Schizencephaly: Antenatal detection using ultrasound

Clinical

Radiology

( 1999) 54, 620-621

Case Reports Schizencephaly:

Antenatal Detection Using Ultrasound

A. F. A. CECCHERINI*,

P. TWINING*,

S. VARIENDt

*Department of Radiology, QMC Nottingham, and fDepartment of Pathology, Shefield Children ‘s Hospital, NHS Trust, Sheffield, U.K.

Schizencephaly is an unusual condition rarely detected antenatally. It is a neuronal migrational disorder consisting of clefts in the brain that communicate with the lateral ventricles. We report a case of schizencephaly detected during a routine antenatal ultrasound scan in the second trimester.

CASE REPORT A healthy 22 year old multigravida attended outpatients at 18 weeks gestation for a routine antenatal booking ultrasound examination. She had given birth to a term, healthy male 2 years previously and had had a spontaneous abortion at 4 weeks gestation I year earlier. At this time, hydrocephalus was noted, and the patient was referred to a Consultant Radiologist for a detailed ultrasound. This showed bilateral asymmetric cortical clefts (larger on the right) communicating with the lateral ventricles in the temporo-parietal regions with associated asymmetrical ventriculomegaly. The left ventricular diameter was IOmm and the right I3 mm. The third ventricle and posterior fossa structures were normal (Fig. 1). The remainder of the fetus and liquor volume was normal. The bi-parietal diameter and head circumference dated the pregnancy between 21 and 22 weeks. The diagnosis of schizencephaly was made at this time. Fetal karyotype was normal and infection screening negative. A decision to proceed with a termination of pregnancy was taken by the mother and labour was induced by a prostaglandin pessary. A female fetus was delivered. At autopsy. bilateral ventricular dilatation was noted with large irregular temporo-parietal cavitations (approximately I.5 x 1.2cm) communicating with the ventricles and covered by leptomeningeal tissue. No other abnormality was noted (Fig. 2). On histological examination of the brain, the ependyma of the lateral ventricles had been shed and replaced by gliosis, calcification and haemosiderin laden macrophages with foci of old and recent haemonhage in the germinal matrix. Patches of neuroblastic migrational arrest was seen in the vicinity of the defect.

DISCUSSION Schizencephaly is a neuronal migrational abnormality in which a pia-covered grey matter-lined cleft extends from the ventricular surface to the superficial grey matter. The clefts are

Correspondence Queens Medical

to: Dr A. F. A. Ceccherini. Department Centre, Nottingham. NC7 2UH.

0009-9260/99/090620+08

$12.00/O

of Radiology,

often bilateral and symmetrical in the parasylvian region. The lips of the cleft are either open to some degree, separated by CSF, or closed. There is some controversy regarding the cause of this abnormality. While some authors advocate a vascular insult [ 1,2] with a secondary effect on brain development, others suggest a primary cerebral dysgenesis [3,4]. Schizencephaly is rarely detected in utero, there are six published case reports of antenatal detection. One study [I] noted schizencephaly antenatally at 31 weeks gestation. A follow-up study at 36 weeks showed further progression of the lesion. The abnormalities occurred in the middle cerebral artery territory. The authors suggested this pattern of abnormalities and progression favoured a vascular insult at the likely aetiology, rather than a primary cerebral dysgenesis. Suchet [2] reviewed three cases of antenatally detected schizencephaly on whom serial doppler ultrasonography was performed. Two fetuses had been exposed to cocaine in the first trimester, and an association between cocaine induced vasospasm and schizencephaly was suggested. In the third reported case there was persistent occlusion of the right middle cerebral artery supporting the author’s view of a vascular lesion causing schizencephaly. The earliest detective case of schizencephaly was at 22 weeks of gestation. Conversely, another author [5] favoured a primary developmental abnormality to account for the combination of schizencephaly and absence of the cavum septum pellucidurn noted on an antenatal scan at 38 weeks gestation. Those who favour a primary cerebral dysgenesis place the development of defects in the first 2 months of gestation [3,5]. One author [7] suggests that the clefts arise in the third month of gestation, after other fetal organs have already formed. Our case was detected at an earlier stage of gestation than the previously cited case reports. The features noted, clefts in the middle cerebral artery territory, lack of associated abnormalities and presentation in the second trimester, could be compatible with either of the hypotheses stated previously. The importance of making an accurate antenatal diagnosis is that the outcome for schizencephaly is considerably poorer than for other causes of ventriculomegaly. Typical symptoms 0

1999 The

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CASE REPORTS

Fig. 2 - Post-mortem specimens. (N) Brain as seen from above demonstmting bilateral clefts. (!I) Brain seen from the right side showing deep cleft in temporo-paneral region.

include seizures. mental retardation, spastic tetraplegia and blindness [S]. This has great significance when counselling a patient as to the likely prognosis. It is likely that earlier detection and serial antenatal ultrasound will shed light on the aetiology and progression of schizencephaly. At present, there are conflicting theories, but as with many conditions with a spectrum of abnormalities, multiple aetiological factors are likely to play a part. Acknowledgements. We would like to thank Mr. F. A. Howard, Consultant Obstetrician and Gynaecologist. Doncaster Royal Infirmary for inclusion of his patient in this case report.

REFERENCES

(c) Fi .g. I - Antenatal ultrasound tindings ((1) Image through fetal head demonstrating right-sided cleft (arrow) communicating with liltera ventriclc. (/I) Image showing right-sided cleft with small island of cerebral cortex (xrow). (c) Image showing left-aided cleft.

1 Klingensmith W, Cioffi-Rsgan DT. Schizencephaly: diagnosis and progression in utero. Radiology 1986: I SY(3):6 17-6 IS. 2 Suchet IB. Schizencephaly: antenatal and post natal assessment with colour How Doppler imaging. Curzodirrr~ Associoriorr of‘ Rdiologis~s

Jolrrrra/

1994:45(3):193-200.

3 Ynkovlev PI, Wadsworth RC. Schizencephaly: a study of the congenital clefts in the cerebral mantle. Clefts with hydrocephalus and lips separated. J Nrrrro/x~~lwl Ex/J Nerr,o/s I Y46:5: 169-206.

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CLINICAL

4 Page LK, Brown SB, Gargano FP. el nl. Schizencephaly: a clinical study for review. Child Brain 1975; 1:348-358. 5 McGahan JP, Ellis W, Lindford KK, ef ol. Congenital cerebrospinal fluid containing intracranial abnormalities: a sonogmphic classification. J C/in U/r,nsowd 1988;16(8):53 l-544. 6 Williams JP, Blalock CP, Dunaway CL et nl. Schizencephaly. J Conrprrr Assisr Tomogr 1983;7: 135- 139.

RADIOLOGY 7 Dekaban A. Large defects in cerebral hemispheres associated with cortical dyspenesis. J Ne~rropnrhol Exp Nr~rrol 1965;24:512-530. 8 Folilie A, Constantine G. The central nervous system. In: Dewbury K. Meire H. Cosgrove D. Ufrosorrnd in Ohsrrrr-its nrtd Gyoecolugy. 1st ed. Churchill Livingstone 1993:271-315.

MRI Findings of Cerebral Paragonimiasis in Chronic Stage M. NOMURA,

H. NITTA,

Departttzet~t of Nettrosurgety,

M. NAKADA, Kanazawa

University

Cerebral paragonimiasis is a parasitic infectious disease. Many cases have been reported, and plain X-rays and computed tomography (CT) findings of cerebral paragonimiasis in both the acute and chronic stages have been described [l-3]. Recently, cerebral paragonimiasis has become an uncommon disease in developed countries, however, such a lesion in the chronic stage may be misdiagnosed as a primary intracranial tumor with calcification. Although magnetic resonance imaging (MRI) has become an important diagnostic tool in intracranial lesions, only one case of chronic cerebral paragonimiasis has described MRI findings [4]. In this paper. we describe the MRI findings of chronic cerebral paragonimiasis.

CASE

T. YAMASHIMA.

J. YAMASHITA

School of Medicine,

Kattazawa. Japan

the adjacent brain tissue. The content of the main mass on MRI was a highly viscous and yellowish fluid. Pethological examination showed many Pnrogouimrs ova along the inner surface of capsule (Fig. 3). Her post-operative course was uneventful.

DISCUSSION

Paragonimiasis is a parasitic disease endemic to the Far East and Southeast Asia. Most infections in humans are caused by ingestion of undercooked fresh water crabs or crayfish contaminated with Westermani flukes. Although the lung is the

REPORT

A 66.year-old woman was admitted with a 7-year history of hallucination. She had been raised on the Noto Peninsula, Ishikawa Prefecture. Japan. where pxagonimiasis used to be endemic. She had eaten cooked freshwater crabs during her childhood and adolescence. On admission. no neurological abnormality was found except for visual disturbance on the right eye due to glaucoma. Plain skull X-rays showed multiple calcifications in the right frontotemporal region. Computed tomography revealed multiple calcified masses of various sizes and shapes in the right frontal and temporal lobes (Fig. I). Atrophic changes and widening of the cortical sulci of the right frontal and temporal lobes were apparent on both Tl- and U-weighted images (Fig. 20). Magnetic resonance imaging revealed that the main mass in the temporal lobe was composed of an upper and a lower part. The lower part of the mass showed a low intensity on both Tl- and T2-weighted images, while the upper part had a slightly low intensity on Tl-. and peripheral low and central high intensity on T2-weighted images (Fig. 2/~, d). Gd-DTPAenhanced MRI showed peripheral enhancement in the upper part of the mass (Fig. 2~). This enhanced region was seen as a low intensity area on TZ-weighted images (Fig. 2d). Our preoperative diagnosis included a brain tumour with calcification such as meningioma or oligodendroglioma. or parasitic disease such as paragonimiasis. CaIcified masses of various sizes were removed through a right frontotemporal craniotomy. The surface of the masses were smooth and yellowish. These masses were well demarcated and could be easily separated from Correspondence to: Dr M. Nomura, zawa University School of Medicine, 8641, Japan.

Department of Neurosurgery. Kana13-l Takaramachi, Kanazawa 920.

Fig. I - Axial CT showing fronto-temporal region.

several round and oval calcifications

in the right