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Peripheral rim enhancement in supratentorial intracerebral hematoma
Computerued 0 Pcrgamon
Tomography, Vol. 4. pp. 145 to 154 Press Ltd. 1980. Printed in the U.S.A.
PERIPHERAL SUPRATENTORIAL
RIM ENHANCEMENT IN INTRACEREBRAL HEMATOMA L. A. WEBBERG*
Department of Neurology and Psychiatry of the Tulane Medical School, Charity Hospital of New Orleans, and the Veterans Administration Hospital of New Orleans (Received 21 December 1979; received for publication 6 February 1980)
Abstract-The Computed Tomographic and clinical findings in 50 patients with peripheral ring enhancement due to intracerebral hcmatoma are presented.
Peripheral hematoma
ring enhancement
Intracerebral
hematoma
Lobar hematoma
Ganghonic-thalamic
INTRODUCTION The Computed Tomographic (CT) findings of peripheral ring enhancement (PRE) seen on postcontrast study has been described in many neuropathological conditions of both neoplastic and non-neoplastic origin [l J. This PRE pattern has been most frequently observed in patients with a supratentorial intracerebral hematoma (ICH) of hypertensive, traumatic or spontaneous etiology. In these cases certain spatial and temporal features of the PRE are quite characteristic and in certain cases the CT pattern observed on single or serial CT studies may obviate the ,need for angiography or surgical exploration. The purpose of the present study is .to describe the clinical and CT findings in 50 patients with PRE secondary to supratentorial ICH with.emphasis on the clinical-radiographic correlation. METHODS
AND PATIENTS
The clinical and CT scan findings in 50 patients whose post-contrast scan showed PRE due to an ICH were retrospectively reviewed. Almost all patients were studied utilizing an EM1 head scanner with a 160 x 160 matrix system and scan time of 1 or 4min. The scan sequence included four transverse tissue sections extending from the base to the vertex and each was 13 mm in thickness. The scan sequence was repeated following the rapid infusion of 300 ml of meglumine iothalamate (Conray-30) administered over 5 min through a 48 cm scalp vein needle. The scan sequence was performed after 200 ml had been infused and the remaining 100 ml was administered throughout the course of the post-contrast scan. In no case in which PRE was visualized was the contrast administered as a bolus injection. In 24 patients in whom PRE was visualized, follow-up scans were performed 1 week to 12 months after the initial scan. In ‘20 cases in which PRE was visualized on the second scan sequence, no post-contrast enhancement had been seen on the initial scan performed in the first week. Isotope scan was performed in 41 cases and angiogram was performed on 21 cases. Follow-up clinical evaluation was obtained for 3 months to 3 years following the ICH. No patient who showed PRE has had a subsequent episode of cerebral hemorrhage or infarction within this follow-up time interval. FINDINGS The clinical findings in these 50 patients are summarized in Table 1. All patients initially presented with focal neurological deficit. In 23 patients the progression to maximal deficit occurred * Address for correspondence: Leon A. Weisberg, M.D., Department of Neurology and Psychiatry, 1415 Tulane Avenue, New Orleans, Louisiana 70112. U.S.A. 145
L. A. WEISBERG
146
Table 1. Clinical findings in 50 patients with ICH and PRE on postcontrast scan Clinical feature 1. Onset of neurological deficit Apoplectic Evolved over 24 hr Evolved over 24-72 hr 2. Pattern of neurological deficit Seizures Hemiparesis Hemisensory deficit Homonymous hemianopsia Altered mentation 3. Predisposing factors Prior history of hypertension Hypertensive on admission Trauma 4. CSF Bloody Xanthochromic Clear 5. Isotope scan Positive Negative
Number of cases
27 13 10 10 50 41 36 I2 9 18 10 12 6 32 10 32
over 24 to 72 hr; whereas in 27 the deficit developed apoplectically and did not progress. In 32 patients there was no prior history of arterial hypertension and the patient was not hypertensive when initially evaluated in the hospital. Despite careful laboratory diagnostic evaluation, no etiology for the hemorrhage was found in these cases; therefore, these were classified as spontaneous
Fig. 1. A man struck in the forehead with a wrench. He was obtunded and had a left hemiparesis. Angiogram showed bifrontal mass effect. He was treated with corticosteroids and showed clinical improvement. CT findings (7 d post-trauma) showed bifrontal superificial high-density hematoma (left) with bilateral ovoid-shaped peripheral enhancing ring lesions (right).
Peripheral rim enhancement in supratentorial
intracerebral hematoma
Table 2. CT features in 50 patients with PRE on post-contrast CT finding 1. Location Lobar Ganglionic-Thalamic 2. Density of central region Dense Isodense Lucent 3. Mass Effect 4. Enhancing Rim Shape Regular Irregular Complete Incomplete
147
scan
Number of cases
40 10 39 5 6 14 44 6 38 12
hemorrhage. In 9 cases there was well-documented history of arterial hypertension and in these cases the PRE lesion was ganglionic-thalamic location. In 9 cases the PRE lesion was secondary to trauma (Fig. 1). The CT findings which included both plain and post-contrast patterns are listed in Table 2. Of these, 40 were lobar (Fig. 2) and 10 were primary ganglionic-thalamic (Fig. 3) in location. The temporal pattern of the enhancement was quite uniform. The earliest time interval from the onset of neurological deficit to the appearance of the enhancement was 7 d. Twenty patients were initially scanned within the first week and no post-contrast enhancement was seen but repeat scan one to two. weeks later showed PRE (Fig. 2). The longest interval following the clinical episode due to the acute bleed in which PRE was seen was 2 months. In all cases in which PRE was seen, the enhancement pattern seen on the initial scan was more intense and extensive than that seen on subsequent scans (Fig. 3) and this was irrespective of the time interval between the two scans. In none of these cases did the central portion show evidence of enhancement. In 39 cases, plain scan showed a homogeneous, consolidated, high-density central region (Fig. 2); whereas, in 6 cases the central region was low-density (Fig. 4) and in 5 it appeared isodense. It was important to obtain a complete scan sequence as in 4 cases the central region had a different appearance at different levels (Fig. 5). In 14 cases there was mass effect as defined by ventricular distortion or displacement, but in 36 cases the ventricles were normal. The enhancing rim was regular in shape in 44 cases; it was round in 26 and ovoid in 24. The enhancing rim was incompletely formed in 15 cases. In one thalamic-ganglionic hematoma, enhancement in the choroid plexus of the lateral ventricle was misinterpreted as a medial rim of enhancement of the hematoma (Fig. 6). In one most unusual case the plain scan visualized a peripheral rim of high-density on the preinfusion scan which was performed 48 hr post-bleed (Fig. 7), but this area did not enhance on the post-contrast scan. In this particular case no enhancement was seen on the post-contrast scan or on subsequent scans performed 2 and 6 weeks later. Isotope scan was performed in 41 cases always within the first 14 days post-hemorrhage, and it was positive in only 8 cases and none showed a peripheral enhancing rim. Isotope scan was performed within 7 d post-bleed in 25 cases, but was performed within 4 d of the CT scan in the other 16 cases. Angiogram showed an avascular mass in 5 of 21 cases but it did not show a hypervascular rim. No patient with ICH whose post-contrast scan showed PRE subsequently has died. This probably reflects an artifact of the selection process as PRE occurred in patients who survived the first week in which the majority of deaths in patients who have suffered an ICH usually occur. In addition, serial scans performed up to 1 year following the hemorrhage showed complete resolution of the high-density hematoma and disappearance of PRE. The involved area appeared isodense without enhancement in 18 cases and in only 6 cases was there residual evidence of low-density cystic lesion which is the more usual finding in patients with an “aged” or resolved ICH. Clinically all patients showed good clinical improvement with marked improvement of motor, sensory and aphasic deficit. Of the 10 patients who presented with seizures, only 2 had recurrent
L. A.
WEISBERG
Fig. 2. An elderly hypertensive woman developed right-sided weakness and non-fluent aphasia which became maximal over 72 hr. Isotope scan was negative. Initial scan showed left parietal (Reader’s right) non-enhancing lobar hematoma (top). Repeat scan 10d later showed high-density hematoma with peripheral ring enhancement (bottom).
Peripheral rim enhancement in supratentorial
intracerebral hematoma
Fig. 3. A normotensive man suddenly became obtunded and developed right hemiparesis. CSF was bloody; Isotope scan was negative. Initial a (10 days later) later showed left ganglionic-thalamic hematoma with extensive oval-shaped peripheral ring enhancement (top). Repeat scan 7 weeks later shows low-density ganglionic lesion with thin peripheral enhancing rim (bottom).
149
150
L. A. WEISBERG
Fig. 4. 4 60 year-old normotensive developed headache and became obtunded with left hemiparesis. CSF was bloody; Isotope scan was negative. CT findings (2 weeks later) showed right parietal lucent lesion with peripheral enhancing rim.
Fig. 5. A 52 year-old normotensive man developed left hemiparesis-sensory syndrome. CSF was clear; Isotope scan was negative. CT findings (8 d later) showed right ganglionic high-density hematoma with peripheral enhancement (left). At higher section. peripheral ring with an isodense central region is visualized (right).
Peripheral rim enhancement in supratentorial
intracerebral hematoma
Fig. 6. Right thalamic hematoma (left) with thin medial rim of enhancement representing the choroid plexus of the third ventricle (right).
Fig. 7. A 36 year-old hypertensive man developed headache and left hemiparesis. CSF was clear. Isotope scan was negative. a findings (3 d later) showed right ganglionic high-density hematoma with thin peripheral rim seen on non-contrast scan. No enhancement was seen on post-contrast scan.
151
152
L. A. WEISBERG
seizures which were well-controlled with anticonvulsant medication. Only 2 patients have subsequently developed an electroencephalographic epileptogenic focus or clinical seizures. DISCUSSION The findings of peripheral ring enhancement (PRE) in 50 cases on intracerebral hematoma is quite important [2, 31 as this pattern was initially thought to indicate the presence of neoplasm (primary or metastatic), abscess or aneurysm. From an analysis of the specific CT patterns observed in these 50 cases, it appears that it is not always possible to differentiate PRE due to ICH from these other conditions based upon single scan pattern, but that this differentiation was possible with serial scans in all cases. The accuracy of the CT scan diagnosis was confirmed by angiography, clinical course or follow-up scan. Certain of the CT features of PRE due to ICH should be emphasized. In only one case was there evidence of a high-density peripheral rim on the pre-enhancement scan, and this region did not enhance on the post-contrast scan on this or subsequent follow-up scans which were-obtained at a time interval when peripheral rim enhancement was usually found to occur. This finding of a rim on the pre-enhanced scan has been reported previously [4]. The finding of a high-density ring on the non-enhanced scan surrounded by an irregularly marginated low-density portion was frequently seen in malignant neoplasms and abscesses, but this region always showed post-contrast enhancement in these conditions this was an important differentiating feature from PRE due to ICH (Fig. 8). When the central region appeared as non-calcified high-density there was less difficulty in diagnosis than when this appeared as a decreased or isodense region. The density characteristics of the central region was dependent upon the size of the hematoma and the time interval since the intracerebral hemorrhage occurred. The peripheral enhancing rim was usually thin and regular in shape. It was quite striking that although there was dense and extensive enhancement in this peripheral rim, there was minimal evidence of mass effect. PRE was visualized in other conditions but usually these could be differentiated by certain characteristic patterns. The peripheral enhancing rim of neoplasms was more irregular in shape and
Fig. 8. Plain scan shows right parietal-occipital low-density lesion with high-density peripheral rim (left) which shows dense irregular ring consistent with a malignant neoplasm (right).
Peripheral rim enhancement in supratentorial
intracerebral hematoma
153
thickness. In addition the lesion caused more mass effect with extensive surrounding low-density portion (Fig. 9). Furthermore, in most cases of malignant neoplasms the pre-enhanced scan showed evidence of a high-density peripheral region which further enhanced on the post-contrast scan. Abscesses showed peripheral enhancement but the presence of multiple rings, satellite nodular lesions or enhancement which was denser on its gray than white matter surface was quite characteristic of its inflammatory etiology. In two surgically pathologically confirmed cases of gliosis without neoplasia, an enhancing rim was visualized. This enhancing ring was thick as contrasted to the
154
L. A. WEISBERG
About the AUUIIX-LEON ARNOLDWEISEZERG received his B.A. from Yale University in 1963 and M.D. from Columbia Medical School in 1968. Dr Weisberg completed his neurology residency at the Neurological .Institute of the Columbia-Presbyterian Medical Center in 1972. He is presently Associate Professor of Neurology at Tulane Medical Center and Charity Hospital of New Orleans. He is senior Author of the book Cerebral Computed Tomography: a Text-Atlas.
Tomography, Vol. 4. pp. 145 to 154 Press Ltd. 1980. Printed in the U.S.A.
PERIPHERAL SUPRATENTORIAL
RIM ENHANCEMENT IN INTRACEREBRAL HEMATOMA L. A. WEBBERG*
Department of Neurology and Psychiatry of the Tulane Medical School, Charity Hospital of New Orleans, and the Veterans Administration Hospital of New Orleans (Received 21 December 1979; received for publication 6 February 1980)
Abstract-The Computed Tomographic and clinical findings in 50 patients with peripheral ring enhancement due to intracerebral hcmatoma are presented.
Peripheral hematoma
ring enhancement
Intracerebral
hematoma
Lobar hematoma
Ganghonic-thalamic
INTRODUCTION The Computed Tomographic (CT) findings of peripheral ring enhancement (PRE) seen on postcontrast study has been described in many neuropathological conditions of both neoplastic and non-neoplastic origin [l J. This PRE pattern has been most frequently observed in patients with a supratentorial intracerebral hematoma (ICH) of hypertensive, traumatic or spontaneous etiology. In these cases certain spatial and temporal features of the PRE are quite characteristic and in certain cases the CT pattern observed on single or serial CT studies may obviate the ,need for angiography or surgical exploration. The purpose of the present study is .to describe the clinical and CT findings in 50 patients with PRE secondary to supratentorial ICH with.emphasis on the clinical-radiographic correlation. METHODS
AND PATIENTS
The clinical and CT scan findings in 50 patients whose post-contrast scan showed PRE due to an ICH were retrospectively reviewed. Almost all patients were studied utilizing an EM1 head scanner with a 160 x 160 matrix system and scan time of 1 or 4min. The scan sequence included four transverse tissue sections extending from the base to the vertex and each was 13 mm in thickness. The scan sequence was repeated following the rapid infusion of 300 ml of meglumine iothalamate (Conray-30) administered over 5 min through a 48 cm scalp vein needle. The scan sequence was performed after 200 ml had been infused and the remaining 100 ml was administered throughout the course of the post-contrast scan. In no case in which PRE was visualized was the contrast administered as a bolus injection. In 24 patients in whom PRE was visualized, follow-up scans were performed 1 week to 12 months after the initial scan. In ‘20 cases in which PRE was visualized on the second scan sequence, no post-contrast enhancement had been seen on the initial scan performed in the first week. Isotope scan was performed in 41 cases and angiogram was performed on 21 cases. Follow-up clinical evaluation was obtained for 3 months to 3 years following the ICH. No patient who showed PRE has had a subsequent episode of cerebral hemorrhage or infarction within this follow-up time interval. FINDINGS The clinical findings in these 50 patients are summarized in Table 1. All patients initially presented with focal neurological deficit. In 23 patients the progression to maximal deficit occurred * Address for correspondence: Leon A. Weisberg, M.D., Department of Neurology and Psychiatry, 1415 Tulane Avenue, New Orleans, Louisiana 70112. U.S.A. 145
L. A. WEISBERG
146
Table 1. Clinical findings in 50 patients with ICH and PRE on postcontrast scan Clinical feature 1. Onset of neurological deficit Apoplectic Evolved over 24 hr Evolved over 24-72 hr 2. Pattern of neurological deficit Seizures Hemiparesis Hemisensory deficit Homonymous hemianopsia Altered mentation 3. Predisposing factors Prior history of hypertension Hypertensive on admission Trauma 4. CSF Bloody Xanthochromic Clear 5. Isotope scan Positive Negative
Number of cases
27 13 10 10 50 41 36 I2 9 18 10 12 6 32 10 32
over 24 to 72 hr; whereas in 27 the deficit developed apoplectically and did not progress. In 32 patients there was no prior history of arterial hypertension and the patient was not hypertensive when initially evaluated in the hospital. Despite careful laboratory diagnostic evaluation, no etiology for the hemorrhage was found in these cases; therefore, these were classified as spontaneous
Fig. 1. A man struck in the forehead with a wrench. He was obtunded and had a left hemiparesis. Angiogram showed bifrontal mass effect. He was treated with corticosteroids and showed clinical improvement. CT findings (7 d post-trauma) showed bifrontal superificial high-density hematoma (left) with bilateral ovoid-shaped peripheral enhancing ring lesions (right).
Peripheral rim enhancement in supratentorial
intracerebral hematoma
Table 2. CT features in 50 patients with PRE on post-contrast CT finding 1. Location Lobar Ganglionic-Thalamic 2. Density of central region Dense Isodense Lucent 3. Mass Effect 4. Enhancing Rim Shape Regular Irregular Complete Incomplete
147
scan
Number of cases
40 10 39 5 6 14 44 6 38 12
hemorrhage. In 9 cases there was well-documented history of arterial hypertension and in these cases the PRE lesion was ganglionic-thalamic location. In 9 cases the PRE lesion was secondary to trauma (Fig. 1). The CT findings which included both plain and post-contrast patterns are listed in Table 2. Of these, 40 were lobar (Fig. 2) and 10 were primary ganglionic-thalamic (Fig. 3) in location. The temporal pattern of the enhancement was quite uniform. The earliest time interval from the onset of neurological deficit to the appearance of the enhancement was 7 d. Twenty patients were initially scanned within the first week and no post-contrast enhancement was seen but repeat scan one to two. weeks later showed PRE (Fig. 2). The longest interval following the clinical episode due to the acute bleed in which PRE was seen was 2 months. In all cases in which PRE was seen, the enhancement pattern seen on the initial scan was more intense and extensive than that seen on subsequent scans (Fig. 3) and this was irrespective of the time interval between the two scans. In none of these cases did the central portion show evidence of enhancement. In 39 cases, plain scan showed a homogeneous, consolidated, high-density central region (Fig. 2); whereas, in 6 cases the central region was low-density (Fig. 4) and in 5 it appeared isodense. It was important to obtain a complete scan sequence as in 4 cases the central region had a different appearance at different levels (Fig. 5). In 14 cases there was mass effect as defined by ventricular distortion or displacement, but in 36 cases the ventricles were normal. The enhancing rim was regular in shape in 44 cases; it was round in 26 and ovoid in 24. The enhancing rim was incompletely formed in 15 cases. In one thalamic-ganglionic hematoma, enhancement in the choroid plexus of the lateral ventricle was misinterpreted as a medial rim of enhancement of the hematoma (Fig. 6). In one most unusual case the plain scan visualized a peripheral rim of high-density on the preinfusion scan which was performed 48 hr post-bleed (Fig. 7), but this area did not enhance on the post-contrast scan. In this particular case no enhancement was seen on the post-contrast scan or on subsequent scans performed 2 and 6 weeks later. Isotope scan was performed in 41 cases always within the first 14 days post-hemorrhage, and it was positive in only 8 cases and none showed a peripheral enhancing rim. Isotope scan was performed within 7 d post-bleed in 25 cases, but was performed within 4 d of the CT scan in the other 16 cases. Angiogram showed an avascular mass in 5 of 21 cases but it did not show a hypervascular rim. No patient with ICH whose post-contrast scan showed PRE subsequently has died. This probably reflects an artifact of the selection process as PRE occurred in patients who survived the first week in which the majority of deaths in patients who have suffered an ICH usually occur. In addition, serial scans performed up to 1 year following the hemorrhage showed complete resolution of the high-density hematoma and disappearance of PRE. The involved area appeared isodense without enhancement in 18 cases and in only 6 cases was there residual evidence of low-density cystic lesion which is the more usual finding in patients with an “aged” or resolved ICH. Clinically all patients showed good clinical improvement with marked improvement of motor, sensory and aphasic deficit. Of the 10 patients who presented with seizures, only 2 had recurrent
L. A.
WEISBERG
Fig. 2. An elderly hypertensive woman developed right-sided weakness and non-fluent aphasia which became maximal over 72 hr. Isotope scan was negative. Initial scan showed left parietal (Reader’s right) non-enhancing lobar hematoma (top). Repeat scan 10d later showed high-density hematoma with peripheral ring enhancement (bottom).
Peripheral rim enhancement in supratentorial
intracerebral hematoma
Fig. 3. A normotensive man suddenly became obtunded and developed right hemiparesis. CSF was bloody; Isotope scan was negative. Initial a (10 days later) later showed left ganglionic-thalamic hematoma with extensive oval-shaped peripheral ring enhancement (top). Repeat scan 7 weeks later shows low-density ganglionic lesion with thin peripheral enhancing rim (bottom).
149
150
L. A. WEISBERG
Fig. 4. 4 60 year-old normotensive developed headache and became obtunded with left hemiparesis. CSF was bloody; Isotope scan was negative. CT findings (2 weeks later) showed right parietal lucent lesion with peripheral enhancing rim.
Fig. 5. A 52 year-old normotensive man developed left hemiparesis-sensory syndrome. CSF was clear; Isotope scan was negative. CT findings (8 d later) showed right ganglionic high-density hematoma with peripheral enhancement (left). At higher section. peripheral ring with an isodense central region is visualized (right).
Peripheral rim enhancement in supratentorial
intracerebral hematoma
Fig. 6. Right thalamic hematoma (left) with thin medial rim of enhancement representing the choroid plexus of the third ventricle (right).
Fig. 7. A 36 year-old hypertensive man developed headache and left hemiparesis. CSF was clear. Isotope scan was negative. a findings (3 d later) showed right ganglionic high-density hematoma with thin peripheral rim seen on non-contrast scan. No enhancement was seen on post-contrast scan.
151
152
L. A. WEISBERG
seizures which were well-controlled with anticonvulsant medication. Only 2 patients have subsequently developed an electroencephalographic epileptogenic focus or clinical seizures. DISCUSSION The findings of peripheral ring enhancement (PRE) in 50 cases on intracerebral hematoma is quite important [2, 31 as this pattern was initially thought to indicate the presence of neoplasm (primary or metastatic), abscess or aneurysm. From an analysis of the specific CT patterns observed in these 50 cases, it appears that it is not always possible to differentiate PRE due to ICH from these other conditions based upon single scan pattern, but that this differentiation was possible with serial scans in all cases. The accuracy of the CT scan diagnosis was confirmed by angiography, clinical course or follow-up scan. Certain of the CT features of PRE due to ICH should be emphasized. In only one case was there evidence of a high-density peripheral rim on the pre-enhancement scan, and this region did not enhance on the post-contrast scan on this or subsequent follow-up scans which were-obtained at a time interval when peripheral rim enhancement was usually found to occur. This finding of a rim on the pre-enhanced scan has been reported previously [4]. The finding of a high-density ring on the non-enhanced scan surrounded by an irregularly marginated low-density portion was frequently seen in malignant neoplasms and abscesses, but this region always showed post-contrast enhancement in these conditions this was an important differentiating feature from PRE due to ICH (Fig. 8). When the central region appeared as non-calcified high-density there was less difficulty in diagnosis than when this appeared as a decreased or isodense region. The density characteristics of the central region was dependent upon the size of the hematoma and the time interval since the intracerebral hemorrhage occurred. The peripheral enhancing rim was usually thin and regular in shape. It was quite striking that although there was dense and extensive enhancement in this peripheral rim, there was minimal evidence of mass effect. PRE was visualized in other conditions but usually these could be differentiated by certain characteristic patterns. The peripheral enhancing rim of neoplasms was more irregular in shape and
Fig. 8. Plain scan shows right parietal-occipital low-density lesion with high-density peripheral rim (left) which shows dense irregular ring consistent with a malignant neoplasm (right).
Peripheral rim enhancement in supratentorial
intracerebral hematoma
153
thickness. In addition the lesion caused more mass effect with extensive surrounding low-density portion (Fig. 9). Furthermore, in most cases of malignant neoplasms the pre-enhanced scan showed evidence of a high-density peripheral region which further enhanced on the post-contrast scan. Abscesses showed peripheral enhancement but the presence of multiple rings, satellite nodular lesions or enhancement which was denser on its gray than white matter surface was quite characteristic of its inflammatory etiology. In two surgically pathologically confirmed cases of gliosis without neoplasia, an enhancing rim was visualized. This enhancing ring was thick as contrasted to the
154
L. A. WEISBERG
About the AUUIIX-LEON ARNOLDWEISEZERG received his B.A. from Yale University in 1963 and M.D. from Columbia Medical School in 1968. Dr Weisberg completed his neurology residency at the Neurological .Institute of the Columbia-Presbyterian Medical Center in 1972. He is presently Associate Professor of Neurology at Tulane Medical Center and Charity Hospital of New Orleans. He is senior Author of the book Cerebral Computed Tomography: a Text-Atlas.