Letter to Editor

In MS patients with INO, hyperintense lesions in MLF have been demonstrated in all patients on PD sequence, in 88% on T2-weighted imaging and in 44% on FLAIR sequences.4 In our patients the lesion in the MLF was detected only on PD coronal and FLAIR. Thus our recommendation in patients is to acquire PD sequence in addition to the other sequences in a patient with suspected INO.

S. Kumar, S. Aaron Unit, Department of Neurological Sciences, Christian Medical College, Vellore - 632004, Tamil Nadu, India. E-mail: [email protected]

References

Figure 1: Proton density (PD)- coronal sequence MR imaging of brain 1. Tintore M, Rovira A, Rio J, Nos C, Grive E, Sastre-Garriga J, et al. New showing a focal hyperintense lesion in midbrain tegmentum on the diagnostic criteria for : application in first demyelinating epi- right side, in the region of trochlear nucleus sode. Neurology 2003;60:27-30. 2. Lee AG, Tang RA, Wong GG, Schiffman JS, Singh S. Isolated inferior rectus muscle palsy resulting from a nuclear third nerve lesion as the initial manifes- tation of multiple sclerosis. J Neuroophthalmol 2000;20:246-7. 3. Frohman TC, Frohman EM, O’Suilleabhain P, Salter A, Dewey RB Jr, Hogan N, et al. Accuracy of clinical detection of INO in MS: Corroboration with quan- titative infrared oculography. Neurology 2003;61:848-50. 4. Frohman EM, Zhang H, Kramer PD, Fleckenstein J, Hawker K, Racke MK, et al. MRI characteristics of the MLF in MS patients with chronic internuclear ophthalmoparesis. Neurology 2001;57:762-8. 5. Leigh RJ, Zee DS. Diagnosis of central disorders of ocular motility: The Neu- rology of Eye movements. 3rd Ed. New York: Oxford, Oxford University Press; 1999. p. 502-9. 6. McDonald WI, Compston A, Edan G, et al. Recommended diagnostic criteria for multiple sclerosis: Guidelines from the International Panel on the diagnosis of multiple sclerosis. Ann Neurol 2001;50:121-7. 7. Atlas SW, Grossman RI, Savino PJ, Schatz NJ, Sergott RC, Bosley TM, et al. Internuclear ophthalmoplegia: MR-anatomic correlation. AJNR Am J Neuroradiol 1987;8:243-7.

Accepted on 16.06.2004.

Figure 2: Fluid-attenuated inversion recovery (FLAIR)- sagittal sequence MR imaging of the brain showing a focal hyperintense lesion in midbrain tegmentum Heterogeneity in clinical infections including neurosyphilis, Arnold- presentation of acute Chiari malformation with associated syringobulbia, Wernicke’s , and .5 In our patient disseminated all the other possibilities other than demyelinating pathology were excluded. She did not have any prodromal illness or vac- cination before the onset of the illness and no other white matter MRI lesions. We feel that our patient is probably a Sir, case of primary , possible MS. The newly Acute disseminated encephalomyelitis (ADEM) refers to a revised MRI diagnostic criteria for MS allow the diagnosis to monophasic, immune-mediated, inflammatory demyelinating be made after one attack, if stringent MRI criteria are met. It disease of the central nervous system, predominantly affect- has been emphasized that in patients with first attack of de- ing the white matter. Though ADEM was first reported more myelinating disease, a diagnosis should be withheld unless new than 70 years ago1 and the term is widely used today, it seems symptoms and signs or imaging abnormalities appear, more to be inadequate in the light of increasing clinical experience than 3 months after the onset of clinical symptoms.6 with ADEM. The current communication is aimed at high- Clinical examination fails to detect INO in 71% and 25% of lighting the clinical heterogeneity of ADEM and the need for the cases with mild and moderate INO respectively, and de- a more suitable term for this syndrome. tection is improved by quantitative infrared oculography.3 MRI The term “disseminated” refers to the involvement of mul- is the imaging modality of choice to detect the lesions of MLF.7 tiple sites of neuraxis, either clinically or subclinically (when

518 Neurology India December 2004 Vol 52 Issue 4 518 CMYK Letter to Editor identified with the help of neuroimaging or multi-mode evoked hemorrhages and TIAs, thrombolysis was not done due fac- potential studies in the absence of symptoms/signs). However, tors beyond cost and time. In our study,2 of twenty patients “focal or site-restricted forms” of ADEM are well known. Cases presenting within three hours, nine (45%) patients presented presenting with optic neuritis or alone have been re- within one hour, two (10%) within 1-2 hours and nine (45%) ported.2 Solitary hemispheric lesions mimicking tumors have between 2-3 hours of the onset of the . Of them, thir- also been reported.3 Therefore, the term “disseminated” is teen (65%) were ischemic and though seven being not appropriate for all cases of ADEM. eligible, none received thrombolysis. We found it interesting The term “encephalomyelitis” is non-specific as it means that none of the patients were explained the available option of the brain and indicating that the of thrombolytic therapy and the cost involved. This to some entire central nervous system is involved. However, many cases extent, could be due to reluctance on part of the physicians of ADEM do not have such a diffuse involvement and mani- to provide thrombolysis to stroke patients though we did not fest with lesser degrees of involvement. use a questionnaire to analyze the physician factors. It ap- The term ADEM (a post-infectious or post-vaccinial illness) pears that the poor rate of thrombolytic therapy in our coun- does not indicate the etiology and therefore does not help in try cannot be entirely blamed on the part of patients for the differentiation of infectious (viral) or allergic encephalo- their late presentation and non-affordability of rTPA. The myelitis. In addition, it does not convey the fact that ADEM onset of stroke is such a catastrophic event in majority of is a monophasic illness (as against multiple sclerosis which is cases, with paralysis of limbs, inability to speak or loss of con- recurrent in nature). scious, that it will create a panic to the patients and their These observations point to the fact that ADEM is a term relatives, and they will be immediately rushed to the nearest that is not appropriate for many patients diagnosed with it. available health facility. Hence, in an urban or more impor- There is a need to substitute it with a better term. “Monopha- tantly in a rural setup, the primary care physician must ex- sic immune-mediated central nervous system demyelination” plain to the patient’s relatives, the available treatment op- is one suggestion from us. tions, costs involved and the importance of time window, and refer them to an appropriate referral center which provides S. Kumar, M. Alexander, C. Gnanamuthu thrombolytic therapy. Even for the patients from rural areas, Neurology Unit, Department of Neurological Sciences, Christian despite lack of adequate public transport facilities and ambu- Medical College, Vellore, Tamil Nadu - 632004, India. lance services, a sizable number reached the referral center E-mail: [email protected] with the help of private transportation, which is reflected by as many as 20 (31%) of 64 rural patients reaching within 3 References hours. Training programmes in the form of workshops and CME programmes need to be provided for the primary care 1. McAlpine D. Acute disseminated encephalomyelitis: Its sequelae and its rela- tionship to disseminated sclerosis. Lancet 1931;846-52. physicians involved in the care of stroke patients, to encour- 2. Murthy JM. Acute disseminated encephalomyelitis. Neurol India 2002;50:238- age them to initiate thrombolysis in more number of strokes. 43. 3. Singh S, Alexander M, Sase N, Korah IP. Solitary hemispheric demyelination The role of physicians is of paramount importance, in render- in acute disseminated encephalomyelitis: Clinicoradiological correlation. ing thrombolytic therapy, in this new era of economic develop- Australas Radiol 2003;47:29-36. ment, where more number of patients are able to reach the Accepted on 11.06.2004. hospital within the time window and are able to afford the drug.

Kaveer Nandigam, Sunil K. Narayan Time and cost: Are they the Department of Neurology, 428, Lister House, Jawaharlal Institute of Post Graduate Medical Education and Research, Pondicherry, only contributors to poor rate India. E-mail: [email protected] of stroke thrombolysis References

Sir, 1. Pandian JD. Feasibility of acute thrombolytic therapy for stroke: Comments.Neurol India 2004;52:126-7. 1 The study published by Dr. Pandian in an urban indus- 2. Nandigam K, Narayan SK, Elangovan S, Dutta TK, Sethuraman KR, Das trial city like Ludhiana, showed that only 7% of patients AK. Feasibility of acute thrombolytic therapy for stroke. Neurol India 2003;51:470-3. reaching within 3 hours received rTPA after complete evalu- ation and thrombolysis couldn’t be given in 10% of the sub- Accepted on 25.05.2004. jects due to non-affordability of the drug, which shows that in rest of about 35% of ischemic stroke patients, excluding

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