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MRI and cerebral venous thrombosis
Computerized
Radio/. Vol. I I. No. 2. pp. 75-79, 19R7
0730-4862/X7 $3.00 + 0.00
Printedin the U.S.A. All rightsreserved
CopyrightQ 1987PergamonJournalsLtd
MRI AND CEREBRAL
VENOUS THROMBOSIS
VALERIE PLJRVIN,’ DAVID W. DUNN** and MARY EDWARDS~ *Pediatrics, and jRadiology, Indiana School of Medicine. Department of ‘,‘Neurology, ‘Ophthalmology, Indianapolis,
IN 46202,
U.S.A.
(Received 10 October 1986: received for publication 17 December
1986)
Abstract-Difficulties in the diagnosis of cerebral thrombosis are due to the nonspecificity of symptoms and signs and the infrequent occurrence on computed tomography (CT) of direct signs of cerebral sinus thrombosis, i.e. the empty delta sign and cord sign. We present two patients, a 2$year-old girl with nephrotic syndrome, coma, papilledema, and hyperdensity along the sagittal sinus on CT; and a 34-year-old man with headaches, episodic visual loss, papilledema and a normal CT following posterior fossa craniotomy. On MRI, there was increased signal in sagittal and straight sinuses in the first patient, and in the lateral sinus in the second patient. The increased signal from clot, and the absence of signal from flowing blood, make MRI the procedure of choice for the initial diagnosis of cerebral sinus thrombosis. Magnetic Blood vessels thrombosis, post-operative
MRI
SCANNING
resonance Magnetic
studies resonance
AND
Thrombosis, imaging
CEREBRAL
venous
Nephrotic
VENOUS
syndrome
Venous
THROMBOSIS
The diagnosis of cerebral venous sinus thrombosis is difficult. These patients present with variable symptoms and signs of increased intracranial pressure, focal deficits, and seizures. The changes seen on CT scanning are usually nonspecific and are seldom diagnostic. We describe two patients, both of whom developed a cerebral venous sinus thrombosis. In both cases, the clinical history and physical examination were nonspecific. In one case, the CT scan suggested a diagnosis of cerebral vein thrombosis and in the other, the CT scan was normal. In both cases, MRI allowed a conclusive diagnosis of cerebral vein thrombosis. We suggest that the MRI is the procedure of choice for the noninvasive diagnosis of cerebral venous sinus thrombosis.
CASE
REPORT
I
This child was a 2&year-old girl with a 2 month history of nephrotic syndrome. The nephrotic syndrome had initially responded to steroids; however, three weeks prior to admission, edema and proteinuria developed. One week prior to admission, she became irritable and lethargic and, on the morning of admission, she was found unresponsive. On initial examination, she had a blood pressure of 182/l 26, bilateral papilledema, and was comatose. A lumbar puncture showed a protein of 44 mg%, glucose 125 mg%, 20 white blood cells/mm3, and 686 red blood cells/mm3. The child was transferred to Riley Hospital for Children. On arrival, her systolic blood pressure was 126, she was comatose with withdrawal response to pain, and had bilateral papilledema. Laboratory studies included a hemoglobin of 14 gm%, platelets 188,000/mm3, serum sodium 143 milliequivalent/liter. BUN 4 mg%, prothrombin time 12 s, and PTT 26 s. A CT scan showed diffuse areas of decreased density throughout the cerebellum and posterior cerbral hemispheres. There was additionally an area of increased density in the right cerebellum and enhancement along the venous sinuses. The CT scan was felt to be suggestive of a cerebral venous thrombosis (Fig. 1). An MRI scan obtained 5 days after admission showed increased signal intensity from the straight sinus, sagittal sinus, and lateral sinuses on Tl weighted images (Fig. 2). The child remained hospitalized for approximately 6 weeks. Her neurologic condition changed very slowly. A gastrostomy tube was required and she was discharged on Prednisone. After discharge, the child continued to show remarkable improvement. Speech and language returned to normal. She was * Please address correspondence to: Departmemt Street, Indianapolis, IN 46202. U.S.A.
of Neurology,
75
Indiana
University
School
of Medicine.
1001 West 10th
VALERIE FURVIN et al.
Fig.
1. CT scan,
noncontrast: hypodensities in cerebellum and right parieto-occipital densities at tentorial margin and along straight sinus.
Fig. 2. MRI-TI
weighted
image:
increased
signal
intensity
along
straight
region,
and sagittal
sinus.
able to walk and run with only some minimal unsteadiness. There were fine motor pronounced on the left than the right. Visual function improved considerably.
CASE
REPORT
increased
dificits,
more
II
A 34-year-old man underwent posterior fossa craniectomy and microvascular decompression for trigeminal neuralgia unresponsive to medical management. A right retromastoid approach was employed allowing visualization of the trigeminal nerve as it exited the brainstem. The superior
MRI and cerebral venous thrombosis
Fig. 3. MRI-T2
weighted
image:
increased
signal
intensity
in right lateral
sinus.
cerebellar artery and an accompanying venous complex were found to compress the fifth nerve. In the course of surgery, the right transverse and sigmoid sinuses were exposed; gelfoam was used to control bleeding within the operative site including in direct proximity to the venous ,sinuses. Postoperatively the patient complained of headache and episodic graying out of central vision in both eyes. These episodes lasted several minutes and were exacerbated by postural change. Over the next few weeks, headaches and transient obscurations became less frequent. Complete neuro-opthalmic examination was performed 8 weeks after surgery. The general neurologic examination was normal. Visual acuity was 20/15 and Jl in each eye. Color vision was normal. Goldmann perimetry revealed enlargement of the physiologic blind spot and mild constriction of the central isopters in each eye. Pupils were reactive with no relative afferent defect. Intraocular tensions were 16 mm by applanation. Fundoscopic exam demonstrated symmetric mild opacification of the peri-papillary nerve fiber layer and capillary hyperemia (mild papilledema). A lumbar puncture was performed. The opening pressure was 310 mm of water. Protein, glucose and cell count were all normal, the VDRL was nonreactive. Two months after surgery, a magnetic resonance imaging scan was obtained which demonstrated an area of increased T2 weighted signal in the region of the right lateral sinus (Fig. 3). A diagnosis of benign intracranial hypertension secondary to venous sinus occlusion was made. The patient was treated with acetazolamide 500 mg, twice daily. He experienced progressive resolution of symptoms. On examination 2 months later, the optic discs appeared normal. Medication has since been discontinued and the patient remains well.
DISCUSSION Cerebral vein thrombosis is an uncommon disorder occurring in a variety of settings. In childhood, the most common disorders resulting in cerebral vein thrombosis are dehydration, infection, trauma, and hematologic disorders. In adults, venous sinus thrombosis has been associated with pregnancy, puerperium, oral contraceptives, primary and metastatic tumors, trauma and hematologic disorders [ 1,2]. The venous sinus thrombosis seen in Case I was presumably due to complications of the nephrotic syndrome. Both venous and arterial thromboses have been previously described in patients with
78
VALERIE PURVIN et al.
nephrotic syndrome. To the best of our knowledge, there has been only one description of dural sinus thrombosis associated with nephrotic syndrome. Lau et al., described a 2$year-old with thrombosis of the superior sagittal sinus [3]. They felt that this was due to a hypercoagulable state and documented elevations of factors five and eight and elevated platelets with deficiencies of antithrombin and plasminogen. Their patient also showed considerable improvement in functioning with rehabilitation. In Case II, the venous sinus thrombosis was a complication of surgery. Postoperative sinus thrombosis is unusual but well recognized. Two of the 56 patients reported by Chiras et al., developed venous sinus thrombosis following surgery [4]. A variety of CT scan signs have been described with cerebral vein thrombosis [2,4]. Direct signs include the cord sign, an area of hyperdensity along the thrombosed sinus, and the empty triangle or delta sign, an area of hypodensity in the lumen of the sinus surrounded by contrast enhancement of the wall of the occluded sinus. In some cases, there may be marked contrast enhancement of dural structures. In the brain parenchyma, there may be either nonhemorrhagic or hemorragic infarcts. Nonhemorrhagic infarcts can be either enhancing or nonenhancing. Normal CT scans have also been described in association with cerebral venous thrombosis. Unfortunately, the direct signs of cerebral venous thrombosis seem to be relatively unusual. In a series of 56 patients reported by Chiras et al., the empty delta sign was seen in eight cases on a first scan and on one additional case on a follow-up scan [4]. Six of these patients additionally had a cord sign. In ten cases, there was abnormal enhancement of dural structures. Two of these ten patients additionally had an empty delta sign on their scan. Nine of 56 patients had a CT which was considered normal. One additional patient showed only some minimal enlargement of lateral ventricles. Ten patients had hemorrhagic venous infarctions. The remainder of the patients had a combination of compression of lateral ventricles, focal areas of decreased density with or without subsequent contrast enhancement and normal noncontrast scans with areas of focal enhancement following a contrast infusion. Magnetic resonance imaging has been shown to be effective in the diagnosis of jugular venous thrombosis [5]. Our two cases demonstrate its value in documenting cerebral sinus thrombosis. In normally functioning venous structures, the continuing flow of blood is seen as an area of absent signal intensity. In contrast, areas of thrombosis show a marked intraluminal signal intensity, allowing a noninvasive method of diagnosing venous thrombosis. Timing of the MRI may be important. Macchi et al., have studied three patients with MRI and found that venous infarcts are seen initially as isointense areas on Tl weighted and later as hyperintense signal on both Tl and T2 weighted images. With recanalization and return of blood flow, no signal is observed [6]. Our first patient had a hyperintense Tl weighted signal by the fifth day and the second patient persistent increased signal intensity at two months, suggesting that initial isointense signals may be present only briefly and that hyperintensity persists as long as the thrombus. We believe that MRI is potentially the study of choice for documenting the existence and the extent of venous thrombosis. It offers far more accuracy than has been obtained with conventional computed tomography and avoids the risk of cerebral angiography. SUMMARY Thrombosis within cerebral venous sinuses can be accurately defined using magnetic resonance imaging. The advantage of this procedure is improved accuracy when compared to CT scanning, and the absence of potential complications seen with angiography. In this report MRI was used to document the unusual occurrence of cerebral venous sinus associated with nephrotic syndrome, and to delineate postoperative sinus thrombosis.
REFERENCES 1. H. H. Schmidek, L. M. Auer and J. P. Kapp, The cerebral venous system, Neurosurgery 17, 663478 (1985). 2. J. Chiras, J. Dubs and J. Bories, Venous infarctions, Neuroradiology 27, 593400 (1985). in the nephrotic syndrome, J. Pediatr. 3. S. 0. Lau, G. H. Bock. J. R. Edson and A. F. Michael, Sagittal sinus thrombosis 97, 948-950 (1980). 4. J. Chiras, M. G. Bousser, J. F. Meder, A. Koussa and J. Bories, CT in cerebral thrombophlebitis, Neuroradiology 27, 145-154 (1985).
MRI and cerebral venous thrombosis
19
5. I. F. Braun, J. C. Hoffman, J. A. Malko ef al., Jugular venous thrombosis: MR imaging, Radiology 157, 357.-360 (1985). 6. P. J. Macchi. R. J. Grossman, J. M. Gomori et al., High field MR imaging of cerebral venous thrombosis. J. Comput. assist. Tomogr. 10, l&l5 (1986).
About the Author-VALERIE A. PIJRV~Ngraduated from Tulane Medical School, was a resident in neurology
at Tulane, and completed a fellowship in neuro-ophthalmology at the Louisiana State University School of Medicine. She is presently Assistant Professor of Neurology and Ophthalmology and Director of the Neuro-Ophthalmology Unit at Indiana University School of Medicine. About the Author-DAVID W. DUNN graduated from Tulane Medical Center and did residences in pediatrics and neurology at Tulane. He then completed a fellowship in child neurology at Columbia Presbyterian Medical Center in New York. He is presently Director of Child Neurology at Indiana University and is an Associate Professor of Neurology and Pediatrics. About the Author-MARY
K. EDWARDSis a graduate of Indiana University. She has completed training in radiology with an additional fellowship in neuroradiology. She is presently Assistant Professor of Radiology and is Director of Neuroradiology at Riley Hospital for Children and Wishard Memorial Hospital.
Radio/. Vol. I I. No. 2. pp. 75-79, 19R7
0730-4862/X7 $3.00 + 0.00
Printedin the U.S.A. All rightsreserved
CopyrightQ 1987PergamonJournalsLtd
MRI AND CEREBRAL
VENOUS THROMBOSIS
VALERIE PLJRVIN,’ DAVID W. DUNN** and MARY EDWARDS~ *Pediatrics, and jRadiology, Indiana School of Medicine. Department of ‘,‘Neurology, ‘Ophthalmology, Indianapolis,
IN 46202,
U.S.A.
(Received 10 October 1986: received for publication 17 December
1986)
Abstract-Difficulties in the diagnosis of cerebral thrombosis are due to the nonspecificity of symptoms and signs and the infrequent occurrence on computed tomography (CT) of direct signs of cerebral sinus thrombosis, i.e. the empty delta sign and cord sign. We present two patients, a 2$year-old girl with nephrotic syndrome, coma, papilledema, and hyperdensity along the sagittal sinus on CT; and a 34-year-old man with headaches, episodic visual loss, papilledema and a normal CT following posterior fossa craniotomy. On MRI, there was increased signal in sagittal and straight sinuses in the first patient, and in the lateral sinus in the second patient. The increased signal from clot, and the absence of signal from flowing blood, make MRI the procedure of choice for the initial diagnosis of cerebral sinus thrombosis. Magnetic Blood vessels thrombosis, post-operative
MRI
SCANNING
resonance Magnetic
studies resonance
AND
Thrombosis, imaging
CEREBRAL
venous
Nephrotic
VENOUS
syndrome
Venous
THROMBOSIS
The diagnosis of cerebral venous sinus thrombosis is difficult. These patients present with variable symptoms and signs of increased intracranial pressure, focal deficits, and seizures. The changes seen on CT scanning are usually nonspecific and are seldom diagnostic. We describe two patients, both of whom developed a cerebral venous sinus thrombosis. In both cases, the clinical history and physical examination were nonspecific. In one case, the CT scan suggested a diagnosis of cerebral vein thrombosis and in the other, the CT scan was normal. In both cases, MRI allowed a conclusive diagnosis of cerebral vein thrombosis. We suggest that the MRI is the procedure of choice for the noninvasive diagnosis of cerebral venous sinus thrombosis.
CASE
REPORT
I
This child was a 2&year-old girl with a 2 month history of nephrotic syndrome. The nephrotic syndrome had initially responded to steroids; however, three weeks prior to admission, edema and proteinuria developed. One week prior to admission, she became irritable and lethargic and, on the morning of admission, she was found unresponsive. On initial examination, she had a blood pressure of 182/l 26, bilateral papilledema, and was comatose. A lumbar puncture showed a protein of 44 mg%, glucose 125 mg%, 20 white blood cells/mm3, and 686 red blood cells/mm3. The child was transferred to Riley Hospital for Children. On arrival, her systolic blood pressure was 126, she was comatose with withdrawal response to pain, and had bilateral papilledema. Laboratory studies included a hemoglobin of 14 gm%, platelets 188,000/mm3, serum sodium 143 milliequivalent/liter. BUN 4 mg%, prothrombin time 12 s, and PTT 26 s. A CT scan showed diffuse areas of decreased density throughout the cerebellum and posterior cerbral hemispheres. There was additionally an area of increased density in the right cerebellum and enhancement along the venous sinuses. The CT scan was felt to be suggestive of a cerebral venous thrombosis (Fig. 1). An MRI scan obtained 5 days after admission showed increased signal intensity from the straight sinus, sagittal sinus, and lateral sinuses on Tl weighted images (Fig. 2). The child remained hospitalized for approximately 6 weeks. Her neurologic condition changed very slowly. A gastrostomy tube was required and she was discharged on Prednisone. After discharge, the child continued to show remarkable improvement. Speech and language returned to normal. She was * Please address correspondence to: Departmemt Street, Indianapolis, IN 46202. U.S.A.
of Neurology,
75
Indiana
University
School
of Medicine.
1001 West 10th
VALERIE FURVIN et al.
Fig.
1. CT scan,
noncontrast: hypodensities in cerebellum and right parieto-occipital densities at tentorial margin and along straight sinus.
Fig. 2. MRI-TI
weighted
image:
increased
signal
intensity
along
straight
region,
and sagittal
sinus.
able to walk and run with only some minimal unsteadiness. There were fine motor pronounced on the left than the right. Visual function improved considerably.
CASE
REPORT
increased
dificits,
more
II
A 34-year-old man underwent posterior fossa craniectomy and microvascular decompression for trigeminal neuralgia unresponsive to medical management. A right retromastoid approach was employed allowing visualization of the trigeminal nerve as it exited the brainstem. The superior
MRI and cerebral venous thrombosis
Fig. 3. MRI-T2
weighted
image:
increased
signal
intensity
in right lateral
sinus.
cerebellar artery and an accompanying venous complex were found to compress the fifth nerve. In the course of surgery, the right transverse and sigmoid sinuses were exposed; gelfoam was used to control bleeding within the operative site including in direct proximity to the venous ,sinuses. Postoperatively the patient complained of headache and episodic graying out of central vision in both eyes. These episodes lasted several minutes and were exacerbated by postural change. Over the next few weeks, headaches and transient obscurations became less frequent. Complete neuro-opthalmic examination was performed 8 weeks after surgery. The general neurologic examination was normal. Visual acuity was 20/15 and Jl in each eye. Color vision was normal. Goldmann perimetry revealed enlargement of the physiologic blind spot and mild constriction of the central isopters in each eye. Pupils were reactive with no relative afferent defect. Intraocular tensions were 16 mm by applanation. Fundoscopic exam demonstrated symmetric mild opacification of the peri-papillary nerve fiber layer and capillary hyperemia (mild papilledema). A lumbar puncture was performed. The opening pressure was 310 mm of water. Protein, glucose and cell count were all normal, the VDRL was nonreactive. Two months after surgery, a magnetic resonance imaging scan was obtained which demonstrated an area of increased T2 weighted signal in the region of the right lateral sinus (Fig. 3). A diagnosis of benign intracranial hypertension secondary to venous sinus occlusion was made. The patient was treated with acetazolamide 500 mg, twice daily. He experienced progressive resolution of symptoms. On examination 2 months later, the optic discs appeared normal. Medication has since been discontinued and the patient remains well.
DISCUSSION Cerebral vein thrombosis is an uncommon disorder occurring in a variety of settings. In childhood, the most common disorders resulting in cerebral vein thrombosis are dehydration, infection, trauma, and hematologic disorders. In adults, venous sinus thrombosis has been associated with pregnancy, puerperium, oral contraceptives, primary and metastatic tumors, trauma and hematologic disorders [ 1,2]. The venous sinus thrombosis seen in Case I was presumably due to complications of the nephrotic syndrome. Both venous and arterial thromboses have been previously described in patients with
78
VALERIE PURVIN et al.
nephrotic syndrome. To the best of our knowledge, there has been only one description of dural sinus thrombosis associated with nephrotic syndrome. Lau et al., described a 2$year-old with thrombosis of the superior sagittal sinus [3]. They felt that this was due to a hypercoagulable state and documented elevations of factors five and eight and elevated platelets with deficiencies of antithrombin and plasminogen. Their patient also showed considerable improvement in functioning with rehabilitation. In Case II, the venous sinus thrombosis was a complication of surgery. Postoperative sinus thrombosis is unusual but well recognized. Two of the 56 patients reported by Chiras et al., developed venous sinus thrombosis following surgery [4]. A variety of CT scan signs have been described with cerebral vein thrombosis [2,4]. Direct signs include the cord sign, an area of hyperdensity along the thrombosed sinus, and the empty triangle or delta sign, an area of hypodensity in the lumen of the sinus surrounded by contrast enhancement of the wall of the occluded sinus. In some cases, there may be marked contrast enhancement of dural structures. In the brain parenchyma, there may be either nonhemorrhagic or hemorragic infarcts. Nonhemorrhagic infarcts can be either enhancing or nonenhancing. Normal CT scans have also been described in association with cerebral venous thrombosis. Unfortunately, the direct signs of cerebral venous thrombosis seem to be relatively unusual. In a series of 56 patients reported by Chiras et al., the empty delta sign was seen in eight cases on a first scan and on one additional case on a follow-up scan [4]. Six of these patients additionally had a cord sign. In ten cases, there was abnormal enhancement of dural structures. Two of these ten patients additionally had an empty delta sign on their scan. Nine of 56 patients had a CT which was considered normal. One additional patient showed only some minimal enlargement of lateral ventricles. Ten patients had hemorrhagic venous infarctions. The remainder of the patients had a combination of compression of lateral ventricles, focal areas of decreased density with or without subsequent contrast enhancement and normal noncontrast scans with areas of focal enhancement following a contrast infusion. Magnetic resonance imaging has been shown to be effective in the diagnosis of jugular venous thrombosis [5]. Our two cases demonstrate its value in documenting cerebral sinus thrombosis. In normally functioning venous structures, the continuing flow of blood is seen as an area of absent signal intensity. In contrast, areas of thrombosis show a marked intraluminal signal intensity, allowing a noninvasive method of diagnosing venous thrombosis. Timing of the MRI may be important. Macchi et al., have studied three patients with MRI and found that venous infarcts are seen initially as isointense areas on Tl weighted and later as hyperintense signal on both Tl and T2 weighted images. With recanalization and return of blood flow, no signal is observed [6]. Our first patient had a hyperintense Tl weighted signal by the fifth day and the second patient persistent increased signal intensity at two months, suggesting that initial isointense signals may be present only briefly and that hyperintensity persists as long as the thrombus. We believe that MRI is potentially the study of choice for documenting the existence and the extent of venous thrombosis. It offers far more accuracy than has been obtained with conventional computed tomography and avoids the risk of cerebral angiography. SUMMARY Thrombosis within cerebral venous sinuses can be accurately defined using magnetic resonance imaging. The advantage of this procedure is improved accuracy when compared to CT scanning, and the absence of potential complications seen with angiography. In this report MRI was used to document the unusual occurrence of cerebral venous sinus associated with nephrotic syndrome, and to delineate postoperative sinus thrombosis.
REFERENCES 1. H. H. Schmidek, L. M. Auer and J. P. Kapp, The cerebral venous system, Neurosurgery 17, 663478 (1985). 2. J. Chiras, J. Dubs and J. Bories, Venous infarctions, Neuroradiology 27, 593400 (1985). in the nephrotic syndrome, J. Pediatr. 3. S. 0. Lau, G. H. Bock. J. R. Edson and A. F. Michael, Sagittal sinus thrombosis 97, 948-950 (1980). 4. J. Chiras, M. G. Bousser, J. F. Meder, A. Koussa and J. Bories, CT in cerebral thrombophlebitis, Neuroradiology 27, 145-154 (1985).
MRI and cerebral venous thrombosis
19
5. I. F. Braun, J. C. Hoffman, J. A. Malko ef al., Jugular venous thrombosis: MR imaging, Radiology 157, 357.-360 (1985). 6. P. J. Macchi. R. J. Grossman, J. M. Gomori et al., High field MR imaging of cerebral venous thrombosis. J. Comput. assist. Tomogr. 10, l&l5 (1986).
About the Author-VALERIE A. PIJRV~Ngraduated from Tulane Medical School, was a resident in neurology
at Tulane, and completed a fellowship in neuro-ophthalmology at the Louisiana State University School of Medicine. She is presently Assistant Professor of Neurology and Ophthalmology and Director of the Neuro-Ophthalmology Unit at Indiana University School of Medicine. About the Author-DAVID W. DUNN graduated from Tulane Medical Center and did residences in pediatrics and neurology at Tulane. He then completed a fellowship in child neurology at Columbia Presbyterian Medical Center in New York. He is presently Director of Child Neurology at Indiana University and is an Associate Professor of Neurology and Pediatrics. About the Author-MARY
K. EDWARDSis a graduate of Indiana University. She has completed training in radiology with an additional fellowship in neuroradiology. She is presently Assistant Professor of Radiology and is Director of Neuroradiology at Riley Hospital for Children and Wishard Memorial Hospital.