Objectives:Pelvic fracture urethral injuries(PFUI)result from traumatic disruption of the urethra.A significant proportion of cases are complex rendering their management challenging.We described management strategies...Objectives:Pelvic fracture urethral injuries(PFUI)result from traumatic disruption of the urethra.A significant proportion of cases are complex rendering their management challenging.We described management strategies for eight different complex PFUI scenarios.Methods:Our centre is a tertiary referral centre for complex PFUI cases.We maintain a prospective database(1995e2016),which we retrospectively analysed.All patients with PFUI managed at our institute were included.Results:Over two decades 1062 cases of PFUI were managed at our institute(521 primary and 541 redo cases).Most redo cases were referred to us from other centres.Redo cases had up to five prior attempts at urethroplasty.We managed complex cases,which included bulbar ischemia,young boys and girls with PFUI,PFUI with double block,concomitant PFUI and iatrogenic anterior urethral strictures.Bulbar ischemia merits substitution urethroplasty,most commonly,using pedicled preputial tube.PFUI in young girls is usually associated with urethrovaginal fistula.Young boys with PFUI commonly have a long gap necessitating trans-abdominal approach.Our success rate with individualised management is 85.60%in primary cases,79.13%in redo cases and 82.40%in cases of bulbar ischemia.Conclusion:The definition of complex PFUI is ever expanding.The best chance of success is at the first attempt.Anastomotic urethroplasty for PFUI should be performed in experienced hands at high volume centres.展开更多
BACKGROUND A male urethral disruption injury is a urological emergency.Primary endoscopic realignment(PER)refers to reestablishment of urethral alignment via indwelling urethral catheter by cystoscope,which is recomme...BACKGROUND A male urethral disruption injury is a urological emergency.Primary endoscopic realignment(PER)refers to reestablishment of urethral alignment via indwelling urethral catheter by cystoscope,which is recommended as the optimal emergent treatment approach for reducing the likelihood of complications following injury.However,the prior literature suggests the success rate of PER to be relatively low due to complicated urethral disruption.We report a modified PER approach that serves to improve both the success rate and safety of the treatment.CASE SUMMARY A 19-year-old male patient presented with multiple pelvic fractures and complete urethral disruption following a high-velocity traffic accident.The patient’s abdominal computed tomography and retrograde urethrography results revealed complete urethral disruption at the bulbar urethra,with hematoma and contrast medium extravasation that extended into the extraperitoneal space.The conventional retrograde PER by cystoscope failed due to severe disruption and considerable hematoma.Modified simultaneous antegrade and retrograde PER was performed by means of semi-rigid ureteroscopy via a suprapubic Foley catheter and cystoscopy via the external urethra.An antegrade guidewire was passed through the bladder neck and then pulled out through the external urethral meatus with a cystoscope.Urethral continuity was achieved after a 16-Fr silicone Foley catheter was indwelled into the bladder along the guidewire.The patient recovered well,achieving voiding continence and avoiding further operation for urethral stricture.CONCLUSION Modified PER via suprapubic Foley catheter represents a promising and safe treatment approach in patients with posterior urethral injuries.展开更多
Posterior urethral injuries typically arise in the context of a pelvic fracture.Retrograde urethrography is the preferred diagnostic test in trauma patients with pelvic fracture where a posterior urethral rupture is s...Posterior urethral injuries typically arise in the context of a pelvic fracture.Retrograde urethrography is the preferred diagnostic test in trauma patients with pelvic fracture where a posterior urethral rupture is suspected.Pelvic fractures however preclude the adequate positioning of the patient on the X-ray table on admission and computed tomography scan with intravenous contrast and delayed films generally performed first.Suprapubic bladder catheter placement under ultrasound guidance should be performed whenever a posterior urethral disruption is suspected.Early diagnosis and proper acute management decrease the associated complications,such as strictures,urinary incontinence and erectile dysfunction.The correct and appropriate initial treatment of associated urethral rupture is critical to the proper healing of the injury.Placing of a suprapubic cystostomy on admission and delayed anastomotic urethroplasty after 3e6 months continues to be the gold standard of treatment.In this paper,we provide a comprehensive review of the literature with a special emphasis on the various treatments available:Open or endoscopic primary realignment,immediate or delayed urethroplasty after suprapubic cystostomy,and delayed optical urethrotomy.展开更多
The recent International Consultation on Urological Disease(ICUD)panel 2010 confirmed that a urethral stricture is defined as a narrowing of the urethra consequent upon ischaemic spongiofibrosis,as distinct from sphin...The recent International Consultation on Urological Disease(ICUD)panel 2010 confirmed that a urethral stricture is defined as a narrowing of the urethra consequent upon ischaemic spongiofibrosis,as distinct from sphincter stenoses and a urethral disruption injury.Whenever possible,an anastomotic urethroplasty should be performed because of the higher success rate as compared to augmentation urethroplasty.There is some debate currently regarding the critical stricture length at which an anastomotic procedure can be used,but clearly the extent of the spongiofibrosis and individual anatomical factors(the length of the penis and urethra)are important,the limitation for this being extension of dissection beyond the peno-scrotal junction and the subsequent production of chordee.More recently,there has been interest in whether to excise and anastomose or to carry out a stricturotomy and reanastomosis using a Heineke-Miculicz technique.Augmentation urethroplasty has evolved towards the more extensive use of oral mucosa grafts as compared to penile skin flaps,as both flaps and grafts have similar efficacy and certainly the use of either dorsal or ventral positioning seems to provide comparable results.It is important that the reconstructive surgeon is well versed in the full range of available repair techniques,as no single method is suitable for all cases and will enable the management of any unexpected anatomical findings discovered intra-operatively.展开更多
Penile fractures are an uncommon urological emergency.Typically,penile fractures involve the corpus cavernosum and are sometimes associated with urethral injury.Isolated corpus spongiosum and urethral injuries without...Penile fractures are an uncommon urological emergency.Typically,penile fractures involve the corpus cavernosum and are sometimes associated with urethral injury.Isolated corpus spongiosum and urethral injuries without concomitant corpus cavernosum injury are,however,rare.With proper knowledge of the management of penile fractures and urethral injuries,this distinct entity can be diagnosed,assessed and managed successfully without complications.展开更多
Objectives:To assess the effect of redo inferior pubectomy on the management of complicated pelvic fracture urethral injury(PFUI)in patients with a history of failed anastomotic urethroplasty.Materials and methods:We ...Objectives:To assess the effect of redo inferior pubectomy on the management of complicated pelvic fracture urethral injury(PFUI)in patients with a history of failed anastomotic urethroplasty.Materials and methods:We retrospectively reviewed all patients receiving redo anastomotic urethroplasty with redo inferior pubectomy for failed PFUI between January 2010 and December 2021.Patients with incomplete data and those who were lost to follow-up were excluded.Successful urethroplasty was defined as the restoration of a uniform urethral caliber without stenosis or leakage and further intervention.Functional results,including erectile function and urinary continence,were evaluated.Descriptive statistical analyses were then performed.Results:Thirty-one patients were included in this study.Among them,concomitant urethrorectal fistula occurred in 2 patients,and concomitant enlarged bladder neck occurred in 1.The stenosis site was the bulbomembranous urethra in 2 patients and the prostatomembranous urethra in 29.The mean length of urethral stenosis in all patients was 3.1 cm(range,2.0-5.0 cm).After a mean follow-up of 34.6 months,the final success rate was 96.8%.The incidence of erectile dysfunction reached 77.4%(24/31).Normal continence was achieved in 27(87.1%)patients.One patient developed urinary incontinence of gradeⅡrequiring urinary pads because of an enlarged bladder neck.According to the Clavien-Dindo classification,postoperative complications of grade I occurred in 7 patients and gradeⅡin 4.Conclusions:Repeat anastomotic urethroplasty with repeat inferior pubectomy provides reliable success rates for failed PFUI.In complicated cases,it should be known and mastered.展开更多
BACKGROUND Trauma is a major cause of morbidity globally and the sixth leading cause of death,accounting for 10%of all mortalities.The genitourinary trauma is estimated for approximately 10%of all patients presenting ...BACKGROUND Trauma is a major cause of morbidity globally and the sixth leading cause of death,accounting for 10%of all mortalities.The genitourinary trauma is estimated for approximately 10%of all patients presenting with trauma,and the kidney is the most injured genitourinary organ globally.However,there is a paucity of data on genitourinary injury from the Sub-Saharan,and there may be variations from common genitourinary organs injured in developed nations.AIM To provide insight on the epidemiology and management of genitourinary trauma in Sub-Saharan Africa with recommendations based on international guidelines.METHODS A thorough literature search of genitourinary trauma was conducted using PubMed,Google Scholar and African Journal Online.RESULTS A total of 30 studies from the Sub-Saharan region were eligible for the study and reviewed for epidemiology,biodata,types of injury,mechanisms of injury,treatment and follow-up.After evaluating 21904 patients presenting with urological emergencies,approximately 6.6%of cases were due to genitourinary trauma.The commonest injury was urethral 42.9%(22.2-62.2%)followed by injury to the external genitalia(penis,scrotum,testes)25.1%(8.8-67.7%).CONCLUSION Genitourinary injury in Sub-Saharan Africa is underreported,and the presence of more trauma registries,trained urologists and trauma facilities could improve the overall standard of care as well as providing data for research and development in the field.展开更多
A locked pubic ramus body is an unusual variant of lateral compression injury.Till date,there have been only 25 cases reported in the published literature.We herein described a case where the right pubic ramus was ent...A locked pubic ramus body is an unusual variant of lateral compression injury.Till date,there have been only 25 cases reported in the published literature.We herein described a case where the right pubic ramus was entrapped within the opposite obturator foramen with an overlap of greater than 4 cm,with associated urethral injury.When all maneuvers of closed and instrumented reduction failed,we per-formed a superior pubic ramus osteotomy on the left side and unlocked the incarcerated right pubic ramus.The osteotomy site was stabilized with a 6-hole recon plate.The patient underwent delayed urethral repair 10 weeks after the index surgery.At 3-year follow-up,the patient has sexual dysfunction especially difficulty in maintaining erection,secondary urethral stricture,heterotopic ossification,and breakage of implants.展开更多
Background:Although urethral trauma may lead to serious consequences if mismanaged,treatment concepts are inconsistent.We designed a survey to investigate the current diagnosis and management of emergency blunt urethr...Background:Although urethral trauma may lead to serious consequences if mismanaged,treatment concepts are inconsistent.We designed a survey to investigate the current diagnosis and management of emergency blunt urethral trauma to aid future dissemination of relevant concepts.Methods:A 15‐item anonymous questionnaire was distributed via an online platform.It addressed items such as the cognition of how to diagnose of urethral trauma,optimal emergency management of a urethral trauma patient,and attitude towards early realignment for pelvic fracture urethral injuries.Results:Of 538 respondents,94.2%and 84.9%had received patients with straddle trauma urethral injuries or pelvic fracture urethral injuries,respectively,within the past year.In the emergency room,attempted urethral catheterization was the most selected examination method by respondents for diagnosis of both straddle injury(500/538)and pelvic fracture urethral injury(469/538).For patients with straddle injury,41.3%of respondents performed endoscopic realignment and 31.6%preferred suprapubic cystostomy.For hemodynamically stable patients with PFUI,42.2%of respondents preferred suprapubic cystostomy and 34.9%preferred endoscopic realignment.Most respondents felt favorably toward early realignment for pelvic fracture urethral injuries.After realignment,61.3%,24.5%,and 13.8%of respondents performed catheterization for 4,8,and 12 weeks,respectively.Further,54.6%of respondents believed catheter traction should be applied after realignment.Conclusion:Although the number of yearly emergency urethral trauma cases was small,the opinions and practices of most urologists were consistent with guidelines.However,the significance of retrograde urethrography was not fully understood,and some respondents had incorrect views on catheter traction after realignment.展开更多
Penile fracture(PF)is a surgical emergency.Given its rarity,we queried a national cohort over an 11-year period to study the temporal and demographic variations in presentation,evaluation,and management of patients wi...Penile fracture(PF)is a surgical emergency.Given its rarity,we queried a national cohort over an 11-year period to study the temporal and demographic variations in presentation,evaluation,and management of patients with PF compared with a cohort of control patients.The National Inpatient Sample was queried between the years 2005 and 2016 for patients with a diagnosis of PF.Appendectomy patients were selected as a control cohort,given the non-discriminatory nature of this disease.Clinical and demographic data of the patients were compared with that of controls.Presenting symptoms,rates of surgical repair,and rates of associated surgical procedures were evaluated in the PF cohort.During the study period,5802 patients were hospitalized for PF.The annual incidence of PF remained unchanged at 1.0-1.8 cases per 100000 hospitalizations over the study period.Compared with the control cohort,PF patients were more likely to be younger(38.7 years vs 41.2 years,P≤0.001),have lower rates of comorbidities except erectile dysfunction(1.4%vs 0.1%,P≤0.001),and were more likely of Black race(25.4%vs 6.2%,P≤0.001).Notably,PF patients had significantly higher rates of substance abuse(26.4%vs 18.1%,P≤0.001),despite no difference in the diagnosed psychiatric disorders.PF rarely presented with hematuria(3.5%);however,urethral evaluation was performed in 23.1%,most commonly with cystoscopy(19.2%).PF occurs more commonly in a younger,healthier male population,and among minorities.Importantly,rates of substance abuse appear to be higher in the PF cohort compared with those of controls.展开更多
文摘Objectives:Pelvic fracture urethral injuries(PFUI)result from traumatic disruption of the urethra.A significant proportion of cases are complex rendering their management challenging.We described management strategies for eight different complex PFUI scenarios.Methods:Our centre is a tertiary referral centre for complex PFUI cases.We maintain a prospective database(1995e2016),which we retrospectively analysed.All patients with PFUI managed at our institute were included.Results:Over two decades 1062 cases of PFUI were managed at our institute(521 primary and 541 redo cases).Most redo cases were referred to us from other centres.Redo cases had up to five prior attempts at urethroplasty.We managed complex cases,which included bulbar ischemia,young boys and girls with PFUI,PFUI with double block,concomitant PFUI and iatrogenic anterior urethral strictures.Bulbar ischemia merits substitution urethroplasty,most commonly,using pedicled preputial tube.PFUI in young girls is usually associated with urethrovaginal fistula.Young boys with PFUI commonly have a long gap necessitating trans-abdominal approach.Our success rate with individualised management is 85.60%in primary cases,79.13%in redo cases and 82.40%in cases of bulbar ischemia.Conclusion:The definition of complex PFUI is ever expanding.The best chance of success is at the first attempt.Anastomotic urethroplasty for PFUI should be performed in experienced hands at high volume centres.
文摘BACKGROUND A male urethral disruption injury is a urological emergency.Primary endoscopic realignment(PER)refers to reestablishment of urethral alignment via indwelling urethral catheter by cystoscope,which is recommended as the optimal emergent treatment approach for reducing the likelihood of complications following injury.However,the prior literature suggests the success rate of PER to be relatively low due to complicated urethral disruption.We report a modified PER approach that serves to improve both the success rate and safety of the treatment.CASE SUMMARY A 19-year-old male patient presented with multiple pelvic fractures and complete urethral disruption following a high-velocity traffic accident.The patient’s abdominal computed tomography and retrograde urethrography results revealed complete urethral disruption at the bulbar urethra,with hematoma and contrast medium extravasation that extended into the extraperitoneal space.The conventional retrograde PER by cystoscope failed due to severe disruption and considerable hematoma.Modified simultaneous antegrade and retrograde PER was performed by means of semi-rigid ureteroscopy via a suprapubic Foley catheter and cystoscopy via the external urethra.An antegrade guidewire was passed through the bladder neck and then pulled out through the external urethral meatus with a cystoscope.Urethral continuity was achieved after a 16-Fr silicone Foley catheter was indwelled into the bladder along the guidewire.The patient recovered well,achieving voiding continence and avoiding further operation for urethral stricture.CONCLUSION Modified PER via suprapubic Foley catheter represents a promising and safe treatment approach in patients with posterior urethral injuries.
文摘Posterior urethral injuries typically arise in the context of a pelvic fracture.Retrograde urethrography is the preferred diagnostic test in trauma patients with pelvic fracture where a posterior urethral rupture is suspected.Pelvic fractures however preclude the adequate positioning of the patient on the X-ray table on admission and computed tomography scan with intravenous contrast and delayed films generally performed first.Suprapubic bladder catheter placement under ultrasound guidance should be performed whenever a posterior urethral disruption is suspected.Early diagnosis and proper acute management decrease the associated complications,such as strictures,urinary incontinence and erectile dysfunction.The correct and appropriate initial treatment of associated urethral rupture is critical to the proper healing of the injury.Placing of a suprapubic cystostomy on admission and delayed anastomotic urethroplasty after 3e6 months continues to be the gold standard of treatment.In this paper,we provide a comprehensive review of the literature with a special emphasis on the various treatments available:Open or endoscopic primary realignment,immediate or delayed urethroplasty after suprapubic cystostomy,and delayed optical urethrotomy.
文摘The recent International Consultation on Urological Disease(ICUD)panel 2010 confirmed that a urethral stricture is defined as a narrowing of the urethra consequent upon ischaemic spongiofibrosis,as distinct from sphincter stenoses and a urethral disruption injury.Whenever possible,an anastomotic urethroplasty should be performed because of the higher success rate as compared to augmentation urethroplasty.There is some debate currently regarding the critical stricture length at which an anastomotic procedure can be used,but clearly the extent of the spongiofibrosis and individual anatomical factors(the length of the penis and urethra)are important,the limitation for this being extension of dissection beyond the peno-scrotal junction and the subsequent production of chordee.More recently,there has been interest in whether to excise and anastomose or to carry out a stricturotomy and reanastomosis using a Heineke-Miculicz technique.Augmentation urethroplasty has evolved towards the more extensive use of oral mucosa grafts as compared to penile skin flaps,as both flaps and grafts have similar efficacy and certainly the use of either dorsal or ventral positioning seems to provide comparable results.It is important that the reconstructive surgeon is well versed in the full range of available repair techniques,as no single method is suitable for all cases and will enable the management of any unexpected anatomical findings discovered intra-operatively.
文摘Penile fractures are an uncommon urological emergency.Typically,penile fractures involve the corpus cavernosum and are sometimes associated with urethral injury.Isolated corpus spongiosum and urethral injuries without concomitant corpus cavernosum injury are,however,rare.With proper knowledge of the management of penile fractures and urethral injuries,this distinct entity can be diagnosed,assessed and managed successfully without complications.
基金supported by the National Natural Science Foundation of China(no.82100707 and 82270707)Shanghai Municipal Health Commission research project(no.202140191).
文摘Objectives:To assess the effect of redo inferior pubectomy on the management of complicated pelvic fracture urethral injury(PFUI)in patients with a history of failed anastomotic urethroplasty.Materials and methods:We retrospectively reviewed all patients receiving redo anastomotic urethroplasty with redo inferior pubectomy for failed PFUI between January 2010 and December 2021.Patients with incomplete data and those who were lost to follow-up were excluded.Successful urethroplasty was defined as the restoration of a uniform urethral caliber without stenosis or leakage and further intervention.Functional results,including erectile function and urinary continence,were evaluated.Descriptive statistical analyses were then performed.Results:Thirty-one patients were included in this study.Among them,concomitant urethrorectal fistula occurred in 2 patients,and concomitant enlarged bladder neck occurred in 1.The stenosis site was the bulbomembranous urethra in 2 patients and the prostatomembranous urethra in 29.The mean length of urethral stenosis in all patients was 3.1 cm(range,2.0-5.0 cm).After a mean follow-up of 34.6 months,the final success rate was 96.8%.The incidence of erectile dysfunction reached 77.4%(24/31).Normal continence was achieved in 27(87.1%)patients.One patient developed urinary incontinence of gradeⅡrequiring urinary pads because of an enlarged bladder neck.According to the Clavien-Dindo classification,postoperative complications of grade I occurred in 7 patients and gradeⅡin 4.Conclusions:Repeat anastomotic urethroplasty with repeat inferior pubectomy provides reliable success rates for failed PFUI.In complicated cases,it should be known and mastered.
文摘BACKGROUND Trauma is a major cause of morbidity globally and the sixth leading cause of death,accounting for 10%of all mortalities.The genitourinary trauma is estimated for approximately 10%of all patients presenting with trauma,and the kidney is the most injured genitourinary organ globally.However,there is a paucity of data on genitourinary injury from the Sub-Saharan,and there may be variations from common genitourinary organs injured in developed nations.AIM To provide insight on the epidemiology and management of genitourinary trauma in Sub-Saharan Africa with recommendations based on international guidelines.METHODS A thorough literature search of genitourinary trauma was conducted using PubMed,Google Scholar and African Journal Online.RESULTS A total of 30 studies from the Sub-Saharan region were eligible for the study and reviewed for epidemiology,biodata,types of injury,mechanisms of injury,treatment and follow-up.After evaluating 21904 patients presenting with urological emergencies,approximately 6.6%of cases were due to genitourinary trauma.The commonest injury was urethral 42.9%(22.2-62.2%)followed by injury to the external genitalia(penis,scrotum,testes)25.1%(8.8-67.7%).CONCLUSION Genitourinary injury in Sub-Saharan Africa is underreported,and the presence of more trauma registries,trained urologists and trauma facilities could improve the overall standard of care as well as providing data for research and development in the field.
文摘A locked pubic ramus body is an unusual variant of lateral compression injury.Till date,there have been only 25 cases reported in the published literature.We herein described a case where the right pubic ramus was entrapped within the opposite obturator foramen with an overlap of greater than 4 cm,with associated urethral injury.When all maneuvers of closed and instrumented reduction failed,we per-formed a superior pubic ramus osteotomy on the left side and unlocked the incarcerated right pubic ramus.The osteotomy site was stabilized with a 6-hole recon plate.The patient underwent delayed urethral repair 10 weeks after the index surgery.At 3-year follow-up,the patient has sexual dysfunction especially difficulty in maintaining erection,secondary urethral stricture,heterotopic ossification,and breakage of implants.
文摘Background:Although urethral trauma may lead to serious consequences if mismanaged,treatment concepts are inconsistent.We designed a survey to investigate the current diagnosis and management of emergency blunt urethral trauma to aid future dissemination of relevant concepts.Methods:A 15‐item anonymous questionnaire was distributed via an online platform.It addressed items such as the cognition of how to diagnose of urethral trauma,optimal emergency management of a urethral trauma patient,and attitude towards early realignment for pelvic fracture urethral injuries.Results:Of 538 respondents,94.2%and 84.9%had received patients with straddle trauma urethral injuries or pelvic fracture urethral injuries,respectively,within the past year.In the emergency room,attempted urethral catheterization was the most selected examination method by respondents for diagnosis of both straddle injury(500/538)and pelvic fracture urethral injury(469/538).For patients with straddle injury,41.3%of respondents performed endoscopic realignment and 31.6%preferred suprapubic cystostomy.For hemodynamically stable patients with PFUI,42.2%of respondents preferred suprapubic cystostomy and 34.9%preferred endoscopic realignment.Most respondents felt favorably toward early realignment for pelvic fracture urethral injuries.After realignment,61.3%,24.5%,and 13.8%of respondents performed catheterization for 4,8,and 12 weeks,respectively.Further,54.6%of respondents believed catheter traction should be applied after realignment.Conclusion:Although the number of yearly emergency urethral trauma cases was small,the opinions and practices of most urologists were consistent with guidelines.However,the significance of retrograde urethrography was not fully understood,and some respondents had incorrect views on catheter traction after realignment.
文摘Penile fracture(PF)is a surgical emergency.Given its rarity,we queried a national cohort over an 11-year period to study the temporal and demographic variations in presentation,evaluation,and management of patients with PF compared with a cohort of control patients.The National Inpatient Sample was queried between the years 2005 and 2016 for patients with a diagnosis of PF.Appendectomy patients were selected as a control cohort,given the non-discriminatory nature of this disease.Clinical and demographic data of the patients were compared with that of controls.Presenting symptoms,rates of surgical repair,and rates of associated surgical procedures were evaluated in the PF cohort.During the study period,5802 patients were hospitalized for PF.The annual incidence of PF remained unchanged at 1.0-1.8 cases per 100000 hospitalizations over the study period.Compared with the control cohort,PF patients were more likely to be younger(38.7 years vs 41.2 years,P≤0.001),have lower rates of comorbidities except erectile dysfunction(1.4%vs 0.1%,P≤0.001),and were more likely of Black race(25.4%vs 6.2%,P≤0.001).Notably,PF patients had significantly higher rates of substance abuse(26.4%vs 18.1%,P≤0.001),despite no difference in the diagnosed psychiatric disorders.PF rarely presented with hematuria(3.5%);however,urethral evaluation was performed in 23.1%,most commonly with cystoscopy(19.2%).PF occurs more commonly in a younger,healthier male population,and among minorities.Importantly,rates of substance abuse appear to be higher in the PF cohort compared with those of controls.