Sunday, November 22, 2009

Thalamic lesion for diagnostic biopsy:Dr Nitin's patient








Friends,
This is 35 year old lady with progressive Left third nerve and right hemiparesis over 2 months. She had obstructive hydrocephalus for which she underwent a shunt.
Her CSF did not reveal any malignant cells.
I would like your opinion regarding how to biopsy this lesion. I am strongly considering lymphoma as possibility. She is not immunocompromised and has no other features of systemic involvement.
Unfortunately, our Stereotactic system is not working and patient cannot afford to move out to some other place.
She has a shunt.
I was considering 3 probable options:
1. Block the shunt, repeat scan after 6 hours and if further dilatation of ventricles, do an endoscopic biopsy. Her right frontal horn is still dilated.
2. Subtemporal approach.
3. Posterior transcallosal approach.

Would like your opinions regarding options.

Nitin Garg

Responses

As you suggested , one could do open biopsy of this lesion through several approaches,including frontal transcortical , transcallosal, subtemporal, parietal transcortical, even with modified Poppen's, approach,
I would rather do an endoscopic biopsy through the frontal horn
of right lateral ventricle
I think right lateral ventricle is not adequately decompressed with the VP shunt , which may need to be followed up

I have a suggestion about the discussion here, I think we should avoid showing the identity of the patients here, esp since this is an open forum
Pramod


Dear Nitin,
A very interesting case indeed. It is rather difficult from the images you have uploaded to ascertain the nature of the lesion. is it T2 dark witha spectro pattern favouring a lymphoma. If so you should strongly consider only a minimally invasive biopsy.Stereotaxy is ideal. I am not sure if an endoscopic approach via the right frontal horn will get you to the lesion. You could consider an image guided (ultrasound) biopsy if you have the apparatus.
Having siad that , I have my reservations on the presumptive diagnosis of a lymphoma. The lesion almost looks extra-axial in some of the cuts. More images would be better to determine the exact location to plan the approach. I may be wrong...but its worth a second look...all the best. Keep us posted on the progress.
ali

Some points reg. nitins case.
1.From limited images sent, to me it is an intrinsic lesion though as ali pointed out the left side thalamic- subthalamic- midbrain component has become exophytic in inferior aspect.
2. Fact that it is present in opp. thalamic region makes extrinsic diagnosis fairly less likely.
3. though lymphoma is a good bet based on periventricular intrinsic location and multiplicity another strong contender would be multifocal high grade glial mass-GBM perhaps. The large size of the left sided lesion in my opinioin makes me think of nonlymphomatous possibility.
4.Reg. approach, this is an ideal case for a)Frame based stereotactic surgery or b)Navigation based frameless stereotaxy.
I would be loathe to pursue craniotomy for just a biopsy, however for circumstances u have mentioned u need to do open surgery, I think post. transcallosal would not be my choice.
for subtemporal too it would require too much retraction of dominant temporal lobe and would risk jeoparadising Labbe'.
If u r comfortable with endoscopy go ahead but 6 hours will not suffice to dilate the ventricles and u would not see the lesion if the foramen monroe is not well dilated to pass thru safely.
Best wishes and keep us updated.
Satish
I agree with pramod that we should maintain anonymity of pt. identity.

Monday, November 16, 2009

Brain stem glioma: surgical approach?

14 year old girl with swallowing dysfunction, gaze paresis, facial nerve paresis, and mild quadriparesis.
[Please click the second last button on the you tube bottom bar to get full screen so that you can see in more detail]


Responses

Hi gk.
Good to see you become active again in this site after a hiatus
My thoughts.
1.It is a GBM medulla and pons extensively involved whatever the treatment options excercised, prognosis is grave with few weeks of survival, that being the case, would do everything to stabilise/improve quality of life.
2.would go with retro sigmoid app, need to work deep between cranial nerves, between lower cranial and 7,8th complex and then between 5th and 7th too. Realistically looks like a modest decompression is all that is possible without worsening neuro status.If you could hit the cyst at the summit would be good to reduce mass effect.
3.Temporal horns are getting big, is there significant hydro?
Another development in treating GBMS in general, Avastatin(anti angiogenic) has shown good promise adding few weeks to months for new/recurrent GBMs
Best wishes
Satish Sathya


Dear GK,
I think the retrosigmoid approach is the best to reach and do whatever decompresion that is possible. Probably decompressing the cyst and taking a biopsy is all I would attempt surgically , given the location and malignant nature of the lesion.
regards,
Maqsood

I agree with Dr Satish about its dismal prognosis regardless of the histopathology and extent of surgical resection.The tumor has significant ventrally exophytic component with areas showing some sort of margin from the brain stem.I would attempt to decompress this part of the tumor as well as the necrotic/cystic component through a retrosigmoid/far lateral approach

Pramod

Saturday, November 14, 2009

Olfactory groove meningioma with sinus invasion: Dr Maqsood's patient

Dear all,

This is a 48 yr old lady presenting with long standing anosmia of 8 years and recent adult onset seizures. She has no deficits except bilateral anosmia. Attached is the contrast MRI.
Kindly advise regarding the approach to take out the tumour completely including that of the paranasal sinus part.
I am planning an extended subfrontal approach.
Will an endoscopic endonasal approach be required to mobilise the lower component?
Regards

Dr.Maqsood





Hi Maqsood

The sinus component looks very large and there also appears to be hypertelorism. Is it evident clinically?

Have you considered a transnasal biopsy of the tumor before definitive surgery? It might not be a meningioma at all and even if it is it might be atypical or malignant.

Approach wise -
Extended subfrontal should be able to remove the tumor completely, IMO. Needless to say, reconstruction of the ACF base will have to be meticulous.

All the best with this one. Do let us know how it goes.

Regards

Arvind

Dear Chief, i think the extended subfrontal approach should be enough for the lower part as well, in this case.

Dr. Anirban Deep Banerjee
Neurosurgeon( NIMHANS)

Dear Dr Maqsood,
Thank you for illustrating such a case. To me bi-frontal, or even unilateral sub-frontal approach may be enough for the intracranial part. It is a more or less olfactory groove meningioma invading the base. If you notice, there is no major edema around, denoting the presence of an arachnoid plain which will make your dissection a little easier. The endonasal part may be approached from above, being intra-tumoral all the time during dissection; or may be approached with a combined endo nasal approach. The absence of signal voids intratumorally is a good sign of safe dissection. The most important is the plan of reconstruction, to provide a good base reconstruct and to prevent fistula formation later on. Lastly, a good look at the hormonal profile of the patient is a mandatory pre- and post-operative task.

Looking forward to hear from you.
Thanks
Mohamed Mohi Eldin , MB-BCH , M.Sc., MD
Prof. of Neurosurgery, Faculty of Medicine, Cairo University, Egypt,


Dear maqsood,
Agree that extened transfrontal is ideal for excising tumor completely.
I disagree need for biopsy, regardless of path, and beingn or atypiacal or even nonmeningioma makes no difference for need for complete excision,
Would take a large pericranial graft going behind skin incision and keep duragen plus or eqvivlaent as standby.
you would be surprised at the extent of access from above once intraranial component is removed.
Bewre of retraction, use less or none as bothfrontal lobes are already edematous, give good amount of steroids perioperatively.
Best wishes
Le us know the outcome.
One of our members(not sure if he is in the group) will be salivating seeing this MRI as it is a good and challenging case to do entitely endoscopically by extended transnasal approach(he is our desi amin kassam!).
Satish

Dear Maqsood,

I would agree with Dr Satish that an extended subfrontal approach would suffice in this case. the approach is able to access lesions in the frontoethmoids and nasal cavities. it is only when the leson involves the maxillary sinuses (which is not the case here) that an additional nasal approach (median maxillectomy or an endoscopic approach ) may be needed. This looks like a meningioma (and hence a biopsy is really not required)and I feel the bifrontal approach also provides for an excellent (and a very important) repair of the base.
all the best

Ali

Wednesday, June 24, 2009

How can I become a neurosurgeon? Should I take up General surgery first?

How can I become a neurosurgeon? Should I take up General surgery first?

This are exact same words that an MBBS student asked me the other day. He didnt tell me why he wanted to take up neurosurgery. He said he didn’t have any particular reason. Or maybe he didn’t want to tell me. In any case, it didn’t matter to me. Rational thought and expressed reasoning are not for everyone. For some it’s a calling and that’s fine. That's legit.

More importantly, we have to answer the second question: Should he take up general surgery first? If one has decided on taking neurosurgery as the end speciality, does one really need to go through three years of general surgical training before going through another round of entrance test and three more years of dedicated neurosurgery MCh training?

Lets break this question up…

Why is neurosurgery different from any other surgical field?

I feel that it is because the surgical motor skill that is required is quite different. It is unlike any of the catching-a-bleeder-tying-it-and-dissecting sort of thing that you do in general surgery.
Joints and muscles maketh the man!

May I take the liberty to propose a ‘Motor classification of surgeons” depending on the movements that are required at various joints?

1. If you are a ‘’shoulder-surgeon”, you are a good orthopedician
2. If you are an “elbow-surgeon”, take up general surgery, surgical gastro or cardiothoracic surgery
3. If you are a “wrist-surgeon”, its plastic surgery for you.
4. If you are good with fine finger generated surgical movements, neurosurgery and microvascular surgical fields may be good for you. You are basically restricted to metacarphalangeal and interphalangeal joints and rest of the joints are better stabilized and rested.

Neurosurgery is also not for the claustrophobic and the impatient. Expect narrow corridors and long hours on the operating microscope.

Neurosurgery is not for the morbidity-phobic surgeon either. It’s a fact that despite all the care one takes, one might end up injuring a patient forever… and many patients in a career. This happens in neurosurgery more than any other surgical field, mainly because of the density of functional tissue in the operative field.

Again back to the second question, does one really have to prime oneself with general surgery before taking up neurosurgery?

I believe that it is not necessary. If you have really decided on taking up neurosurgery, why not plunge straight in and save at least one year and be more focused on the subjects that matter – neurology, neuroradiology and operative neuroanatomy.
I am sure that many of you will not agree with me. What about ‘the broader outlook’ to patient management that a post MS general surgery resident is supposed to possess? May be there is a difference. May be you are better off managing a multiply injured patient. But how often has one managed a patient with blunt abdominal trauma and head injury and how often have you operated on a blunt injury patient while managing head injury? May be one can better diagnose the condtion and manage shock and resuscitate better. But does this really require three years of learning hernioraphy, mastectomy and abdominoperineal resection?

But there are caveats. It’s possible that a person who is post MBBS may have deep, nagging doubts throughout the five years whether the decision he has taken was too brave and whether he is up to it. And in the unlikely and unfortunate event of dropping out of the course, one will have nothing but MBBS left even if you have spent many years in the course. Yet, once he has completed the course he might be more focused on the subject and will have saved one year.

Skill, of course depends on the resident.

Lets see another angle to this question.

What type of residents do consultants prefer? For example, Sree chitra [SCTMST] favours post MS candidates of late. I’m not sure of the reasons. May be someone can enlighten on this point.

Friday, January 23, 2009

Is choice an illusion? What next for this nine year old girl?

This nine year old was investigated for 3 months history of defective vision and progressive headache and vomiting. She has primary optic atrophy in right eye [no PL]. She underwent a right ventriculoperitoneal shunt procedure in emergency setting for raised intracranial tension. She does well in school and has intact higher intellectual functions.



The preoperative scans are in the video. Pause the video to make your preoperative diagnoses. What might be the two most likely diagnoses?
Un-pause to see the post operative scans and suggest the next steps. What do you think are the treatment choices?

1)Imaging follow up, and if there is progression consider radiotherapy/Re-excision (which one?)
2)Radiotherapy now and re-excision if progression
3)Chemotherapy?
4)Re-excision now

For those of who with limited bandwidth, get a better connection to see the video! [just kidding... please see the attached jpegs: preop and post op]

Discussion on treatment options for thalamic low grade astrocytoma

What are the treatment options for this 30 year old lady with progressive hemiparesis.
Stereotactic biopsy is suggestive of low grade astrocytoma. Please advise. Am attaching post-GD MRI images.

-Nitin Garg





> From: brmrao1963 To: neurosurgery_ nimhans@. ..:
Sunday, January 18, 2009 11:55:26 AMSubject: [neurosurgery_ nimhans]
Re: Question of the week: Left thalamic low grade astrocytoma
>

Dear Nitin,
The images reveal a multifocallesion which is occupying a spread-out real estate in the ganglionic
and deep grey region abutting the internal capsule. While I do
operate micro surgically on thalamic lesions,the usual indication is
for a single mass. You can use a therapeutic test with dexamethasone
to find out if the weakness is reversible or not. If the deficit is
not reversible with steroids,then it is unlikely that surgery will
do so.In such a scenario, it maybe enough to subject her to
radiation and chemotherapy( some low grade astros do respond to
chemo)taking into consideration QOL issues.If there is a reasonable
chance of reversal of deficit you operate on her(transcallosal Vs
transcortical_ the lesion is spread-out quite laterally and may be
difficult to access transcallosally) . The point to be considered is
that the deficit can be created by a surgical adventure also!If you
have access to DTI please do it to map internal capsule fibers and
their course. If they are involved by the tumor, Surgery will not
have much to offer.

Ravi

To: neurosurgery_ nimhans@. ..: gopalakrishnanms@ ...: Sun, 18 Jan
2009 08:01:34 -0800Subject: Re: [neurosurgery_ nimhans] Re: Question
of the week: Left thalamic low grade astrocytoma

Dear Nitin,
Some questions worth pondering on ...
1. Is the histopath accurate? Does it warrant a review?
2. Is that low grade a sampling effect?
3. Is it possible that this multiple looking entity is finger like fiber tracking [and fiber destroying]
projections of a more sinister glioma or perhaps a different diagnosis considering the edge enhancement and central hypodensity,edema and may be acute (is it?) clinical history?

Regards,
Gopalakrishnan.

In neurosurgery_ nimhansATyahoogro ups.com, Dr.Nitin Garg wrote:
>
>
Thanks for the comments. On replying to both Prof Ravi Mohan Sir's
and GK's queries,

1. The onset was not acute. Patient developed the symptoms over 2-
3 weeks. The weakness is Grade 3-4.
2. During STB, the fluid obtained was xanthochromic. The biopsy
was from wall.
3. There has been no history of fever or other symptoms of TB.
4. Patient has been on steriods for almost 4 weeks. Neurologically
is status quo.
5. Shall try to get DTI.
>
Thanks.
Nitin


Hi Nitin,

I agree with GK , with images you provided(infiltrati ve,multifocal,
heterogenous lesion) , it is worthwhile reviewing the
histopathology, often sampling error from such a large tumor can
occur with stereotactic biopsies,biopsies from the periphery
sometimes show atypical astrocytes and pathologist may label it as
low grade astrocytoma. If this biopsy is from a representative area,
this is being a low grade tumor in a young patient , I would
certainly offer surgical treatment with an aim to maximum
debulking/excision without causing any more neurological deficits
(limitations -if tumor is infiltrative) .With tumor location, I would
intially consider doing a posterior interhemispheric
transventricular approach.But as Dr Ravi Mohan Rao rightly said,
lateral most portion will be difficult to reach with a midline
approach. The residual tumor could be reached through a separate
transcortical approach, aiming for gross total excision, esp if it
is turned out to be a low grade neoplasm.If it is a malignant
glioma , I would be less aggressive in the surgical approach.
Diffusion tensor image could be helpful in locating the white matter
tracts - esp for studying the location of internal capsule,optic
radiation etc.fMRI should be done to locate the speech and motor
areas, esp if you are planning for transcortical approach.
Primary aim of the surgery in this patient should be reducing the
tumor burden, not improving her neurological functions

Pramod

I thank all for the opinion.
Shall get the HPE reviewed and decide about the further mgt later. Shall keep you all informed about the progress.
Bye.
Nitin

[images and clinical details courtesy of Dr Nitin Garg]

Final update on this patient from Dr.Nitin

Friends,
I had posted a case of left thalamic tumor sometime in December. The STB was reported as grade 2 astrocytoma. The patient was planned for RT but was lost to follow up. She now came after 6 months with features of raised ICP. Rpt imaging showed significant frontal extension and midbrain and pontine extension of lesion.
We did a frontoparietal craniotomy, middle frontal gyrus approach and tumor decompression. Intraop impression was high grade glioma. Post-op she recovered with persistent hemiplegia and some aphasia.
The final histopathology has been reported as anaplastic oligodendroglioma. Looking back at the images and some of the comments posted, this looked malignant at that point and may have a sampling error. MRS would have helped (we dont have it in Bhopal at present).
presenting this case for followup.
Bye.
Nitin

Discussion on treatment options for growth hormone secreting residual pituitary macroadenoma

[please see previous post to see the clinical details of this discussion.

From: Arvind Bhateja To: neurosurgery nimhansATyahoogroup
Sent: Monday, December 22, 2008 11:48:42 AM
Subject: Re: Question of the week. Gh secreting residual.
Hi GKand Happy new year everyone!

In my opinion, the best option would be to re-operate this gentleman via an endoscopic trans-sphenoidal which should be able to decompress tumor around the carotid and cav sinuses.
To tackle the bleeding one would probably need to have thrombin solution or floseal.
Its probably the best way although many would find this option more painful.

If endoscopic is an issue an orbitozygomatic with an interdural approach to the cav sinus might also do the job, but it would be overkill for such a small residual.

Almost surely he is going to require hormonal control with cabergoline post-operatively, which might also aid tumor regression if there is still a small residual.

Thanks GK for posing us these teasers and looking forward to some interesting responses!

Arvind

Dr Arvind Bhateja
Consultant Neurosurgeon and Spine Surgeon,
Sita Bhateja Speciality Hospital
Bangalore 560025, INDIA

From: Dr Pramod Pillai To: neurosurgerynimhans
Sent: Tuesday, December 23, 2008 7:04:55 PM
Subject: Re: Question of the week. Gh secreting residual.
Dear All
Merry Xmas and happy new year!!!

I would still try to get his preop and follow up images, see how this tumor behaved over the last 1 year.
If this is just a residual tumor with no significant growth over the last one year, tumor control wont be my concern, instead I would try to treat him
medically with a combination of GH receptor antagonist , pegvisomant with Sandostatin or Somatuline.then follow him with serial images and GH/IGF levels.Patient' s affordability could be an issue

Otherwise , I would rather offer him radiosurgery of his parasellar tumor, it looks like there is enough space between the optic pathway the superior margin of the tumor( we need atleast 2mm distance) , but unlike the nonfunctioning tumors, functioning tumors need higher radiation dose , but there are several methods by which we can reduce dose to the optic pathway to below 8Gy.Nevertheless, there is risk to radiation injury to the cranial nerves in cavernous sinus region, but risk is definitely less than with any surgical approach .Another issue with radiosurgery is latency period , for therapeutic response, during which patient need to be on medical therapyagain. There could be small bit of tumor on the left parasellar region as well?

I wont recommend surgery for this patient , no single approach or surgery is going to cure him off his disease without cranial nerve morbidity, I am also concerned that tumor was encircling the cavernous carotid.

Pramod

From: gopalakrishnan ms
To: neurosurgery_ nimhans
Sent: Tuesday, December 23, 2008 11:53:59 AM
Subject: Re: [neurosurgery_ nimhans] Question of the week. Gh secreting residual.

Please note: The current MRI was done recently [within three months]. Preoperative GH levels were around 40 at the time of primary surgery one year back. An immediate post op MRI was not done. So this is basically a hormonally active residue. He can afford either surgery or radiosurgery (if offered at concessional rate as is done in NIMHANS) but not expensive drugs for an indefinite period.

Shall i take the liberty of adding a sub-question? :
1. What if there is no visible tumor remnant, yet the GH level is high? Is radiosurgical targetting of the entire sella an option?
Wish you Merry Christmas!
GK

From: Dr Pramod Pillai To: neurosurgery_ nimhans@yahoogro

In that case , I would go ahead with radiosurgery, hoping that it provides a hormonal remission so that he can be off the medication later on
The reported remission rate with radiosurgery is about 30-70 %.You do not have to include sella in the target in this case since there is hardly any tumor in the sella.It looks like previous surgeon had tried to preserve the normal pituitary with an intact pituitary stalk( how is his other endocrine functions?)
In rare situations, with all failed therapies with no radiological evidence of tumor in pituitary gland and if you are unable to find another source esp with Cushing's disease, sometimes pituitary gland can be targeted for radisurgery.
If you still like to do surgery on him, carefully study his vascular anatomy.With limited images you provided, I still feel there is encircling of ICA by the tumor , even there is reduced caliber of ICA on the right side. I still feel it is less likely that we can surgically cure him of the disease without causing any additional morbidity.



--- On Thu, 12/25/08,
From: brmrao1963
Subject: [neurosurgery_ nimhans] Re: Question of the week. Gh secreting residual.
To: neurosurgery_ nimhans@yahoogro ups.com
Date: Thursday, December 25, 2008, 6:14 PM
Wishing All of You a very happy and prosperous new year!
I am joining the discussion late. The patient in question has a residual secreting growth
hormone adenoma in the paracavernous area ,probably in the cavernous sinus.
Now the ideal treatment of a GH adenoma residual would be surgery-
1.endoscopic approach
2.miniorbitozygomat ic approach (interdural) .

The drawback of endoscopic approach is this tumor will require an extended endoscopic
approach .This require the surgeon to be extremely conversant with the approach-not
practical for many of us,though I personally do endoscpic pituitary surgery.
This tumor can be removed by an frontotemporal interdural approach which can be
conducted with minimal morbidity. The cranial nerves III and IV can be traced intradurally and interdurally to spare them from injury. I can speak with confidence regarding this approach as I am very familiar with the nuances of this approach.

This tumor cannot be treated with radiotherapy- period!

GKS is an option but may fail. ICA stenosis is a well known complication of GKS. With in adequate contouring cranial nerve palsies are possible!
So the 2 options are interdural approach Vs GKS. My vote is for interdural approach and this will not be overkill as high GH can kill!;patient cannot afford long-term drugs and GKS may or may-not succeed!
Cheers!
Ravi Mohan Rao

Hi all, I agree with Dr. ravi mohan Rao. this can be approached with either extended endoscopic approach or orbitozygomatic. OZ approach is really not morbid procedure as we have done for cavernous sinus tumors. I feel its morbid for the surgeon if u dont have themicro saw drill. not morbid for patient.
GK thanks for posting such cases
regards

Dr.Praveen Ganigi
Consultant Neurosurgeon & Spinal Surgeon
Narayana Institute Of Neurosciences,
Bangalore- 560099

Further update on this patient [Nov '09]
Thank you for all your suggestions...
I had taken a decision to send the patient for gammaknife radiosurgery. [Radiosurgery is not available in jipmer as of now] However, there were some apprehension of cranial nerve deficits, especially optic nerve injury - and the quantum of risks that was explained to the patient was unacceptable to him.
He underwent stereotactic radiotherapy at CMC vellore two months back. He is under follow up. Symptoms persists.
Personally I feel he will eventually require radiosurgery at a future date when the risks of cranial nerve morbidity will be even higher due to previous irradiation. (or microneurosurgery) Ill update you on his response ... though that will be many years away.