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The interesting paper by Li et al. reports an important series of
cases treated appropriately and carefully followed-up, but unfortunately
the diagnosis may not be correct in all cases.
Fusiform aneurysms appearing in angiograms may represent a variety of
different histopathological pictures, including dissection, but also other
types of aneurysms.
A light to this question, quite recurrent in my p...
The interesting paper by Li et al. reports an important series of
cases treated appropriately and carefully followed-up, but unfortunately
the diagnosis may not be correct in all cases.
Fusiform aneurysms appearing in angiograms may represent a variety of
different histopathological pictures, including dissection, but also other
types of aneurysms.
A light to this question, quite recurrent in my practice, is bring by
Mizutani et al.(1). They studied 85 patients with fusiform or non-
branching zones aneurysms, either operated or post-mortem. Four types of
aneurysms were found, one of witch is what the literature came to call a
"blood-blister- like aneurysms", and is not fusiform. The fusiform
aneurysms were found to have 3 different patterns. One of them is a
segmental ectasia with regular walls and a benign course. Two other types
are symptomatic and may share some features that bring confusion. First,
the classic dissecting aneurysm has typically an acute presentation with
ischemic or hemorrhagic stroke. Angiography shows fusiform dilatation with
irregular wall and associated with stenosis. Pathology was characterized
by disruption of internal elastic lamina, a false lumen packed with fresh
thrombus, no intimal thicketening and no organized thrombus. The second
is the dolichoectatic aneurysm, clinically characterized by compressive
symptoms or brainstem ischemic changes, with a chronic evolution, that may
bleed, but rarely in previously asymptomatic cases. The angiography shows
marked tortuosity and very irregular walls. The most common localization
is basilar artery. Pathology shows organized luminal thrombus, disrupted
internal elastic lamina without false lumen. As a chronic condition with
organized thrombus, parietal calcification can occur.
In the series, at least four patients had no acute presentation, and there
was no hemorrhagic stroke.
The images presented for cases 3, 4 and 8, although they had sudden
presentation, are characterized by tortuosity, ectasia and irregular
walls, extension to vertebral arteries and no stenosis. In one case the CT
images show wall calcifications. These images are more consistent with
dolichoetatic fusiform than with acute dissecting aneurysms.
More rigid criteria are needed to define dissecting aneurysms and
differentiate them from dolichoectatic aneurysms.
1- Mizutani T, Miki Y, Kojima H, Suzuki H. Proposed classification of
nonatherosclerotic cerebral fusiform and dissecting aneurysms.
Neurosurgery. 1999 Aug;45(2):253-9.
We read with interest the recent editorial by Fiorella et al.,
entitled "Should Neurointerventional fellowship training be suspended
indefinitely?", detailing the potential hazards of neurointerventional
(NI) overtraining in the United States (US).1 We face similar issues in
Australia pertaining to our own current NI workforce demand and NI trainee
employment outlook.
We read with interest the recent editorial by Fiorella et al.,
entitled "Should Neurointerventional fellowship training be suspended
indefinitely?", detailing the potential hazards of neurointerventional
(NI) overtraining in the United States (US).1 We face similar issues in
Australia pertaining to our own current NI workforce demand and NI trainee
employment outlook.
The landmass of Australia is twice the size of the European Union and
almost as large as continental US (excluding Alaska and Hawaii).2 However
the vast majority (>85%) of the 23 million population live within 30
miles of the coastline, and 98% live in major cities or regional areas
where access to NI services are considered to be available.3
Currently, 30 practising neurointerventionalists service this
population. Similar to the USA, most perform additional non-NI work such
as diagnostic radiology, medical neurology, or open surgery. Given the
core NI skillset of intracranial aneurysm and intra-arterial stroke
treatment, we focused our analysis on these specific services.
Local vendor survey estimates reveal that approximately 1300
aneurysms are treated by endovascular techniques per annum in Australia.
This has remained relatively stable over the last 3 years. This yields
just over 40 aneurysms per practitioner per year, or almost 1 case every
week.
Approximately 50, 000 people suffered a new or recurrent stroke in
2012 in Australia.4 Approximately 80% were ischemic strokes, and if all
patients had presented to comprehensive stroke centers, optimistically 3%
could have received intra-arterial therapy. 5 Extrapolating from this
data, this could yield a theoretical 1200 cases per year, or under 1 case
per practitioner per week. However, the recent simultaneous publication of
three randomized clinical trials that failed to demonstrate benefit for
intra-arterial therapy in acute ischemic stroke patients will undoubtedly
slow this potential growth.6-9 Even if this potential growth came to part
fruition, the fact that the current practicing neurointerventionalists in
some centers spend up to 50% of their work hours performing non-NI work,
means this demand could be easily met by the current pool of practitioners
increasing their NI work load.
Despite this relatively low average case volume per operator, we
continue to train additional NI fellows. Currently, 15 Australians are in
various stages of NI training either in Australia or overseas. Thus our NI
workforce is predicted to expand by up to 50% within four years.
The oversupply of US NI trainees may be potentially leading to the
expansion of NI services at community hospitals, and to the shift of
cerebral aneurysm treatment from high-volume to low-volume centers.10 This
is a concerning trend for patient safety, as higher volume centers are
known to have better outcomes. In Australia, NI services are largely
provided by public health services that have significant budgetary
constraints. Given the costs associated with an active NI program, there
are pressures to contain rather than expand NI services, which are already
fully or nearly fully staffed. This situation will persist until there are
solid data provided to justify service expansion. For the primary author
who is a current NI trainee, this translates into a bleak NI job market.
Many NI trainees will likely find that there is no NI position available
to them after a protracted and intense course of NI training.
The low case volume and concerns for quality of patient care also
highlight the need to have credentialing for both fellowship programs and
existing practitioners to ensure future NI trainees receive an adequate
breadth of experience, and existing practitioners maintain safe and
quality practice. The Royal Australian and New Zealand Society for
Neuroradiology is already in the process of introducing a system of
registration and credentialing of NI training programs and defining
guidelines for ongoing credentialing of current and future practitioners.
This may assist in regulating the imbalance that appears to currently
exist.
We commend Dr. Fiorella and his colleagues for highlighting this
important issue. As a global NI community, we have a responsibility to
provide prospective NI trainees with a pragmatic view of the current and
future NI workforce while protecting the quality of care for our patients.
The current Australian reality is that there are too many NI trainees, and
too few NI jobs.
1. Fiorella D, Hirsch JA, Woo HH, Rasmussen PA, Shazam Hussain M, Hui
FK, et al. Should neurointerventional fellowship training be suspended
indefinitely? Journal of neurointerventional surgery. 2012;4:315-318
2. Australian bureau of statistics: 1301.0 - year book australia, 2009-10.
http://www.abs.gov.au/AUSSTATS/abs@.nsf/0/047D4BA4016F7A0BCA25773700169C25?opendocument.
Accessed 25 Dec 2013. Last updated 4 Jun 2010.
3. Australian bureau of statistics: 3218.0 - regional population growth,
australia, 2012.
http://www.abs.gov.au/ausstats/abs@.nsf/Products/3218.0~2012~Main+Features~Main+Features?OpenDocument#PARALINK3.
Accessed 25 Dec 2013. Last updated 30 Aug 2013.
4. Stroke foundation.2013
5. Cloft HJ, Rabinstein A, Lanzino G, Kallmes DF. Intra-arterial stroke
therapy: An assessment of demand and available work force. AJNR. American
journal of neuroradiology. 2009;30:453-458
6. Mocco J, O'Kelly C, Arthur A, Meyers PM, Hirsch JA, Woo HH, et al.
Randomized clinical trials: The double edged sword. Journal of
neurointerventional surgery. 2013;5:387-390
7. Broderick JP, Palesch YY, Demchuk AM, Yeatts SD, Khatri P, Hill MD, et
al. Endovascular therapy after intravenous t-pa versus t-pa alone for
stroke. The New England journal of medicine. 2013;368:893-903
8. Kidwell CS, Jahan R, Gornbein J, Alger JR, Nenov V, Ajani Z, et al. A
trial of imaging selection and endovascular treatment for ischemic stroke.
The New England journal of medicine. 2013;368:914-923
9. Ciccone A, Valvassori L, Nichelatti M, Sgoifo A, Ponzio M, Sterzi R, et
al. Endovascular treatment for acute ischemic stroke. The New England
journal of medicine. 2013;368:904-913
10. Brinjikji W, Lanzino G, Kallmes DF, Cloft HJ. Cerebral aneurysm
treatment is beginning to shift to low volume centers. Journal of
neurointerventional surgery. 2013
We read with interest Dr. Ding's response to our manuscript,
"Angioarchitectural features associated with hemorrhagic presentation in
pediatric cerebral arteriovenous malformations," and we thank him for his
gracious comments. In response to his question regarding whether brain AVM
angioarchitecture influences our particular treatment strategy, we would
point out that the overwhelming majority of our pediatric patients wi...
We read with interest Dr. Ding's response to our manuscript,
"Angioarchitectural features associated with hemorrhagic presentation in
pediatric cerebral arteriovenous malformations," and we thank him for his
gracious comments. In response to his question regarding whether brain AVM
angioarchitecture influences our particular treatment strategy, we would
point out that the overwhelming majority of our pediatric patients with
brain AVM present with hemorrhage or with an AVM-related neurological
symptom. Thus, we are rarely in the position of evaluating an entirely
asymptomatic AVM, in which case particular features of the
angioarchitecture might weigh heavily in assessing whether to proceed. Our
treatment strategy, once the decision has been made to proceed, is
designed to as definitively as possible ensure complete removal of the
AVM, wherever feasible. We thus favor surgical resection, with
preoperative embolization used where this would lower morbidity and
improve surgical outcome. Given the age of our patients, we tend to favor
radiotherapy less than would typically be the case in an adult cohort. We
hope to describe the details of our multidisciplinary approach to
treatment in a future publication.
I have read, with great interest, the paper by Ellis et al. titled
'Angioarchitectural features associated with hemorrhagic presentation in
pediatric cerebral arteriovenous malformations [1]. The authors
retrospectively reviewed the angiographic features of 135 pediatric
patients, mean age 10.1 years (range 0-19 years), who were referred to
Hospital for Sick Children in Toronto, Canada and Boston Children's
Hospital ove...
I have read, with great interest, the paper by Ellis et al. titled
'Angioarchitectural features associated with hemorrhagic presentation in
pediatric cerebral arteriovenous malformations [1]. The authors
retrospectively reviewed the angiographic features of 135 pediatric
patients, mean age 10.1 years (range 0-19 years), who were referred to
Hospital for Sick Children in Toronto, Canada and Boston Children's
Hospital over a period of 11 years from 2000 to 2011. The most common
presenting symptoms were hemorrhage (64%), seizure (13%), and focal
neurological deficits or headache (13%). The authors sought to identify
angiographic features associated with AVM rupture at presentation.
Multivariate logistic regression analysis identified smaller size
(P<0.01), exclusive deep venous drainage (P=0.02), and infratentorial
location (P=0.01) to be independent predictors of hemorrhagic
presentation.
Given the relatively little information available regarding the
natural history of pediatric compared to adult AVMs, this study represents
an important contribution to the pediatric AVM literature. As the authors
note, there is an increased tendency to aggressively treat AVMs,
especially ruptured ones, presenting in children compared to those in
adults due to the higher exposure to hemorrhage risk and hemorrhage-
related morbidity and mortality by children. Given what is currently known
regarding the natural history of AVMs, which is largely derived from adult
patients, this rationale is seems valid [2]. A Randomized Trial of
Unruptured Brain AVMs (ARUBA) is a study of adult patients only [3]. It is
unknown whether the results of ARUBA, which are pending imminent
publication, will alter the management of unruptured pediatric AVMs.
It would be very interesting to know how the patients described in
this study were treated and whether hemorrhagic presentation and AVM
angioarchitectural features influenced the treatment strategies. Although
the method by which AVM obliteration is achieved is biased, at times
significantly, by the treating physician and institution, no single
modality, including endovascular embolization, microsurgical resection,
and radiosurgery, has emerged superior to its counterparts. For example,
AVMs with smaller size and exclusive deep venous drainage, which typically
implies deep location, are ideal radiosurgery targets [4-5]. However, in
the setting of AVM rupture, some may advocate for microsurgical resection
in order to rapidly eliminate future hemorrhage risk. Additionally, the
authors did not distinguish infratentorial location by brainstem versus
cerebellum. Recently, the UCSF cerebrovascular group described cerebellar
AVMs as anatomically distinct lesions from cerebral AVMs with a higher
propensity for hemorrhagic presentation [6]. Not surprisingly, cerebellar
AVMs are significantly more conducive than brainstem AVMs to surgical
resection therefore underscoring the importance of distinguishing the two
locations.
In summary, the authors should be congratulated for identifying
independent predictors of hemorrhagic presentation in a relatively large
cohort of pediatric AVMs combined from two tertiary pediatric referral
centers of international repute. Given the difficulty of obtaining
prospective data regarding the natural history of pediatric AVMs, the
cerebrovascular community will continue to rely on this study and others
like it to guide decision-making for the management of these rare and
complex vascular lesions.
References
1. Ellis, M.J., D. Armstrong, S. Vachhrajani, A.V. Kulkarni, P.B.
Dirks, J.M. Drake, E.R. Smith, R.M. Scott, and D.B. Orbach,
Angioarchitectural features associated with hemorrhagic presentation in
pediatric cerebral arteriovenous malformations. J Neurointerv Surg, 2013.
5(3): p. 191-5.
2. Gross, B.A. and R. Du, Natural history of cerebral arteriovenous
malformations: a meta-analysis. J Neurosurg, 2013. 118(2): p. 437-43.
3. Mohr, J.P., A.J. Moskowitz, C. Stapf, A. Hartmann, K. Lord, S.M.
Marshall, H. Mast, E. Moquete, C.S. Moy, M. Parides, J. Pile-Spellman, R.
Al-Shahi Salman, A. Weinberg, W.L. Young, A. Estevez, I. Kureshi, and J.L.
Brisman, The ARUBA trial: current status, future hopes. Stroke, 2010.
41(8): p. e537-40.
4. Kano, H., D. Kondziolka, J.C. Flickinger, H.C. Yang, T.J. Flannery,
N.R. Awan, A. Niranjan, J. Novotny, and L.D. Lunsford, Stereotactic
radiosurgery for arteriovenous malformations, part 2: management of
pediatric patients. J Neurosurg Pediatr, 2012. 9(1): p. 1-10.
5. Yen, C.P., S.J. Monteith, J.H. Nguyen, J. Rainey, D.J. Schlesinger, and
J.P. Sheehan, Gamma Knife surgery for arteriovenous malformations in
children. J Neurosurg Pediatr, 2010. 6(5): p. 426-34.
6. Rodriguez-Hernandez, A., H. Kim, T. Pourmohamad, W.L. Young, and M.T.
Lawton, Cerebellar arteriovenous malformations: anatomic subtypes,
surgical results, and increased predictive accuracy of the supplementary
grading system. Neurosurgery, 2012. 71(6): p. 1111-24.
I have read, with great interest, the paper by Stemer et al. titled
'Acute embolization of ruptured brain arteriovenous malformations' [1].
The authors describe a cohort of 21 patients with ruptured intracranial
arteriovenous malformations (AVM) who were treated with endovascular Onyx
(ev3, Irvine, California, USA) embolization in the acute phase following
hemorrhage. The median interval from hemorrhagic presentation to...
I have read, with great interest, the paper by Stemer et al. titled
'Acute embolization of ruptured brain arteriovenous malformations' [1].
The authors describe a cohort of 21 patients with ruptured intracranial
arteriovenous malformations (AVM) who were treated with endovascular Onyx
(ev3, Irvine, California, USA) embolization in the acute phase following
hemorrhage. The median interval from hemorrhagic presentation to treatment
was 4 days (range 0-19 days). Thirteen patients received a single
treatment (62%), and eight patients were treated in more than one stage
(38%). Complete occlusion was achieved in 11 patients (52%) including
seven in one stage and four in multiple stages. There were two
asymptomatic intraprocedural complications (10%) as well as two
mortalities unrelated to treatment (10%).
Excluding three patients lost to follow-up and six patients who
underwent post-embolization surgical resection, 12 patients had
angiographic follow-up at a mean interval of 7.5 months. It would be
interesting to know the number of AVMs, if any, which had post-
embolization recanalization at follow-up as this is known to occur at
varying time intervals following endovascular treatment. Despite high
levels of initial enthusiasm for complete AVM cure with standalone
endovascular embolization following the advent and subsequent widespread
therapeutic use of permanent liquid embolic agents, especially Onyx, the
role of embolization in the overall management of AVMs remains largely
adjunctive.
Studies reporting high rates of complete AVM obliteration with
embolization alone, approaching 50%, were subject to significant selection
biases [2]. Total obliteration rates of 10-20% with embolization alone are
more reflective of less selected AVM cohorts [3]. The effect of partial
AVM treatment on the subsequent hemorrhage risk is still controversial
with conflicting studies reporting improved and worsened outcomes of
incompletely obliterated AVMs. With increasing evidence that embolization
reduces AVM obliteration rates following radiosurgery, judicious use of
endovascular therapy for AVMs is crucial to the optimal long-term
management of these complex vascular lesions [4-6].
Early natural history studies of AVMs did not distinguish ruptured
from unruptured lesions. However, several recent studies in the past
decade have repeatedly demonstrated that the hemorrhage risk of ruptured
AVMs is significantly higher than the hemorrhage risk of unruptured ones
[7]. Unlike intracranial aneurysms, for which the risk of acute repeat
hemorrhage following initial rupture is well described, the acute
rehemorrhage rate of ruptured AVMs is poorly defined. In a recent meta-
analysis of over 3900 patients, Gross et al. reported an annual hemorrhage
risk of 4.5% for ruptured AVMs compared to 2.2% for unruptured lesions
[8]. A follow-up duration of less than one year, such as in this study, is
inadequate to compare treatment outcomes to the natural history.
In summary, the authors should be congratulated for demonstrating the
feasibility and safety of endovascular Onyx embolization for the treatment
of acutely ruptured AVMs. As the authors note, the study is significantly
limited by the relatively small number of patients with angiographic
follow-up and the relatively short duration of follow-up. Therefore it
remains to be determined in larger cohorts with longer follow-up whether
the strategy of acute embolization for ruptured AVMs is superior to
current approaches which are largely conservative in the acute post-
hemorrhage phase.
References
1. Stemer, A.B., W.O. Bank, R.A. Armonda, A.H. Liu, D.W. Herzig, and
R.S. Bell, Acute embolization of ruptured brain arteriovenous
malformations. J Neurointerv Surg, 2013. 5(3): p. 196-200.
2. Saatci, I., S. Geyik, K. Yavuz, and H.S. Cekirge, Endovascular
treatment of brain arteriovenous malformations with prolonged intranidal
Onyx injection technique: long-term results in 350 consecutive patients
with completed endovascular treatment course. J Neurosurg, 2011. 115(1):
p. 78-88.
3. van Rooij, W.J., M. Sluzewski, and G.N. Beute, Brain AVM embolization
with Onyx. AJNR Am J Neuroradiol, 2007. 28(1): p. 172-7; discussion 178.
4. Schwyzer, L., C.P. Yen, A. Evans, S. Zavoian, and L. Steiner, Long-term
Results of Gamma Knife Surgery for Partially Embolized Arteriovenous
Malformations. Neurosurgery, 2012. 71(6): p. 1139-48.
5. Ding, D., C.P. Yen, Z. Xu, R.M. Starke, and J.P. Sheehan, Radiosurgery
for patients with unruptured intracranial arteriovenous malformations. J
Neurosurg, 2013.
6. Andrade-Souza, Y.M., M. Ramani, D. Scora, M.N. Tsao, K. terBrugge, and
M.L. Schwartz, Embolization before radiosurgery reduces the obliteration
rate of arteriovenous malformations. Neurosurgery, 2007. 60(3): p. 443-51;
discussion 451-2.
7. Stapf, C., H. Mast, R.R. Sciacca, J.H. Choi, A.V. Khaw, E.S. Connolly,
J. Pile-Spellman, and J.P. Mohr, Predictors of hemorrhage in patients with
untreated brain arteriovenous malformation. Neurology, 2006. 66(9): p.
1350-5.
8. Gross, B.A. and R. Du, Natural history of cerebral arteriovenous
malformations: a meta-analysis. J Neurosurg, 2013. 118(2): p. 437-43.
I am glad to see that my letter has piqued the interest of
interventional neuroradiologists like Dr. Jagadeesan. I agree with him
that no one should be running a fellowship that does not have the volume
to expose trainees to enough cases so that they may obtain the necessary
experience to practice safely. However, I think he has misunderstood my
point. As I stated about the original piece, "I have no objection to the
lo...
I am glad to see that my letter has piqued the interest of
interventional neuroradiologists like Dr. Jagadeesan. I agree with him
that no one should be running a fellowship that does not have the volume
to expose trainees to enough cases so that they may obtain the necessary
experience to practice safely. However, I think he has misunderstood my
point. As I stated about the original piece, "I have no objection to the
logic and opinions expressed, and actually have no opinion on the issue
for or against these fellowships." My only request was for the authors of
the original article to disclose the fact (as Dr. Jagadeesan has nicely
done in his own letter) that they may have potential conflicts of interest
by way of already completed and reaping the potential rewards of the very
same fellowship training that they now advocate curtailing, so that the
reader may use this information when making up his or her own mind. I have
no interest in standing between interventional neuroradiologists and their
patients (unless one is trying to run over the other, in which case I hope
I could intervene). As far as taxi drivers, I would applaud their
specialty if one disclosed that he gotten his driver's license from the
black market instead of completing the required training and tests -
indeed, that information might affect my decision to ride in his or
another cab.
We read with great interest the article by Turk et al[1] assessing
the safety and efficacy of endovascular stroke intervention based on CT
perfusion (CTP) criteria. The authors are to be congratulated for this
excellent report and for achieving remarkably high rates of favorable
outcomes (42%) in stroke patients with poor neurological sta...
We read with great interest the article by Turk et al[1] assessing
the safety and efficacy of endovascular stroke intervention based on CT
perfusion (CTP) criteria. The authors are to be congratulated for this
excellent report and for achieving remarkably high rates of favorable
outcomes (42%) in stroke patients with poor neurological status (mean
NIHSS, 18.2). They further categorize their patient population based on
time from symptom onset and clearly show that patients treated after 8 h
had no difference in outcomes or mortality than those treated before 8 h.
The fact that time from symptom onset to intervention was as long as 16.4
h in the late group (>8h) lends further credence to their findings
because the extent of salvageable brain tissue and the prospect of
improvement significantly decrease with delayed recanalization.[2-4] This
report adds substantially to the growing body of literature supporting the
use of CTP in stroke patients and reinforces what we have always believed;
specifically, CTP can optimize and guide patient selection for
intraarterial therapy based on an individual's physiological parameters
namely the extent of salvageable ischemic penumbra.
Although we agree with the authors about the merits of CTP and stress
the importance of their results, we would like to bring to their attention
that their conclusion may not be totally supported by the presented data.
The authors have compared functional outcomes in patients treated <8 h
and >8 h after symptom onset. Although all patients were selected for
endovascular stroke intervention based on CTP criteria, they conclude that
"physiologic imaging-guided patient selection rather than time for
endovascular reperfusion in ischemic stroke may be effective and safe". We
believe the only way to reach such a conclusion is to compare two groups
of patients, one selected based on CTP criteria and the other based on
time from symptom onset. Indeed, the authors do not discuss the study by
Hassan et al[5] published in 2010 that retrospectively compared 69
patients undergoing CTP-guided and 127 patients undergoing time-guided
endovascular treatment. The authors of this study found no incremental
benefit with the use of CTP, with similar rates of recanalization,
intracranial hemorrhage, favorable outcomes, and in-hospital mortality in
both groups. It should be noted, however, that only 40% of patients in
their study underwent mechanical thrombectomy and that CTP-guided
treatment at the primary author's institution was compared to time-guided
treatment at a different institution, which could have influenced their
results. Still, this is to our knowledge the only study that has compared
time-guided to CTP-guide patient selection for acute stroke intervention.
Randomized controlled trials comparing the 2 strategies are needed
especially that many prominent centers still have not adopted CTP as a
screening tool in this setting.
We would also like to highlight some of the potential shortcomings
associated with CTP that were not discussed in this study. The inter-
observer variability remains a great concern with CTP.[6] Additionally,
the optimal post-processing algorithm for defining penumbra and core
infarct have yet to be determined, and thresholds for guiding therapy are
still under investigation.[7] The variation in reconstruction of CTP
images and qualitative interpretation of salvageable tissue may lead to
selection of a relatively heterogeneous population, leading to the
inclusion of patients with limited salvageable tissue. False negatives and
non interpretable imaging can occur with CTP due to low cardiac output,
inappropriate slow rate of bolus administration, contrast extravasation in
the subcutaneous tissue, patient movement, and operator inexperience.
Finally, despite the potential caveats of CTP imaging , Turk et al[1]
have clearly demonstrated that CTP allows effective treatment of many
patients who otherwise would be destined for supportive management or end
of life care due to presentation outside of the therapeutic window. We
commend the authors for their rigorous work and await similar
contributions that will help us determine the best approach for patient
selection for acute stroke intervention.
References
1. Turk AS, Magarick JA, Frei D, et al. CT perfusion-guided patient
selection for endovascular recanalization in acute ischemic stroke: a
multicenter study. J Neurointerv Surg 2012 doi: neurintsurg-2012-010491
[pii]
10.1136/neurintsurg-2012-010491[published Online First: Epub Date]|.
2. Wardlaw JM, Murray V, Berge E, et al. Recombinant tissue plasminogen
activator for acute ischaemic stroke: an updated systematic review and
meta-analysis. Lancet 2012;379(9834):2364-72 doi: S0140-6736(12)60738-7
[pii]
10.1016/S0140-6736(12)60738-7[published Online First: Epub Date]|.
3. Hesselmann V, Niederstadt T, Dziewas R, et al. Reperfusion by combined
thrombolysis and mechanical thrombectomy in acute stroke: effect of
collateralization, mismatch, and time to and grade of recanalization on
clinical and tissue outcome. AJNR Am J Neuroradiol 2012;33(2):336-42 doi:
ajnr.A2746 [pii]
10.3174/ajnr.A2746[published Online First: Epub Date]|.
4. Vergouwen MD, Algra A, Pfefferkorn T, et al. Time Is Brain(stem) in
Basilar Artery Occlusion. Stroke 2012 doi: STROKEAHA.112.666867 [pii]
10.1161/STROKEAHA.112.666867[published Online First: Epub Date]|.
5. Hassan AE, Zacharatos H, Rodriguez GJ, et al. A comparison of Computed
Tomography perfusion-guided and time-guided endovascular treatments for
patients with acute ischemic stroke. Stroke 2010;41(8):1673-8 doi:
STROKEAHA.110.586685 [pii]
10.1161/STROKEAHA.110.586685[published Online First: Epub Date]|.
6. Hassan AE, Zacharatos H, Chaudhry SA, et al. Agreement in endovascular
thrombolysis patient selection based on interpretation of presenting CT
and CT-P changes in ischemic stroke patients. Neurocrit Care 2012;16(1):88
-94 doi: 10.1007/s12028-011-9577-9[published Online First: Epub Date]|.
7. Amenta PS, Ali MS, Dumont AS, et al. Computed tomography perfusion-
based selection of patients for endovascular recanalization. Neurosurg
Focus 2011;30(6):E6 doi: 10.3171/2011.4.FOCUS10296[published Online First:
Epub Date]|.
As a participant in the creation of the original ACGME ESNR
fellowship training standards, I read the article concerning fellowship
suspension with great interest (1). The paper is timely and thorough. It
is unfortunate that the Neurointerventional world is dealing with so many
unknowns. We do not seem to know how many we are, where we work, what we
do, or where we were trained. The problem is very well summarized at...
As a participant in the creation of the original ACGME ESNR
fellowship training standards, I read the article concerning fellowship
suspension with great interest (1). The paper is timely and thorough. It
is unfortunate that the Neurointerventional world is dealing with so many
unknowns. We do not seem to know how many we are, where we work, what we
do, or where we were trained. The problem is very well summarized at the
end of the paper. We seem to be spreading our patient population among
too many practitioners, which subsequently restricts the number of
patients available to each practitioner to stay in practice, make a
living, and be proficient.
The first line states: "The purpose of any training program is to
provide a supply of skilled workers to address an unmet demand for their
services." The authors discuss numbers of procedures and extrapolate
implications but do not discuss what the training was that got these
people out into the world. Further, there is no clear statement as to
what these unmet needs are. These workers might perhaps be skilled in
certain areas, but not know anything about other subjects.
Adequacy of numbers is the primary thrust of the article. One
endovascular neurosurgeon can possibly cover 5 different hospitals by
themselves for aneurysms, AVMs etc., and could do 300 aneurysms per year
easily. Most, but not all, neurointerventional fellowships provide an
adequate number of aneurysms for training. But as correctly pointed out,
the numerous auxiliary procedures that are necessary to be proficient in
this profession, such as skull base tumor embolization, epistaxis,
vertebroplasty, nerve root block or ablation, are not routinely performed
at all institutions. AVMs might be completely ignored at many places.
Endovascular spinal procedures are rare.
The gaping hole in fellowship training is acute ischemic stroke.
Consistently complete training for all fellows continues to be a void in
our profession and a gap in the entire premise of this statement. It is
perfectly acceptable to produce specialists in aneurysm intervention as
well as vertebroplasty, but we should not count them all in the same
bucket and presume we have enough people to cover the nation for stroke.
Everyone does not do everything nor do they want to. Many fellowship
programs have inadequate caseload and resultant inadequate or poor
training in acute stroke treatment. We should not just expect this
specialized training to magically appear in fellowships where there is
inadequate case volume to begin with. Therefore, what is the true number
of interventionists that are available, trained, able, and willing to
treat strokes?
The need for trained physicians to treat stroke is not based upon the
number of strokes (as might be the case for aneurysms), but rather on the
number of hospitals that need stroke coverage. The issue with stroke
coverage is that there needs to be a minimal number of practitioners at
each hospital to take call 24/7/365, no matter the number of cases: 1 per
month or 1 per day. Another paper describes the necessity of stroke
coverage as 2-3 interventionists per center for 24/7/365 coverage (2),
contradicting the official SNIS stated position as well as EMTALA
(Emergency Medical Treatment and Active Labor Act) that states that no
requirement can be made for 24/7 coverage with less than 4 persons. If
there is a need for 200 hospitals to have 24/7/365 coverage, then there
needs to be at least 800 interventionists just at those hospitals alone.
The official SNIS position on stroke coverage is as follows: "Current
staffing levels at Comprehensive Stroke Centers will rarely allow
continuous immediate coverage for IA stroke therapy at all times, 365 days
a year. Instantly available coverage on a continuous basis 24/7/365
should not be expected with fewer than 4 persons. Until adequate staffing
levels are achieved, continuously available catheter-directed intra-
arterial emergency stroke therapy is considered the "ideal", but is not
mandatory in order to be classified as Comprehensive Stroke Center.
Therefore, in agreement with federal regulations, IA stroke therapy might
be available only a portion of the time as determined by local hospital
conditions and staffing levels of qualified and appropriately trained
personnel, and the institution still qualify as a Comprehensive Stroke
Center." (SNIS executive committee, John Barr president, 2005). As we all
know, there are very few hospitals that have 4 neurointerventionists.
There are probably fewer than 20 fellowships in the US that treat by
endovascular techniques more than 50 strokes per year. Maybe 10. Even
with 50 cases, a "fellow" can only "maybe" attain the SNIS mandated 10
cases as "primary operator" in his last few months. Thus, in the
remaining 60-70 fellowships (90%?), the trainees will not get the required
experience. There are numerous examples of fellowships that provide a
certificate of competency for everything "neurointerventional" where the
number of endovascular stroke cases can be counted on one hand... or one
finger. How will these fellows get sufficient training, experience, and
knowledge to have good outcomes when treating strokes when they are in
private practice?
Foremost, I hope that this call for a moratorium in fellowships will
be accompanied by an equally vigorous call for augmented and improved
stroke training for fellows and our members. A recent SNIS webinar
bemoaned the poor operator performance for intracranial stenting during
SAMMPRIS. A recent article has documented "death and destruction" in
endovascular stroke therapy (3). The failure of SAMMPRIS and the stoppage
of IMS 3 only highlights the fact that we are not doing very well at this.
As we all used to believe, IMS 3 should have been a slam-dunk. SNIS/SVIN
should offer specialized intensive training courses that are, in actual
fact, a responsibility of our professional organizations. Our societies
need a plan for improved training and continuing education for our fellows
and members in addition to a moratorium.
References
1) Fiorella D, Hirsch JA, Woo HH, et al. Should neurointerventional
fellowship training be suspended indefinitely? J NeuroIntervent Surg
2012;4:315-318
2) Zaidat OO, Lazzaro M, McGinley E, et al. Demand-supply of
neurointerventionalists for endovascular ischemic stroke therapy.
Neurology 2012;79 (Suppl 1):S35-S41.
3) Cloft HJ. Death and Destruction in the Intra-Arterial Battle with
Acute Ischemic
Stroke. AJNR Am J Neuroradiol 32:1767-70.
Hirsh and Meyers espouse that same party line of the many private non
-governmental agencies (and academics who will personally benefit from
this program) who wish to impose private interest group-unproven corporate
interests upon practicing physicians. They continue to state MOC is
"voluntary" and then describe the many ways these "non-profit"
corporations (who earn handsomely and have over $400 million in assets and
as g...
Hirsh and Meyers espouse that same party line of the many private non
-governmental agencies (and academics who will personally benefit from
this program) who wish to impose private interest group-unproven corporate
interests upon practicing physicians. They continue to state MOC is
"voluntary" and then describe the many ways these "non-profit"
corporations (who earn handsomely and have over $400 million in assets and
as great yearly gross receipts!) will see this product forced on
physicians. HOWEVER, Working physicians do not want or even see any value
in this unproven imposition:
The American Medical Association (AMA) developed the Physician's
Recognition Award (PRA) in the late 1960's as the validation program for
Continuing Medical Education (CME), embraced by most, but not all states,
to validate physician "lifelong learning" as the educational component of
re-licensure. Recently, the Federation of State Medical Boards (FSMB),
Inc., a multimillion dollar, non-profit and non-governmental corporation,
targeted the State of Ohio as the first of 11 pilot states to implement
their corporate brand of MOL (Ohio., Calif., Colo., Del., Iowa, Mass.,
Mississippi, Okla., Ore., Va., Wis.).
On May 19, 2012, the Ohio State Medical Association, as the first Ohio
physician organization, formally resolved at the state meeting to oppose
the FSMB MOL program. (1) OSMA recognized early that FSMB MOL was the
unwarranted regulatory capture of physician licensure: the act of securing
corporate income through legislation. (2) An intense battle over FSMB MOL
ensued within the State Medical Board of Ohio (SMBO), zealously led by two
FSMB board members, who also occupied the SMBO Executive Director and one
senior Board member positions. On October 5, 2012, the OSMA drafted with
10 other state medical associations, representing over 15,000 physicians,
a formal resolution of opposition directed to the SMBO. (3) The defeat of
the FSMB MOL proposal by SMBO vote followed on October 11, 2012.
In the aftermath, the two FSMB board members serving on the SMBO were
formally reviewed. The Executive Director of the SMBO was ousted October
12th and formal investigations regarding violations of conflict of
interests continue regarding the senior SMBO member. (4) Subsequent
communications with legal offices of the SMBO and OSMA concluded that: 1)
FSMB MOL was not advocated by any other corporate, government or consumer
groups, no deficiency of AMA PRA CME programs or physician competency
issues were identified in Ohio and 2) FSMB MOL initiative appeared solely
promulgated by the FSMB as a corporate mandate. It continues to be
actively advocated by FSMB in 9 states and must be either fought or
approved in each state. FSMB MOL serves primarily corporate coffers and
false reassurance through testing vs CME. Effective physician opposition
is primarily possible via grass-roots resolutions at state level. We must
inform and support all state organizations at this time regarding FSMB
MOL, using this "Ohio experience" as evidence and instruction in opposing
this regulatory capture of physicians, solely for corporate profits. (5)
The assertions by the Certification industrial complex including the ABMS
that MOC and MOL are "Done deals" is simple propaganda-nothing more!
References:
1) Ohio State Medical Association Statement on MOL. Available at:
http://www.osma.org/files/pdf/facts-maintenance-of-licensure-final-.pdf
Accessed 10/27/12
2)Kempen PM: Maintenance of Certification (MOC), Maintenance of
Licensure (MOL), and Continuing Medical Education (CME):the Regulatory
Capture of Medicine. Journal of American Physicians and Surgeons 2012;
17:72-5. Available at: http://www.jpands.org/vol17no3/kempen.pdf Accessed
10/27/12
3) Kumar D et al: Joint letter from 11 medical societies to the SMBO.
Available at:
http://www.itraumaohio.org/aws/OACEP/asset_manager/get_file/54757/2012.10.5_joint_mol_letter_to_medical_board.pdf
Accessed 10/27/12
4) Alan Johnson In The Columbus Dispatch Thursday October 18, 2012 6:07
AM: State medical board ousts chief Available at:
http://www.dispatch.com/content/stories/local/2012/10/18/state-medical-
board-ousts-chief.html Accessed 10/27/12
5)Kempen PM: What to do about MOC and MOL? Available at:
http://www.youtube.com/watch?v=WRS15Dmsk7E Accessed Nov 1, 2012
I am not a neurosurgeon, neuroradiologist, nor interventionalist. In
fact, I am not a regular reader of your journal. However, the article
entitled "Should Neurointerventional Fellowship Training Be Suspended
Indefinitely?" by David Fiorella, et al., was brought to my attention,
unsolicited, by several different medical web sites. I have no objection
to the logic and opinions expressed, and actually h...
I am not a neurosurgeon, neuroradiologist, nor interventionalist. In
fact, I am not a regular reader of your journal. However, the article
entitled "Should Neurointerventional Fellowship Training Be Suspended
Indefinitely?" by David Fiorella, et al., was brought to my attention,
unsolicited, by several different medical web sites. I have no objection
to the logic and opinions expressed, and actually have no opinion on the
issue for or against these fellowships. But I feel I must register my
shock at what I see as a glaring omission by the journal.
The many authors do indicate their respective affiliations, and
cumulatively list in their disclosure, "Competing interests: None." The
most important disclosure, however, is not listed anywhere as a conflict
of interest. Namely, how many of the authors are practicing, already
fellowship-trained neurointerventionalists? In order to get a sense of any
potential bias, I think the reader would want to know this fact about each
author. Certainly, if most (or all) of the authors currently practice as
neurointerventionalists, regardless of their arguments, some readers might
feel that their position and recommendations simply represent an effort to
restrict competition for their own advantage, and that the journal has
given them a platform to advance this protectionist goal. If General
Motors found themselves with a surplus of unsold cars and made the
argument that there were too many autos already on the road, I might agree
with that statement. But if their proposed solution was to ban further
manufacture of cars so that they would have less competition unloading
their inventories, I might object. Perhaps another company could produce
cars that would be better (more efficient, safer, faster, etc.) and
preventing them from doing so would hurt consumers, who would have fewer
options. Similarly, while the authors may have correctly described the
current problem (too many neurointerventionalists with not enough cases)
their proposed solution (blocking further entries into the field) could be
seen as self-serving. After all, maybe there are potential trainees or
training programs who would introduce better practitioners (more
efficient, safer, faster, etc.) into the market place, pressuring current
(and future) neurointerventionalists to continue to improve the services
they now deliver.
I invite each of the authors of the original article (and of any
subsequent supportive letters) to make that disclosure: who among you are
neurointerventionalists who have already enjoyed the benefits of
fellowship training? Like any disclosure, this should not lessen your
stated arguments; rather it will just allow the reader to know whence your
recommendations are coming from. It only seems fair to be transparent. I'm
just saying.
To the editor,
The interesting paper by Li et al. reports an important series of cases treated appropriately and carefully followed-up, but unfortunately the diagnosis may not be correct in all cases. Fusiform aneurysms appearing in angiograms may represent a variety of different histopathological pictures, including dissection, but also other types of aneurysms. A light to this question, quite recurrent in my p...
Dear Dr. Tarr,
We read with interest the recent editorial by Fiorella et al., entitled "Should Neurointerventional fellowship training be suspended indefinitely?", detailing the potential hazards of neurointerventional (NI) overtraining in the United States (US).1 We face similar issues in Australia pertaining to our own current NI workforce demand and NI trainee employment outlook.
The landmass of Aus...
We read with interest Dr. Ding's response to our manuscript, "Angioarchitectural features associated with hemorrhagic presentation in pediatric cerebral arteriovenous malformations," and we thank him for his gracious comments. In response to his question regarding whether brain AVM angioarchitecture influences our particular treatment strategy, we would point out that the overwhelming majority of our pediatric patients wi...
I have read, with great interest, the paper by Ellis et al. titled 'Angioarchitectural features associated with hemorrhagic presentation in pediatric cerebral arteriovenous malformations [1]. The authors retrospectively reviewed the angiographic features of 135 pediatric patients, mean age 10.1 years (range 0-19 years), who were referred to Hospital for Sick Children in Toronto, Canada and Boston Children's Hospital ove...
I have read, with great interest, the paper by Stemer et al. titled 'Acute embolization of ruptured brain arteriovenous malformations' [1]. The authors describe a cohort of 21 patients with ruptured intracranial arteriovenous malformations (AVM) who were treated with endovascular Onyx (ev3, Irvine, California, USA) embolization in the acute phase following hemorrhage. The median interval from hemorrhagic presentation to...
I am glad to see that my letter has piqued the interest of interventional neuroradiologists like Dr. Jagadeesan. I agree with him that no one should be running a fellowship that does not have the volume to expose trainees to enough cases so that they may obtain the necessary experience to practice safely. However, I think he has misunderstood my point. As I stated about the original piece, "I have no objection to the lo...
Nohra Chalouhi M.D., Stavropoula Tjoumakaris M.D.,and Pascal Jabbour M.D.
We read with great interest the article by Turk et al[1] assessing the safety and efficacy of endovascular stroke intervention based on CT perfusion (CTP) criteria. The authors are to be congratulated for this excellent report and for achieving remarkably high rates of favorable outcomes (42%) in stroke patients with poor neurological sta...
As a participant in the creation of the original ACGME ESNR fellowship training standards, I read the article concerning fellowship suspension with great interest (1). The paper is timely and thorough. It is unfortunate that the Neurointerventional world is dealing with so many unknowns. We do not seem to know how many we are, where we work, what we do, or where we were trained. The problem is very well summarized at...
Hirsh and Meyers espouse that same party line of the many private non -governmental agencies (and academics who will personally benefit from this program) who wish to impose private interest group-unproven corporate interests upon practicing physicians. They continue to state MOC is "voluntary" and then describe the many ways these "non-profit" corporations (who earn handsomely and have over $400 million in assets and as g...
Dear Sir:
I am not a neurosurgeon, neuroradiologist, nor interventionalist. In fact, I am not a regular reader of your journal. However, the article entitled "Should Neurointerventional Fellowship Training Be Suspended Indefinitely?" by David Fiorella, et al., was brought to my attention, unsolicited, by several different medical web sites. I have no objection to the logic and opinions expressed, and actually h...
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