Eur J Vasc Surg 6, 668-672(1992)
CASE REPORT
Fibromuscular Dysplasia of Visceral Arteries R. L. Insall 1, J. Chamberlain 1 and H. W. C. Loose 2 Departments of 1Surgery and 2Radiology, Freeman Hospital, High Heaton, Newcastle upon Tyne, NE7 7DN, U.K. The case histories of two patients with combined renal and extra-renal fibromuscular dysplasia are presented. Readers are reminded of this rare but important condition as a cause of obscure abdominal symptoms and abdominal bleeding in the absence of atherosclerotic aortic aneurysm. The aetiology, histology, and management of the condition are discussed. Key Words: Fibromuscular dysplasia; Extra-renal; Visceral arteries.
Introduction
Fibromuscular dysplasia is a rare, non-atherosclerotic condition affecting large and medium-sized arteries. Initially recognised in patients with reno-vascular hypertension, 1 the condition has subsequently been found to affect splanchnic and iliac arteries, 2-4 aorta, intra- and extra-cranial, and axillo-brachial arteries.S" 6 Patients may present with occlusive disease 7 or with aneurysmal disease prone to dissection or rupture. 6'8-1~ In common with other aneurysmal disease, rupture carries a high mortality rate (approximately 80%) and occurs in 5-10% of cases. 11 Extra-renal fibromuscular dysplasia is rarely found without renal artery involvement and is most often seen as an incidental finding during angiographic investigation of reno-vascular hypertension, it is present in around 5% of patients with renal fibromuscular dysplasia. 12 At variance with atherosclerosis, the condition predominantly affects fertile w o m e n in the middle third of life. 13 This paper presents two patients with combined renal and extra-renal fibromuscular dysplasia. The aetiology, histology, and management of this interesting condition are discussed.
Case Reports Case 1
A 31-year-old mother of one child, and a smoker of 15 Please address all correspondence to: R. L. Insall, Ward 1 Office, Royal Victoria Infirmary, Newcastleupon Tyne, NE1 4LP, U.K. 0950-821X/92/060668+05$08.00/0© 1992Grune & Stratton Ltd.
cigarettes daily, presented to her general practitioner with palpitations and headache. There was no past medical history of note. Sitting blood pressure was found to be 240/140 and anti-hypertensive therapy was commenced. Failure to achieve blood pressure control despite bendrofluazide, frusemide, atenolol, nifedipine, and enalapril in various combinations resulted in referral to hospital 6 months later when an epigastric bruit was noted. One month later, renal angiography showed stenoses in the right renal and both of two left renal arteries (Fig. 1) plus a near-total stenosis of the hepatic artery. The radiographic findings were typical of fibromuscular dysplasia. At separate sittings, the left and right renal artery stenoses were dilated by transluminal balloon angioplasty. Despite successful renal artery dilatation on review angiography, the patient remains with hyper~ tension that is difficult to control, now taking methyldopa, nifedipine, and doxazosin. At no time has the patient had any abnormality of liver function and the hepatic artery stenosis remains untreated.
Case 2
A 46-year-old normotensive mother of three children, who is a non-smoker, presented to hospital with a 2week history of epigastric pain radiating to the back, with tenderness and guarding in the epigastrium. Blood tests, including liver function, abdominal radiography, and endoscopy were normal but abdominal ultrasound showed aneurysms of the coeliac and right renal arteries. The patient was known to
Fibromuscular Dysplasia
669
Fig. 2. Selectiveright renal angiogram showing a "string of beads" appearance (arrowed) typical of fibromuscular dysplasia in the proximal segment and an aneurysm of the distal segment of the renal artery.
Fig. 1. Renal angiogram showing: (1.1) "String of beads" appearance (arrowed) typical of fibromuscular dysplasia of the right and two left renal arteries; the splenic artery (c) is seen, but the hepatic artery is not visualised; (1.2) a later exposure of the same area as in (1.1) showing opacificationof an attenuated hepatic artery (b) with a stenosis at its origin. have a solitary functioning right kidney following previous left pyelonephritis and had u n d e r g o n e cholecystectomy for gall stones 14 years earlier. Angiography confirmed both the right renal aneury s m (Fig. 2) and the coeliac a n e u r y s m (Fig. 3) and s h o w e d features of fibromuscular dysplasia in the renal, coeliac, and superior mesenteric arteries. The left gastric artery was occluded near its origin and the hepatic and gastroduodenal arteries were attenuated (Fig. 3). In the absence of other findings, it was decided that the coeliac artery disease m u s t be the cause of her s y m p t o m s and, accordingly, surgical exploration with a view to bypass and ligation or excision of the coeliac a n e u r y s m was planned. Via a left thoracoabdominal incision and retro-peritoneal approach, the coeliac a n e u r y s m was controlled and opened. No
back-bleeding occurred from either left gastric, splenic, or hepatic arteries and no hepatic or splenic ischaemia appeared on cross-clamping the relevant vessels. Bypass was therefore d e e m e d unnecessary and the coeliac a n e u r y s m was simply treated by bipolar ligation with a biopsy of its wall. Histology (Figs 4 and 5) s h o w e d typical features of fibromuscular dysplasia affecting the media (medial fibroplasia) and a medial dissection of the coeliac artery with evidence of recanalisation. Blood count and chemistry remained normal in the post-operative period except for a small transient rise in alkaline phosphatase (bone and liver isoenzymes) suggesting that hepatic and splenic function were undisturbed. The patient has had no recurrence of s y m p t o m s during 18 m o n t h s follow up. The small (1.5 cm) renal aneurysm, in view of the normotension a n d solitary functioning right kidney, has remained untreated.
Discussion These two patients show m a n y features which are typical of extra-renal fibromuscular dysplasia. 12 Both are fertile y o u n g w o m e n with renal artery involvement, one with asymptomatic extra-renal disease but hypertensive, and the other symptomatic with epigastric pain and tenderness, perhaps due to acute enlargement of the coeliac aneurysm. The characterEur J Vasc Surg Vol 6, November 1992
670
R.L. Insall et aL
Fig. 3. Selective coeliac angiogram showing: left gastric artery occluded near its origin (a); attenuated hepatic artery (b); normal splenic artery (c); aneurysm of the coeliac artery with a membrane-like stenosis distally (d); small abnormal left kidney as a result of previous pyelonephritis (e).
Fig. 4. Photomicrograph of a cross-section through a non-aneurysmal segment of the coeliac artery showing a medial dissection with recanalisation: a small eccentric plaque of atheroma (a) and grossly thickened arteria media (m) are indicated.
istic r a d i o g r a p h i c a p p e a r a n c e of a " s t r i n g of b e a d s ''2 or " c o r k s c r e w ''7 is well d e m o n s t r a t e d (Figs 1 a n d 2). Renal a r t e r y disease a c c o u n t s for a p p r o x i m a t e l y 90% of cases of f i b r o m u s c u l a r d y s p l a s i a a n d carotid disease for m o s t of the r e m a i n d e r . 13 H o w e v e r , since m u l t i p l e arteries are i n v o l v e d in a r o u n d 5% of cases, Eur J Vasc Surg Vol 6, November 1992
the f i n d i n g of f i b r o m u s c u l a r d y s p l a s i a s h o u l d p r o m p t a s o n o g r a p h i c a n d / o r a n g i o g r a p h i c s u r v e y of splanchnic a n d p r o x i m a l limb vessels that are k n o w n to s o m e t i m e s be affected. This is particularly so b e c a u s e of the serious n a t u r e of the potential c o m p l i c a t i o n s of arterial o c c l u s i o n or a n e u r y s m r u p t u r e . Splenic
Fibromuscular Dysplasia
Fig. 5. Inset from Figure 4 magnified (x4) to show detail of arteria media (m) with muscle hypertrophy and disorganisation of elastic tissue. (Elastic van Gieson stain.)
aneurysms, which are the most frequent site, have a rate of rupture of 5-10°/o 11 while around 40% of hepatic aneurysms present with rupture. 4' ~0 Detection of extra-renal fibromuscular hyperplasia is therefore important, though little is known of the natural history of asymptomatic disease. Due to the 'risk of rupture, aneurysmal disease should be treated surgically when the patient is sufficiently fit. Patients who present with aneurysm rupture are also candidates for immediate surgery. For patients who present with symptomatic stenotic disease, the management to date has also been surgical, bypassing affected arterial segments 2,3,7,8,10 However, in the management of renal artery stenosis due to fibromuscular dysplasia, percutaneous transluminal angioplasty is successful in around 90% of cases. 14 As yet, there is little experience with angioplasty in extrarenal fibromuscular dysplasia 15 but it would seem reasonable to try this approach given the accepted advantages of angioplasty over surgery in other areas. The histological appearance of fibromuscular dysplasia is characteristic 16"17 and allows sub-division
671
on the basis of the distribution of the dysplastic changes within the arterial wall. 13 The most frequent pattern, "medial fibroplasia", accounts for 85% of the total, with fewer cases of perimedial dysplasia, intireal fibroplasia, and medial hyperplasia in descending order of frequency. It is thought that these subtypes represent a spectrum of the disorder rather than separate conditions. 12 The artery wall is alternately thickened by areas of hyperplasia of the media, giving rise to stenoses, and attenuated or aneurysmal in areas of disruption of the internal elastic lamina.16,17 This alternation of narrowed and dilated segments produces the characteristic macroscopic and radiographic appearance of fibromuscular dysplasia. The aetiology remains obscure but a predilection for multiparous females, right renal arteries (particularly with renal ptosis), and arteries with few branches (i.e. presumed poor supply of the arterial wall by vasa vasorum, which arise at only branchpoints) suggests hormonal, tractional stress, and nutritional influences. A congenital defect in the artery wall predisposing to the above influences has been suggested 13 but it remains difficult to explain the selective anatomical distribution of fibromuscular dysplasia. In summary, fibromuscular dysplasia is a rare condition primarily affecting renal arteries and causing resistant hypertension in young patients. In around 5% of cases, extra-renal involvement is found and in the majority of cases is an incidental finding. Symptomatic disease of visceral arteries may require urgent treatment because of the risk of rupture of the attenuated artery wall. Fibromuscular dysplasia should be remembered in the differential diagnosis of obscure abdominal pain and hypovolaemic collapse.
Acknowledgements We are grateful to Dr M. Bennett and Mr R. Hewitt for providing the histological material and to Mrs S. Convery for typing the manuscript.
References 1 LEADBETTERWF, BUIIKLANDCE. Hypertension in unilateral renal disease. J Urol 1938; 39: 611-626. 2 PALUBINSKAS AJ, RIPLEY HR. Fibromuscular hyperplasia in estrarenal arteries. Radiology 1964; 82: 451-455. 3 RIPLEYHR, LEVIN SM. Abdominal angina associated with fibromuscular hyperplasia of the celiac and superior mesenteric arteries. Angiology 1966; 17: 297-310. 4 BUSUTTILRW, BRIN BJ. The diagnosis and management of visceral artery aneurysms. Surgery 1980; 88: 619-624. Eur J Vasc Surg Vol 6, November 1992
672
R.L. Insall et aL
5 HILL LD, ANTONIUS JI. Arterial dysplasia. Arch Surg 1965; 90: 585-595. 6 WYLIEEJ, BINKLEYFM, PALUBINSKASAJ. Extrarenal fibromuscular hyperplasia, Am J Surg 1966; 112: 149-155. 7 CEAIRBONETS. Fibromuscular hyperplasia. Report of a case with involvement of multiple arteries. Am J Med 1970; 49: 103-105. 8 FOISSYP, FABREM, LEBALEURA, BUFFETC, FRILEUXC, ETIENNE JP. Aneurysm of the trunk of the superior mesenteric artery and multiple aneurysm disease of the marginal artery of the right colic artery due to fibromuscular hyperptasia. Ann Med Interne 1984; 135: 530-532. 9 PATCHEFSKYAS, PAPLANUSSH. Fibromuscular hyperplasia and dissecting aneurysm of the hepatic artery. Arch Pathol 1967; 83: 141-144. 10 PINKERTONJA, WOOD WG, FOWLER D. Fibrodysptasia with dissecting aneurysm of the hepatic artery. Surgery 1976; 79: 721723. 11 STANLEYJC, THOMPSON NW, FRY WJ. Splanchnic artery aneurysms. Arch Surg 1970; 101: 689-697.
Eur J Vasc Surg Vol 6, November 1992
12 STANLEYJC, WAKEFIELDTW. Arterial fibrodysplasia. In: RUTHERFORD RB, ed. Vascular Surgery. Vol. 16. Philadelphia: W. B. Saunders, 1989; 245-264. 13 STANLEYJC, GEWERTZBC, BOVEEL. Arterial fibrodysplasia. Histopathologic character and current etiologic concepts. Arch Surg 1975; 110: 561-566. 14 WILKINSON R. Renovascular hypertension. Curr Prac Surg 1990; 2: 38-46. 15 PARNELL AP, LOOSE HW, CHAMBERLAINJ. Fibromuscular dysplasia of the external iliac artery: treatment by percutaneous transluminal angioplasty. Br J Radiol 1988; 61: 1080-1082. 16 HEPTINSTALLRH. Dysplasia of the renal artery. In: HEPTINSTALL RH, ed. Pathology of the Kidney. Boston: Little, Brown, 1983, 252254. 17 TITUSJL, KIM H-S. Fibromuscular dysplasia. In: KISSANEJM, ed. Anderson's Pathology. St Louis: C. V. Mosby, 1990; 785-787.
Accepted 7 February 1991
CASE REPORT
Fibromuscular Dysplasia of Visceral Arteries R. L. Insall 1, J. Chamberlain 1 and H. W. C. Loose 2 Departments of 1Surgery and 2Radiology, Freeman Hospital, High Heaton, Newcastle upon Tyne, NE7 7DN, U.K. The case histories of two patients with combined renal and extra-renal fibromuscular dysplasia are presented. Readers are reminded of this rare but important condition as a cause of obscure abdominal symptoms and abdominal bleeding in the absence of atherosclerotic aortic aneurysm. The aetiology, histology, and management of the condition are discussed. Key Words: Fibromuscular dysplasia; Extra-renal; Visceral arteries.
Introduction
Fibromuscular dysplasia is a rare, non-atherosclerotic condition affecting large and medium-sized arteries. Initially recognised in patients with reno-vascular hypertension, 1 the condition has subsequently been found to affect splanchnic and iliac arteries, 2-4 aorta, intra- and extra-cranial, and axillo-brachial arteries.S" 6 Patients may present with occlusive disease 7 or with aneurysmal disease prone to dissection or rupture. 6'8-1~ In common with other aneurysmal disease, rupture carries a high mortality rate (approximately 80%) and occurs in 5-10% of cases. 11 Extra-renal fibromuscular dysplasia is rarely found without renal artery involvement and is most often seen as an incidental finding during angiographic investigation of reno-vascular hypertension, it is present in around 5% of patients with renal fibromuscular dysplasia. 12 At variance with atherosclerosis, the condition predominantly affects fertile w o m e n in the middle third of life. 13 This paper presents two patients with combined renal and extra-renal fibromuscular dysplasia. The aetiology, histology, and management of this interesting condition are discussed.
Case Reports Case 1
A 31-year-old mother of one child, and a smoker of 15 Please address all correspondence to: R. L. Insall, Ward 1 Office, Royal Victoria Infirmary, Newcastleupon Tyne, NE1 4LP, U.K. 0950-821X/92/060668+05$08.00/0© 1992Grune & Stratton Ltd.
cigarettes daily, presented to her general practitioner with palpitations and headache. There was no past medical history of note. Sitting blood pressure was found to be 240/140 and anti-hypertensive therapy was commenced. Failure to achieve blood pressure control despite bendrofluazide, frusemide, atenolol, nifedipine, and enalapril in various combinations resulted in referral to hospital 6 months later when an epigastric bruit was noted. One month later, renal angiography showed stenoses in the right renal and both of two left renal arteries (Fig. 1) plus a near-total stenosis of the hepatic artery. The radiographic findings were typical of fibromuscular dysplasia. At separate sittings, the left and right renal artery stenoses were dilated by transluminal balloon angioplasty. Despite successful renal artery dilatation on review angiography, the patient remains with hyper~ tension that is difficult to control, now taking methyldopa, nifedipine, and doxazosin. At no time has the patient had any abnormality of liver function and the hepatic artery stenosis remains untreated.
Case 2
A 46-year-old normotensive mother of three children, who is a non-smoker, presented to hospital with a 2week history of epigastric pain radiating to the back, with tenderness and guarding in the epigastrium. Blood tests, including liver function, abdominal radiography, and endoscopy were normal but abdominal ultrasound showed aneurysms of the coeliac and right renal arteries. The patient was known to
Fibromuscular Dysplasia
669
Fig. 2. Selectiveright renal angiogram showing a "string of beads" appearance (arrowed) typical of fibromuscular dysplasia in the proximal segment and an aneurysm of the distal segment of the renal artery.
Fig. 1. Renal angiogram showing: (1.1) "String of beads" appearance (arrowed) typical of fibromuscular dysplasia of the right and two left renal arteries; the splenic artery (c) is seen, but the hepatic artery is not visualised; (1.2) a later exposure of the same area as in (1.1) showing opacificationof an attenuated hepatic artery (b) with a stenosis at its origin. have a solitary functioning right kidney following previous left pyelonephritis and had u n d e r g o n e cholecystectomy for gall stones 14 years earlier. Angiography confirmed both the right renal aneury s m (Fig. 2) and the coeliac a n e u r y s m (Fig. 3) and s h o w e d features of fibromuscular dysplasia in the renal, coeliac, and superior mesenteric arteries. The left gastric artery was occluded near its origin and the hepatic and gastroduodenal arteries were attenuated (Fig. 3). In the absence of other findings, it was decided that the coeliac artery disease m u s t be the cause of her s y m p t o m s and, accordingly, surgical exploration with a view to bypass and ligation or excision of the coeliac a n e u r y s m was planned. Via a left thoracoabdominal incision and retro-peritoneal approach, the coeliac a n e u r y s m was controlled and opened. No
back-bleeding occurred from either left gastric, splenic, or hepatic arteries and no hepatic or splenic ischaemia appeared on cross-clamping the relevant vessels. Bypass was therefore d e e m e d unnecessary and the coeliac a n e u r y s m was simply treated by bipolar ligation with a biopsy of its wall. Histology (Figs 4 and 5) s h o w e d typical features of fibromuscular dysplasia affecting the media (medial fibroplasia) and a medial dissection of the coeliac artery with evidence of recanalisation. Blood count and chemistry remained normal in the post-operative period except for a small transient rise in alkaline phosphatase (bone and liver isoenzymes) suggesting that hepatic and splenic function were undisturbed. The patient has had no recurrence of s y m p t o m s during 18 m o n t h s follow up. The small (1.5 cm) renal aneurysm, in view of the normotension a n d solitary functioning right kidney, has remained untreated.
Discussion These two patients show m a n y features which are typical of extra-renal fibromuscular dysplasia. 12 Both are fertile y o u n g w o m e n with renal artery involvement, one with asymptomatic extra-renal disease but hypertensive, and the other symptomatic with epigastric pain and tenderness, perhaps due to acute enlargement of the coeliac aneurysm. The characterEur J Vasc Surg Vol 6, November 1992
670
R.L. Insall et aL
Fig. 3. Selective coeliac angiogram showing: left gastric artery occluded near its origin (a); attenuated hepatic artery (b); normal splenic artery (c); aneurysm of the coeliac artery with a membrane-like stenosis distally (d); small abnormal left kidney as a result of previous pyelonephritis (e).
Fig. 4. Photomicrograph of a cross-section through a non-aneurysmal segment of the coeliac artery showing a medial dissection with recanalisation: a small eccentric plaque of atheroma (a) and grossly thickened arteria media (m) are indicated.
istic r a d i o g r a p h i c a p p e a r a n c e of a " s t r i n g of b e a d s ''2 or " c o r k s c r e w ''7 is well d e m o n s t r a t e d (Figs 1 a n d 2). Renal a r t e r y disease a c c o u n t s for a p p r o x i m a t e l y 90% of cases of f i b r o m u s c u l a r d y s p l a s i a a n d carotid disease for m o s t of the r e m a i n d e r . 13 H o w e v e r , since m u l t i p l e arteries are i n v o l v e d in a r o u n d 5% of cases, Eur J Vasc Surg Vol 6, November 1992
the f i n d i n g of f i b r o m u s c u l a r d y s p l a s i a s h o u l d p r o m p t a s o n o g r a p h i c a n d / o r a n g i o g r a p h i c s u r v e y of splanchnic a n d p r o x i m a l limb vessels that are k n o w n to s o m e t i m e s be affected. This is particularly so b e c a u s e of the serious n a t u r e of the potential c o m p l i c a t i o n s of arterial o c c l u s i o n or a n e u r y s m r u p t u r e . Splenic
Fibromuscular Dysplasia
Fig. 5. Inset from Figure 4 magnified (x4) to show detail of arteria media (m) with muscle hypertrophy and disorganisation of elastic tissue. (Elastic van Gieson stain.)
aneurysms, which are the most frequent site, have a rate of rupture of 5-10°/o 11 while around 40% of hepatic aneurysms present with rupture. 4' ~0 Detection of extra-renal fibromuscular hyperplasia is therefore important, though little is known of the natural history of asymptomatic disease. Due to the 'risk of rupture, aneurysmal disease should be treated surgically when the patient is sufficiently fit. Patients who present with aneurysm rupture are also candidates for immediate surgery. For patients who present with symptomatic stenotic disease, the management to date has also been surgical, bypassing affected arterial segments 2,3,7,8,10 However, in the management of renal artery stenosis due to fibromuscular dysplasia, percutaneous transluminal angioplasty is successful in around 90% of cases. 14 As yet, there is little experience with angioplasty in extrarenal fibromuscular dysplasia 15 but it would seem reasonable to try this approach given the accepted advantages of angioplasty over surgery in other areas. The histological appearance of fibromuscular dysplasia is characteristic 16"17 and allows sub-division
671
on the basis of the distribution of the dysplastic changes within the arterial wall. 13 The most frequent pattern, "medial fibroplasia", accounts for 85% of the total, with fewer cases of perimedial dysplasia, intireal fibroplasia, and medial hyperplasia in descending order of frequency. It is thought that these subtypes represent a spectrum of the disorder rather than separate conditions. 12 The artery wall is alternately thickened by areas of hyperplasia of the media, giving rise to stenoses, and attenuated or aneurysmal in areas of disruption of the internal elastic lamina.16,17 This alternation of narrowed and dilated segments produces the characteristic macroscopic and radiographic appearance of fibromuscular dysplasia. The aetiology remains obscure but a predilection for multiparous females, right renal arteries (particularly with renal ptosis), and arteries with few branches (i.e. presumed poor supply of the arterial wall by vasa vasorum, which arise at only branchpoints) suggests hormonal, tractional stress, and nutritional influences. A congenital defect in the artery wall predisposing to the above influences has been suggested 13 but it remains difficult to explain the selective anatomical distribution of fibromuscular dysplasia. In summary, fibromuscular dysplasia is a rare condition primarily affecting renal arteries and causing resistant hypertension in young patients. In around 5% of cases, extra-renal involvement is found and in the majority of cases is an incidental finding. Symptomatic disease of visceral arteries may require urgent treatment because of the risk of rupture of the attenuated artery wall. Fibromuscular dysplasia should be remembered in the differential diagnosis of obscure abdominal pain and hypovolaemic collapse.
Acknowledgements We are grateful to Dr M. Bennett and Mr R. Hewitt for providing the histological material and to Mrs S. Convery for typing the manuscript.
References 1 LEADBETTERWF, BUIIKLANDCE. Hypertension in unilateral renal disease. J Urol 1938; 39: 611-626. 2 PALUBINSKAS AJ, RIPLEY HR. Fibromuscular hyperplasia in estrarenal arteries. Radiology 1964; 82: 451-455. 3 RIPLEYHR, LEVIN SM. Abdominal angina associated with fibromuscular hyperplasia of the celiac and superior mesenteric arteries. Angiology 1966; 17: 297-310. 4 BUSUTTILRW, BRIN BJ. The diagnosis and management of visceral artery aneurysms. Surgery 1980; 88: 619-624. Eur J Vasc Surg Vol 6, November 1992
672
R.L. Insall et aL
5 HILL LD, ANTONIUS JI. Arterial dysplasia. Arch Surg 1965; 90: 585-595. 6 WYLIEEJ, BINKLEYFM, PALUBINSKASAJ. Extrarenal fibromuscular hyperplasia, Am J Surg 1966; 112: 149-155. 7 CEAIRBONETS. Fibromuscular hyperplasia. Report of a case with involvement of multiple arteries. Am J Med 1970; 49: 103-105. 8 FOISSYP, FABREM, LEBALEURA, BUFFETC, FRILEUXC, ETIENNE JP. Aneurysm of the trunk of the superior mesenteric artery and multiple aneurysm disease of the marginal artery of the right colic artery due to fibromuscular hyperptasia. Ann Med Interne 1984; 135: 530-532. 9 PATCHEFSKYAS, PAPLANUSSH. Fibromuscular hyperplasia and dissecting aneurysm of the hepatic artery. Arch Pathol 1967; 83: 141-144. 10 PINKERTONJA, WOOD WG, FOWLER D. Fibrodysptasia with dissecting aneurysm of the hepatic artery. Surgery 1976; 79: 721723. 11 STANLEYJC, THOMPSON NW, FRY WJ. Splanchnic artery aneurysms. Arch Surg 1970; 101: 689-697.
Eur J Vasc Surg Vol 6, November 1992
12 STANLEYJC, WAKEFIELDTW. Arterial fibrodysplasia. In: RUTHERFORD RB, ed. Vascular Surgery. Vol. 16. Philadelphia: W. B. Saunders, 1989; 245-264. 13 STANLEYJC, GEWERTZBC, BOVEEL. Arterial fibrodysplasia. Histopathologic character and current etiologic concepts. Arch Surg 1975; 110: 561-566. 14 WILKINSON R. Renovascular hypertension. Curr Prac Surg 1990; 2: 38-46. 15 PARNELL AP, LOOSE HW, CHAMBERLAINJ. Fibromuscular dysplasia of the external iliac artery: treatment by percutaneous transluminal angioplasty. Br J Radiol 1988; 61: 1080-1082. 16 HEPTINSTALLRH. Dysplasia of the renal artery. In: HEPTINSTALL RH, ed. Pathology of the Kidney. Boston: Little, Brown, 1983, 252254. 17 TITUSJL, KIM H-S. Fibromuscular dysplasia. In: KISSANEJM, ed. Anderson's Pathology. St Louis: C. V. Mosby, 1990; 785-787.
Accepted 7 February 1991
