Treatment of idiopathic opsoclonus-myoclonus syndrome with intravenous immunoglobulin.

Full text

Page 1

520Neurology India December 2004 Vol 52 Issue 4
520 CMYK
Letter to Editor
Custom cranioplasty using
rapid prototyping technology
Sir,
Cranioplasty for a large skull bone defect can be a challeng-
ing surgical problem. A variety of materials have been used
for cranioplasty. Due to the advances in bioengineering, cus-
tom templates and prosthesis are now available for cranio-
plasty using Rapid Prototyping (RP) technology. Rapid
prototyping technology was originally developed to rapidly
build a prototype of a new product, especially in automobile
industry. Now the same technology is used in the medical field
in the production of anatomical models and templates, which
facilitate surgeons to optimize preoperative surgical planning,
interactive surgical simulation, while reducing operative time
and complications.
TIFAC CORE (Technology Information, Forecasting and
Assessment Council - Center of Relevance and Excellence),
PSG College of Technology, Coimbatore provided the first
custom template for cranioplasty in our patient. Under the
broad umbrella of technology vision-2020, TIFAC has set up
a center of Relevance and Excellence in product design, opti-
mization and collaborative product.1
A frontotemporal craniectomy defect in a head injury vic-
tim was closed with a prosthesis made up of a biocompatible
substance polymethyl metha acrylate (Figure 1). This pros-
thesis was a replica of the custom template produced by
Rapid Prototyping Technology, using the data of 3D-CT
scan images and 2 mm CT cuts submitted to TIFAC CORE
(Figure 2).
Rapid prototyping (RP) is a term that has been used to
describe the production of solid models from 3D computer
data by a group of relatively new technologies.2 Using an ad-
ditive approach to building shapes, RP systems join liquids,
powder or sheet materials to form physical objects layer by
layer. Rapid prototyping is now widely applied in the medical
field. Some of the classical fields for medical applications of
RP models are surgical planning and simulation, surgical re-
hearsal, training of student surgeons and radiologists, com-
munication between medical staff and patients, and design of
individual implant and prostheses. Some of the common addi-
tive Rapid prototyping technologies in medicine are Selective
Laser Sintering (SLS), Fused Deposition Modeling (FDM),
Stereolithography and recently, the most advanced Multi-jet
Modeling.3
Rapid prototyping technology has shown significant ben-
efit in Maxillo facial reconstruction, cranio synostosis, skull
and maxillo facial tumor surgery, skull plasties, orthodontic
surgery, deformities of long bone joints and knee surgery,
pelvic fractures, hip dysplasia, spinal trauma, congenital and
degenerative spinal diseases, foot and hand malformations,
and in models of soft tissue structures such as the cardio-
vascular system. The most exciting case in which RP tech-
nology was used in the recent past was in planning the suc-
cessful separation of conjoined twins (Siamese twins) by
using the RP model of the twins’ brain and their venous
structure.
J. K. B. C. Parthiban, O. Abirami*,
Arul M. Murugan*, R. Radhakrishnan*
Departments of Neurosurgery, Kovai Medical Centre Hospital,
*PSG TIFAC- CORE, PSG Industrial Institute,
PSG College of Technology, Peelamedu,
Coimbatore - 641004, India.
E-mail: juttyparthiban@hotmail.com
References
1. Abdul Kalam APJ. Evolution of technology Vision 2020, India’s core compe-
tencies. In: Abdul Kalam APJ, Rajan YS, editors. India 2020 A vision for the
new millennium 1st Ed. New Delhi: Rekha printers: 1998. p. 46-58.
2. Popat AH. Rapid prototyping and medical modeling. Niels moos, editor. Phildias
Newsletter. Denmark: 2003. p. 10-12.
3. Petzold R, Zeilhofer, Kalender WA. Rapid prototyping technology in medicine
– basics and applications. Computerzied medical imaging and graphics 1999;
23: p. 277-84.
Accepted on 10.05.2004.
Figure 1: Cranioplasty
Figure 2: Custom template and replica
Treatment of idiopathic
opsoclonus-myoclonus
syndrome with intravenous
immunoglobulin

Page 2

521Neurology India December 2004 Vol 52 Issue 4
CMYK 521
Letter to Editor
Sir,
Opsoclonus-myoclonus syndrome (OMS) is a rare but dis-
tinctive disorder, characterized by irregular, continual, and
conjugated chaotic saccades of the eyes accompanied by ap-
pendicular myoclonus and truncal ataxia. No etiological fac-
tor can be found in 50% of adult cases. In 20% of cases it
may be paraneoplastic and may also be a manifestation of
brainstem stroke or infection. The most common tumors, which
give rise to OMS are breast and lung cancers and infectious
agents are Epstein-Barr virus and enteroviruses such as
Coxackie B.1,2
A 41-year-old woman presented with severe vertigo and gait
unsteadiness for ten days. There was no history of any ante-
cedent viral infection or vaccination. Neurological examina-
tion revealed coarse eye movements with severe truncal ataxia
and limb myoclonus. Laboratory examination (routine
hematological tests, urine and cerebrospinal fluid examina-
tion, serological tests for infections, oncological bands work-
up, magnetic resonance imaging of brain and
electroencephalography) revealed no abnormality. As assays
for paraneoplastic antibodies couldn’t be performed due to
technical limitations, the patient was considered to be a case
of idiopathic OMS.
Therapeutic trial with prednisolone (1 mg/kg/orally) and
clonazepam (4 mg/day) was attempted. Because of the lack of
any beneficial effect, intravenous immunoglobulin (IVI g) (0.4
g/kg/day for five days) was added on the sixth day and Pred-
nisolone and clonazepam were tapered in the following five
days. On the third day of IVI g treatment, muscle jerking and
eye movements stabilized. She began to sit without assistance
and during the next two weeks the patient gradually recov-
ered. She was symptom free within eight weeks. Physical symp-
toms and repeated laboratory examinations for occult malig-
nancy after one-year interval was negative. She has been
asymptomatic for two years.
The response to immunotherapy is unclear in paraneoplastic
and idiopathic OMS, because the rarity of this disorder hin-
ders controlled clinical studies and the possibility of sponta-
neous remissions makes interpretation difficult in isolated
cases. In adults under 40 years of age, the clinical evolution is
more benign and the effect of IVI g seems more effective.2
IVI g is an immunmodulating agent that has multiple ac-
tivities, including neutralization of pathogenic autoantibodies,
suppression of inflammatory mediators, complement inacti-
vation, functional blockage of Fc receptors on macrophages
and modulation of T-cell functions.3 Treatment with IVI g has
been reported in a few idiopathic adult-onset OMS cases in
literature. Pless et al. first reported beneficial effects of IVI g
in 1996.4 Bataller et al analyzed 10 idiopathic and 14
paraneoplastic adult OMS patients. IVI g was used in five of
the idiopathic cases. They concluded that idiopathic OMS
presents an age dependent prognosis and immunotherapy
seems to be associated with a faster recovery.2
Our case suggests that patients with idiopathic OMS treated
with IVI g may have a faster recovery and this treatment
should be recommended in cases with severe neurological dys-
function.
Aysun Unal, M. Murat Sumer, H. Tugrul Atasoy,
Nuray Atasoy*
Departments of Neurology and *Psychiatry, Zonguldak Karaelmas
University, Faculty of Medicine, Kozlu - 67700, Zonguldak / Turkey.
E-mail: aysununal@hotmail.com
References
1.Dropcho EJ. Paraneoplastic diseases of the Nervous System. Curr Treat Op-
tions Neurol 1999;1:417-27.
2. Bataller L, Graus F, Saiz A, Vilchez JJ. Spanish opsoclonus-myoclonus Study
Group. Clinical outcome in adult onset idiopathic or paraneoplastic opsoclonus-
myoclonus. Brain 2001;124:437-43.
3. Dalakas CM. Mechanisms of action of IVIg and therapeutic considerations in
the treatment of acute and chronic demyelinating neuropathies. Neurology
2002;59:S13-21.
4.Pless M, Ronthal M. Treatment of opsoclonus-myoclonus with high-dose intra-
venous immunoglobulin. Neurology 1996;46:583-4.
Accepted on 12.04.2004.
Metastasis of frontal
oligoastrocytoma to cerebellar
vermis
Sir,
Metastasis of a low-grade glioma through the cerebrospinal
fluid (CSF) is very rare. We report a case of CSF spread of a
right frontal oligoastrocytoma to cerebellar vermis.
A 46-year-old woman presented with symptoms of raised
intracranial pressure and difficulty in walking of two months
duration. On examination, she had bilateral papilloedema and
cerebellar signs on the left side. Four years earlier she had
undergone excision of right frontal mixed oligoastrocytoma
(WHO Grade 2) followed by 54 Gy of Cobalt teletherapy to
the brain. Magnetic resonance imaging (MRI) of the brain
showed a 2 cm homogeneous contrast enhancing mass in the
inferior vermis with extension into the left cerebellar hemi-
sphere and hydrocephalus. There were postoperative changes
in the right frontal lobe in the form of loss of brain tissue and
there was no evidence of recurrence (Figures 1a and 1b). A
differential diagnosis of metastases from a systemic tumor,
CSF spread of the frontal glioma or radiotherapy-induced
tumor were considered. On referring to her previous radio-
therapy records it was found that the posterior fossa was not
included in the radiation field. Chest X-ray and an ultrasound
abdomen were normal. She underwent right
ventriculoperitoneal shunt followed by midline suboccipital