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Grand Rounds-The Oral Boards Part I: Pearls for Success and Review Cases

William Couldwell

July 24, 2011


- Hello, ladies and gentlemen, thank you for joining us. The Oral Boards is a special event in all of our careers, we therefore thought it will be reasonable to dedicate a session to the topic. We're happy to have with us today, Dr. Bill Couldwell, who is the Head of the Oral Board Subcommittee of the American Board of Neurological Surgery. Bill, thank you for joining us.

- Welcome Aaron. It's a pleasure to be here and talk about the format and the scoring of the oral exam. So this is the current format in scoring of the exam, we've been making changes over the past few years, but all of the candidates that we'll be examining will have completed a neurosurgical residency program approved by the RRC of the ACGME. They will have passed for credit written primary examination during the residency, and they must submit an application within five years of completing the residency. They will have submitted 150 cases of operative data reviewed and approved by a board member and also submitted letters of recommendation, evidence of licensure and current hospital appointments. So the format of the exam, is that there's three, one hour sessions, and in each of these sessions, there'll be two examiners. One examiner will be an ABNS director, a current director or a former director, and the other one will be a guest examiner, and they'll be asking alternating clinical vignettes to the candidate. The topics covered will be as listed, spine and spinal cord, perhaps peripheral nerve in that section as well, cranial, extracranial vascular, critical care, neurology, pediatric neurosurgery, functional surgery and pain surgery, and peripheral nerve surgery. So the examiners have been specifically instructed to avoid humorous or aggressive comments. They will not attempt to correct or teach or provide no feedback or verbal clues as to whether the answer that they've been given is correct. We won't dwell on weaknesses or strengths and we'll move on to other topics. And we won't ask trick questions or ask for any didactic material. Actual clinical encounters are simulated during the exam, not like a written exam, and there'll be patients presenting in the ER, for an office visit, being seen in the ICU and OR simulations, et cetera. Candidates will actually participate in the process, so it'll be an interactive process and you'll ask for the data needed to solve the problems presented. And the candidates are expected to provide rationale for their decisions so we may ask you, why did you do it this way? And as long as you have a reasonable rationale, that is acceptable. So the typical format is that there'll be oral presentation of the patient's history and the physical examination findings. The pertinent test results and images will be presented, the candidate will be asked to propose a differential diagnosis in order of priority. They'll be asked to initially manage the patient, including the medical management, surgical planning, if so indicated and specifics about the surgical procedure, including incision, location, flaps, operative technique, and interoperative complications, maybe given. And then there'll be asked also a comment on postoperative management in the appropriate scenario. So we ask a minimum of six questions per hour in each of the hours. So we'll move on to the next question if the candidate is stumped and an oral exam is not centered on interpreting images, but you need to understand that you need to be able to interpret the appropriate images to make surgical decision-making in the absence of a radiology interpretation. So extensive radiological interpretation of the examination will not be tested, but we'll expect you to make a straightforward management decisions. We want you to focus on judgment and be open to alternative solutions. So there's many different ways of handling problems, we understand that and the examiners are instructed to be open-minded to this. The exam is comprehensive and so the candidates should be able to answer all questions regarding the entire spectrum of neurosurgical diseases, despite their subspecialization. And the sort of metric that we use is whether this candidate would be safe to cover an emergency room and to do routine consults in a community hospital. So the grading of the examination. Each of the clinical vignettes, each of the six vignettes that you get during the hour will be graded for three separate tasks. The first is making an appropriate diagnosis, which includes a differential diagnosis, evaluation of examination, history, use the diagnostic test and presentation and physical findings to come up with an appropriate differential diagnosis. Then the next grade will be given for the management, understanding appropriate anatomy, and then if surgery is done how the surgery both technique is performed. And then the third grade is based on a complication that's been given. Now, recognition and handling of complication maybe interoperative, maybe a postoperative complication. And then if it is a disease that requires no surgery and requires their medical therapy, the natural history of the disorder or the outcome will be the basis for the grade. So if you have a surgical case, it'll be based on the complication, if it's a medical case that requires medical management, only the natural history of the disorder will be used to drive this grade. So the rating scale that we use is fairly intuitive, I think everybody's familiar with this, it's a five point scale, it correlates nicely with an A, B, C, D and F grading scale, the higher the grade, the better the score. So each session is graded for the same three tasks, so we make a composite grade for the hour. It's an overall assessment of the candidate, and the grading is dependent on the consideration of the following, are the management plans likely to work? Are there safety issues? And as I mentioned, is the diagnosis and management consistent with expectations for junior hospital staff and sound practice? So after the examination is performed, the grades are extracted into the following three different subject areas. One, spine, two cranial, and three comprehensive other. And so we have three different subspecialty areas, and there's a requirement for all the candidates to pass each of these three subject areas to pass the exam in a comprehensive fashion. So following the examination, there's a discussion period of which the entire group, the examining group, both the directors and the guest examiners discuss marginal candidates. And what I mean by marginal candidates are those candidates that are around the failing grade. Those that are clearly in the failing grade do not get discussed, but those are they're on the cusp, all get discussed. The directors and the guest examiners will point out obviously unfair questions or acceptable answers that were incorrectly graded. There's a presentation of all questions given to those particular candidates and the answers that they gave, so there's a firm understanding of why a candidate did poorly, and what about the responses was a concern and why the grades were given. There is an opportunity then for candidates to have the grades changed based on the appropriate discussion. So ultimately the grades are evaluated by a psychometrician and the ultimate pass point is determined using several different facets. And the ultimate grade given to the candidate is adjusted for the severity of the particular examiner, the severity of the question, and obviously the performance of the candidate. There was no vote on pass or fail, and the computer analysis determines the pass/fail standard subject to board review about two weeks after the exam process and thereafter the candidate is notified. Thank you very much.

- Thank you, Bill, I think this was very helpful in terms of discussing some of the details related to the exam. Would you please mention what are the changes recently during the last exam that was different from the previous sessions of the exams?

- So there's two important changes that we've initiated over the past year. Firstly, the exam used to be subdivided into three separate subject areas. This no longer exists, so there's three equal areas that examine the comprehensive aspects of neurology and neurosurgery. And so in each hour the candidate could be expected to be given a spine question or a neurology question or a cranial question. And secondly, as far as the scoring goes, we've made it mandatory for the candidates to pass each of these three separate subspecialty areas that I mentioned. And so even though they're commingled within the hours, we'll statistically look at each of those subspecialty areas and there'll be a requirement for passing each of those areas to pass the exam in a comprehensive fashion.

- Okay, so in other words, everybody has to be very strong in all the three areas you mentioned to pass the exam, they can't be just strong in two versus three, they have to be strong in all three?

- Right, we did have candidates in the past that were strong in one area and relatively weak in another area. But, again, as I mentioned, the metric that we're trying to use is whether this candidate is safe to cover a comprehensive practice in an emergency room, in a office practice and in a consultative practice.

- Thank you. So I thought maybe I can bring up some questions that would help some of the folks that take the exam further sort of familiarize themselves with the most common questions that people ask. And so today, by the way, this is my disclosure, which does not interfere with the discussion today. I think you very well mentioned all the details Bill, and one of the things that I personally feel people can go wrong pretty quickly is initial management. If you don't have the differential diagnosis, right and you don't know the path through the first initial management, you can go on a very wrong path and no matter how good you are on the wrong path, you are gonna be wrong. So I think the key factor is to really realize what is the situation? What's the disease process? Create an accurate differential diagnosis and then have a nice plan for the initial management and I think after that, just proceed with the next steps. Do you have any thoughts? What is the most common step that people who fail would go wrong at?

- Well, I think that each of the grades has an opportunity for people to do well or fail. I think that the most important grade that we see is the management. The diagnosis tends to be an easier grade for people to get, it's the management. And so I'd really like to emphasize the importance of the management of the patient because much of the difficulty we have with the overall scoring system relates to the management grade.

- Okay and that's because if they go through the wrong management, really, it ends up in the wrong road, I assume. Isn't that correct?

- Right and then I also wanna emphasize that you've got complications here, but remember that the complication grade could be a perioperative complication, it could be an interoperative complication. And as I said, if there is no surgical management involved, it'll be scored on the natural history of that disease and understanding what to expect.

- Thank you, so these are some of the general questions. How many times can I take the test? Is it correct, three times now, without having to go back to the written exam Bill, would you clear that?

- Sure, it used to be twice, but this year we made it three times. So the candidate can take the examination three successive times before they're required to go back and pass the written test.

- Thank you and if somebody fails the first time, do you think that in any way affects the way they will be tested the second time?

- No and in fact, I think that's an important point is that the examiners have no knowledge when they're examining the candidates, whether they've taken the test before or not. And we make sure that the candidate, when they're being retested are not retested by the same directors.

- Thank you, this is a very open-ended question, how long to study for the boards? It depends really how comfortable you are if you're doing entirely cranial practice and you never do spine, you probably have to start earlier to study your spine. But what are your thoughts on this most common question? Should we stop a month, maybe hold our practice to a very light status and focus on reading more or less? What are your thoughts on that Bill please?

- So there's no hard and fast rules for this, obviously. In our junior faculty that I've counseled, and our residents that I advise that have gone on and taken the test, I do recommend them taking some time off their practices so that they can have focused study. I think the problem that I've seen people get into in the past is they're often in large multispecialty groups, possibly in an academic department or a big private practice group. They may be limiting their practice to some extent, to some certain subspecialty areas. And so clearly, they're not current with some of the management, say they haven't done pediatrics, or they haven't done complicated cranial surgery for some time. And you need to take the time to review this and go back and study. And I've never seen a candidate that's really taken the exam seriously, and they've understood this, fail the test because I think it's really a matter of just preparation. And remember that we're just trying to determine if they would be safe covering a broad spectrum practice. And so it will be necessary for a candidate who's in a busy practice to review the areas that they're not familiar with, or they're not doing a routine basis. So I would recommend them take perhaps a few weeks off their practice to really focus and study. And I would start reading several months or a year ahead of time.

- Thank you, and again, another open question, what to study? I've heard the Greenberg has really been very nice and I used it and I enjoyed it for the boards, I think other ones that are very available as well. Again, you have to mix and match, there's no single source, that's very comprehensive and it depends how much you feel comfortable. Do you have any pointers for that question, Bill?

- I think that's really an open-ended question, It really depends on the individual and what their background is. Clearly, I think that you need to have a good understanding of all these subspecialty areas. I think Greenburg gives a nice overview, not very in-depth in any area as you know, but a nice overview of the entire specialty. And I think that he wrote the book really designing in mind for the candidates to help prepare for their examination. I wanna make sure that everybody understands that we'll examine the pertinent physical exam aspects of peripheral nerve presentation, tumors and tract syndromes, et cetera. And that you may need to supplement Greenburg, in some of these areas that is not that comprehensive.

- Thank you. And you mentioned very well that what are the examiners looking for a safe neurosurgeon covering an ER practice, which has a capture of a general neurosurgical patients, anything else in detail they're looking for?

- No, and again, you have to think about that from a pediatric aspect as well, because we'll show you pediatric presentation. So you need to review and understand the fundamentals of all the pediatric neurosurgical practice.

- Thank you. How many cases per session to be comfortable, I have heard six cases is a good number, is that a correct number?

- We want to present at least six cases per session, and half of those questions that will be given will be standardized questions and they have good metrics on the scoring. And so we instruct the guest examiners and the directors to give at least six questions per session.

- Okay, so if somebody has five questions or four questions they've completed, does that mean to have a chance not to pass, but if they do well on the four or five, they will pass? I know this is a very difficult question to answer unless you know the candidate very well.

- We try not to let that happen, so we really try to get through six questions per session. It obviously depends on the particular candidate, some people are very easy to examine and go through the vignettes quickly, others are more difficult, but we're really instructed to do at least six questions per session. If there is less questions covered per session, it has no bearing on whether the candidate is going to pass or fail.

- Thank you, and how much details do you ask or do you require for people to pass the exam? Again, very open-ended, can you shed some light on this question?

- So I think what we're looking for is practical answers. So we're not looking for extensive differential diagnoses, including diagnoses that just aren't practical for that scenario. So we're asking for really practical answers to the questions. What are you going to do? We don't necessarily ask for a laundry list of potential options, we want to know what you're planning to do, and whether your management plan is safe for that particular patient. And we'll actually direct you in that group away because we need to move along the vignette. And I get through at least six questions, so we'll move and we may stop you in mid-sentence and move on if we have our answer.

- And I think this leads us to some of the pitfalls for the examinees is that sometimes because if they don't have the confidence in their answer, they try to list a number of diagnoses, a number of management strategies, just try to do a fishing expedition and make sure among all of these, somehow they come up with the right answer. I think that sort of not only takes more time, it leads the examiner to believe that they're not confident in their answer and usually leads in a bad outcome in terms of their scoring, don't you think?

- Yes, we want you to prioritize. And so we'll ask you the possibilities for a differential diagnosis, but we expect you to be able to prioritize. And then with respect to the management options, we want you to choose a minute an option and tell us in detail what you're going to do and justify the reasons for that.

- Thank you, and you can ask for radiologists at any time I was told, you don't have to necessarily interpret every image or endocrinologists, et cetera, but again, you have to be able to put a plan together based on that. So it is okay for me at any time to say I would like a radiologist to give me a differential diagnosis, is that an accurate question?

- That's correct, although we do expect people to interpret images appropriate to the management of the patient. Now we're not going to test them on radiological differential diagnosis to any extent, but we expect them to be able to make management decisions. And if you look at the definition of what a neurosurgeon does on the back of the board book, the definition includes interpretation of radiological images. And so I would suggest that the candidate not keep deferring to the radiologist opinion, we would expect people to make most differentials based on their own judgment of the images presented.

- Thank you.

- And back to the endocrinological evaluation, et cetera, if they have questions people can ask, and it's a interactive process of this examination at all times and they can ask for further information if they so wish.

- Thank you. So what are the pearls of success in general terms? Obviously you want somebody who is very confident, You don't want them to come across as somebody who feels he knows it all, he or she knows it all, and they're not gonna be listening to their colleagues to change a management plan on a patient. At the same time, you don't want them not to be sure about what they're doing and leave the patient sorta in a limbo in terms of what is the right management strategy. So if you say, what are the characteristic of a best examinee? What would you say in a few words? And at the same time, what are the pitfalls of those who fail?

- So the pearls of success, there's not any specific ones, but it's very clear when you're examining candidates, their level of knowledge. And because we can escalate the difficulty of the questions at any part of the examination to determine the level of knowledge of that particular candidate. I think the successful candidates are those ones who have taken the exam seriously, they've prepared for the exam, they've reviewed all aspects of neurosurgery and neurology and it's very easy to tell if people have done all the requisite work to bring their level of knowledge up to that. And we can, again, determine very quickly what the level of knowledge is in each of these areas. The pitfalls of those who fail I see, there was a number of candidates over the recent past that we've had who've been superior in one area and they clearly had not prepared in other areas. And that left them with big gaps in their knowledge, and that was the reason that we instituted the scoring system whereby there's a minimum passing grade for each of the subspecialty areas, because we had found many candidates who had performed so well in one area that the comprehensive score would have passed them, but they clearly had gaps in safety in some of these other areas. So I think those are the pitfalls that we see most frequently of people who haven't prepared at certain aspect areas that they're not familiar with.

- Thank you. So as you very well mentioned too much subspecialty focus can be a big problem. If you have a purely cranial practice and you say I'm gonna do well on cranial, and makeup for it in spine, well, that's not a good strategy. This board certification is for all of neurosurgery, you're board certified neurosurgery, you are not board certified in cranial surgery only, or spine surgery. So the exam reflects such a requirement. How to approach this problem, I think the best way is just spend more time if you're doing a purely cranium practice to study more on spine. And I think that's pretty much the number one reason why people fail is because their practice is so super specialized that they don't really try to manage problems that is out of their subspecialty, and therefore, when they're encountering these questions on exam day they feel very uncomfortable, am I correct?

- Yes, and I think that just emphasizes the points that I was making, that you need to really study neurosurgery as a comprehensive specialty and make sure that your knowledge basis is up in all of these areas.

- Thank you. And is there a difference in grading of people who do purely spine and they haven't really done a cranial practice for the past five years?

- So that's a good question, Aaron. And I think we understand that people have very focused practices. In fact, the majority of people we see in academic practice for instance, are very focused practices. So we understand that they may be exemplary in certain areas, but the way the exam is given and scored, it's understood that we score everybody the same on all the questions, whether it's within their subspecialty area or outside of their area. And we have a review and we know the scope of their practice when we examine them, but they're all scored the same.

- Okay, the second pitfall in my mind has been time management. You gotta have a very good handle on your timing, if they give you a sheet of paper, I usually, every time I finish a question I put in one, then put two, then put three for third question, and I watch the sort of my time on the clock every 15 minutes, I see what question I'm on and how much time has passed by. If I feel like I have been sort of going slow and 30 minutes has passed by, and I'm only on the second question, that means you gotta hurry up. It doesn't matter what's going on in my opinion, you gotta shorten your answers in some way, you've gotta become more succinct and you gotta move along. I think the examiners are gonna help you but they only can help you to some degree. They're not gonna tell you, well, stop talking right now, let's go to the next question all the time. If they feel like you're really taking your time and you're not sure you're gonna be your worst enemy. Do you have any thoughts on that?

- I think that the time management, it should be more in the realm of the examiner at this point, because we really want to examine at least six vignettes per session, so we'll move along. And the other point that I'd like to emphasize to the candidates is that the examiner may stop without question and move on to the next question. So if an examinee is stumped in something, we just move on, because it's to the examinee's benefit if we can examine more questions in that scenario, so that that one question is weighted less in the overall exam. And so if they stump, we'll move on, if they've done very well, we may move on early as well. So the time management should be left more in the realm of the director running the exam.

- Right, obviously you don't wanna be nervous, everybody is nervous on that day. And you come to the hotel in Houston, you go to the 12th floor, I believe, there's a very small room, I never forget how small that room was. You get 15 folks, all in a black tie and a black suit, I'm sorry, in a black suit and a tie, all standing, not talking to anyone else. Mary Lewis, who does such a spectacular job, walks into the room and you suddenly hear, there's just people oozing stress through their faces and after that, I think she tells you the schedule of who is examined by who, and there are different rooms in the hotel and obviously the beds are removed and there's a very professional environment and you end up going from room to room every hour. And between every hour there is a little bit of break, and again, describing these just for our examiners, I'm sorry, examinees to understand more about what happens that day. And really the key part of it is obviously be on time, get there half an hour early, could be traffic in Houston in the morning at that time. And I think you should take this as a very reasonable experience on behalf of the examiners. I don't think they have ever been unfair, at least in my experience and the people I have talked to, the questions has been very fair, the discussions have been very reasonable, they have in no way trying to trick anyone and it's really, at least in my mind, has been experience both learning and both knowing what is it that... Well, we should, as neurosurgeons focus on in the eyes of our seniors. Any thoughts in that area, Bill, please?

- Yeah, I mean, I don't really have much to add to that. I will tell you that the deliberation of the Oral Exam Committee is that we try to make the examination as fair as possible. And I think that all of the guests examiners that examine with us twice a year, I think are very struck by the amount of time and energy we spend trying to make the exam as fair as possible. And I think the benefit of the doubt always goes to the candidate, if there's a discrepancy in process or scoring. And we're constantly, it's an inner process and we're always trying to improve the exam and make sure that we're being as fair as we can be.

- Thank you, and I guess you've gotta approach every question systematically, and I think one of the problem is not leaving the examiner with a sense of confidence in yourself that you are safe as a surgeon, I think those are pitfalls. The key three things be safe most importantly, be humble and be confident at the same time. Let's go ahead and review some cases. I think that will be important to illustrate some of the details.

- Okay, so we thought we would present it as sort of a typical presentation of a case for your review. And what we have here is a 72 year old woman with a 15 plus year history of progressive changes in facial appearance. Her past medical history includes a insulin dependent diabetes for 30 years, hypertension, kidney disease, breast cancer, and skin cancer. She's had a mastectomy in the past, an appendectomy, a cholecystectomy, nephrectomy, hysterectomy, knee surgery, and cataracts. Her current medications include aspirin, Glucophage, insulin, Norvasc for hypertension, K-Ciel, benazepril, magnesium, glucosamine, and Trazadone. And this is her facial appearance, and I've got another picture here from the side and also your hand next to her hand.

- And what do you-

- So this-

- Yes, go ahead, Bill.

- At this point, we would ask you to present a differential diagnosis.

- And what would you expect them to include in the differential diagnosis, Bill?

- Well, as you can see from this case, she's got course features consistent with acromegaly and there's very little else on the differential diagnosis. Now in support of the diagnosis of acromegaly she's insulin dependent diabetic, and she's had multiple other tumors in the past, and she's got all the facial features of acromegaly, including enlargement of the nose and coursing of the features and enlargement of her hands and feet. And so a very limited differential diagnosis here, it should be a very straightforward diagnosis for most candidates. If they stumble, we would give them help, we would tell that her hands have enlarged and her feet enlarged and her shoe size's changed, et cetera. But we would expect them to come up with basically a diagnosis of acromegaly, there's very little else on the differential.

- Correct.

- Now the good candidate then would be able to plan a management strategy, which would include a radiographic and an endocrinological workup for acromegaly. So the MRI demonstrates a large macroadenoma here with possible cavernous sinus invasion, and the gland push over to the far right, and this is the adenoma. And then the appropriate endocrinological workup would include obviously a growth hormone IGF-1, which were both elevated in this case, cortisol, prolactin and the thyroid function tests were normal. Now we would expect them to discuss the general management of the acromegalic patient, which would include a workup for correlated medical problems. The patient, as we know, already has diabetes, but we would want them to know whether there was a cardiac, any abnormalities, such as acromegalic associated cardiomyopathy. We would want them to understand that they need to be worked up for colon polyps. And so then you'd do colonoscopy, and then the management of the tumor, which in this case would be surgery, possibly in addition to medical therapy as well, or radiation therapy, if a surgery wasn't effective. So we would then ask them to plan a management strategy. In this particular case, we would hope that they would include surgery in the differential or in the management and then what they would do and how they would perform the normal operation, this case to remove the tumor. And then how they would address the potential cavernous invasion, I can't tell from that particular scan whether for sure or not there's cavernous sinus invasion. But if there were cavernous sinus invasion, what they would plan to do with the remaining tumor and whether they would treat with adjuvant medical therapy and or radiation therapy and what the algorithm of treatment would be in this particular case.

- And I assume that you would record that they know about how to position patient on the table, how to do a transfer and all operation in details in terms of, obviously you don't expect them to know sublabial and endonasal, at least one of those, they should be comfortable on how to do a septal dissection removal of the sphenoid bone and interface of sphenoid bone opening the sellae and removing the tumor. Maybe potentially describe a situation where there was a CSF leak intraoperatively or potential carotid artery injury and see how they would manage this. Is that correct?

- Yes, so in the examination room, we have a mannequin for people so that they can draw their approach. We have a skull and then we'll discuss specifically aspects of the surgical procedure. We'll ask them how to position the patient, we'll ask them how they'll plan their flap, and if they were doing a transcranial approach or in this case, a transsphenoidal approach, how they would do that, specific aspects along the way, whether they would do a sublabial versus an endonasal, whether they would use an endoscope and then how they would approach the sellae, and what the goal of surgery would be, how aggressive they would be with removing the tumor, what they would do with the cavernous sinus component, how they would close, how would they would avoid a CSF leak in this particular case with the closure? And then anywhere along the line, we could give them an example of an intraoperative complication or a postoperative complication. So the intraoperative complication, as you mentioned, could be a CSF leak or a carotid artery injury and how they would manage that. Or a postoperative management problem may be nearly handling diabetes insipidus after a pituitary surgery or a rebound hyponatremia a few days later.

- And you would expect them to know the dose of the AVP, I assume, is that correct?

- Yes, we would expect them to know most of the generalities of treatment. We may not expect them to know the specific dose of certain medications, but how it would be managed, and we would expect them to be able to understand the concepts of management, not just defer to subspecialty or consultation expertise to help them. So we would expect them to be able to manage electrolyte problems after pituitary surgery, both diabetes insipidus, as well as SIDH down the line.

- And just to clear for our viewers, if there's a carotid injury, obviously you wanna pack the wound, get control of the bleeding, and then at this time, stop, don't do anything, remove the retractors, keep the patient intubated, go to the Angio Suite and rule out an evidence of pseudoaneurysm, which could be treated intervascularly. It would not be appropriate to just pack and continue doing more work as you're losing more blood and placing the patient at risk. If you have a CSF leak intraoperatively, you wanna pack it with fat and bone to reconstruct the floor and potentially consider a lumbar drain, if there is evidence of a large tear in the diaphragma sellae. Postoperatively, if there is a delayed CSF leak, you would like to manage with a lumbar drain for five days and then remove and stop the drain, see if that would heal the leak, otherwise consider reexploration surgery. Any details in that regard, Bill?

- No, I think that you've covered most of it there. And again, remember that the management includes preoperative management, so in this case for dogging, the fact that they could have colon polyps, possibly colon cancer, cardiomyopathy, hypertension, diabetes, and then perioperative complications and postoperative complications, including electrolyte problems or delayed CSF leak, for instance. So all of that is included in the management grade and then managing the complications.

- Thank you, Bill. So let's go ahead and review a few cases of mine as well. A 60 year-old female with one year history of a right upper extremity weakness and shoulder pain. She does complain of right shoulder weakness on exam, there's definitely a 4/5 weakness as well as right hand weakness. She's was actually a dancing teacher, and evidence on myelopathy and increased reflexes in bilateral lower extremities. I'm sorry, Bill, I'll go ahead and go back to my slide. And slight gait ataxia. And I think at this point it's reasonable for the examiner to ask where would you position the lesion in the neuro axis? And as you can see, the patient has evidence of myelopathy and also evidence of right shoulder weakness. So one may say, well, evidence of shoulder weakness where cranial nerve 11 is and evidence of spinal cord compression could potentially explain all of these. So a lesion at the level foramen magnum would be a reasonable answer. Isn't that correct?

- Yeah, I think after C spine foramen magnum would be a very reasonable area for this.

- Thank you, and as you can see, an MRI was completed that shows a lesion at the foramen magnum, and I assume the examiner would ask for differential diagnosis. There is very few things that look like this, this is obviously a meningioma, Bill. Would you have a problem if I say this is a meningioma? And I think the list of the things are very low, my differential, therefore, I feel confident and just move on and don't give any more differential diagnoses?

- Yeah, I think the only thing that I would say in this particular case is we all appreciate this, is most likely a meningioma. And when you hear hoofbeats you think of horses and not zebras. There's one or two other things that you need to think about, one would be a dural met from breast in a woman. And I think that can be an always being a meningioma mimic. And then other thing of course, meningiopericytoma. But most likely the first five on the differential would be a meningioma, I absolutely agree with you.

- Thank you. so after that, the examiner I'm sure is gonna ask, so how would you manage this? Obviously surgery, this patient is symptomatic from evidence of compression and they will ask how you would position the patient? How would you approach it? This is how I have approached this, again, there's many ways to skin a cat, this is not about answering the questions the way I do it, it's about what's safe for the patient. And in this way, we put the patient lateral, we use monitoring and obviously, when you answer your questions think about all aspects. If you don't mention monitoring and you go ahead and answer everything, and later, you get disappointed because you didn't get all the points for exam, say, why did I miss? They say, well, you didn't mention that you're gonna use monitoring. I said, well, I would have used it, I just forgot to say it, that's what won't work. The examiners wanna hear exactly step-by-step, how do you position, putting the patient on MAYFIELD Clamp, obviously we all do that, but briefly going over the monitoring, would you put a lumbar, a drain? I don't think that's necessary. How would you place the head of the patient in a clamp that we make sure you the head of the model and show you how to position it and what kind of incision you would use? In this case, we use this sort of a small hockey stick incision, and where would be your craniotomy? And take it from there. Any other details, Bill?

- No, I think that that covers it. I think monitoring would be very helpful in this case, 'cause you'd be concerned about even positioning the patient, making sure that there's no compromise with that. And the type of incision, the approach that you're going to use. And again, as you mentioned, there are many different ways to manage several of these patients that we'll discuss, but we wanna make sure that it's safe and it's reasonable. And if you can justify that, that is fine.

- Thank you, and this patient actually had her tumor removed and she did very well. Actually, I really enjoyed this case, skull base meningioma was fun. But iterate that to get to the point, she came back about 10 days later and we removed her sutures, she had a little bit of swelling in the back of her neck, and now she comes back about a month later and she has this very large swelling in the back. And I guess at this point, the examiner would like to know, well, what do you think is going on? And what other tests would you like to order? I would expect the examinees to say, well, I don't see any obvious evidence of infection, most likely would be a pseudomeningocele, I would like to do a head CT to rule out hydrocephalus. Any thoughts on that, Bill?

- Yeah, no, I think that's appropriate. Obviously the differential would be pseudomeningocele versus infection and you should be able to easily tell those two apart, both by clinical signs and also with some laboratory studies such as a white count or a CRP or a sed rate. And then a imaging study to see if there's evidence of infection at the operative site or whether this is a most likely just CSF.

- Sure, and this was the CT that was performed, again, showing the pseudomeningocele in the back of the head and there's no obvious evidence of hydrocephalus. So at this time the pseudomeningocele is relatively soft and I would expect the examinee to say that, well, I don't think there is a necessity for the shunt because with times many of the pseudomeningocele will resolve on their own. And at that point I would say the patient was doing well, no other issues, but comes back, and the pseudomeningocele is very tense and it's placing the incision at risk. And you repeat a CT scan, it looks about the same, at that juncture, I would like them to consider some sort of CSF diversion, such as a shunt. Would you manage it differently?

- Yeah, I think that, again, this is one of these issues, there may be different approaches to this, but we'd want the candidates to consider a procedure such as a lumbar drain, perhaps as the next step, revising the wound and then ultimately, may require a shunt if there is evidence of hydrocephalus, underlying this. At this point in time, when she initially presents, I'm unsure as to whether this represents a closure issue versus hydrocephalus. And I would give the patient the benefit of the doubt and try to avoid a shunt and deal with the lumbar drain, perhaps revising the wound before I commit her to a shunt. But that's my personal management algorithm.

- That's fair, and I think that's very safe and very fair. I would have said we thought we closed the dura very tight in surgery and we didn't think we can do any better when we go back. And I think having a possible further exploration is very reasonable, I think a lumbar drain is reasonable and potentially considering a shunt. In this case, we felt we had closed the dura very tight, and my personal experience has been that the lumbar drains haven't helped, so we went ahead and shunted her and she did very well. But again, it's just thought process, there's no right answer, especially for cases such as this, it's more that the thought process is safe and the examinee is not necessarily sorta not intervening when the incision is breaking down, which would increase further complications in the future. A 49 year-old man with progressive history of visual dysfunction for the past five years and evidence of uncinate fits with characterized peculiar smells. And we would like them to have an idea of where the lesion would be, visual dysfunction, something involving the optic apparatus, as well as the medial temporal lobe. So a lesion that will be located sort of around the opticocarotid cistern would be very reasonable. And at that point, an imaging is reasonable and he will do the MRI showing this mass. And I assume you would be asking them for a differential diagnosis at this time. And it could be a meningioma, it could be any other tumors such as a craniopharyngioma, and pituitary macroadenoma. And here is the images on T2, if you need more images and then what would be your management strategy in this case? I assume a neuro-ophthalmological evaluation is reasonable. What are your other requirements for answering this question, Bill?

- Well, we would expect them to look at the pattern of growth of the tumor. And obviously the patient has some visual problems and some seizures, we would expect them to pay attention to the hypothalamic pituitary axis in a case like this. The sellae is enlarged, the sphenoid actually is got tumor and it looks like.... And the cavernous carotid on the right side is completely encased with tumor. So we would hopefully have them consider a tumor such as a meningioma, large invasive meningioma, a pituitary macroadenoma, I think are the two top tumors on the differential. And we would expect them to consider an endocrinological workup, to consider as some types of pituitary tumor, also functional pituitary tumor, which is an important one to rule out in this case, because it will change the management.

- Thank you, and then an endocrinological evaluation was positive for prolactin 4,500. And this was a prolactinoma, it is very much off a midline and the wrong answer, which would really put you in a very bad road would be consider resection. And you would get in there, this tumor would be very adherent, would place the patient at risk. So one of the big deals, I think that we need to make sure examinees understand is we don't want operation for medically treatable situations. That's including taking out an MS plaque, treating a prolactinoma through surgery because the differential diagnosis was not broad enough. And I assume it is appropriate to know the treatment, examiners would like you to know some of the dosing aspects for Parlodel or bromocriptine and side effects, and what are the second line therapies, if the patient has side effects in terms of Dostinex and what's the dosing for that, and what are the side effects and how to manage the patient and how to follow the patient after the a medication is incorporated? So the examinees should have a high index of suspicion for medically amenable conditions, which mimic neurosurgical disorders. And that includes Guillain-Barre syndrome or other neurological disorders. Let's go ahead and maybe finish with one or two more cases. 54 year-old male with left sided facial twitches and probably the examinee should ask, well, how did they start? What features they have? And then they start around the eye, later involved the pre-oral area. And we would like to lead them to the diagnosis of potentially hemifacial spasm and would say, well, they have been treated with Botox as first line of therapy and they really don't like the cosmetic deformity, they really would like to proceed with a more definitive therapy. And at that juncture, we would like them to know that an MRI should be performed before considering treatment of cranial compression syndromes. Don't you agree with that, Bill?

- Yes, exactly, we would hope that they would be able to give us a description of the general medical management of the patient prior to considering surgery in a case with hemifacial spasm. But we would expect them to also plan to have a scan on the patient and make sure there's no underlying pathology underlying the hemifacial spasm.

- Thank you and here's the MRI showing extra large lesion going transtentorially involving the medial temporal lobe and upper cranial nerves. And at this juncture, we would show them an MRI, and we would like to differential diagnosis, I guess it's fair to tell them, well, I would ask my radiologists what's differential diagnosis and the diffusion images would give it away. As you can see here in the left medial temporal lobe, hyperintense images on diffusion, sequences is characteristic of an epidermoid tumor. Is that fair, Bill?

- Yes, we would expect them to be able to come up with a very reasonable differential for this, but really hone in on the diagnosis about the dermoid given its diffusion characteristics.

- Thank you, and then this is postop how it was approached through a two-stage, I think how you position a postoperation first and then removal more superiorly, and just the details related to complications in terms of aseptic meningitis and how you would manage that postoperatively, I think is critical in management of epidermal tumors. So a 75 year-old male with a transient left upper extremity weakness. He was evaluated in an outside hospital with an MRI and a CT scan. And we would like them to give an idea of what they see, it looks like a hemorrhagic lesion in the medial right postparietal area. This patient was subsequently discharged, continued to improve and had another episode and was not happy with the care at the initial hospital and therefore shows up in your hospital, and would like to know what's going on. There was no triggers for this hemorrhage and at this juncture, we would like them to potentially consider a vascular study for a spontaneous intracranial hemorrhage. Don't you agree, Bill?

- Yes, absolutely, a good vascular study was there a contrast study done with the MRI?

- The contrast study was done and I will see if I have it to show it to you, but it did show evidence of hemorrhage and nothing else.

- Yeah, so we would proceed with a vascular study here, probably a CTA is our initial study, perhaps an angiogram.

- Okay, and here is that internal, I'm sorry, a carotid angiogram, really showing nothing positive. And then next step you can see a more venous phase, there is no abnormality. And I assume you would like to ask him what to do next, isn't that correct, Bill.

- Sure, if we went to a formal angiogram, we would ask them what they would do next. I think the obvious thing here is that the external carotid needs to be imaged to make sure that there's no fistulas component coming from the external carotid circulation, i.e. a dural fistula.

- Thank you, and that's it, I think it is reasonable if you show them a set of images and it doesn't show anything, they can ask for the other sequences for lesions that are often missed, especially parasagittal dural fistulas. And as you can see an external injection reveals enlarged dural fistula, and you would expect them to consider endovascular versus surgical options for disconnection of the fistula and what they find interoperatively in this case, endovascular option was not reasonable after discussion with the colleagues and how to perform a parasagittal craniotomy, identify the feeders to the sinus and be able to identify those abnormal fistulas connections and disconnect them considering intraoperative angiogram to assure disconnection and postoperatively, obviously, if there's any evidence of infection or a CSF leakage, how would it be managed? Would you ask any other questions, Bill?

- No, I think that you've covered most of it. We would expect them to give us a description of the general management of dural fistulas, and the options for management of this particular one. And if they do it from an endovascular side, how they would do that and what the object would be. And then if it's deemed that endovascular treatment was not possible or appropriate, then how to achieve a surgery.

- Okay, thank you. Bill, I wanna thank you for your time and we appreciate all your comments, I think this was very helpful for all of us.

- A pleasure to be involved and thank you very much, Aaron, great job.

- Thank you, Bill, thank you as always.

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