Coincidental aneurysms with tumours of pituitary origin

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Journal ofneurology, Neurosurgery, and Psychiatry, 1978, 41, 972-979 Coincidental aneurysms with tumours of pituitary origin JAN JAKUBOWSKI AND BRIAN KENDALL From the Gough Cooper Department of Neurological Surgery, Lysholm Radiological Department, The National Hospital for Nervous Diseases, Queen Square, and the Neurosurgical and Radiological Departments, The Middlesex Hospital, London SUMMARY Angiographic studies on 150 pituitary adenomas and 33 craniopharyngiomas presenting for surgical treatment are reviewed. Eleven incidental silent aneurysms (four arising from the intracavernous and four from the supraclinoid carotid artery, and three from the anterior cerebral artery complex) are shown. Intracavernous aneurysms were also present in two acromegalic patients who had been treated previously with yttrium implantation. Although encasement of vessels by these tumours is unusual, the relevance of vascular abnormalities to surgical treatment is sufficient to justify routine magnification angiography. The occurrence of "silent" intracranial aneurysms is well documented. Housepian and Pool (1958), in a detailed study of the cerebral arteries in 5762 necropsy cases collected between 1914 and 1956, found 32 (0.56%) with aneurysms which had remained clinically silent. Du Boulay (1965) analysed carotid angiograms performed for tumour and vascular disease in 2595 cases and found silent aneurysms in 0.27%. However, only 27% of the angiograms were bilateral, and the vertebrobasilar circulation was not outlined. Allowing for incomplete angiography, the incidence in the two studies is comparable. Silent intracranial aneurysms located distant from the lesion to be treated have little relevance to surgical management of most patients. However, aneurysms of the major arteries adjacent to pituitary and suprasellar tumours are an additional hazard to surgical treatment. Previous knowledge of the presence and anatomy of such aneurysms is important during separation of the tumour capsule from the major vessels, or removal of an intracavernous extension of a tumour lying close to the carotid artery. Giant aneurysms in the parasellar region presenting clinically as pituitary tumours are well Address for reprint requests: Mr J. Jakubowski, Department of Neurosurgical Studies, The National Hospital, Queen Square, London WCIN 3BG. Accepted 26 May 1978 recognised (Mitchell, 1889; Cushing, 1912; Jefferson, 1937; White and Ballantine, 1961; Raymond and Tew, 1978) but silent aneurysms associated with symptomatic pituitary and suprasellar tumours have not received so much attention. Two cases are referred to by Hankinson and Banna (1976), and they, and also Ambrose (1973), consider that one important reason for routine angiography on these tumours is to show incidental aneurysms: individual cases are described by Cushing (1912), Love (1963), Lippman et al. (1971) and von Alphen (1975), and illustrated by Gado and Bull (1971). In general, the tumours are diagnosed clinically, confirmed by plain skull radiographs and their intracranial extension is assessed by pneumoencephalography. More recently, computed tomograms with coronal and axial sections have given considerable information on the extent and composition of these lesions, but many surgeons still prefer pneumoencephalograms to assess the relationship of the optic chiasm and nerves before a transcranial approach. In many neurosurgical units angiography is not performed unless the nature of the lesion is uncertain, especially if giant aneurysm or meningioma is suspected. The necessity of the procedure to show the precise relationships of vessels to masses in the pituitary region is debatable, but the use of magnification angiography for this purpose has revealed unsuspected vascular abnormalities with sufficient frequency to merit discussion. 972

Coincidental aneurysms with tumours of pituitary origin Patients and methods We reviewed all proven cases of pituitary adenoma and craniopharyngioma presenting to the Department of Neurosurgical Studies at The National Hospital for Nervous Diseases between 1968 and 1978 and to the Middlesex Hospital between 1975 and 1978, in which angiograms were available. The clinical features, tumour size, and angiographic abnormalities, including the presence and distribution of aneurysms, and the findings and results of surgery were noted. Results There were 183 cases-150 pituitary adenomas and 33 craniopharyngiomas. The histological diagnosis, age and sex distribution, and percentage of aneurysms are shown in Table 1, and general angiographic findings in Table 2. The cases referred for surgery in The National Hospital all had visual failure, caused by a moderate or large suprasellar extension. Many Middlesex Hospital patients presented with endocrine problems alone, but angiography was not performed in patients selected for a trans-sphenoid hypophysectomy, which included all cases with a tumour confined to the sella turcica or with only minor suprasellar extension. Nearly all the angiograms were performed to show vascular anatomy adjacent to a moderate or large suprasellar extension. Occasionally there was clinical doubt about the type of tumour, and angiography was carried out to elucidate. In one hypertensive acromegalic (case 2), a pneumoencephalogram showed only 5 mm suprasellar extension of the tumour, but it Table 1 Statistical analysis of presented cases revealed a small mass suggesting an aneurysm (Fig. 1). An angiogram was performed specifically to confirm this and to exclude other aneurysms. In another acromegalic patient (case 12) who had been previously treated with yttrium implants, pain over the left eye was a prominent symptom, and raised the possibility of intracavernous aneurysm which was confirmed by angiography. Only one other patient had been treated previously, and in no other case were there any symptoms specifically suggestive of aneurysm. The relevant features of the 11 cases with incidental aneurysms are set out in Table 3, and the distribution of aneurysms is shown in Fig. 2. Their clinical presentation was similar to that of the patients without aneurysms. Only one patient (case 2) was hypertensive. In six cases the aneurysm was well seen at surgery, and the angiographic data were considered significant to the safety of the procedure, but only one aneurysm (case 10) was treated. In the other patients, knowledge of the aneurysm was taken into account in surgical planning. Two patients suffering from active acromegaly despite previous yttrium implants had aneurysmal dilatation of the cavernous segment of one carotid artery (Fig. 3). These aneurysms were considered more likely to be caused by the implant surgery rather than spontaneous, and are, therefore, not included in Table 3. Discussion The value of cerebral angiography combined with plain radiographs in the aetiological diagnosis of suprasellar tumours is universally accepted. Number Mean age (SD) Sex Aneurysm (yr) F M Chromophobe adenoma 117 48.5 (10.3) 50 67 6 ( 5.1%) -------- ** P<0.005 Eosinophilic or mixed adenoma 29 46.7 (11.4) 13 16 4 (13.8%)+2*=6 (20.7") - Basophilic adenoma 4 45 (8.6) 3 1 - Craniopharyngioma 33 43 (15.1) 13 10 1 *Associated with previous yttrium implantation. **x test. Table 2 General angiographic findings Vessels Displaced Narrowed Occluded Aneurysms Intracavernous and/or supraclinoid carotid 148 (81 %) 10 (5.4%) 1 10* (5.4 ) Anterior cerebral 128 (70.3%) 3 (1.6%) - 3 (1.6%,) Middle cerebral 5 (2.7 %) - - 0 *Two associated with previous yttrium implantation. 973

974 Table 3 Clinical and radiological features and operative findings of cases presented Jan Jakubowski and Brian Kendall Patient Histology Clinical picture Radiologicalfindings Site and description of Surgery aneurysm Case 1 Eosinophilic adenoma Visual failure Large eroded sella L. ophthalmic junction Radical removal PP 3 years; 10 mm suprasellar 5 mm diameter, projecting of the tumour. F 36 yr amenorrhea 1 year; extension, elevated superiorly. Aneurysm seen acromegaly. chiasmatic recess. and avoided. L. ACA elevated. L. ICA displaced laterally. Case 2 Eosinophilic adenoma Sella expanded and Anterior communicating Trans-sphenoid. PJ eroded, mass in sphenoid 10 mm diameter, M 57 yr sinus 5 mm suprasellar projecting inferiorly. extension. Fig. 1 Case 3 EE M45yr Case 4 Cw M 64 yr Case 5 FM F 46 yr Case 6 LC M 47 yr Mixed adenoma Eosinophilic adenoma Chromophobe adenoma Chromophobe adenoma Acromegaly 5 years; hypertension 5 years; headache 5 years; BP 180/1 10 mmhg. Carpal tunnel syn. 1 year; galactorrhoea on/ off; mild acromegaly; visual deficits. Eroded sella 25 mm lobulated extension third ventricle elevated. ICA displaced laterally. L. ACA elevated, R. ACA absent. Acromegaly 10 Large sella, destroyed years; floor, 15 mm supraheadache 1 year. sellar extension. L. ICA displaced laterally. Visual failure 8 months; headache 10 years. Hypopituitarism 2 years; visual failure 2 months. Destruction of sella 30 mm suprasellar extension, third ventricle indented. Cavernous and supraclinoid ICA displaced laterally. ACA elevated. Enlarged eroded sella 25 mm suprasellar extension, third ventricle indented. L. cavernous carotid lat. R. carotid occluded. L. cavernous carotid artery 4 mm diameter projecting inferiorly. Fig. 4 R. intracavernous carotid artery, 5 mm diameter, projecting medially and anteriorly. R. ophthalmic junction 4 mm diameter projecting medially. Fig. 5 L. anterior cerebral 3 mm diameter. Projecting superiorly. Fig. 6 Partial removal of the tumour. Aneurysm not seen. Small part of L. cavernous sinus extension was left in situ. Radical removal of the tumour. Aneurysm not seen. Radical removal of the tumour. Aneurysm not seen. Partial removal of tumour. Aneurysm not seen, part of tumour eroding cavernous sinus left in situ. Fig. 1 Case 2. Pneumoencephalogram: erect lateral tomogram. Slight suprasellar extension of pituitary tumour (long arrows). Slightly lobulated anterior communicating aneurysm (arrow heads). Anterior cerebral arteries indicated by short arrows. J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.41.11.972 on 1 November 1978. Downloaded from http://jnnp.bmj.com/ on 28 March 2019 by

Coincidental aneurvsms with tumours of pituitary origin Table 3 Clinical and radiological features and operative findings of cases presented (continued) Patient Histology Clinical picture Radiologicalfindings Site and description of Sutrgery aneurysm Case 7 Chromophobe adenoma Visual failure Large eroded sella R. distal carotid Partial removal EH 18 months; 25 mm suprasellar artery 8 mm diameter of the tumour. M 53 yr hypopituitary extension. Anterior part projecting superiorly Aneurysm seen, syndrome. of third ventricle and anteriorly. capsule indented ACA Fig. 7 attached to elevated (L. hypoplastic). aneurysm left ICA displaced in situ. laterally. Case 8 Chromophobe adenoma Hypopituitarism Sella expanded. 20 mm R. intracavernous 3 mm Radical removal EL 11 years; suprasellar extension. diameter, projecting of the tumour. M 56 yr visual failure Cavernous ICA laterally. Aneurysm not. I year. displaced laterally seen. ACA elevated. Case 9 Chromophobe adenoma Visual failure Large expanded sella R. carotid artery Radical removal CD 2 years; 10 mm posterior origin of posterior of the tumour. F 57 yr hypopituitarism suprasellar extension communicating artery Aneurysm seen in 3 months. post-fixed chiasma. 4 mm diameter in contact with R. cavernous ICA projecting inferiorly. tumour. Small displaced laterally. ACA elevated. piece of capsule attached to the aneurysm was left in situ. Case 10 Chromophobe adenoma Visual failure Enlarged eroded sella R. anterior cerebral Partial removal WL 18 months; 10 mm suprasellar artery 12 mm diameter, of tumour. F 62 yr headache 18 extension, lobulated. multilocular projecting Aneurysm seen in months; Chiasmatic recess posteriorly perforating contact with hypopituitarism. elevated. Aneurysmal arteries close to neck. tumour. Proximal mass seen. ACA Fig. 8 R. ACA clipped. elevated. ICA displaced laterally. Case 11 Craniopharyngioma Hypopituitarism Large eroded sella R. intracavernous Partial removal is 8 years; 30 mm suprasellar carotid artery, 7 mm of the tumour. M 38 yr visual failure extension, third diameter projecting Aneurysm not 6 months. ventricle indented. medially. seen. Cavernous ICA displaced Fig. 9 laterally. ACA elevated. Once a specific diagnosis has been established, the degree of intracranial extension and the relationship of neural structures can generally be determined more precisely by pneumoencephalography and computed tomography than by angiography, though in our selected series only 5.5% of the angiograms failed to show displacement of vessels caused by the tumour extension. It is rare for arteries to be enclosed within the tumour, and vessel displacement can usually be predicted from the extent of a mass shown on the other studies. In only one case in this whole series was an artery definitely narrowed, and in another occluded (Fig. 6) by encasement in the tumour. Considerable narrowing of the intracavernous carotid artery occurred in another patient, but it was probably part of more generalised atheroma. In the patient with carotid artery occlusion (case 6), collateral circulation through the meninges adjacent to the tumour was shown on the angiogram, and demonstration of these vessels may have a significant bearing on surgery in rare cases. It is the previous knowledge of incidental aneurysms which we consider to be of greater importance since this may allow planned modification of surgical approach to avoid damaging them or to include their treatment. The high frequency of aneurysms demonstrated in this series may be due partly to angiographic technique. In 80% of the cases bilateral carotid angiography was performed, and in the other 20% good cross flow was obtained, usually with reflux Middle cerebral artery An,ter,or cerebral artery go Dost comimunicatingq artery _ K x 0 t Ophthalmic artery ) t Intra cav,ernous carotid 0 t Fig. 2 Diagram indicating position of aneurysms. Numerals refer to case numbers (see text). 975

976 Jan Jakubowski and Brian Kendall :.~ ~~~~~~~~~~~.........v....., :..:: ~ ~ ~ ~ ~ ~ ~~~~~~~~~~~ ~..... ja.,~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~... Fig. 3 prints: (a) lateral, (b) antero-posterior projection. Theia Case 12. Left carotid angiogramn subtractionx yttrium implants are visible in contact with mediallya projecting aneurysmal dilatation of cavernous segment of internal carotid artery. ~.;............ Fig. Case.3.Left..oi niga,ltrlpoecin nrcvrosaers (arrow heads) projecting inferiorly and slightly medially, on~~~~~~~~~~~~~... partially superimposed carotid~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~; J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.41.11.972 on 1 November 1978. Downloaded from http://jnnp.bmj.com/ on 28 March 2019 by

Coincidental aneurysms with tumours of pituitary origin Fig. 5 Case 5. Right carotid angiogram, subtraction print antero-posterior projection. The intracavernous and supraclinoid segments of the internal carotid artery are displaced laterally. The anterior cerebral artery is elevated. There is an unilocular aneurysm projecting superiorly and medially from the supraclinoid carotid, at the origin of the ophthalmic artery. f(i{ (a... Fig. 6 Case 6. Right common carotid aizgiogram subtraction print, lateral projection. (a) The internal carotid artery is occluded. There is filling of the cavernous carotid artery (short arrows) through meningeal branches of the ascending pharyngeal artery (crossed arrow), middle meningeal artery (long arrow) and artery of foramen rotundum (arrow heads). (b) Tumour blush is shown around the cavernous carotid artery. (c) Left carotid angiogram subtraction print, antero-posterior projection. The cavernous segment is displaced laterally. There is a small anterior cerebral aneurysm (arrow head). 6(1)) (1) 6(r)... 977

978 Jan Jakubowski and Brian Kendall Fig. 7 Case 7. Right internal carotid angiogram subtraction print lateral projection. Distal carotid aneurysm projecting anteriorly and superiorly (arrow head). Fig. 8 Case 10. Right carotid angiogram antero-posterior projection with cross compression. Lateral displacement of both supraclinoid segments and elevation of anterior cerebral arteries. Multilocular right anterior cerebral aneurysm projecting superiorly and posteriorly. down the contralateral artery, so that angiography was generally complete. Though all the aneurysms were larger than 3 mm in diameter and could have been shown by conventional methods, magnification was routine. Radiographic subtraction was performed as indicated. Angiograms had not been performed previously in the two cases with aneurysms adjacent to yttrium implants, so that it is not possible to be sure whether these aneurysms were incidental, post-traumatic, or associated with the radiation in the immediate proximity. It is probable that a majority of these aneurysms were traumatic but the incidence of this complication is unknown because of lack of previous angiographic studies of these cases. However, cavernous sinus syndromes and fistulas have not been noted after pituitary implants so that progressive growth

Coincidental aneurysms with tumours of pituitary origin Fig. 9 Case 11. Right carotid angiogram, oblique projection, subtraction print. A wide-necked intracavernous aneurysm is shown projecting medially (arrow heads). and rupture of any complicating aneurysms must be rare. The demonstration of two such aneurysms in our sample suggests that angiography should certainly be performed before implantation or subsequent surgery in the region of implants. The intracavernous segments of the carotid arteries may encroach up to the midline. Their anatomy should be determined before pituitary implantation. The reason for the higher frequency of aneurysms in association with these tumours than that of incidental aneurysms previously recorded is unknown. There were no obvious clinical differences between these cases and the rest of our series, and, apart from case 2 previously mentioned. there was no evidence of diffuse vascular disease or hypertension. With the exception of the anterior communicating aneurysm in case 2, the aneurysms were all on vessels adjacent to the tumours. This suggests the possibility of a mechanical effect, perhaps associated with increased tension on or flow through small vessels supplying the tumour. There was, however, no obvious difference in the vascularity of the tumours with aneurysms and that of the rest of our cases. A relationship between acromegaly and vascular disease is established, and the proportion of aneurysms was much greater in our cases with acromegaly. It may be that abnormal pituitary g.4 hormone levels, which were present in all our cases, affect the arterial walls and predispose to aneurysm formation. We wish to thank Mr John Andrew, Consultant Neurosurgeon at The Middlesex Hospital, London, and Professor Lindsay Symon of The National Hospital, Queen Square and Maida Vale, for their helpful criticism of the paper. References 979 Alphen, von H. A. M. (1975). Microsurgical frontotemporal approach to pituitary adenomas with extrasellar extension. Clinical Neurology and Neurosurgery, 78, 247-256. Ambrose, J. (1973). Radiological diagnosis of pituitary tumours. In Pituitary Tumours, pp. 79-121. Edited by J. S. Jenkins. Butterworths: London. Cushing, H. (1912). The Pituitary Body and its Disorders. Clinical states produced by disorders of the hypophysis cerebri. J. B. Lippincott: Philadelphia. Du Boulay, G. H. (1965). Some observations on the natural history of intracranial aneurysms. British Journal of Radiology, 38, 721-757. Gado, M., and Bull, J. W. D. (1971). The carotid angiogram in suprasellar masses. Neuroradiology, 2, 136-153. Hankinson, J., and Banna, M. (1976). Pituitary and Parapituitary Tumours. W. B. Saunders: Eastbourne. Housepian, E. M., and Pool, J. L. (1958). A systematic analysis of intracranial aneurysms from the autopsy file of the Presbyterian Hospital 1914-1956. Journal of Neuropathology and Experimental Neurology, 17, 409-423. Jefferson, G. (1937). Compression of the chiasma, optic nerves and optic tracts by intracranial aneurysms. Brain, 60, 444-497. Lippman, H. H., Onotrio, B. M., and Baker, H. L. (1971). Intrasellar aneuryem and pituitary adenoma: report of a case. Proceedings of the Mayo Clinic, 46, 532-535. Love, J. G. (1963). Association of carotid aneurysm with neoplasm compressing the optic chiasm. Proceedings of the Staff Meetings of the Mayo Clinic, 38, 156-161. Mitchell, S. W. (1889). Aneurysm of an anomalous artery causing antero-posterior division of the chiasma of the optic nerves and producing bitemporal hemianopia. Journal of Nervous and Mental Disease, 14, 14-62. Raymond, L. A., and Tew, J. (1978). Large suprasellar aneurysms imitating pituitary tumour. Journal of Neurology, Neurosurgery, and Psychiatry, 41, 83-87. White, J. C., and Ballantine, H. (1%91). Intrasellar aneurysms simulating hypophyseal tumors. Journal of Neurosurgery, 18, 34-50.