1977, British Journal of Radiology, 50, 706-709
Aneurysmal bone cyst of clavicle By J . Smith, M.B., M.R.C.P., F.R.C.R. Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA {Received December, 1976 and in revised form March, 1977) ABSTRACT
Two aneurysmal bone cysts are described. They presented difficulties in diagnosis because the patients were rather older than usual for this lesion and because of the uncommon location of the cysts. The nature of aneurysmal bone cysts is discussed. Aneurysmal bone cyst (A.B.C.) is a striking and well named lesion of bone with characteristic histological and radiological features. It is a disease mainly of the young with a peak incidence in the second decade. However, it may on occasion occur in the elderly and the very young (Dominok et al., 1971). Virtually any bone may be involved but the most frequent sites are the long tubular bones and the vertebrae. A review of primary tumours of the clavicle and scapula (Smith et al., 1975) revealed two patients in the seventh decade with A.B.C. of the clavicle. Despite very characteristic radiological features the unusual age coupled with the uncommon site led to diagnostic difficulty. Because of these factors this report is felt to be of interest.
The lesion was thought to be benign and the differential diagnosis rested between a sub-periosteal haematoma and an unusual giant cell tumour. The distal half of the clavicle was resected and the cut surgical specimen (Fig. 3) demonstrated the eccentric mass with honeycomb spaces, many containing blood. Histoligically, the normal architecture was replaced by numerous, dilated, engorged, vascular channels. Extravasation of blood was noted in several places. The
FIG. 2. Case 1. Four months later showing healing of fracture and a honeycomb mass of small spaces lined by bone.
CASE HISTORIES
Case 1 A 61-year-old woman presented with a swelling of the lateral end of her left clavicle for one month. Six months earlier she had fallen down stairs and fractured the same clavicle (Fig. 1). This had been treated by immobilization with a crepe bandage and three months later the fracture had healed completely. Two months after this she again noted tenderness and swelling over the clavicle for the first time since the fracture had healed. On examination she was found to have a 4 cm tender swelling over the superior surface of the clavicle. The radiograph (Fig. 2) at this time showed an eccentric honeycomb mass of small cysts with thin cortical linings. The fracture had united with some angulation.
FIG. 1. Case 1. Showing a fracture with callus superiorly. Translucency on either side of the fracture line raises the suspicion of an underlying disease process.
FIG. 3. Case 1. Cut surgical specimen of distal half of clavicle. Honeycomb pattern with blood within the spaces. 706
r OCTOBER 1977
Aneurysmal bone cyst of clavicle fibrous tissue was mature and well collagenized. Multinucleated giant cells were noted in close proximity to the vascular channels. The giant cells were much smaller and with smaller nuclei than one usually sees in giant cell tumour. The appearances were typical of an aneurysmal bone cyst.
DISCUSSION
Aneurysmal bone cyst occurring in the seventh decade is clearly uncommon. However, Dominok et al. (1971) reported three patients in the seventh decade and review of the literature revealed the oldest patient as 72 years old. The clavicle is also an Comment The radiograph taken a month after the injury (Fig. 1) uncommon site but perusal of the literature, text shows the angulated fracture with callus formation. There is books and atlases reveal approximately 25 cases. In a translucency on either side of the fracture suggesting that our institution, with a large bone tumour service, this was a pathological fracture. However, microscopic examination of the specimen revealed no abnormality other there are six well documented cases. than aneurysmal bone cyst. The four other patients were aged 12, 13, 20 and 24 years. Altogether there are approximately 90 cases Case 2 of A.B.C. recorded in our registry. The clavicle is by A 63-year-old woman had noticed a lump in her left no means the least common site. Lesions of the rib, shoulder for three months. Preceded by a mild ache, the lump had slowly increased in size. On examination, she was skull and mandible are less frequent. found to have a bony hard mass over the distal end of the However, although the radiological manifestations left clavicle. It was not tender and measured approximately 6 cm in length. The radiograph (Fig. 4) shows eccentric are now well recognized (Sherman and Soong, 1957), expansion superiorly of the acromial end of the left clavicle. the exact nature of this unusual lesion of bone is still A thin, crescentic cortical rim outlines the lateral half of the poorly understood. The concept of aneurysmal bone mass. On the medial side the cortical margin can no longer be seen. There appears to be some inner texture to the mass cyst as a non-neoplastic lesion, quite different from but no definite honeycombing is seen. Radiographs of the the giant cell tumour, was first introduced by Jaffe rest of the skeleton were unremarkable. Needle biopsy of and Lichtenstein in 1942. Based on two cases only, the mass, immediately prior to operation, revealed benign fibrous tissue with giant cells, consistent with a bone cyst it took more than a decade for its general acceptance. lining. At operation the distal half of the clavicle was Individual papers by Jaffe (1950) and Lichtenstein resected. The surgical specimen (Fig. 5) revealed a mass studded with cysts containing blood. The individual cystic spaces appear larger than in the previous case but the similarity is striking. Histologically the appearances were similar to Case 1. There was more extravasation of blood and the vascular pattern a little more irregular. Fine osteoid formation was noted in several areas. Comment Both radiologist and surgeon felt that the clinical picture and radiographs indicated an aneurysmal bone cyst but because of the age of the patient and the unusual site, a primary tumour of the clavicle such as a chondrosarcoma or a solitary metastasis were thought to be more likely.
•\
FIG. 4. Case 2. Eccentric expanding lesion extending superiorly. Linear shadows suggesting septa are well seen. The cortical rim is lost medially raising the question of malignancy.
I;
FIG. 5. Case 2. Cut surgical specimen showing large spaces containing blood.
707
VOL.
50, No. 598 J. Smith
(1975) claimed that 50% of aneurysmal bone cysts show an underlying primary neoplasm either benign or malignant. Edeiken and Hodes (1973) also found benign and malignant neoplasms associated with aneurysmal bone cyst. Biesecker et al. (1970) found benign bone lesions such as non-ossifying fibroma, chondroblastoma, osteoblastoma and true giant-cell tumour in 30% of cases. However, Tillman et al. (1968) were unable to find any associated neoplasm in 95 cases despite careful scrutiny. Clough and Price (1968) were also clearly sceptical about an association with an underlying neoplasm. We have not seen any association in this institution between malignant neoplasms and aneurysmal bone cyst. This is clearly of considerable therapeutic importance and any cases of aneurysmal bone cyst associated with osteogenic sarcoma or other FIG. 6. Cut section of aneurysmal bone cyst of clavicle in 20-year- malignant tumour deserve to be reported. We do not old patient. The sponge-like appearance is well demon- refer, of course, to telangiectatic osteogenic sarcoma strated. mistakenly diagnosed as aneurysmal bone cyst but a true A.B.C. associated with an underlying malignant (1950) based upon 30 cases led to more general bone tumour. recognition. Prior to this the lesion had been known With regard to associated factors, the first case is under a variety of names. of interest since there was a clear history of trauma In our institution, it has been referred to as sub- and the radiograph strongly suggested an underlying periosteal giant cell tumour (Coley, 1949), and lesion. Since the specimen showed no evidence of atypical giant cell tumour (Coley and Miller, 1942). any other lesion apart from the aneurysmal bone Ewing (1940) referred to it as aneurysmal giant cell cyst, one can only speculate on this. Benign lesions tumour. Many other names have been used (Sher- of the clavicle are uncommon, in particular the giant man and Soong, 1957) but all these earlier authors cell tumour which is excessively rare. If one discards felt that it was related in some way to the giant cell cases reported prior to 1950, and perhaps even a tumour. little later, very few giant cell tumours of the The interior of the lesion consists of multiple clavicle have been recorded, the majority previously vascular channels. In fact, it is not truly a cyst since reported being, in fact, aneurysmal bone cysts. it more closely resembles a sponge (Fig. 6). The walls Lichtenstein (1959) has never seen a true giant cell of the vascular channels may be either thick or thin tumour of the clavicle. It is possible that this was and there may be strips of osteoid tissue or immature simply an unusual simple fracture. trabeculae in the walls. A variable number of benign giant cells may also be found. Blood may be present REFERENCES throughout the cyst or only in part and in long AEGERTER, E. E., and KIRKPATRICK, J. A., 1975. Orthopaedic standing cases it may be simply blood tinged. Diseases, 3rd edn (W. B. Saunders Company, Philadelphia). Lichtenstein (1950) claimed that the underlying BIESECKER, J. L., MARCOVE, R. C , HUVOS, A. G., and abnormality was an arteriovenous communication. MIKE, V., 1970. Aneurysmal bone cysts. Cancer, 26, 615-625. Biesecker et al. (1970) measured pressures within the J. R., and PRICE, C. H. G., 1968. Aneurysmal bone cysts and in three of six patients these were above CLOUGH, cysts. Review of 12 cases. Journal of Bone and Joint the venous pressure. Surgery, 50B, 116-127. Trauma has frequently been mentioned as an COLEV, B. L., and MILLER, L. E., 1942. Atypical giant cell tumor. American Journal of Roentgenology, 47, 541-548. aetiological factor and over 50% of patients give a COLEY, B. L., 1949. Neoplasms of bone and related conditions. history of trauma. In recent years there has been a Their etiology, pathogenesis, diagnosis and treatment (Paul B. Hoeber, Inc., New York). very definite trend suggesting that the aneurysmal DOMINOK, G. W., KNOCH, H. G., MANJA, B., and SCHULZE, bone cyst is a secondary phenomenon and that a K. J., 1971. Die aneurysmatische Knochencyste. Langenvariety of tumours, both benign and malignant, may becks Archievefur Chirurgie, 328, 153-168. be the primary lesion which initiates the arterio- EDEIKEN, J., and HODES, P. J., 1973. Roentgen diagnosis of diseases of bone, 2nd edn, Vol. 2 (The Williams & Wilkins venous communication. Aegerter and Kirkpatrick Company, Baltimore). 708
Aneurysmal bone cyst of clavicle 1959. Bone tumours, 2nd edn, pp. 121 (C. V. Mosby, EWING, J., 1940. Neoplastic diseases. In A treatise on tumors, St. Louis). 4th edn, pp. 323-324 (W. B. Saunders Company, SHERMAN, R. S., and SOONG, K. Y., 1957. Aneurysmal bone Philadelphia). cyst: its roentgen diagnosis. Radiology, 68, 54—64. JAFFE, H. L., and LICHTENSTEIN, L., 1942. Solitary unicameral bone cysts with emphasis on the roentgen picture, SMITH, J., MCLACHIAN, D., HUVOS, A. G., and HIGINBOTHAM, N. L., 1975. Primary tumors of the clavicle and the pathologic appearance and the pathogenesis. Archives scapula. American Journal of Roentgenology, 124, 113-123. of Surgery, 44, 1004-1025. JAFFE, H. L., 1950. Aneurysmal bone cyst. Bulletin of the TILLMAN, B. P., DAHLIN, D. C , LIPSCOMB, P. R., and STEWART, J. R., 1968. Aneurysmal bone cyst: an analysis Hospital for Joint Diseases, 11, 3 - 1 3 . of ninety-five cases. Mayo Clinic Proceedings, 43, 478-495. LICHTENSTEIN, L., 1950. Aneurysmal bone cyst. Cancer, 3, 279-289.
Book review Ultrasonic Encephalography II. By D. N. White, pp. 312,becomes greater in cases of cerebral disease where display of illus., 1976 (Canada, Ultramedison), $35.00. the M echo becomes more difficult than from healthy This book follows seven years after the author's first book persons". The author also states that "Any test that achieves 99.8% accuracy is to be lauded regardless how the on the subject. During that time non-cerebral ultrasound imaging has leapt forward, while encephalography has made accuracy is achieved"; few would agree with this, especially little progress and computerized X-ray tomography is now as the authors published work shows an accuracy rate of only widely available. This book is a broad review of the subject 55%. In the last few years automatic devices have been deveand is intended to explain in non-specialized terms, the severe fundamental physical limitations which have loped in an attempt to improve the reliability of this prevented the development of ultrasound encephalography. technique and these are described in detail in Chapter 7. The acoustic properties of the skull are dealt with in The results obtained with them show no evidence of the detail in the first two chapters while the "characteristics" of anticipated improvement. the midline "M" echo are discussed in Chapter 3. The three The last two chapters discuss a dozen other ultrasound subsequent chapters describe and discuss the use of the techniques which have been applied to cerebral diagnosis conventional video technique and many published series of and, with the exception of the Doppler blood flow studies, results are presented and compared, the false positive rates none seems to have gained clinical acceptance yet. varying from 0.1 to 44% and the false negative rates from This book is a very comprehensive review of the whole 0 to 14%. There is clearly a very high degree of dependance field of cerebral ultrasound and will be of interest to upon operator expertise which the author acknowledges and protagonists of the technique but will also supply antagohe also states "The need for the clinical operator or interpre- nists with much ammunition. tor to use his clinical bias in order to achieve accuracy H. B. MEIRE.
709
Aneurysmal bone cyst of clavicle By J . Smith, M.B., M.R.C.P., F.R.C.R. Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA {Received December, 1976 and in revised form March, 1977) ABSTRACT
Two aneurysmal bone cysts are described. They presented difficulties in diagnosis because the patients were rather older than usual for this lesion and because of the uncommon location of the cysts. The nature of aneurysmal bone cysts is discussed. Aneurysmal bone cyst (A.B.C.) is a striking and well named lesion of bone with characteristic histological and radiological features. It is a disease mainly of the young with a peak incidence in the second decade. However, it may on occasion occur in the elderly and the very young (Dominok et al., 1971). Virtually any bone may be involved but the most frequent sites are the long tubular bones and the vertebrae. A review of primary tumours of the clavicle and scapula (Smith et al., 1975) revealed two patients in the seventh decade with A.B.C. of the clavicle. Despite very characteristic radiological features the unusual age coupled with the uncommon site led to diagnostic difficulty. Because of these factors this report is felt to be of interest.
The lesion was thought to be benign and the differential diagnosis rested between a sub-periosteal haematoma and an unusual giant cell tumour. The distal half of the clavicle was resected and the cut surgical specimen (Fig. 3) demonstrated the eccentric mass with honeycomb spaces, many containing blood. Histoligically, the normal architecture was replaced by numerous, dilated, engorged, vascular channels. Extravasation of blood was noted in several places. The
FIG. 2. Case 1. Four months later showing healing of fracture and a honeycomb mass of small spaces lined by bone.
CASE HISTORIES
Case 1 A 61-year-old woman presented with a swelling of the lateral end of her left clavicle for one month. Six months earlier she had fallen down stairs and fractured the same clavicle (Fig. 1). This had been treated by immobilization with a crepe bandage and three months later the fracture had healed completely. Two months after this she again noted tenderness and swelling over the clavicle for the first time since the fracture had healed. On examination she was found to have a 4 cm tender swelling over the superior surface of the clavicle. The radiograph (Fig. 2) at this time showed an eccentric honeycomb mass of small cysts with thin cortical linings. The fracture had united with some angulation.
FIG. 1. Case 1. Showing a fracture with callus superiorly. Translucency on either side of the fracture line raises the suspicion of an underlying disease process.
FIG. 3. Case 1. Cut surgical specimen of distal half of clavicle. Honeycomb pattern with blood within the spaces. 706
r OCTOBER 1977
Aneurysmal bone cyst of clavicle fibrous tissue was mature and well collagenized. Multinucleated giant cells were noted in close proximity to the vascular channels. The giant cells were much smaller and with smaller nuclei than one usually sees in giant cell tumour. The appearances were typical of an aneurysmal bone cyst.
DISCUSSION
Aneurysmal bone cyst occurring in the seventh decade is clearly uncommon. However, Dominok et al. (1971) reported three patients in the seventh decade and review of the literature revealed the oldest patient as 72 years old. The clavicle is also an Comment The radiograph taken a month after the injury (Fig. 1) uncommon site but perusal of the literature, text shows the angulated fracture with callus formation. There is books and atlases reveal approximately 25 cases. In a translucency on either side of the fracture suggesting that our institution, with a large bone tumour service, this was a pathological fracture. However, microscopic examination of the specimen revealed no abnormality other there are six well documented cases. than aneurysmal bone cyst. The four other patients were aged 12, 13, 20 and 24 years. Altogether there are approximately 90 cases Case 2 of A.B.C. recorded in our registry. The clavicle is by A 63-year-old woman had noticed a lump in her left no means the least common site. Lesions of the rib, shoulder for three months. Preceded by a mild ache, the lump had slowly increased in size. On examination, she was skull and mandible are less frequent. found to have a bony hard mass over the distal end of the However, although the radiological manifestations left clavicle. It was not tender and measured approximately 6 cm in length. The radiograph (Fig. 4) shows eccentric are now well recognized (Sherman and Soong, 1957), expansion superiorly of the acromial end of the left clavicle. the exact nature of this unusual lesion of bone is still A thin, crescentic cortical rim outlines the lateral half of the poorly understood. The concept of aneurysmal bone mass. On the medial side the cortical margin can no longer be seen. There appears to be some inner texture to the mass cyst as a non-neoplastic lesion, quite different from but no definite honeycombing is seen. Radiographs of the the giant cell tumour, was first introduced by Jaffe rest of the skeleton were unremarkable. Needle biopsy of and Lichtenstein in 1942. Based on two cases only, the mass, immediately prior to operation, revealed benign fibrous tissue with giant cells, consistent with a bone cyst it took more than a decade for its general acceptance. lining. At operation the distal half of the clavicle was Individual papers by Jaffe (1950) and Lichtenstein resected. The surgical specimen (Fig. 5) revealed a mass studded with cysts containing blood. The individual cystic spaces appear larger than in the previous case but the similarity is striking. Histologically the appearances were similar to Case 1. There was more extravasation of blood and the vascular pattern a little more irregular. Fine osteoid formation was noted in several areas. Comment Both radiologist and surgeon felt that the clinical picture and radiographs indicated an aneurysmal bone cyst but because of the age of the patient and the unusual site, a primary tumour of the clavicle such as a chondrosarcoma or a solitary metastasis were thought to be more likely.
•\
FIG. 4. Case 2. Eccentric expanding lesion extending superiorly. Linear shadows suggesting septa are well seen. The cortical rim is lost medially raising the question of malignancy.
I;
FIG. 5. Case 2. Cut surgical specimen showing large spaces containing blood.
707
VOL.
50, No. 598 J. Smith
(1975) claimed that 50% of aneurysmal bone cysts show an underlying primary neoplasm either benign or malignant. Edeiken and Hodes (1973) also found benign and malignant neoplasms associated with aneurysmal bone cyst. Biesecker et al. (1970) found benign bone lesions such as non-ossifying fibroma, chondroblastoma, osteoblastoma and true giant-cell tumour in 30% of cases. However, Tillman et al. (1968) were unable to find any associated neoplasm in 95 cases despite careful scrutiny. Clough and Price (1968) were also clearly sceptical about an association with an underlying neoplasm. We have not seen any association in this institution between malignant neoplasms and aneurysmal bone cyst. This is clearly of considerable therapeutic importance and any cases of aneurysmal bone cyst associated with osteogenic sarcoma or other FIG. 6. Cut section of aneurysmal bone cyst of clavicle in 20-year- malignant tumour deserve to be reported. We do not old patient. The sponge-like appearance is well demon- refer, of course, to telangiectatic osteogenic sarcoma strated. mistakenly diagnosed as aneurysmal bone cyst but a true A.B.C. associated with an underlying malignant (1950) based upon 30 cases led to more general bone tumour. recognition. Prior to this the lesion had been known With regard to associated factors, the first case is under a variety of names. of interest since there was a clear history of trauma In our institution, it has been referred to as sub- and the radiograph strongly suggested an underlying periosteal giant cell tumour (Coley, 1949), and lesion. Since the specimen showed no evidence of atypical giant cell tumour (Coley and Miller, 1942). any other lesion apart from the aneurysmal bone Ewing (1940) referred to it as aneurysmal giant cell cyst, one can only speculate on this. Benign lesions tumour. Many other names have been used (Sher- of the clavicle are uncommon, in particular the giant man and Soong, 1957) but all these earlier authors cell tumour which is excessively rare. If one discards felt that it was related in some way to the giant cell cases reported prior to 1950, and perhaps even a tumour. little later, very few giant cell tumours of the The interior of the lesion consists of multiple clavicle have been recorded, the majority previously vascular channels. In fact, it is not truly a cyst since reported being, in fact, aneurysmal bone cysts. it more closely resembles a sponge (Fig. 6). The walls Lichtenstein (1959) has never seen a true giant cell of the vascular channels may be either thick or thin tumour of the clavicle. It is possible that this was and there may be strips of osteoid tissue or immature simply an unusual simple fracture. trabeculae in the walls. A variable number of benign giant cells may also be found. Blood may be present REFERENCES throughout the cyst or only in part and in long AEGERTER, E. E., and KIRKPATRICK, J. A., 1975. Orthopaedic standing cases it may be simply blood tinged. Diseases, 3rd edn (W. B. Saunders Company, Philadelphia). Lichtenstein (1950) claimed that the underlying BIESECKER, J. L., MARCOVE, R. C , HUVOS, A. G., and abnormality was an arteriovenous communication. MIKE, V., 1970. Aneurysmal bone cysts. Cancer, 26, 615-625. Biesecker et al. (1970) measured pressures within the J. R., and PRICE, C. H. G., 1968. Aneurysmal bone cysts and in three of six patients these were above CLOUGH, cysts. Review of 12 cases. Journal of Bone and Joint the venous pressure. Surgery, 50B, 116-127. Trauma has frequently been mentioned as an COLEV, B. L., and MILLER, L. E., 1942. Atypical giant cell tumor. American Journal of Roentgenology, 47, 541-548. aetiological factor and over 50% of patients give a COLEY, B. L., 1949. Neoplasms of bone and related conditions. history of trauma. In recent years there has been a Their etiology, pathogenesis, diagnosis and treatment (Paul B. Hoeber, Inc., New York). very definite trend suggesting that the aneurysmal DOMINOK, G. W., KNOCH, H. G., MANJA, B., and SCHULZE, bone cyst is a secondary phenomenon and that a K. J., 1971. Die aneurysmatische Knochencyste. Langenvariety of tumours, both benign and malignant, may becks Archievefur Chirurgie, 328, 153-168. be the primary lesion which initiates the arterio- EDEIKEN, J., and HODES, P. J., 1973. Roentgen diagnosis of diseases of bone, 2nd edn, Vol. 2 (The Williams & Wilkins venous communication. Aegerter and Kirkpatrick Company, Baltimore). 708
Aneurysmal bone cyst of clavicle 1959. Bone tumours, 2nd edn, pp. 121 (C. V. Mosby, EWING, J., 1940. Neoplastic diseases. In A treatise on tumors, St. Louis). 4th edn, pp. 323-324 (W. B. Saunders Company, SHERMAN, R. S., and SOONG, K. Y., 1957. Aneurysmal bone Philadelphia). cyst: its roentgen diagnosis. Radiology, 68, 54—64. JAFFE, H. L., and LICHTENSTEIN, L., 1942. Solitary unicameral bone cysts with emphasis on the roentgen picture, SMITH, J., MCLACHIAN, D., HUVOS, A. G., and HIGINBOTHAM, N. L., 1975. Primary tumors of the clavicle and the pathologic appearance and the pathogenesis. Archives scapula. American Journal of Roentgenology, 124, 113-123. of Surgery, 44, 1004-1025. JAFFE, H. L., 1950. Aneurysmal bone cyst. Bulletin of the TILLMAN, B. P., DAHLIN, D. C , LIPSCOMB, P. R., and STEWART, J. R., 1968. Aneurysmal bone cyst: an analysis Hospital for Joint Diseases, 11, 3 - 1 3 . of ninety-five cases. Mayo Clinic Proceedings, 43, 478-495. LICHTENSTEIN, L., 1950. Aneurysmal bone cyst. Cancer, 3, 279-289.
Book review Ultrasonic Encephalography II. By D. N. White, pp. 312,becomes greater in cases of cerebral disease where display of illus., 1976 (Canada, Ultramedison), $35.00. the M echo becomes more difficult than from healthy This book follows seven years after the author's first book persons". The author also states that "Any test that achieves 99.8% accuracy is to be lauded regardless how the on the subject. During that time non-cerebral ultrasound imaging has leapt forward, while encephalography has made accuracy is achieved"; few would agree with this, especially little progress and computerized X-ray tomography is now as the authors published work shows an accuracy rate of only widely available. This book is a broad review of the subject 55%. In the last few years automatic devices have been deveand is intended to explain in non-specialized terms, the severe fundamental physical limitations which have loped in an attempt to improve the reliability of this prevented the development of ultrasound encephalography. technique and these are described in detail in Chapter 7. The acoustic properties of the skull are dealt with in The results obtained with them show no evidence of the detail in the first two chapters while the "characteristics" of anticipated improvement. the midline "M" echo are discussed in Chapter 3. The three The last two chapters discuss a dozen other ultrasound subsequent chapters describe and discuss the use of the techniques which have been applied to cerebral diagnosis conventional video technique and many published series of and, with the exception of the Doppler blood flow studies, results are presented and compared, the false positive rates none seems to have gained clinical acceptance yet. varying from 0.1 to 44% and the false negative rates from This book is a very comprehensive review of the whole 0 to 14%. There is clearly a very high degree of dependance field of cerebral ultrasound and will be of interest to upon operator expertise which the author acknowledges and protagonists of the technique but will also supply antagohe also states "The need for the clinical operator or interpre- nists with much ammunition. tor to use his clinical bias in order to achieve accuracy H. B. MEIRE.
709
![[Aneurysmal bone cyst of the clavicle: about a case].](/assets/img/hold.png)
