Agenesis of Corpus Callosum and Intraventricular Lipomas
lateral ventricle (Fig 1B). The corpus callosum was absent, as observed by the radial arrangement of the medial brain sulci on US (Fig IA) and MRI and by widely spaced frontal horns observed with US, CT, and MRI (Figs lB.2.3). Cranial CT (Fig 2) and MRI (Fig 3) demonstrated fat in the interhemispheric mass and intraventricular masses; calcification at the periphery of interhemispheric lipoma was visualized only on CT (Fig 2). She was examined subsequently for 10 months at the outpatient clinic and exhibited no evidence of developmental delay or neurologic deficit and did not manifest seizures.
Discussion
Aruna Vade, MD and Sandra W. Horowitz, MD
Intracranial lipomas are rare and usually do not have clinical expression. They are located most commonly in the interhemispheric fissure and may also he found in the quadrigeminal, ambient, chiasmatic, interpeduncular, sylvian, and perimesencephalic cisterns. Interhemispheric lipomas may be associated with choroid plexus lipomas. The ultrasonography, computed tomography, and magnetic resonance imaging findings are reported in a neonate with lateral ventricular choroid plexus lipomas and interhemispheric lipoma associated with agenesis of the corpus callosum. Vade A, Horowitz SW. Agenesis of corpus callosum and intraventricular lipomas. Pediatr Neural 1992;8:307-9.
Introduction Choroid plexus lipoma is a rare developmental anomaly. To our knowledge, this is the first neonate reported with intraventricular lipomas in whom ultrasonography (US), computed tomography (CT), and magnetic resonance imaging.(MRI) findings are compared. Clinical awareness of this condition is important for proper management. Case Report This white female was born by cesarean section, at 35 weeks gestation, to a 3 l-year-old white mother (G4,P3) with a history of prolonged rupture of membranes. An obstetric US at an outside hospital reportedly had demonstrated intracranial calcifications in the fetus. At birth, Apgar score was 8, weight 2,520 gm, head circumference 31.5 cm, anterior fontanel was soft, and neurologic examination was normal. She had no seizures and electroencephalography (EEG) was not performed. The mother’s TORCH titers were negative. Cranial US revealed a bulky echogenic mass in the interhemispheric fissure (Figs IA,lB) extending through the choroidal fissure into each
From the Department of Radiology; 2160 South First Avenue; Maywood,
Loyola University IL 60153.
Medical
Center;
Rokitansky initially reported lipoma of the corpus callosum or interhemispheric lipoma in 1856 [cited in l-31. Formerly believed to be rare tumors, these lipomas have been identified as incidental findings with greater frequency since the advent of CT and MRI [1,3]. The reported incidence of their association with intraventricular choroid lipomas is variable (15-72%) [ 1,2]. Sauerbrei and Cooperberg initially described the US appearance of an interhemispheric lipoma [cited in 41. Mulligan and Meier reported the US findings of interhemispheric lipoma associated with choroid plexus lipomas in 2 intrauterine fetuses [4]. Intracranial lipomas occur almost exclusively in the cisterns [l-3]. Embryologically, the potential subarachnoid cisterns are filled with primitive meningeal tissue which ultimately resorbs leaving behind subarachnoid cisterns. When primitive meningeal tissue is not resorbed completely, it then differentiates into the adipose line and results in mature lipoma [ 1,2]. Embryologically, the choroid fissure develops as an invagination of the interhemispheric cistern and therefore primitive meningeal tissue is also present in the lateral ventricles adjacent to the choroid plexus [1,2]. Lipomatous differentiation of primitive meningeal tissue in the lateral ventricles causes choroidal lipomas [ 1,2]; therefore, choroid plexus lipomas occur in association with interhemispheric lipomas. Normal vessels and nerves course through these lipomas and can be observed with Doppler US as pulsatile structures [4] and with MRI as flow-void structures [3]. Choroid vessels through the lipoma are not observed because they are very small [3]. Perilesional and lesional calcifications may be present with interhemispheric and choroidal lipomas and are best visualized with CT. Calcification occurs adjacent to the interhemispheric lipoma possibly due to pressure necrosis of adjacent brain parenchyma [3]. Coronal US and MRI can best delineate the extension of pericallosal lipoma into the lateral ventricles through the choroid fissure. Partial or complete agenesis of the corpus callosum is present in 50% of patients with interhemispheric lipomas [ 11. The lipoma probably causes mechanical obstruction to
Communications should be addressed to: Dr. Vade; Department of Radiology; Loyola University Medical Center, 2160 South First Avenue; Maywood, IL 60153. Received December 30. 1991; accepted April 13, 1992.
Vade and Horowitz:
IntraventricuIar
Lipomas
307
Figure I. (A) Midline sagittal and (B) coronal cranial US. (A) Revealing a bulky echogenie mass in the biterl~emispheric fissure (straight white arrow) and (B) extending through (A) The the choroidaljissure (curved orrows) and into each lateral ventricle (open arrows). radial arrangement of medial brain sulci (smull straight arrows) and (B) widely spaced frontal horns are consistent with agenesis of the corpus callosum.
the rostral growth of the corpus callosum. Yock reported that agenesis of the corpus callosum was necessary in all interhemispheric lipomas associated with choroid plexus lipomas [5]. Isolated intracranial lipomas may be asymptomatic; however, agenesis of the corpus callosum may be associated with other congenital brain anomalies, such as gyral dysplasias and heterotopia which are best evaluated by MRI [2]. Fifty percent of the infants with pericallosal lipoma may present with seizures, hemiparesis, vomiting, or mental retardation [5]. Treatment is generally sympto-
308 PEDIATRIC NEUROLOGY
Vol.8 No.4
matic because surgical removal yields poor results with almost 50% mortality in the immediate postoperative period [5]. Total removal of tumor is impossible because of vascular inclusion [6]. US findings of echogenic masses in the lateral ventricles in an asymptomatic neonate should suggest intraventricular lipomas and MRI should be performed to eliminate other associated brain malformations that may coexist and affect the prognosis in the neonate. Subsequent evaluation with CT or MRI may be required when there is an alteration in the clinical status.
Figure 3. Coronal cranial T/-weighted MRI reveals high SI lesions ia the frontal horns (curved arrows) and interhemispheric f&ares (.wai,ghr arrow) coasisrerrt rvirh fat. Low SI area (open arrows) swrorrndiag irlre~llertlisplreric lipoma is due fo chenkal shiJ artifkt.
References [l]
Buxi
TBS.
Mathur
RK.
Doda
SS. Computed
tomography
of
lipoma of corpus callosum and choroid plexus lipoma: Report of two cases. .I Comput Tomogr 1987; I 157-60. [2] lhwit CL, Barkovich AJ. Pathogenesis of intracranial lipoma: An MR study in 42 patients. AJNR 1990; 11:665-74. [3] ‘lhwit CL, Williams RG, Armstrong EA, Marlin AE. MR imaging
[S] Yock DH Jr. Choroid plexus lipomas associated with lipoma of the corpus callosum. J Comput Assist Tomogr 1980;4:678-82. [6] List CF, Holt JF, Everett M. Lipoma of the corpus callosum. A clinicopathological study. Am J Roentgen01 Radium Ther Nucl Med 194658:
125-34.
plexus lipomas. AJNR 1990: Il:2024. G. Meier P. Lipoma and agenesis of the corpus callosum with associated choroid plexus lipomas in utero diagnosis. J Ultrasound Med 1989;8:583-8.
[4]
of choroid
Mulligan
Vade and Horowitz:
Intraventricular
Lipomas
309
lateral ventricle (Fig 1B). The corpus callosum was absent, as observed by the radial arrangement of the medial brain sulci on US (Fig IA) and MRI and by widely spaced frontal horns observed with US, CT, and MRI (Figs lB.2.3). Cranial CT (Fig 2) and MRI (Fig 3) demonstrated fat in the interhemispheric mass and intraventricular masses; calcification at the periphery of interhemispheric lipoma was visualized only on CT (Fig 2). She was examined subsequently for 10 months at the outpatient clinic and exhibited no evidence of developmental delay or neurologic deficit and did not manifest seizures.
Discussion
Aruna Vade, MD and Sandra W. Horowitz, MD
Intracranial lipomas are rare and usually do not have clinical expression. They are located most commonly in the interhemispheric fissure and may also he found in the quadrigeminal, ambient, chiasmatic, interpeduncular, sylvian, and perimesencephalic cisterns. Interhemispheric lipomas may be associated with choroid plexus lipomas. The ultrasonography, computed tomography, and magnetic resonance imaging findings are reported in a neonate with lateral ventricular choroid plexus lipomas and interhemispheric lipoma associated with agenesis of the corpus callosum. Vade A, Horowitz SW. Agenesis of corpus callosum and intraventricular lipomas. Pediatr Neural 1992;8:307-9.
Introduction Choroid plexus lipoma is a rare developmental anomaly. To our knowledge, this is the first neonate reported with intraventricular lipomas in whom ultrasonography (US), computed tomography (CT), and magnetic resonance imaging.(MRI) findings are compared. Clinical awareness of this condition is important for proper management. Case Report This white female was born by cesarean section, at 35 weeks gestation, to a 3 l-year-old white mother (G4,P3) with a history of prolonged rupture of membranes. An obstetric US at an outside hospital reportedly had demonstrated intracranial calcifications in the fetus. At birth, Apgar score was 8, weight 2,520 gm, head circumference 31.5 cm, anterior fontanel was soft, and neurologic examination was normal. She had no seizures and electroencephalography (EEG) was not performed. The mother’s TORCH titers were negative. Cranial US revealed a bulky echogenic mass in the interhemispheric fissure (Figs IA,lB) extending through the choroidal fissure into each
From the Department of Radiology; 2160 South First Avenue; Maywood,
Loyola University IL 60153.
Medical
Center;
Rokitansky initially reported lipoma of the corpus callosum or interhemispheric lipoma in 1856 [cited in l-31. Formerly believed to be rare tumors, these lipomas have been identified as incidental findings with greater frequency since the advent of CT and MRI [1,3]. The reported incidence of their association with intraventricular choroid lipomas is variable (15-72%) [ 1,2]. Sauerbrei and Cooperberg initially described the US appearance of an interhemispheric lipoma [cited in 41. Mulligan and Meier reported the US findings of interhemispheric lipoma associated with choroid plexus lipomas in 2 intrauterine fetuses [4]. Intracranial lipomas occur almost exclusively in the cisterns [l-3]. Embryologically, the potential subarachnoid cisterns are filled with primitive meningeal tissue which ultimately resorbs leaving behind subarachnoid cisterns. When primitive meningeal tissue is not resorbed completely, it then differentiates into the adipose line and results in mature lipoma [ 1,2]. Embryologically, the choroid fissure develops as an invagination of the interhemispheric cistern and therefore primitive meningeal tissue is also present in the lateral ventricles adjacent to the choroid plexus [1,2]. Lipomatous differentiation of primitive meningeal tissue in the lateral ventricles causes choroidal lipomas [ 1,2]; therefore, choroid plexus lipomas occur in association with interhemispheric lipomas. Normal vessels and nerves course through these lipomas and can be observed with Doppler US as pulsatile structures [4] and with MRI as flow-void structures [3]. Choroid vessels through the lipoma are not observed because they are very small [3]. Perilesional and lesional calcifications may be present with interhemispheric and choroidal lipomas and are best visualized with CT. Calcification occurs adjacent to the interhemispheric lipoma possibly due to pressure necrosis of adjacent brain parenchyma [3]. Coronal US and MRI can best delineate the extension of pericallosal lipoma into the lateral ventricles through the choroid fissure. Partial or complete agenesis of the corpus callosum is present in 50% of patients with interhemispheric lipomas [ 11. The lipoma probably causes mechanical obstruction to
Communications should be addressed to: Dr. Vade; Department of Radiology; Loyola University Medical Center, 2160 South First Avenue; Maywood, IL 60153. Received December 30. 1991; accepted April 13, 1992.
Vade and Horowitz:
IntraventricuIar
Lipomas
307
Figure I. (A) Midline sagittal and (B) coronal cranial US. (A) Revealing a bulky echogenie mass in the biterl~emispheric fissure (straight white arrow) and (B) extending through (A) The the choroidaljissure (curved orrows) and into each lateral ventricle (open arrows). radial arrangement of medial brain sulci (smull straight arrows) and (B) widely spaced frontal horns are consistent with agenesis of the corpus callosum.
the rostral growth of the corpus callosum. Yock reported that agenesis of the corpus callosum was necessary in all interhemispheric lipomas associated with choroid plexus lipomas [5]. Isolated intracranial lipomas may be asymptomatic; however, agenesis of the corpus callosum may be associated with other congenital brain anomalies, such as gyral dysplasias and heterotopia which are best evaluated by MRI [2]. Fifty percent of the infants with pericallosal lipoma may present with seizures, hemiparesis, vomiting, or mental retardation [5]. Treatment is generally sympto-
308 PEDIATRIC NEUROLOGY
Vol.8 No.4
matic because surgical removal yields poor results with almost 50% mortality in the immediate postoperative period [5]. Total removal of tumor is impossible because of vascular inclusion [6]. US findings of echogenic masses in the lateral ventricles in an asymptomatic neonate should suggest intraventricular lipomas and MRI should be performed to eliminate other associated brain malformations that may coexist and affect the prognosis in the neonate. Subsequent evaluation with CT or MRI may be required when there is an alteration in the clinical status.
Figure 3. Coronal cranial T/-weighted MRI reveals high SI lesions ia the frontal horns (curved arrows) and interhemispheric f&ares (.wai,ghr arrow) coasisrerrt rvirh fat. Low SI area (open arrows) swrorrndiag irlre~llertlisplreric lipoma is due fo chenkal shiJ artifkt.
References [l]
Buxi
TBS.
Mathur
RK.
Doda
SS. Computed
tomography
of
lipoma of corpus callosum and choroid plexus lipoma: Report of two cases. .I Comput Tomogr 1987; I 157-60. [2] lhwit CL, Barkovich AJ. Pathogenesis of intracranial lipoma: An MR study in 42 patients. AJNR 1990; 11:665-74. [3] ‘lhwit CL, Williams RG, Armstrong EA, Marlin AE. MR imaging
[S] Yock DH Jr. Choroid plexus lipomas associated with lipoma of the corpus callosum. J Comput Assist Tomogr 1980;4:678-82. [6] List CF, Holt JF, Everett M. Lipoma of the corpus callosum. A clinicopathological study. Am J Roentgen01 Radium Ther Nucl Med 194658:
125-34.
plexus lipomas. AJNR 1990: Il:2024. G. Meier P. Lipoma and agenesis of the corpus callosum with associated choroid plexus lipomas in utero diagnosis. J Ultrasound Med 1989;8:583-8.
[4]
of choroid
Mulligan
Vade and Horowitz:
Intraventricular
Lipomas
309
