Surg Neurol 199{)133:291-4
291
Intraoperative Ultrasound Imaging of the Entire Brain Through Unilateral Exploratory Burr Holes After Severe Head Injury: Technical Note Brian T. Andrews, Lawrence
M.D., Thomas
J. M a m p a l a m ,
M.D., Eric Omsberg,
M.D.,
and
H. Pitts, M.D.
Department of Neurological Surgery, School of Medicine, University of California, San Francisco, California
Andrews BT, Mampalam TJ, Omsberg E, Pitts LH. lntraoperative ultrasound imaging of the entire brain through t, nilateral expl,)ratory burr holes after severe head injury: technical note. Surg Neur,)l 19901~ ~:291 -.l
sary in most cases, unless a significant contralateral mass lesion is detected. Methods
A portable ultrasound unit with a 3.5-MHz probe allows accurate imaging of both cerebral hemispheres and partial imaging of the posterior fossa through unilateral exploratory burr holes or a craniotomy. In patients with clinical signs of transtentorial herniation after severe head injury, this unilateral technique can detect extraaxial and intraparenchymal mass lesions more accurately than is possible with bilateral exploratory burr holes. KF.Y WORDS: Intraopcrative ultrasound; Head injury; Burr holes; Subdural hematoma; Transtentorial herniation
Introduction Head-injured patients with clinical signs of brain stem compression have a high incidence of intracranial hematomas, most of which are extraaxial [ 2 , 7 - 1 0 ] . Immediate placement of bilateral exploratory burr holes allows rapid and accurate diagnosis and subsequent removal of these mass lesions, whereas unilateral exploration may miss significant hematomas [2]. Recently it has been shown that intraoperative ultrasound examination during bilateral burr-hole exploration improves the accuracy with which intraaxial lesions such as intracerebral hemorrhages and cerebral contusions can be detected [1]. In this study, use o f a low-frequency ultrasound probe with greater depth penetration allowed imaging of both cerebral hemispheres and the contralateral convexity through a unilateral intracranial exposure. This technique may make bilateral surgical exploration unneces-
Address reprtnt requests to: Brian T. Andrews, M.D., Department of Neurological Surgery, The Editorial Office, 1360 Ninth Avenue, Suite 210, San Francisco, Califi)rnia 94122 Received December 4, 19891 accepted December 28, 1989. ~.~ 1990 by Elsevier Science Publishing Co., Inc.
Patients were considered for emergency burr-hole placement only if they had clinical signs of tentorial herniation or upper brain stem compression after head trauma; details of the initial evaluation, management, and surgical technique have been described [ 1,2]. In the operating room, burr holes were placed in the temporal, frontal, and parietal regions only on the side of the dilated pupil; in the case of bilateral pupillary dilatation, burr holes were placed on the side of obvious external trauma or over the left hemisphere. The temporal burr hole was routinely enlarged to a 3 x 3-cm craniectomy. If a significant epidural or subdural h e m a t o m a was encountered, the exposure was immediately enlarged to a frontotemporoparietal craniotomy, and the h e m a t o m a was evacuated. A real-time ultrasound sector scanner (Model $2, Diasonics, Milpitas, CA) with a 3.5-MHz high-resolution probe was used. T h e tip of the probe was placed into one finger of a sterile latex glove, and the probe and cable were carefully draped with a sterile arthroscope drape (Xomed, Inc., Jacksonville, FL). Ultrasound imaging was performed by the neurosurgeon through the dura mater or directly on the cortical surface at the temporal burr-hole site to a depth that showed the midline structures, including the falx, and the contralateral hemisphere, including the calvarium (Figure 1 ). Sweeping the probe from anterior to posterior and from vertex to cranial base showed the entire supratentorial space and provided a partial view of the posterior fossa. Intraaxial lesions that appeared to be echodense were interpreted as being intracerebral hematomas if they were confluent and as contusion if they were not. Extraaxial lesions over the contralateral convexity that appeared to be echodense and compress the cerebral hemisphere were considered epidural or subdural hematomas. T h e decision to 0090-5019190/$",.50
2')2
Surg N~..urol 19()(); ~,a, :291 --t
Andrews et al
Figure 1. Axial real-time ullra.,ound image .*hou, midline falx and contralaleral ~kull convexi 0 larrou j with normal intervening brain parench3 ma.
remove a mass was made by the operating neurosurgeon based on its size, location, anti apparent mass effect. A subdural or intraventricular catheter was placed to monitor intracranial pressure. Immediately after the operation, axial, non-contrast-enhanced computed tomography (CT) scans were obtained with a GE 9800 scanner (General Electric Corp., Milwaukee, WI). The results of CT scanning were correlated with the findings of intraoperative ultrasonography.
Results
Eleven patients with posttraumatic transtentorial herniation underwent ultrasound examination of both hemispheres through a unilateral intracranial exposure. Therc' were nine males and two females; their mean age was 3 3 years (range 2 - 7 0 years). I lead trauma was the result of m o t o r vehicle-pedestrian injury in four patients, falls in three, assaults in two, and motorcycle accidents in two. At operation, significant extraaxial mass lesions were detected by direct inspection in eight patients (73~;) and were immediately evacuated through a craniotomy.
Seven patients had subdural hematomas, and one patient had an epidural hematoma. Intraoperative ultrasonography confirmed the absence of significant intracerebral mass lesions in nine of 11 patients. In one patient, ultrasonography showed diffuse bilateral cerebral contusions, which appeared as mixed echogenic and hypoechogenic areas {Figure 2), and intraventricular hemorrhage. In another, who underwent craniotomy for evacuation of a subdural hematoma, the ultrasound examination demonstrated a mass overlying the contralateral convexity. A contralateral craniotomy was then performed, and a significant subdural h e m a t o m a was evacuated. Four patients died from their neurologic and systemic insults during or soon after the operation, and their brains were examined at autopsy. C o m p u t e d tomography scans were obtained immediately after the operation in the seven patients who survived. These studies confirmed the findings of intraoperative ultrasonography in I0 ( 9 1 ~ ) o f the 11 patients. C o m p u t e d tomography scans showed a significant temporal lobe h e m a t o m a in one patient in whom burr-hole exploration and ultrasound examination were both negative. The lesion, which was subsequently evacuated through a craniot-
Intraoperativc U l t r a s o u n d Imaging
St, rg Ncurol 1990:3 a,:291 - i
295
Figure 2. Axial real-time uhraaound image Jhou's a deep frontal contuaion as a mix,,d area of increaJed echogenicio (arrowhead,.
omy, was considered by the operating surgeons to be a delayed intracerebral hematoma that probably developed after the initial exploration and ultrasonography.
Discussion The value of intraoperative ultrasound has been demonstrated in a variety of neurosurgical applications, including the imaging of enlarged ventricles, cysts, and arteriovenous malformations [5,6,11]; imaging and biopsy of intracranial tumors [3,5,6, 12, 13]; and placement of intracerebral electrodes [4 ], radioactive implants [ 14 ], and intraventricular shunts [ 11 ]. Recently, Andrews et al [ 1] showed that ultrasound imaging of the brain during exploratory burr-hole placement before CT scanning in patients with posttraumatic transtentorial herniation accurately identified intracerebral hemorrhages and contusions. However, because of the shallow penetration of the ultrasound probes used in that study, bilateral surgical exposure of the dura mater or brain was required for accurate imaging of both cerebral hemispheres, lntraoperative imaging of both hemispheres with a 3.5-MHz probe through a unilateral
exposure offers the advantage of aw)iding unnecessary surgery over the contralateral hemisphere and accurately identifies intraparenchymal mass lesions. Ultrasound examination with the 3.5-MHz probe further refines the technique of immediate exploratory burr-hole placement before CT scanning in patients with clinical signs of brain stem compression after head injury. The authors thank Cindy Huff fi)r manuscrit~t preparation and Stephen Ordway for editorial assistance.
References 1. Andrews BT, BedcrsonJ, Pitts I.H. Use of intraoperatiw_' ultrasonography to improw: the diagnostic accuracy of exploratory burr holes in patients with traumatic tentorial herniation. Neurosurgery 1989;2,1:3,t5-8. 2. Andrews BT, Pitts L!t, Lovely hiP, Bartkowski H. Is computed tomographic scanning necessary in patients with tentorial herniation? Results of immediate surgical exploration without computerized tomography in 1O0 patients. Neurosurgcry 1986; 19:4(18-14. 3. Berger MS. [Jltrasound-guided stcreotaxi~_ bu)psy using a new apparatus. J Neur()surg 1986;65:550-4. 4. Brown FD, RachlinJR, RubmJM, Fesslcr R(;, Smith LJ, Schaiblc
2 () I
Surg N c u r o l 199(); a, a,:291 - . l
KL. Ultrasound-guided periventricular stereotaxis. Neurosurgery 1983;15:162--4. 5. Chandler WF. KnakeJE, McGillicuddyJE, Lillchei K(.),Silver TM. Intraoperative use of real-tinl(_' ultrasonography in neurosur,tgery. J Neurosurg 1982;5":15"-(~3. 6. Dohrmann GJ, Rubin JM. Use of ultrasound in neurosurgical operations: a preliminary report. Surg Neurol 1981;16: ~62-6. 7. Gutterman P, Shcnkin }-tA. Prognostic i~:atures m recovery from traumatic decerebration. J Neurosurg 19-0;~2:'~ ~0-5. 8. ttoffJT, Spetzler R, Winestock D. ]lead mlury and early signs of tentorial herniation--a mamtgement dilemma West J Med 1978;28:112-(~. 9. Mahoney BD, Rockswoht GL, Ruiz E, Clinton JE. Emergent) twist-drill trephination. Neurosurgery 1 9 8 1 : 8 : 5 5 1 - L 10. Seelig JM, Greenberg RP, P,ecker DP, Miller JD, Choi SC. Re-
A n d r e w s et al
versible brainstem dysfunction following acute traun, at~c subdural hematoma. A clinical and electrophysiological study. J Neurosurg 1981:55.516-2';. l 1. Shkolnik A, McLone DG. lntraoperativc real-tilnc ultrasonic guidance of ventricular shunt placement m infants. Radiology 1981:141:515- " 12. Sii}landerU, Lmdgren P(;',ltugossonR Ultrasound sector scanning for the h)calization and biopsy of intracerebral lesions. J Neurosurg 198~:5g:'- 10. 1~. Tsutsumi Y, Andoh Y, Inoue N. Utrasound-guidcd biopsy for deep-seated brain tumors. J Neurosurg 1982;5=:164-'. l.l. TsutsumiY, Amloh Y, MatsutaniM, AsaiA. New technique for removable implantation of radionuchdcs m central nervous system neoplasm by ultrasonic guidance. Surg Neurol 1985;2'~: 520--~.
291
Intraoperative Ultrasound Imaging of the Entire Brain Through Unilateral Exploratory Burr Holes After Severe Head Injury: Technical Note Brian T. Andrews, Lawrence
M.D., Thomas
J. M a m p a l a m ,
M.D., Eric Omsberg,
M.D.,
and
H. Pitts, M.D.
Department of Neurological Surgery, School of Medicine, University of California, San Francisco, California
Andrews BT, Mampalam TJ, Omsberg E, Pitts LH. lntraoperative ultrasound imaging of the entire brain through t, nilateral expl,)ratory burr holes after severe head injury: technical note. Surg Neur,)l 19901~ ~:291 -.l
sary in most cases, unless a significant contralateral mass lesion is detected. Methods
A portable ultrasound unit with a 3.5-MHz probe allows accurate imaging of both cerebral hemispheres and partial imaging of the posterior fossa through unilateral exploratory burr holes or a craniotomy. In patients with clinical signs of transtentorial herniation after severe head injury, this unilateral technique can detect extraaxial and intraparenchymal mass lesions more accurately than is possible with bilateral exploratory burr holes. KF.Y WORDS: Intraopcrative ultrasound; Head injury; Burr holes; Subdural hematoma; Transtentorial herniation
Introduction Head-injured patients with clinical signs of brain stem compression have a high incidence of intracranial hematomas, most of which are extraaxial [ 2 , 7 - 1 0 ] . Immediate placement of bilateral exploratory burr holes allows rapid and accurate diagnosis and subsequent removal of these mass lesions, whereas unilateral exploration may miss significant hematomas [2]. Recently it has been shown that intraoperative ultrasound examination during bilateral burr-hole exploration improves the accuracy with which intraaxial lesions such as intracerebral hemorrhages and cerebral contusions can be detected [1]. In this study, use o f a low-frequency ultrasound probe with greater depth penetration allowed imaging of both cerebral hemispheres and the contralateral convexity through a unilateral intracranial exposure. This technique may make bilateral surgical exploration unneces-
Address reprtnt requests to: Brian T. Andrews, M.D., Department of Neurological Surgery, The Editorial Office, 1360 Ninth Avenue, Suite 210, San Francisco, Califi)rnia 94122 Received December 4, 19891 accepted December 28, 1989. ~.~ 1990 by Elsevier Science Publishing Co., Inc.
Patients were considered for emergency burr-hole placement only if they had clinical signs of tentorial herniation or upper brain stem compression after head trauma; details of the initial evaluation, management, and surgical technique have been described [ 1,2]. In the operating room, burr holes were placed in the temporal, frontal, and parietal regions only on the side of the dilated pupil; in the case of bilateral pupillary dilatation, burr holes were placed on the side of obvious external trauma or over the left hemisphere. The temporal burr hole was routinely enlarged to a 3 x 3-cm craniectomy. If a significant epidural or subdural h e m a t o m a was encountered, the exposure was immediately enlarged to a frontotemporoparietal craniotomy, and the h e m a t o m a was evacuated. A real-time ultrasound sector scanner (Model $2, Diasonics, Milpitas, CA) with a 3.5-MHz high-resolution probe was used. T h e tip of the probe was placed into one finger of a sterile latex glove, and the probe and cable were carefully draped with a sterile arthroscope drape (Xomed, Inc., Jacksonville, FL). Ultrasound imaging was performed by the neurosurgeon through the dura mater or directly on the cortical surface at the temporal burr-hole site to a depth that showed the midline structures, including the falx, and the contralateral hemisphere, including the calvarium (Figure 1 ). Sweeping the probe from anterior to posterior and from vertex to cranial base showed the entire supratentorial space and provided a partial view of the posterior fossa. Intraaxial lesions that appeared to be echodense were interpreted as being intracerebral hematomas if they were confluent and as contusion if they were not. Extraaxial lesions over the contralateral convexity that appeared to be echodense and compress the cerebral hemisphere were considered epidural or subdural hematomas. T h e decision to 0090-5019190/$",.50
2')2
Surg N~..urol 19()(); ~,a, :291 --t
Andrews et al
Figure 1. Axial real-time ullra.,ound image .*hou, midline falx and contralaleral ~kull convexi 0 larrou j with normal intervening brain parench3 ma.
remove a mass was made by the operating neurosurgeon based on its size, location, anti apparent mass effect. A subdural or intraventricular catheter was placed to monitor intracranial pressure. Immediately after the operation, axial, non-contrast-enhanced computed tomography (CT) scans were obtained with a GE 9800 scanner (General Electric Corp., Milwaukee, WI). The results of CT scanning were correlated with the findings of intraoperative ultrasonography.
Results
Eleven patients with posttraumatic transtentorial herniation underwent ultrasound examination of both hemispheres through a unilateral intracranial exposure. Therc' were nine males and two females; their mean age was 3 3 years (range 2 - 7 0 years). I lead trauma was the result of m o t o r vehicle-pedestrian injury in four patients, falls in three, assaults in two, and motorcycle accidents in two. At operation, significant extraaxial mass lesions were detected by direct inspection in eight patients (73~;) and were immediately evacuated through a craniotomy.
Seven patients had subdural hematomas, and one patient had an epidural hematoma. Intraoperative ultrasonography confirmed the absence of significant intracerebral mass lesions in nine of 11 patients. In one patient, ultrasonography showed diffuse bilateral cerebral contusions, which appeared as mixed echogenic and hypoechogenic areas {Figure 2), and intraventricular hemorrhage. In another, who underwent craniotomy for evacuation of a subdural hematoma, the ultrasound examination demonstrated a mass overlying the contralateral convexity. A contralateral craniotomy was then performed, and a significant subdural h e m a t o m a was evacuated. Four patients died from their neurologic and systemic insults during or soon after the operation, and their brains were examined at autopsy. C o m p u t e d tomography scans were obtained immediately after the operation in the seven patients who survived. These studies confirmed the findings of intraoperative ultrasonography in I0 ( 9 1 ~ ) o f the 11 patients. C o m p u t e d tomography scans showed a significant temporal lobe h e m a t o m a in one patient in whom burr-hole exploration and ultrasound examination were both negative. The lesion, which was subsequently evacuated through a craniot-
Intraoperativc U l t r a s o u n d Imaging
St, rg Ncurol 1990:3 a,:291 - i
295
Figure 2. Axial real-time uhraaound image Jhou's a deep frontal contuaion as a mix,,d area of increaJed echogenicio (arrowhead,.
omy, was considered by the operating surgeons to be a delayed intracerebral hematoma that probably developed after the initial exploration and ultrasonography.
Discussion The value of intraoperative ultrasound has been demonstrated in a variety of neurosurgical applications, including the imaging of enlarged ventricles, cysts, and arteriovenous malformations [5,6,11]; imaging and biopsy of intracranial tumors [3,5,6, 12, 13]; and placement of intracerebral electrodes [4 ], radioactive implants [ 14 ], and intraventricular shunts [ 11 ]. Recently, Andrews et al [ 1] showed that ultrasound imaging of the brain during exploratory burr-hole placement before CT scanning in patients with posttraumatic transtentorial herniation accurately identified intracerebral hemorrhages and contusions. However, because of the shallow penetration of the ultrasound probes used in that study, bilateral surgical exposure of the dura mater or brain was required for accurate imaging of both cerebral hemispheres, lntraoperative imaging of both hemispheres with a 3.5-MHz probe through a unilateral
exposure offers the advantage of aw)iding unnecessary surgery over the contralateral hemisphere and accurately identifies intraparenchymal mass lesions. Ultrasound examination with the 3.5-MHz probe further refines the technique of immediate exploratory burr-hole placement before CT scanning in patients with clinical signs of brain stem compression after head injury. The authors thank Cindy Huff fi)r manuscrit~t preparation and Stephen Ordway for editorial assistance.
References 1. Andrews BT, BedcrsonJ, Pitts I.H. Use of intraoperatiw_' ultrasonography to improw: the diagnostic accuracy of exploratory burr holes in patients with traumatic tentorial herniation. Neurosurgery 1989;2,1:3,t5-8. 2. Andrews BT, Pitts L!t, Lovely hiP, Bartkowski H. Is computed tomographic scanning necessary in patients with tentorial herniation? Results of immediate surgical exploration without computerized tomography in 1O0 patients. Neurosurgcry 1986; 19:4(18-14. 3. Berger MS. [Jltrasound-guided stcreotaxi~_ bu)psy using a new apparatus. J Neur()surg 1986;65:550-4. 4. Brown FD, RachlinJR, RubmJM, Fesslcr R(;, Smith LJ, Schaiblc
2 () I
Surg N c u r o l 199(); a, a,:291 - . l
KL. Ultrasound-guided periventricular stereotaxis. Neurosurgery 1983;15:162--4. 5. Chandler WF. KnakeJE, McGillicuddyJE, Lillchei K(.),Silver TM. Intraoperative use of real-tinl(_' ultrasonography in neurosur,tgery. J Neurosurg 1982;5":15"-(~3. 6. Dohrmann GJ, Rubin JM. Use of ultrasound in neurosurgical operations: a preliminary report. Surg Neurol 1981;16: ~62-6. 7. Gutterman P, Shcnkin }-tA. Prognostic i~:atures m recovery from traumatic decerebration. J Neurosurg 19-0;~2:'~ ~0-5. 8. ttoffJT, Spetzler R, Winestock D. ]lead mlury and early signs of tentorial herniation--a mamtgement dilemma West J Med 1978;28:112-(~. 9. Mahoney BD, Rockswoht GL, Ruiz E, Clinton JE. Emergent) twist-drill trephination. Neurosurgery 1 9 8 1 : 8 : 5 5 1 - L 10. Seelig JM, Greenberg RP, P,ecker DP, Miller JD, Choi SC. Re-
A n d r e w s et al
versible brainstem dysfunction following acute traun, at~c subdural hematoma. A clinical and electrophysiological study. J Neurosurg 1981:55.516-2';. l 1. Shkolnik A, McLone DG. lntraoperativc real-tilnc ultrasonic guidance of ventricular shunt placement m infants. Radiology 1981:141:515- " 12. Sii}landerU, Lmdgren P(;',ltugossonR Ultrasound sector scanning for the h)calization and biopsy of intracerebral lesions. J Neurosurg 198~:5g:'- 10. 1~. Tsutsumi Y, Andoh Y, Inoue N. Utrasound-guidcd biopsy for deep-seated brain tumors. J Neurosurg 1982;5=:164-'. l.l. TsutsumiY, Amloh Y, MatsutaniM, AsaiA. New technique for removable implantation of radionuchdcs m central nervous system neoplasm by ultrasonic guidance. Surg Neurol 1985;2'~: 520--~.
