We thank Coutinho and colleagues for their comments on our
manuscript. They state that the 4% mortality associated with noninvasive
anticoagulant treatment in the International Study on Cerebral Vein and
Dural Sinus Thrombosis (ISCVT) is superior to our observed mortality rate
of 15% (2 of 13 patients). The ISCVT is a large prospective trial, which
is detailed in the Discussion of our article. A direct comparison of
m...
We thank Coutinho and colleagues for their comments on our
manuscript. They state that the 4% mortality associated with noninvasive
anticoagulant treatment in the International Study on Cerebral Vein and
Dural Sinus Thrombosis (ISCVT) is superior to our observed mortality rate
of 15% (2 of 13 patients). The ISCVT is a large prospective trial, which
is detailed in the Discussion of our article. A direct comparison of
mortality rates between ISCVT and our small case series is not meaningful.
In our series the 15% mortality rate was related to the damage that was
already done by venous sinus thrombosis. These patients were already
neurologically devastated before our intervention—their deaths were not
a result of the procedure. It is even possible that outcomes would have
been better had we intervened in those patients sooner. We have been
involved in several cases where patients were managed with anticoagulation
initially for some time but continued to worsen. By the time mechanical
thrombectomy was brought to the table, they were already devastated.
Coutinho and colleagues state that in the absence of additional risk
factors for a poor prognosis, they would not treat any patients with
endovascular therapy. However, they do not consider the problems
associated with long-term refractory headaches often experienced by sinus
thrombosis patients. In our series all 6 patients who presented primarily
with severe headaches experienced complete and immediate resolution of
their headaches after mechanical thrombectomy.
Coutinho et al. also point out that there was no control group in our
series and that follow up was incomplete. These issues of course reflect
the retrospective nature of this case series; it was not a randomized
controlled trial. The key point of our report is that endovascular
therapy for venous sinus thrombosis can be performed with minimal risk in
experienced hands. Mechanical intervention markedly reduces the volume of
thrombus and quickly restores flow. Once flow is established, the residual
thrombus responds more completely and more quickly to systemic
anticoagulation. We believe this approach greatly reduces the duration and
severity of symptoms and can shorten hospital stays and the required
convalescence period.
Shervin R. Dashti, M.D.
Louisville, Kentucky
Cameron G. McDougall, M.D.
Phoenix, Arizona
The paper by Dashti et al. (1) describes 13 patients who received
mechanical thrombectomy with the AngioJet device as first line treatment
for cerebral venous thrombosis (CVT). Mechanical thrombectomy is a
promising alternative to endovascular thrombolysis with thrombolytic
drugs. Hemorrhagic infarcts are common among CVT patients and it is
plausible - although unproven - that mechanical thrombec...
The paper by Dashti et al. (1) describes 13 patients who received
mechanical thrombectomy with the AngioJet device as first line treatment
for cerebral venous thrombosis (CVT). Mechanical thrombectomy is a
promising alternative to endovascular thrombolysis with thrombolytic
drugs. Hemorrhagic infarcts are common among CVT patients and it is
plausible - although unproven - that mechanical thrombectomy gives less
hemorrhagic complications.
There are however some issues that render the authors' suggestion to
use mechanical thrombectomy as a first line treatment for CVT untenable.
First, the paper gives insufficient information about the baseline
condition of the patients, especially the presence of intracranial
hemorrhages before the procedure. The Glasgow Coma Scale was optimal in 7
patients. In the absence of additional risk factors for a poor prognosis -
not mentioned by the authors - we would not treat these patients with
endovascular therapy. Second, follow-up is incomplete, and there is no
control group in the study. Without a control group it is impossible to
conclude that endovascular treatment is better than standard treatment.
The prognosis of CVT after heparin treatment is usually good. In the
'International study on cerebral vein and dural sinus thrombosis' (ISCVT),
a prospective study of 624 patients, mortality at discharge was 4% with
non-invasive anticoagulant treatment (2). This is better than the 15% peri
-operative mortality (2 out of 13) reported by Dashti et al.
We therefore disagree with the suggestion that mechanical
thrombectomy should be considered as first line treatment for CVT. In
patients without risk factors for a poor prognosis, anticoagulant
treatment according to international guidelines (3,4) is usually
effective. Patients with one or more risk factors may benefit from
endovascular treatment, but there are no appropriately controlled studies.
Therefore, we recently launched the TO-ACT study (Thrombolysis Or
Anticoagulation for Cerebral venous Thrombosis), an international
randomized trial (www.clinicaltrials.gov; NCT01204333). Patients are
eligible if they have severe CVT, as defined by the risk factors:
intracranial hemorrhage, coma, mental status disorder or thrombosis of the
deep venous system. The type of endovascular treatment is to be decided by
the local investigator and may be pharmacological, mechanical, or a
combination. A sensitivity analysis of the type of endovascular
thrombolysis is planned. More information about the trial is available at
www.to-act-trial.org.
JM Coutinho, R van den Berg, SM Zuurbier, CB Majoie and J Stam
Academic Medical Center, Amsterdam, the Netherlands
j.coutinho@amc.uva.nl
References
1. Dashti SR, Hu YC, Yao T, Fiorella D, Mitha AP, Albuquerque FC,
McDougall CG. Mechanical thrombectomy as first-line treatment for venous
sinus thrombosis: technical considerations and preliminary results using
the AngioJet device. J Neurointerv Surg. 2011 Dec 5. [Epub ahead of print]
2. Ferro JM, Canhao P, Stam J, Bousser MG, Barinagarrementeria F.
Prognosis of
cerebral vein and dural sinus thrombosis: results of the International
Study on
Cerebral Vein and Dural Sinus Thrombosis (ISCVT). Stroke. 2004;35:664-70.
3. Einhaupl K, Stam J, Bousser MG, De Bruijn SF, Ferro JM, Martinelli
I, Masuhr F; European Federation of Neurological Societies. EFNS guideline
on the treatment of cerebral venous and sinus thrombosis in adult
patients. Eur J Neurol. 2010 Oct;17(10):1229-35.
4. Saposnik G, Barinagarrementeria F, Brown RD Jr, Bushnell CD,
Cucchiara B, Cushman M, deVeber G, Ferro JM, Tsai FY; American Heart
Association Stroke Council and the Council on Epidemiology and Prevention.
Diagnosis and management of cerebral venous thrombosis: a statement for
healthcare professionals from the American Heart Association/American
Stroke Association. Stroke. 2011 Apr;42(4):1158-92
As the first author (and the senior author) I am wholly responsible
for any errors in the paper, including errors of attribution. I apologize
first to our readers, and second to Dr. Altes, whose contributions are
significant and are of continuing value.
I read with interest the paper by Kerber, et al. entitled "1-Hexyl n-
cyanoacrylate compound (Neucrylate_AN), a new berry aneurysm treatment.
II. Rabbit implant studies: technique and histology." (1) As suggested by
the title, the paper focuses on the preclinical evaluation of a new device
in a rabbit model. However, the references and discussion are misleading
and may well confuse researchers inten...
I read with interest the paper by Kerber, et al. entitled "1-Hexyl n-
cyanoacrylate compound (Neucrylate_AN), a new berry aneurysm treatment.
II. Rabbit implant studies: technique and histology." (1) As suggested by
the title, the paper focuses on the preclinical evaluation of a new device
in a rabbit model. However, the references and discussion are misleading
and may well confuse researchers intending to reproduce the authors'
experiments.
The model used in the paper by Kerber, et al. is the widely-applied,
elastase-induced aneurysm model originally published by Altes, et al (2).
This simple model uses intraluminal elastase incubation to covert a
preexisting arterial lumen, the right common carotid artery, into an
aneurysmal stump. However, the methods of the paper by Kerber, et al. (1)
reference a completely distinct and different model published by
Miscolizik, et al (3). That latter model used extraluminal elastase
applied to arterial bifurcations, with resultant aneurysms forming acutely
but no chronic experiments described. Thus, readers of the paper by
Kerber, et al. should be advised that the periadventitial model of
Miskolczi, et al. was not, in fact utilized.
Further, the authors go on to note in their discussion that "In 1998,
Miskolczi, et al. developed a rabbit aneurysm model that provided a close
to ideal testing milieu for endovascular, particularly intra-arterial,
devices." In fact, I am unable to find a single study that has used that
the model of Miskolczi, et al. to test any device. Finally, Kerber, et
al. write that "An extensive literature has accumulated since Miskolczi's
original paper- a literature describing device behaviors and a wall
response to the introduction of foreign devices." The "extensive
literature" again has nothing to do with the paper by Miscolczi, but
rather describes work done using the elastase-induced model of Altes, et
al.
Clarity and precision are essential aspects of all medical
literature, both clinical and preclinical. Accurate references to animal
models will speed development of devices for the benefit of patients
suffering from intracranial aneurysms.
References
1. Kerber CW, Pakbaz RS, Hasteh F, et al. 1-Hexyl n-cyanoacrylate
compound (Neucrylate™ AN), a new berry aneurysm treatment. II.
Rabbit implant studies: technique and histology. J Neurointerv Surg. 2012
Jan 1;4(1):50-7. Epub 2011 Jun 8.
2. Altes TA, Cloft HJ, Short JG, et al.. 1999 ARRS Executive
Council Award. Creation of saccular aneurysms in the rabbit: a model
suitable for testing endovascular devices. American Roentgen Ray Society.
AJR Am J Roentgenol. 2000 Feb;174(2):349-54.
3. Miskolczi L, Guterman LR, Flaherty JD, et al. Saccular aneurysm
induction by elastase digestion of the arterial wall: a new animal model.
Neurosurgery. 1998 Sep;43(3):595-600; discussion 600-1.
Conflict of Interest:
Dr. Kallmes receives research support from MicroVention, Micrus, Penumbra, NFocus, Sequent, and eV3.
We greatly appreciate the input by Dr. Chandra and colleagues. Our
paper was a highly focused, empiric exercise to determine, based on
morphology alone, the potential for endoluminal implants for treatment of
aneurysms. There are myriad additional factors that, without question,
will affect the appropriateness of such devices for a given aneurysm,
including aneurysm rupture status, patient condition, age, tolerance of...
We greatly appreciate the input by Dr. Chandra and colleagues. Our
paper was a highly focused, empiric exercise to determine, based on
morphology alone, the potential for endoluminal implants for treatment of
aneurysms. There are myriad additional factors that, without question,
will affect the appropriateness of such devices for a given aneurysm,
including aneurysm rupture status, patient condition, age, tolerance of
antiplatelet agents, vascular access, and others that will become apparent
as these devices gain widespread use.
We welcome the comments by Dr. Chandra and colleagues regarding the
FDA approval status of the device. Of course, the work performed for
that paper was done long before the device was even submitted for FDA
approval, and represents a "thought experiment" rather than a clinical
trial. We, as they, assume that physicians are capable of reading the
package insert to determine the type of aneurysm for which the device was
specifically approved. We also assume that, as with many or most devices
approved under the Premarket Approval process, actual usage will extend
far beyond the "on-label" indication. We genuinely hope that such "off-
label" usage will be done in the setting of prospective, controlled
studies if at all possible, such studies that in the future might lead to
or away from FDA approval for expanded indications.
Response to "Estimating the proportion of intracranial aneurysms
likely to be amenable to treatment with the pipeline embolization device."
J Neurointerv Surg. 2011 Dec 2. [Epub ahead of print]
Ronil V. Chandra MBBS FRANZCR, Thabele M Leslie-Mazwi M.D and Joshua
A Hirsch M.D
Department of Interventional Neuroradiology/ Endovascular
Neurosurgery
Massachusetts Gen...
Response to "Estimating the proportion of intracranial aneurysms
likely to be amenable to treatment with the pipeline embolization device."
J Neurointerv Surg. 2011 Dec 2. [Epub ahead of print]
Ronil V. Chandra MBBS FRANZCR, Thabele M Leslie-Mazwi M.D and Joshua
A Hirsch M.D
Department of Interventional Neuroradiology/ Endovascular
Neurosurgery
Massachusetts General Hospital
Harvard Medical School
Corresponding Author:
Joshua A Hirsch, M.D
Department of Interventional Neuroradiology/ Endovascular Neurosurgery
Massachusetts General Hospital
55 Fruit Street Gray 241
Boston MA 02114
E-mail: jahirsch@partners.org
We commend Brinjikji et al on their recent article estimating the
proportion of intracranial aneurysms likely to be amenable to treatment
with the pipeline embolization device (PED) 1. Based on aneurysm and
parent artery morphology, 47% of their consecutive sample of 200 aneurysms
could theoretically be treated by the PED.
We believe the paper might have been enhanced by consideration of the
current FDA approved indications for use of the PED. The approved
indications are for treatment of adults (22 years or greater) with large
or giant (10 mm or greater) wide-necked (4mm or greater or no discernible
neck) ICA aneurysms from the petrous to the superior hypophyseal segments.
At least 30% or more of the aneurysms that could be treated by the PED in
this theoretical analysis would have therefore been treated in an "off-
label" fashion. Put differently, in the cohort examined, ICA aneurysms
accounted for only 37% of the total sample. ICA aneurysms above the
superior hypophyseal segment were also included, as noted in Figure 1C.
Furthermore, ruptured aneurysms, which pose a relative contraindication
for use of the PED, were also included. The latter was clearly
acknowledged by the authors as a limitation and was required to increase
overall sample size.
Many unanswered questions regarding the PED remain, particularly
relating to rupture after treatment and long-term patency rates. Rather
than concluding that anatomically almost half of aneurysms presenting to a
tertiary neurovascular center could be treated with the PED, it might have
been prudent to highlight the FDA approved indications, and useful to
estimate the proportion of aneurysms that could be treated for these
approved indications.
References:
1. Brinjikji W, Cloft HJ, Fiorella D, et al. Estimating the
proportion of intracranial aneurysms likely to be amenable to treatment
with the pipeline embolization device. J Neurointerv Surg. 2011
In October 2011, JNIS published our article on the implementation of
the ICD-10 codes1. The final line of the paper was..." The authors favor
postponing implementation of ICD-10 and prefer a focus on core issues of
improving care and access.
The Centers for Medicare & Medicaid Services will require all health
professionals and facilities to transition to ICD-10 by October 2013. ICD-
10 is viewed as being more nuanced...
In October 2011, JNIS published our article on the implementation of
the ICD-10 codes1. The final line of the paper was..." The authors favor
postponing implementation of ICD-10 and prefer a focus on core issues of
improving care and access.
The Centers for Medicare & Medicaid Services will require all health
professionals and facilities to transition to ICD-10 by October 2013. ICD-
10 is viewed as being more nuanced and providing a greater level of detail
for what had led to an injury or illness. ICD-9 has 14,000 codes. As
outlined in the article, implementing ICD-10 nationally will require
tremendous allocation of resources. The upcoming change would require
practices learn 69,000 new codes for billing purposes.
The American Medical Association (AMA) apparently agrees. During the 65th
House of Delegate Interim Meeting of the AMA that occurred on November 15,
2011 2, delegates adopted a policy to work to stop implementation of the
new diagnosis coding set ICD-10. Alabama and Mississippi delegations, the
American Assn. of Clinical Urologists and the American Urological Assn.
introduced the resolution to stop ICD-10 implementation.
"The implementation of ICD-10 will create significant burdens on the
practice of medicine with no direct benefit to individual patients' care,"
said AMA President Peter W. Carmel, MD. "At a time when we are working to
get the best value possible for our health care dollar, this massive and
expensive undertaking will add administrative expense and create
unnecessary workflow disruptions. The timing could not be worse, as many
physicians are working to implement electronic health records into their
practices. We will continue working to help physicians keep their focus
where it should be -- on their patients."
The authors are penning this brief letter to the editor because we see
this AMA position as a relevant postscript to the paper.
References:
1. Manchikanti L, Falco FJE, Hirsch JA. Ready or not! Here comes ICD-10.
J NeuroIntervent Surg neurintsurg-2011-010155 Published Online First: 24
October 2011 doi:10.1136/neurintsurg-2011-010155
2. AMA Press Release: AMA Adopts New Policies During Final Day of
Semi-Annual Meeting. November 15, 2011.
http://www.amaassn.org/ama/pub/news/news/2011-11-15-ama-adopts-new-
policies.page
We thank Coutinho and colleagues for their comments on our manuscript. They state that the 4% mortality associated with noninvasive anticoagulant treatment in the International Study on Cerebral Vein and Dural Sinus Thrombosis (ISCVT) is superior to our observed mortality rate of 15% (2 of 13 patients). The ISCVT is a large prospective trial, which is detailed in the Discussion of our article. A direct comparison of m...
To the Editor:
The paper by Dashti et al. (1) describes 13 patients who received mechanical thrombectomy with the AngioJet device as first line treatment for cerebral venous thrombosis (CVT). Mechanical thrombectomy is a promising alternative to endovascular thrombolysis with thrombolytic drugs. Hemorrhagic infarcts are common among CVT patients and it is plausible - although unproven - that mechanical thrombec...
As the first author (and the senior author) I am wholly responsible for any errors in the paper, including errors of attribution. I apologize first to our readers, and second to Dr. Altes, whose contributions are significant and are of continuing value.
Charles Kerber M.D.
Conflict of Interest:
None declared
Dear Editor,
I read with interest the paper by Kerber, et al. entitled "1-Hexyl n- cyanoacrylate compound (Neucrylate_AN), a new berry aneurysm treatment. II. Rabbit implant studies: technique and histology." (1) As suggested by the title, the paper focuses on the preclinical evaluation of a new device in a rabbit model. However, the references and discussion are misleading and may well confuse researchers inten...
We greatly appreciate the input by Dr. Chandra and colleagues. Our paper was a highly focused, empiric exercise to determine, based on morphology alone, the potential for endoluminal implants for treatment of aneurysms. There are myriad additional factors that, without question, will affect the appropriateness of such devices for a given aneurysm, including aneurysm rupture status, patient condition, age, tolerance of...
Pipeline, aneurysms and the FDA
Response to "Estimating the proportion of intracranial aneurysms likely to be amenable to treatment with the pipeline embolization device." J Neurointerv Surg. 2011 Dec 2. [Epub ahead of print]
Ronil V. Chandra MBBS FRANZCR, Thabele M Leslie-Mazwi M.D and Joshua A Hirsch M.D
Department of Interventional Neuroradiology/ Endovascular Neurosurgery Massachusetts Gen...
In October 2011, JNIS published our article on the implementation of the ICD-10 codes1. The final line of the paper was..." The authors favor postponing implementation of ICD-10 and prefer a focus on core issues of improving care and access. The Centers for Medicare & Medicaid Services will require all health professionals and facilities to transition to ICD-10 by October 2013. ICD- 10 is viewed as being more nuanced...
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