such a CD circuit for saccades has been identified extending from superior colliculus through MD thalamus to frontal cortex, but there is little evidence that this circuit actually contributes to visual perception. We tested the influence of this CD circuit on visual perception by first training macaque monkeys to report their perceived eye direction, and then reversibly inactivating the CD as it passes through the thalamus. We found that the monkey's perception changed; during CD inactivation, there was a difference between where the monkey perceived its eyes to be directed and where they were actually directed. Perception and saccade were decoupled. We established that the perceived eye direction at the end of the saccade was not derived from proprioceptive input from eye muscles, and was not altered by contextual visual information. We conclude that the CD provides internal information contributing to the brain's creation of perceived visual stability. More specifically, the CD might provide the internal saccade vector used to unite separate retinal images into a stable visual scene. SIGNIFICANCE STATEMENT Visual stability is one of the most remarkable aspects of human vision. The eyes move rapidly several times per second, displacing the retinal image each time. The brain compensates for this disruption, keeping our visual perception stable. A major hypothesis explaining this stability invokes a signal within the brain, a corollary discharge, that informs visual regions of the brain when and where the eyes are about to move. Such a corollary discharge circuit for eye movements has been identified in macaque monkey. We now show that selectively inactivating this brain circuit alters the monkey's visual perception. We conclude that this corollary discharge provides a critical signal that can be used to unite jumping retinal images into a consistent visual scene. PMID:26740647

Dopamine receptor D4 internalization requires a beta-arrestin and a visual arrestin.

PubMed

Deming, Janise D; Shin, Jung-A; Lim, Kayleen; Lee, Eun-Jin; Van Craenenbroeck, Kathleen; Craft, Cheryl Mae

2015-10-01

The G-protein coupled receptor (GPCR) Dopamine Receptor D4 (DRD4) plays an essential role in cAMP regulation and gap junctional coupling in the photoreceptors, where DRD4 expression is under circadian control. Previous in vitro transfection studies of human DRD4 desensitization have reported that DRD4 is not internalized upon dopamine stimulation when beta-arrestin is co-transfected with DRD4. We hypothesized that the visual arrestins, ARR1 and ARR4, play a modulatory role in DRD4 desensitization in the photoreceptors. To test this hypothesis, immunohistochemistry analysis of mouse retinas was used to determine the cellular localization of beta-arrestins and DRD4 in photoreceptors. In vitro studies were performed in HEK293T cells transiently transfected with human DRD4 and arrestins. First, co-immunoprecipitation experiments were executed to test protein-protein interactions and to investigate the effect of dopamine stimulation. Second, immunohistochemistry analysis was implemented to study DRD4 internalization and translocation of ARR4. Immunohistochemistry studies of mouse retinas confirmed the expression of beta-arrestin 2, ARR1 and ARR4, as well as DRD4 in mouse cone photoreceptor inner segments. Co-immunoprecipitation experiments revealed a dopamine-dependent protein-protein interaction between human DRD4 and ARR4. In vitro internalization experiments showed that no detectable internalization of DRD4 was observed with any single arrestin co-transfected. However, a dopamine-dependent internalization of DRD4 was observed with three out of six sets of two arrestins co-transfected with DRD4. Each of these pairs of arrestins contained one visual arrestin and one beta-arrestin, and no internalization was observed with either two visual arrestins or two beta-arrestins. Additional time-course experiments revealed that in vitro, ARR4 translocates to co-localize with DRD4 at the plasma membrane in response to 30min of dopamine stimulation. The results have functional implications and we hypothesize that the desensitization and internalization of DRD4 in photoreceptors are synergistically mediated by both visual and beta-arrestins. These results are additionally unique because they demonstrate for the first time that at least one G-protein coupled receptor, DRD4, requires two arrestins for desensitization and internalization, and opens up the possibility that other G-protein coupled receptors may require more than one arrestin for desensitization and/or internalization. Copyright © 2015 Elsevier Inc. All rights reserved.

The Social Experiences of High School Students with Visual Impairments

ERIC Educational Resources Information Center

Jessup, Glenda; Bundy, Anita C.; Broom, Alex; Hancock, Nicola

2017-01-01

Introduction: This study explores the social experiences in high school of students with visual impairments. Methods: Experience sampling methodology was used to examine (a) how socially included students with visual impairments feel, (b) the internal qualities of their activities, and (c) the factors that influence a sense of inclusion. Twelve…

External and Internal Representations in the Acquisition and Use of Knowledge: Visualization Effects on Mental Model Construction

ERIC Educational Resources Information Center

Schnotz, Wolfgang; Kurschner, Christian

2008-01-01

This article investigates whether different formats of visualizing information result in different mental models constructed in learning from pictures, whether the different mental models lead to different patterns of performance in subsequently presented tasks, and how these visualization effects can be modified by further external…

Accommodating Scientific Illiteracy: Award-Winning Visualizations on the Covers of "Science"

ERIC Educational Resources Information Center

Gigante, Maria E.

2012-01-01

The International Science and Engineering Visualization Challenge, recently established by the National Science Foundation (NSF), is an alleged attempt at public outreach. The NSF encourages scientists to submit visualizations that would appeal to non-expert audiences by displaying their work in an annual "special feature" in "Science" magazine,…

Long-term effect of surface light scattering and glistenings of intraocular lenses on visual function.

PubMed

Hayashi, Ken; Hirata, Akira; Yoshida, Motoaki; Yoshimura, Koichi; Hayashi, Hideyuki

2012-08-01

To investigate the long-term effect of surface light scattering and glistenings of various intraocular lenses (IOLs) on visual function and optical aberrations after cataract surgery. Case-control study. Thirty-five eyes that underwent implantation of a hydrophobic acrylic, silicone, or polymethyl methacrylate (PMMA) IOL more than 10 years ago were recruited. The scattering light intensity of the surface and internal matrix of the optic was measured using Scheimpflug photography. Visual acuity (VA) was measured using VA charts, and contrast VA and that with glare (glare VA) were examined using a contrast sensitivity tester. Ocular higher-order aberrations (HOAs) were measured using a Hartmann-Shack aberrometer. Mean scattering light intensity of the surface and internal matrix of the optic was significantly higher in the acrylic group than in the silicone and PMMA groups (P < .0001). Mean uncorrected VA, photopic and mesopic contrast VA and glare VA, and HOAs did not differ significantly among groups, although mean corrected VA in the acrylic group was significantly better than that in the other groups (P = .0023). Scattering light intensity of the surface and internal matrix did not correlate with VA, contrast VA, or glare VA, and did not correlate with ocular and internal optic HOAs in the acrylic group. At more than 10 years postoperatively, visual function, including contrast sensitivity, and ocular HOAs were comparable among eyes that received acrylic, silicone, and PMMA IOLs. Surface scattering and glistenings with the acrylic IOLs were not significantly correlated with visual function and optical aberrations. Copyright © 2012 Elsevier Inc. All rights reserved.

Calibration of visually guided reaching is driven by error-corrective learning and internal dynamics.

PubMed

Cheng, Sen; Sabes, Philip N

2007-04-01

The sensorimotor calibration of visually guided reaching changes on a trial-to-trial basis in response to random shifts in the visual feedback of the hand. We show that a simple linear dynamical system is sufficient to model the dynamics of this adaptive process. In this model, an internal variable represents the current state of sensorimotor calibration. Changes in this state are driven by error feedback signals, which consist of the visually perceived reach error, the artificial shift in visual feedback, or both. Subjects correct for > or =20% of the error observed on each movement, despite being unaware of the visual shift. The state of adaptation is also driven by internal dynamics, consisting of a decay back to a baseline state and a "state noise" process. State noise includes any source of variability that directly affects the state of adaptation, such as variability in sensory feedback processing, the computations that drive learning, or the maintenance of the state. This noise is accumulated in the state across trials, creating temporal correlations in the sequence of reach errors. These correlations allow us to distinguish state noise from sensorimotor performance noise, which arises independently on each trial from random fluctuations in the sensorimotor pathway. We show that these two noise sources contribute comparably to the overall magnitude of movement variability. Finally, the dynamics of adaptation measured with random feedback shifts generalizes to the case of constant feedback shifts, allowing for a direct comparison of our results with more traditional blocked-exposure experiments.

Perceived visual informativeness (PVI): construct and scale development to assess visual information in printed materials.

PubMed

King, Andy J; Jensen, Jakob D; Davis, LaShara A; Carcioppolo, Nick

2014-01-01

There is a paucity of research on the visual images used in health communication messages and campaign materials. Even though many studies suggest further investigation of these visual messages and their features, few studies provide specific constructs or assessment tools for evaluating the characteristics of visual messages in health communication contexts. The authors conducted 2 studies to validate a measure of perceived visual informativeness (PVI), a message construct assessing visual messages presenting statistical or indexical information. In Study 1, a 7-item scale was created that demonstrated good internal reliability (α = .91), as well as convergent and divergent validity with related message constructs such as perceived message quality, perceived informativeness, and perceived attractiveness. PVI also converged with a preference for visual learning but was unrelated to a person's actual vision ability. In addition, PVI exhibited concurrent validity with a number of important constructs including perceived message effectiveness, decisional satisfaction, and three key public health theory behavior predictors: perceived benefits, perceived barriers, and self-efficacy. Study 2 provided more evidence that PVI is an internally reliable measure and demonstrates that PVI is a modifiable message feature that can be tested in future experimental work. PVI provides an initial step to assist in the evaluation and testing of visual messages in campaign and intervention materials promoting informed decision making and behavior change.

Operational Symbols: Can a Picture Be Worth a Thousand Words?

DTIC Science & Technology

1991-04-01

internal visualization, because forms are to visual communication what words are to verbal communication. From a psychological point of view, the process... Visual Communication . Washington, DC: National Education Association, 1960. Bohannan, Anthony G. "C31 In Support of the Land Commander," in Principles...captions guide what is learned from a picture or graphic. 40. John C. Ball and Francis C. Byrnes, ed., Research, Principles, and Practices in Visual

Visual skills involved in decision making by expert referees.

PubMed

Ghasemi, Abdollah; Momeni, Maryam; Jafarzadehpur, Ebrahim; Rezaee, Meysam; Taheri, Hamid

2011-02-01

Previous studies have compared visual skills of expert and novice athletes; referees' performance has not been addressed. Visual skills of two groups of expert referees, successful and unsuccessful in decision making, were compared. Using video clips of soccer matches to assess decision-making success of 41 national and international referees from 31 to 42 years of age, 10 top referees were selected as the Successful group and 10 as the Unsuccessful group. Visual tests included visual memory, visual reaction time, peripheral vision, recognition speed, saccadic eye movement, and facility of accommodation. The Successful group had better visual skills than the Unsuccessful group. Such visual skills enhance soccer referees' performance and may be recommended for young referees.

Studies of Visual Attention in Physics Problem Solving

ERIC Educational Resources Information Center

Madsen, Adrian M.

2013-01-01

The work described here represents an effort to understand and influence visual attention while solving physics problems containing a diagram. Our visual system is guided by two types of processes--top-down and bottom-up. The top-down processes are internal and determined by ones prior knowledge and goals. The bottom-up processes are external and…

Difference, Visual Narration, and "Point of View" in "My Name is Red"

ERIC Educational Resources Information Center

Cicekoglu, Feride

2003-01-01

This paper focuses on the difference between Eastern and Western ways of visual narration, taking as its frame of reference the novel "My Name is Red," by Turkish author Orhan Pamuk, winner of the 2003 International IMPAC Dublin Literary Award. This book is particularly important in terms of visual narration because it highlights the…

Collaboration in Visual Culture Learning Communities: Towards a Synergy of Individual and Collective Creative Practice

ERIC Educational Resources Information Center

Karpati, Andrea; Freedman, Kerry; Castro, Juan Carlos; Kallio-Tavin, Mira; Heijnen, Emiel

2017-01-01

A visual culture learning community (VCLC) is an adolescent or young adult group engaged in expression and creation outside of formal institutions and without adult supervision. In the framework of an international, comparative research project executed between 2010 and 2014, members of a variety of eight self-initiated visual culture groups…

Visualization Forms in the Cross-Cultural Collaborative Activities of Design and Development of a Digital Resource for Education

ERIC Educational Resources Information Center

Quan, Guolong; Gu, Xiaoqing

2018-01-01

Recent studies have demonstrated the integration of visualization technology to support collaboration and stimulate learning performance. The use of visualization tools during the collaborative activities of international students is a worthy topic for further exploration. Based on grounded and activity theories, this research uses observation and…

A giant dumbbell shaped vesico-prostatic urethral calculus: a case report and review of literature.

PubMed

Prabhuswamy, Vinod Kumar; Tiwari, Rahul; Krishnamoorthy, Ramakrishnan

2013-01-01

Calculi in the urethra are an uncommon entity. Giant calculi in prostatic urethra are extremely rare. The decision about treatment strategy of calculi depends upon the size, shape, and position of the calculus and the status of the urethra. If the stone is large and immovable, it may be extracted via the perineal or the suprapubic approach. In most of the previous reported cases, giant calculi were extracted via the transvesical approach and external urethrotomy. A 38-year-old male patient presented with complaints of lower urinary tract symptoms. Further investigations showed a giant urethral calculus secondary to stricture of bulbo-membranous part of the urethra. Surgical removal of calculus was done via transvesical approach. Two calculi were found and extracted. One was a huge dumbbell calculus and the other was a smaller round calculus. This case was reported because of the rare size and the dumbbell nature of the stone. Giant urethral calculi are better managed by open surgery.

A Giant Dumbbell Shaped Vesico-Prostatic Urethral Calculus: A Case Report and Review of Literature

PubMed Central

Prabhuswamy, Vinod Kumar; Tiwari, Rahul; Krishnamoorthy, Ramakrishnan

2013-01-01

Calculi in the urethra are an uncommon entity. Giant calculi in prostatic urethra are extremely rare. The decision about treatment strategy of calculi depends upon the size, shape, and position of the calculus and the status of the urethra. If the stone is large and immovable, it may be extracted via the perineal or the suprapubic approach. In most of the previous reported cases, giant calculi were extracted via the transvesical approach and external urethrotomy. A 38-year-old male patient presented with complaints of lower urinary tract symptoms. Further investigations showed a giant urethral calculus secondary to stricture of bulbo-membranous part of the urethra. Surgical removal of calculus was done via transvesical approach. Two calculi were found and extracted. One was a huge dumbbell calculus and the other was a smaller round calculus. This case was reported because of the rare size and the dumbbell nature of the stone. Giant urethral calculi are better managed by open surgery. PMID:23762742

Expert identification of visual primitives used by CNNs during mammogram classification

NASA Astrophysics Data System (ADS)

Wu, Jimmy; Peck, Diondra; Hsieh, Scott; Dialani, Vandana; Lehman, Constance D.; Zhou, Bolei; Syrgkanis, Vasilis; Mackey, Lester; Patterson, Genevieve

2018-02-01

This work interprets the internal representations of deep neural networks trained for classification of diseased tissue in 2D mammograms. We propose an expert-in-the-loop inter- pretation method to label the behavior of internal units in convolutional neural networks (CNNs). Expert radiologists identify that the visual patterns detected by the units are correlated with meaningful medical phenomena such as mass tissue and calcificated vessels. We demonstrate that several trained CNN models are able to produce explanatory descriptions to support the final classification decisions. We view this as an important first step toward interpreting the internal representations of medical classification CNNs and explaining their predictions.

Stereoscopic augmented reality for laparoscopic surgery.

PubMed

Kang, Xin; Azizian, Mahdi; Wilson, Emmanuel; Wu, Kyle; Martin, Aaron D; Kane, Timothy D; Peters, Craig A; Cleary, Kevin; Shekhar, Raj

2014-07-01

Conventional laparoscopes provide a flat representation of the three-dimensional (3D) operating field and are incapable of visualizing internal structures located beneath visible organ surfaces. Computed tomography (CT) and magnetic resonance (MR) images are difficult to fuse in real time with laparoscopic views due to the deformable nature of soft-tissue organs. Utilizing emerging camera technology, we have developed a real-time stereoscopic augmented-reality (AR) system for laparoscopic surgery by merging live laparoscopic ultrasound (LUS) with stereoscopic video. The system creates two new visual cues: (1) perception of true depth with improved understanding of 3D spatial relationships among anatomical structures, and (2) visualization of critical internal structures along with a more comprehensive visualization of the operating field. The stereoscopic AR system has been designed for near-term clinical translation with seamless integration into the existing surgical workflow. It is composed of a stereoscopic vision system, a LUS system, and an optical tracker. Specialized software processes streams of imaging data from the tracked devices and registers those in real time. The resulting two ultrasound-augmented video streams (one for the left and one for the right eye) give a live stereoscopic AR view of the operating field. The team conducted a series of stereoscopic AR interrogations of the liver, gallbladder, biliary tree, and kidneys in two swine. The preclinical studies demonstrated the feasibility of the stereoscopic AR system during in vivo procedures. Major internal structures could be easily identified. The system exhibited unobservable latency with acceptable image-to-video registration accuracy. We presented the first in vivo use of a complete system with stereoscopic AR visualization capability. This new capability introduces new visual cues and enhances visualization of the surgical anatomy. The system shows promise to improve the precision and expand the capacity of minimally invasive laparoscopic surgeries.

Real-time phase-contrast x-ray imaging: a new technique for the study of animal form and function

PubMed Central

Socha, John J; Westneat, Mark W; Harrison, Jon F; Waters, James S; Lee, Wah-Keat

2007-01-01

Background Despite advances in imaging techniques, real-time visualization of the structure and dynamics of tissues and organs inside small living animals has remained elusive. Recently, we have been using synchrotron x-rays to visualize the internal anatomy of millimeter-sized opaque, living animals. This technique takes advantage of partially-coherent x-rays and diffraction to enable clear visualization of internal soft tissue not viewable via conventional absorption radiography. However, because higher quality images require greater x-ray fluxes, there exists an inherent tradeoff between image quality and tissue damage. Results We evaluated the tradeoff between image quality and harm to the animal by determining the impact of targeted synchrotron x-rays on insect physiology, behavior and survival. Using 25 keV x-rays at a flux density of 80 μW/mm-2, high quality video-rate images can be obtained without major detrimental effects on the insects for multiple minutes, a duration sufficient for many physiological studies. At this setting, insects do not heat up. Additionally, we demonstrate the range of uses of synchrotron phase-contrast imaging by showing high-resolution images of internal anatomy and observations of labeled food movement during ingestion and digestion. Conclusion Synchrotron x-ray phase contrast imaging has the potential to revolutionize the study of physiology and internal biomechanics in small animals. This is the only generally applicable technique that has the necessary spatial and temporal resolutions, penetrating power, and sensitivity to soft tissue that is required to visualize the internal physiology of living animals on the scale from millimeters to microns. PMID:17331247

Visually representing reality: aesthetics and accessibility aspects

NASA Astrophysics Data System (ADS)

van Nes, Floris L.

2009-02-01

This paper gives an overview of the visual representation of reality with three imaging technologies: painting, photography and electronic imaging. The contribution of the important image aspects, called dimensions hereafter, such as color, fine detail and total image size, to the degree of reality and aesthetic value of the rendered image are described for each of these technologies. Whereas quite a few of these dimensions - or approximations, or even only suggestions thereof - were already present in prehistoric paintings, apparent motion and true stereoscopic vision only recently were added - unfortunately also introducing accessibility and image safety issues. Efforts are made to reduce the incidence of undesirable biomedical effects such as photosensitive seizures (PSS), visually induced motion sickness (VIMS), and visual fatigue from stereoscopic images (VFSI) by international standardization of the image parameters to be avoided by image providers and display manufacturers. The history of this type of standardization, from an International Workshop Agreement to a strategy for accomplishing effective international standardization by ISO, is treated at some length. One of the difficulties to be mastered in this process is the reconciliation of the, sometimes opposing, interests of vulnerable persons, thrill-seeking viewers, creative video designers and the game industry.

Visual Confirmation of Voice Takeoff Clearance (VICON) Alternative Study

DOT National Transportation Integrated Search

1980-05-01

This report presents the results of a program undertaken to study potential alternatives to the VICON (Visual Confirmation of Voice Takeoff Clearance) System which has undergone operational field tests at Bradley International Airport, Windsor Locks,...

Isolating Visual and Proprioceptive Components of Motor Sequence Learning in ASD.

PubMed

Sharer, Elizabeth A; Mostofsky, Stewart H; Pascual-Leone, Alvaro; Oberman, Lindsay M

2016-05-01

In addition to defining impairments in social communication skills, individuals with autism spectrum disorder (ASD) also show impairments in more basic sensory and motor skills. Development of new skills involves integrating information from multiple sensory modalities. This input is then used to form internal models of action that can be accessed when both performing skilled movements, as well as understanding those actions performed by others. Learning skilled gestures is particularly reliant on integration of visual and proprioceptive input. We used a modified serial reaction time task (SRTT) to decompose proprioceptive and visual components and examine whether patterns of implicit motor skill learning differ in ASD participants as compared with healthy controls. While both groups learned the implicit motor sequence during training, healthy controls showed robust generalization whereas ASD participants demonstrated little generalization when visual input was constant. In contrast, no group differences in generalization were observed when proprioceptive input was constant, with both groups showing limited degrees of generalization. The findings suggest, when learning a motor sequence, individuals with ASD tend to rely less on visual feedback than do healthy controls. Visuomotor representations are considered to underlie imitative learning and action understanding and are thereby crucial to social skill and cognitive development. Thus, anomalous patterns of implicit motor learning, with a tendency to discount visual feedback, may be an important contributor in core social communication deficits that characterize ASD. Autism Res 2016, 9: 563-569. © 2015 International Society for Autism Research, Wiley Periodicals, Inc. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.

Processing of visual gravitational motion in the peri-sylvian cortex: Evidence from brain-damaged patients.

PubMed

Maffei, Vincenzo; Mazzarella, Elisabetta; Piras, Fabrizio; Spalletta, Gianfranco; Caltagirone, Carlo; Lacquaniti, Francesco; Daprati, Elena

2016-05-01

Rich behavioral evidence indicates that the brain estimates the visual direction and acceleration of gravity quite accurately, and the underlying mechanisms have begun to be unraveled. While the neuroanatomical substrates of gravity direction processing have been studied extensively in brain-damaged patients, to our knowledge no such study exists for the processing of visual gravitational motion. Here we asked 31 stroke patients to intercept a virtual ball moving along the vertical under either natural gravity or artificial reversed gravity. Twenty-seven of them also aligned a luminous bar to the vertical direction (subjective visual vertical, SVV). Using voxel-based lesion-symptom mapping as well as lesion subtraction analysis, we found that lesions mainly centered on the posterior insula are associated with greater deviations of SVV, consistent with several previous studies. Instead, lesions mainly centered on the parietal operculum decrease the ability to discriminate natural from unnatural gravitational acceleration with a timed motor response in the interception task. Both the posterior insula and the parietal operculum belong to the vestibular cortex, and presumably receive multisensory information about the gravity vector. We speculate that an internal model estimating the effects of gravity on visual objects is constructed by transforming the vestibular estimates of mechanical gravity, which are computed in the brainstem and cerebellum, into internalized estimates of virtual gravity, which are stored in the cortical vestibular network. The present lesion data suggest a specific role for the parietal operculum in detecting the mismatch between predictive signals from the internal model and the online visual signals. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Visual System's Intrinsic Bias and Knowledge of Size Mediate Perceived Size and Location in the Dark

ERIC Educational Resources Information Center

Zhou, Liu; He, Zijiang J.; Ooi, Teng Leng

2013-01-01

Dimly lit targets in the dark are perceived as located about an implicit slanted surface that delineates the visual system's intrinsic bias (Ooi, Wu, & He, 2001). If the intrinsic bias reflects the internal model of visual space--as proposed here--its influence should extend beyond target localization. Our first 2 experiments demonstrated that…

How a Visual Language of Abstract Shapes Facilitates Cultural and International Border Crossings

ERIC Educational Resources Information Center

Conroy, Arthur Thomas, III

2016-01-01

This article describes a visual language comprised of abstract shapes that has been shown to be effective in communicating prior knowledge between and within members of a small team or group. The visual language includes a set of geometric shapes and rules that guide the construction of the abstract diagrams that are the external representation of…

FMRI investigation of cross-modal interactions in beat perception: Audition primes vision, but not vice versa

PubMed Central

Grahn, Jessica A.; Henry, Molly J.; McAuley, J. Devin

2011-01-01

How we measure time and integrate temporal cues from different sensory modalities are fundamental questions in neuroscience. Sensitivity to a “beat” (such as that routinely perceived in music) differs substantially between auditory and visual modalities. Here we examined beat sensitivity in each modality, and examined cross-modal influences, using functional magnetic resonance imaging (fMRI) to characterize brain activity during perception of auditory and visual rhythms. In separate fMRI sessions, participants listened to auditory sequences or watched visual sequences. The order of auditory and visual sequence presentation was counterbalanced so that cross-modal order effects could be investigated. Participants judged whether sequences were speeding up or slowing down, and the pattern of tempo judgments was used to derive a measure of sensitivity to an implied beat. As expected, participants were less sensitive to an implied beat in visual sequences than in auditory sequences. However, visual sequences produced a stronger sense of beat when preceded by auditory sequences with identical temporal structure. Moreover, increases in brain activity were observed in the bilateral putamen for visual sequences preceded by auditory sequences when compared to visual sequences without prior auditory exposure. No such order-dependent differences (behavioral or neural) were found for the auditory sequences. The results provide further evidence for the role of the basal ganglia in internal generation of the beat and suggest that an internal auditory rhythm representation may be activated during visual rhythm perception. PMID:20858544

Visual Confirmation (VICON) of Takeoff Clearance Signal System Impact Study

DOT National Transportation Integrated Search

1980-11-01

A study was performed to evaluate the impact on airport capacity and voice communications of the Visual Confirmation of Takeoff Clearance (VICON) Signal System. Befoe-and-after test data collection and analysis were conducted at Bradley International...

Micro-calibration of space and motion by photoreceptors synchronized in parallel with cortical oscillations: A unified theory of visual perception.

PubMed

Jerath, Ravinder; Cearley, Shannon M; Barnes, Vernon A; Jensen, Mike

2018-01-01

A fundamental function of the visual system is detecting motion, yet visual perception is poorly understood. Current research has determined that the retina and ganglion cells elicit responses for motion detection; however, the underlying mechanism for this is incompletely understood. Previously we proposed that retinogeniculo-cortical oscillations and photoreceptors work in parallel to process vision. Here we propose that motion could also be processed within the retina, and not in the brain as current theory suggests. In this paper, we discuss: 1) internal neural space formation; 2) primary, secondary, and tertiary roles of vision; 3) gamma as the secondary role; and 4) synchronization and coherence. Movement within the external field is instantly detected by primary processing within the space formed by the retina, providing a unified view of the world from an internal point of view. Our new theory begins to answer questions about: 1) perception of space, erect images, and motion, 2) purpose of lateral inhibition, 3) speed of visual perception, and 4) how peripheral color vision occurs without a large population of cones located peripherally in the retina. We explain that strong oscillatory activity influences on brain activity and is necessary for: 1) visual processing, and 2) formation of the internal visuospatial area necessary for visual consciousness, which could allow rods to receive precise visual and visuospatial information, while retinal waves could link the lateral geniculate body with the cortex to form a neural space formed by membrane potential-based oscillations and photoreceptors. We propose that vision is tripartite, with three components that allow a person to make sense of the world, terming them "primary, secondary, and tertiary roles" of vision. Finally, we propose that Gamma waves that are higher in strength and volume allow communication among the retina, thalamus, and various areas of the cortex, and synchronization brings cortical faculties to the retina, while the thalamus is the link that couples the retina to the rest of the brain through activity by gamma oscillations. This novel theory lays groundwork for further research by providing a theoretical understanding that expands upon the functions of the retina, photoreceptors, and retinal plexus to include parallel processing needed to form the internal visual space that we perceive as the external world. Copyright © 2017 Elsevier Ltd. All rights reserved.

Surgical tips and tricks during urethroplasty for bulbar urethral strictures focusing on accurate localisation of the stricture: results from a tertiary centre.

PubMed

Kuo, Tricia L C; Venugopal, Suresh; Inman, Richard D; Chapple, Christopher R

2015-04-01

There are several techniques for characterising and localising an anterior urethral stricture, such as preoperative retrograde urethrography, ultrasonography, and endoscopy. However, these techniques have some limitations. The final determinant is intraoperative assessment, as this yields the most information and defines what surgical procedure is undertaken. We present our intraoperative approach for localising and operating on a urethral stricture, with assessment of outcomes. A retrospective review of urethral strictures operated was carried out. All patients had a bulbar or bulbomembranous urethroplasty. All patients were referred to a tertiary centre and operated on by two urethral reconstructive surgeons. Intraoperative identification of the stricture was performed by cystoscopy. The location of the stricture is demonstrated externally on the urethra by external transillumination of the urethra and comparison with the endoscopic picture. This is combined with accurate placement of a suture through the urethra, at the distal extremity of the stricture, verified precisely by endoscopy. Clinical data were collected in a dedicated database. Intraoperative details and postoperative follow-up data for each patient were recorded and analysed. A descriptive data analysis was performed. A representative group of 35 male patients who had surgery for bulbar stricture was randomly selected from January 2010 to December 2013. Mean follow-up was 13.8 mo (range 2-43 mo). Mean age was 46.5 yr (range 17-70 yr). Three patients had undergone previous urethroplasty and 26 patients had previous urethrotomy or dilatation. All patients had preoperative retrograde urethrography and most (85.7%) had endoscopic assessment. The majority of patients (48.6%) had a stricture length of >2-7 cm and 45.7% of patients required a buccal mucosa graft. There were no intraoperative complications. Postoperatively, two patients had a urinary tract infection. All patients were assessed postoperatively via flexible cystoscopy. Only one patient required subsequent optical urethrotomy for recurrence. Our intraoperative strategy for anterior urethral stricture assessment provides a clear stepwise approach, regardless of the type of urethroplasty eventually chosen (anastomotic disconnected or Heineke-Mikulicz) or augmentation (dorsal, ventral, or augmented roof strip). It is useful in all cases by allowing precise localisation of the incision in the urethra, whether the stricture is simple or complex. We studied the treatment of bulbar urethral strictures with different types of urethroplasty, using a specific technique to identify and characterise the length of the stricture. This technique is effective, precise, and applicable to all patients undergoing urethroplasty for bulbar urethral stricture. Copyright © 2014 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Bilateral Symmetry of Visual Function Loss in Cone-Rod Dystrophies.

PubMed

Galli-Resta, Lucia; Falsini, Benedetto; Rossi, Giuseppe; Piccardi, Marco; Ziccardi, Lucia; Fadda, Antonello; Minnella, Angelo; Marangoni, Dario; Placidi, Giorgio; Campagna, Francesca; Abed, Edoardo; Bertelli, Matteo; Zuntini, Monia; Resta, Giovanni

2016-07-01

To investigate bilateral symmetry of visual impairment in cone-rod dystrophy (CRD) patients and understand the feasibility of clinical trial designs treating one eye and using the untreated eye as an internal control. This was a retrospective study of visual function loss measures in 436 CRD patients followed at the Ophthalmology Department of the Catholic University in Rome. Clinical measures considered were best-corrected visual acuity, focal macular cone electroretinogram (fERG), and Ganzfeld cone-mediated and rod-mediated electroretinograms. Interocular agreement in each of these clinical indexes was assessed by t- and Wilcoxon tests for paired samples, structural (Deming) regression analysis, and intraclass correlation. Baseline and follow-up measures were analyzed. A separate analysis was performed on the subset of 61 CRD patients carrying likely disease-causing mutations in the ABCA4 gene. Statistical tests show a very high degree of bilateral symmetry in the extent and progression of visual impairment in the fellow eyes of CRD patients. These data contribute to a better understanding of CRDs and support the feasibility of clinical trial designs involving unilateral eye treatment with the use of fellow eye as internal control.

Performance improvements from imagery: evidence that internal visual imagery is superior to external visual imagery for slalom performance

PubMed Central

Callow, Nichola; Roberts, Ross; Hardy, Lew; Jiang, Dan; Edwards, Martin Gareth

2013-01-01

We report three experiments investigating the hypothesis that use of internal visual imagery (IVI) would be superior to external visual imagery (EVI) for the performance of different slalom-based motor tasks. In Experiment 1, three groups of participants (IVI, EVI, and a control group) performed a driving-simulation slalom task. The IVI group achieved significantly quicker lap times than EVI and the control group. In Experiment 2, participants performed a downhill running slalom task under both IVI and EVI conditions. Performance was again quickest in the IVI compared to EVI condition, with no differences in accuracy. Experiment 3 used the same group design as Experiment 1, but with participants performing a downhill ski-slalom task. Results revealed the IVI group to be significantly more accurate than the control group, with no significant differences in time taken to complete the task. These results support the beneficial effects of IVI for slalom-based tasks, and significantly advances our knowledge related to the differential effects of visual imagery perspectives on motor performance. PMID:24155710

Prototype Stop Bar System Evaluation at John F. Kennedy International Airport

DTIC Science & Technology

1992-09-01

2 Red Stop Bar Visual Presentation 4 3 Green Stop Bar Visual Presentation 5 4 Photographs of Red and Green Inset Stop Bar Lights 6 5 Photographs of...to green. This provides pilots with a visual confirmation of the controller’s verbal clearance and is intended to prevent runway incursions. The Port...34 colocated with the red lights. The visual presentation of an individual stop bar appears as either five red lights (see figure 2), or five green

Visual Times of Maxima for Short Period Pulsating Stars II

NASA Astrophysics Data System (ADS)

Samolyk, G.

2017-12-01

This compilation contains 631 times of maxima of 8 short period pulsating stars (primarily RR Lyrae). These were reduced from a portion of the visual observations made from 1966 to 2014 that are included in the AAVSO International Database.

Art, Science & Visual Literacy: Selected Readings from the Annual Conference of the International Visual Literacy Association (24th, Pittsburgh, Pennsylvania, September 30-October 4, 1992).

ERIC Educational Resources Information Center

Braden, Roberts A., Ed.; And Others

Following an introductory paper on Pittsburgh and the arts, 57 conference papers are presented under the following four major categories: (1) "Imagery, Science and the Arts," including discovery in art and science, technology and art, visual design of newspapers, multimedia science education, science learning and interactive videodisc technology,…

The global lambda visualization facility: An international ultra-high-definition wide-area visualization collaboratory

USGS Publications Warehouse

Leigh, J.; Renambot, L.; Johnson, Aaron H.; Jeong, B.; Jagodic, R.; Schwarz, N.; Svistula, D.; Singh, R.; Aguilera, J.; Wang, X.; Vishwanath, V.; Lopez, B.; Sandin, D.; Peterka, T.; Girado, J.; Kooima, R.; Ge, J.; Long, L.; Verlo, A.; DeFanti, T.A.; Brown, M.; Cox, D.; Patterson, R.; Dorn, P.; Wefel, P.; Levy, S.; Talandis, J.; Reitzer, J.; Prudhomme, T.; Coffin, T.; Davis, B.; Wielinga, P.; Stolk, B.; Bum, Koo G.; Kim, J.; Han, S.; Corrie, B.; Zimmerman, T.; Boulanger, P.; Garcia, M.

2006-01-01

The research outlined in this paper marks an initial global cooperative effort between visualization and collaboration researchers to build a persistent virtual visualization facility linked by ultra-high-speed optical networks. The goal is to enable the comprehensive and synergistic research and development of the necessary hardware, software and interaction techniques to realize the next generation of end-user tools for scientists to collaborate on the global Lambda Grid. This paper outlines some of the visualization research projects that were demonstrated at the iGrid 2005 workshop in San Diego, California.

Internal limiting membrane peeling and gas tamponade for myopic foveoschisis: a systematic review and meta-analysis.

PubMed

Meng, Bo; Zhao, Lu; Yin, Yi; Li, Hongyang; Wang, Xiaolei; Yang, Xiufen; You, Ran; Wang, Jialin; Zhang, Youjing; Wang, Hui; Du, Ran; Wang, Ningli; Zhan, Siyan; Wang, Yanling

2017-09-08

Myopic foveoschisis (MF) is among the leading causes of visual loss in high myopia. However, it remains controversial whether internal limiting membrane (ILM) peeling or gas tamponade is necessary treatment option for MF. PubMed, EMBASE, CBM, CNKI, WANFANG DATA and VIP databases were systematically reviewed. Outcome indicators were myopic foveoschisis resolution rate, visual acuity improvement and postoperative complications. Nine studies that included 239 eyes were selected. The proportion of resolution of foveoschisis was higher in ILM peeling group than non-ILM peeling group (OR = 2.15, 95% CI: 1.06-4.35; P = 0.03). The proportion of postoperative complications was higher in Tamponade group than non-Tamponade group (OR = 10.81, 95% CI: 1.26-93.02; P = 0.03). However, the proportion of visual acuity improvement (OR = 1.63, 95% CI: 0.56-4.80; P = 0.37) between ILM peeling group and non-ILM peeling group and the proportion of resolution of foveoschisis (OR = 1.80, 95% CI: 0.76-4.28; P = 0.18) between Tamponade group and non-Tamponade group were similar. Vitrectomy with internal limiting membrane peeling could contribute to better resolution of myopic foveoschisis than non-peeling, however it does not significantly influence the proportion of visual acuity improvement and postoperative complications. Vitrectomy with gas tamponade is associated with more complications than non-tamponade and does not significantly influence the proportion of visual acuity improvement and resolution of myopic foveoschisis.

Toward International Comparability of Survey Statistics on Visual Impairment: The DISTAB Project

ERIC Educational Resources Information Center

Hendershot, Gerry E.; Crews, John E.

2006-01-01

Using data from recent national disability surveys in Australia, Canada, France, the Netherlands, South Africa, and the United States, an international team of researchers coded indicators of several types of disability using the International Classification of Functioning, Disability, and Health. This article discusses the Disability Tabulations…

Vision/Visual Perception: An Annotated Bibliography.

ERIC Educational Resources Information Center

Weintraub, Sam, Comp.; Cowan, Robert J., Comp.

An update and modification of "Vision-Visual Discrimination" published in 1973, this annotated bibliography contains entries from the annual summaries of research in reading published by the International Reading Association (IRA) since then. The first large section, "Vision," is divided into two subgroups: (1) "Visually…

An insect-inspired model for visual binding I: learning objects and their characteristics.

PubMed

Northcutt, Brandon D; Dyhr, Jonathan P; Higgins, Charles M

2017-04-01

Visual binding is the process of associating the responses of visual interneurons in different visual submodalities all of which are responding to the same object in the visual field. Recently identified neuropils in the insect brain termed optic glomeruli reside just downstream of the optic lobes and have an internal organization that could support visual binding. Working from anatomical similarities between optic and olfactory glomeruli, we have developed a model of visual binding based on common temporal fluctuations among signals of independent visual submodalities. Here we describe and demonstrate a neural network model capable both of refining selectivity of visual information in a given visual submodality, and of associating visual signals produced by different objects in the visual field by developing inhibitory neural synaptic weights representing the visual scene. We also show that this model is consistent with initial physiological data from optic glomeruli. Further, we discuss how this neural network model may be implemented in optic glomeruli at a neuronal level.

Negative BOLD in sensory cortices during verbal memory: a component in generating internal representations?

PubMed

Azulay, Haim; Striem, Ella; Amedi, Amir

2009-05-01

People tend to close their eyes when trying to retrieve an event or a visual image from memory. However the brain mechanisms behind this phenomenon remain poorly understood. Recently, we showed that during visual mental imagery, auditory areas show a much more robust deactivation than during visual perception. Here we ask whether this is a special case of a more general phenomenon involving retrieval of intrinsic, internally stored information, which would result in crossmodal deactivations in other sensory cortices which are irrelevant to the task at hand. To test this hypothesis, a group of 9 sighted individuals were scanned while performing a memory retrieval task for highly abstract words (i.e., with low imaginability scores). We also scanned a group of 10 congenitally blind, which by definition do not have any visual imagery per se. In sighted subjects, both auditory and visual areas were robustly deactivated during memory retrieval, whereas in the blind the auditory cortex was deactivated while visual areas, shown previously to be relevant for this task, presented a positive BOLD signal. These results suggest that deactivation may be most prominent in task-irrelevant sensory cortices whenever there is a need for retrieval or manipulation of internally stored representations. Thus, there is a task-dependent balance of activation and deactivation that might allow maximization of resources and filtering out of non relevant information to enable allocation of attention to the required task. Furthermore, these results suggest that the balance between positive and negative BOLD might be crucial to our understanding of a large variety of intrinsic and extrinsic tasks including high-level cognitive functions, sensory processing and multisensory integration.

INDUCTION OF MACULAR DETACHMENT FOR THE TREATMENT OF PERSISTENT OR RECURRENT IDIOPATHIC MACULAR HOLES.

PubMed

Szigiato, Andrei-Alexandru; Gilani, Fatimah; Walsh, Mark K; Mandelcorn, Efrem D; Muni, Rajeev H

2016-09-01

To analyze the efficacy of induced macular detachment for the treatment of persistent or recurrent idiopathic macular holes after treatment with one or more standard pars plana vitrectomies (PPVs) with internal limiting membrane peeling. This study is a retrospective consecutive case series of 10 patients who underwent a PPV with subretinal balanced salt solution injection from 2011 to 2014 to treat persistent or recurrent idiopathic macular holes. All patients had previously undergone PPV with internal limiting membrane peeling. Visual acuity, ocular examination findings, and optical coherence tomographic images were reviewed preoperatively and postoperatively to assess the anatomical and visual outcomes of this procedure. Nine of the 10 patients who underwent the procedure had closure of their macular holes postoperatively (90%) and remained closed 6 months postoperatively. Most patients reported a subjective visual improvement. A mean objective visual improvement of 16 letters (Early Treatment Diabetic Retinopathy Study, 0.324 logMAR) was seen between preoperative and 6-month postoperative assessments of all patients (pre = 1.490, post = 1.166; P = 0.022). Subgroup analysis of patients with successful closure revealed 20 letters of improvement (0.398 logMAR) in visual acuity (pre = 1.491, post = 1.093; P = 0.004). There were no intraoperative or postoperative complications. In eyes with persistent or recurrent idiopathic macular holes after standard PPV with internal limiting membrane peeling, repeat PPV with subretinal balanced salt solution injection to create a macular detachment may be a viable surgical treatment option. Our results show improved anatomical and visual outcomes postoperatively that compare favorably to other case series describing various surgical treatments for these challenging cases.

Canonical Visual Size for Real-World Objects

PubMed Central

Konkle, Talia; Oliva, Aude

2012-01-01

Real-world objects can be viewed at a range of distances and thus can be experienced at a range of visual angles within the visual field. Given the large amount of visual size variation possible when observing objects, we examined how internal object representations represent visual size information. In a series of experiments which required observers to access existing object knowledge, we observed that real-world objects have a consistent visual size at which they are drawn, imagined, and preferentially viewed. Importantly, this visual size is proportional to the logarithm of the assumed size of the object in the world, and is best characterized not as a fixed visual angle, but by the ratio of the object and the frame of space around it. Akin to the previous literature on canonical perspective, we term this consistent visual size information the canonical visual size. PMID:20822298

A Bayesian model for visual space perception

NASA Technical Reports Server (NTRS)

Curry, R. E.

1972-01-01

A model for visual space perception is proposed that contains desirable features in the theories of Gibson and Brunswik. This model is a Bayesian processor of proximal stimuli which contains three important elements: an internal model of the Markov process describing the knowledge of the distal world, the a priori distribution of the state of the Markov process, and an internal model relating state to proximal stimuli. The universality of the model is discussed and it is compared with signal detection theory models. Experimental results of Kinchla are used as a special case.

Background: Preflight Screening, In-flight Capabilities, and Postflight Testing

NASA Technical Reports Server (NTRS)

Gibson, Charles Robert; Duncan, James

2009-01-01

Recommendations for minimal in-flight capabilities: Retinal Imaging - provide in-flight capability for the visual monitoring of ocular health (specifically, imaging of the retina and optic nerve head) with the capability of downlinking video/still images. Tonometry - provide more accurate and reliable in-flight capability for measuring intraocular pressure. Ultrasound - explore capabilities of current on-board system for monitoring ocular health. We currently have limited in-flight capabilities on board the International Space Station for performing an internal ocular health assessment. Visual Acuity, Direct Ophthalmoscope, Ultrasound, Tonometry(Tonopen):

The mere exposure effect for visual image.

PubMed

Inoue, Kazuya; Yagi, Yoshihiko; Sato, Nobuya

2018-02-01

Mere exposure effect refers to a phenomenon in which repeated stimuli are evaluated more positively than novel stimuli. We investigated whether this effect occurs for internally generated visual representations (i.e., visual images). In an exposure phase, a 5 × 5 dot array was presented, and a pair of dots corresponding to the neighboring vertices of an invisible polygon was sequentially flashed (in red), creating an invisible polygon. In Experiments 1, 2, and 4, participants visualized and memorized the shapes of invisible polygons based on different sequences of flashed dots, whereas in Experiment 3, participants only memorized positions of these dots. In a subsequent rating phase, participants visualized the shape of the invisible polygon from allocations of numerical characters on its vertices, and then rated their preference for invisible polygons (Experiments 1, 2, and 3). In contrast, in Experiment 4, participants rated the preference for visible polygons. Results showed that the mere exposure effect appeared only when participants visualized the shape of invisible polygons in both the exposure and rating phases (Experiments 1 and 2), suggesting that the mere exposure effect occurred for internalized visual images. This implies that the sensory inputs from repeated stimuli play a minor role in the mere exposure effect. Absence of the mere exposure effect in Experiment 4 suggests that the consistency of processing between exposure and rating phases plays an important role in the mere exposure effect.

Coordinating Council. Second Meeting: International Acquisitions

NASA Technical Reports Server (NTRS)

1990-01-01

The theme of this NASA Scientific and Technical Information Program Coordinating Council was International Acquisitions. Included are both visuals for presentations and reports on discussions related to the topics. Presentations were made on the following topics: Coordination council organization international plan, STI global network, International aerospace climate, Foreign exchange program, Foreign activities RMS & AIAA, NASA translation program, A.F. machine translation system, and CIRC cooperation.

More visual mind wandering occurrence during visual task performance: Modality of the concurrent task affects how the mind wanders.

PubMed

Choi, HeeSun; Geden, Michael; Feng, Jing

2017-01-01

Mind wandering has been considered as a mental process that is either independent from the concurrent task or regulated like a secondary task. These accounts predict that the form of mind wandering (i.e., images or words) should be either unaffected by or different from the modality form (i.e., visual or auditory) of the concurrent task. Findings from this study challenge these accounts. We measured the rate and the form of mind wandering in three task conditions: fixation, visual 2-back, and auditory 2-back. Contrary to the general expectation, we found that mind wandering was more likely in the same form as the task. This result can be interpreted in light of recent findings on overlapping brain activations during internally- and externally-oriented processes. Our result highlights the importance to consider the unique interplay between the internal and external mental processes and to measure mind wandering as a multifaceted rather than a unitary construct.

CEOS visualization environment (COVE) tool for intercalibration of satellite instruments

USGS Publications Warehouse

Kessler, P.D.; Killough, B.D.; Gowda, S.; Williams, B.R.; Chander, G.; Qu, Min

2013-01-01

Increasingly, data from multiple instruments are used to gain a more complete understanding of land surface processes at a variety of scales. Intercalibration, comparison, and coordination of satellite instrument coverage areas is a critical effort of international and domestic space agencies and organizations. The Committee on Earth Observation Satellites Visualization Environment (COVE) is a suite of browser-based applications that leverage Google Earth to display past, present, and future satellite instrument coverage areas and coincident calibration opportunities. This forecasting and ground coverage analysis and visualization capability greatly benefits the remote sensing calibration community in preparation for multisatellite ground calibration campaigns or individual satellite calibration studies. COVE has been developed for use by a broad international community to improve the efficiency and efficacy of such calibration planning efforts, whether those efforts require past, present, or future predictions. This paper provides a brief overview of the COVE tool, its validation, accuracies, and limitations with emphasis on the applicability of this visualization tool for supporting ground field campaigns and intercalibration of satellite instruments.

CEOS Visualization Environment (COVE) Tool for Intercalibration of Satellite Instruments

NASA Technical Reports Server (NTRS)

Kessler, Paul D.; Killough, Brian D.; Gowda, Sanjay; Williams, Brian R.; Chander, Gyanesh; Qu, Min

2013-01-01

Increasingly, data from multiple instruments are used to gain a more complete understanding of land surface processes at a variety of scales. Intercalibration, comparison, and coordination of satellite instrument coverage areas is a critical effort of space agencies and of international and domestic organizations. The Committee on Earth Observation Satellites Visualization Environment (COVE) is a suite of browser-based applications that leverage Google Earth to display past, present, and future satellite instrument coverage areas and coincident calibration opportunities. This forecasting and ground coverage analysis and visualization capability greatly benefits the remote sensing calibration community in preparation for multisatellite ground calibration campaigns or individual satellite calibration studies. COVE has been developed for use by a broad international community to improve the efficiency and efficacy of such calibration efforts. This paper provides a brief overview of the COVE tool, its validation, accuracies and limitations with emphasis on the applicability of this visualization tool for supporting ground field campaigns and intercalibration of satellite instruments.

More visual mind wandering occurrence during visual task performance: Modality of the concurrent task affects how the mind wanders

PubMed Central

Choi, HeeSun; Geden, Michael

2017-01-01

Mind wandering has been considered as a mental process that is either independent from the concurrent task or regulated like a secondary task. These accounts predict that the form of mind wandering (i.e., images or words) should be either unaffected by or different from the modality form (i.e., visual or auditory) of the concurrent task. Findings from this study challenge these accounts. We measured the rate and the form of mind wandering in three task conditions: fixation, visual 2-back, and auditory 2-back. Contrary to the general expectation, we found that mind wandering was more likely in the same form as the task. This result can be interpreted in light of recent findings on overlapping brain activations during internally- and externally-oriented processes. Our result highlights the importance to consider the unique interplay between the internal and external mental processes and to measure mind wandering as a multifaceted rather than a unitary construct. PMID:29240817

Network Monitoring Traffic Compression Using Singular Value Decomposition

DTIC Science & Technology

2014-03-27

Shootouts." Workshop on Intrusion Detection and Network Monitoring. 1999. [12] Goodall , John R. "Visualization is better! a comparative evaluation...34 Visualization for Cyber Security, 2009. VizSec 2009. 6th International Workshop on IEEE, 2009. [13] Goodall , John R., and Mark Sowul. "VIAssist...Viruses and Log Visualization.” In Australian Digital Forensics Conference. Paper 54, 2008. [30] Tesone, Daniel R., and John R. Goodall . "Balancing

Visual Communications: Bridging Across Cultures. Selected Readings from the Annual Conference of the International Visual Literacy Association (23rd, Washington, D.C., October 1991).

ERIC Educational Resources Information Center

Baca, Judy Clark, Ed.; And Others

This book of readings consists of selected papers presented under five topics: (1) Research and Theory--18 papers including research on visual effects on attitude and cognition, students of different field dependence levels, modern and postmodern design on reader perceptions of news, effects of gray shades, short-term memory capacity differences,…

Perceived change in orientation from optic flow in the central visual field

NASA Technical Reports Server (NTRS)

Dyre, Brian P.; Andersen, George J.

1988-01-01

The effects of internal depth within a simulation display on perceived changes in orientation have been studied. Subjects monocularly viewed displays simulating observer motion within a volume of randomly positioned points through a window which limited the field of view to 15 deg. Changes in perceived spatial orientation were measured by changes in posture. The extent of internal depth within the display, the presence or absence of visual information specifying change in orientation, and the frequency of motion supplied by the display were examined. It was found that increased sway occurred at frequencies equal to or below 0.375 Hz when motion at these frequencies was displayed. The extent of internal depth had no effect on the perception of changing orientation.

Intermittent large amplitude internal waves observed in Port Susan, Puget Sound

NASA Astrophysics Data System (ADS)

Harris, J. C.; Decker, L.

2017-07-01

A previously unreported internal tidal bore, which evolves into solitary internal wave packets, was observed in Port Susan, Puget Sound, and the timing, speed, and amplitude of the waves were measured by CTD and visual observation. Acoustic Doppler current profiler (ADCP) measurements were attempted, but unsuccessful. The waves appear to be generated with the ebb flow along the tidal flats of the Stillaguamish River, and the speed and width of the resulting waves can be predicted from second-order KdV theory. Their eventual dissipation may contribute significantly to surface mixing locally, particularly in comparison with the local dissipation due to the tides. Visually the waves appear in fair weather as a strong foam front, which is less visible the farther they propagate.

Center for Advanced Modeling and Simulation Intern

ScienceCinema

Gertman, Vanessa

2017-12-13

Some interns just copy papers and seal envelopes. Not at INL! Check out how Vanessa Gertman, an INL intern working at the Center for Advanced Modeling and Simulation, spent her summer working with some intense visualization software. Lots more content like this is available at INL's facebook page http://www.facebook.com/idahonationallaboratory.

46 CFR 71.50-25 - Alternative Hull Examination (AHE) procedure.

Code of Federal Regulations, 2014 CFR

2014-10-01

... areas of the hull for examination, except internal tanks that carry fuel, sewage, or potable water. Internal tanks that carry fuel must be examined in accordance with § 71.53-1 of this part. Internal sewage and potable water tanks may be examined visually or by non-destructive testing to the satisfaction of...

46 CFR 71.50-25 - Alternative Hull Examination (AHE) procedure.

Code of Federal Regulations, 2013 CFR

2013-10-01

... areas of the hull for examination, except internal tanks that carry fuel, sewage, or potable water. Internal tanks that carry fuel must be examined in accordance with § 71.53-1 of this part. Internal sewage and potable water tanks may be examined visually or by non-destructive testing to the satisfaction of...

46 CFR 71.50-25 - Alternative Hull Examination (AHE) procedure.

Code of Federal Regulations, 2012 CFR

2012-10-01

... areas of the hull for examination, except internal tanks that carry fuel, sewage, or potable water. Internal tanks that carry fuel must be examined in accordance with § 71.53-1 of this part. Internal sewage and potable water tanks may be examined visually or by non-destructive testing to the satisfaction of...

46 CFR 71.50-25 - Alternative Hull Examination (AHE) procedure.

Code of Federal Regulations, 2011 CFR

2011-10-01

... areas of the hull for examination, except internal tanks that carry fuel, sewage, or potable water. Internal tanks that carry fuel must be examined in accordance with § 71.53-1 of this part. Internal sewage and potable water tanks may be examined visually or by non-destructive testing to the satisfaction of...

Center for Advanced Modeling and Simulation Intern

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gertman, Vanessa

Some interns just copy papers and seal envelopes. Not at INL! Check out how Vanessa Gertman, an INL intern working at the Center for Advanced Modeling and Simulation, spent her summer working with some intense visualization software. Lots more content like this is available at INL's facebook page http://www.facebook.com/idahonationallaboratory.

The internal representation of head orientation differs for conscious perception and balance control

PubMed Central

Dalton, Brian H.; Rasman, Brandon G.; Inglis, J. Timothy

2017-01-01

Key points We tested perceived head‐on‐feet orientation and the direction of vestibular‐evoked balance responses in passively and actively held head‐turned postures.The direction of vestibular‐evoked balance responses was not aligned with perceived head‐on‐feet orientation while maintaining prolonged passively held head‐turned postures. Furthermore, static visual cues of head‐on‐feet orientation did not update the estimate of head posture for the balance controller.A prolonged actively held head‐turned posture did not elicit a rotation in the direction of the vestibular‐evoked balance response despite a significant rotation in perceived angular head posture.It is proposed that conscious perception of head posture and the transformation of vestibular signals for standing balance relying on this head posture are not dependent on the same internal representation. Rather, the balance system may operate under its own sensorimotor principles, which are partly independent from perception. Abstract Vestibular signals used for balance control must be integrated with other sensorimotor cues to allow transformation of descending signals according to an internal representation of body configuration. We explored two alternative models of sensorimotor integration that propose (1) a single internal representation of head‐on‐feet orientation is responsible for perceived postural orientation and standing balance or (2) conscious perception and balance control are driven by separate internal representations. During three experiments, participants stood quietly while passively or actively maintaining a prolonged head‐turned posture (>10 min). Throughout the trials, participants intermittently reported their perceived head angular position, and subsequently electrical vestibular stimuli were delivered to elicit whole‐body balance responses. Visual recalibration of head‐on‐feet posture was used to determine whether static visual cues are used to update the internal representation of body configuration for perceived orientation and standing balance. All three experiments involved situations in which the vestibular‐evoked balance response was not orthogonal to perceived head‐on‐feet orientation, regardless of the visual information provided. For prolonged head‐turned postures, balance responses consistent with actual head‐on‐feet posture occurred only during the active condition. Our results indicate that conscious perception of head‐on‐feet posture and vestibular control of balance do not rely on the same internal representation, but instead treat sensorimotor cues in parallel and may arrive at different conclusions regarding head‐on‐feet posture. The balance system appears to bypass static visual cues of postural orientation and mainly use other sensorimotor signals of head‐on‐feet position to transform vestibular signals of head motion, a mechanism appropriate for most daily activities. PMID:28035656

DOE Office of Scientific and Technical Information (OSTI.GOV)

Winston, Philip Lon

Prior to performing an internal visual inspection, samples of the headspace gas of the GNS Castor V/21 cask were taken on June 12, 2014. These samples were taken in support of the CREIPI/Japanese nuclear industry effort to validate fuel integrity without visual inspection by measuring the 85Kr content of the cask headspace

Brilliant Blue G double staining enhances successful internal limiting membrane peeling with minimal adverse effect by low cellular permeability into live cells.

PubMed

Hisatomi, Toshio; Notomi, Shoji; Tachibana, Takashi; Oishi, Seiichiro; Asato, Ryo; Yamashita, Takehiro; Murakami, Yusuke; Ikeda, Yasuhiro; Enaida, Hiroshi; Sakamoto, Taiji; Ishibashi, Tatsuro

2015-02-01

Brilliant Blue G is used as a surgical adjuvant for retinal surgery. Although BBG double or multiple staining was reported, the effectiveness and safety of repeated staining is still elusive. To further examine the effectiveness and safety, we examined BBG in clinical cases in vivo, primary cell culture in vitro, and surgically resected specimen ex vivo. A retrospective interventional case series with in vitro and ex vivo studies were performed. Vitrectomy was performed in 28 cases of epiretinal membrane with BBG single to multiple staining. The surgically resected membranes were stained by BBG with or without cellular fixation. Primary cell cultures were examined with BBG and live/death cell markers, such as Calcein AM and TUNEL. Single staining provided satisfactory staining in seven cases. Double or multiple staining substantially visualized internal limiting membrane (21 cases), especially the edges of remaining internal limiting membrane (11 cases). Adverse retinal staining was not noted and the final visual acuity showed no difference with multiple staining. The live cells barely stained with BBG, while some dead cells were stained. Brilliant Blue G multiple staining substantially enhanced the visualization of internal limiting membrane. The absence of abnormal staining supports the safety of repeated BBG staining.

Relating Sensitivity and Criterion Effects to the Internal Mechanisms of Visual Spatial Attention

DTIC Science & Technology

1988-04-30

Hughes & Zimba , 1987; Rizzolatti, Riggio, Descola & *, .. Umilta, 1987). Further, deficits for uncued locations are a function 4. of the distance...Wilson, 1986; Rizzolatti, et. al., 1987; Hughes & Zimba , 1987, argue that this effect depends upon the use of an articulated visual field). Distance...Hughes, H. & Zimba , L. (1987) Nat,ral boundaries for the spatial spread of directed visual attention. Neuropsychologia, 25, 5-18. O Jonides, J. (1976

Laparoscopic omentoplasty to support anastomotic urethroplasty in complex and redo pelvic fracture urethral defects.

PubMed

Kulkarni, Sanjay B; Barbagli, Guido; Joshi, Pankaj M; Hunter, Craig; Shahrour, Walid; Kulkarni, Jyotsna; Sansalone, Salvatore; Lazzeri, Massimo

2015-05-01

To test the hypothesis that a new surgical technique using elaborated perineal anastomotic urethroplasty combined with laparoscopic omentoplasty for patients with complex and prior failed pelvic fracture urethral defect repair was feasible, safe, and effective. We performed a prospective, observational, stage 2a study to observe treatment outcomes of combined perineal and laparoscopic approach for urethroplasty in patients with pelvic fracture urethral defect at a single center in Pune, India, between January 2012 and February 2013. Complex and redo patients with pelvic fracture urethral defect occurring after pelvic fracture urethral injury were included in the study. Anterior urethral strictures were excluded. The primary study outcome was the success rate of the surgical technique, and the secondary outcome was to evaluate feasibility and safety of the procedure. The clinical outcome was considered a failure when any postoperative instrumentation was needed. Fifteen male patients with a median age of 19 years were included in the study. Seven patients were adolescents (12-18 years) and 8 patients (53.3%) were adults (19-49 years). The mean number of prior urethroplasties was 1.8 (range, 1-3). All patients underwent elaborated bulbomembranous anastomosis using a perineal approach with inferior pubectomy combined with laparoscopic mobilization of the omentum into the perineum to envelope the anastomosis and to fill the perineal dead space. Of 15 patients, 14 (93.3%) were successful and 1 (6.6%) failed. One adolescent boy 14 years old developed a recurrent stricture 2 months after the procedure and was managed using internal urethrotomy. Median follow-up was 18 months (range, 13-24 months). Combining a laparoscopic omentoplasty to a membranobulbar anastomosis for complex and redo pelvic fracture urethral injury is successful, feasible, safe, and with minimal additional morbidity to the patient. The technique has the advantage of a perineal incision and the ability to use the omentum to support the anastomosis. Copyright © 2015 Elsevier Inc. All rights reserved.

International Metadata Initiatives: Lessons in Bibliographic Control.

ERIC Educational Resources Information Center

Caplan, Priscilla

This paper looks at a subset of metadata schemes, including the Text Encoding Initiative (TEI) header, the Encoded Archival Description (EAD), the Dublin Core Metadata Element Set (DCMES), and the Visual Resources Association (VRA) Core Categories for visual resources. It examines why they developed as they did, major point of difference from…

Learning STEM through Integrative Visual Representations

ERIC Educational Resources Information Center

Virk, Satyugjit Singh

2013-01-01

Previous cognitive models of memory have not comprehensively taken into account the internal cognitive load of chunking isolated information and have emphasized the external cognitive load of visual presentation only. Under the Virk Long Term Working Memory Multimedia Model of cognitive load, drawing from the Cowan model, students presented with…

Non-Invasive Visualization and Quantitation of Cardiovascular Structure and Function.

ERIC Educational Resources Information Center

Ritman, E. L.; And Others

1979-01-01

Described is a new approach to investigative physiology based on computerized transaxial tomography, in which visualization and measurement of the internal structure of the cardiopulmonary system is possible without postmortem, biopsy, or vivisection procedures. Examples are given for application of the Dynamic Spatial Reconstructor (DSR). (CS)

Why Visual Literacy: Consciousness and Convention

ERIC Educational Resources Information Center

Rezabek, Landra L.

2005-01-01

In this article, the author discusses the intentions of the October 2005 Association for Educational Communications & Technology (AECT) conference. She explains that the conference will be a shared event between the AECT members and the participants of the 37th annual meeting of the International Visual Literacy Association (IVLA), a stalwart…

An expanded framework for biomolecular visualization in the classroom: Learning goals and competencies.

PubMed

Dries, Daniel R; Dean, Diane M; Listenberger, Laura L; Novak, Walter R P; Franzen, Margaret A; Craig, Paul A

2017-01-02

A thorough understanding of the molecular biosciences requires the ability to visualize and manipulate molecules in order to interpret results or to generate hypotheses. While many instructors in biochemistry and molecular biology use visual representations, few indicate that they explicitly teach visual literacy. One reason is the need for a list of core content and competencies to guide a more deliberate instruction in visual literacy. We offer here the second stage in the development of one such resource for biomolecular three-dimensional visual literacy. We present this work with the goal of building a community for online resource development and use. In the first stage, overarching themes were identified and submitted to the biosciences community for comment: atomic geometry; alternate renderings; construction/annotation; het group recognition; molecular dynamics; molecular interactions; monomer recognition; symmetry/asymmetry recognition; structure-function relationships; structural model skepticism; and topology and connectivity. Herein, the overarching themes have been expanded to include a 12th theme (macromolecular assemblies), 27 learning goals, and more than 200 corresponding objectives, many of which cut across multiple overarching themes. The learning goals and objectives offered here provide educators with a framework on which to map the use of molecular visualization in their classrooms. In addition, the framework may also be used by biochemistry and molecular biology educators to identify gaps in coverage and drive the creation of new activities to improve visual literacy. This work represents the first attempt, to our knowledge, to catalog a comprehensive list of explicit learning goals and objectives in visual literacy. © 2016 by The International Union of Biochemistry and Molecular Biology, 45(1):69-75, 2017. © 2016 The Authors Biochemistry and Molecular Biology Education published by Wiley Periodicals, Inc. on behalf of International Union of Biochemistry and Molecular Biology.

Objective automated quantification of fluorescence signal in histological sections of rat lens.

PubMed

Talebizadeh, Nooshin; Hagström, Nanna Zhou; Yu, Zhaohua; Kronschläger, Martin; Söderberg, Per; Wählby, Carolina

2017-08-01

Visual quantification and classification of fluorescent signals is the gold standard in microscopy. The purpose of this study was to develop an automated method to delineate cells and to quantify expression of fluorescent signal of biomarkers in each nucleus and cytoplasm of lens epithelial cells in a histological section. A region of interest representing the lens epithelium was manually demarcated in each input image. Thereafter, individual cell nuclei within the region of interest were automatically delineated based on watershed segmentation and thresholding with an algorithm developed in Matlab™. Fluorescence signal was quantified within nuclei, cytoplasms and juxtaposed backgrounds. The classification of cells as labelled or not labelled was based on comparison of the fluorescence signal within cells with local background. The classification rule was thereafter optimized as compared with visual classification of a limited dataset. The performance of the automated classification was evaluated by asking 11 independent blinded observers to classify all cells (n = 395) in one lens image. Time consumed by the automatic algorithm and visual classification of cells was recorded. On an average, 77% of the cells were correctly classified as compared with the majority vote of the visual observers. The average agreement among visual observers was 83%. However, variation among visual observers was high, and agreement between two visual observers was as low as 71% in the worst case. Automated classification was on average 10 times faster than visual scoring. The presented method enables objective and fast detection of lens epithelial cells and quantification of expression of fluorescent signal with an accuracy comparable with the variability among visual observers. © 2017 International Society for Advancement of Cytometry. © 2017 International Society for Advancement of Cytometry.

The development and validation of the Visual Analogue Self-Esteem Scale (VASES).

PubMed

Brumfitt, S M; Sheeran, P

1999-11-01

To develop a visual analogue measure of self-esteem and test its psychometric properties. Two correlational studies involving samples of university students and aphasic speakers. Two hundred and forty-three university students completed multiple measures of self-esteem, depression and anxiety as well as measures of transitory mood and social desirability (Study 1). Two samples of aphasic speakers (N = 14 and N = 20) completed the Visual Analogue Self-Esteem Scale (VASES), the Rosenberg (1965) self-esteem scale and measures of depression and anxiety. (Study 2). Study 1 found evidence of good internal and test-retest reliability, construct validity and convergent and discriminant validity for a 10-item VASES. Study 2 demonstrated good internal reliability among aphasic speakers. The VASES is a short and easy to administer measure of self-esteem that possesses good psychometric properties.

International Space Station Configuration Analysis and Integration

NASA Technical Reports Server (NTRS)

Anchondo, Rebekah

2016-01-01

Ambitious engineering projects, such as NASA's International Space Station (ISS), require dependable modeling, analysis, visualization, and robotics to ensure that complex mission strategies are carried out cost effectively, sustainably, and safely. Learn how Booz Allen Hamilton's Modeling, Analysis, Visualization, and Robotics Integration Center (MAVRIC) team performs engineering analysis of the ISS Configuration based primarily on the use of 3D CAD models. To support mission planning and execution, the team tracks the configuration of ISS and maintains configuration requirements to ensure operational goals are met. The MAVRIC team performs multi-disciplinary integration and trade studies to ensure future configurations meet stakeholder needs.

Cork Embedded Internal Features and Contrast Mechanisms with Del Using 18, 20, 30, 36 and 40 keV Synchrotron X-rays

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rao, D.V.; Zhong, Z.; Akatsuka, T.

Images of the cork used for wine and other bottles are visualized with the use of diffraction-enhanced imaging (DEI) technique. Present experimental studies allowed us to identify the cracks, holes, porosity, and importance of soft-matter (soft-material) and associated biology by visualization of the embedded internal complex features of the biological material such as cork and its microstructure. Highlighted the contrast mechanisms above and below the K-absorption edge of iodine and studied the attenuation through a combination of weakly and strongly attenuating materials.

Cork Embedded Internal Features and Contrast Mechanisms with DEI using 18, 20, 30, 36, and 40 kev Synchrotron X-rays

DOE Office of Scientific and Technical Information (OSTI.GOV)

Donepudi, R.; Cesareo, R; Brunetti, A

Images of the cork used for wine and other bottles are visualized with the use of diffraction-enhanced imaging (DEI) technique. Present experimental studies allowed us to identify the cracks, holes, porosity, and importance of soft-matter (soft-material) and associated biology by visualization of the embedded internal complex features of the biological material such as cork and its microstructure. Highlighted the contrast mechanisms above and below the K-absorption edge of iodine and studied the attenuation through a combination of weakly and strongly attenuating materials.

Vision in high-level football officials.

PubMed

Baptista, António Manuel Gonçalves; Serra, Pedro M; McAlinden, Colm; Barrett, Brendan T

2017-01-01

Officiating in football depends, at least to some extent, upon adequate visual function. However, there is no vision standard for football officiating and the nature of the relationship between officiating performance and level of vision is unknown. As a first step in characterising this relationship, we report on the clinically-measured vision and on the perceived level of vision in elite-level, Portuguese football officials. Seventy-one referees (R) and assistant referees (AR) participated in the study, representing 92% of the total population of elite level football officials in Portugal in the 2013/2014 season. Nine of the 22 Rs (40.9%) and ten of the 49 ARs (20.4%) were international-level. Information about visual history was also gathered. Perceived vision was assessed using the preference-values-assigned-to-global-visual-status (PVVS) and the Quality-of-Vision (QoV) questionnaire. Standard clinical vision measures (including visual acuity, contrast sensitivity and stereopsis) were gathered in a subset (n = 44, 62%) of the participants. Data were analysed according to the type (R/AR) and level (international/national) of official, and Bonferroni corrections were applied to reduce the risk of type I errors. Adopting criterion for statistical significance of p<0.01, PVVS scores did not differ between R and AR (p = 0.88), or between national- and international-level officials (p = 0.66). Similarly, QoV scores did not differ between R and AR in frequency (p = 0.50), severity (p = 0.71) or bothersomeness (p = 0.81) of symptoms, or between international-level vs national-level officials for frequency (p = 0.03) or bothersomeness (p = 0.07) of symptoms. However, international-level officials reported less severe symptoms than their national-level counterparts (p<0.01). Overall, 18.3% of officials had either never had an eye examination or if they had, it was more than 3 years previously. Regarding refractive correction, 4.2% had undergone refractive surgery and 23.9% wear contact lenses when officiating. Clinical vision measures in the football officials were similar to published normative values for young, adult populations and similar between R and AR. Clinically-measured vision did not differ according to officiating level. Visual acuity measured with and without a pinhole disc indicated that around one quarter of participants may be capable of better vision when officiating, as evidenced by better acuity (≥1 line of letters) using the pinhole. Amongst the clinical visual tests we used, we did not find evidence for above-average performance in elite-level football officials. Although the impact of uncorrected mild to moderate refractive error upon officiating performance is unknown, with a greater uptake of eye examinations, visual acuity may be improved in around a quarter of officials.

Vision in high-level football officials

PubMed Central

Serra, Pedro M.; McAlinden, Colm; Barrett, Brendan T.

2017-01-01

Officiating in football depends, at least to some extent, upon adequate visual function. However, there is no vision standard for football officiating and the nature of the relationship between officiating performance and level of vision is unknown. As a first step in characterising this relationship, we report on the clinically-measured vision and on the perceived level of vision in elite-level, Portuguese football officials. Seventy-one referees (R) and assistant referees (AR) participated in the study, representing 92% of the total population of elite level football officials in Portugal in the 2013/2014 season. Nine of the 22 Rs (40.9%) and ten of the 49 ARs (20.4%) were international-level. Information about visual history was also gathered. Perceived vision was assessed using the preference-values-assigned-to-global-visual-status (PVVS) and the Quality-of-Vision (QoV) questionnaire. Standard clinical vision measures (including visual acuity, contrast sensitivity and stereopsis) were gathered in a subset (n = 44, 62%) of the participants. Data were analysed according to the type (R/AR) and level (international/national) of official, and Bonferroni corrections were applied to reduce the risk of type I errors. Adopting criterion for statistical significance of p<0.01, PVVS scores did not differ between R and AR (p = 0.88), or between national- and international-level officials (p = 0.66). Similarly, QoV scores did not differ between R and AR in frequency (p = 0.50), severity (p = 0.71) or bothersomeness (p = 0.81) of symptoms, or between international-level vs national-level officials for frequency (p = 0.03) or bothersomeness (p = 0.07) of symptoms. However, international-level officials reported less severe symptoms than their national-level counterparts (p<0.01). Overall, 18.3% of officials had either never had an eye examination or if they had, it was more than 3 years previously. Regarding refractive correction, 4.2% had undergone refractive surgery and 23.9% wear contact lenses when officiating. Clinical vision measures in the football officials were similar to published normative values for young, adult populations and similar between R and AR. Clinically-measured vision did not differ according to officiating level. Visual acuity measured with and without a pinhole disc indicated that around one quarter of participants may be capable of better vision when officiating, as evidenced by better acuity (≥1 line of letters) using the pinhole. Amongst the clinical visual tests we used, we did not find evidence for above-average performance in elite-level football officials. Although the impact of uncorrected mild to moderate refractive error upon officiating performance is unknown, with a greater uptake of eye examinations, visual acuity may be improved in around a quarter of officials. PMID:29161310

Construction and validation of a Tamil logMAR chart.

PubMed

Varadharajan, Srinivasa; Srinivasan, Krithica; Kumaresan, Brindha

2009-09-01

To design, construct and validate a new Tamil logMAR visual acuity chart based on current recommendations. Ten Tamil letters of equal legibility were identified experimentally and were used in the chart. Two charts, one internally illuminated and one externally illuminated, were constructed for testing at 4 m distance. The repeatability of the two charts was tested. For validation, the two charts were compared with a standard English logMAR chart (ETDRS). When compared to the ETDRS chart, a difference of 0.06 +/- 0.07 and 0.07 +/- 0.07 logMAR was found for the internally and externally illuminated charts respectively. Limits of agreement between the internally illuminated Tamil logMAR chart and ETDRS chart were found to be (-0.08, 0.19), and (-0.07, 0.20) for the externally illuminated chart. The test - retest results showed a difference of 0.02 +/- 0.04 and 0.02 +/- 0.06 logMAR for the internally and externally illuminated charts respectively. Limits of agreement for repeated measurements for the internally illuminated Tamil logMAR chart were found to be (-0.06, 0.10), and (-0.10, 0.14) for the externally illuminated chart. The newly constructed Tamil logMAR charts have good repeatability. The difference in visual acuity scores between the newly constructed Tamil logMAR chart and the standard English logMAR chart was within acceptable limits. This new chart can be used for measuring visual acuity in the literate Tamil population.

Plant photonics: application of optical coherence tomography to monitor defects and rots in onion

NASA Astrophysics Data System (ADS)

Meglinski, I. V.; Buranachai, C.; Terry, L. A.

2010-04-01

The incidence of physiological and/or pathological defects in many fresh produce types is still unacceptably high and accounts for a large proportion of waste. With increasing interest in food security their remains strong demand in developing reliable and cost effective technologies for non-destructive screening of internal defects and rots, these being deemed unacceptable by consumers. It is well recognized that the internal defects and structure of turbid scattering media can be effectively visualized by using optical coherence tomography (OCT). In the present study, the high spatial resolution and advantages of OCT have been demonstrated for imaging the skins and outer laminae (concentric tissue layers) of intact whole onion bulbs with a view to non-invasively visualizing potential incidence/severity of internal defects.

Symphysiotomy: a viable approach for delayed management of posterior urethral injuries in children.

PubMed

Basiri, Abbas; Shadpour, Pejman; Moradi, Mahmood Reza; Ahmadinia, Hossein; Madaen, Kazem

2002-11-01

The outcome of symphysiotomy for accessing pelvic fracture related, obliterative urethral strictures is described. In 7 boys and 3 girls 4 to 13 years old (mean age 6) surgical correction of a pelvic fracture related, obliterative urethral stricture was achieved through symphysiotomy. The stricture involved a prostatomembranous location in boys and complete vesicourethral distraction in girls. Patients were followed an average of 2.5 years (range 6 months to 4 years) by physical examination, urethrography and endoscopy. The stricture was successfully corrected in all patients and all void with a normal flow. All boys are continent but 2 of the 3 girls had early incontinence, which resolved with time in 1. In 2 of the 10 cases a previous attempt at perineal repair had already failed. No patient required urethrotomy or dilation and none had significant hemorrhage, fistulization, bladder hernia, chronic pain or secondary gait disturbance. Symphysiotomy is hereby revisited as a simple and effective approach for repairing traumatic posterior urethral injuries in the pediatric population. It can be performed instead of transpubic urethroplasty to manage long or otherwise complicated strictures.

The shaping of information by visual metaphors.

PubMed

Ziemkiewicz, Caroline; Kosara, Robert

2008-01-01

The nature of an information visualization can be considered to lie in the visual metaphors it uses to structure information. The process of understanding a visualization therefore involves an interaction between these external visual metaphors and the user's internal knowledge representations. To investigate this claim, we conducted an experiment to test the effects of visual metaphor and verbal metaphor on the understanding of tree visualizations. Participants answered simple data comprehension questions while viewing either a treemap or a node-link diagram. Questions were worded to reflect a verbal metaphor that was either compatible or incompatible with the visualization a participant was using. The results (based on correctness and response time) suggest that the visual metaphor indeed affects how a user derives information from a visualization. Additionally, we found that the degree to which a user is affected by the metaphor is strongly correlated with the user's ability to answer task questions correctly. These findings are a first step towards illuminating how visual metaphors shape user understanding, and have significant implications for the evaluation, application, and theory of visualization.

Direction of attentional focus in biofeedback treatment for /r/ misarticulation.

PubMed

McAllister Byun, Tara; Swartz, Michelle T; Halpin, Peter F; Szeredi, Daniel; Maas, Edwin

2016-07-01

Maintaining an external direction of focus during practice is reported to facilitate acquisition of non-speech motor skills, but it is not known whether these findings also apply to treatment for speech errors. This question has particular relevance for treatment incorporating visual biofeedback, where clinician cueing can direct the learner's attention either internally (i.e., to the movements of the articulators) or externally (i.e., to the visual biofeedback display). This study addressed two objectives. First, it aimed to use single-subject experimental methods to collect additional evidence regarding the efficacy of visual-acoustic biofeedback treatment for children with /r/ misarticulation. Second, it compared the efficacy of this biofeedback intervention under two cueing conditions. In the external focus (EF) condition, participants' attention was directed exclusively to the external biofeedback display. In the internal focus (IF) condition, participants viewed a biofeedback display, but they also received articulatory cues encouraging an internal direction of attentional focus. Nine school-aged children were pseudo-randomly assigned to receive either IF or EF cues during 8 weeks of visual-acoustic biofeedback intervention. Accuracy in /r/ production at the word level was probed in three to five pre-treatment baseline sessions and in three post-treatment maintenance sessions. Outcomes were assessed using visual inspection and calculation of effect sizes for individual treatment trajectories. In addition, a mixed logistic model was used to examine across-subjects effects including phase (pre/post-treatment), /r/ variant (treated/untreated), and focus cue condition (internal/external). Six out of nine participants showed sustained improvement on at least one treated /r/ variant; these six participants were evenly divided across EF and IF treatment groups. Regression results indicated that /r/ productions were significantly more likely to be rated accurate post- than pre-treatment. Internal versus external direction of focus cues was not a significant predictor of accuracy, nor did it interact significantly with other predictors. The results are consistent with previous literature reporting that visual-acoustic biofeedback can produce measurable treatment gains in children who have not responded to previous intervention. These findings are also in keeping with previous research suggesting that biofeedback may be sufficient to establish an external attentional focus, independent of verbal cues provided. The finding that explicit articulator placement cues were not necessary for progress in treatment has implications for intervention practices for speech-sound disorders in children. © 2016 Royal College of Speech and Language Therapists.

Vitrectomy with internal limiting membrane peeling versus inverted internal limiting membrane flap technique for macular hole-induced retinal detachment: a systematic review of literature and meta-analysis.

PubMed

Yuan, Jing; Zhang, Ling-Lin; Lu, Yu-Jie; Han, Meng-Yao; Yu, Ai-Hua; Cai, Xiao-Jun

2017-11-28

To evaluate the effects on vitrectomy with internal limiting membrane (ILM) peeling versus vitrectomy with inverted internal limiting membrane flap technique for macular hole-induced retinal detachment (MHRD). Pubmed, Cochrane Library, and Embase were systematically searched for studies that compared ILM peeling with inverted ILM flap technique for macular hole-induced retinal detachment. The primary outcomes are the rate of retinal reattachment and the rate of macular hole closure 6 months later after initial surgery, the secondary outcome is the postoperative best-corrected visual acuity (BCVA) 6 months later after initial surgery. Four studies that included 98 eyes were selected. All the included studies were retrospective comparative studies. The preoperative best-corrected visual acuity was equal between ILM peeling and inverted ILM flap technique groups. It was indicated that the rate of retinal reattachment (odds ratio (OR) = 0.14, 95% confidence interval (CI):0.03 to 0.69; P = 0.02) and macular hole closure (OR = 0.06, 95% CI:0.02 to 0.19; P < 0.00001) after initial surgery was higher in the group of vitrectomy with inverted ILM flap technique than that in the group of vitrectomy with ILM peeling. However, there was no statistically significant difference in postoperative best-corrected visual acuity (mean difference (MD) 0.18 logarithm of the minimum angle of resolution; 95% CI -0.06 to 0.43 ; P = 0.14) between the two surgery groups. Compared with ILM peeling, vitrectomy with inverted ILM flap technique resulted significantly higher of the rate of retinal reattachment and macular hole closure, but seemed does not improve postoperative best-corrected visual acuity.

A Visual Means of Organizing Career Information.

ERIC Educational Resources Information Center

Amundson, Norman E.

1987-01-01

Describes a visual means, the centric system, of organizing career information which allows clients to consider a number of external and internal factors and their relative importance. Takes into account psychological, social, and economic factors and is consistent with a view of work as one part of a total life style. (Author/ABB)

Primary School Pupils' Response to Audio-Visual Learning Process in Port-Harcourt

ERIC Educational Resources Information Center

Olube, Friday K.

2015-01-01

The purpose of this study is to examine primary school children's response on the use of audio-visual learning processes--a case study of Chokhmah International Academy, Port-Harcourt (owned by Salvation Ministries). It looked at the elements that enhance pupils' response to educational television programmes and their hindrances to these…

Perceptual Factors Influence Visual Search for Meaningful Symbols in Individuals with Intellectual Disabilities and Down Syndrome or Autism Spectrum Disorders

ERIC Educational Resources Information Center

Wilkinson, Krista M.; McIlvane, William J.

2013-01-01

Augmentative and alternative communication (AAC) systems often supplement oral communication for individuals with intellectual and communication disabilities. Research with preschoolers without disabilities has demonstrated that two visual--perceptual factors influence speed and/or accuracy of finding a target: the internal color and spatial…

Inside the Gray of Gang: Reflections on the Arts and Youth Violence

ERIC Educational Resources Information Center

Jackson, Renee

2006-01-01

Visual literacy contains a vat of underlying understanding that fuses to the bones of students who actively pursue an art education. For everything visible, there is an invisible internal counterpart, and arts education provides vital depth that is currently being drained from Canadian culture. Visual literacy begins with the elements and…

(En)Countering Social and Environmental Messages in the Rainforest Cafe [sic], Children's Picturebooks, and Other Visual Culture Sites

ERIC Educational Resources Information Center

Reisberg, Mira; Han, Sandrine

2009-01-01

Our study critically examines social and environmental messages in a range of visual sites educating about rainforest environments. We focus primarily on the Rainforest Cafe, an international series of rainforest-themed edutainment restaurant/stores, whose inherent contradictions between consumption and conservation are quite disturbing when…

Caught in the Betwixt-and-Between: Visual Narrative of an Asian Artist-Scholar

ERIC Educational Resources Information Center

Kan, Koon Hwee

2009-01-01

Juxtaposing visual images with stories, this work addresses the formation of my transnational identity and my experience in the "betwixt-and-between," illustrating my struggles as artist, scholar, and international faculty member at an Anglo American university. I exacerbate tensions between my professional and attributed identities to complicate…

Optical Flow-Based State Estimation for Guided Projectiles

DTIC Science & Technology

2015-06-01

Computer Vision and Image Understanding. 2012;116(5):606–633. 3. Corke P, Lobo J, Dias J. An introduction to inertial and visual sensing. The...International Journal of Robotics Research. 2007;26(6):519–535. 4. Hutchinson S, Hager GD, Corke PI. A tutorial on visual servo control. Robotics and

Spatial Visualization as Mediating between Mathematics Learning Strategy and Mathematics Achievement among 8th Grade Students

ERIC Educational Resources Information Center

Rabab'h, Belal; Veloo, Arsaythamby

2015-01-01

Jordanian 8th grade students revealed low achievement in mathematics through four periods (1999, 2003, 2007 & 2011) of Trends in International Mathematics and Science Study (TIMSS). This study aimed to determine whether spatial visualization mediates the affect of Mathematics Learning Strategies (MLS) factors namely mathematics attitude,…

Eccentric Macular Hole after Pars Plana Vitrectomy for Epiretinal Membrane Without Internal Limiting Membrane Peeling: A Case Report.

PubMed

Garnavou-Xirou, Christina; Xirou, Tina; Kabanarou, Stamatina; Gkizis, Ilias; Velissaris, Stavros; Chatziralli, Irini

2017-12-01

Postoperative eccentric macular hole formation is an uncommon complication after pars plana vitrectomy (PPV) without internal limiting membrane (ILM) peeling for the treatment of epiretinal membrane (ERM). We present a case of eccentric macular hole formation after PPV for ERM without ILM peeling. A 68-year-old male patient presented with ERM and visual acuity of 6/24 in his left eye. He underwent 23-gauge PPV without ILM peeling for treatment of ERM. One week postoperatively the retina was attached and the epiretinal membrane was successfully removed, while visual acuity was 6/9. One month after PPV, a single eccentric retinal hole below the macula was detected using fundoscopy and subsequently confirmed by optical coherence tomography. At this time the visual acuity was 6/9 and the patient reported no symptoms. No further intervention was attempted and at the 9-month follow-up, the visual acuity and the size of the eccentric macular hole remained stable. Eccentric macular holes can be developed after PPV even without ILM peeling and are usually managed conservatively by observation.

Intercepting a sound without vision

PubMed Central

Vercillo, Tiziana; Tonelli, Alessia; Gori, Monica

2017-01-01

Visual information is extremely important to generate internal spatial representations. In the auditory modality, the absence of visual cues during early infancy does not preclude the development of some spatial strategies. However, specific spatial abilities might result impaired. In the current study, we investigated the effect of early visual deprivation on the ability to localize static and moving auditory stimuli by comparing sighted and early blind individuals’ performance in different spatial tasks. We also examined perceptual stability in the two groups of participants by matching localization accuracy in a static and a dynamic head condition that involved rotational head movements. Sighted participants accurately localized static and moving sounds. Their localization ability remained unchanged after rotational movements of the head. Conversely, blind participants showed a leftward bias during the localization of static sounds and a little bias for moving sounds. Moreover, head movements induced a significant bias in the direction of head motion during the localization of moving sounds. These results suggest that internal spatial representations might be body-centered in blind individuals and that in sighted people the availability of visual cues during early infancy may affect sensory-motor interactions. PMID:28481939

The Benefits of Internal Thoracic Artery Catheterization in Patients With Chronic Abdominal Aortic Occlusion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ilic, Nikola, E-mail: fosafosa75@yahoo.com; Davidovic, Lazar; Koncar, Igor

Occlusion of the abdominal aorta may be caused by an embolic lesion, but more commonly by thrombotic disease at the aortoiliac area, progressing retrograde. However, the visualization of the distal run-off via internal thoracic-epigastric inferior artery collateral channel may be a very important diagnostic tool, especially in countries with poor technical equipment. This study was designed to show the benefit of the selective internal thoracic angiography in cases with complete aortic occlusion. We present 30 patients with chronic aortic abdominal occlusion who were submitted to the transaxillary aortography and selective ITA angiography with purpose of distal run off evaluation. Angiographicmore » evaluation was performed by two independent radiologists according to previously defined classification. Good angiographic score via internal thoracic angiography by first observer was achieved in 19 (63.3%) patients and in 18 (60%) by a second observer. Transaxillary aortography showed inferior results: good angiographic score by the first observer in six (20%) patients and by the second observer in three (3%) patients. Low extremity run-off is better visualized during internal thoracic angiography than during transaxillary aortography.« less

Cardinal rules: Visual orientation perception reflects knowledge of environmental statistics

PubMed Central

Girshick, Ahna R.; Landy, Michael S.; Simoncelli, Eero P.

2011-01-01

Humans are remarkably good at performing visual tasks, but experimental measurements reveal substantial biases in the perception of basic visual attributes. An appealing hypothesis is that these biases arise through a process of statistical inference, in which information from noisy measurements is fused with a probabilistic model of the environment. But such inference is optimal only if the observer’s internal model matches the environment. Here, we provide evidence that this is the case. We measured performance in an orientation-estimation task, demonstrating the well-known fact that orientation judgements are more accurate at cardinal (horizontal and vertical) orientations, along with a new observation that judgements made under conditions of uncertainty are strongly biased toward cardinal orientations. We estimate observers’ internal models for orientation and find that they match the local orientation distribution measured in photographs. We also show how a neural population could embed probabilistic information responsible for such biases. PMID:21642976

Looking for Creativity: Where Do We Look When We Look for New Ideas?

PubMed Central

Salvi, Carola; Bowden, Edward M.

2016-01-01

Recent work using the eye movement monitoring technique has demonstrated that when people are engaged in thought they tend to disengage from the external world by blinking or fixating on an empty portion of the visual field, such as a blank wall, or out the window at the sky. This ‘looking at nothing’ behavior has been observed during thinking that does not explicitly involve visual imagery (mind wandering, insight in problem solving, memory encoding and search) and it is associated with reduced analysis of the external visual environment. Thus, it appears to indicate (and likely facilitate) a shift of attention from external to internal stimuli that benefits creativity and problem solving by reducing the cognitive load and enhancing attention to internally evolving activation. We briefly mention some possible reasons to collect eye movement data in future studies of creativity. PMID:26913018

Ophthalmic public health; the way ahead.

PubMed

Heidary, F; Rahimi, A; Gharebaghi, R

2012-01-01

Visual sciences have been progressing quickly in recent decades through globalization phenomenon. An enormous change has taken place in ocular health issues, however, there are various problems facing ophthalmic public health worldwide. In the previous years, the World Health Organization and the International Agency for the Prevention of Blindness in partnership launched the global initiative to eradicate avoidable blindness by the year 2020, VISION 2020 the Right to Sight. It has concentrated on the prevention of blindness disability and recognized a health issue-sight as a human right. In view of challenges ahead of visual sciences, close collaboration between international agencies at the global level to implement new strategies and monitor the progress will be mandatory. In these circumstances non-governmental organizations should not be neglected. World Sight Day 2012 would be a great opportunity to be a focus on importance of visual impairment as an important public health issue and discovering new challenges ahead.

Special Issue of Selected Papers from Visualization and Data Analysis 2011

NASA Technical Reports Server (NTRS)

Kao, David L.; Wong, Pak Chung

2012-01-01

This special issue features the best papers that were selected from the 18th SPIE Conference on Visualization and Data Analysis (VDA 2011). This annual conference is a major international forum for researchers and practitioners interested in data visualization and analytics research, development, and applications. VDA 2011 received 42 high-quality submissions from around the world. Twenty-four papers were selected for full conference papers. The top five papers have been expanded and reviewed for this special issue.

Development of visual programming techniques to integrate theoretical modeling into the scientific planning and instrument operations environment of ISTP

NASA Technical Reports Server (NTRS)

Goodrich, Charles C.

1993-01-01

The goal of this project is to investigate the use of visualization software based on the visual programming and data-flow paradigms to meet the needs of the SPOF and through it the International Solar Terrestrial Physics (ISTP) science community. Specific needs we address include science planning, data interpretation, comparisons of data with simulation and model results, and data acquisition. Our accomplishments during the twelve month grant period are discussed below.

The internal representation of head orientation differs for conscious perception and balance control.

PubMed

Dalton, Brian H; Rasman, Brandon G; Inglis, J Timothy; Blouin, Jean-Sébastien

2017-04-15

We tested perceived head-on-feet orientation and the direction of vestibular-evoked balance responses in passively and actively held head-turned postures. The direction of vestibular-evoked balance responses was not aligned with perceived head-on-feet orientation while maintaining prolonged passively held head-turned postures. Furthermore, static visual cues of head-on-feet orientation did not update the estimate of head posture for the balance controller. A prolonged actively held head-turned posture did not elicit a rotation in the direction of the vestibular-evoked balance response despite a significant rotation in perceived angular head posture. It is proposed that conscious perception of head posture and the transformation of vestibular signals for standing balance relying on this head posture are not dependent on the same internal representation. Rather, the balance system may operate under its own sensorimotor principles, which are partly independent from perception. Vestibular signals used for balance control must be integrated with other sensorimotor cues to allow transformation of descending signals according to an internal representation of body configuration. We explored two alternative models of sensorimotor integration that propose (1) a single internal representation of head-on-feet orientation is responsible for perceived postural orientation and standing balance or (2) conscious perception and balance control are driven by separate internal representations. During three experiments, participants stood quietly while passively or actively maintaining a prolonged head-turned posture (>10 min). Throughout the trials, participants intermittently reported their perceived head angular position, and subsequently electrical vestibular stimuli were delivered to elicit whole-body balance responses. Visual recalibration of head-on-feet posture was used to determine whether static visual cues are used to update the internal representation of body configuration for perceived orientation and standing balance. All three experiments involved situations in which the vestibular-evoked balance response was not orthogonal to perceived head-on-feet orientation, regardless of the visual information provided. For prolonged head-turned postures, balance responses consistent with actual head-on-feet posture occurred only during the active condition. Our results indicate that conscious perception of head-on-feet posture and vestibular control of balance do not rely on the same internal representation, but instead treat sensorimotor cues in parallel and may arrive at different conclusions regarding head-on-feet posture. The balance system appears to bypass static visual cues of postural orientation and mainly use other sensorimotor signals of head-on-feet position to transform vestibular signals of head motion, a mechanism appropriate for most daily activities. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

The theoretical cognitive process of visualization for science education.

PubMed

Mnguni, Lindelani E

2014-01-01

The use of visual models such as pictures, diagrams and animations in science education is increasing. This is because of the complex nature associated with the concepts in the field. Students, especially entrant students, often report misconceptions and learning difficulties associated with various concepts especially those that exist at a microscopic level, such as DNA, the gene and meiosis as well as those that exist in relatively large time scales such as evolution. However the role of visual literacy in the construction of knowledge in science education has not been investigated much. This article explores the theoretical process of visualization answering the question "how can visual literacy be understood based on the theoretical cognitive process of visualization in order to inform the understanding, teaching and studying of visual literacy in science education?" Based on various theories on cognitive processes during learning for science and general education the author argues that the theoretical process of visualization consists of three stages, namely, Internalization of Visual Models, Conceptualization of Visual Models and Externalization of Visual Models. The application of this theoretical cognitive process of visualization and the stages of visualization in science education are discussed.

Visual affective classification by combining visual and text features.

PubMed

Liu, Ningning; Wang, Kai; Jin, Xin; Gao, Boyang; Dellandréa, Emmanuel; Chen, Liming

2017-01-01

Affective analysis of images in social networks has drawn much attention, and the texts surrounding images are proven to provide valuable semantic meanings about image content, which can hardly be represented by low-level visual features. In this paper, we propose a novel approach for visual affective classification (VAC) task. This approach combines visual representations along with novel text features through a fusion scheme based on Dempster-Shafer (D-S) Evidence Theory. Specifically, we not only investigate different types of visual features and fusion methods for VAC, but also propose textual features to effectively capture emotional semantics from the short text associated to images based on word similarity. Experiments are conducted on three public available databases: the International Affective Picture System (IAPS), the Artistic Photos and the MirFlickr Affect set. The results demonstrate that the proposed approach combining visual and textual features provides promising results for VAC task.

Visual affective classification by combining visual and text features

PubMed Central

Liu, Ningning; Wang, Kai; Jin, Xin; Gao, Boyang; Dellandréa, Emmanuel; Chen, Liming

2017-01-01

Affective analysis of images in social networks has drawn much attention, and the texts surrounding images are proven to provide valuable semantic meanings about image content, which can hardly be represented by low-level visual features. In this paper, we propose a novel approach for visual affective classification (VAC) task. This approach combines visual representations along with novel text features through a fusion scheme based on Dempster-Shafer (D-S) Evidence Theory. Specifically, we not only investigate different types of visual features and fusion methods for VAC, but also propose textual features to effectively capture emotional semantics from the short text associated to images based on word similarity. Experiments are conducted on three public available databases: the International Affective Picture System (IAPS), the Artistic Photos and the MirFlickr Affect set. The results demonstrate that the proposed approach combining visual and textual features provides promising results for VAC task. PMID:28850566

Reliability and validity of generalizable skills instruments for students who are deaf, blind, or visually impaired.

PubMed

Loeding, B L; Greenan, J P

1998-12-01

The study examined the validity and reliability of four assessments, with three instruments per domain. Domains included generalizable mathematics, communication, interpersonal relations, and reasoning skills. Participants were deaf, legally blind, or visually impaired students enrolled in vocational classes at residential secondary schools. The researchers estimated the internal consistency reliability, test-retest reliability, and construct validity correlations of three subinstruments: student self-ratings, teacher ratings, and performance assessments. The data suggest that these instruments are highly internally consistent measures of generalizable vocational skills. Four performance assessments have high-to-moderate test-retest reliability estimates, and were generally considered to possess acceptable validity and reliability.

A Presentation of Spectracular Visualizations

NASA Technical Reports Server (NTRS)

Hasler, Fritz; Pierce, Hal; Einaudi, Franco (Technical Monitor)

2000-01-01

The NASA/NOAA/AMS Earth Science Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to Florida and the KSC Visitor's Center. Go back to the early weather satellite images from the 1960s see them contrasted with the latest International global satellite weather movies including killer hurricanes & tornadic thunderstorms. See the latest spectacular images from NASA and NOAA remote sensing missions like GOES, NOAA, TRMM, SeaWiFS, Landsat7, & new Terra which will be visualized with state-of-the art tools. Shown in High Definition TV resolution (2048 x 768 pixels) are visualizations of hurricanes Lenny, Floyd, Georges, Mitch, Fran and Linda. See visualizations featured on covers of magazines like Newsweek, TIME, National Geographic, Popular Science and on National & International Network TV. New Digital Earth visualization tools allow us to roam & zoom through massive global images including a Landsat tour of the US, with drill-downs into major cities using I m resolution spy-satellite technology from the Space Imaging IKONOS satellite. Spectacular new visualizations of the global atmosphere & oceans are shown. See massive dust storms sweeping across Africa. See ocean vortexes and currents that bring up the nutrients to feed tiny plankton and draw the fish, giant whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. The demonstration is interactively driven by a SGI Octane Graphics Supercomputer with dual CPUs, 5 Gigabytes of RAM and Terabyte disk using two projectors across the super sized Universe Theater panoramic screen.

A Presentation of Spectacular Visualizations. Visions of Our Planet's Atmosphere, Land and Oceans: ETheater Presentation

NASA Technical Reports Server (NTRS)

Hasler, Fritz; Pierce, Hal; Einaudi, Franco (Technical Monitor)

2000-01-01

The NASA/NOAA/AMS Earth Science Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to Florida and the KSC Visitor's Center. Go back to the early weather satellite images from the 1960s see them contrasted with the latest International global satellite weather movies including killer hurricanes & tornadic thunderstorms. See the latest spectacular images from NASA and NOAA remote sensing missions like GOES, NOAA, TRMM, SeaWiFS, Landsat7, & new Terra which will be visualized with state-of-the art tools. Shown in High Definition TV resolution (2048 x 768 pixels) are visualizations of hurricanes Lenny, Floyd, Georges, Mitch, Fran and Linda. See visualizations featured on covers of magazines like Newsweek, TIME, National Geographic, Popular Science and on National & International Network TV. New Digital Earth visualization tools allow us to roam & zoom through massive global images including a Landsat tour of the US, with drill-downs into major cities using 1 m resolution spy-satellite technology from the Space Imaging IKONOS satellite. Spectacular new visualizations of the global atmosphere & oceans are shown. See massive dust storms sweeping across Africa. See ocean vortices and currents that bring up the nutrients to feed tiny plankton and draw the fish, giant whales and fisherman. See how the ocean blooms in response to these currents and El Nino/La Nina climate changes. The demonstration is interactively driven by a SGI Octane Graphics Supercomputer with dual CPUs, 5 Gigabytes of RAM and Terabyte disk using two projectors across the super sized Universe Theater panoramic screen.

Global Positioning System Synchronized Active Light Autonomous Docking System

NASA Technical Reports Server (NTRS)

Howard, Richard T. (Inventor); Book, Michael L. (Inventor); Bryan, Thomas C. (Inventor); Bell, Joseph L. (Inventor)

1996-01-01

A Global Positioning System Synchronized Active Light Autonomous Docking System (GPSSALADS) for automatically docking a chase vehicle with a target vehicle comprising at least one active light emitting target which is operatively attached to the target vehicle. The target includes a three-dimensional array of concomitantly flashing lights which flash at a controlled common frequency. The GPSSALADS further comprises a visual tracking sensor operatively attached to the chase vehicle for detecting and tracking the target vehicle. Its performance is synchronized with the flash frequency of the lights by a synchronization means which is comprised of first and second internal clocks operatively connected to the active light target and visual tracking sensor, respectively, for providing timing control signals thereto, respectively. The synchronization means further includes first and second Global Positioning System receivers operatively connected to the first and second internal clocks, respectively, for repeatedly providing simultaneous synchronization pulses to the internal clocks, respectively. In addition, the GPSSALADS includes a docking process controller means which is operatively attached to the chase vehicle and is responsive to the visual tracking sensor for producing commands for the guidance and propulsion system of the chase vehicle.

Global Positioning System Synchronized Active Light Autonomous Docking System

NASA Technical Reports Server (NTRS)

Howard, Richard (Inventor)

1994-01-01

A Global Positioning System Synchronized Active Light Autonomous Docking System (GPSSALADS) for automatically docking a chase vehicle with a target vehicle comprises at least one active light emitting target which is operatively attached to the target vehicle. The target includes a three-dimensional array of concomitantly flashing lights which flash at a controlled common frequency. The GPSSALADS further comprises a visual tracking sensor operatively attached to the chase vehicle for detecting and tracking the target vehicle. Its performance is synchronized with the flash frequency of the lights by a synchronization means which is comprised of first and second internal clocks operatively connected to the active light target and visual tracking sensor, respectively, for providing timing control signals thereto, respectively. The synchronization means further includes first and second Global Positioning System receivers operatively connected to the first and second internal clocks, respectively, for repeatedly providing simultaneous synchronization pulses to the internal clocks, respectively. In addition, the GPSSALADS includes a docking process controller means which is operatively attached to the chase vehicle and is responsive to the visual tracking sensor for producing commands for the guidance and propulsion system of the chase vehicle.

Antineutrophil cytoplasmic antibody-associated vasculitides: a scientometric approach visualizing worldwide research activity.

PubMed

Gerber, Alexander; Klingelhoefer, Doris; Groneberg, David; Bundschuh, Matthias

2014-09-01

To provide a critical evaluation of quality and quantity regarding scientific efforts on antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) during the past 20 years. Scientometric benchmark procedures, density-equalizing mapping and large-scale data analysis were used to visualize bi- and multilateral research cooperation and institutional collaborations, and to identify the most successful countries, institutions, authors and journals concerned with AAV. The USA are the most productive supplier and have established their position as center of international cooperation with 22.5% of all publications, followed by Germany, the United Kingdom, France and Japan, respectively. The most successful international cooperation proved to be the one between the USA, Germany and the UK. A distinct global pattern of research productivity and citation activity was revealed, with the USA and Germany holding both the highest h-index and the highest number of total citations, but Denmark, Sweden and the Netherlands leading with regards to the citation rate. Some large and productive countries such as Japan, China and Turkey show only a few international cooperations. The present study represents the first detailed scientometric analysis and visualization of research quality and quantity on 'ANCA- associated vasculitides'. It was shown that scientometric indicators such as h-index, citation rate and impact factor, commonly used for assessment of scientific quality, have to be seen critically due to distortion by self-citation, co-authorship and language bias. Countries with considerable numbers of patients should enhance international collaboration behavior for the benefit of international scientific and clinical progress. © 2014 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

Maintenance Procedures for North American Visually-graded Dimension Lumber Design Values

Treesearch

David Kretschmann; Don DeVisser; Kevin Cheung; Bob Browder; Al Rozek

2014-01-01

ASTM International D1990 Standard Practice for Establishing Allowable Properties for Visually-Graded Dimension Lumber from In-Grade Tests of Full-Size Specimens, that governs the development of design values for dimension lumber in North America, was first adopted in 1991with recognition that the resource and manufacturing of lumber could change over time impacting...

Effect of methyl salicylate and methyl jasmonate pre-treatment on the volatile profile in tomato fruit subjected to chilling temperature

USDA-ARS?s Scientific Manuscript database

Tomato fruits exposed to chilling temperatures suffer aroma loss prior to visual chilling injury (CI) symptoms. Methyl salicylate (MeSA) and methyl jasmonate (MeJA) treatments were reported to alleviate the development of visual CI, however, it is unknown if the treatments alleviate internal CI in t...

From Vesalius to Virtual Reality: How Embodied Cognition Facilitates the Visualization of Anatomy

ERIC Educational Resources Information Center

Jang, Susan

2010-01-01

This study examines the facilitative effects of embodiment of a complex internal anatomical structure through three-dimensional ("3-D") interactivity in a virtual reality ("VR") program. Since Shepard and Metzler's influential 1971 study, it has been known that 3-D objects (e.g., multiple-armed cube or external body parts) are visually and…

Supporting the Teaching of the Visual Literacies in the Earth and Life Sciences in Higher Education

ERIC Educational Resources Information Center

Paxton, Moragh; Frith, Vera; Kelly-Laubscher, Roisin; Muna, Natashia; van der Merwe, Mathilde

2017-01-01

Internationally, there has been increasing emphasis on the teaching of the academic literacies, particularly reading and writing, in higher education institutions. However, recent research is highlighting the need for more explicit teaching of multimodal forms of communication, such as the visual literacies, in undergraduate courses in a wide…

Evaluation of Modular EFL Educational Program (Audio-Visual Materials Translation & Translation of Deeds & Documents)

ERIC Educational Resources Information Center

Imani, Sahar Sadat Afshar

2013-01-01

Modular EFL Educational Program has managed to offer specialized language education in two specific fields: Audio-visual Materials Translation and Translation of Deeds and Documents. However, no explicit empirical studies can be traced on both internal and external validity measures as well as the extent of compatibility of both courses with the…

Is Visually Guided Reaching in Early Infancy a Myth?

ERIC Educational Resources Information Center

Clifton, Rachel K.; And Others

1993-01-01

Seven infants were tested between the ages of 6 and 25 weeks to see how they would grasp objects presented in full light and glowing or sounding objects presented in total darkness. In all three conditions, the infants first grasped the objects at nearly the same time, suggesting that internal stimuli, not visual guidance, directed their actions.…

International Halley watch amateur observers' manual for scientific comet studies. Part 1: Methods

NASA Technical Reports Server (NTRS)

Edberg, S. J.

1983-01-01

The International Halley Watch is described as well as comets and observing techniques. Information on periodic Comet Halley's apparition for its 1986 perihelion passage is provided. Instructions are given for observation projects valuable to the International Halley Watch in six areas of study: (1) visual observations; (2) photography; (3) astrometry; (4) spectroscopic observations; (5) photoelectric photometry; and (6) meteor observations.

The BEVPS: A new test battery to assess visual perceptual and spatial processing abilities in 5-14 year-old children.

PubMed

Schmetz, Emilie; Rousselle, Laurence; Ballaz, Cécile; Detraux, Jean-Jacques; Barisnikov, Koviljka

2017-06-20

This study aims to examine the different levels of visual perceptual object recognition (early, intermediate, and late) defined in Humphreys and Riddoch's model as well as basic visual spatial processing in children using a new test battery (BEVPS). It focuses on the age sensitivity, internal coherence, theoretical validity, and convergent validity of this battery. French-speaking, typically developing children (n = 179; 5 to 14 years) were assessed using 15 new computerized subtests. After selecting the most age-sensitive tasks though ceiling effect and correlation analyses, an exploratory factorial analysis was run with the 12 remaining subtests to examine the BEVPS' theoretical validity. Three separate factors were identified for the assessment of the stimuli's basic features (F1, four subtests), view-dependent and -independent object representations (F2, six subtests), and basic visual spatial processing (F3, two subtests). Convergent validity analyses revealed positive correlations between F1 and F2 and the Beery-VMI visual perception subtest, while no such correlations were found for F3. Children's performances progressed until the age of 9-10 years in F1 and in view-independent representations (F2), and until 11-12 years in view-dependent representations (F2). However, no progression with age was observed in F3. Moreover, the selected subtests, present good-to-excellent internal consistency, which indicates that they provide reliable measures for the assessment of visual perceptual processing abilities in children.

Compression and reflection of visually evoked cortical waves

PubMed Central

Xu, Weifeng; Huang, Xiaoying; Takagaki, Kentaroh; Wu, Jian-young

2007-01-01

Summary Neuronal interactions between primary and secondary visual cortical areas are important for visual processing, but the spatiotemporal patterns of the interaction are not well understood. We used voltage-sensitive dye imaging to visualize neuronal activity in rat visual cortex and found novel visually evoked waves propagating from V1 to other visual areas. A primary wave originated in the monocular area of V1 and was “compressed” when propagating to V2. A reflected wave initiated after compression and propagated backward into V1. The compression occurred at the V1/V2 border, and local GABAA inhibition is important for the compression. The compression/reflection pattern provides a two-phase modulation: V1 is first depolarized by the primary wave and then V1 and V2 are simultaneously depolarized by the reflected and primary waves, respectively. The compression/reflection pattern only occurred for evoked but not for spontaneous waves, suggesting that it is organized by an internal mechanism associated with visual processing. PMID:17610821

Is digital photography an accurate and precise method for measuring range of motion of the shoulder and elbow?

PubMed

Russo, Russell R; Burn, Matthew B; Ismaily, Sabir K; Gerrie, Brayden J; Han, Shuyang; Alexander, Jerry; Lenherr, Christopher; Noble, Philip C; Harris, Joshua D; McCulloch, Patrick C

2018-03-01

Accurate measurements of shoulder and elbow motion are required for the management of musculoskeletal pathology. The purpose of this investigation was to compare three techniques for measuring motion. The authors hypothesized that digital photography would be equivalent in accuracy and show higher precision compared to the other two techniques. Using infrared motion capture analysis as the reference standard, shoulder flexion/abduction/internal rotation/external rotation and elbow flexion/extension were measured using visual estimation, goniometry, and digital photography on 10 fresh frozen cadavers. These measurements were performed by three physical therapists and three orthopaedic surgeons. Accuracy was defined by the difference from the reference standard (motion capture analysis), while precision was defined by the proportion of measurements within the authors' definition of clinical significance (10° for all motions except for elbow extension where 5° was used). Analysis of variance (ANOVA), t-tests, and chi-squared tests were used. Although statistically significant differences were found in measurement accuracy between the three techniques, none of these differences met the authors' definition of clinical significance. Precision of the measurements was significantly higher for both digital photography (shoulder abduction [93% vs. 74%, p < 0.001], shoulder internal rotation [97% vs. 83%, p = 0.001], and elbow flexion [93% vs. 65%, p < 0.001]) and goniometry (shoulder abduction [92% vs. 74%, p < 0.001] and shoulder internal rotation [94% vs. 83%, p = 0.008]) than visual estimation. Digital photography was more precise than goniometry for measurements of elbow flexion only [93% vs. 76%, p < 0.001]. There was no clinically significant difference in measurement accuracy between the three techniques for shoulder and elbow motion. Digital photography showed higher measurement precision compared to visual estimation for shoulder abduction, shoulder internal rotation, and elbow flexion. However, digital photography was only more precise than goniometry for measurements of elbow flexion. Overall digital photography shows equivalent accuracy to visual estimation and goniometry, but with higher precision than visual estimation. Copyright © 2017. Published by Elsevier B.V.

From Vesalius to virtual reality: How embodied cognition facilitates the visualization of anatomy

NASA Astrophysics Data System (ADS)

Jang, Susan

This study examines the facilitative effects of embodiment of a complex internal anatomical structure through three-dimensional ("3-D") interactivity in a virtual reality ("VR") program. Since Shepard and Metzler's influential 1971 study, it has been known that 3-D objects (e.g., multiple-armed cube or external body parts) are visually and motorically embodied in our minds. For example, people take longer to rotate mentally an image of their hand not only when there is a greater degree of rotation, but also when the images are presented in a manner incompatible with their natural body movement (Parsons, 1987a, 1994; Cooper & Shepard, 1975; Sekiyama, 1983). Such findings confirm the notion that our mental images and rotations of those images are in fact confined by the laws of physics and biomechanics, because we perceive, think and reason in an embodied fashion. With the advancement of new technologies, virtual reality programs for medical education now enable users to interact directly in a 3-D environment with internal anatomical structures. Given that such structures are not readily viewable to users and thus not previously susceptible to embodiment, coupled with the VR environment also affording all possible degrees of rotation, how people learn from these programs raises new questions. If we embody external anatomical parts we can see, such as our hands and feet, can we embody internal anatomical parts we cannot see? Does manipulating the anatomical part in virtual space facilitate the user's embodiment of that structure and therefore the ability to visualize the structure mentally? Medical students grouped in yoked-pairs were tasked with mastering the spatial configuration of an internal anatomical structure; only one group was allowed to manipulate the images of this anatomical structure in a 3-D VR environment, whereas the other group could only view the manipulation. The manipulation group outperformed the visual group, suggesting that the interactivity that took place among the manipulation group promoted visual and motoric embodiment, which in turn enhanced learning. Moreover, when accounting for spatial ability, it was found that manipulation benefits students with low spatial ability more than students with high spatial ability.

Analyzing Internal Fragmentation of Electrosprayed Ubiquitin Ions During Beam-Type Collisional Dissociation

NASA Astrophysics Data System (ADS)

Durbin, Kenneth R.; Skinner, Owen S.; Fellers, Ryan T.; Kelleher, Neil L.

2015-05-01

Gaseous fragmentation of intact proteins is multifaceted and can be unpredictable by current theories in the field. Contributing to the complexity is the multitude of precursor ion states and fragmentation channels. Terminal fragment ions can be re-fragmented, yielding product ions containing neither terminus, termed internal fragment ions. In an effort to better understand and capitalize upon this fragmentation process, we collisionally dissociated the high (13+), middle (10+), and low (7+) charge states of electrosprayed ubiquitin ions. Both terminal and internal fragmentation processes were quantified through step-wise increases of voltage potential in the collision cell. An isotope fitting algorithm matched observed product ions to theoretical terminal and internal fragment ions. At optimal energies for internal fragmentation of the 10+, nearly 200 internal fragments were observed; on average each of the 76 residues in ubiquitin was covered by 24.1 internal fragments. A pertinent finding was that formation of internal ions occurs at similar energy thresholds as terminal b- and y-ion types in beam-type activation. This large amount of internal fragmentation is frequently overlooked during top-down mass spectrometry. As such, we present several new approaches to visualize internal fragments through modified graphical fragment maps. With the presented advances of internal fragment ion accounting and visualization, the total percentage of matched fragment ions increased from approximately 40% to over 75% in a typical beam-type MS/MS spectrum. These sequence coverage improvements offer greater characterization potential for whole proteins with no needed experimental changes and could be of large benefit for future high-throughput intact protein analysis.

Hazard report. Internal wire breakage in reusable electrosurgical active electrode cables may cause sparking and surgical fires.

PubMed

2009-07-01

Breaks in the internal wires of reusable electrosurgical active electrode cables can increase the risk of injuries and surgical fires. Careful visual and manual inspection during reprocessing and immediately before use, coupled with periodic replacement, can help limit the risk.

A Visual Language for World Marketing.

ERIC Educational Resources Information Center

Vanden Bergh, Bruce G.; Sentell, Gerald D.

A practical solution to many of the communication obstacles found in international markets can be found in the development and widespread adoption of a standardized system of international graphic symbols. Any plan to develop and implement a truly acceptable and universal system of graphic symbols will have to overcome many obstacles that past…

Endocytosis and interaction of poly (amidoamine) dendrimers with Caco-2 cells.

PubMed

Kitchens, Kelly M; Foraker, Amy B; Kolhatkar, Rohit B; Swaan, Peter W; Ghandehari, Hamidreza

2007-11-01

To investigate the internalization and subcellular trafficking of fluorescently labeled poly (amidoamine) (PAMAM) dendrimers in intestinal cell monolayers. PAMAM dendrimers with positive or negative surface charge were conjugated to fluorescein isothiocyanate (FITC) and visualized for colocalization with endocytosis markers using confocal microscopy. Effect of concentration, generation and charge on the morphology of microvilli was observed using transmission electron microscopy. Both cationic and anionic PAMAM dendrimers internalized within 20 min, and differentially colocalized with endocytosis markers clathrin, EEA-1, and LAMP-1. Transmission electron microscopy analysis showed a concentration-, generation- and surface charge-dependent effect on microvilli morphology. These studies provide visual evidence that endocytic mechanism(s) contribute to the internalization and subcellular trafficking of PAMAM dendrimers across the intestinal cells, and that appropriate selection of PAMAM dendrimers based on surface charge, concentration and generation number allows the application of these polymers for oral drug delivery.

Visual Times of Maxima for Short Period Pulsating Stars III

NASA Astrophysics Data System (ADS)

Samolyk, G.

2018-06-01

Abstract This compilation contains 524 times of maxima of 9 short period pulsating stars (primarily RR Lyrae stars; RW Cnc, TT Cnc, VZ Cnc, RR Cet, XZ Cyg, DM Cyg, RW Dra, XZ Dra, RR Gem). These were reduced from a portion of the visual observations made from 1966 to 2014 that are included in the AAVSO International Database.

The Avian Knowledge Network : A partnership to organize, analyze, and visualize bird observation data for education, conservation, research, and land management

Treesearch

Marshall Iliff; Leo Salas; Ernesto Ruelas Inzunza; Grant Ballard; Denis Lepage; Steve Kelling

2009-01-01

The Avian Knowledge Network (AKN) is an international collaboration of academic, nongovernment, and government institutions with the goal of organizing observations of birds into an interoperable format to enhance access, data visualization and exploration, and scientifi c analyses. The AKN uses proven cyberinfrastructure and informatics techniques as the foundation of...

Visual Display Study: National 4-H Center. A 4-H Intern Report.

ERIC Educational Resources Information Center

Farwell, Sanford W.

An internship report cites ways in which the National 4-H Center could be more effective in a visual sense. The author suggests collecting the memorabilia already at the Center to form an historical museum and coordinating the historical items with present items. Impact areas, those with a lot of traffic, are discussed individually in terms of…

Visual Culture Learning Communities: How and What Students Come to Know in Informal Art Groups

ERIC Educational Resources Information Center

Freedman, Kerry; Heijnen, Emiel; Kallio-Tavin, Mira; Karpati, Andrea; Papp, Laszlo

2013-01-01

This article is the report of a large-scale, international research project involving focus group interviews of adolescent and young adult members of a variety of self-initiated visual culture groups in five urban areas (Amsterdam, Budapest, Chicago, Helsinki, and Hong Kong). Each group was established by young people around their interests in the…

Equilibrium relations and bipolar cognitive mapping for online analytical processing with applications in international relations and strategic decision support.

PubMed

Zhang, Wen-Ran

2003-01-01

Bipolar logic, bipolar sets, and equilibrium relations are proposed for bipolar cognitive mapping and visualization in online analytical processing (OLAP) and online analytical mining (OLAM). As cognitive models, cognitive maps (CMs) hold great potential for clustering and visualization. Due to the lack of a formal mathematical basis, however, CM-based OLAP and OLAM have not gained popularity. Compared with existing approaches, bipolar cognitive mapping has a number of advantages. First, bipolar CMs are formal logical models as well as cognitive models. Second, equilibrium relations (with polarized reflexivity, symmetry, and transitivity), as bipolar generalizations and fusions of equivalence relations, provide a theoretical basis for bipolar visualization and coordination. Third, an equilibrium relation or CM induces bipolar partitions that distinguish disjoint coalition subsets not involved in any conflict, disjoint coalition subsets involved in a conflict, disjoint conflict subsets, and disjoint harmony subsets. Finally, equilibrium energy analysis leads to harmony and stability measures for strategic decision and multiagent coordination. Thus, this work bridges a gap for CM-based clustering and visualization in OLAP and OLAM. Basic ideas are illustrated with example CMs in international relations.

ILM peeling in nontractional diabetic macular edema: review and metanalysis.

PubMed

Rinaldi, M; dell'Omo, R; Morescalchi, F; Semeraro, F; Gambicorti, E; Cacciatore, F; Chiosi, F; Costagliola, C

2017-10-31

To evaluate the effect of internal limiting membrane (ILM) peeling during vitrectomy for nontractional diabetic macular edema. PUBMED, MEDLINE and CENTRAL were reviewed using the following terms (or combination of terms): diabetic macular edema, nontractional diabetic macular edema, internal limiting membrane peeling, vitrectomy, Müller cells. Randomized and nonrandomized studies were included. The eligible studies compared anatomical and functional outcomes of vitrectomy with or without ILM peeling for tractional and nontractional diabetic macular edema. Postoperative best-corrected visual acuity and central macular thickness were considered, respectively, the primary and secondary outcomes. Meta-analysis on mean differences between vitrectomy with and without ILM peeling was performed using inverse variance method in random effects. Four studies with 672 patients were eligible for analysis. No significant difference was found between postoperative best-corrected visual acuity or best-corrected visual acuity change of ILM peeling group compared with nonpeeling group. There was no significant difference in postoperative central macular thickness and central macular thickness reduction between the two groups. The visual acuity outcomes in patients affected by nontractional diabetic macular edema using pars plana vitrectomy with ILM peeling versus no ILM peeling were not significantly different. A larger prospective and randomized study would be necessary.

Internal and External Imagery Effects on Tennis Skills Among Novices.

PubMed

Dana, Amir; Gozalzadeh, Elmira

2017-10-01

The purpose of this study was to determine the effects of internal and external visual imagery perspectives on performance accuracy of open and closed tennis skills (i.e., serve, forehand, and backhand) among novices. Thirty-six young male novices, aged 15-18 years, from a summer tennis program participated. Following initial skill acquisition (12 sessions), baseline assessments of imagery ability and imagery perspective preference were used to assign participants to one of three groups: internal imagery ( n = 12), external imagery ( n = 12), or a no-imagery (mental math exercise) control group ( n = 12). The experimental interventions of 15 minutes of mental imagery (internal or external) or mental math exercises followed by 15 minutes of physical practice were held three times a week for six weeks. The performance accuracy of the groups on the serve, forehand, and backhand strokes was measured at pre- and post-test using videotaping. Results showed significant increases in the performance accuracy of all three tennis strokes in all three groups, but serve accuracy in the internal imagery group and forehand accuracy in the external imagery group showed greater improvements, while backhand accuracy was similarly improved in all three groups. These findings highlight differential efficacy of internal and external visual imagery for performance improvement on complex sport skills in early stage motor learning.

Virtual Environments in Scientific Visualization

NASA Technical Reports Server (NTRS)

Bryson, Steve; Lisinski, T. A. (Technical Monitor)

1994-01-01

Virtual environment technology is a new way of approaching the interface between computers and humans. Emphasizing display and user control that conforms to the user's natural ways of perceiving and thinking about space, virtual environment technologies enhance the ability to perceive and interact with computer generated graphic information. This enhancement potentially has a major effect on the field of scientific visualization. Current examples of this technology include the Virtual Windtunnel being developed at NASA Ames Research Center. Other major institutions such as the National Center for Supercomputing Applications and SRI International are also exploring this technology. This talk will be describe several implementations of virtual environments for use in scientific visualization. Examples include the visualization of unsteady fluid flows (the virtual windtunnel), the visualization of geodesics in curved spacetime, surface manipulation, and examples developed at various laboratories.

A Presentation of Spectacular Visualizations

NASA Technical Reports Server (NTRS)

Hasler, Fritz; Einaudi, Franco (Technical Monitor)

2000-01-01

The NASA/NOAA/AMS Earth Science Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to Florida and the KSC Visitor's Center. Go back to the early weather satellite images from the 1960s see them contrasted with the latest International global satellite weather movies including killer hurricanes and tornadic thunderstorms. See the latest spectacular images from NASA and the National Oceanic and Atmospheric Administration (NOAA) remote sensing missions like the Geostationary Operational Environmental Satellites (GOES), NOAA, Tropical Rainfall Measuring Mission (TRMM), SeaWiFS, Landsat7, and new Terra which will be visualized with state-of-the art tools. Shown in High Definition TV resolution (2048 x 768 pixels) are visualizations of hurricanes Lenny, Floyd, Georges, Mitch, Fran, and Linda. See visualizations featured on covers of magazines like Newsweek, TIME, National Geographic, Popular Science, and on National and International Network TV. New Digital Earth visualization tools allow us to roam and zoom through massive global images including a Landsat tour of the US, with drill-downs into major cities using one meter resolution spy-satellite technology from the Space Imaging IKONOS satellite. Spectacular new visualizations of the global atmosphere and oceans are shown. See massive dust storms sweeping across Africa. See ocean vortexes and currents that bring up the nutrients to feed tiny plankton and draw the fish, giant whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. The demonstration is interactively driven by a SGI Octane Graphics Supercomputer with dual CPUs, 5 Gigabytes of RAM and Terabyte disk using two projectors across the super sized Universe Theater panoramic screen.

Contrast-enhanced ultrasonography vs B-mode ultrasound for visualization of intima-media thickness and detection of plaques in human carotid arteries.

PubMed

Shah, Benoy N; Chahal, Navtej S; Kooner, Jaspal S; Senior, Roxy

2017-05-01

Carotid intima-media thickness (IMT) and plaque are recognized markers of increased risk for cerebrovascular events. Accurate visualization of the IMT and plaques is dependent upon image quality. Ultrasound contrast agents improve image quality during echocardiography-this study assessed whether contrast-enhanced ultrasound (CEUS) improves carotid IMT visualization and plaque detection in an asymptomatic population. Individuals free from known cardiovascular disease, enrolled in a community study, underwent B-mode and CEUS carotid imaging. Each carotid artery was divided into 10 segments (far and near walls of the proximal, mid and distal segments of the common carotid artery, the carotid bulb, and internal carotid artery). Visualization of the IMT complex and plaque assessments was made during both B-mode and CEUS imaging for all enrolled subjects, a total of 175 individuals (mean age 65±9 years). Visualization of the IMT was significantly improved during CEUS compared with B-mode imaging, in both near and far walls of the carotid arteries (% IMT visualization during B-mode vs CEUS imaging: 61% vs 94% and 66% vs 95% for right and left carotid arteries, respectively, P<.001 for both). Additionally, a greater number of plaques were detected during CEUS imaging compared with B-mode imaging (367 plaques vs 350 plaques, P=.02). Contrast-enhanced ultrasound improves visualization of the intima-media complex, in both near and far walls, of the common and internal carotid arteries and permits greater detection of carotid plaques. Further studies are required to determine whether there is incremental clinical and prognostic benefit related to superior plaque detection by CEUS. © 2017, Wiley Periodicals, Inc.

Clinical study on evaluation of anti-cataract effect of Triphaladi Ghana Vati and Elaneer Kuzhambu Anjana in Timira (immature cataract).

PubMed

Bhati, Hitesh; Manjusha, R

2015-01-01

Senile cataract is the leading cause of blindness according to the World Health Report, 1998. Till date no accepted medical treatment is available for cataract. In Ayurveda visual disturbances are described in the context of Timira, Kacha and Linganasha. Timira is an early stage characterized by blurring of vision and Linganasha is end stage where complete loss of vision occurs. Ancient scholars have advocated different Anjana application and oral medications in the Timira and Kacha stage. To study the efficacy of test drugs Triphaladi Ghana Vati and Elaneer Kuzhambu Anjana in immature cataract. In this trial patients having Senile Immature Cataract were randomized with equal probability to one of the two treatment Groups A and B (n = 20 each). In Group A Triphaladi Ghana Vati 500 mg internally for 3 months and in Group B Triphaladi Ghana Vati 500 mg internally and Elaneer Kuzhambu Anjana for local application were given. Assessment was done on the basis of blurring of vision, visualization of nonexisting things, difficulty in bright light and dim light or night vision, distant visual acuity, pinhole vision, best corrected visual acuity and cataract grading on slit lamp. Both groups showed statistically significant changes in blurring of vision, difficulty in glare, daytime and bright light, distant visual activity, pinhole vision, and best-corrected visual acuity. Group B also showed significant changes in difficulty in night time, visualization of nonexisting things and in nuclear cataract. The study establishes that test drugs can reduce and control the progress of immature cataract, and combined therapy was found more effective. Chakshushya Rasayana, early diagnosis and proper management on Doshic lines can prevent arrest or delay senile cataract.

Clinical study on evaluation of anti-cataract effect of Triphaladi Ghana Vati and Elaneer Kuzhambu Anjana in Timira (immature cataract)

PubMed Central

Bhati, Hitesh; Manjusha, R.

2015-01-01

Introduction: Senile cataract is the leading cause of blindness according to the World Health Report, 1998. Till date no accepted medical treatment is available for cataract. In Ayurveda visual disturbances are described in the context of Timira, Kacha and Linganasha. Timira is an early stage characterized by blurring of vision and Linganasha is end stage where complete loss of vision occurs. Ancient scholars have advocated different Anjana application and oral medications in the Timira and Kacha stage. Aim: To study the efficacy of test drugs Triphaladi Ghana Vati and Elaneer Kuzhambu Anjana in immature cataract. Materials and Methods: In this trial patients having Senile Immature Cataract were randomized with equal probability to one of the two treatment Groups A and B (n = 20 each). In Group A Triphaladi Ghana Vati 500 mg internally for 3 months and in Group B Triphaladi Ghana Vati 500 mg internally and Elaneer Kuzhambu Anjana for local application were given. Assessment was done on the basis of blurring of vision, visualization of nonexisting things, difficulty in bright light and dim light or night vision, distant visual acuity, pinhole vision, best corrected visual acuity and cataract grading on slit lamp. Results: Both groups showed statistically significant changes in blurring of vision, difficulty in glare, daytime and bright light, distant visual activity, pinhole vision, and best-corrected visual acuity. Group B also showed significant changes in difficulty in night time, visualization of nonexisting things and in nuclear cataract. Conclusion: The study establishes that test drugs can reduce and control the progress of immature cataract, and combined therapy was found more effective. Chakshushya Rasayana, early diagnosis and proper management on Doshic lines can prevent arrest or delay senile cataract. PMID:27313415

The internal model: A study of the relative contribution of proprioception and visual information to failure detection in dynamic systems. [sensitivity of operators versus monitors to failures

NASA Technical Reports Server (NTRS)

Kessel, C.; Wickens, C. D.

1978-01-01

The development of the internal model as it pertains to the detection of step changes in the order of control dynamics is investigated for two modes of participation: whether the subjects are actively controlling those dynamics or are monitoring an autopilot controlling them. A transfer of training design was used to evaluate the relative contribution of proprioception and visual information to the overall accuracy of the internal model. Sixteen subjects either tracked or monitored the system dynamics as a 2-dimensional pursuit display under single task conditions and concurrently with a sub-critical tracking task at two difficulty levels. Detection performance was faster and more accurate in the manual as opposed to the autopilot mode. The concurrent tracking task produced a decrement in detection performance for all conditions though this was more marked for the manual mode. The development of an internal model in the manual mode transferred positively to the automatic mode producing enhanced detection performance. There was no transfer from the internal model developed in the automatic mode to the manual mode.

Influence of Internal and External Noise on Spontaneous Visuomotor Synchronization.

PubMed

Varlet, Manuel; Schmidt, R C; Richardson, Michael J

2016-01-01

Historically, movement noise or variability is considered to be an undesirable property of biological motor systems. In particular, noise is typically assumed to degrade the emergence and stability of rhythmic motor synchronization. Recently, however, it has been suggested that small levels of noise might actually improve the functioning of motor systems and facilitate their adaptation to environmental events. Here, the authors investigated whether noise can facilitate spontaneous rhythmic visuomotor synchronization. They examined the influence of internal noise in the rhythmic limb movements of participants and external noise in the movement of an oscillating visual stimulus on the occurrence of spontaneous synchronization. By indexing the natural frequency variability of participants and manipulating the frequency variability of the visual stimulus, the authors demonstrated that both internal and external noise degrade synchronization when the participants' and stimulus movement frequencies are similar, but can actually facilitate synchronization when the frequencies are different. Furthermore, the two kinds of noise interact with each other. Internal noise facilitates synchronization only when external noise is minimal and vice versa. Too much internal and external noise together degrades synchronization. These findings open new perspectives for better understanding the role of noise in human rhythmic coordination.

Internal attention to features in visual short-term memory guides object learning

PubMed Central

Fan, Judith E.; Turk-Browne, Nicholas B.

2013-01-01

Attending to objects in the world affects how we perceive and remember them. What are the consequences of attending to an object in mind? In particular, how does reporting the features of a recently seen object guide visual learning? In three experiments, observers were presented with abstract shapes in a particular color, orientation, and location. After viewing each object, observers were cued to report one feature from visual short-term memory (VSTM). In a subsequent test, observers were cued to report features of the same objects from visual long-term memory (VLTM). We tested whether reporting a feature from VSTM: (1) enhances VLTM for just that feature (practice-benefit hypothesis), (2) enhances VLTM for all features (object-based hypothesis), or (3) simultaneously enhances VLTM for that feature and suppresses VLTM for unreported features (feature-competition hypothesis). The results provided support for the feature-competition hypothesis, whereby the representation of an object in VLTM was biased towards features reported from VSTM and away from unreported features (Experiment 1). This bias could not be explained by the amount of sensory exposure or response learning (Experiment 2) and was amplified by the reporting of multiple features (Experiment 3). Taken together, these results suggest that selective internal attention induces competitive dynamics among features during visual learning, flexibly tuning object representations to align with prior mnemonic goals. PMID:23954925

EFFECT OF INTERNAL LIMITING MEMBRANE PEELING DURING VITRECTOMY FOR DIABETIC MACULAR EDEMA: Systematic Review and Meta-analysis.

PubMed

Nakajima, Takuya; Roggia, Murilo F; Noda, Yasuo; Ueta, Takashi

2015-09-01

To evaluate the effect of internal limiting membrane (ILM) peeling during vitrectomy for diabetic macular edema. MEDLINE, EMBASE, and CENTRAL were systematically reviewed. Eligible studies included randomized or nonrandomized studies that compared surgical outcomes of vitrectomy with or without ILM peeling for diabetic macular edema. The primary and secondary outcome measures were postoperative best-corrected visual acuity and central macular thickness. Meta-analysis on mean differences between vitrectomy with and without ILM peeling was performed using inverse variance method in random effects. Five studies (7 articles) with 741 patients were eligible for analysis. Superiority (95% confidence interval) in postoperative best-corrected visual acuity in ILM peeling group compared with nonpeeling group was 0.04 (-0.05 to 0.13) logMAR (equivalent to 2.0 ETDRS letters, P = 0.37), and superiority in best-corrected visual acuity change in ILM peeling group was 0.04 (-0.02 to 0.09) logMAR (equivalent to 2.0 ETDRS letters, P = 0.16). There was no significant difference in postoperative central macular thickness and central macular thickness reduction between the two groups. The visual acuity outcomes using pars plana vitrectomy with ILM peeling versus no ILM peeling were not significantly different. A larger randomized prospective study would be necessary to adequately address the effectiveness of ILM peeling on visual acuity outcomes.

Internal attention to features in visual short-term memory guides object learning.

PubMed

Fan, Judith E; Turk-Browne, Nicholas B

2013-11-01

Attending to objects in the world affects how we perceive and remember them. What are the consequences of attending to an object in mind? In particular, how does reporting the features of a recently seen object guide visual learning? In three experiments, observers were presented with abstract shapes in a particular color, orientation, and location. After viewing each object, observers were cued to report one feature from visual short-term memory (VSTM). In a subsequent test, observers were cued to report features of the same objects from visual long-term memory (VLTM). We tested whether reporting a feature from VSTM: (1) enhances VLTM for just that feature (practice-benefit hypothesis), (2) enhances VLTM for all features (object-based hypothesis), or (3) simultaneously enhances VLTM for that feature and suppresses VLTM for unreported features (feature-competition hypothesis). The results provided support for the feature-competition hypothesis, whereby the representation of an object in VLTM was biased towards features reported from VSTM and away from unreported features (Experiment 1). This bias could not be explained by the amount of sensory exposure or response learning (Experiment 2) and was amplified by the reporting of multiple features (Experiment 3). Taken together, these results suggest that selective internal attention induces competitive dynamics among features during visual learning, flexibly tuning object representations to align with prior mnemonic goals. Copyright © 2013 Elsevier B.V. All rights reserved.

Test of Gross Motor Development-3 (TGMD-3) with the Use of Visual Supports for Children with Autism Spectrum Disorder: Validity and Reliability.

PubMed

Allen, K A; Bredero, B; Van Damme, T; Ulrich, D A; Simons, J

2017-03-01

The validity and reliability of the Test of Gross Motor Development-3 (TGMD-3) were measured, taking into consideration the preference for visual learning of children with autism spectrum disorder (ASD). The TGMD-3 was administered to 14 children with ASD (4-10 years) and 21 age-matched typically developing children under two conditions: TGMD-3 traditional protocol, and TGMD-3 visual support protocol. Excellent levels of internal consistency, test-retest, interrater and intrarater reliability were achieved for the TGMD-3 visual support protocol. TGMD-3 raw scores of children with ASD were significantly lower than typically developing peers, however, significantly improved using the TGMD-3 visual support protocol. This demonstrates that the TGMD-3 visual support protocol is a valid and reliable assessment of gross motor performance for children with ASD.

[Challenges in Traffic for Blind and Visually Impaired People and Strategies for their Safe Participation].

PubMed

Högner, N

2015-08-01

Blind and visually impaired people experience special risks and hazards in road traffic. This refers to participation as a driver, bicycle rider and pedestrian. These risks are shown by a review of international research studies and a study by the author, where 45 people with Usher syndrome were asked about their accident rates and causes as driver, bicycle rider and pedestrian. In addition, basic legal information has been worked out to demonstrate the visual conditions of people with visual impairment for participation in road traffic. The research studies show that blind and visually impaired persons are particularly exposed to experience high risks in traffic. These risks can be reduced through acquisition of skills and coping strategies such as training in orientation and mobility. People with visual impairment need special programmes which help to reduce traffic hazards. Georg Thieme Verlag KG Stuttgart · New York.

Role of the posterior parietal cortex in updating reaching movements to a visual target.

PubMed

Desmurget, M; Epstein, C M; Turner, R S; Prablanc, C; Alexander, G E; Grafton, S T

1999-06-01

The exact role of posterior parietal cortex (PPC) in visually directed reaching is unknown. We propose that, by building an internal representation of instantaneous hand location, PPC computes a dynamic motor error used by motor centers to correct the ongoing trajectory. With unseen right hands, five subjects pointed to visual targets that either remained stationary or moved during saccadic eye movements. Transcranial magnetic stimulation (TMS) was applied over the left PPC during target presentation. Stimulation disrupted path corrections that normally occur in response to target jumps, but had no effect on those directed at stationary targets. Furthermore, left-hand movement corrections were not blocked, ruling out visual or oculomotor effects of stimulation.

Visualizando el desarrollo de la nanomedicina en México.

PubMed

Robles-Belmont, Eduardo; Gortari-Rabiela, Rebeca de; Galarza-Barrios, Pilar; Siqueiros-García, Jesús Mario; Ruiz-León, Alejandro Arnulfo

2017-01-01

In this article we present a set of different visualizations of Mexico's nanomedicine scientific production data. Visualizations were developed using different methodologies for data analysis and visualization such as social network analysis, geography of science maps, and complex network communities analysis. Results are a multi-dimensional overview of the evolution of nanomedicine in Mexico. Moreover, visualizations allowed to identify trends and patterns of collaboration at the national and international level. Trends are also found in the knowledge structure of themes and disciplines. Finally, we identified the scientific communities in Mexico that are responsible for the new knowledge production in this emergent field of science. Copyright: © 2017 SecretarÍa de Salud

Compensation of Corneal Oblique Astigmatism by Internal Optics: a Theoretical Analysis

PubMed Central

Liu, Tao; Thibos, Larry N.

2017-01-01

Purpose Oblique astigmatism is a prominent optical aberration of peripheral vision caused by oblique incidence of rays striking the refracting surfaces of the cornea and crystalline lens. We inquired whether oblique astigmatism from these two sources should be expected, theoretically, to have the same or opposite signs across the visual field at various states of accommodation. Methods Oblique astigmatism was computed across the central visual field for a rotationally-symmetric schematic-eye using optical design software. Accommodative state was varied by altering the apical radius of curvature and separation of the biconvex lens’s two aspheric surfaces in a manner consistent with published biometry. Oblique astigmatism was evaluated separately for the whole eye, the cornea, and the isolated lens over a wide range of surface curvatures and asphericity values associated with the accommodating lens. We also computed internal oblique astigmatism by subtracting corneal oblique astigmatism from whole-eye oblique astigmatism. Results A visual field map of oblique astigmatism for the cornea in the Navarro model follows the classic, textbook description of radially-oriented axes everywhere in the field. Despite large changes in surface properties during accommodation, intrinsic astigmatism of the isolated human lens for collimated light is also radially oriented and nearly independent of accommodation both in theory and in real eyes. However, the magnitude of ocular oblique astigmatism is smaller than that of the cornea alone, indicating partial compensation by the internal optics. This implies internal oblique astigmatism (which includes wavefront propagation from the posterior surface of the cornea to the anterior surface of the lens and intrinsic lens astigmatism) must have tangentially-oriented axes. This non-classical pattern of tangential axes for internal astigmatism was traced to the influence of corneal power on the angles of incidence of rays striking the internal lens. Conclusions Partial compensation of corneal astigmatism by internal optics is due mainly to the highly converging nature of wavefronts incident upon the lens resulting from corneal refraction. The degree of compensation is quadratically dependent on eccentricity but is expected to diminish as the eye accommodates. Neutralising the cornea by index-matching defeats internal compensation, revealing classical, radially-oriented oblique astigmatism in the isolated lens. PMID:28281302

A novel visual pipework inspection system

NASA Astrophysics Data System (ADS)

Summan, Rahul; Jackson, William; Dobie, Gordon; MacLeod, Charles; Mineo, Carmelo; West, Graeme; Offin, Douglas; Bolton, Gary; Marshall, Stephen; Lille, Alexandre

2018-04-01

The interior visual inspection of pipelines in the nuclear industry is a safety critical activity conducted during outages to ensure the continued safe and reliable operation of plant. Typically, the video output by a manually deployed probe is viewed by an operator looking to identify and localize surface defects such as corrosion, erosion and pitting. However, it is very challenging to estimate the nature and extent of defects by viewing a large structure through a relatively small field of view. This work describes a new visual inspection system employing photogrammetry using a fisheye camera and a structured light system to map the internal geometry of pipelines by generating a photorealistic, geometrically accurate surface model. The error of the system output was evaluated through comparison to a ground truth laser scan (ATOS GOM Triple Scan) of a nuclear grade split pipe sample (stainless steel 304L, 80mm internal diameter) containing defects representative of the application - the error was found to be submillimeter across the sample.

Functional Analysis of Internal Moving Organs Using Super-Resolution Echography

NASA Astrophysics Data System (ADS)

Masuda, Kohji; Ishihara, Ken; Nagakura, Toshiaki; Tsuda, Takao; Furukawa, Toshiyuki; Maeda, Hajime; Kumagai, Sadatoshi; Kodama, Shinzo

1994-05-01

We have developed super-resolution echography to visualize instantaneous velocity and acceleration of internal organs from time-series echograms recorded by a high-frame-rate echograph. The algorithm for this method involves subtraction of two echograms, dividing the difference by the brightness gradient of the first echogram, and normalization of that result by the time interval between the two echograms. Velocity or acceleration is classified into some suitable colors and superimposed on the original B-mode image. Functional diagnosis of moving organs can be made by visualizing instantaneous velocity. In the case of the heart, hypokinesis can be distinguished from a normal heart by the value and the variation of colored parts representing instantaneous velocity. This can also be applied to the liver to observe pulsatile motion. By visualizing instantaneous acceleration, increase or decrease of velocity can be detected. Throb timing and the location of arrhythmia in a heart can be observed. This method has the possibility of contributing to noninvasive functional and characteristic evaluation.

Multisensory Integration and Internal Models for Sensing Gravity Effects in Primates

PubMed Central

Lacquaniti, Francesco; La Scaleia, Barbara; Maffei, Vincenzo

2014-01-01

Gravity is crucial for spatial perception, postural equilibrium, and movement generation. The vestibular apparatus is the main sensory system involved in monitoring gravity. Hair cells in the vestibular maculae respond to gravitoinertial forces, but they cannot distinguish between linear accelerations and changes of head orientation relative to gravity. The brain deals with this sensory ambiguity (which can cause some lethal airplane accidents) by combining several cues with the otolith signals: angular velocity signals provided by the semicircular canals, proprioceptive signals from muscles and tendons, visceral signals related to gravity, and visual signals. In particular, vision provides both static and dynamic signals about body orientation relative to the vertical, but it poorly discriminates arbitrary accelerations of moving objects. However, we are able to visually detect the specific acceleration of gravity since early infancy. This ability depends on the fact that gravity effects are stored in brain regions which integrate visual, vestibular, and neck proprioceptive signals and combine this information with an internal model of gravity effects. PMID:25061610

Multisensory integration and internal models for sensing gravity effects in primates.

PubMed

Lacquaniti, Francesco; Bosco, Gianfranco; Gravano, Silvio; Indovina, Iole; La Scaleia, Barbara; Maffei, Vincenzo; Zago, Myrka

2014-01-01

Gravity is crucial for spatial perception, postural equilibrium, and movement generation. The vestibular apparatus is the main sensory system involved in monitoring gravity. Hair cells in the vestibular maculae respond to gravitoinertial forces, but they cannot distinguish between linear accelerations and changes of head orientation relative to gravity. The brain deals with this sensory ambiguity (which can cause some lethal airplane accidents) by combining several cues with the otolith signals: angular velocity signals provided by the semicircular canals, proprioceptive signals from muscles and tendons, visceral signals related to gravity, and visual signals. In particular, vision provides both static and dynamic signals about body orientation relative to the vertical, but it poorly discriminates arbitrary accelerations of moving objects. However, we are able to visually detect the specific acceleration of gravity since early infancy. This ability depends on the fact that gravity effects are stored in brain regions which integrate visual, vestibular, and neck proprioceptive signals and combine this information with an internal model of gravity effects.

Microscopic visualization of metabotropic glutamate receptors on the surface of living cells using bifunctional magnetic resonance imaging probes.

PubMed

Mishra, Anurag; Mishra, Ritu; Gottschalk, Sven; Pal, Robert; Sim, Neil; Engelmann, Joern; Goldberg, Martin; Parker, David

2014-02-19

A series of bimodal metabotropic glutamate-receptor targeted MRI contrast agents has been developed and evaluated, based on established competitive metabotropic Glu receptor subtype 5 (mGluR5) antagonists. In order to directly visualize mGluR5 binding of these agents on the surface of live astrocytes, variations in the core structure were made. A set of gadolinium conjugates containing either a cyanine dye or a fluorescein moiety was accordingly prepared, to allow visualization by optical microscopy in cellulo. In each case, surface receptor binding was compromised and cell internalization observed. Another approach, examining the location of a terbium analogue via sensitized emission, also exhibited nonspecific cell uptake in neuronal cell line models. Finally, biotin derivatives of two lead compounds were prepared, and the specificity of binding to the mGluR5 cell surface receptors was demonstrated with the aid of their fluorescently labeled avidin conjugates, using both total internal reflection fluorescence (TIRF) and confocal microscopy.

Minimum visual requirements in different occupations in Finland.

PubMed

Aine, E

1984-01-01

In Finland the employers can individually fix the minimum visual requirements for their personnel in almost every occupation. In transportation, in police and national defence proper eyesight is regarded so important that strict visual requirements for these have been fixed by the Government. The regulations are often more close when accepting the person to the occupation than later on when working. The minimum requirements are mostly stated for visual acuity, colour perception and visual fields. In some occupations the regulations concern also the refractive error of the eyes and possible eye diseases. In aviation the regulations have been stated by the International Civil Aviation Organization ( ICAO ). The minimum visual requirements for a driving license in highway traffic are classed according to the types of motor vehicles. In railways , maritime commerce and national defence the task of the worker determines the specified regulations. The policeman must have a distant visual acuity of 0.5 without eyeglasses in both eyes and nearly normal colour perception when starting the training course.

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_IM_KP_0161

NASA Technical Reports Server (NTRS)

Ocuna, M. H.; Ogilvie, K. W.; Baker, D. N.; Curtis, S. A.; Fairfield, D. H.; Mish, W. H.

2000-01-01

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_KP_0192

NASA Technical Reports Server (NTRS)

Ocuna, M. H.; Ogilvie, K. W.; Baker, D. N.; Curtis, S. A.; Fairfield, D. H.; Mish, W. H.

2001-01-01

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_KP_0139

NASA Technical Reports Server (NTRS)

Ocuna, M. H.; Ogilvie, K. W.; Baker, D. N.; Curtis, S. A.; Fairfield, D. H.; Mish, W. H.

1999-01-01

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_IM_KP_0185

NASA Technical Reports Server (NTRS)

Ocuna, M. H.; Ogilvie, K. W.; Baker, D. N.; Curtis, S. A.; Fairfield, D. H.; Mish, W. H.

2000-01-01

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

Structure from Motion Photogrammetry and Micro X-Ray Computed Tomography 3-D Reconstruction Data Fusion for Non-Destructive Conservation Documentation of Lunar Samples

NASA Technical Reports Server (NTRS)

Beaulieu, K. R.; Blumenfeld, E. H.; Liddle, D. A.; Oshel, E. R.; Evans, C. A.; Zeigler, R. A.; Righter, K.; Hanna, R. D.; Ketcham, R. A.

2017-01-01

Our team is developing a modern, cross-disciplinary approach to documentation and preservation of astromaterials, specifically lunar and meteorite samples stored at the Johnson Space Center (JSC) Lunar Sample Laboratory Facility. Apollo Lunar Sample 60639, collected as part of rake sample 60610 during the 3rd Extra-Vehicular Activity of the Apollo 16 mission in 1972, served as the first NASA-preserved lunar sample to be examined by our team in the development of a novel approach to internal and external sample visualization. Apollo Sample 60639 is classified as a breccia with a glass-coated side and pristine mare basalt and anorthosite clasts. The aim was to accurately register a 3-dimensional Micro X-Ray Computed Tomography (XCT)-derived internal composition data set and a Structure-From-Motion (SFM) Photogrammetry-derived high-fidelity, textured external polygonal model of Apollo Sample 60639. The developed process provided the means for accurate, comprehensive, non-destructive visualization of NASA's heritage lunar samples. The data products, to be ultimately served via an end-user web interface, will allow researchers and the public to interact with the unique heritage samples, providing a platform to "slice through" a photo-realistic rendering of a sample to analyze both its external visual and internal composition simultaneously.

How visualization layout relates to locus of control and other personality factors.

PubMed

Ziemkiewicz, Caroline; Ottley, Alvitta; Crouser, R Jordan; Yauilla, Ashley Rye; Su, Sara L; Ribarsky, William; Chang, Remco

2013-07-01

Existing research suggests that individual personality differences are correlated with a user's speed and accuracy in solving problems with different types of complex visualization systems. We extend this research by isolating factors in personality traits as well as in the visualizations that could have contributed to the observed correlation. We focus on a personality trait known as "locus of control” (LOC), which represents a person's tendency to see themselves as controlled by or in control of external events. To isolate variables of the visualization design, we control extraneous factors such as color, interaction, and labeling. We conduct a user study with four visualizations that gradually shift from a list metaphor to a containment metaphor and compare the participants' speed, accuracy, and preference with their locus of control and other personality factors. Our findings demonstrate that there is indeed a correlation between the two: participants with an internal locus of control perform more poorly with visualizations that employ a containment metaphor, while those with an external locus of control perform well with such visualizations. These results provide evidence for the externalization theory of visualization. Finally, we propose applications of these findings to adaptive visual analytics and visualization evaluation.

Developmental and Behavioral Performance of Internationally Adopted Preschoolers: A Pilot Study

ERIC Educational Resources Information Center

Jacobs, Emma; Miller, Laurie C.; Tirella, Linda G.

2010-01-01

Most international adoptees (IA) have rapid catch-up of the delays common at arrival. However, it is not known whether development at arrival predicts later abilities or school readiness. Therefore, we comprehensively evaluated language, fine motor, visual reception (VR), executive function (EF), attention (ATT), and sensory skills (SS) in IA…

46 CFR 115.645 - Alternative Hull Examination (AHE) Procedure.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) Allow access to all internal areas of the hull for examination, except internal tanks that carry fuel... potable water tanks may be examined visually or by non-destructive testing to the satisfaction of the... the extent of damage or to effect permanent repairs if the assessment or repairs cannot be completed...

46 CFR 115.645 - Alternative Hull Examination (AHE) Procedure.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Allow access to all internal areas of the hull for examination, except internal tanks that carry fuel... potable water tanks may be examined visually or by non-destructive testing to the satisfaction of the... the extent of damage or to effect permanent repairs if the assessment or repairs cannot be completed...

46 CFR 115.645 - Alternative Hull Examination (AHE) Procedure.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) Allow access to all internal areas of the hull for examination, except internal tanks that carry fuel... potable water tanks may be examined visually or by non-destructive testing to the satisfaction of the... the extent of damage or to effect permanent repairs if the assessment or repairs cannot be completed...

46 CFR 115.645 - Alternative Hull Examination (AHE) Procedure.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) Allow access to all internal areas of the hull for examination, except internal tanks that carry fuel... potable water tanks may be examined visually or by non-destructive testing to the satisfaction of the... the extent of damage or to effect permanent repairs if the assessment or repairs cannot be completed...

Visions of Our Planet's Atmosphere, Land & Oceans - ETheater Presentation

NASA Technical Reports Server (NTRS)

Hasler, F.

2000-01-01

The NASA/NOAA/AMS Earth Science Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to Florida and the KSC Visitor's Center. Go back to the early weather satellite images from the 1960s see them contrasted with the latest International global satellite weather movies including killer hurricanes & tornadic thunderstorms. See the latest spectacular images from NASA and NOAA remote sensing missions like GOES, NOAA, TRMM, SeaWiFS, Landsat7, & new Terra which will be visualized with state-of-the art tools. Shown in High Definition TV resolution (2048 x 768 pixels) are visualizations of hurricanes Lenny, Floyd, Georges, Mitch, Fran and Linda. See visualizations featured on covers of ma'gazines like Newsweek, TIME, National Geographic, Popular Science and on National & International Network TV. New Digital Earth visualization tools allow us to roam & zoom through massive global images including a Landsat tour of the US, with drill-downs into major cities using 1 m resolution spy-satellite technology from the Space Imaging IKONOS satellite. Spectacular new visualizations of the global atmosphere & oceans are shown. See massive dust storms sweeping across Africa. See ocean vortexes and currents that bring up the nutrients to feed tiny plankton and draw the fish, giant whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. The demonstration is interactively driven by a SGI Octane Graphics Supercomputer with dual CPUS, 5 Gigabytes of RAM and Terabyte disk using two projectors across the super sized Universe Theater panoramic screen.

Photoreceptor change and visual outcome after idiopathic epiretinal membrane removal with or without additional internal limiting membrane peeling.

PubMed

Ahn, Seong Joon; Ahn, Jeeyun; Woo, Se Joon; Park, Kyu Hyung

2014-01-01

To compare the postoperative photoreceptor status and visual outcome after epiretinal membrane removal with or without additional internal limiting membrane (ILM) peeling. Medical records of 40 eyes from 37 patients undergoing epiretinal membrane removal with residual ILM peeling (additional ILM peeling group) and 69 eyes from 65 patients undergoing epiretinal membrane removal without additional ILM peeling (no additional peeling group) were reviewed. The length of defects in cone outer segment tips, inner segment/outer segment junction, and external limiting membrane line were measured using spectral domain optical coherence tomography images of the fovea before and at 1, 3, 6, and 12 months after the surgery. Cone outer segment tips and inner segment/outer segment junction line defects were most severe at postoperative 1 month and gradually restored at 12 months postoperatively. The cone outer segment tips line defect in the additional ILM peeling group was significantly greater than that in the no additional peeling group at postoperative 1 month (P = 0.006), and best-corrected visual acuity was significantly worse in the former group at the same month (P = 0.001). There was no significant difference in the defect size and best-corrected visual acuity at subsequent visits and recurrence rates between the two groups. Patients who received epiretinal membrane surgery without additional ILM peeling showed better visual and anatomical outcome than those with additional ILM peeling at postoperative 1 month. However, surgical outcomes were comparable between the two groups, thereafter. In terms of visual outcome and photoreceptor integrity, additional ILM peeling may not be an essential procedure.

Visions of Our Planet's Atmosphere, Land and Oceans: Electronic-Theater 2000

NASA Technical Reports Server (NTRS)

Hasler, A. F.

2000-01-01

The NASA/NOAA/AMS Earth Science Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to the Delaware Bay and Philadelphia area. Go back to the early weather satellite images from the 1960s see them contrasted with the latest International global satellite weather movies including killer tropical cyclones & tornadic thunderstorms. See the latest spectacular images from NASA, NOAA & UMETSAT remote sensing missions like GOES, Meteosat, NOAA, TRMM, SeaWiFS, Landsat7, & new Terra which will be visualized with state-of-the art tools. Shown in High Definition TV resolution (2048 x 768 pixels) are visualizations of hurricanes Lenny, Floyd, Georges, Mitch, Fran and Linda. see visualizations featured on covers of magazines like Newsweek, TIME, National Geographic, Popular Science and on National & International Network TV. New Digital Earth visualization tools allow us to roam & zoom through massive global images including Landsat tours of the US, and Africa with drill downs of major global cities using 1 m resolution commercialized spy-satellite technology from the Space Imaging IKONOS satellite. Spectacular new visualizations of the global atmosphere & oceans are shown. See massive dust storms sweeping across Africa. see ocean vortexes and currents that bring up the nutrients to feed tiny plankton and draw the fish, giant whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. The demonstration is interactively driven by a SGI Octane Graphics Supercomputer with dual CPUs, 5 Gigabytes of RAM and Terabyte disk using two projectors across a super sized panoramic screen.

NASA/NOAA/AMS Earth Science Electronic Theatre

NASA Technical Reports Server (NTRS)

Hasler, Fritz; Pierce, Hal; Einaudi, Franco (Technical Monitor)

2001-01-01

The NASA/NOAA/AMS Earth Science Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to Florida and the KSC Visitor's Center. Go back to the early weather satellite images from the 1960s see them contrasted with the latest International global satellite weather movies including killer hurricanes & tornadic thunderstorms. See the latest spectacular images from NASA and NOAA remote sensing missions like GOES, NOAA, TRMM, SeaWiFS, Landsat 7, & new Terra which will be visualized with state-of-the art tools. Shown in High Definition TV resolution (2048 x 768 pixels) are visualizations of hurricanes Lenny, Floyd, Georges, Mitch, Fran and Linda. See visualizations featured on covers of magazines like Newsweek, TIME, National Geographic, Popular Science and on National & International Network TV. New Digital Earth visualization tools allow us to roam & zoom through massive global images including a Landsat tour of the US, with drill-downs into major cities using 1 m resolution spy-satellite technology from the Space Imaging IKONOS satellite, Spectacular new visualizations of the global atmosphere & oceans are shown. See massive dust storms sweeping across Africa. See ocean vortexes and currents that bring up the nutrients to feed tiny plankton and draw the fish, giant whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. The demonstration is interactively driven by a SGI Octane Graphics Supercomputer with dual CPUs, 5 Gigabytes of RAM and Terabyte disk using two projectors across the super sized Universe Theater panoramic screen.

DETRIMENTAL EFFECTS OF ACTIVE INTERNAL LIMITING MEMBRANE PEELING DURING EPIRETINAL MEMBRANE SURGERY: Microperimetric Analysis.

PubMed

Deltour, Jean-Baptiste; Grimbert, Pierre; Masse, Helene; Lebreton, Olivier; Weber, Michel

2017-03-01

The aim of the study was to assess the microperimetric consequences of active internal limiting membrane (ILM) peeling during idiopathic epimacular membrane (IEMM) surgery. This retrospective monocentric study included 32 eyes of 31 consecutive patients who underwent IEMM surgery. Internal limiting membrane integrity was assessed by ILM Blue staining after IEMM removal: peeling was spontaneous (Group S) or active (Group A). Preprocedure and postprocedure (1 and 6 months) examinations were performed using visual acuity determination, spectral domain optical coherence tomography and microperimetry. Twenty-two eyes had an "active ILM peeling" and 10 a "spontaneous ILM peeling." Both groups had comparable and significant improvements in visual acuity 6 months after surgery (+1.82 lines [+9 letters] [Group A] and +1.51 lines [+8 letters] [Group S], P < 0.01) associated with a significant reduction in optical coherence tomography central thickness (-99.9 μm [Group A], P < 0.01 and -62.2 μm [Group S], P = 0.05). Six months after surgery, the microperimetry showed more numerous and deeper microscotomas in the Group A than in the Group S (change in the number of microscotomas: 2.09 vs. -0.10, P = 0.06; change in deficit severity score: 13.18 dB vs. -2 dB, P < 0.01 for Group A and S, respectively). The number of microscotomas and also severity were increased in 63.6% of Group A patients and in only 20% of Group S patients. Microscotomas were most frequently located in IEMM and/or ILM areas. Internal limiting membrane peeling has progressively become generalized in IEMM surgery to reduce recurrences. This additional procedure does not change the postoperative visual acuity but increases the development of deeper microscotomas. The real impact on the quality of vision remains unclear. Active ILM peeling in IEMM surgery may be responsible for visual impairment related to its microtraumatic effects.

Acceptance Presentation and Research Study Summary: Research in Educational Communications and Technology. 1982 Association for Educational Communications and Technology Young Researcher Award, Research and Theory Division.

ERIC Educational Resources Information Center

Canelos, James

An internal cognitive variable--mental imagery representation--was studied using a set of three information-processing strategies under external stimulus visual display conditions for various learning levels. The copy strategy provided verbal and visual dual-coding and required formation of a vivid mental image. The relational strategy combined…

Reliability and Validity of the TGMD-2 in Primary-School-Age Children with Visual Impairments

ERIC Educational Resources Information Center

Houwen, Suzanne; Hartman, Esther; Jonker, Laura; Visscher, Chris

2010-01-01

This study examines the psychometric properties of the Test of Gross Motor Development-2 (TGMD-2) in children with visual impairments (VI). Seventy-five children aged between 6 and 12 years with VI completed the TGMD-2 and the Movement Assessment Battery for Children (Movement ABC). The internal consistency of the TGMD-2 was found to be high…

Effect of head circumference on parameters of pattern reversal visual evoked potential in healthy adults of central India.

PubMed

Kothari, R; Singh, R; Singh, S; Bokariya, P

2012-06-01

Visual evoked response testing has been one of the most exciting clinical tools to be developed from neurophysiologic research in recent years and has provided us with an objective method of identifying abnormalities of the afferent visual pathways. Investigation were carried out to see whether the head circumference influence the pattern reversal visual evoked potential (PRVEP) parameters. The study comprised of pattern reversal visual evoked potential (PRVEP) recordings in 400 eyes of 200 normal subjects. Two hundred fourty eight eyes were males and 152 eyes were from 76 female subjects recruited from the Central Indian population in the age range of 40-79 years. Visual evoked potential (VEP) recordings were performed in accordance to the standardized methodology of International Federation of Clinical Neurophysiology (IFCN) Committee Recommendations and International Society for Clinical Electrophysiology of Vision (ISCEV) Guidelines and montages were kept as per 10-20 International System of EEG Electrode placements. The stimulus configuration in this study consisted of the transient pattern reversal method in which a black and white checker board was generated (full field) and displayed on a VEP Monitor by an electronic pattern regenerator inbuilt in an Evoked Potential Recorder (RMS EMG EP MARK II). VEP latencies, duration and amplitude were measured in all subjects and the data were analyzed. The correlation of all the electrophysiological parameters with head circumference was evaluated by Pearson's correlation co-efficient (r) and its statistical significance was evaluated. The prediction equations for all the VEP parameters with respect to head circumference were derived. We found a positive correlation of P 100 latency and N 155 latency with mean head circumference, while a highly significant negative correlation were noted of P 100 amplitude with head circumference. N 70 latency was significantly correlated with head circumference. P 100 duration showed in negative correlation with head circumference. These findings suggest that VEP latencies, duration and amplitude are influenced by the head circumference of the individual in a sample of healthy subjects and head circumference can be a useful predictor of VEP peak latencies, amplitude and duration.

Internal model of gravity influences configural body processing.

PubMed

Barra, Julien; Senot, Patrice; Auclair, Laurent

2017-01-01

Human bodies are processed by a configural processing mechanism. Evidence supporting this claim is the body inversion effect, in which inversion impairs recognition of bodies more than other objects. Biomechanical configuration, as well as both visual and embodied expertise, has been demonstrated to play an important role in this effect. Nevertheless, the important factor of body inversion effect may also be linked to gravity orientation since gravity is one of the most fundamental constraints of our biology, behavior, and perception on Earth. The visual presentation of an inverted body in a typical body inversion paradigm turns the observed body upside down but also inverts the implicit direction of visual gravity in the scene. The orientation of visual gravity is then in conflict with the direction of actual gravity and may influence configural processing. To test this hypothesis, we dissociated the orientations of the body and of visual gravity by manipulating body posture. In a pretest we showed that it was possible to turn an avatar upside down (inversion relative to retinal coordinates) without inverting the orientation of visual gravity when the avatar stands on his/her hands. We compared the inversion effect in typical conditions (with gravity conflict when the avatar is upside down) to the inversion effect in conditions with no conflict between visual and physical gravity. The results of our experiment revealed that the inversion effect, as measured by both error rate and reaction time, was strongly reduced when there was no gravity conflict. Our results suggest that when an observed body is upside down (inversion relative to participants' retinal coordinates) but the orientation of visual gravity is not, configural processing of bodies might still be possible. In this paper, we discuss the implications of an internal model of gravity in the configural processing of observed bodies. Copyright © 2016 Elsevier B.V. All rights reserved.

The SCEC/UseIT Intern Program: Creating Open-Source Visualization Software Using Diverse Resources

NASA Astrophysics Data System (ADS)

Francoeur, H.; Callaghan, S.; Perry, S.; Jordan, T.

2004-12-01

The Southern California Earthquake Center undergraduate IT intern program (SCEC UseIT) conducts IT research to benefit collaborative earth science research. Through this program, interns have developed real-time, interactive, 3D visualization software using open-source tools. Dubbed LA3D, a distribution of this software is now in use by the seismic community. LA3D enables the user to interactively view Southern California datasets and models of importance to earthquake scientists, such as faults, earthquakes, fault blocks, digital elevation models, and seismic hazard maps. LA3D is now being extended to support visualizations anywhere on the planet. The new software, called SCEC-VIDEO (Virtual Interactive Display of Earth Objects), makes use of a modular, plugin-based software architecture which supports easy development and integration of new data sets. Currently SCEC-VIDEO is in beta testing, with a full open-source release slated for the future. Both LA3D and SCEC-VIDEO were developed using a wide variety of software technologies. These, which included relational databases, web services, software management technologies, and 3-D graphics in Java, were necessary to integrate the heterogeneous array of data sources which comprise our software. Currently the interns are working to integrate new technologies and larger data sets to increase software functionality and value. In addition, both LA3D and SCEC-VIDEO allow the user to script and create movies. Thus program interns with computer science backgrounds have been writing software while interns with other interests, such as cinema, geology, and education, have been making movies that have proved of great use in scientific talks, media interviews, and education. Thus, SCEC UseIT incorporates a wide variety of scientific and human resources to create products of value to the scientific and outreach communities. The program plans to continue with its interdisciplinary approach, increasing the relevance of the software and expanding its use in the scientific community.

Visual masking and the dynamics of human perception, cognition, and consciousness A century of progress, a contemporary synthesis, and future directions.

PubMed

Ansorge, Ulrich; Francis, Gregory; Herzog, Michael H; Oğmen, Haluk

2008-07-15

The 1990s, the "decade of the brain," witnessed major advances in the study of visual perception, cognition, and consciousness. Impressive techniques in neurophysiology, neuroanatomy, neuropsychology, electrophysiology, psychophysics and brain-imaging were developed to address how the nervous system transforms and represents visual inputs. Many of these advances have dealt with the steady-state properties of processing. To complement this "steady-state approach," more recent research emphasized the importance of dynamic aspects of visual processing. Visual masking has been a paradigm of choice for more than a century when it comes to the study of dynamic vision. A recent workshop (http://lpsy.epfl.ch/VMworkshop/), held in Delmenhorst, Germany, brought together an international group of researchers to present state-of-the-art research on dynamic visual processing with a focus on visual masking. This special issue presents peer-reviewed contributions by the workshop participants and provides a contemporary synthesis of how visual masking can inform the dynamics of human perception, cognition, and consciousness.

Visual masking and the dynamics of human perception, cognition, and consciousness A century of progress, a contemporary synthesis, and future directions

PubMed Central

Ansorge, Ulrich; Francis, Gregory; Herzog, Michael H.; Öğmen, Haluk

2008-01-01

The 1990s, the “decade of the brain,” witnessed major advances in the study of visual perception, cognition, and consciousness. Impressive techniques in neurophysiology, neuroanatomy, neuropsychology, electrophysiology, psychophysics and brain-imaging were developed to address how the nervous system transforms and represents visual inputs. Many of these advances have dealt with the steady-state properties of processing. To complement this “steady-state approach,” more recent research emphasized the importance of dynamic aspects of visual processing. Visual masking has been a paradigm of choice for more than a century when it comes to the study of dynamic vision. A recent workshop (http://lpsy.epfl.ch/VMworkshop/), held in Delmenhorst, Germany, brought together an international group of researchers to present state-of-the-art research on dynamic visual processing with a focus on visual masking. This special issue presents peer-reviewed contributions by the workshop participants and provides a contemporary synthesis of how visual masking can inform the dynamics of human perception, cognition, and consciousness. PMID:20517493

Urethral calculi in young-adult Nigerian males: a case series.

PubMed

Gali, B M; Ali, N; Agbese, G O; Garba, I I; Musa, K

2011-01-01

Urethral calculi are rare and usually encountered in males with urethral pathology. To present our experience managing urethral calculi in a resource limited centre and review the literature. We did a chart review of management of patients with urethral calculi between January and April 2009, at Federal Medical Centre (FMC) Azare, Nigeria. We also reviewed the literature on this rare condition. Four young adult male Nigerians between the ages of 17 and 27 years presented with varying degrees of urethral pain and palpable calculi in the anterior urethra. Two presented with acute retention of urine, but none had haematuria. The calculi were radio-opaque, located in the anterior urethra with no associated urethral pathology. Three were solitary and one multiple. The composition of the urethral calculi was a mixture of calcium oxalate calcium carbonate, magnesium phosphate, one has additional cystine but none had struvite or uric acid. Their sizes ranged between 1cm ×1.5cm and 1.5cm × 5.5cm. External urethrotomy was the method of treatment. Urethral calculi are rare in our setting, with no clear identifiable aetiological factors which suggests urinary schistosomiasisbeing associsted. The occurrence of urethral calculi appears to have a relationship with childhood urinary schistosomasis.

Use of an Absorbable Urethral Stent for the Management of a Urethral Stricture in a Stallion.

PubMed

Trela, Jan M; Dechant, Julie E; Culp, William T; Whitcomb, Mary B; Palm, Carrie A; Nieto, Jorge E

2016-11-01

To describe the successful management of a urethral stricture with an absorbable stent in a stallion. Clinical report. Stallion with a urethral stricture. A 12-year-old Thoroughbred breeding stallion was evaluated for acute onset of colic. Uroperitoneum because of presumptive urinary bladder rupture, with urethral obstruction by a urethrolith, was diagnosed. The uroperitoneum was treated conservatively. The urethrolith was removed through a perineal urethrotomy. Approximately 15 weeks after urethrolith removal, the stallion presented with a urethral stricture. The stricture was unsuccessfully treated with an indwelling urinary catheter and 4 attempts at balloon dilation. Eight weeks after diagnosis of stricture, an absorbable polydioxanone (20 mm × 80 mm) urethral stent was implanted under percutaneous, ultrasound guidance. Urethroscopy was performed at 70, 155, and 230 days after stent placement and the endoscope passed through the affected site without complication. Urethroscopy at 155 days showed the stent had been reabsorbed. Follow-up 20 months after stent placement reports the stallion was able to void a normal urine stream. Absorbable urethral stent placement was a feasible treatment for urethral stricture in this stallion. © Copyright 2016 by The American College of Veterinary Surgeons.

Use of plain radiography in the diagnosis, surgical management, and postoperative treatment of obstructive urolithiasis in 25 goats and 2 sheep.

PubMed

Kinsley, Marc A; Semevolos, Stacy; Parker, Jill E; Duesterdieck-Zellmer, Katja; Huber, Michael

2013-08-01

To describe use of plain radiography for diagnosis, surgical management, and postoperative treatment of obstructive urolithiasis in small ruminants. Retrospective case series. Small ruminants (n = 27; 25 goats, 2 sheep). Medical records (January 2002-November 2011) and radiographs for all small ruminants diagnosed with obstructive urolithiasis and having plain abdominal radiographs were reviewed. Signalment, surgical procedures, radiographic findings, ultrasonographic findings, position of calculi, and how plain radiography influenced surgical management and postoperative treatment were recorded. Radiopaque urinary calculi were detected in 23 (85%) plain radiographic studies. Location of uroliths determined by plain radiography included: cystic only (n = 5), distal to the sigmoid flexure and cystic (5), subischial (5), distal to the sigmoid flexure only (3), sigmoid flexure (3), and subischial and cystic (2). In 8 of these animals, postoperative radiographs revealed residual calculi in the urethra and were essential for their targeted removal by urethrotomy in 7 animals. In regions where radiopaque calculi (calcium carbonate, calcium oxalate, silica) are commonly encountered in small ruminants, plain radiographs are recommended to determine the appropriate surgical approach(es) and to confirm resolution of the obstruction. © Copyright 2013 by The American College of Veterinary Surgeons.

Flow visualization V; Proceedings of the 5th International Symposium, Prague, Czechoslovakia, Aug. 21-25, 1989

NASA Astrophysics Data System (ADS)

Reznicek, R.

The present conference on flow visualization encompasses methods exploiting tracing particles, surface tracing methods, methods exploiting the effects of streaming fluid on passing radiation/field, computer-aided flow visualization, and applications to fluid mechanics, aerodynamics, flow devices, shock tubes, and heat/mass transfer. Specific issues include visualizing velocity distribution by stereo photography, dark-field Fourier quasiinterferometry, speckle tomography of an open flame, a fast eye for real-time image analysis, and velocity-field determination based on flow-image analysis. Also addressed are flows around rectangular prisms with oscillating flaps at the leading edges, the tomography of aerodynamic objects, the vapor-screen technique applied to a delta-wing aircraft, flash-lamp planar imaging, IR-thermography applications in convective heat transfer, and the visualization of marangoni effects in evaporating sessile drops.

Visual Impairment and Intracranial Hypertension: An Emerging Spaceflight Risk

NASA Technical Reports Server (NTRS)

Taddeo, Terrance A.

2010-01-01

During recent long duration missions to the International Space Station (ISS) crewmembers have reported changes in visual acuity or visual field defects. Exams in the postflight period revealed changes to the visual system and elevated intracranial pressures. As a result, NASA Space Medicine has added a number of tests to be performed in the preflight, inflight and postflight periods for ISS and shuttle missions with the goal of determining the processes at work and any potential mitigation strategies. This discussion will acquaint you with the changes that NASA has made to its medical requirements in order to address the microgravity induced intracranial hypertension and associated visual changes. Key personnel have been assembled to provide you information on this topic. Educational Objectives: Provide an overview of the current Medical Operations requirements and the mitigation steps taken to operationally address the issue.

Age-related changes in conjunctive visual search in children with and without ASD.

PubMed

Iarocci, Grace; Armstrong, Kimberly

2014-04-01

Visual-spatial strengths observed among people with autism spectrum disorder (ASD) may be associated with increased efficiency of selective attention mechanisms such as visual search. In a series of studies, researchers examined the visual search of targets that share features with distractors in a visual array and concluded that people with ASD showed enhanced performance on visual search tasks. However, methodological limitations, the small sample sizes, and the lack of developmental analysis have tempered the interpretations of these results. In this study, we specifically addressed age-related changes in visual search. We examined conjunctive visual search in groups of children with (n = 34) and without ASD (n = 35) at 7-9 years of age when visual search performance is beginning to improve, and later, at 10-12 years, when performance has improved. The results were consistent with previous developmental findings; 10- to 12-year-old children were significantly faster visual searchers than their 7- to 9-year-old counterparts. However, we found no evidence of enhanced search performance among the children with ASD at either the younger or older ages. More research is needed to understand the development of visual search in both children with and without ASD. © 2014 International Society for Autism Research, Wiley Periodicals, Inc.

Pediatric Bulbar and Posterior Urethral Injuries: Operative Outcomes and Long-Term Follow-Up.

PubMed

Trachta, Jan; Moravek, Jiri; Kriz, Jan; Padr, Radek; Skaba, Richard

2016-02-01

The aim of this study was to analyze complications and outcomes of end-to-end urethral anastomosis performed for posttraumatic bulbar strictures or posterior urethral injuries in pediatric patients. The records of 15 boys, age 18 years and below, admitted to our tertiary trauma center with urethral injuries from 1989 to 2014 were reviewed retrospectively. Out of these 15 boys, 7 were excluded (2 for iatrogenic trauma, 2 for minor straddle injuries who were not operated on, 2 for incomplete records, and 1 lost to follow-up) and 8 analyzed patients were operated for bulbar or posterior urethral injury. The mean follow-up after the operation was 4.5 years (range 0.5-10). To obtain up-to-date follow-up information, all the analyzed patients were contacted by a letter and telephone in January 2015 and asked about lower urinary tract or erectile dysfunction (ED) using the International Index of Erectile Function-5 questionnaire. Mean age at the time of injury was 12.3 years (range 5-17). Four patients with pelvic fracture had complete posterior urethra disruption, three patients after straddle injury developed obliterating stricture of the bulbar urethra and one patient had torn his bulbar urethra apart by a sharp hook. Except for the immediate exploration of the open perineal wound, all patients were operated via perineal approach 1 to 6 months after initial suprapubic catheter insertion. Five patients needed a cystotomy to identify the proximal urethral stump by a probe, and two patients had partial pubectomy to gain urethral length. Postoperative complications included stricture in anastomosis in six patients (all reoperated, four more than once including attempts of endoscopic internal urethrotomy). Six days after surgery, one patient developed massive external bleeding around a permanent urinary catheter due to a posttraumatic ruptured arterial aneurysm that was later stopped by urgent angiography and coil insertion. After discharge, three patients had transient stress incontinence. All patients had uroflowmetry maximum flow above 20 mL/s on their last follow-up except for two (12 and 15 mL/s). None have any lower urinary tract dysfunction symptoms in adulthood; one suffers from mild ED and two report moderate ED due to penile shortening. Delayed end-to-end anastomosis for pediatric urethral injury is a safe operational option. However, high rate of short-term complications and reoperations should be expected. Penile shortening is one of the most severe long-term complications. Georg Thieme Verlag KG Stuttgart · New York.

Addiction to melodrama.

PubMed

Stephens, Robert P

2011-01-01

Addiction films have been shaped by the internal demands of a commercial medium. Specifically, melodrama, as a genre, has defined the limits of the visual representation of addiction. Similarly, the process of intermedialization has tended to induce a metamorphosis that shapes disparate narratives with diverse goals into a generic filmic form and substantially alters the meanings of the texts. Ultimately, visual representations shape public perceptions of addiction in meaningful ways, privileging a moralistic understanding of drug addiction that makes a complex issue visually uncomplicated by reinforcing "common sense" ideas of moral failure and redemption. Copyright © 2011 Informa Healthcare USA, Inc.

The Influence of Texture Symmetry in Marker Pointing:. Experimenting with Humans and Algorithms

NASA Astrophysics Data System (ADS)

Cardaci, M.; Tabacchi, M. E.

2012-12-01

Symmetry plays a fundamental role in aiding the visual system, to organize its environmental stimuli and to detect visual patterns of natural and artificial objects. Various kinds of symmetry exist, and we will discuss how internal symmetry due to textures influences the choice of direction in visual tasks. Two experiments are presented: the first, with human subjects, deals with the effect of textures on preferences for a pointing direction. The second emulates the performances obtained in the first through the use of an algorithm based on a physic metaphor. Results from both experiments are shown and comment.

The effect of internal and external fields of view on visually induced motion sickness.

PubMed

Bos, Jelte E; de Vries, Sjoerd C; van Emmerik, Martijn L; Groen, Eric L

2010-07-01

Field of view (FOV) is said to affect visually induced motion sickness. FOV, however, is characterized by an internal setting used by the graphics generator (iFOV) and an external factor determined by screen size and viewing distance (eFOV). We hypothesized that especially the incongruence between iFOV and eFOV would lead to sickness. To that end we used a computer game environment with different iFOV and eFOV settings, and found the opposite effect. We speculate that the relative large differences between iFOV and eFOV used in this experiment caused the discrepancy, as may be explained by assuming an observer model controlling body motion. Copyright 2009 Elsevier Ltd. All rights reserved.

Damage analysis of CF/AF hybrid fabric reinforced plastic laminated composites with scanned image microscopy

NASA Astrophysics Data System (ADS)

Miyasaka, Chiaki; Kasano, Hideaki; Shull, Peter J.

2004-07-01

The article presents an experimental study that has been conducted to evaluate the impact loading damage within hybrid fabric laminates-carbon and Aramid fibers. The experiments have been undertaken on a series of interply hybrid specimens with different preprags stacking sequences. Impact damage was created using an air-gun like impact device propelling spherical steel balls with diameters of 5.0mm and 10.0mm and having velocities of 113m/s and 40m/s respectively. The resulting specimen surface and internal damage (e.g., micro-cracking and debonding) was visualized nondestructively by a scanning acoustic microscope (SAM) while further interrogation of specific internal damage was visualized using a scanning electron microscope (SEM) on cross-sectioned panels.

Internal models and prediction of visual gravitational motion.

PubMed

Zago, Myrka; McIntyre, Joseph; Senot, Patrice; Lacquaniti, Francesco

2008-06-01

Baurès et al. [Baurès, R., Benguigui, N., Amorim, M.-A., & Siegler, I. A. (2007). Intercepting free falling objects: Better use Occam's razor than internalize Newton's law. Vision Research, 47, 2982-2991] rejected the hypothesis that free-falling objects are intercepted using a predictive model of gravity. They argued instead for "a continuous guide for action timing" based on visual information updated till target capture. Here we show that their arguments are flawed, because they fail to consider the impact of sensori-motor delays on interception behaviour and the need for neural compensation of such delays. When intercepting a free-falling object, the delays can be overcome by a predictive model of the effects of gravity on target motion.

Socioeconomic consequences of blinding onchocerciasis in west Africa.

PubMed Central

Evans, T. G.

1995-01-01

Onchocerciasis or river blindness, a major cause of irreversible blindness among adults, has been the focus of international disease control efforts for over 20 years in West Africa. This paper employs the international classification of impairment, disability and handicap (ICIDH) to interpret results from a field study to assess the socioeconomic consequences of onchocerciasis in Guinea in 1987. In a sample of 136 blind, 94 visually impaired and 89 well-sighted persons, decreasing visual acuity is strongly associated with mobility, occupational and marital handicaps. Individual, household and disease correlates were explored. The implications of these findings for the ICIDH concept of handicap are discussed with particular emphasis on the need to extend analysis beyond the individual when assessing the socioeconomic consequences of disabling disease. PMID:7554022

Visual imagery and functional connectivity in blindness: a single-case study

PubMed Central

Boucard, Christine C.; Rauschecker, Josef P.; Neufang, Susanne; Berthele, Achim; Doll, Anselm; Manoliu, Andrej; Riedl, Valentin; Sorg, Christian; Wohlschläger, Afra; Mühlau, Mark

2016-01-01

We present a case report on visual brain plasticity after total blindness acquired in adulthood. SH lost her sight when she was 27. Despite having been totally blind for 43 years, she reported to strongly rely on her vivid visual imagery. Three-Tesla magnetic resonance imaging (MRI) of SH and age-matched controls was performed. The MRI sequence included anatomical MRI, resting-state functional MRI, and task-related functional MRI where SH was instructed to imagine colours, faces, and motion. Compared to controls, voxel-based analysis revealed white matter loss along SH's visual pathway as well as grey matter atrophy in the calcarine sulci. Yet we demonstrated activation in visual areas, including V1, using functional MRI. Of the four identified visual resting-state networks, none showed alterations in spatial extent; hence, SH's preserved visual imagery seems to be mediated by intrinsic brain networks of normal extent. Time courses of two of these networks showed increased correlation with that of the inferior posterior default mode network, which may reflect adaptive changes supporting SH's strong internal visual representations. Overall, our findings demonstrate that conscious visual experience is possible even after years of absence of extrinsic input. PMID:25690326

Visual imagery and functional connectivity in blindness: a single-case study.

PubMed

Boucard, Christine C; Rauschecker, Josef P; Neufang, Susanne; Berthele, Achim; Doll, Anselm; Manoliu, Andrej; Riedl, Valentin; Sorg, Christian; Wohlschläger, Afra; Mühlau, Mark

2016-05-01

We present a case report on visual brain plasticity after total blindness acquired in adulthood. SH lost her sight when she was 27. Despite having been totally blind for 43 years, she reported to strongly rely on her vivid visual imagery. Three-Tesla magnetic resonance imaging (MRI) of SH and age-matched controls was performed. The MRI sequence included anatomical MRI, resting-state functional MRI, and task-related functional MRI where SH was instructed to imagine colours, faces, and motion. Compared to controls, voxel-based analysis revealed white matter loss along SH's visual pathway as well as grey matter atrophy in the calcarine sulci. Yet we demonstrated activation in visual areas, including V1, using functional MRI. Of the four identified visual resting-state networks, none showed alterations in spatial extent; hence, SH's preserved visual imagery seems to be mediated by intrinsic brain networks of normal extent. Time courses of two of these networks showed increased correlation with that of the inferior posterior default mode network, which may reflect adaptive changes supporting SH's strong internal visual representations. Overall, our findings demonstrate that conscious visual experience is possible even after years of absence of extrinsic input.

Development of the Preverbal Visual Assessment (PreViAs) questionnaire.

PubMed

Pueyo, Victoria; García-Ormaechea, Inés; González, Inmaculada; Ferrer, Concepción; de la Mata, Guillermo; Duplá, María; Orós, Pedro; Andres, Eva

2014-04-01

Visual cognitive functions of preverbal infants are evaluated by means of a behavioral assessment. Parents or primary caregivers may be appropriate to certify the acquisition of certain abilities. To develop the PreViAs (Preverbal Visual Assessment) questionnaire to assess visual behavior of infants under 24 months of age and to assess the normative outcomes for each item at each age. The process was divided into three phases: scale development (items and domains generation), pilot testing, and exploratory analysis. The final version of the PreViAs questionnaire consisted of 30 items, each related to one or more of four domains (visual attention, visual communication, visual-motor coordination, and visual processing). For the exploratory analysis, 298 children (159 boys and 139 girls) were recruited. Their ages ranged from 0.1 to 24 months (mean, 11.2 months). Internal consistency of the questionnaire was high for all domains (Cronbach's α coefficients of 0.85-0.94). The PreViAs questionnaire is a useful scale for assessing visual cognitive abilities of infants under 24 months of age. It is easy and feasible to complete by primary caregivers. Copyright © 2014 Elsevier Ltd. All rights reserved.

Visual feature integration theory: past, present, and future.

PubMed

Quinlan, Philip T

2003-09-01

Visual feature integration theory was one of the most influential theories of visual information processing in the last quarter of the 20th century. This article provides an exposition of the theory and a review of the associated data. In the past much emphasis has been placed on how the theory explains performance in various visual search tasks. The relevant literature is discussed and alternative accounts are described. Amendments to the theory are also set out. Many other issues concerning internal processes and representations implicated by the theory are reviewed. The article closes with a synopsis of what has been learned from consideration of the theory, and it is concluded that some of the issues may remain intractable unless appropriate neuroscientific investigations are carried out.

Calculating and Visualizing Thermodynamic Equilibrium: A Tutorial on the Isolated System with an Internal Adiabatic Piston

ERIC Educational Resources Information Center

Ferreira, Joao Paulo M.

2007-01-01

The problem of the equilibrium state of an isolated composite system with a movable internal adiabatic wall is a recurrent one in the literature. Classical equilibrium thermodynamics is unable to predict the equilibrium state, unless supplemented with information about the process taking place. This conclusion is clearly demonstrated in this…

More than a Body's Work: Widening Cultural Participation through an International Exploration of Young People's Construction of Visual Image and Identity

ERIC Educational Resources Information Center

Bianchi, June

2008-01-01

The article presents the rationale, methodology, and selected outcomes from "More than a body's work," a collaborative, international, arts educational interactive research project. The project, taking place in both New York and England, explored the ways in which young people construct and "perform" identity through the…

Information and Communication Technology in the Classroom: An Empirical Study with an International Perspective.

ERIC Educational Resources Information Center

Mueller, Carolyn B.; Jones, Gordon; Ricks, David A.; Schlegelmilch, Bodo B.; Van Deusen, Cheryl A.

2001-01-01

Surveyed international business faculty in 14 countries about their perceptions and use of information and communication technology (ICT) in the classroom. Faculty believe the primary advantages of ICT are that they provide positive impact on visual as well as audio learners, and promote greater understanding, excitement, and student interest.…

Using Geowall to Promote Undergraduate Research

NASA Astrophysics Data System (ADS)

Scec EIT Intern Team; Perry, S.; Jordan, T.

2003-12-01

The principal use of our Geowall system is to showcase the 3-D visualizations created by SCEC/EITR (Southern California Earthquake Center/Earthquake Information Technology Research) interns. These visualizations, called LA3D, are devised to educate the public, assist researchers, inspire students, and attract new interns. With the design criteria that LA3D code must be object-oriented and open-source, and that all datasets should be in internet-accessible databases, our interns have made interactive visualizations of southern California's earthquakes, faults, landforms, and other topographic features, that allow unlimited additions of new datasets and map objects. The interns built our Geowall system, and made a unique contribution to the Geowall consortium when they devised a simple way to use Java3D to create and send images to Geowall's projectors. The EIT interns are enormously proud of their accomplishments, and for most, working on LA3D has been the high point of their college careers. Their efforts have become central to testbed development of the system level science that SCEC is orchestrating in its Community Modeling Environment. In addition, SCEC's Communication, Education and Outreach Program uses LA3D on Geowall to communicate concepts about earthquakes and earthquake processes. Then, projecting LA3D on Geowall, it becomes easy to impress students from elementary to high school ages with what can be accomplished if they keep learning math and science. Finally, we bring Geowall to undergraduate research symposia and career-day open houses, to project LA3D and attract additional students to our intern program, which to date has united students in computer science, engineering, geoscience, mathematics, communication, pre-law, and cinema. (Note: distribution copies of LA3D will be available in early 2004.) The Southern California Earthquake Center Earthquake Information Technology Intern Team on this project: Adam Bongarzone, Hunter Francoeur, Lindsay Gordon, Nitin Gupta, Vipin Gupta, Jeff Hoeft, Shalini Jhatakia, Leonard Jimenez, Gideon Juve, Douglas Lam, Jed Link, Gavin Locke, Deepak Mehtani, Bill Paetzke, Nick Palmer, Brandee Pierce, Ryan Prose, Nitin Sharma, Ghunghroo Sinha, Jeremie Smith, Brandon Teel, Robert Weekly, Channing Wong, Jeremy Zechar.

Interactive 3D visualization of structural changes in the brain of a person with corticobasal syndrome

PubMed Central

Hänel, Claudia; Pieperhoff, Peter; Hentschel, Bernd; Amunts, Katrin; Kuhlen, Torsten

2014-01-01

The visualization of the progression of brain tissue loss in neurodegenerative diseases like corticobasal syndrome (CBS) can provide not only information about the localization and distribution of the volume loss, but also helps to understand the course and the causes of this neurodegenerative disorder. The visualization of such medical imaging data is often based on 2D sections, because they show both internal and external structures in one image. Spatial information, however, is lost. 3D visualization of imaging data is capable to solve this problem, but it faces the difficulty that more internally located structures may be occluded by structures near the surface. Here, we present an application with two designs for the 3D visualization of the human brain to address these challenges. In the first design, brain anatomy is displayed semi-transparently; it is supplemented by an anatomical section and cortical areas for spatial orientation, and the volumetric data of volume loss. The second design is guided by the principle of importance-driven volume rendering: A direct line-of-sight to the relevant structures in the deeper parts of the brain is provided by cutting out a frustum-like piece of brain tissue. The application was developed to run in both, standard desktop environments and in immersive virtual reality environments with stereoscopic viewing for improving the depth perception. We conclude, that the presented application facilitates the perception of the extent of brain degeneration with respect to its localization and affected regions. PMID:24847243

Activity in human visual and parietal cortex reveals object-based attention in working memory.

PubMed

Peters, Benjamin; Kaiser, Jochen; Rahm, Benjamin; Bledowski, Christoph

2015-02-25

Visual attention enables observers to select behaviorally relevant information based on spatial locations, features, or objects. Attentional selection is not limited to physically present visual information, but can also operate on internal representations maintained in working memory (WM) in service of higher-order cognition. However, only little is known about whether attention to WM contents follows the same principles as attention to sensory stimuli. To address this question, we investigated in humans whether the typically observed effects of object-based attention in perception are also evident for object-based attentional selection of internal object representations in WM. In full accordance with effects in visual perception, the key behavioral and neuronal characteristics of object-based attention were observed in WM. Specifically, we found that reaction times were shorter when shifting attention to memory positions located on the currently attended object compared with equidistant positions on a different object. Furthermore, functional magnetic resonance imaging and multivariate pattern analysis of visuotopic activity in visual (areas V1-V4) and parietal cortex revealed that directing attention to one position of an object held in WM also enhanced brain activation for other positions on the same object, suggesting that attentional selection in WM activates the entire object. This study demonstrated that all characteristic features of object-based attention are present in WM and thus follows the same principles as in perception. Copyright © 2015 the authors 0270-6474/15/353360-10$15.00/0.

Impaired downregulation of visual cortex during auditory processing is associated with autism symptomatology in children and adolescents with autism spectrum disorder.

PubMed

Jao Keehn, R Joanne; Sanchez, Sandra S; Stewart, Claire R; Zhao, Weiqi; Grenesko-Stevens, Emily L; Keehn, Brandon; Müller, Ralph-Axel

2017-01-01

Autism spectrum disorders (ASD) are pervasive developmental disorders characterized by impairments in language development and social interaction, along with restricted and stereotyped behaviors. These behaviors often include atypical responses to sensory stimuli; some children with ASD are easily overwhelmed by sensory stimuli, while others may seem unaware of their environment. Vision and audition are two sensory modalities important for social interactions and language, and are differentially affected in ASD. In the present study, 16 children and adolescents with ASD and 16 typically developing (TD) participants matched for age, gender, nonverbal IQ, and handedness were tested using a mixed event-related/blocked functional magnetic resonance imaging paradigm to examine basic perceptual processes that may form the foundation for later-developing cognitive abilities. Auditory (high or low pitch) and visual conditions (dot located high or low in the display) were presented, and participants indicated whether the stimuli were "high" or "low." Results for the auditory condition showed downregulated activity of the visual cortex in the TD group, but upregulation in the ASD group. This atypical activity in visual cortex was associated with autism symptomatology. These findings suggest atypical crossmodal (auditory-visual) modulation linked to sociocommunicative deficits in ASD, in agreement with the general hypothesis of low-level sensorimotor impairments affecting core symptomatology. Autism Res 2017, 10: 130-143. © 2016 International Society for Autism Research, Wiley Periodicals, Inc. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

Multiresolution Algorithms for Processing Giga-Models: Real-time Visualization, Reasoning, and Interaction

DTIC Science & Technology

2012-04-23

Interactive Virtual Hair Salon , Presence, (05 2007): 237. doi: 2012/04/17 12:55:26 31 Theodore Kim, Jason Sewall, Avneesh Sud, Ming Lin. Fast...in Games , Utrecht, Netherlands, Nov. 2009. Keynote Speaker, IADIS International Conference on Computer Graphics and Visualization, Portugal, June 2009...Keynote Speaker, ACM Symposium on Virtual Reality Software and Technology, Bordeaux, France, October 2008. Invited Speaker, Motion in Games , Utrecht

Pollen structure visualization using high-resolution laboratory-based hard X-ray tomography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Qiong; Gluch, Jürgen; Krüger, Peter

A laboratory-based X-ray microscope is used to investigate the 3D structure of unstained whole pollen grains. For the first time, high-resolution laboratory-based hard X-ray microscopy is applied to study pollen grains. Based on the efficient acquisition of statistically relevant information-rich images using Zernike phase contrast, both surface- and internal structures of pine pollen - including exine, intine and cellular structures - are clearly visualized. The specific volumes of these structures are calculated from the tomographic data. The systematic three-dimensional study of pollen grains provides morphological and structural information about taxonomic characters that are essential in palynology. Such studies have amore » direct impact on disciplines such as forestry, agriculture, horticulture, plant breeding and biodiversity. - Highlights: • The unstained whole pine pollen was visualized by high-resolution laboratory-based HXRM for the first time. • The comparison study of pollen grains by LM, SEM and high-resolution laboratory-based HXRM. • Phase contrast imaging provides significantly higher contrast of the raw images compared to absorption contrast imaging. • Surface and internal structure of the pine pollen including exine, intine and cellular structures are clearly visualized. • 3D volume data of unstained whole pollen grains are acquired and the specific volumes of the different layer are calculated.« less

Vibrotactile timing: Are vibrotactile judgements of duration affected by repetitive stimulation?

PubMed

Jones, Luke A; Ogden, Ruth S

2016-01-01

Timing in the vibrotactile modality was explored. Previous research has shown that repetitive auditory stimulation (in the form of click-trains) and visual stimulation (in the form of flickers) can alter duration judgements in a manner consistent with a "speeding up" of an internal clock. In Experiments 1 and 2 we investigated whether repetitive vibrotactile stimulation in the form of vibration trains would also alter duration judgements of either vibrotactile stimuli or visual stimuli. Participants gave verbal estimates of the duration of vibrotactile and visual stimuli that were preceded either by five seconds of 5-Hz vibration trains, or, by a five-second period of no vibrotactile stimulation, the end of which was signalled by a single vibration pulse (control condition). The results showed that durations were overestimated in the vibrotactile train conditions relative to the control condition; however, the effects were not multiplicative (did not increase with increasing stimulus duration) and as such were not consistent with a speeding up of the internal clock, but rather with an additive attentional effect. An additional finding was that the slope of the vibrotactile psychometric (control condition) function was not significantly different from that of the visual (control condition) function, which replicates a finding from a previous cross-modal comparison of timing.

A Cross-Modal Perspective on the Relationships between Imagery and Working Memory

PubMed Central

Likova, Lora T.

2013-01-01

Mapping the distinctions and interrelationships between imagery and working memory (WM) remains challenging. Although each of these major cognitive constructs is defined and treated in various ways across studies, most accept that both imagery and WM involve a form of internal representation available to our awareness. In WM, there is a further emphasis on goal-oriented, active maintenance, and use of this conscious representation to guide voluntary action. Multicomponent WM models incorporate representational buffers, such as the visuo-spatial sketchpad, plus central executive functions. If there is a visuo-spatial “sketchpad” for WM, does imagery involve the same representational buffer? Alternatively, does WM employ an imagery-specific representational mechanism to occupy our awareness? Or do both constructs utilize a more generic “projection screen” of an amodal nature? To address these issues, in a cross-modal fMRI study, I introduce a novel Drawing-Based Memory Paradigm, and conceptualize drawing as a complex behavior that is readily adaptable from the visual to non-visual modalities (such as the tactile modality), which opens intriguing possibilities for investigating cross-modal learning and plasticity. Blindfolded participants were trained through our Cognitive-Kinesthetic Method (Likova, 2010a, 2012) to draw complex objects guided purely by the memory of felt tactile images. If this WM task had been mediated by transfer of the felt spatial configuration to the visual imagery mechanism, the response-profile in visual cortex would be predicted to have the “top-down” signature of propagation of the imagery signal downward through the visual hierarchy. Remarkably, the pattern of cross-modal occipital activation generated by the non-visual memory drawing was essentially the inverse of this typical imagery signature. The sole visual hierarchy activation was isolated to the primary visual area (V1), and accompanied by deactivation of the entire extrastriate cortex, thus ’cutting-off’ any signal propagation from/to V1 through the visual hierarchy. The implications of these findings for the debate on the interrelationships between the core cognitive constructs of WM and imagery and the nature of internal representations are evaluated. PMID:23346061

Almost equivalence of combinatorial and distance processes for discrimination in multielement images.

PubMed

Ferraro, M; Foster, D H

1991-01-01

Under certain experimental conditions, visual discrimination performance in multielement images is closely related to visual identification performance: elements of the image are distinguished only insofar as they appear to have distinct, discrete, internal characterizations. This report is concerned with the detailed relationship between such internal characterizations and observable discrimination performance. Two types of general processes that might underline discrimination are considered. The first is based on computing all possible internal image characterizations that could allow a correct decision, each characterization weighted by the probability of its occurrence and of a correct decision being made. The second process is based on computing the difference between the probabilities associated with the internal characterizations of the individual image elements, the difference quantified naturally with an l(p) norm. The relationship between the two processes was investigated analytically and by Monte Carlo simulations over a plausible range of numbers n of the internal characterizations of each of the m elements in the image. The predictions of the two processes were found to be closely similar. The relationship was precisely one-to-one, however, only for n = 2, m = 3, 4, 6, and for n greater than 2, m = 3, 4, p = 2. For all other cases tested, a one-to-one relationship was shown to be impossible.

Subliminal repetition primes help detection of phonemes in a picture: Evidence for a phonological level of the priming effects.

PubMed

Manoiloff, Laura; Segui, Juan; Hallé, Pierre

2016-01-01

In this research, we combine a cross-form word-picture visual masked priming procedure with an internal phoneme monitoring task to examine repetition priming effects. In this paradigm, participants have to respond to pictures whose names begin with a prespecified target phoneme. This task unambiguously requires retrieving the word-form of the target picture's name and implicitly orients participants' attention towards a phonological level of representation. The experiments were conducted within Spanish, whose highly transparent orthography presumably promotes fast and automatic phonological recoding of subliminal, masked visual word primes. Experiments 1 and 2 show that repetition primes speed up internal phoneme monitoring in the target, compared to primes beginning with a different phoneme from the target, or sharing only their first phoneme with the target. This suggests that repetition primes preactivate the phonological code of the entire target picture's name, hereby speeding up internal monitoring, which is necessarily based on such a code. To further qualify the nature of the phonological code underlying internal phoneme monitoring, a concurrent articulation task was used in Experiment 3. This task did not affect the repetition priming effect. We propose that internal phoneme monitoring is based on an abstract phonological code, prior to its translation into articulation.

Functional Role of Internal and External Visual Imagery: Preliminary Evidences from Pilates

PubMed Central

Montuori, Simone; Sorrentino, Pierpaolo; Belloni, Lidia; Sorrentino, Giuseppe

2018-01-01

The present study investigates whether a functional difference between the visualization of a sequence of movements in the perspective of the first- (internal VMI-I) or third- (external VMI-E) person exists, which might be relevant to promote learning. By using a mental chronometry experimental paradigm, we have compared the time or execution, imagination in the VMI-I perspective, and imagination in the VMI-E perspective of two kinds of Pilates exercises. The analysis was carried out in individuals with different levels of competence (expert, novice, and no-practice individuals). Our results showed that in the Expert group, in the VMI-I perspective, the imagination time was similar to the execution time, while in the VMI-E perspective, the imagination time was significantly lower than the execution time. An opposite pattern was found in the Novice group, in which the time of imagination was similar to that of execution only in the VMI-E perspective, while in the VMI-I perspective, the time of imagination was significantly lower than the time of execution. In the control group, the times of both modalities of imagination were significantly lower than the execution time for each exercise. The present data suggest that, while the VMI-I serves to train an already internalised gesture, the VMI-E perspective could be useful to learn, and then improve, the recently acquired sequence of movements. Moreover, visual imagery is not useful for individuals that lack a specific motor experience. The present data offer new insights in the application of mental training techniques, especially in field of sports. However, further investigations are needed to better understand the functional role of internal and external visual imagery. PMID:29849565

Loop-Mediated Isothermal Amplification for Detection of Endogenous Sad1 Gene in Cotton: An Internal Control for Rapid Onsite GMO Testing.

PubMed

Singh, Monika; Bhoge, Rajesh K; Randhawa, Gurinderjit

2018-04-20

Background : Confirming the integrity of seed samples in powdered form is important priorto conducting a genetically modified organism (GMO) test. Rapid onsite methods may provide a technological solution to check for genetically modified (GM) events at ports of entry. In India, Bt cotton is the commercialized GM crop with four approved GM events; however, 59 GM events have been approved globally. GMO screening is required to test for authorized GM events. The identity and amplifiability of test samples could be ensured first by employing endogenous genes as an internal control. Objective : A rapid onsite detection method was developed for an endogenous reference gene, stearoyl acyl carrier protein desaturase ( Sad1 ) of cotton, employing visual and real-time loop-mediated isothermal amplification (LAMP). Methods : The assays were performed at a constant temperature of 63°C for 30 min for visual LAMP and 62ºC for 40 min for real-time LAMP. Positive amplification was visualized as a change in color from orange to green on addition of SYBR ® Green or detected as real-time amplification curves. Results : Specificity of LAMP assays was confirmed using a set of 10 samples. LOD for visual LAMP was up to 0.1%, detecting 40 target copies, and for real-time LAMP up to 0.05%, detecting 20 target copies. Conclusions : The developed methods could be utilized to confirm the integrity of seed powder prior to conducting a GMO test for specific GM events of cotton. Highlights : LAMP assays for the endogenous Sad1 gene of cotton have been developed to be used as an internal control for onsite GMO testing in cotton.

Activation of the rostromedial prefrontal cortex during the experience of positive emotion in the context of esthetic experience. An fNIRS study.

PubMed

Kreplin, Ute; Fairclough, Stephen H

2013-01-01

The contemplation of visual art requires attention to be directed to external stimulus properties and internally generated thoughts. It has been proposed that the medial rostral prefrontal cortex (rPFC; BA10) plays a role in the maintenance of attention on external stimuli whereas the lateral area of the rPFC is associated with the preservation of attention on internal cognitions. An alternative hypothesis associates activation of medial rPFC with internal cognitions related to the self during emotion regulation. The aim of the current study was to differentiate activation within rPFC using functional near infrared spectroscopy (fNIRS) during the viewing of visual art selected to induce positive and negative valence, which were viewed under two conditions: (1) emotional introspection and (2) external object identification. Thirty participants (15 female) were recruited. Sixteen pre-rated images that represented either positive or negative valence were selected from an existing database of visual art. In one condition, participants were directed to engage in emotional introspection during picture viewing. The second condition involved a spot-the-difference task where participants compared two almost identical images, a viewing strategy that directed attention to external properties of the stimuli. The analysis revealed a significant increase of oxygenated blood in the medial rPFC during viewing of positive images compared to negative images. This finding suggests that the rPFC is involved during positive evaluations of visual art that may be related to judgment of pleasantness or attraction. The fNIRS data revealed no significant main effect between the two viewing conditions, which seemed to indicate that the emotional impact of the stimuli remained unaffected by the two viewing conditions.

The advantage of CT scans and 3D visualizations in the analysis of three child mummies from the Graeco-Roman Period.

PubMed

Villa, Chiara; Davey, Janet; Craig, Pamela J G; Drummer, Olaf H; Lynnerup, Niels

2015-01-01

Three child mummies from the Graeco-Roman Period (332 BCE - c. 395 CE) were examined using CT scans and 3D visualizations generated with Vitrea 2 and MIMICS graphic workstations with the aim of comparing the results with previous X-ray examinations performed by Dawson and Gray in 1968. Although the previous analyses reported that the children had been excerebrated and eviscerated, no evidence of incisions or breaches of the cranial cavity were found; 3D visualizations were generated showing the brain and the internal organs to be in situ. A larger number of skeletal post-mortem damages were identified, such as dislocation of mandible, ribs, and vertebrae, probably suffered at the time of embalming procedure. Different radio-opaque granular particles were observed throughout bodies (internally and externally) and could be explained as presence of natron, used as external desiccating agent by the embalmers, or as adipocerous alteration, a natural alteration of body fat. Age-at-death was estimated using the 3D visualization of the teeth, the state of fusion of the vertebrae and the presence of the secondary centers of the long bones: two mummies died at the age of 4 years ± 12 months, the third one at the age of 6 years ± 24 months. Hyperdontia or polydontia, a dental anomaly, could also be identified in one child using 3D visualizations of the teeth: two supernumerary teeth were found behind the maxillary permanent central incisors which had not been noticed in the Dawson and Gray's X-ray analysis. In conclusion, CT-scan investigations and especially 3D visualizations are important tools in the non-invasive analysis of the mummies and, in this case, provided revised and additional information compared to the only X-ray examination.

A neural-visualization IDS for honeynet data.

PubMed

Herrero, Álvaro; Zurutuza, Urko; Corchado, Emilio

2012-04-01

Neural intelligent systems can provide a visualization of the network traffic for security staff, in order to reduce the widely known high false-positive rate associated with misuse-based Intrusion Detection Systems (IDSs). Unlike previous work, this study proposes an unsupervised neural models that generate an intuitive visualization of the captured traffic, rather than network statistics. These snapshots of network events are immensely useful for security personnel that monitor network behavior. The system is based on the use of different neural projection and unsupervised methods for the visual inspection of honeypot data, and may be seen as a complementary network security tool that sheds light on internal data structures through visual inspection of the traffic itself. Furthermore, it is intended to facilitate verification and assessment of Snort performance (a well-known and widely-used misuse-based IDS), through the visualization of attack patterns. Empirical verification and comparison of the proposed projection methods are performed in a real domain, where two different case studies are defined and analyzed.

Internal state of monkey primary visual cortex (V1) predicts figure-ground perception.

PubMed

Supèr, Hans; van der Togt, Chris; Spekreijse, Henk; Lamme, Victor A F

2003-04-15

When stimulus information enters the visual cortex, it is rapidly processed for identification. However, sometimes the processing of the stimulus is inadequate and the subject fails to notice the stimulus. Human psychophysical studies show that this occurs during states of inattention or absent-mindedness. At a neurophysiological level, it remains unclear what these states are. To study the role of cortical state in perception, we analyzed neural activity in the monkey primary visual cortex before the appearance of a stimulus. We show that, before the appearance of a reported stimulus, neural activity was stronger and more correlated than for a not-reported stimulus. This indicates that the strength of neural activity and the functional connectivity between neurons in the primary visual cortex participate in the perceptual processing of stimulus information. Thus, to detect a stimulus, the visual cortex needs to be in an appropriate state.

Eyes Matched to the Prize: The State of Matched Filters in Insect Visual Circuits.

PubMed

Kohn, Jessica R; Heath, Sarah L; Behnia, Rudy

2018-01-01

Confronted with an ever-changing visual landscape, animals must be able to detect relevant stimuli and translate this information into behavioral output. A visual scene contains an abundance of information: to interpret the entirety of it would be uneconomical. To optimally perform this task, neural mechanisms exist to enhance the detection of important features of the sensory environment while simultaneously filtering out irrelevant information. This can be accomplished by using a circuit design that implements specific "matched filters" that are tuned to relevant stimuli. Following this rule, the well-characterized visual systems of insects have evolved to streamline feature extraction on both a structural and functional level. Here, we review examples of specialized visual microcircuits for vital behaviors across insect species, including feature detection, escape, and estimation of self-motion. Additionally, we discuss how these microcircuits are modulated to weigh relevant input with respect to different internal and behavioral states.

Visual long-term memory has the same limit on fidelity as visual working memory.

PubMed

Brady, Timothy F; Konkle, Talia; Gill, Jonathan; Oliva, Aude; Alvarez, George A

2013-06-01

Visual long-term memory can store thousands of objects with surprising visual detail, but just how detailed are these representations, and how can one quantify this fidelity? Using the property of color as a case study, we estimated the precision of visual information in long-term memory, and compared this with the precision of the same information in working memory. Observers were shown real-world objects in random colors and were asked to recall the colors after a delay. We quantified two parameters of performance: the variability of internal representations of color (fidelity) and the probability of forgetting an object's color altogether. Surprisingly, the fidelity of color information in long-term memory was comparable to the asymptotic precision of working memory. These results suggest that long-term memory and working memory may be constrained by a common limit, such as a bound on the fidelity required to retrieve a memory representation.

The Value of Data and Metadata Standardization for Interoperability in Giovanni

NASA Astrophysics Data System (ADS)

Smit, C.; Hegde, M.; Strub, R. F.; Bryant, K.; Li, A.; Petrenko, M.

2017-12-01

Giovanni (https://giovanni.gsfc.nasa.gov/giovanni/) is a data exploration and visualization tool at the NASA Goddard Earth Sciences Data Information Services Center (GES DISC). It has been around in one form or another for more than 15 years. Giovanni calculates simple statistics and produces 22 different visualizations for more than 1600 geophysical parameters from more than 90 satellite and model products. Giovanni relies on external data format standards to ensure interoperability, including the NetCDF CF Metadata Conventions. Unfortunately, these standards were insufficient to make Giovanni's internal data representation truly simple to use. Finding and working with dimensions can be convoluted with the CF Conventions. Furthermore, the CF Conventions are silent on machine-friendly descriptive metadata such as the parameter's source product and product version. In order to simplify analyzing disparate earth science data parameters in a unified way, we developed Giovanni's internal standard. First, the format standardizes parameter dimensions and variables so they can be easily found. Second, the format adds all the machine-friendly metadata Giovanni needs to present our parameters to users in a consistent and clear manner. At a glance, users can grasp all the pertinent information about parameters both during parameter selection and after visualization. This poster gives examples of how our metadata and data standards, both external and internal, have both simplified our code base and improved our users' experiences.

The Word Shape Hypothesis Re-Examined: Evidence for an External Feature Advantage in Visual Word Recognition

ERIC Educational Resources Information Center

Beech, John R.; Mayall, Kate A.

2005-01-01

This study investigates the relative roles of internal and external letter features in word recognition. In Experiment 1 the efficacy of outer word fragments (words with all their horizontal internal features removed) was compared with inner word fragments (words with their outer features removed) as primes in a forward masking paradigm. These…

Validity and reliability of an online visual-spatial working memory task for self-reliant administration in school-aged children.

PubMed

Van de Weijer-Bergsma, Eva; Kroesbergen, Evelyn H; Prast, Emilie J; Van Luit, Johannes E H

2015-09-01

Working memory is an important predictor of academic performance, and of math performance in particular. Most working memory tasks depend on one-to-one administration by a testing assistant, which makes the use of such tasks in large-scale studies time-consuming and costly. Therefore, an online, self-reliant visual-spatial working memory task (the Lion game) was developed for primary school children (6-12 years of age). In two studies, the validity and reliability of the Lion game were investigated. The results from Study 1 (n = 442) indicated satisfactory six-week test-retest reliability, excellent internal consistency, and good concurrent and predictive validity. The results from Study 2 (n = 5,059) confirmed the results on the internal consistency and predictive validity of the Lion game. In addition, multilevel analysis revealed that classroom membership influenced Lion game scores. We concluded that the Lion game is a valid and reliable instrument for the online computerized and self-reliant measurement of visual-spatial working memory (i.e., updating).

A direct comparison of short-term audiomotor and visuomotor memory.

PubMed

Ward, Amanda M; Loucks, Torrey M; Ofori, Edward; Sosnoff, Jacob J

2014-04-01

Audiomotor and visuomotor short-term memory are required for an important variety of skilled movements but have not been compared in a direct manner previously. Audiomotor memory capacity might be greater to accommodate auditory goals that are less directly related to movement outcome than for visually guided tasks. Subjects produced continuous isometric force with the right index finger under auditory and visual feedback. During the first 10 s of each trial, subjects received continuous auditory or visual feedback. For the following 15 s, feedback was removed but the force had to be maintained accurately. An internal effort condition was included to test memory capacity in the same manner but without external feedback. Similar decay times of ~5-6 s were found for vision and audition but the decay time for internal effort was ~4 s. External feedback thus provides an advantage in maintaining a force level after feedback removal, but may not exclude some contribution from a sense of effort. Short-term memory capacity appears longer than certain previous reports but there may not be strong distinctions in capacity across different sensory modalities, at least for isometric force.

Global data on visual impairment in the year 2002.

PubMed Central

Resnikoff, Serge; Pascolini, Donatella; Etya'ale, Daniel; Kocur, Ivo; Pararajasegaram, Ramachandra; Pokharel, Gopal P.; Mariotti, Silvio P.

2004-01-01

This paper presents estimates of the prevalence of visual impairment and its causes in 2002, based on the best available evidence derived from recent studies. Estimates were determined from data on low vision and blindness as defined in the International statistical classification of diseases, injuries and causes of death, 10th revision. The number of people with visual impairment worldwide in 2002 was in excess of 161 million, of whom about 37 million were blind. The burden of visual impairment is not distributed uniformly throughout the world: the least developed regions carry the largest share. Visual impairment is also unequally distributed across age groups, being largely confined to adults 50 years of age and older. A distribution imbalance is also found with regard to gender throughout the world: females have a significantly higher risk of having visual impairment than males. Notwithstanding the progress in surgical intervention that has been made in many countries over the last few decades, cataract remains the leading cause of visual impairment in all regions of the world, except in the most developed countries. Other major causes of visual impairment are, in order of importance, glaucoma, age-related macular degeneration, diabetic retinopathy and trachoma. PMID:15640920

Global data on visual impairment in the year 2002.

PubMed

Resnikoff, Serge; Pascolini, Donatella; Etya'ale, Daniel; Kocur, Ivo; Pararajasegaram, Ramachandra; Pokharel, Gopal P; Mariotti, Silvio P

2004-11-01

This paper presents estimates of the prevalence of visual impairment and its causes in 2002, based on the best available evidence derived from recent studies. Estimates were determined from data on low vision and blindness as defined in the International statistical classification of diseases, injuries and causes of death, 10th revision. The number of people with visual impairment worldwide in 2002 was in excess of 161 million, of whom about 37 million were blind. The burden of visual impairment is not distributed uniformly throughout the world: the least developed regions carry the largest share. Visual impairment is also unequally distributed across age groups, being largely confined to adults 50 years of age and older. A distribution imbalance is also found with regard to gender throughout the world: females have a significantly higher risk of having visual impairment than males. Notwithstanding the progress in surgical intervention that has been made in many countries over the last few decades, cataract remains the leading cause of visual impairment in all regions of the world, except in the most developed countries. Other major causes of visual impairment are, in order of importance, glaucoma, age-related macular degeneration, diabetic retinopathy and trachoma.

Compensation of corneal oblique astigmatism by internal optics: a theoretical analysis.

PubMed

Liu, Tao; Thibos, Larry N

2017-05-01

Oblique astigmatism is a prominent optical aberration of peripheral vision caused by oblique incidence of rays striking the refracting surfaces of the cornea and crystalline lens. We inquired whether oblique astigmatism from these two sources should be expected, theoretically, to have the same or opposite signs across the visual field at various states of accommodation. Oblique astigmatism was computed across the central visual field for a rotationally-symmetric schematic-eye using optical design software. Accommodative state was varied by altering the apical radius of curvature and separation of the biconvex lens's two aspheric surfaces in a manner consistent with published biometry. Oblique astigmatism was evaluated separately for the whole eye, the cornea, and the isolated lens over a wide range of surface curvatures and asphericity values associated with the accommodating lens. We also computed internal oblique astigmatism by subtracting corneal oblique astigmatism from whole-eye oblique astigmatism. A visual field map of oblique astigmatism for the cornea in the Navarro model follows the classic, textbook description of radially-oriented axes everywhere in the field. Despite large changes in surface properties during accommodation, intrinsic astigmatism of the isolated human lens for collimated light is also radially oriented and nearly independent of accommodation both in theory and in real eyes. However, the magnitude of ocular oblique astigmatism is smaller than that of the cornea alone, indicating partial compensation by the internal optics. This implies internal oblique astigmatism (which includes wavefront propagation from the posterior surface of the cornea to the anterior surface of the lens and intrinsic lens astigmatism) must have tangentially-oriented axes. This non-classical pattern of tangential axes for internal astigmatism was traced to the influence of corneal power on the angles of incidence of rays striking the internal lens. Partial compensation of corneal astigmatism by internal optics is due mainly to the highly converging nature of wavefronts incident upon the lens resulting from corneal refraction. The degree of compensation is quadratically dependent on eccentricity but is expected to diminish as the eye accommodates. Neutralising the cornea by index-matching defeats internal compensation, revealing classical, radially-oriented oblique astigmatism in the isolated lens. © 2017 The Authors Ophthalmic & Physiological Optics © 2017 The College of Optometrists.

Beam-modulation methods in quantitative and flow visualization holographic interferometry

NASA Technical Reports Server (NTRS)

Decker, A.

1986-01-01

This report discusses heterodyne holographic interferometry and time-average holography with a frequency shifted reference beam. Both methods will be used for the measurement and visualization of internal transonic flows, where the target facility is a flutter cascade. The background and experimental requirements for both methods are reviewed. Measurements using heterodyne holographic interferometry are presented. The performance of the laser required for time-average holography of time-varying transonic flows is discussed.

Beam-modulation methods in quantitative and flow-visualization holographic interferometry

NASA Technical Reports Server (NTRS)

Decker, Arthur J.

1986-01-01

Heterodyne holographic interferometry and time-average holography with a frequency shifted reference beam are discussed. Both methods will be used for the measurement and visualization of internal transonic flows where the target facility is a flutter cascade. The background and experimental requirements for both methods are reviewed. Measurements using heterodyne holographic interferometry are presented. The performance of the laser required for time-average holography of time-varying transonic flows is discussed.

Direct Relationship Between Perceptual and Motor Variability

NASA Technical Reports Server (NTRS)

Liston, Dorion B.; Stone, Leland S.

2010-01-01

The time that elapses between stimulus onset and the onset of a saccadic eye movement is longer and more variable than can be explained by neural transmission times and synaptic delays (Carpenter, 1981, in: Eye Movements: Cognition & Visual Perception, Earlbaum). In theory, noise underlying response-time (RT) variability could arise at any point along the sensorimotor cascade, from sensory noise arising Vvithin the early visual processing shared Vvith perception to noise in the motor criterion or commands necessary to trigger movements. These two loci for internal noise can be distinguished empirically; sensory internal noise predicts that response time Vvill correlate Vvith perceived stimulus magnitude whereas motor internal noise predicts no such correlation. Methods. We used the data described by Liston and Stone (2008, JNS 28:13866-13875), in which subjects performed a 2AFC saccadic brightness discrimination task and the perceived brightness of the chosen stimulus was then quantified in a second 21FC perceptual task. Results. We binned each subject's data into quartiles for both signal strength (from dimmest to brightest) and RT (from slowest to fastest) and analyzed the trends in perceived brightness. We found significant effects of both signal strength (as expected) and RT on normalized perceived brightness (both p less than 0.0001, 2-way ANOVA), without significant interaction (p = 0.95, 2-way ANOVA). A plot of normalized perceived brightness versus normalized RT show's that more than half of the variance was shared (r2 = 0.56, P less than 0.0001). To rule out any possibility that some signal-strength related artifact was generating this effect, we ran a control analysis on pairs of trials with repeated presentations of identical stimuli and found that stimuli are perceived to be brighter on trials with faster saccades (p less than 0.001, paired t-test across subjects). Conclusion. These data show that shared early visual internal noise jitters perceived brightness and the saccadic motor output in parallel. While the present correlation could theoretically result, either directly or indirectly, from some low-level brainstem or retinal mechanism (e.g., arousal, pupil size, photoreceptor noise) that influences both visual and oculomotor circuits, this is unlikely given the earlier fin ding that the variability in perceived motion direction and smooth-pursuit motor output is highly correlated (Stone and Krauzlis, 2003, JOV 3:725-736), suggesting that cortical circuits contribute to the shared internal noise.

Earth Science Observations, Analysis and Visualization: Roots in the 60's: Vision for the Next Millennium

NASA Technical Reports Server (NTRS)

Hasler, A. F.

1999-01-01

The Etheater presents visualizations which span the period from the original Suomi/Hasler animations of the first ATS-1 GEO weather satellite images in 1966 ... to the latest 1999 NASA Earth Science Vision for the next 25 years. Hot off the SGI-Onyx Graphics-Supercomputer are NASA's visualizations of Hurricanes Mitch, Georges, Fran and Linda. These storms have been recently featured on the covers of National Geographic, Time, Newsweek and Popular Science. Highlights will be shown from the NASA hurricane visualization resource video tape that has been used repeatedly this season on National and International network TV. Results will be presented from a new paper on automatic wind measurements in Hurricane Luis from 1-min GOES images that appeared in the November BAMS.

Earth Science Observations, Analysis and Visualization: Roots in the 60's - Vision for the Next Millennium

NASA Technical Reports Server (NTRS)

Hasler, A. Fritz; Allen, Jesse

1999-01-01

The Etheater presents visualizations which span the period from the original Suomi/Hasler animations of the first ATS-1 GEO weather satellite images in 1966....... to the latest 1999 NASA Earth Science Vision for the next 25 years. Hot off the SGI-Onyx Graphics-Supercomputer are NASA's visualizations of Hurricanes Mitch, Georges, Fran and Linda. These storms have been recently featured on the covers of National Geographic, Time, Newsweek and Popular Science. Highlights will be shown from the NASA hurricane visualization resource video tape in standard and HDTV that has been used repeatedly this season on National and International network TV. Results will be presented from a new paper on automatic wind measurements in Hurricane Luis from 1-min GOES images that appeared in the November BAMS.

Cerebral venous hypertension and blindness: a reversible complication.

PubMed

Cuadra, Salvador A; Padberg, Frank T; Turbin, Roger E; Farkas, Jeffrey; Frohman, Larry P

2005-10-01

A 57-year-old woman developed blindness during treatment for sarcoidosis-induced end-stage renal disease. An initial renal transplantation failed, and hemoaccess was maintained with multiple central catheters and upper extremity prosthetic arteriovenous grafts. A successful second transplantation eliminated her need for hemodialysis, but a right brachial to internal jugular graft remained patent. Progressive visual loss 2 years after transplantation prompted ophthalmic evaluation which initially revealed unilateral left optic nerve edema and visual loss, ultimately worsening over several months to no light perception in the left eye, 20/60 vision in the right eye, and bilateral papilledema. Arteriography demonstrated cerebral venous hypertension attributed to the functioning hemoaccess graft. Permanent graft occlusion normalized the papilledema, and visual field defects in the right eye and visual acuity returned to 20/20 in the right eye.

Content analysis to detect high stress in oral interviews and text documents

NASA Technical Reports Server (NTRS)

Thirumalainambi, Rajkumar (Inventor); Jorgensen, Charles C. (Inventor)

2012-01-01

A system of interrogation to estimate whether a subject of interrogation is likely experiencing high stress, emotional volatility and/or internal conflict in the subject's responses to an interviewer's questions. The system applies one or more of four procedures, a first statistical analysis, a second statistical analysis, a third analysis and a heat map analysis, to identify one or more documents containing the subject's responses for which further examination is recommended. Words in the documents are characterized in terms of dimensions representing different classes of emotions and states of mind, in which the subject's responses that manifest high stress, emotional volatility and/or internal conflict are identified. A heat map visually displays the dimensions manifested by the subject's responses in different colors, textures, geometric shapes or other visually distinguishable indicia.

A quantitative visual dashboard to explore exposures to ...

EPA Pesticide Factsheets

The Exposure Prioritization (Ex Priori) model features a simplified, quantitative visual dashboard to explore exposures across chemical space. Diverse data streams are integrated within the interface such that different exposure scenarios for “individual,” “population,” or “professional” time-use profiles can be interchanged to tailor exposure and quantitatively explore multi-chemical signatures of exposure, internalized dose (uptake), body burden, and elimination. Ex Priori will quantitatively extrapolate single-point estimates of both exposure and internal dose for multiple exposure scenarios, factors, products, and pathways. Currently, EPA is investigating its usefulness in life cycle analysis, insofar as its ability to enhance exposure factors used in calculating characterization factors for human health. Presented at 2016 Annual ISES Meeting held in Utrecht, The Netherlands, from 9-13 October 2016.

Effects of Spaceflight on Venous and Arterial Compliance

NASA Technical Reports Server (NTRS)

Platts, S. H.; Pibeiro, L. C.; Laurie, S. S.; Lee, S. M. C.; Martin, D. S.; Ploutz-Snyder, R.; Stenger, M. B.

2016-01-01

The visual impairment and intracranial pressure (VIIP) syndrome is a spaceflight-associated medical condition consisting of a constellation of symptoms affecting less than 70% of American astronauts who have flown International Space Station (ISS) missions. VIIP is defined primarily by visual acuity deficits and anatomical changes to eye structures and is hypothesized to be related to elevated intracranial pressure secondary to spaceflight-induced cephalad fluid shifts, although other space flight factors (e.g., diet, environmental factors) may contribute. Loss of visual acuity could be a significant threat to crew health and performance during and after an exploration mission and may have implications for years postflight.

Precortical dysfunction of spatial and temporal visual processing in migraine.

PubMed Central

Coleston, D M; Chronicle, E; Ruddock, K H; Kennard, C

1994-01-01

This paper examines spatial and temporal processing in migraineurs (diagnosed according to International Headache Society criteria, 1988), using psychophysical tests that measure spatial and temporal responses. These tests are considered to specifically assess precortical mechanisms. Results suggest precortical dysfunction for processing of spatial and temporal visual stimuli in 11 migraineurs with visual aura and 13 migraineurs without aura; the two groups could not be distinguished. As precortical dysfunction seems to be common to both groups of patients, it is suggested that symptoms that are experienced by both groups, such as blurring of vision and photophobia, may have their basis at a precortical level. PMID:7931382

OH Vision Test

NASA Image and Video Library

2014-06-02

ISS040-E-006107 (2 June 2014) --- NASA astronaut Steve Swanson, Expedition 40 commander, performs a visual exam using an eye chart (out of frame) in the Destiny laboratory of the International Space Station.

Electrophysiological evidence for parts and wholes in visual face memory.

PubMed

Towler, John; Eimer, Martin

2016-10-01

It is often assumed that upright faces are represented in a holistic fashion, while representations of inverted faces are essentially part-based. To assess this hypothesis, we recorded event-related potentials (ERPs) during a sequential face identity matching task where successively presented pairs of upright or inverted faces were either identical or differed with respect to their internal features, their external features, or both. Participants' task was to report on each trial whether the face pair was identical or different. To track the activation of visual face memory representations, we measured N250r components that emerge over posterior face-selective regions during the activation of visual face memory representations by a successful identity match. N250r components to full identity repetitions were smaller and emerged later for inverted as compared to upright faces, demonstrating that image inversion impairs face identity matching processes. For upright faces, N250r components were also elicited by partial repetitions of external or internal features, which suggest that the underlying identity matching processes are not exclusively based on non-decomposable holistic representations. However, the N250r to full identity repetitions was super-additive (i.e., larger than the sum of the two N250r components to partial repetitions of external or internal features) for upright faces, demonstrating that holistic representations were involved in identity matching processes. For inverted faces, N250r components to full and partial identity repetitions were strictly additive, indicating that the identity matching of external and internal features operated in an entirely part-based fashion. These results provide new electrophysiological evidence for qualitative differences between representations of upright and inverted faces in the occipital-temporal face processing system. Copyright © 2016 Elsevier Ltd. All rights reserved.

Internal curvature signal and noise in low- and high-level vision

PubMed Central

Grabowecky, Marcia; Kim, Yee Joon; Suzuki, Satoru

2011-01-01

How does internal processing contribute to visual pattern perception? By modeling visual search performance, we estimated internal signal and noise relevant to perception of curvature, a basic feature important for encoding of three-dimensional surfaces and objects. We used isolated, sparse, crowded, and face contexts to determine how internal curvature signal and noise depended on image crowding, lateral feature interactions, and level of pattern processing. Observers reported the curvature of a briefly flashed segment, which was presented alone (without lateral interaction) or among multiple straight segments (with lateral interaction). Each segment was presented with no context (engaging low-to-intermediate-level curvature processing), embedded within a face context as the mouth (engaging high-level face processing), or embedded within an inverted-scrambled-face context as a control for crowding. Using a simple, biologically plausible model of curvature perception, we estimated internal curvature signal and noise as the mean and standard deviation, respectively, of the Gaussian-distributed population activity of local curvature-tuned channels that best simulated behavioral curvature responses. Internal noise was increased by crowding but not by face context (irrespective of lateral interactions), suggesting prevention of noise accumulation in high-level pattern processing. In contrast, internal curvature signal was unaffected by crowding but modulated by lateral interactions. Lateral interactions (with straight segments) increased curvature signal when no contextual elements were added, but equivalent interactions reduced curvature signal when each segment was presented within a face. These opposing effects of lateral interactions are consistent with the phenomena of local-feature contrast in low-level processing and global-feature averaging in high-level processing. PMID:21209356

Illusory Motion Reproduced by Deep Neural Networks Trained for Prediction

PubMed Central

Watanabe, Eiji; Kitaoka, Akiyoshi; Sakamoto, Kiwako; Yasugi, Masaki; Tanaka, Kenta

2018-01-01

The cerebral cortex predicts visual motion to adapt human behavior to surrounding objects moving in real time. Although the underlying mechanisms are still unknown, predictive coding is one of the leading theories. Predictive coding assumes that the brain's internal models (which are acquired through learning) predict the visual world at all times and that errors between the prediction and the actual sensory input further refine the internal models. In the past year, deep neural networks based on predictive coding were reported for a video prediction machine called PredNet. If the theory substantially reproduces the visual information processing of the cerebral cortex, then PredNet can be expected to represent the human visual perception of motion. In this study, PredNet was trained with natural scene videos of the self-motion of the viewer, and the motion prediction ability of the obtained computer model was verified using unlearned videos. We found that the computer model accurately predicted the magnitude and direction of motion of a rotating propeller in unlearned videos. Surprisingly, it also represented the rotational motion for illusion images that were not moving physically, much like human visual perception. While the trained network accurately reproduced the direction of illusory rotation, it did not detect motion components in negative control pictures wherein people do not perceive illusory motion. This research supports the exciting idea that the mechanism assumed by the predictive coding theory is one of basis of motion illusion generation. Using sensory illusions as indicators of human perception, deep neural networks are expected to contribute significantly to the development of brain research. PMID:29599739

Illusory Motion Reproduced by Deep Neural Networks Trained for Prediction.

PubMed

Watanabe, Eiji; Kitaoka, Akiyoshi; Sakamoto, Kiwako; Yasugi, Masaki; Tanaka, Kenta

2018-01-01

The cerebral cortex predicts visual motion to adapt human behavior to surrounding objects moving in real time. Although the underlying mechanisms are still unknown, predictive coding is one of the leading theories. Predictive coding assumes that the brain's internal models (which are acquired through learning) predict the visual world at all times and that errors between the prediction and the actual sensory input further refine the internal models. In the past year, deep neural networks based on predictive coding were reported for a video prediction machine called PredNet. If the theory substantially reproduces the visual information processing of the cerebral cortex, then PredNet can be expected to represent the human visual perception of motion. In this study, PredNet was trained with natural scene videos of the self-motion of the viewer, and the motion prediction ability of the obtained computer model was verified using unlearned videos. We found that the computer model accurately predicted the magnitude and direction of motion of a rotating propeller in unlearned videos. Surprisingly, it also represented the rotational motion for illusion images that were not moving physically, much like human visual perception. While the trained network accurately reproduced the direction of illusory rotation, it did not detect motion components in negative control pictures wherein people do not perceive illusory motion. This research supports the exciting idea that the mechanism assumed by the predictive coding theory is one of basis of motion illusion generation. Using sensory illusions as indicators of human perception, deep neural networks are expected to contribute significantly to the development of brain research.

Sensitivity to audio-visual synchrony and its relation to language abilities in children with and without ASD.

PubMed

Righi, Giulia; Tenenbaum, Elena J; McCormick, Carolyn; Blossom, Megan; Amso, Dima; Sheinkopf, Stephen J

2018-04-01

Autism Spectrum Disorder (ASD) is often accompanied by deficits in speech and language processing. Speech processing relies heavily on the integration of auditory and visual information, and it has been suggested that the ability to detect correspondence between auditory and visual signals helps to lay the foundation for successful language development. The goal of the present study was to examine whether young children with ASD show reduced sensitivity to temporal asynchronies in a speech processing task when compared to typically developing controls, and to examine how this sensitivity might relate to language proficiency. Using automated eye tracking methods, we found that children with ASD failed to demonstrate sensitivity to asynchronies of 0.3s, 0.6s, or 1.0s between a video of a woman speaking and the corresponding audio track. In contrast, typically developing children who were language-matched to the ASD group, were sensitive to both 0.6s and 1.0s asynchronies. We also demonstrated that individual differences in sensitivity to audiovisual asynchronies and individual differences in orientation to relevant facial features were both correlated with scores on a standardized measure of language abilities. Results are discussed in the context of attention to visual language and audio-visual processing as potential precursors to language impairment in ASD. Autism Res 2018, 11: 645-653. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. Speech processing relies heavily on the integration of auditory and visual information, and it has been suggested that the ability to detect correspondence between auditory and visual signals helps to lay the foundation for successful language development. The goal of the present study was to explore whether children with ASD process audio-visual synchrony in ways comparable to their typically developing peers, and the relationship between preference for synchrony and language ability. Results showed that there are differences in attention to audiovisual synchrony between typically developing children and children with ASD. Preference for synchrony was related to the language abilities of children across groups. © 2018 International Society for Autism Research, Wiley Periodicals, Inc.

Long-axis view for ultrasound-guided central venous catheter placement via the internal jugular vein.

PubMed

Mahan, Angel F; McEvoy, Matthew D; Gravenstein, Nikolaus

2016-04-01

In modern practice, real-time ultrasound guidance is commonly employed for the placement of internal jugular vein catheters. With a new tool, such as ultrasound, comes the opportunity to refine and further optimize the ultrasound view during jugular vein catheterization. We describe jugular vein access techniques and use the long-axis view as an alternative to the commonly employed short-axis cross-section view for internal jugular vein access and cannulation. The long-axis ultrasound-guided internal jugular vein approach for internal jugular vein cannulation is a useful alternative technique that can provide better needle tip and guidewire visualization than the more traditional short-axis ultrasound view.

Velocity and Structure Estimation of a Moving Object Using a Moving Monocular Camera

DTIC Science & Technology

2006-01-01

map the Euclidean position of static landmarks or visual features in the environment . Recent applications of this technique include aerial...From Motion in a Piecewise Planar Environment ,” International Journal of Pattern Recognition and Artificial Intelligence, Vol. 2, No. 3, pp. 485-508...1988. [9] J. M. Ferryman, S. J. Maybank , and A. D. Worrall, “Visual Surveil- lance for Moving Vehicles,” Intl. Journal of Computer Vision, Vol. 37, No

Kopra

NASA Image and Video Library

2016-03-16

ISS047e010094 (03/16/2016) --- Expedition 47 Commander Tim Kopra of NASA participates in the Ocular Health investigation aboard the International Space Station. The study seeks to help researchers better understand microgravity-induced visual impairment and changes believed to arise from elevated intracranial pressure. These tests will help characterize how living in microgravity can affect the visual, vascular and central nervous system. The investigation will also measure how long it takes for astronauts to return to normal after they return to Earth.

International Symposium on Visually Handicapped Infants and Young Children: Birth to Seven (2nd, Aruba, 1987). "The First Steps." Proceedings = Simpasio Internacional sobre Ninos Visualmente Deficientes de Nacimiento hasta Siete Anos (2nd, Aruba, 1987). "Los Primeros Pasos."

ERIC Educational Resources Information Center

Palmer, Lillian, Ed.; And Others

This symposium focused on the special needs of visually handicapped infants and young children. Texts of 48 papers are presented, including keynote addresses by W. Aubrey Webson ("The First Steps") and Heather Hewitt ("First Steps--Parenting, Prevention and Programming"). Regional reports are provided for Japan, Bangladesh, the…

The Movement Imagery Questionnaire-Revised, Second Edition (MIQ-RS) Is a Reliable and Valid Tool for Evaluating Motor Imagery in Stroke Populations

PubMed Central

Butler, Andrew J.; Cazeaux, Jennifer; Fidler, Anna; Jansen, Jessica; Lefkove, Nehama; Gregg, Melanie; Hall, Craig; Easley, Kirk A.; Shenvi, Neeta; Wolf, Steven L.

2012-01-01

Mental imagery can improve motor performance in stroke populations when combined with physical therapy. Valid and reliable instruments to evaluate the imagery ability of stroke survivors are needed to maximize the benefits of mental imagery therapy. The purposes of this study were to: examine and compare the test-retest intra-rate reliability of the Movement Imagery Questionnaire-Revised, Second Edition (MIQ-RS) in stroke survivors and able-bodied controls, examine internal consistency of the visual and kinesthetic items of the MIQ-RS, determine if the MIQ-RS includes both the visual and kinesthetic dimensions of mental imagery, correlate impairment and motor imagery scores, and investigate the criterion validity of the MIQ-RS in stroke survivors by comparing the results to the KVIQ-10. Test-retest analysis indicated good levels of reliability (ICC range: .83–.99) and internal consistency (Cronbach α: .95–.98) of the visual and kinesthetic subscales in both groups. The two-factor structure of the MIQ-RS was supported by factor analysis, with the visual and kinesthetic components accounting for 88.6% and 83.4% of the total variance in the able-bodied and stroke groups, respectively. The MIQ-RS is a valid and reliable instrument in the stroke population examined and able-bodied populations and therefore useful as an outcome measure for motor imagery ability. PMID:22474504

Visual detail about the body modulates tactile localisation biases.

PubMed

Margolis, Aaron N; Longo, Matthew R

2015-02-01

The localisation of tactile stimuli requires the integration of visual and somatosensory inputs within an internal representation of the body surface and is prone to consistent bias. Joints may play a role in segmenting such internal body representations, and may therefore influence tactile localisation biases, although the nature of this influence remains unclear. Here, we investigate the relationship between conceptual knowledge of joint locations and tactile localisation biases on the hand. In one task, participants localised tactile stimuli applied to the dorsum of their hand. A distal localisation bias was observed in all participants, consistent with previous results. We also manipulated the availability of visual information during this task, to determine whether the absence of this information could account for the distal bias observed here and by Mancini et al. (Neuropsychologia 49:1194-1201, 2011). The observed distal bias increased in magnitude when visual information was restricted, without a corresponding decrease in precision. In a separate task, the same participants indicated, from memory, knuckle locations on a silhouette image of their hand. Analogous distal biases were also seen in the knuckle localisation task. The accuracy of conceptual joint knowledge was not correlated with tactile localisation bias magnitude, although a similarity in observed bias direction suggests that both tasks may rely on a common, higher-order body representation. These results also suggest that distortions of conceptual body representation may be more common in healthy individuals than previously thought.

Source memory errors in schizophrenia, hallucinations and negative symptoms: a synthesis of research findings.

PubMed

Brébion, G; Ohlsen, R I; Bressan, R A; David, A S

2012-12-01

Previous research has shown associations between source memory errors and hallucinations in patients with schizophrenia. We bring together here findings from a broad memory investigation to specify better the type of source memory failure that is associated with auditory and visual hallucinations. Forty-one patients with schizophrenia and 43 healthy participants underwent a memory task involving recall and recognition of lists of words, recognition of pictures, memory for temporal and spatial context of presentation of the stimuli, and remembering whether target items were presented as words or pictures. False recognition of words and pictures was associated with hallucination scores. The extra-list intrusions in free recall were associated with verbal hallucinations whereas the intra-list intrusions were associated with a global hallucination score. Errors in discriminating the temporal context of word presentation and the spatial context of picture presentation were associated with auditory hallucinations. The tendency to remember verbal labels of items as pictures of these items was associated with visual hallucinations. Several memory errors were also inversely associated with affective flattening and anhedonia. Verbal and visual hallucinations are associated with confusion between internal verbal thoughts or internal visual images and perception. In addition, auditory hallucinations are associated with failure to process or remember the context of presentation of the events. Certain negative symptoms have an opposite effect on memory errors.

Applying microCT and 3D visualization to Jurassic silicified conifer seed cones: A virtual advantage over thin-sectioning.

PubMed

Gee, Carole T

2013-11-01

As an alternative to conventional thin-sectioning, which destroys fossil material, high-resolution X-ray computed tomography (also called microtomography or microCT) integrated with scientific visualization, three-dimensional (3D) image segmentation, size analysis, and computer animation is explored as a nondestructive method of imaging the internal anatomy of 150-million-year-old conifer seed cones from the Late Jurassic Morrison Formation, USA, and of recent and other fossil cones. • MicroCT was carried out on cones using a General Electric phoenix v|tome|x s 240D, and resulting projections were processed with visualization software to produce image stacks of serial single sections for two-dimensional (2D) visualization, 3D segmented reconstructions with targeted structures in color, and computer animations. • If preserved in differing densities, microCT produced images of internal fossil tissues that showed important characters such as seed phyllotaxy or number of seeds per cone scale. Color segmentation of deeply embedded seeds highlighted the arrangement of seeds in spirals. MicroCT of recent cones was even more effective. • This is the first paper on microCT integrated with 3D segmentation and computer animation applied to silicified seed cones, which resulted in excellent 2D serial sections and segmented 3D reconstructions, revealing features requisite to cone identification and understanding of strobilus construction.

Internal Limiting Membrane Peeling to Prevent Post-vitrectomy Epiretinal Membrane Development in Retinal Detachment.

PubMed

Akiyama, Kunihiko; Fujinami, Kaoru; Watanabe, Ken; Tsunoda, Kazushige; Noda, Toru

2016-11-01

To determine the efficacy of internal limiting membrane (ILM) peeling during vitrectomy for rhegmatogenous retinal detachment (RRD) regarding post-vitrectomy epiretinal membrane (ERM) development and visual outcomes. Retrospective, interventional, comparative case series. Setting: Institutional. One hundred and two consecutive eyes with RRD treated with vitrectomy and followed for at least 6 months. ILM was peeled without using dye such as indocyanine green (ICG). Observational Procedures: Patients were divided into 2 groups based on postoperative ERM development: Group 1, 81 eyes without ERM formation; Group 2, 21 eyes with ERM development. Patients also were divided into 2 subgroups: those with and without ILM peeling (58 and 44 eyes, respectively). Statistical analyses were performed between the 2 groups with/without ERM formation and between the 2 subgroups with/without ILM peeling for 5 preoperative factors including foveal involvement of the RRD, 4 intraoperative factors including ILM peeling, baseline best-corrected visual acuity (BCVA), and final BCVA. An association of ILM peeling with ERM prevention and the influence of ILM peeling on visual outcomes. ILM peeling was significantly (P < .001) associated with ERM prevention. There was no significant difference in the final BCVA between subgroups with and without ILM peeling. ILM peeling without ICG staining during the initial vitrectomy for RRDs may prevent postoperative ERM formation with favorable visual outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

[Optical coherence tomography and microperimetry after internal limiting membrane peeling for epiretinal membrane].

PubMed

Grimbert, P; Lebreton, O; Weber, M

2014-06-01

To evaluate the anatomical and functional consequences of internal limiting membrane (ILM) peeling in epiretinal membrane (ERM) surgery. Retrospective single-center study including consecutive patients operated on for idiopathic ERM. The integrity of the ILM was assessed by ILM Blue® staining after removal of the ERM: either the peeling was spontaneous (group 1) or a complementary peeling was required (group 2). Pre- and post-operatively (1 and 6 months), all patients were analyzed using visual acuity, SD-OCT (Spectralis HRA OCT, Heidelberg, Germany) and microperimetry (OPKO/OTI, Miami, USA). Twenty-one eyes of 21 patients were included: 12 "active ILM peelings" and 9 "spontaneous peelings". In both groups, visual acuity increased significantly after surgery. Microperimetry revealed more microscotomata at 1 and 6 months for active peeling (P<0.05). Their location corresponded more often to the site where the ERM or ILM was grasped, based on surgical videos (P<0.05), and with the appearance of inner retinal defects using en face OCT. ILM peeling is frequently performed to reduce ERM recurrence. Despite lack of effect on visual acuity, active ILM peeling increases the incidence of microscotomas related to the site where the ERM or ILM is grasped. Active ILM peeling may be responsible for postoperative visual discomfort related to microscopic trauma during peeling. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Age-Related Differences in Cortical and Subcortical Activities during Observation and Motor Imagery of Dynamic Postural Tasks: An fMRI Study.

PubMed

Mouthon, A; Ruffieux, J; Mouthon, M; Hoogewoud, H-M; Annoni, J-M; Taube, W

2018-01-01

Age-related changes in brain activation other than in the primary motor cortex are not well known with respect to dynamic balance control. Therefore, the current study aimed to explore age-related differences in the control of static and dynamic postural tasks using fMRI during mental simulation of balance tasks. For this purpose, 16 elderly (72 ± 5 years) and 16 young adults (27 ± 5 years) were asked to mentally simulate a static and a dynamic balance task by motor imagery (MI), action observation (AO), or the combination of AO and MI (AO + MI). Age-related differences were detected in the form of larger brain activations in elderly compared to young participants, especially in the challenging dynamic task when applying AO + MI. Interestingly, when MI (no visual input) was contrasted to AO (visual input), elderly participants revealed deactivation of subcortical areas. The finding that the elderly demonstrated overactivation in mostly cortical areas in challenging postural conditions with visual input (AO + MI and AO) but deactivation in subcortical areas during MI (no vision) may indicate that elderly individuals allocate more cortical resources to the internal representation of dynamic postural tasks. Furthermore, it might be assumed that they depend more strongly on visual input to activate subcortical internal representations.

Age-Related Differences in Cortical and Subcortical Activities during Observation and Motor Imagery of Dynamic Postural Tasks: An fMRI Study

PubMed Central

Ruffieux, J.; Mouthon, M.; Hoogewoud, H.-M.; Taube, W.

2018-01-01

Age-related changes in brain activation other than in the primary motor cortex are not well known with respect to dynamic balance control. Therefore, the current study aimed to explore age-related differences in the control of static and dynamic postural tasks using fMRI during mental simulation of balance tasks. For this purpose, 16 elderly (72 ± 5 years) and 16 young adults (27 ± 5 years) were asked to mentally simulate a static and a dynamic balance task by motor imagery (MI), action observation (AO), or the combination of AO and MI (AO + MI). Age-related differences were detected in the form of larger brain activations in elderly compared to young participants, especially in the challenging dynamic task when applying AO + MI. Interestingly, when MI (no visual input) was contrasted to AO (visual input), elderly participants revealed deactivation of subcortical areas. The finding that the elderly demonstrated overactivation in mostly cortical areas in challenging postural conditions with visual input (AO + MI and AO) but deactivation in subcortical areas during MI (no vision) may indicate that elderly individuals allocate more cortical resources to the internal representation of dynamic postural tasks. Furthermore, it might be assumed that they depend more strongly on visual input to activate subcortical internal representations. PMID:29675037

Alcohol marketing in televised international football: frequency analysis.

PubMed

Adams, Jean; Coleman, James; White, Martin

2014-05-20

Alcohol marketing includes sponsorship of individuals, organisations and sporting events. Football (soccer) is one of the most popular spectator sports worldwide. No previous studies have quantified the frequency of alcohol marketing in a high profile international football tournament. The aims were to determine: the frequency and nature of visual references to alcohol in a representative sample of EURO2012 matches broadcast in the UK; and if frequency or nature varied between matches broadcast on public service and commercial channels, or between matches that did and did not feature England. Eight matches selected by stratified random sampling were recorded. All visual references to alcohol were identified using a tool with high inter-rater reliability. 1846 visual references to alcohol were identified over 1487 minutes of broadcast--an average of 1.24 references per minute. The mean number of references per minute was higher in matches that did vs did not feature England (p = 0.004), but did not differ between matches broadcast on public service vs commercial channels (p = 0.92). The frequency of visual references to alcohol was universally high and higher in matches featuring the only UK home team--England--suggesting that there may be targeting of particularly highly viewed matches. References were embedded in broadcasts, and not particular to commercial channels including paid-for advertising. New UK codes-of-conduct on alcohol marketing at sporting events will not reduce the level of marketing reported here.

Assessment of cataract surgical outcomes in settings where follow-up is poor: PRECOG, a multicentre observational study.

PubMed

Congdon, Nathan; Yan, Xixi; Lansingh, Van; Sisay, Alemayehu; Müller, Andreas; Chan, Ving; Jin, Ling; Meltzer, Mirjam E; Karumanchi, Sasipriya M; Guan, Chunhong; Vuong, Quy; Rivera, Nelson; McCleod-Omawale, Joan; He, Mingguang

2013-07-01

Poor follow-up after cataract surgery in developing countries makes assessment of operative quality uncertain. We aimed to assess two strategies to measure visual outcome: recording the visual acuity of all patients 3 or fewer days postoperatively (early postoperative assessment), and recording that of only those patients who returned for the final follow-up examination after 40 or more days without additional prompting. Each of 40 centres in ten countries in Asia, Africa, and Latin America recruited 40-120 consecutive surgical cataract patients. Operative-eye best-corrected visual acuity and uncorrected visual acuity were recorded before surgery, 3 or fewer days postoperatively, and 40 or more days postoperatively. Clinics logged whether each patient had returned for the final follow-up examination without additional prompting, had to be actively encouraged to return, or had to be examined at home. Visual outcome for each centre was defined as the proportion of patients with uncorrected visual acuity of 6/18 or better minus the proportion with uncorrected visual acuity of 6/60 or worse, and was calculated for each participating hospital with results from the early assessment of all patients and the late assessment of only those returning unprompted, with results from the final follow-up assessment for all patients used as the standard. Of 3708 participants, 3441 (93%) had final follow-up vision data recorded 40 or more days after surgery, 1831 of whom (51% of the 3581 total participants for whom mode of follow-up was recorded) had returned to the clinic without additional prompting. Visual outcome by hospital from early postoperative and final follow-up assessment for all patients were highly correlated (Spearman's rs=0·74, p<0·0001). Visual outcome from final follow-up assessment for all patients and for only those who returned without additional prompting were also highly correlated (rs=0·86, p<0·0001), even for the 17 hospitals with unprompted return rates of less than 50% (rs=0·71, p=0·002). When we divided hospitals into top 25%, middle 50%, and bottom 25% by visual outcome, classification based on final follow-up assessment for all patients was the same as that based on early postoperative assessment for 27 (68%) of 40 centres, and the same as that based on data from patients who returned without additional prompting in 31 (84%) of 37 centres. Use of glasses to optimise vision at the time of the early and late examinations did not further improve the correlations. Early vision assessment for all patients and follow-up assessment only for patients who return to the clinic without prompting are valid measures of operative quality in settings where follow-up is poor. ORBIS International, Fred Hollows Foundation, Helen Keller International, International Association for the Prevention of Blindness Latin American Office, Aravind Eye Care System. Copyright © 2013 Congdon et al. Open Access article distributed under the terms of CC BY. Published by .. All rights reserved.

NASA/NOAA Earth Science Electronic Theater 1999. Earth Science Observations, Analysis and Visualization: Roots in the 60s: Vision for the Next Millennium

NASA Technical Reports Server (NTRS)

Hasler, Fritz

1999-01-01

The Etheater presents visualizations which span the period from the original Suomi/Hasler animations of the first ATS-1 GEO weather satellite images in 1966 ....... to the latest 1999 NASA Earth Science Vision for the next 25 years. Hot off the SGI-Onyx Graphics-Supercomputer are NASA's visualizations of Hurricanes Mitch, Georges, Fran and Linda. These storms have been recently featured on the covers of National Geographic, Time, Newsweek and Popular Science. Highlights will be shown from the NASA hurricane visualization resource video tape in standard and HDTV that has been used repeatedly this season on National and International network TV. Results will be presented from a new paper on automatic wind measurements in Hurricane Luis from 1-min GOES images that appeared in the November BAMS.

Visual perception and interception of falling objects: a review of evidence for an internal model of gravity.

PubMed

Zago, Myrka; Lacquaniti, Francesco

2005-09-01

Prevailing views on how we time the interception of a moving object assume that the visual inputs are informationally sufficient to estimate the time-to-contact from the object's kinematics. However, there are limitations in the visual system that raise questions about the general validity of these theories. Most notably, vision is poorly sensitive to arbitrary accelerations. How then does the brain deal with the motion of objects accelerated by Earth's gravity? Here we review evidence in favor of the view that the brain makes the best estimate about target motion based on visually measured kinematics and an a priori guess about the causes of motion. According to this theory, a predictive model is used to extrapolate time-to-contact from the expected kinetics in the Earth's gravitational field.

High-intensity erotic visual stimuli de-activate the primary visual cortex in women.

PubMed

Huynh, Hieu K; Beers, Caroline; Willemsen, Antoon; Lont, Erna; Laan, Ellen; Dierckx, Rudi; Jansen, Monique; Sand, Michael; Weijmar Schultz, Willibrord; Holstege, Gert

2012-06-01

The primary visual cortex, Brodmann's area (BA 17), plays a vital role in basic survival mechanisms in humans. In most neuro-imaging studies in which the volunteers have to watch pictures or movies, the primary visual cortex is similarly activated independent of the content of the pictures or movies. However, in case the volunteers perform demanding non-visual tasks, the primary visual cortex becomes de-activated, although the amount of incoming visual sensory information is the same. Do low- and high-intensity erotic movies, compared to neutral movies, produce similar de-activation of the primary visual cortex? Brain activation/de-activation was studied by Positron Emission Tomography scanning of the brains of 12 healthy heterosexual premenopausal women, aged 18-47, who watched neutral, low- and high-intensity erotic film segments. We measured differences in regional cerebral blood flow (rCBF) in the primary visual cortex during watching neutral, low-intensity erotic, and high-intensity erotic film segments. Watching high-intensity erotic, but not low-intensity erotic movies, compared to neutral movies resulted in strong de-activation of the primary (BA 17) and adjoining parts of the secondary visual cortex. The strong de-activation during watching high-intensity erotic film might represent compensation for the increased blood supply in the brain regions involved in sexual arousal, also because high-intensity erotic movies do not require precise scanning of the visual field, because the impact is clear to the observer. © 2012 International Society for Sexual Medicine.

Splitting attention across the two visual fields in visual short-term memory.

PubMed

Delvenne, Jean-Francois; Holt, Jessica L

2012-02-01

Humans have the ability to attentionally select the most relevant visual information from their extrapersonal world and to retain it in a temporary buffer, known as visual short-term memory (VSTM). Research suggests that at least two non-contiguous items can be selected simultaneously when they are distributed across the two visual hemifields. In two experiments, we show that attention can also be split between the left and right sides of internal representations held in VSTM. Participants were asked to remember several colors, while cues presented during the delay instructed them to orient their attention to a subset of memorized colors. Experiment 1 revealed that orienting attention to one or two colors strengthened equally participants' memory for those colors, but only when they were from separate hemifields. Experiment 2 showed that in the absence of attentional cues the distribution of the items in the visual field per se had no effect on memory. These findings strongly suggest the existence of independent attentional resources in the two hemifields for selecting and/or consolidating information in VSTM. Copyright © 2011 Elsevier B.V. All rights reserved.

Child behavior check list and Korean personality inventory for children with functional visual loss.

PubMed

Kyung, Sung Eun; Lee, Sang Mi; Lim, Myung Ho

2014-08-01

To investigate the clinical psychiatric characteristics of children with the main complaint of functional visual loss, their behavior and personality were evaluated by the means of the Korean child behavior check list (K-CBCL), and the Korean personality inventory for children (KPI-C). The evaluation was carried out by the K-CBCL and the KPI-C, the domestically standardized tools, with 20 child subjects suspected of functional visual loss, among the patients who visited our hospital, between August, 2005 and December, 2012. The control group included 160 children in general schools of the same region. The 20 patients whose main complaint was functional visual loss were diagnosed as having a functional visual disorder. The child patient group showed a higher score for the K-CBCL and KPI-C sub-scales of somatic complaints, social problems, aggressive behavior, internalizing problems, externalizing problems, total behavioral problems, somatization and hyperactivity, than that of the control group. The results of the K-CBCL and KPI-C tests among children with functional visual loss, were significantly different from those of the normal control group. This result suggested that psychological factors may influence children with a main complaint of functional visual loss.

Crossmodal interactions during non-linguistic auditory processing in cochlear-implanted deaf patients.

PubMed

Barone, Pascal; Chambaudie, Laure; Strelnikov, Kuzma; Fraysse, Bernard; Marx, Mathieu; Belin, Pascal; Deguine, Olivier

2016-10-01

Due to signal distortion, speech comprehension in cochlear-implanted (CI) patients relies strongly on visual information, a compensatory strategy supported by important cortical crossmodal reorganisations. Though crossmodal interactions are evident for speech processing, it is unclear whether a visual influence is observed in CI patients during non-linguistic visual-auditory processing, such as face-voice interactions, which are important in social communication. We analyse and compare visual-auditory interactions in CI patients and normal-hearing subjects (NHS) at equivalent auditory performance levels. Proficient CI patients and NHS performed a voice-gender categorisation in the visual-auditory modality from a morphing-generated voice continuum between male and female speakers, while ignoring the presentation of a male or female visual face. Our data show that during the face-voice interaction, CI deaf patients are strongly influenced by visual information when performing an auditory gender categorisation task, in spite of maximum recovery of auditory speech. No such effect is observed in NHS, even in situations of CI simulation. Our hypothesis is that the functional crossmodal reorganisation that occurs in deafness could influence nonverbal processing, such as face-voice interaction; this is important for patient internal supramodal representation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Felder-Soloman's Index of Learning Styles: internal consistency, temporal stability, and factor structure.

PubMed

Hosford, Charles C; Siders, William A

2010-10-01

Strategies to facilitate learning include using knowledge of students' learning style preferences to inform students and their teachers. Aims of this study were to evaluate the factor structure, internal consistency, and temporal stability of medical student responses to the Index of Learning Styles (ILS) and determine its appropriateness as an instrument for medical education. The ILS assesses preferences on four dimensions: sensing/intuitive information perceiving, visual/verbal information receiving, active/reflective information processing, and sequential/global information understanding. Students entering the 2002-2007 classes completed the ILS; some completed the ILS again after 2 and 4 years. Analyses of responses supported the ILS's intended structure and moderate reliability. Students had moderate preferences for sensing and visual learning. This study provides evidence supporting the appropriateness of the ILS for assessing learning style preferences in medical students.

Analysis of International Space Station Vehicle Materials Exposed on Materials International Space Station Experiment from 2001 to 2011

NASA Technical Reports Server (NTRS)

Finckenor, M. M.; Golden, J. L.; Kravchenko, M.

2013-01-01

Since August 2001, the Materials on International Space Station Experiment (MISSE) has provided data on a variety of materials and spacecraft components, including samples chosen to provide sustaining engineering and life extension data for the International Space Station vehicle itself. This Technical Publication is by no means a complete set of MISSE data but does provide changes in solar absorptance, infrared emittance, and visual appearance due to atomic oxygen, ultraviolet radiation, and thermal cycling in vacuum. Conversion coatings, anodizes, thermal control coatings with organic and inorganic binders, multilayer insulation components, optical materials, and part markings are discussed.

Compensatory shifts in visual perception are associated with hallucinations in Lewy body disorders.

PubMed

Bowman, Alan Robert; Bruce, Vicki; Colbourn, Christopher J; Collerton, Daniel

2017-01-01

Visual hallucinations are a common, distressing, and disabling symptom of Lewy body and other diseases. Current models suggest that interactions in internal cognitive processes generate hallucinations. However, these neglect external factors. Pareidolic illusions are an experimental analogue of hallucinations. They are easily induced in Lewy body disease, have similar content to spontaneous hallucinations, and respond to cholinesterase inhibitors in the same way. We used a primed pareidolia task with hallucinating participants with Lewy body disorders (n = 16), non-hallucinating participants with Lewy body disorders (n = 19), and healthy controls (n = 20). Participants were presented with visual "noise" that sometimes contained degraded visual objects and were required to indicate what they saw. Some perceptions were cued in advance by a visual prime. Results showed that hallucinating participants were impaired in discerning visual signals from noise, with a relaxed criterion threshold for perception compared to both other groups. After the presentation of a visual prime, the criterion was comparable to the other groups. The results suggest that participants with hallucinations compensate for perceptual deficits by relaxing perceptual criteria, at a cost of seeing things that are not there, and that visual cues regularize perception. This latter finding may provide a mechanism for understanding the interaction between environments and hallucinations.

Could visual neglect induce amblyopia?

PubMed

Bier, J C; Vokaer, M; Fery, P; Garbusinski, J; Van Campenhoudt, G; Blecic, S A; Bartholomé, E J

2004-12-01

Oculomotor nerve disease is a common cause of diplopia. When strabismus is present, absence of diplopia has to induce the research of either uncovering of visual fields or monocular suppression, amblyopia or blindness. We describe the case of a 41-year-old woman presenting with right oculomotor paresis and left object-centred visual neglect due to a right fronto-parietal haemorrhage expanding to the right peri-mesencephalic cisterna caused by the rupture of a right middle cerebral artery aneurysm. She never complained of diplopia despite binocular vision and progressive recovery of strabismus, excluding uncovering of visual fields. Since all other causes were excluded in this case, we hypothesise that the absence of diplopia was due to the object-centred visual neglect. Partial internal right oculomotor paresis causes an ocular deviation in abduction; the image being perceived deviated contralaterally to the left. Thus, in our case, the neglect of the left image is equivalent to a right monocular functional blindness. However, bell cancellation test clearly worsened when assessed in left monocular vision confirming that eye patching can worsen attentional visual neglect. In conclusion, our case argues for the possibility of a functional monocular blindness induced by visual neglect. We think that in presence of strabismus, absence of diplopia should induce the search for hemispatial visual neglect when supratentorial lesions are suspected.

Premotor cortex is sensitive to auditory-visual congruence for biological motion.

PubMed

Wuerger, Sophie M; Parkes, Laura; Lewis, Penelope A; Crocker-Buque, Alex; Rutschmann, Roland; Meyer, Georg F

2012-03-01

The auditory and visual perception systems have developed special processing strategies for ecologically valid motion stimuli, utilizing some of the statistical properties of the real world. A well-known example is the perception of biological motion, for example, the perception of a human walker. The aim of the current study was to identify the cortical network involved in the integration of auditory and visual biological motion signals. We first determined the cortical regions of auditory and visual coactivation (Experiment 1); a conjunction analysis based on unimodal brain activations identified four regions: middle temporal area, inferior parietal lobule, ventral premotor cortex, and cerebellum. The brain activations arising from bimodal motion stimuli (Experiment 2) were then analyzed within these regions of coactivation. Auditory footsteps were presented concurrently with either an intact visual point-light walker (biological motion) or a scrambled point-light walker; auditory and visual motion in depth (walking direction) could either be congruent or incongruent. Our main finding is that motion incongruency (across modalities) increases the activity in the ventral premotor cortex, but only if the visual point-light walker is intact. Our results extend our current knowledge by providing new evidence consistent with the idea that the premotor area assimilates information across the auditory and visual modalities by comparing the incoming sensory input with an internal representation.

GODIVA2: interactive visualization of environmental data on the Web.

PubMed

Blower, J D; Haines, K; Santokhee, A; Liu, C L

2009-03-13

GODIVA2 is a dynamic website that provides visual access to several terabytes of physically distributed, four-dimensional environmental data. It allows users to explore large datasets interactively without the need to install new software or download and understand complex data. Through the use of open international standards, GODIVA2 maintains a high level of interoperability with third-party systems, allowing diverse datasets to be mutually compared. Scientists can use the system to search for features in large datasets and to diagnose the output from numerical simulations and data processing algorithms. Data providers around Europe have adopted GODIVA2 as an INSPIRE-compliant dynamic quick-view system for providing visual access to their data.

Vision in Flies: Measuring the Attention Span

PubMed Central

Koenig, Sebastian; Wolf, Reinhard; Heisenberg, Martin

2016-01-01

A visual stimulus at a particular location of the visual field may elicit a behavior while at the same time equally salient stimuli in other parts do not. This property of visual systems is known as selective visual attention (SVA). The animal is said to have a focus of attention (FoA) which it has shifted to a particular location. Visual attention normally involves an attention span at the location to which the FoA has been shifted. Here the attention span is measured in Drosophila. The fly is tethered and hence has its eyes fixed in space. It can shift its FoA internally. This shift is revealed using two simultaneous test stimuli with characteristic responses at their particular locations. In tethered flight a wild type fly keeps its FoA at a certain location for up to 4s. Flies with a mutation in the radish gene, that has been suggested to be involved in attention-like mechanisms, display a reduced attention span of only 1s. PMID:26848852

Vision in Flies: Measuring the Attention Span.

PubMed

Koenig, Sebastian; Wolf, Reinhard; Heisenberg, Martin

2016-01-01

A visual stimulus at a particular location of the visual field may elicit a behavior while at the same time equally salient stimuli in other parts do not. This property of visual systems is known as selective visual attention (SVA). The animal is said to have a focus of attention (FoA) which it has shifted to a particular location. Visual attention normally involves an attention span at the location to which the FoA has been shifted. Here the attention span is measured in Drosophila. The fly is tethered and hence has its eyes fixed in space. It can shift its FoA internally. This shift is revealed using two simultaneous test stimuli with characteristic responses at their particular locations. In tethered flight a wild type fly keeps its FoA at a certain location for up to 4s. Flies with a mutation in the radish gene, that has been suggested to be involved in attention-like mechanisms, display a reduced attention span of only 1s.

Sensitivity and specificity of the Akena Visual Depression Inventory (AViDI-18) in Kampala (Uganda) and Cape Town (South Africa).

PubMed

Akena, Dickens; Joska, John; Stein, Dan J

2018-05-01

Visual scales may be particularly useful in screening for depression in patients with low literacy. However, few have been validated and none are in common use.AimModification and validation of a visual scale to screen for depression in low literacy settings. We assessed the validity, reliability and factor loading of a 28-item visual depression inventory using pictorial items depicting depression signs and symptoms. We validated a revised scale comprised of 18 items known as the Akena Visual Depression Inventory (AViDI-18) against a structured diagnostic interview (Mini-International Neuropsychiatric Inventory) in 343 patients in Kampala (Uganda) and Cape Town (South Africa). The 18 pictorial items had acceptable validity and reliability. The area under the curve (AUC) score of the AViDI-18 was 0.9. AUC scores were not significantly associated with sociodemographic variables. The AViDI-18 is a valid screen for depression in patients with low literacy.Declaration of interestNone.

Adult Visual Cortical Plasticity

PubMed Central

Gilbert, Charles D.; Li, Wu

2012-01-01

The visual cortex has the capacity for experience dependent change, or cortical plasticity, that is retained throughout life. Plasticity is invoked for encoding information during perceptual learning, by internally representing the regularities of the visual environment, which is useful for facilitating intermediate level vision - contour integration and surface segmentation. The same mechanisms have adaptive value for functional recovery after CNS damage, such as that associated with stroke or neurodegenerative disease. A common feature to plasticity in primary visual cortex (V1) is an association field that links contour elements across the visual field. The circuitry underlying the association field includes a plexus of long range horizontal connections formed by cortical pyramidal cells. These connections undergo rapid and exuberant sprouting and pruning in response to removal of sensory input, which can account for the topographic reorganization following retinal lesions. Similar alterations in cortical circuitry may be involved in perceptual learning, and the changes observed in V1 may be representative of how learned information is encoded throughout the cerebral cortex. PMID:22841310

Auditory Confrontation Naming in Alzheimer’s Disease

PubMed Central

Brandt, Jason; Bakker, Arnold; Maroof, David Aaron

2010-01-01

Naming is a fundamental aspect of language and is virtually always assessed with visual confrontation tests. Tests of the ability to name objects by their characteristic sounds would be particularly useful in the assessment of visually impaired patients, and may be particularly sensitive in Alzheimer’s disease (AD). We developed an Auditory Naming Task, requiring the identification of the source of environmental sounds (i.e., animal calls, musical instruments, vehicles) and multiple-choice recognition of those not identified. In two separate studies, mild-to-moderate AD patients performed more poorly than cognitively normal elderly on the Auditory Naming Task. This task was also more difficult than two versions of a comparable Visual Naming Task, and correlated more highly with Mini-Mental State Exam score. Internal consistency reliability was acceptable, although ROC analysis revealed auditory naming to be slightly less successful than visual confrontation naming in discriminating AD patients from normal subjects. Nonetheless, our Auditory Naming Test may prove useful in research and clinical practice, especially with visually-impaired patients. PMID:20981630

Four-dimensional in vivo X-ray microscopy with projection-guided gating

NASA Astrophysics Data System (ADS)

Mokso, Rajmund; Schwyn, Daniel A.; Walker, Simon M.; Doube, Michael; Wicklein, Martina; Müller, Tonya; Stampanoni, Marco; Taylor, Graham K.; Krapp, Holger G.

2015-03-01

Visualizing fast micrometer scale internal movements of small animals is a key challenge for functional anatomy, physiology and biomechanics. We combine phase contrast tomographic microscopy (down to 3.3 μm voxel size) with retrospective, projection-based gating (in the order of hundreds of microseconds) to improve the spatiotemporal resolution by an order of magnitude over previous studies. We demonstrate our method by visualizing 20 three-dimensional snapshots through the 150 Hz oscillations of the blowfly flight motor.

Static and Dynamic Flow Visualization Studies of Two Double-Delta Wing Models at High Angles of Attack

DTIC Science & Technology

1992-03-01

body, ft U.= free-stream velocity, ft/sec In the case of a wing pitching about its mid-chord location, it can be interpreted as the ratio of the...Over Moderately Swept Delta Wings," HTP -5 Workshop On Vortical Flow Breakdown and Structural Interactions, NASA Langley Research Center, August 15-16...January 6- 9,1992/Reno,Nevada. 18. User’s Manual , Flow Visualization Water Tunnel Operation for Model 1520, Eidelic International, Inc., Torrance

Visual landmark-directed scatter-hoarding of Siberian chipmunks Tamias sibiricus.

PubMed

Zhang, Dongyuan; Li, Jia; Wang, Zhenyu; Yi, Xianfeng

2016-05-01

Spatial memory of cached food items plays an important role in cache recovery by scatter-hoarding animals. However, whether scatter-hoarding animals intentionally select cache sites with respect to visual landmarks in the environment and then rely on them to recover their cached seeds for later use has not been extensively explored. Furthermore, there is a lack of evidence on whether there are sex differences in visual landmark-based food-hoarding behaviors in small rodents even though male and female animals exhibit different spatial abilities. In the present study, we used a scatter-hoarding animal, the Siberian chipmunk, Tamias sibiricus to explore these questions in semi-natural enclosures. Our results showed that T. sibiricus preferred to establish caches in the shallow pits labeled with visual landmarks (branches of Pinus sylvestris, leaves of Athyrium brevifrons and PVC tubes). In addition, visual landmarks of P. sylvestris facilitated cache recovery by T. sibiricus. We also found significant sex differences in visual landmark-based food-hoarding strategies in Siberian chipmunks. Males, rather than females, chipmunks tended to establish their caches with respect to the visual landmarks. Our studies show that T. sibiricus rely on visual landmarks to establish and recover their caches, and that sex differences exist in visual landmark-based food hoarding in Siberian chipmunks. © 2015 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

Space Shuttle Familiarization

NASA Technical Reports Server (NTRS)

Mellett, Kevin

2006-01-01

This slide presentation visualizes the NASA space center and research facility sites, as well as the geography, launching sites, launching pads, rocket launching, pre-flight activities, and space shuttle ground operations located at NASA Kennedy Space Center. Additionally, highlights the international involvement behind the International Space Station and the space station mobile servicing system. Extraterrestrial landings, surface habitats and habitation systems, outposts, extravehicular activity, and spacecraft rendezvous with the Earth return vehicle are also covered.

The Value of Data and Metadata Standardization for Interoperability in Giovanni Or: Why Your Product's Metadata Causes Us Headaches!

NASA Technical Reports Server (NTRS)

Smit, Christine; Hegde, Mahabaleshwara; Strub, Richard; Bryant, Keith; Li, Angela; Petrenko, Maksym

2017-01-01

Giovanni is a data exploration and visualization tool at the NASA Goddard Earth Sciences Data Information Services Center (GES DISC). It has been around in one form or another for more than 15 years. Giovanni calculates simple statistics and produces 22 different visualizations for more than 1600 geophysical parameters from more than 90 satellite and model products. Giovanni relies on external data format standards to ensure interoperability, including the NetCDF CF Metadata Conventions. Unfortunately, these standards were insufficient to make Giovanni's internal data representation truly simple to use. Finding and working with dimensions can be convoluted with the CF Conventions. Furthermore, the CF Conventions are silent on machine-friendly descriptive metadata such as the parameter's source product and product version. In order to simplify analyzing disparate earth science data parameters in a unified way, we developed Giovanni's internal standard. First, the format standardizes parameter dimensions and variables so they can be easily found. Second, the format adds all the machine-friendly metadata Giovanni needs to present our parameters to users in a consistent and clear manner. At a glance, users can grasp all the pertinent information about parameters both during parameter selection and after visualization.

Visualization of International Solar-Terrestrial Physics Program (ISTP) data

NASA Technical Reports Server (NTRS)

Kessel, Ramona L.; Candey, Robert M.; Hsieh, Syau-Yun W.; Kayser, Susan

1995-01-01

The International Solar-Terrestrial Physics Program (ISTP) is a multispacecraft, multinational program whose objective is to promote further understanding of the Earth's complex plasma environment. Extensive data sharing and data analysis will be needed to ensure the success of the overall ISTP program. For this reason, there has been a special emphasis on data standards throughout ISTP. One of the key tools will be the common data format (CDF), developed, maintained, and evolved at the National Space Science Data Center (NSSDC), with the set of ISTP implementation guidelines specially designed for space physics data sets by the Space Physics Data Facility (associated with the NSSDC). The ISTP guidelines were developed to facilitate searching, plotting, merging, and subsetting of data sets. We focus here on the plotting application. A prototype software package was developed to plot key parameter (KP) data from the ISTP program at the Science Planning and Operations Facility (SPOF). The ISTP Key Parameter Visualization Tool is based on the Interactive Data Language (IDL) and is keyed to the ISTP guidelines, reading data stored in CDF. With the combination of CDF, the ISTP guidelines, and the visualization software, we can look forward to easier and more effective data sharing and use among ISTP scientists.

The Portable War Room Research Project

NASA Technical Reports Server (NTRS)

Govers, Francis X., III; Fry, Mark

1997-01-01

The Portable War Room is an internal TASC project to research and develop a visualization and simulation environment to provide for decision makers the power to review the past, understand the present, and peer into the future.

Automatic internal crack detection from a sequence of infrared images with a triple-threshold Canny edge detector

NASA Astrophysics Data System (ADS)

Wang, Gaochao; Tse, Peter W.; Yuan, Maodan

2018-02-01

Visual inspection and assessment of the condition of metal structures are essential for safety. Pulse thermography produces visible infrared images, which have been widely applied to detect and characterize defects in structures and materials. When active thermography, a non-destructive testing tool, is applied, the necessity of considerable manual checking can be avoided. However, detecting an internal crack with active thermography remains difficult, since it is usually invisible in the collected sequence of infrared images, which makes the automatic detection of internal cracks even harder. In addition, the detection of an internal crack can be hindered by a complicated inspection environment. With the purpose of putting forward a robust and automatic visual inspection method, a computer vision-based thresholding method is proposed. In this paper, the image signals are a sequence of infrared images collected from the experimental setup with a thermal camera and two flash lamps as stimulus. The contrast of pixels in each frame is enhanced by the Canny operator and then reconstructed by a triple-threshold system. Two features, mean value in the time domain and maximal amplitude in the frequency domain, are extracted from the reconstructed signal to help distinguish the crack pixels from others. Finally, a binary image indicating the location of the internal crack is generated by a K-means clustering method. The proposed procedure has been applied to an iron pipe, which contains two internal cracks and surface abrasion. Some improvements have been made for the computer vision-based automatic crack detection methods. In the future, the proposed method can be applied to realize the automatic detection of internal cracks from many infrared images for the industry.

Orienting attention to visual or verbal/auditory imagery differentially impairs the processing of visual stimuli.

PubMed

Villena-González, Mario; López, Vladimir; Rodríguez, Eugenio

2016-05-15

When attention is oriented toward inner thoughts, as spontaneously occurs during mind wandering, the processing of external information is attenuated. However, the potential effects of thought's content regarding sensory attenuation are still unknown. The present study aims to assess if the representational format of thoughts, such as visual imagery or inner speech, might differentially affect the sensory processing of external stimuli. We recorded the brain activity of 20 participants (12 women) while they were exposed to a probe visual stimulus in three different conditions: executing a task on the visual probe (externally oriented attention), and two conditions involving inward-turned attention i.e. generating inner speech and performing visual imagery. Event-related potentials results showed that the P1 amplitude, related with sensory response, was significantly attenuated during both task involving inward attention compared with external task. When both representational formats were compared, the visual imagery condition showed stronger attenuation in sensory processing than inner speech condition. Alpha power in visual areas was measured as an index of cortical inhibition. Larger alpha amplitude was found when participants engaged in an internal thought contrasted with the external task, with visual imagery showing even more alpha power than inner speech condition. Our results show, for the first time to our knowledge, that visual attentional processing to external stimuli during self-generated thoughts is differentially affected by the representational format of the ongoing train of thoughts. Copyright © 2016 Elsevier Inc. All rights reserved.

Visualization of the internal globus pallidus: sequence and orientation for deep brain stimulation using a standard installation protocol at 3.0 Tesla.

PubMed

Nölte, Ingo S; Gerigk, Lars; Al-Zghloul, Mansour; Groden, Christoph; Kerl, Hans U

2012-03-01

Deep-brain stimulation (DBS) of the internal globus pallidus (GPi) has shown remarkable therapeutic benefits for treatment-resistant neurological disorders including dystonia and Parkinson's disease (PD). The success of the DBS is critically dependent on the reliable visualization of the GPi. The aim of the study was to evaluate promising 3.0 Tesla magnetic resonance imaging (MRI) methods for pre-stereotactic visualization of the GPi using a standard installation protocol. MRI at 3.0 T of nine healthy individuals and of one patient with PD was acquired (FLAIR, T1-MPRAGE, T2-SPACE, T2*-FLASH2D, susceptibility-weighted imaging mapping (SWI)). Image quality and visualization of the GPi for each sequence were assessed by two neuroradiologists independently using a 6-point scale. Axial, coronal, and sagittal planes of the T2*-FLASH2D images were compared. Inter-rater reliability, contrast-to-noise ratios (CNR) and signal-to-noise ratios (SNR) for the GPi were determined. For illustration, axial T2*-FLASH2D images were fused with a section schema of the Schaltenbrand-Wahren stereotactic atlas. The GPi was best and reliably visualized in axial and to a lesser degree on coronal T2*-FLASH2D images. No major artifacts in the GPi were observed in any of the sequences. SWI offered a significantly higher CNR for the GPi compared to standard T2-weighted imaging using the standard parameters. The fusion of the axial T2*-FLASH2D images and the atlas projected the GPi clearly in the boundaries of the section schema. Using a standard installation protocol at 3.0 T T2*-FLASH2D imaging (particularly axial view) provides optimal and reliable delineation of the GPi.

Psychometric analyses to improve the Dutch ICF Activity Inventory.

PubMed

Bruijning, Janna E; van Rens, Ger; Knol, Dirk; van Nispen, Ruth

2013-08-01

In the past, rehabilitation centers for the visually impaired used unstructured or semistructured methods to assess rehabilitation needs of their patients. Recently, an extensive instrument, the Dutch ICF Activity Inventory (D-AI), was developed to systematically investigate rehabilitation needs of visually impaired adults and to evaluate rehabilitation outcomes. The purpose of this study was to investigate the underlying factor structure and other psychometric properties to shorten and improve the D-AI. The D-AI was administered to 241 visually impaired persons who recently enrolled in a multidisciplinary rehabilitation center. The D-AI uses graded scores to assess the importance and difficulty of 65 rehabilitation goals. For high-priority goals (e.g., daily meal preparation), the difficulty of underlying tasks (e.g., read recipes, cut vegetables) was assessed. To reduce underlying task items (>950), descriptive statistics were investigated and factor analyses were performed for several goals. The internal consistency reliability and test-retest reliability of the D-AI were investigated by calculating Cronbach α and Cohen (weighted) κ. Finally, consensus-based discussions were used to shorten and improve the D-AI. Except for one goal, factor analysis model parameters were at least reasonable. Internal consistency reliability was satisfactory (range, 0.74 to 0.93). In total, 60% of the 65 goal importance items and 84.4% of the goal difficulty items showed moderate to almost perfect κ values (≥0.40). After consensus-based discussions, a new D-AI was produced, containing 48 goals and less than 500 tasks. The analyses were an important step in the validation process of the D-AI and to develop a more feasible assessment tool to investigate rehabilitation needs of visually impaired persons in a systematic way. The D-AI is currently implemented in all Dutch rehabilitation centers serving all visually impaired adults with various rehabilitation needs.

Visualization of Data Regarding Infections Using Eye Tracking Techniques.

PubMed

Yoon, Sunmoo; Cohen, Bevin; Cato, Kenrick D; Liu, Jianfang; Larson, Elaine L

2016-05-01

To evaluate ease of use and usefulness for nurses of visualizations of infectious disease transmission in a hospital. An observational study was used to evaluate perceptions of several visualizations of data extracted from electronic health records designed using a participatory approach. Twelve nurses in the master's program in an urban research-intensive nursing school participated in May 2015. A convergent parallel mixed method was used to evaluate nurses' perceptions on ease of use and usefulness of five visualization conveying trends in hospital infection transmission applying think-aloud, interview, and eye-tracking techniques. Subjective data from the interview and think-aloud techniques indicated that participants preferred the traditional line graphs in simple data representation due to their familiarity, clarity, and easiness to read. An objective quantitative measure of eye movement analysis (444,421 gaze events) identified a high degree of participants' attention span in infographics in all three scenarios. All participants responded with the correct answer within 1 min in comprehensive tests. A user-centric approach was effective in developing and evaluating visualizations for hospital infection transmission. For the visualizations designed by the users, the participants were easily able to comprehend the infection visualizations on both line graphs and infographics for simple visualization. The findings from the objective comprehension test and eye movement and subjective attitudes support the feasibility of integrating user-centric visualization designs into electronic health records, which may inspire clinicians to be mindful of hospital infection transmission. Future studies are needed to investigate visualizations and motivation, and the effectiveness of visualization on infection rate. This study designed visualization images using clinical data from electronic health records applying a user-centric approach. The design insights can be applied for visualizing patient data in electronic health records. © 2016 Sigma Theta Tau International.

Visions of our Planet's Atmosphere, Land and Oceans: NASA/NOAA Electronic-Theater 2002. Spectacular Visualizations of our Blue Marble

NASA Technical Reports Server (NTRS)

Hasler, A. F.; Starr, David (Technical Monitor)

2002-01-01

Spectacular Visualizations of our Blue Marble The NASA/NOAA Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to the 2002 Winter Olympic Stadium Site of the Olympic Opening and Closing Ceremonies in Salt Lake City. Fly in and through Olympic Alpine Venues using 1 m IKONOS "Spy Satellite" data. Go back to the early weather satellite images from the 1960s and see them contrasted with the latest US and international global satellite weather movies including hurricanes & "tornadoes". See the latest visualizations of spectacular images from NASA/NOAA remote sensing missions like Terra, GOES, TRMM, SeaWiFS, Landsat 7 including new 1 - min GOES rapid scan image sequences of Nov 9th 2001 Midwest tornadic thunderstorms and have them explained. See how High-Definition Television (HDTV) is revolutionizing the way we communicate science. (In cooperation with the American Museum of Natural History in NYC). See dust storms in Africa and smoke plumes from fires in Mexico. See visualizations featured on the covers of Newsweek, TIME, National Geographic, Popular Science & on National & International Network TV. New computer software tools allow us to roam & zoom through massive global images e.g. Landsat tours of the US, and Africa, showing desert and mountain geology as well as seasonal changes in vegetation. See animations of the polar ice packs and the motion of gigantic Antarctic Icebergs from SeaWinds data. Spectacular new visualizations of the global atmosphere & oceans are shown. See vertexes and currents in the global oceans that bring up the nutrients to feed tiny algae and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nicola Nina climate changes. See the city lights, fishing fleets, gas flares and biomass burning of the Earth at night observed by the "night-vision" DMSP military satellite.

The impact of using visual images of the body within a personalized health risk assessment: an experimental study.

PubMed

Hollands, Gareth J; Marteau, Theresa M

2013-05-01

To examine the motivational impact of the addition of a visual image to a personalized health risk assessment and the underlying cognitive and emotional mechanisms. An online experimental study in which participants (n = 901; mean age = 27.2 years; 61.5% female) received an assessment and information focusing on the health implications of internal body fat and highlighting the protective benefits of physical activity. Participants were randomized to receive this in either (a) solely text form (control arm) or (b) text plus a visual image of predicted internal body fat (image arm). Participants received information representing one of three levels of health threat, determined by how physically active they were: high, moderate or benign. Main outcome measures were physical activity intentions (assessed pre- and post-intervention), worry, coherence and believability of the information. Intentions to undertake recommended levels of physical activity were significantly higher in the image arm, but only amongst those participants who received a high-threat communication. Believability of the results received was greater in the image arm and mediated the intervention effect on intentions. The addition of a visual image to a risk assessment led to small but significant increases in intentions to undertake recommended levels of physical activity in those at increased health risk. Limitations of the study and implications for future research are discussed. What is already known on this subject? Health risk information that is personalized to the individual may more strongly motivate risk-reducing behaviour change. Little prior research attention has been paid specifically to the motivational impact of personalized visual images and underlying mechanisms. What does this study add? In an experimental design, it is shown that receipt of visual images increases intentions to engage in risk-reducing behaviour, although only when a significant level of threat is presented. The study suggests that images increase the believability of health risk information and this may underlie motivational impact. © 2012 The British Psychological Society.

Associations of physical activity with driving-related cognitive abilities in older drivers: an exploratory study.

PubMed

Marmeleira, José; Ferreira, Inês; Melo, Filipe; Godinho, Mário

2012-10-01

The purpose of this study was to examine the associations between hysical activity and driving-related cognitive abilities of older drivers. Thirty-eight female and male drivers ages 61 to 81 years (M = 70.2, SD = 5.0) responded to the International Physical Activity Questionnaire and were assessed on a battery of neuropsychological tests, which included measures of visual attention, executive functioning, mental status, visuospatial ability, and memory. A higher amount of reported physical activity was significantly correlated with better scores on tests of visual processing speed and divided visual attention. Higher amounts of physical activity was significantly associated with a better composite score for visual attention, but its correlation with the composite score for executive functioning was not significant. These findings support the hypothesis that pzhysical activity is associated with preservation of specific driving-related cognitive abilities of older adults.

Simulation environment and graphical visualization environment: a COPD use-case.

PubMed

Huertas-Migueláñez, Mercedes; Mora, Daniel; Cano, Isaac; Maier, Dieter; Gomez-Cabrero, David; Lluch-Ariet, Magí; Miralles, Felip

2014-11-28

Today, many different tools are developed to execute and visualize physiological models that represent the human physiology. Most of these tools run models written in very specific programming languages which in turn simplify the communication among models. Nevertheless, not all of these tools are able to run models written in different programming languages. In addition, interoperability between such models remains an unresolved issue. In this paper we present a simulation environment that allows, first, the execution of models developed in different programming languages and second the communication of parameters to interconnect these models. This simulation environment, developed within the Synergy-COPD project, aims at helping and supporting bio-researchers and medical students understand the internal mechanisms of the human body through the use of physiological models. This tool is composed of a graphical visualization environment, which is a web interface through which the user can interact with the models, and a simulation workflow management system composed of a control module and a data warehouse manager. The control module monitors the correct functioning of the whole system. The data warehouse manager is responsible for managing the stored information and supporting its flow among the different modules. It has been proved that the simulation environment presented here allows the user to research and study the internal mechanisms of the human physiology by the use of models via a graphical visualization environment. A new tool for bio-researchers is ready for deployment in various use cases scenarios.

Applying microCT and 3D visualization to Jurassic silicified conifer seed cones: A virtual advantage over thin-sectioning1

PubMed Central

Gee, Carole T.

2013-01-01

• Premise of the study: As an alternative to conventional thin-sectioning, which destroys fossil material, high-resolution X-ray computed tomography (also called microtomography or microCT) integrated with scientific visualization, three-dimensional (3D) image segmentation, size analysis, and computer animation is explored as a nondestructive method of imaging the internal anatomy of 150-million-year-old conifer seed cones from the Late Jurassic Morrison Formation, USA, and of recent and other fossil cones. • Methods: MicroCT was carried out on cones using a General Electric phoenix v|tome|x s 240D, and resulting projections were processed with visualization software to produce image stacks of serial single sections for two-dimensional (2D) visualization, 3D segmented reconstructions with targeted structures in color, and computer animations. • Results: If preserved in differing densities, microCT produced images of internal fossil tissues that showed important characters such as seed phyllotaxy or number of seeds per cone scale. Color segmentation of deeply embedded seeds highlighted the arrangement of seeds in spirals. MicroCT of recent cones was even more effective. • Conclusions: This is the first paper on microCT integrated with 3D segmentation and computer animation applied to silicified seed cones, which resulted in excellent 2D serial sections and segmented 3D reconstructions, revealing features requisite to cone identification and understanding of strobilus construction. PMID:25202495

Stereoscopic augmented reality using ultrasound volume rendering for laparoscopic surgery in children

NASA Astrophysics Data System (ADS)

Oh, Jihun; Kang, Xin; Wilson, Emmanuel; Peters, Craig A.; Kane, Timothy D.; Shekhar, Raj

2014-03-01

In laparoscopic surgery, live video provides visualization of the exposed organ surfaces in the surgical field, but is unable to show internal structures beneath those surfaces. The laparoscopic ultrasound is often used to visualize the internal structures, but its use is limited to intermittent confirmation because of the need for an extra hand to maneuver the ultrasound probe. Other limitations of using ultrasound are the difficulty of interpretation and the need for an extra port. The size of the ultrasound transducer may also be too large for its usage in small children. In this paper, we report on an augmented reality (AR) visualization system that features continuous hands-free volumetric ultrasound scanning of the surgical anatomy and video imaging from a stereoscopic laparoscope. The acquisition of volumetric ultrasound image is realized by precisely controlling a back-and-forth movement of an ultrasound transducer mounted on a linear slider. Furthermore, the ultrasound volume is refreshed several times per minute. This scanner will sit outside of the body in the envisioned use scenario and could be even integrated into the operating table. An overlay of the maximum intensity projection (MIP) of ultrasound volume on the laparoscopic stereo video through geometric transformations features an AR visualization system particularly suitable for children, because ultrasound is radiation-free and provides higher-quality images in small patients. The proposed AR representation promises to be better than the AR representation using ultrasound slice data.

Usefulness of real-time three-dimensional ultrasonography in percutaneous nephrostomy: an animal study.

PubMed

Hongzhang, Hong; Xiaojuan, Qin; Shengwei, Zhang; Feixiang, Xiang; Yujie, Xu; Haibing, Xiao; Gallina, Kazobinka; Wen, Ju; Fuqing, Zeng; Xiaoping, Zhang; Mingyue, Ding; Huageng, Liang; Xuming, Zhang

2018-05-17

To evaluate the effect of real-time three-dimensional (3D) ultrasonography (US) in guiding percutaneous nephrostomy (PCN). A hydronephrosis model was devised in which the ureters of 16 beagles were obstructed. The beagles were divided equally into groups 1 and 2. In group 1, the PCN was performed using real-time 3D US guidance, while in group 2 the PCN was guided using two-dimensional (2D) US. Visualization of the needle tract, length of puncture time and number of puncture times were recorded for the two groups. In group 1, score for visualization of the needle tract, length of puncture time and number of puncture times were 3, 7.3 ± 3.1 s and one time, respectively. In group 2, the respective results were 1.4 ± 0.5, 21.4 ± 5.8 s and 2.1 ± 0.6 times. The visualization of needle tract in group 1 was superior to that in group 2, and length of puncture time and number of puncture times were both lower in group 1 than in group 2. Real-time 3D US-guided PCN is superior to 2D US-guided PCN in terms of visualization of needle tract and the targeted pelvicalyceal system, leading to quick puncture. Real-time 3D US-guided puncture of the kidney holds great promise for clinical implementation in PCN. © 2018 The Authors BJU International © 2018 BJU International Published by John Wiley & Sons Ltd.

Alcohol marketing in televised international football: frequency analysis

PubMed Central

2014-01-01

Background Alcohol marketing includes sponsorship of individuals, organisations and sporting events. Football (soccer) is one of the most popular spectator sports worldwide. No previous studies have quantified the frequency of alcohol marketing in a high profile international football tournament. The aims were to determine: the frequency and nature of visual references to alcohol in a representative sample of EURO2012 matches broadcast in the UK; and if frequency or nature varied between matches broadcast on public service and commercial channels, or between matches that did and did not feature England. Methods Eight matches selected by stratified random sampling were recorded. All visual references to alcohol were identified using a tool with high inter-rater reliability. Results 1846 visual references to alcohol were identified over 1487 minutes of broadcast - an average of 1.24 references per minute. The mean number of references per minute was higher in matches that did vs did not feature England (p = 0.004), but did not differ between matches broadcast on public service vs commercial channels (p = 0.92). Conclusions The frequency of visual references to alcohol was universally high and higher in matches featuring the only UK home team - England - suggesting that there may be targeting of particularly highly viewed matches. References were embedded in broadcasts, and not particular to commercial channels including paid-for advertising. New UK codes-of-conduct on alcohol marketing at sporting events will not reduce the level of marketing reported here. PMID:24885718

LASIK for myopia and astigmatism using the SCHWIND AMARIS excimer laser: an international multicenter trial.

PubMed

Arbelaez, Maria Clara; Aslanides, Ioannis M; Barraquer, Carmen; Carones, Francesco; Feuermannova, Alena; Neuhann, Tobias; Rozsival, Pavel

2010-02-01

To assess the efficacy, predictability, and safety of LASIK for the surgical correction of low to moderate myopia with astigmatism using the SCHWIND AMARIS excimer laser. Six international study sites enrolled 358 eyes with a manifest refraction spherical equivalent (MRSE) from -0.50 to -7.38 diopters (D) (mean sphere: -3.13+/-1.58 D) with up to -5.00 D of astigmatism (mean: -0.69+/-0.67 D). All eyes underwent treatment with the nonwavefront-guided aspheric algorithm of the SCHWIND AMARIS excimer laser. All eyes were targeted for emmetropia. Refractive outcomes and corneal higher order aberrations were analyzed pre- and postoperatively. Visual quality was assessed using photopic and mesopic contrast sensitivity. Six-month postoperative outcomes are reported. At 6 months postoperative, the MRSE for all eyes was -0.21+/-0.20 D, and 96% (343/358) of eyes had MRSE within +/-0.50 D. Uncorrected visual acuity was 20/20 or better in 98% (351/358) of eyes, and no eyes lost 2 or more lines of best spectacle-corrected visual acuity. The total corneal higher order aberrations root-mean-square increased by 0.09 microm, spherical aberration increased by 0.08 microm, and coma increased by 0.04 microm postoperatively. Photopic and mesopic contrast sensitivity did not change 6 months postoperatively. Treatment of myopia with astigmatism using the SCHWIND AMARIS excimer laser is safe, efficacious, predictable, and maintains visual quality.

Perception of affordances during long-term exposure to weightlessness in the International Space station.

PubMed

Bourrelly, Aurore; McIntyre, Joseph; Luyat, Marion

2015-09-01

On Earth, visual eye height (VEH)--the distance from the observer's line of gaze to the ground in the visual scene--constitutes an effective cue in perceiving affordance such as the passability through apertures, based on the assumption that one's feet are on the ground. In the present study, we questioned whether an observer continues to use VEH to estimate the width of apertures during long-term exposure to weightlessness, where contact with the floor is not required. Ten astronauts were tested in preflight, inflight in the International Space Station, and postflight sessions. They were asked to adjust the opening of a virtual doorway displayed on a laptop device until it was perceived to be just wide enough to pass through (i.e., the critical aperture). We manipulated VEH by raising and lowering the level of the floor in the visual scene. We observed an effect of VEH manipulation on the critical aperture. When VEH decreased, the critical aperture decreased too, suggesting that widths relative to the body were perceived to be larger when VEH was smaller. There was no overall significant session effect, but the analysis of between-subjects variability revealed two participant profile groups. The effect of weightlessness was different for these two groups even though the VEH strategy remained operational during spaceflight. This study shows that the VEH strategy appears to be very robust and can be used, if necessary, in inappropriate circumstances such as free-floating, perhaps promoted by the nature of the visual scene.

Leg venography (image)

MedlinePlus

... procedure where contrast material is injected through a catheter in a vein to help visualize the internal structures by using x-rays. The test is used to identify and locate thrombi (blood clots) in the veins of the extremity that is ...

NEW PROGRAMMING ENVIRONMENTS FOR UNCERTAINTY ANALYSIS

EPA Science Inventory

We live in a world of faster computers, better GUI's and visualization technology, increasing international cooperation made possible by new digital infrastructure, new agreements between US federal agencies (such as ISCMEM), new European Union programs (such as Harmoniqua), and ...

Memory for Details with Self-Referencing

PubMed Central

Serbun, Sarah J.; Shih, Joanne Y.; Gutchess, Angela H.

2011-01-01

Self-referencing benefits item memory, but little is known about the ways in which referencing the self affects memory for details. Experiment 1 assessed whether the effects of self-referencing operate only at the item, or general, level or also enhance memory for specific visual details of objects. Participants incidentally encoded objects by making judgments in reference to the self, a close other (one’s mother), or a familiar other (Bill Clinton). Results indicate that referencing the self or a close other enhances both specific and general memory. Experiments 2 and 3 assessed verbal memory for source in a task that relied on distinguishing between different mental operations (internal sources). Results indicate that self-referencing disproportionately enhances source memory, relative to conditions referencing other people, semantic, or perceptual information. We conclude that self-referencing not only enhances specific memory for both visual and verbal information, but can disproportionately improve memory for specific internal source details as well. PMID:22092106

A Brazilian-Portuguese version of the Kinesthetic and Visual Motor Imagery Questionnaire.

PubMed

Demanboro, Alan; Sterr, Annette; Anjos, Sarah Monteiro Dos; Conforto, Adriana Bastos

2018-01-01

Motor imagery has emerged as a potential rehabilitation tool in stroke. The goals of this study were: 1) to develop a translated and culturally-adapted Brazilian-Portugese version of the Kinesthetic and Visual Motor Imagery Questionnaire (KVIQ20-P); 2) to evaluate the psychometric characteristics of the scale in a group of patients with stroke and in an age-matched control group; 3) to compare the KVIQ20 performance between the two groups. Test-retest, inter-rater reliabilities, and internal consistencies were evaluated in 40 patients with stroke and 31 healthy participants. In the stroke group, ICC confidence intervals showed excellent test-retest and inter-rater reliabilities. Cronbach's alpha also indicated excellent internal consistency. Results for controls were comparable to those obtained in persons with stroke. The excellent psychometric properties of the KVIQ20-P should be considered during the design of studies of motor imagery interventions for stroke rehabilitation.

Exceptional preservation of eye structure in arthropod visual predators from the Middle Jurassic

PubMed Central

Vannier, Jean; Schoenemann, Brigitte; Gillot, Thomas; Charbonnier, Sylvain; Clarkson, Euan

2016-01-01

Vision has revolutionized the way animals explore their environment and interact with each other and rapidly became a major driving force in animal evolution. However, direct evidence of how ancient animals could perceive their environment is extremely difficult to obtain because internal eye structures are almost never fossilized. Here, we reconstruct with unprecedented resolution the three-dimensional structure of the huge compound eye of a 160-million-year-old thylacocephalan arthropod from the La Voulte exceptional fossil biota in SE France. This arthropod had about 18,000 lenses on each eye, which is a record among extinct and extant arthropods and is surpassed only by modern dragonflies. Combined information about its eyes, internal organs and gut contents obtained by X-ray microtomography lead to the conclusion that this thylacocephalan arthropod was a visual hunter probably adapted to illuminated environments, thus contradicting the hypothesis that La Voulte was a deep-water environment. PMID:26785293

Eugenics visualized: the exhibit of the Third International Congress of Eugenics, 1932.

PubMed

Stillwell, Devon

2012-01-01

This article investigates the exhibit of the Third International Congress of Eugenics, which was organized by Harry Hamilton Laughlin and showcased at the American Museum of Natural History in 1932. It argues that the exhibit's displays shaped popular eugenic ideology by connecting particular eugenic principles to specific visual representations that were experienced in relation to binaries such as the artistically traditional and the modern, the classical and the grotesque, and the scientific and the spectacle (or the "freak" and the medical specimen). These dichotomies were, in turn, experienced within the context of the exhibit's overall theme of eugenics as anchored in the past and the future and concern over the differential birthrate. The exhibit to the Third Congress provides insight into growing tensions within the eugenics movement of the 1930s, the importance of positive eugenics, the aesthetics of heredity, and how the "scientific truths" of a given era are publicized and perpetuated.

Exceptional preservation of eye structure in arthropod visual predators from the Middle Jurassic.

PubMed

Vannier, Jean; Schoenemann, Brigitte; Gillot, Thomas; Charbonnier, Sylvain; Clarkson, Euan

2016-01-19

Vision has revolutionized the way animals explore their environment and interact with each other and rapidly became a major driving force in animal evolution. However, direct evidence of how ancient animals could perceive their environment is extremely difficult to obtain because internal eye structures are almost never fossilized. Here, we reconstruct with unprecedented resolution the three-dimensional structure of the huge compound eye of a 160-million-year-old thylacocephalan arthropod from the La Voulte exceptional fossil biota in SE France. This arthropod had about 18,000 lenses on each eye, which is a record among extinct and extant arthropods and is surpassed only by modern dragonflies. Combined information about its eyes, internal organs and gut contents obtained by X-ray microtomography lead to the conclusion that this thylacocephalan arthropod was a visual hunter probably adapted to illuminated environments, thus contradicting the hypothesis that La Voulte was a deep-water environment.

Memory for details with self-referencing.

PubMed

Serbun, Sarah J; Shih, Joanne Y; Gutchess, Angela H

2011-11-01

Self-referencing benefits item memory, but little is known about the ways in which referencing the self affects memory for details. Experiment 1 assessed whether the effects of self-referencing operate only at the item, or general, level or whether they also enhance memory for specific visual details of objects. Participants incidentally encoded objects by making judgements in reference to the self, a close other (one's mother), or a familiar other (Bill Clinton). Results indicate that referencing the self or a close other enhances both specific and general memory. Experiments 2 and 3 assessed verbal memory for source in a task that relied on distinguishing between different mental operations (internal sources). The results indicate that self-referencing disproportionately enhances source memory, relative to conditions referencing other people, semantic, or perceptual information. We conclude that self-referencing not only enhances specific memory for both visual and verbal information, but can also disproportionately improve memory for specific internal source details.

Poster presentations at medical conferences: an effective way of disseminating research?

PubMed

Goodhand, J R; Giles, C L; Wahed, M; Irving, P M; Langmead, L; Rampton, D S

2011-04-01

This study aimed to ascertain the value of posters at medical meetings to presenters and delegates. The usefulness of posters to presenters at national and international meetings was evaluated by assessing the numbers of delegates visiting them and the reasons why they visited. Memorability of selected posters was assessed and factors influencing their appeal to expert delegates identified. At both the national and international meetings, very few delegates (< 5%) visited posters. Only a minority read them and fewer asked useful questions. Recall of content was so poor that it prevented identification of factors improving their memorability. Factors increasing posters' visual appeal included their scientific content, pictures/graphs and limited use of words. Few delegates visit posters and those doing so recall little of their content. To engage their audience, researchers should design visually appealing posters by presenting high quality data in pictures or graphs without an excess of words.

Proceedings of the Conference of the International Group for the Psychology of Mathematics Education (PME) (24th, Hiroshima, Japan, July 23-27, 2000), Volume 2.

ERIC Educational Resources Information Center

Nakahara, Tadao, Ed.; Koyama, Masataka, Ed.

The second volume of the 24th annual conference of the International Group for the Psychology of Mathematics Education contains full research report papers. Papers include: (1) "What you see is what you get: The influence of visualization on the perception of data structures" (Dan Aharoni); (2) "Exploring the transparency of graphs and graphing"…

Interfacial bioconjugation on emulsion droplet for biosensors.

PubMed

Zhang, Qifan; Scigliano, Anita; Biver, Tarita; Pucci, Andrea; Swager, Timothy M

2018-04-13

Interfacial bioconjugation methods are developed for intact liquid emulsion droplets. Complex emulsion droplets having internal hydrocarbon and fluorocarbon immiscible structured phases maintain a dynamic interface for controlled interfacial reactivity. The internal morphological change after binding to biomolecules is readily visualized and detected by light transmission, which provides a platform for the formation of inexpensive and portable bio-sensing assays for enzymes, antibodies, nucleic acids and carbohydrates. Copyright © 2018. Published by Elsevier Ltd.

Support for the 38th International Conference on High Energy Physics, 3-10 August 2016

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Young-Kee

The 38th International Conference on High Energy Physics (ICHEP) held in Chicago from August 3 to 10, 2016 was for physicists from around the world to gather to share the latest advancements in particle physics, astrophysics/cosmology, and accelerator science and to discuss plans for major future facilities. DOE funding provided partial support for space rental audio-visual services for scientific presentations at the conference.