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testicular torsion occurs when a testis twists the spermatic cord resulting in cutting off of blood supply .
the extension of testicular ischemia depends on the degree of twisting ( 180 - 720 ) and duration of the torsion .
testicular salvage mostly happens in those who are treated within 4 - 6 hours after the onset of torsion .
tt accounts for at least up to 26% of cases of acute scrotum ( 1 ) , but beni - israel et al . reported it even from 17 - 72% ( 2 ) .
anatomically there are two types of testicular torsion which occur in different age groups : 1 ) extra - vaginal ( supra - vaginal ) : torsion occurs at the level of the external inguinal ring , which is seen in neonates .
2 ) intra - vaginal : a more common variety due to bell clapper deformity that typically occurs in adolescents and young adults . typically , sudden onset of severe pain followed by inguinal / scrotal swelling and nausea or vomiting is the most common symptom of tt ( 2 - 5 ) .
cdu and high - resolution ultrasonography are the modality of choice for diagnosis of scrotal disorders in children , and near infrared spectroscopy is a novel diagnostic approach ( 1 , 6 , 7 ) . early surgical exploration is recommended by most authors in acute scrotum to prevent or confirm torsion ( 8 , 9 ) .
when the diagnosis of tt is established , the surgeon faces another dilemma , i.e. whether or not to remove the testis ; here only surgical exploration can make the decision .
there are many studies about tt but no experience in second look exploration to be compared with .
in recent study we have performed combination of early exploration , and second - look operation only in our 70 cases .
in a historical cohort study 70 boys out of 124 patients underwent early exploration and 48 hours later second look exploration due to tt in mofid children s hospital from january 2008 to december 2013 .
fifty four cases of tt which were explored in one stage only , and neonatal torsions were excluded from the study .
after color - doppler ultrasonography ( cdu ) and necessary lab tests , emergency surgical exploration was performed in included 70 cases and after intraoperative bleeding test , this group of patients underwent second look exploration after 48 hours .
evaluation of bleeding test : when tunica albuginea is incised , the onset of active arterial bleeding ( bright blood ) from the cut edge : grade i : immediate bleeding after incision .
all patients were followed - up , and checked by high - resolution ultrasonography and cdu every 3 months .
data included age at admission , side of pathology , relation of tt with season of year , duration of preoperative history , degree of testicular torsion , cdu findings , and degree of bleeding , results of second look exploration , follow - up , and outcomes were analyzed , and descriptive statistical analysis was performed by spss 16 software .
totally 70 patients were included in this study within five years , with a mean age of 28.6  32.9 ( range 1 to 144 ) months , 48% of our patients had nausea and vomiting .
orchidopexy was performed in 44 ( 63% ) and orchidectomy in 26 ( 37% ) cases after second look exploration .
table 1 shows the duration of symptoms before surgery , intraoperative arterial bleeding test of patients in first exploration and degree of torsion in our cases .
4 cases ( 9% ) in orchidopexy group developed testicular atrophy during follow - up ; of these , blood flow was absent in one ( 25% ) and weak in the other ( 75% ) on preoperative cdu .
all four cases had a history of longer than 12 hours and grade ii testicular bleeding test intra - operatively .
26 patients , who were in grade iii , underwent orchidectomy in second look exploration .
cold season , degree higher than 360 and a history longer than 12 hour were not specific signs of testicular non - viability .
sensitivity , specificity , ppv and npv of variables are shown in table 2 .  
tt torsion is an emergency condition with risk of irreversible ischemic injury if not promptly treated .
it is caused by the torsion of the spermatic cord within the space of the tunica vaginalis in children and adolescents .
it may result due to lack of normal fixation of testis or epididymis to the facial and muscular layers of cord or scrotum .
tt accounts for only about 20 - 25% of all cases of acute scrotum in children ( 11 ) .
( 12 ) reported 19 tt with median age of 10 ( range 0 - 15 ) years , in our research mean age was 28 ( range 1 - 144 ) months .
incidence of nausea and vomiting in our study was 48% , and in mellick ( 13 ) it was 32% .
the incidence of tt is more common in left side , as it was 74% in our patients , and 63% in boettcher et al .
duration of symptoms before surgery is an important predictor of outcome in tt ( 14 ) .
jefferson et al . ( 15 ) reported that no testicle with a history longer than 12 hours could be salvaged .
other researchers ( 11 ) observed testicular necrosis , even atrophy after orchidopexy in patients with the history shorter than 10 hour .
( 14 ) reported testicular atrophy during follow - up in 27% of patients after orchidopexy within 4 hours of onset of symptoms . in our study 63% of tt of which
47% lasted shorter than 12 hour , and 16% longer than 12 hour were salvaged after second look exploration .
barbalias and liatsikos ( 16 ) have reported testicular salvage more than 24 hour after onset of symptoms .
17 ) reported that in boys whose torsed testis was salvaged the pain was present for averagely 20 hours .
10 ) , and mellick ( 13 ) found that there is no significant difference in tt with rotation degree of 360 to those with more than 360 degree . in our patients
series orchidopexy was performed in 20 cases which had more than 360 ( 360 - 540 ) degree and of which 16 were salvaged .
testis in high and transverse position , thickening of epididymis , retractile testis , and some times lack of the cremasteric reflex can cause tt ( 2 , 13 , 18 , 19 ) .
( 20 ) believe that a lack of the cremasteric reflux is another feature highly associated with tt , and was effective as a predictor in half of their patients .
( 21 ) reported that twisted testis can be detected 96% by high - resolution ultrasonography , and 76% by cdu ( 22 ) .
preoperative cdu showed absent / weak flow in 50 cases in recent study . during surgical exploration , a deep incision of the tunica albuginea after detorsion to evaluate active bleeding within 10 minutes is mandatory .
arda and ozyaylali ( 23 ) believe that this test is an effective means to assess objectively testicular viability during surgery .
we performed this test in all cases , of which in orchidopexy group 20 cases were in grade i and 24 in grade ii , but all orchidectomy groups were in grade iii .
cimador et al . reported two cases of testicular atrophy in their follow - up within orchidopexy group , and we had only four cases within our follow - up .
( 24 ) reported a higher number of tt during colder months , with a significant increase during winter . in recent study of 70 cases with tt , 31 ( 44% ) were in winter season , and 22 ( 31% ) patients referred during autumn season . early diagnosis and exploration
imaging / radionuclide scanning should not be a cause of delay , also ultrasonography may produce false negative results , so early surgical exploration is mandatory , and second look exploration can be more effective in salvageability .
cold season , torsion degree higher than 360 and a history longer than 12 hours were not specific signs of testicular non - viability .
the school age group which is the most vulnerable one , should be informed about his topic to prevent testicular damage .
background : testicular torsion ( tt ) , or twisting of the testicle resulting in a strangulation of the blood supply , occurs in men whose tissue surrounding the testicle is not well attached to the scrotum . 
 it is important to emphasize that testicular torsion is a medical emergency.objectives:the aim of this study is to evaluate the second look exploration and outcomes in tt.patients and methods : seventy boys out of 124 patients underwent early exploration and 48 hours later second look exploration due to tt . 
 all patients were checked with preoperative color - doppler ultrasonography ( cdu ) and intraoperative bleeding test . 
 data included age at admission , side of pathology , relation of tt with season of year , duration of preoperative history , degree of testicular torsion , cdu findings , and degree of bleeding ; results of second look exploration , follow - up , and outcomes were analyzed.results:totally 70 patients were included in this study within five years , of which mean age was 28.6  32.9 months ( range 1 to 144 ) , 48% of our patients had nausea and vomiting . 
 preoperative cdu showed absent / weak flow in 50 ( 71% ) cases . 
 winter showed most frequently ( 44% ) referred cases of testicular torsion . 
 orchidopexy was performed in 44 ( 63% ) and orchidectomy in 26 ( 37% ) cases after second look exploration . 
 mean follow - up duration was 3.1  1.4 years . 
 4 ( 9% ) cases in orchidopexy group developed testicular atrophy during follow - up , all four cases had a history of longer than 12 hours and grade ii testicular bleeding test intra - operatively . 
 other orchidopexy patients salvaged . 
 26 patients , who were in grade iii , underwent orchidectomy in second look exploration.conclusions:tt requires emergency attention . 
 the ischemia time of the testis is traditionally after 6 hours , and imaging or other diagnostic modality should not be a cause of delay . 
 early surgical exploration is modality of choice , and second look exploration after 48 hours can be more effective and salvageable in these patients .