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Absence of the Common Carotid Artery in a Patient with a Persistent Trigeminal Artery Variant
79
CASE REPORTS
urethral stricture and urinary incontinence. Since leiomyoma has not been reported to show malignant change [7], follow-up by regular MRI examinations may be suf®cient when the leiomyoma is asymptomatic or when MR ®ndings are similar to those seen in our case. Although the cost of an MRI examination for leiomyoma is high, the patient suffers minimal discomfort and the reproductive organs are not exposed to harmful irradiation. We therefore recommend MRI as a valuable diagnostic tool in the preoperative diagnosis of leiomyoma. REFERENCES 1 Zuckerman IC, Kershner D, Laytner BD, et al. Leiomyoma of the kidney. Ann Surg 1947;126:220±228. 2 Cheng C, Mac-moune Lai F, Chan PSF. Leiomyoma of the female urethra: a case report and review. J Urol 1992;148:1526±1527. 3 BuÈttner. Ein Fall von Myom der Weiblichen Urethra. Z Geburshc GynaÈk 1894;28:136±139.
4 Leidinger RJ, Das S. Leiomyoma of the female urethra. A report of two cases. J Reprod Med 1995;40:229±231. 5 Fry M, Wheeler JS Jr, Mata JA, Culkin DJ, Martin ES, Venable DD. Leiomyoma of the female urethra. J Urol 1988;140:613±614. 6 Lee MC, Lee SD, Kuo HT, Huang TW. Obstructive leiomyoma of the female urethra: report of a case. J Urol 1995;153:420±421. 7 Leung YL, Lee F, Tam PC. Leiomyoma of female utethra causing acute urinary retention and acute renal failure. J Urol 1997;158:1911±1912. 8 Lupetin AR. Female pelvis. In: Stark DD, Bradley WG (eds). Magnetic Resonance Imaging. St. Louis: Mosby, 1988;1281±1282. 9 Hricak H, Chang YCF. The female pelvis. In: Higgins CB, Hrica H (eds). Magnetic Resonance Imaging of the Body. New York: Raven, 1987;414±415. 10 Suzuki K, Hatafuku F, Tamura G, Fujioka T. Retroperitoneal leiomyoma: a case report. Hinyoukika Kiyo 1995;41:995±998. 11 Nakamura M, Tachibana H, Mukaeyama T. A case of leiomyoma of the posterior mediastinum. Nippon Kyoubu Geka Gakkai Zasshi 1996;44:2082±2086. 12 Maya MM, Slywotzky C. Urinary bladder leiomyoma: magnetic resonance imaging ®ndings. Urol Radiol 1992;14:197±199. 13 Cornella JL, Larson TR, Lee RA, Magrina JF, Kammerer-Doak D. Leiomyoma of the female urethra and bladder: report of twenty-three patients and review of the literature. Am J Obstet Gynecol 1997;176: 1278±1285.
doi:10.1053/crad.1999.0276, available online at http://www.idealibrary.com on
Absence of the Common Carotid Artery in a Patient with a Persistent Trigeminal Artery Variant SANDRO ROSSITTI, RAILI RAININKO Department of Diagnostic Radiology, Uppsala University Hospital, S-751 85 Uppsala, Sweden
We found the present case when retrospectively reviewing the ®les of patients with intracranial aneurysm in our institution. It concerns the coexistence of a rare developmental anomaly of the aortic arch vessels and a persistent carotid-vertebrobasilar communication variant. Since no common embryologic basis is known, this association was probably fortuitous. Each of these particular anomalies can pose unique diagnostic and therapeutic dif®culties.
right posterior communicating artery of the foetal type. Left vertebral angiography demonstrated a rudimentary left PICA and absence of the left AICA (Fig. 3). Right vertebral angiography showed segmental hypoplasia of the right vertebral artery between the origin of the right PICA and the basilar artery (not shown). The ®ndings of clinical interest were two saccular aneurysms unrelated to the anomalous vessels, localized respectively in the right carotid syphon (not shown) and at the origin of the left superior cerebellar artery (SCA) from the basilar artery (Fig. 3).
DISCUSSION CASE REPORT A 40-year-old woman with subarachnoid haemorrhage was examined with transfemoral cut-®lm cerebral angiography. Due to dif®culty in catheterizing the left internal carotid artery (ICA), this vessel was examined after performing aortography. The common carotid artery (CCA) was absent on the left side, where the ICA and the external carotid artery (ECA) originated separately from the aortic arch (Fig. 1). A persistent primitive trigeminal artery variant (PTAV) arose from the left ICA (Fig. 2). This anomalous vessel supplied the vascular territory of the left anterior inferior cerebellar artery (AICA) and most of the territory of the left posterior inferior cebebellar artery (PICA). The carotid angiograms showed also hypoplasia of the segment A1 of the left anterior cerebral artery, and a Author for correspondence: Sandro Rossitti, MD, PhD, Department of Diagnostic Radiology, Uppsala University Hospital, S-751 85 Uppsala, Sweden. Fax: 46 18 510865.
Absence of the common carotid artery, with separate origins of the ECA and ICA from the aortic arch, is unusual. In the few reported cases [1±5] this was often associated with major vascular anomalies such as cervical aortic arch, double aortic arch, right aortic arch and aberrant right subclavian artery, and there was no side preference. Association with a persistent proatlantal intersegmental artery was observed in only one case (Gottschau, 1885; cited by Lie [1]). The condition probably occurs due to persistence of the carotid duct between the third and the fourth aortic arches, or alternatively due to regression of the fourth aortic arch, the role of which would be taken over by the third aortic arch. This anomaly is asymptomatic unless associated with other conditions, however, it may have some practical consequences. Absence of the CCA should be kept in
80
CLINICAL RADIOLOGY
Fig. 1 ± Arch aortogram. 1, innominate artery; 2, right common carotid artery; 3, right subclavian artery; 4, right vertebral artery; 5, left external carotid artery; 6, left internal carotid artery; 7, left subclavian artery; 8, left vertebral artery. In order to achieve a better anatomical presentation the right and left sides of this image were digitally composed from two sequential images of the original cut-®lm angiography series.
mind when an additional vessel is seen arising from the aortic arch on aortography. It may cause technical dif®culties in performing direct percutaneous carotid angiography in the rare cases that it is indicated (e.g., in interventional neuroangiography as an alternative to the transfemoral route in special cases). The interpretation of ultrasound examinations of the cervical arteries would be very dif®cult when this anomaly is present. Similar dif®culties would probably occur in the case of a intrathoracic bifurcation of the CCA, which is also relatively uncommon. In the present case this anomaly made selective catheterization of the ipsilateral ICA dif®cult
Fig. 2 ± Localized views of left internal carotid angiogram on lateral (a) and left oblique (b) projections. 1, internal carotid artery; 2, persistent PTAV supplying the vascular territory of the left anterior inferior cerebellar artery and most of the territory of the left posterior inferior cebebellar artery; 3, hypoplastic left anterior cerebral artery (segment A1); 4, left pericallosal artery; and 5, left middle cerebral artery, with ordinary calibre and branching.
81
CASE REPORTS
until an aortography was carried out to determine the origin of the arch vessels. Naturally, this anomaly could also pass unnoticed using either catheterization or direct puncture if it was assumed that the catheter tip or needle point was introduced in the ICA above a normal CCA bifurcation. The internal carotid artery origin of cerebellar arteries via a persistent trigeminal artery variant (PTAV) is another anomaly that was also present in the same patient. Persistent trigeminal artery variant is a cerebellar artery arising directly from the precavernous portion of the ICA. It is a result of the persistence of a primitive trigeminal artery associated with an incomplete fusion of the longitudinal neural arteries (i.e., the embryonal arteries that form the basilar artery) [6]. It may have distributions corresponding to the SCA, to the AICA or to the PICA territories. The corresponding artery of vertebrobasilar origin may be hypoplastic or absent depending on the calibre of the PTAV. In the present case, the PTAV supplied the ipsilateral AICA and most of the PICA territories. These arteries were found to be absent and hypoplastic, respectively. The practical consequences of the presence of a PTAV are related to potential paradoxical embolic lesions of the cerebellum during diagnostic or interventional neuroangiography, as well as to the risk of ischaemic or haemorrhagic complications during percutaneous Gasserian ganglion procedures. REFERENCES
Fig. 3 ± Left vertebral angiogram. 1, rudimentary left anterior inferior cerebellar artery; 2, right anterior inferior cerebellar artery (note absence of a left anterior inferior cerebellar artery); 3, small aneurysm arising from the basilar artery at the origin of the left superior cerebellar artery; 4, left posterior cerebral artery with ordinary calibre and branching; 5, right posterior cerebral artery with incomplete demonstration of its peripheral branches, which were supplied mainly by a right posterior communicating artery of the foetal type (not shown).
1 Lie TA. Congenital Anomalies of the Carotid Arteries. Amsterdam: Excepta Medica Foundation, 1968. 2 Andrews ET, Howard JM. Congenital anomalies of the carotid artery: a case report. J Amer Geriat Soc 1963;11:642±646. 3 Haughton VM, Rosenbaum AE. The normal and anomalous aortic arch and brachiocephalic arteries. In: Newton TH, Potts DG (eds). Radiology of the Skull and Brain, Vol. 2. St Louis: Mosby, 1974;1145±1163. 4 Bryan RN, Drewyer RG, Gee W. Separate origins of the left internal and external carotid arteries from the aorta. Am J Roentgenol 1978;130:362± 365. 5 Moore TS, Morris JL. Aortic arch vessel anomalies associated with persistent trigeminal artery. Am J Roentgenol 1979;133:309±311. 6 Siqueira M, Piske R, Ono M, Marino-Junior R. Cerebellar arteries originating from the internal carotid artery. Am J Neuroradiol 1993;14: 1229±1235.
CASE REPORTS
urethral stricture and urinary incontinence. Since leiomyoma has not been reported to show malignant change [7], follow-up by regular MRI examinations may be suf®cient when the leiomyoma is asymptomatic or when MR ®ndings are similar to those seen in our case. Although the cost of an MRI examination for leiomyoma is high, the patient suffers minimal discomfort and the reproductive organs are not exposed to harmful irradiation. We therefore recommend MRI as a valuable diagnostic tool in the preoperative diagnosis of leiomyoma. REFERENCES 1 Zuckerman IC, Kershner D, Laytner BD, et al. Leiomyoma of the kidney. Ann Surg 1947;126:220±228. 2 Cheng C, Mac-moune Lai F, Chan PSF. Leiomyoma of the female urethra: a case report and review. J Urol 1992;148:1526±1527. 3 BuÈttner. Ein Fall von Myom der Weiblichen Urethra. Z Geburshc GynaÈk 1894;28:136±139.
4 Leidinger RJ, Das S. Leiomyoma of the female urethra. A report of two cases. J Reprod Med 1995;40:229±231. 5 Fry M, Wheeler JS Jr, Mata JA, Culkin DJ, Martin ES, Venable DD. Leiomyoma of the female urethra. J Urol 1988;140:613±614. 6 Lee MC, Lee SD, Kuo HT, Huang TW. Obstructive leiomyoma of the female urethra: report of a case. J Urol 1995;153:420±421. 7 Leung YL, Lee F, Tam PC. Leiomyoma of female utethra causing acute urinary retention and acute renal failure. J Urol 1997;158:1911±1912. 8 Lupetin AR. Female pelvis. In: Stark DD, Bradley WG (eds). Magnetic Resonance Imaging. St. Louis: Mosby, 1988;1281±1282. 9 Hricak H, Chang YCF. The female pelvis. In: Higgins CB, Hrica H (eds). Magnetic Resonance Imaging of the Body. New York: Raven, 1987;414±415. 10 Suzuki K, Hatafuku F, Tamura G, Fujioka T. Retroperitoneal leiomyoma: a case report. Hinyoukika Kiyo 1995;41:995±998. 11 Nakamura M, Tachibana H, Mukaeyama T. A case of leiomyoma of the posterior mediastinum. Nippon Kyoubu Geka Gakkai Zasshi 1996;44:2082±2086. 12 Maya MM, Slywotzky C. Urinary bladder leiomyoma: magnetic resonance imaging ®ndings. Urol Radiol 1992;14:197±199. 13 Cornella JL, Larson TR, Lee RA, Magrina JF, Kammerer-Doak D. Leiomyoma of the female urethra and bladder: report of twenty-three patients and review of the literature. Am J Obstet Gynecol 1997;176: 1278±1285.
doi:10.1053/crad.1999.0276, available online at http://www.idealibrary.com on
Absence of the Common Carotid Artery in a Patient with a Persistent Trigeminal Artery Variant SANDRO ROSSITTI, RAILI RAININKO Department of Diagnostic Radiology, Uppsala University Hospital, S-751 85 Uppsala, Sweden
We found the present case when retrospectively reviewing the ®les of patients with intracranial aneurysm in our institution. It concerns the coexistence of a rare developmental anomaly of the aortic arch vessels and a persistent carotid-vertebrobasilar communication variant. Since no common embryologic basis is known, this association was probably fortuitous. Each of these particular anomalies can pose unique diagnostic and therapeutic dif®culties.
right posterior communicating artery of the foetal type. Left vertebral angiography demonstrated a rudimentary left PICA and absence of the left AICA (Fig. 3). Right vertebral angiography showed segmental hypoplasia of the right vertebral artery between the origin of the right PICA and the basilar artery (not shown). The ®ndings of clinical interest were two saccular aneurysms unrelated to the anomalous vessels, localized respectively in the right carotid syphon (not shown) and at the origin of the left superior cerebellar artery (SCA) from the basilar artery (Fig. 3).
DISCUSSION CASE REPORT A 40-year-old woman with subarachnoid haemorrhage was examined with transfemoral cut-®lm cerebral angiography. Due to dif®culty in catheterizing the left internal carotid artery (ICA), this vessel was examined after performing aortography. The common carotid artery (CCA) was absent on the left side, where the ICA and the external carotid artery (ECA) originated separately from the aortic arch (Fig. 1). A persistent primitive trigeminal artery variant (PTAV) arose from the left ICA (Fig. 2). This anomalous vessel supplied the vascular territory of the left anterior inferior cerebellar artery (AICA) and most of the territory of the left posterior inferior cebebellar artery (PICA). The carotid angiograms showed also hypoplasia of the segment A1 of the left anterior cerebral artery, and a Author for correspondence: Sandro Rossitti, MD, PhD, Department of Diagnostic Radiology, Uppsala University Hospital, S-751 85 Uppsala, Sweden. Fax: 46 18 510865.
Absence of the common carotid artery, with separate origins of the ECA and ICA from the aortic arch, is unusual. In the few reported cases [1±5] this was often associated with major vascular anomalies such as cervical aortic arch, double aortic arch, right aortic arch and aberrant right subclavian artery, and there was no side preference. Association with a persistent proatlantal intersegmental artery was observed in only one case (Gottschau, 1885; cited by Lie [1]). The condition probably occurs due to persistence of the carotid duct between the third and the fourth aortic arches, or alternatively due to regression of the fourth aortic arch, the role of which would be taken over by the third aortic arch. This anomaly is asymptomatic unless associated with other conditions, however, it may have some practical consequences. Absence of the CCA should be kept in
80
CLINICAL RADIOLOGY
Fig. 1 ± Arch aortogram. 1, innominate artery; 2, right common carotid artery; 3, right subclavian artery; 4, right vertebral artery; 5, left external carotid artery; 6, left internal carotid artery; 7, left subclavian artery; 8, left vertebral artery. In order to achieve a better anatomical presentation the right and left sides of this image were digitally composed from two sequential images of the original cut-®lm angiography series.
mind when an additional vessel is seen arising from the aortic arch on aortography. It may cause technical dif®culties in performing direct percutaneous carotid angiography in the rare cases that it is indicated (e.g., in interventional neuroangiography as an alternative to the transfemoral route in special cases). The interpretation of ultrasound examinations of the cervical arteries would be very dif®cult when this anomaly is present. Similar dif®culties would probably occur in the case of a intrathoracic bifurcation of the CCA, which is also relatively uncommon. In the present case this anomaly made selective catheterization of the ipsilateral ICA dif®cult
Fig. 2 ± Localized views of left internal carotid angiogram on lateral (a) and left oblique (b) projections. 1, internal carotid artery; 2, persistent PTAV supplying the vascular territory of the left anterior inferior cerebellar artery and most of the territory of the left posterior inferior cebebellar artery; 3, hypoplastic left anterior cerebral artery (segment A1); 4, left pericallosal artery; and 5, left middle cerebral artery, with ordinary calibre and branching.
81
CASE REPORTS
until an aortography was carried out to determine the origin of the arch vessels. Naturally, this anomaly could also pass unnoticed using either catheterization or direct puncture if it was assumed that the catheter tip or needle point was introduced in the ICA above a normal CCA bifurcation. The internal carotid artery origin of cerebellar arteries via a persistent trigeminal artery variant (PTAV) is another anomaly that was also present in the same patient. Persistent trigeminal artery variant is a cerebellar artery arising directly from the precavernous portion of the ICA. It is a result of the persistence of a primitive trigeminal artery associated with an incomplete fusion of the longitudinal neural arteries (i.e., the embryonal arteries that form the basilar artery) [6]. It may have distributions corresponding to the SCA, to the AICA or to the PICA territories. The corresponding artery of vertebrobasilar origin may be hypoplastic or absent depending on the calibre of the PTAV. In the present case, the PTAV supplied the ipsilateral AICA and most of the PICA territories. These arteries were found to be absent and hypoplastic, respectively. The practical consequences of the presence of a PTAV are related to potential paradoxical embolic lesions of the cerebellum during diagnostic or interventional neuroangiography, as well as to the risk of ischaemic or haemorrhagic complications during percutaneous Gasserian ganglion procedures. REFERENCES
Fig. 3 ± Left vertebral angiogram. 1, rudimentary left anterior inferior cerebellar artery; 2, right anterior inferior cerebellar artery (note absence of a left anterior inferior cerebellar artery); 3, small aneurysm arising from the basilar artery at the origin of the left superior cerebellar artery; 4, left posterior cerebral artery with ordinary calibre and branching; 5, right posterior cerebral artery with incomplete demonstration of its peripheral branches, which were supplied mainly by a right posterior communicating artery of the foetal type (not shown).
1 Lie TA. Congenital Anomalies of the Carotid Arteries. Amsterdam: Excepta Medica Foundation, 1968. 2 Andrews ET, Howard JM. Congenital anomalies of the carotid artery: a case report. J Amer Geriat Soc 1963;11:642±646. 3 Haughton VM, Rosenbaum AE. The normal and anomalous aortic arch and brachiocephalic arteries. In: Newton TH, Potts DG (eds). Radiology of the Skull and Brain, Vol. 2. St Louis: Mosby, 1974;1145±1163. 4 Bryan RN, Drewyer RG, Gee W. Separate origins of the left internal and external carotid arteries from the aorta. Am J Roentgenol 1978;130:362± 365. 5 Moore TS, Morris JL. Aortic arch vessel anomalies associated with persistent trigeminal artery. Am J Roentgenol 1979;133:309±311. 6 Siqueira M, Piske R, Ono M, Marino-Junior R. Cerebellar arteries originating from the internal carotid artery. Am J Neuroradiol 1993;14: 1229±1235.