0:00 Hello, in this video, we're going to talk about anal fistula, or fistula in 0:10 anal. 0:10 So fistula in anal is a tunnel that connects an internal opening, usually at 0:16 the anal crypts 0:18 at the base of the column of Mugani, to the peri anal skin, which is the 0:26 external opening. 0:26 Just to be clear, a fistula is a connection between one epithelial layer to 0:32 another epithelial 0:34 layer. 0:36 Let us now revise the normal anal rectal anatomy first. 0:41 So in the anal rectal anatomy, the anus, there are muscles that surround it. 0:47 There is the internal anal sphinctum, which is a muscle controlled invol 0:52 untarily, and the 0:53 surrounding external anal sphinctum, which is under voluntary control. 0:58 It is important to know these muscles, because they play a role in naming the 1:02 different types 1:03 of fistulas that are found in the area. 1:07 The levatorana is another group of muscles that make up the pelvic floor, the 1:12 diaphragm, 1:13 and these muscles are important in the rectal tone. 1:17 An important landmark to know is the pectinate line, also known as the dentate 1:22 line. 1:23 This anatomical landmark passes sort of through the anal crypts. 1:28 Now cells below the pectinate line are ectodermine origin. 1:33 These cells are like our skin, which are highly sensitive. 1:37 And so pain that occurs here are well localized and sharp. 1:43 The digestive organs, itself as we know, are covered by visceral peritoneum. 1:48 Another anatomically important structure are the internal and external hemorrh 1:54 oid plexi, 1:55 which are normal venous plexus located in the anal area. 2:03 Fistula can occur in the anal area, and can cause some serious discomfort. 2:10 There are many types of fistulas in anal, and this really depends on where they 2:15 are localized, 2:16 where they travel to and where they travel from. 2:20 They are named actually in relationship to the sphinteric muscles, most of the 2:26 time. 2:27 So for example, intersphinteric fistula travels from the anal canal in between 2:33 the internal 2:35 and external sphinter muscles to an opening. 2:38 A fistula that travels from the internal opening, which is the anal canal, and 2:44 travels above 2:45 the sphinteric muscles and down to an external opening is called a suprac sph 2:51 interic fistula, 2:52 which makes sense. 2:54 A fistula that travels from the internal opening, which is the anal canal, 2:58 travels through the 2:59 internal and the external anal sphinteric muscles to an external, um, anal 3:06 opening. 3:06 The peri anal opening is called a transphinteric fistula, so trans as an across 3:12 . 3:12 And finally, a fistula that does not involve the sphinteric at all is called an 3:17 extra sphinteric 3:17 fistula. 3:20 Fistula can cause mild to severe discomfort. 3:24 The signs and symptoms include peri anal abscess, that is not healing. 3:30 This is because peri anal abscess are the main cause of fistulas. 3:36 It can also be pain, pruritis, and intermittent or constant porelet discharge 3:42 from the peri 3:43 anal opening. 3:51 On examination it is important to perform a rectal examination, which involves 3:55 general 3:55 inspection and use of a proctoscope or anoscope. 4:00 Another interesting thing to note is what's known as the good cell salman's law 4:05 , which 4:06 in basic terms, it's a principle or a law that says that if you draw a 4:12 horizontal line 4:13 essentially through the anal opening, an external fistula opening anterior to 4:21 the line is a 4:22 straight fistula. 4:25 And a fistula opening below or posterior sorry to the line is a curved fistula. 4:32 An external fistula opening anterior to the line is a straight fistula. 4:40 And a fistula opening below or posterior sorry to the line is a curved fistula. 4:47 However, there is another rule in that if the external opening that is anterior 4:52 to the 4:52 line is actually 3 centimeters away from the anal opening, this is also a 5:00 curved fistula. 5:02 Not sure how helpful this law is clinically, but thought it was interesting. 5:09 Essentially in examination what wants to be done is that we want to identify 5:14 the external 5:15 opening through the general observation and then identify an external opening 5:21 using a 5:22 proctoscope. 5:24 Diagnosis is history and examination including presence of pain, purling 5:30 discharge and parorectal 5:31 skin lesion. 5:36 Differential diagnoses include anal ulcers or anal sores, usually associated 5:42 with Crohn's 5:43 disease which is an inflammatory bowel disease. 5:48 Another differential diagnosis is an anal fissure. 5:52 And finally anal abscess. 5:57 The etiology of anal fistula is mainly anal abscess as mentioned earlier 6:03 because what happens 6:04 is the abscess will spread through areas of least resistance within the peri 6:11 anal area 6:12 and so can create a tunnel. 6:16 Another cause is Crohn's disease, 30% of Crohn's patients is said to experience 6:22 anal 6:22 fistula. 6:25 This is one of the complications of Crohn's disease and can occur with or 6:28 without anal 6:29 abscess. 6:32 The management of fistula is surgical and can be divided into surgery for 6:38 simple or surgery 6:39 for complex fistula. 6:41 Let's focus on the simple fistula first. 6:45 Simple fistula surgery involves a fistulotomy. 6:49 In summary, a scope is used to open the anus. 6:54 A probe is inserted through the fistula, this shows the fistula root. 7:00 Then a cut is made along the track. 7:08 This is followed by stitching it up and this process aims to create a local 7:13 inflammatory 7:13 reaction which is then followed by a healing reaction. 7:17 However, in complex fistula, a fistulotomy and cetron is used which is a 7:24 similar procedure 7:26 in that a probe is used and passed through the fistula. 7:31 Then a suture is also passed through, the suture is tied up and in regular 7:37 intervals it is 7:38 tightened. 7:40 This means the person has to come to the doctor to get it tightened up 7:44 regularly. 7:44 The aim is that as the suture is tightened, it will slowly cut an opening but 7:50 the cut 7:50 opening will then be followed by a wound healing process. 7:56 Another procedure that can be done for complex fistula is a fistula plug. 8:01 Another procedure that can be done for complex fistula is a fistula plug. 8:07 The fistula itself is firstly cleaned and irrigated. 8:11 Then a suture or thread is passed through the fistula with a plug at the end of 8:16 it. 8:17 The aim is to pull the plug into the fistula through the internal opening. 8:23 The plug is then tied down into the anal opening. 8:28 The external opening of the fistula is actually left open to allow drainage of 8:34 the fistula. 8:36 The final procedure I will talk about is the advancement flat procedure. 8:41 This is where a probe again is passed through the fistula to identify the tract 8:46 . 8:47 A larger cut is made in the external opening for the fistula to be cleaned. 8:52 A large incision is made partly around the internal fistula opening. 8:58 This cut is shaped like a flap which is then excised and moved forward over the 9:05 internal 9:06 opening. 9:07 The flap will close the internal fistula opening with the absorbable sutures 9:12 and this will all 9:13 heal up.
