вход по аккаунту


Brainstem tumor presenting with unilateral astereognosis.

код для вставкиСкачать
Brainstem Tumor
Presenting with
Unilateral Astereognosis
Moshe Feinsod, MD, Shlomo Bentin, MSc,
Morris Moscovitch, PhD, and Uri Wald, M D
A patient with a brainstem tumor presented with astereognosis. T h e results of CT scan, evoked response
studies, and neuropsychological tests all were consistent with a noncortical origin for the sensory defect.
Feinsod M, Bentin S, Moscovitch M, et al:
Brainstem tumor presenting with unilateral
astereognosis. Ann Neurol 8:191-192, 1980
Astereognosis is regarded as a neurological disturbance of focal parietal origin. T h e r e are reports,
however, of patients in w h o m astereognosis was produced by peripheral lesions. T h e authors stress that
on the basis of clinical examination, no distinction
could be made between astereognosis of parietal
(central) or peripheral origin [l, 2 , 4-101.
A patient is presented in w h o m astereognosis was
the first manifestation of a brainstem tumor. Integration of clinical, radiological, electrophysiological, and
neuropsychological information excluded parietal
origin and established that the astereognosis was of
the peripheral type.
Case Report
A 13-year-old left-handed girl noticed on the first day at
school that her handwriting was awkward. Her gymnastic
instructor observed that her left foot was clumsy during
running. The girl did not notice any motor weakness and
was bothered only by the change in her handwriting. Examination elsewhere revealed minimal astereognosis in her
left hand. Skull roentgenograms, electroencephalogram, and
isotope brain scan were normal. A CT scan did not reveal a
tumor, and the girl was given steroids with the presumptive
diagnosis of multiple sclerosis.
The patient was seen at Hadassah University Hospital
three weeks later. Meanwhile, her handwriting had
worsened. She attributed this to the fact that the pen did
not “feel right” in her hand. No changes in mental alertness
From the Department of Neurosurgery and the Aranne Laboratory of Human Psychophysiology, Department of Neurology,
Hadassah IJniversity Hospital, Jerusalem, Israel, and the Department of Psychology, Erindale College, University of Toronto,
Mississauga, Ont, Canada.
Received Sept 18, 1979, and in revised form Jan 24, 1980. Accepted for publication Jan 27, 1980.
Address reprint requests to Moshe Feinsod, MD, Department of
Neurosurgery, Hadassah University Hospital, Ein-Kerem,
Jerusalem, Israel.
or physical performance were noted. Physical examination
did not reveal any abnormal finding. On neurological examination she was found to be alert, intelligent, and
cooperative. There was minimal left facial weakness of
central type and a left upgoing toe. N o cerebellar signs
could be elicited. No abnormalities of the senses of touch,
temperature, position, and vibration were found on repeated examinations. Stereognosis and object recognition
were disturbed in the left hand but were normal in the right
hand. The visually evoked response recorded from over
the right and left occipital poles was of normal configuration and latency.
CT scan demonstrated a brainstem tumor. The girl was
reexamined four weeks later. Her handwriting had continued to deteriorate, and stereognosis and object recognition in the left hand were profoundly disturbed. The patient took longer to answer positioning on the left than on
the right. The rest of the neurological examination was unchanged. The CT scan suggested some enlargement of the
tumor. A pneumoencephalogram (Fig 1) confirmed its intraaxial location.
The somatosensory evoked rcsponse to right and left
median nerve stimulation was recorded from over the
somatosensory cortex. When the right hand was stimulated, normal responses were recorded from over each
hemisphere. Stimulation of the left median nerve evoked a
very low amplitude response in which the early components could not be identified. No difference was seen in the
response recorded from the contralateral and ipsilateral
hemispheres (Fig 2).
Because astereognosis was such a prominent feature in
the patient’s symptomatology, we evaluated high-order
parietal function. The following tests were applied in order
to reveal any disturbance of personal or extrapersonal spatial orientation: (1) Butters’ stick test for spatial orientation, ( 2 ) body recognition test, ( 3 ) left-right naming test,
( 4 ) WISC maze test, ( 5 ) facial recognition test, and (6)
three-dimensional constructive apraxia test. In each of
these tests, the patient’s score was normal or above the
mean for her age.
Exploration of the posterior fossa was carried out. The
floor of the fourth ventricle was found elevated by an intramedullary mass. No extraaxial protrusion of tumor was
seen, and a biopsy was not taken. Radiotherapy (5,000
rads) was started. There was no substantial change in the
patient’s neurological condition during nine months of
follow-up. The electrophysiological and neuropsychological tests were repeated with the same results.
Astereognosis not associated with a decrease in any
modality of superficial sensibility d u e to a lesion at a
lower level than the parietal lobe was probably first
reported by Batten in 1912 [l]. His patient had a
high cervical lesion. Gans [ 4 ] and Nissl von Mayendorf [71 followed with similar cases. Cushing [21 in
1923 described a patient in whom the finding of unilateral astereognosis led to negative exploration of
the parietal region. He was later found to have a
tried to distinguish
posterior fossa tumor. Schott
0364-5134/80/080191-02$01.25 @ 1979 by Moshe Feinsod
Fig I . Pneumoencephalogram showing thej4oor of the fourth
ventricle elevated by a brainstem mass (arrow) (midline tomogram).
underwent unilateral mastectomy and irradiation for
breast cancer. They developed astereognosis in the
homolateral hand. This led Halpern to stress the
need for clinical means to differentiate between astereognosis and stereoanesthesia.
The tests carried out in our patient made this distinction possible. With the introduction of noninvasive techniques like computerized tomography, the
diagnosis of space-occupying lesions is made much
earlier than was possible several years ago. The brainstem tumor in our patient was discovered when astereognosis was the sole symptom. The battery of
neuropsychological tests provided direct evidence
for integrity of parietal lobe function. The somatosensory evoked response to stimulation of the left
hand pointed to a conduction defect because the
early components were missing and there was no
difference between the responses of the two hernispheres (see Fig 2). At the same time, normal responses were recorded from over each hemisphere
when the right hand was stimulated, suggesting intact
hemispheric function. The normal visual evoked response, especially in its late components [ 3 ] , served
as further evidence for normal parietal lobe function
and excluded the first diagnosis of multiple sclerosis.
F i g 2 . The somatosensory evoked response to stimulation of the
right (RMN)and left (LMN) median nerve. Only recordings from over the contralateral hemispheres are displayed.
(LH = left hemisphere; RH = right hemisphere.)
between astereognosis of cortical and subcortical lesions but was unable to differentiate between the two
on the basis of clinical examination. Rubinstein [9] in
1938 described two patients with astereognosis due
to extraaxial tumors in the region of the foramen
magnum. He carefully reviewed the literature and
the findings in his patients but could not offer a
means to distinguish between astereognosis and
stereoanesthesia. These terms were suggested by
Riley [ B ] , but he could not devise any clinical test to
distinguish between them.
In their three patients with astereognosis due to
midcervical (C4-5) tumors, Halpern and Beller [61
demonstrated how a lesion located in the spinal cord
could cause astereognosis identical to that of parietal
origin. Halpern [ 5 ] later reported three women who
192 Annals of Neurology Vol 8 No 2 August 1980
1. Batten FE: Case of astereognosis probably due to a lesion of
the posterior columns in the cervical region. Proc R Soc Med
[Neuroll 5:150-153, 1912
2. Cushing H: Notes on a series of intracranial tumors and conditions simulating them. Arch Neurol Psychiatry 10:605-668,
3. Feinsod M, Hoyt WF, Wilson WB: Suprastriate hemianopia.
Lancet 1:1225-1226, 1974
4. Gans A: Ueber Tastblindheit und ueber Stoerungen der
raemlichen Wahrnehmung der Sensibilitaet. 2 Neurol
Psychiatr 31303-428, 1918
5. Halpern L: Astereognosis not of cortical origin. J Neurol Sci
7:245-250, 1968
6. Halpern L, Beller AJ: Ueber das Vorkommen von primken
Astereognosien bei Gsionen Zervikalsmarks. Schweiz Arch
Neurol Psychiatr 4:lOO-108, 1953
7. Nissl von Mayendorf E: Tastblindheit nach Schussverletzung
der hinten Wurzeln. 2 Neurol Psychiatr 39:282-292, 1919
8. Riley HA: Discussion of Weinstein EA, Wechsler IS: Dermoid tumor in the foramen magnum with astereognosis and
dissociated sensory loss. Arch Neurol Psychiatry 44: 162-174,
9. Rubinstein JE: Astereognosis associated with tumors in the
region of the foramen magnum. Arch Neurol Psychiatry
3911016-1032, 1938
10. Schott E: Uber die Verwandbarkeit der Symptoms der
Stereoagnosie in der topischen Diagnostik. Dtsche 2 Nervenheilkd 80:357-372, 1924
Без категории
Размер файла
220 Кб
astereognosis, brainstem, presenting, unilateral, tumors
Пожаловаться на содержимое документа