Vol. 118, November Printed in U.S.A.
THE JOURNAL OF UROLOGY
Copyright © 1977 by The Williams & Wilkins Co.
PRIMARY RENAL ARTERY DISSECTING ANEURYSM: A REVIEW CHADALAWADA N. RAO*
AND
JERRY G. BLAIVAS
From the Department of Urology, Tufts-New England Medical Center, Boston, Massachusetts
ABSTRACT
Primary dissecting aneurysms of the renal artery are exceedingly rare. Our recent encounter with a patient with this condition prompted a review of the literature. The diagnostic and therapeutic problems in 30 patients were analyzed and guide lines for proper management were discussed. The triad of flank pain, hematuria and hypertension of acute onset in the absence of urinary obstruction should suggest this rare condition. Dissecting aortic aneurysms extending into major arterial branches occur frequently but primary dissecting aneurysms of peripheral arteries without aortic involvement are exceedingly rare. Among 48 cases of primary dissecting aneurysms of peripheral arteries reviewed by Foord and Lewis the renal artery was the most common vessel involved (25 per cent). 1 Herein we review this rare condition and present an additional case report. MATERIAL AND METHODS
Reports of primary dissecting renal artery aneurysms through 1976 were analyzed. 1-rn Cases were included only if there was unequivocal arteriographic or pathologic evidence of a dissecting aneurysm originating in the renal artery without involvement of the aorta. There were 29 cases that met these criteria, to which we add our case for a total of 30. In 27 patients a tissue diagnosis was made, while in 3 the diagnosis was confirmed only by angiography.
the renal artery was unusually adherent to the surrounding soft tissues but no masses were apparent. On gross inspection the kidney was 13 cm. long and 2 prominent wedge-shaped infarcts were noted at the lower pole. An area of fresh hemorrhage in the wall of the artery was noted 5 mm. distal to the resected end of the main renal artery, extending through the major branch to the lower pole of the kidney and terminating in an interlobular artery. A 3 mm. fold of intima 1 cm. from the resected end of the main renal artery protruded into the lumen of the vessel and formed a funnel-like structure that narrowed the vessel lumen by about 60 per cent. Histological examination showed recent and remote hemorrhage between the outer third of the media and the external elastic membrane, and minimal evidence of intimal hyperplasia (fig. 2). In several areas duplication of the internal elastic membrane was suggested. Multiple sections failed to demonstrate neoplastic cells. The patient was followed subsequently for a year without further episodes of hematuria, flank pain or hypertension.
CASE REPORT
A 38-year-old physician, NEMCH 91-71-66, was admitted to the hospital for evaluation of bilateral flank pain and hematuria. Eighteen months earlier painless, gross, terminal hematuria developed. Blood pressure at that time was 120/80 mm. Hg and physical examination was unremarkable. Urinalysis was normal except for microhematuria. Cystoscopy and excretory urography (IVP) were normal. The symptoms remitted and the hematuria disappeared. The patient remained asymptomatic until 2 weeks before hospitalization, when he was awakened from sleep by severe, colicky left flank pain radiating to the left testicle. An IVP demonstrated a decreased concentration of contrast material in the left kidney but no evidence of a stone or obstruction. When the patient was admitted to a local hospital he had fever and chills. Intravenous ampicillin was administered although initial urine and blood cultures were sterile. During that hospitalization sustained hypertension (160/110) developed and the patient was transferred to our hospital. Physical examination was unremarkable except for hypertension (160/100) and a left varicocele. All pulses were normal and no bruits were heard. An IVP was normal (fig. 1, A). Retrograde femoral aortography and selective left renal arteriography demonstrated neovascularity at the lower pole of the left kidney (fig. 1, B). Metastatic diagnostic study was negative and radical left nephrectomy was done. At operation Accepted for publication February 18, 1977. Read at annual meeting of New England Section, American Urological Association, Majorca, Spain, October 17-25, 1976. *Requests for reprints: New England Medical Center, 171 Harrison Ave., Boston, Massachusetts 02111. 716
RESULTS
Age and sex. Patients with primary dissecting aneurysms of the renal artery ranged in age from 24 to 80 years, with an average of 55 years (fig. 3). There were 23 men and 7 women, a ratio of about 3 to 1. The right renal artery was involved in 18 instances and the left in 6. In 6 patients bilateral simultaneous dissections occurred. Signs and symptoms. Of 20 patients whose history was available for review 14 (70 per cent) presented with flank pain. Twenty-five of 28 patients (89 per cent) were hypertensive, with diastolic pressure ranging from 100 to 160 mm. Hg. In 2 patients the blood pressure was not reported. Hematuria was noted in 9 of 19 patients (50 per cent). The results of urinalysis were not reported in 11 patients. Eight of the 30 patients (37 per cent) had elevated blood urea nitrogen. Renal vein renin determinations were reported in 4 patients and were elevated in 3. Diagnosis and treatment. Data from IVPs were available for 14 patients. In 10 (71 per cent) a decrease in the size of the affected kidney was demonstrated, in 2 (14 per cent) there was non-visualization of the affected kidney and in 2 (14 per cent) the study was normal. The renal artery dissecting aneurysm was an incidental finding at autopsy in 8 of the 30 cases, and 9 of the remaining 22 died of complications from hypertension or uremia. In 9 of the remaining 13 patients (70 per cent) the diagnosis was apparent at angiography. In 3 cases retrospective analysis demonstrated the lesion, although the diagnosis had been missed on initial interpretation of the films. In 1 patient the angiogram was suggestive of polyarteritis nodosa. In our patient the presence of neovascularity suggested neoplasia.
PRIMARY RENAL ARTERY DISSECTING ANEURYSM
717
Fm. 1. A, normal IVP. B, selective left renal arteriogram with epinephrine demonstrates neovascularity and puddling of dye
Fm. 2. Photomicrograph demonstrates hemorrhage between outer third of media and internal elastic membrane (large arrow) and evidence of intimal hyperplasia (small arrow).
Thus, in 13 of 22 patients (59 per cent) the correct diagnosis was not made. Of the 13 patients treated 9 underwent nephrectomy, 3 were treated with antihypertensive medications and 1 underwent resection of the diseased artery and replacement with a woven dacron graft. All but 1 patient were normotensive after treatment but followup was limited to about a year. Pathology. The dissecting hematoma originated in the proximal renal artery in 12 of 29 patients (41 per cent), in the distal renal artery in 6 (21 per cent) and in the branch vessels in 11 (38 per cent). In 20 of 21 patients in whom data were available the dissection occurred between the media and external elastic lamina. In the remaining patient the dissec-
tion occurred between the intima and internal elastic lamina. Renal infarction was present in 18 of 22 patients who could be evaluated. DISCUSSION
By definition a renal artery dissecting aneurysm is an intramural hemorrhage that splits the wall of the involved vessel somewhere between the intimal and external elastic membrane. Although the renal artery is involved occasionally in dissecting aneurysms only 29 prior cases have been published in which the dissecting aneurysm originated in the renal artery without aortic involvement.
718
RAO AND BLAIVAS
AGE 8 SEX DISTRIBUTION
8 7 6 #pts 5 4 3
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····· ::~::
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~ Male ~
Female
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···=··· .... :.
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:·.· . ·· ! ·• •.
:.~: ::
:,:·:·. ! ;~ .. :::-: .... . ,:,
2
.... ::~-:;:
I
10
20
30
40
50
60
70
80
90
AGE Fm.3
The etiology of this rare condition is unknown. Theoretically, the dissecting hemorrhage must originate either from the intimal surface after disruption or from rupture of the vasa vasorum. In 8 of the 22 patients in whom the intima was examined (36 per cent) there was either an internal tear or disruption of the internal elastic membrane but one can only speculate whether this was the primary event or secondary to the intramural hemorrhage. Kaufman and associates suggested that many cases of renal artery stenosis are secondary to dissections through a deficient or disrupted internal elastic lamina. 14 Myxoid degeneration of the media secondary to this dissection may then give the impression that medial fibroplasia is the underlying pathology, with the dissecting aneurysm a complication. Harrison and associates have suggested that medial thickening and disruption, and degeneration of the internal elastic membrane are part of the same pathological process. They noted that 6 of 66 patients with fibromuscular dysplasia (10 per cent) had renal artery dissecting aneurysms. 17 In our review only 3 of 27 patients (9 per cent) had changes suggestive offibromuscular dysplasia. Moreover, the male to female ratio of 3 to 1 in patients with dissecting renal artery aneurysms usually is reversed in fibromuscular dysplasia. It does not appear, then, that fibromuscular dysplasia is the underlying etiology in most instances of dissecting aneurysm of the renal artery. Several investigators have implicated rupture of the vasa vasorum as the precipitating event. 10, 17• 18 In 1 series 19 of 31 patients with multiple mural aneurysms had dilatation and focal communication of the vasa vasorum with the outer third of media. 19 Nalbandian and Chason demonstrated apparent communication of the vasa vasorum with the dissecting hematoma in a patient with dissection of the coronary artery18 and Khanna and associates made a similar observation in a patient with a dissecting aneurysm of an accessory renal artery. 15 The clinical triad of the abrupt onset of hypertension, flank pain and hematuria should always suggest the possibility of acute renovascular insufficiency. Urgent IVP is mandatory and will serve to exclude an obstructive uropathy. Pyelographic findings suggestive of a renovascular accident include non-visualization of the affected kidney, decrease in renal size, delayed caliceal appearance time of the contrast medium, infundibular narrowing and delayed hyperconcentration of contrast medium within the collecting system. However, as demonstrated by 2 cases in this review the IVP may appear normal. When pyelographic findings are suggestive or if there is a clinical index of suspicion of renovascular insufficiency aortog-
raphy with selective renal arteriography should be done. Angiographic findings characteristic of dissecting aneurysms of the renal artery include irregularity in the caliber of the renal artery, local narrowing and cuffing at branch orifices and reversibility of some of these changes in followup arteriograms. 11 Of 13 patients in whom the arteriogram was available for analysis 11 had 1 of these signs. In addition, our patient demonstrated neovascularity. The proper diagnosis was not realized in more than half of the patients in this series (59 per cent), despite a clinical setting that suggested renovascular insufficiency. Since the emergence of renal arteriography as a commonplace diagnostic tool we believe that the diagnosis of dissecting aneurysm of the renal artery will be more readily apparent in the future. In all 13 treated patients hypertension was controlled by either nephrectomy (8 of9 patients), antihypertensive therapy (3 of 3 patients) or spontaneous re-entry of the dissection into vessel lumen. Followup data in these patients were inadequate to allow a meaningful appraisal of the efficacy of treatment. Since 6 of 30 patients (20 per cent) had simultaneous bilateral involvement the fear of subsequent involvement of the contralateral kidney makes one wary of performing nephrectomy as the primary treatment. On the other hand, medical antihypertensive therapy alone may allow further extension of the hemorrhage and eventual loss of the kidney. Primary reconstructive vascular operations seem most appropriate but our review demonstrated that only 3 of the 38 lesions were amenable. At present, then, it seems most prudent to treat with antihypertensive therapy unless the lesion is amenable to reconstruction and reserve nephrectomy for uncontrollable hypertension. REFERENCES
1. Foord, A.G. and Lewis, R. D.: Primary dissecting aneurysms of
peripheral and pulmonary arteries. Arch. Path., 68: 553, 1959. 2. Leibow, I. M., Cline, T., Post, R. S. and Persky, L.: Isolated bilateral simultaneous dissection of the renal arteries. Amer. J. Med., 21: 151, 1956. 3. Gilfillan, R. S., Smart, W. R. and Bostick, W. L.: Dissecting aneurysm of the renal artery. Arch. Surg., 73: 737, 1956. 4. Watson,,A. J.: Dissecting aneurysm of arteries other than the aorta. J. Path. Bact., 72: 439, 1956. 5. Boyd, J. F. and Watson, A. J.: Dissecting aneurysms due to trauma. Scottish Med. J., 1: 326, 1956. 6. Henry, L. and Burke, W. D.: Isolated dissecting aneurysms of the renal artery. Angiology, 14: 269, 1963. 7. Tuqan, N. A.: Primary dissecting aneurysm of the renal artery. J. Path. Bact., 89: 369, 1965. 8. Neuman, H. W. and Sahin, A. F.: Unilateral dissecting aneu-
PRIMARY RENAL ARTERY DISSECTING ANEURYSM
rysm of the renal artery. Canad. J. Surg., 8: 291, 1965. 9. Rosenblum, W. I.: Isolated dissecting aneurysm of the renal J. Urol., 95: 135, 1966. 10. G. W.: Primary dissecting aneurysm of the renal artery. Report of a case and review of the literature. Amer. J. Clin. Path., 45: 472, 1966. lL Hare, W. S. and Kincaid-Smith, P.: Dissecting aneurysm of the renal Radiology, 97: 255, 1970. 12. Perry, lVL Hypertension and dissecting aneurysm of the renal Arch. Surg., 102: 216, 1971. 13. Cummings, B., Lecky, J. W. and Kaufman, J. J .. Renal artery aneurysms and hypertension. J. Urol., Hl9: 144, 1973. 14. Kaufman, J. J., Coulson, W. F., Lecky, J. W. and Popjak, G.: Primary dissecting aneurysm of renal artery: report of a case causing reversible renal hypertension. Ann. Surg., 177: 259, 1973.
15. Khanna, 0. P., Nedwich, A. and Gonick, P.: Accelerated hypertension due to intramural dissection of accessory renal artery. Urology, 1: 130, 1973. 16. Meyers, D.S., Grim, C. E. and Fordkeitzer, W.: Fibromuscular dysplasia of the renal artery with medial di.ssecti.on. Amer. Med., 56: 412, 1974. 17. Harrison, E.G., Jr., Hunt, J.C. andBernatz, P. E.: of fibromuscular dysplasia of the renal artery in n,iw·v,;;oe hypertension. Amer. J. Med., 43: 97, 1967. 18. Nalbandian, R. M. and Chason, J. L.: Intramural (intramedial) dissecting hematomas in normal or otherwise unremarkable coronary arteries. A "rare" cause of death. Amer. J Path., 43: 348, 1965. 19. Harrison, E. G., Jr. and McCormick, L. J.: Pathological classification of renal arterial disease in renovascular hypertension. Mayo. Clin. Proc., 56: 412, 1974.
THE JOURNAL OF UROLOGY
Copyright © 1977 by The Williams & Wilkins Co.
PRIMARY RENAL ARTERY DISSECTING ANEURYSM: A REVIEW CHADALAWADA N. RAO*
AND
JERRY G. BLAIVAS
From the Department of Urology, Tufts-New England Medical Center, Boston, Massachusetts
ABSTRACT
Primary dissecting aneurysms of the renal artery are exceedingly rare. Our recent encounter with a patient with this condition prompted a review of the literature. The diagnostic and therapeutic problems in 30 patients were analyzed and guide lines for proper management were discussed. The triad of flank pain, hematuria and hypertension of acute onset in the absence of urinary obstruction should suggest this rare condition. Dissecting aortic aneurysms extending into major arterial branches occur frequently but primary dissecting aneurysms of peripheral arteries without aortic involvement are exceedingly rare. Among 48 cases of primary dissecting aneurysms of peripheral arteries reviewed by Foord and Lewis the renal artery was the most common vessel involved (25 per cent). 1 Herein we review this rare condition and present an additional case report. MATERIAL AND METHODS
Reports of primary dissecting renal artery aneurysms through 1976 were analyzed. 1-rn Cases were included only if there was unequivocal arteriographic or pathologic evidence of a dissecting aneurysm originating in the renal artery without involvement of the aorta. There were 29 cases that met these criteria, to which we add our case for a total of 30. In 27 patients a tissue diagnosis was made, while in 3 the diagnosis was confirmed only by angiography.
the renal artery was unusually adherent to the surrounding soft tissues but no masses were apparent. On gross inspection the kidney was 13 cm. long and 2 prominent wedge-shaped infarcts were noted at the lower pole. An area of fresh hemorrhage in the wall of the artery was noted 5 mm. distal to the resected end of the main renal artery, extending through the major branch to the lower pole of the kidney and terminating in an interlobular artery. A 3 mm. fold of intima 1 cm. from the resected end of the main renal artery protruded into the lumen of the vessel and formed a funnel-like structure that narrowed the vessel lumen by about 60 per cent. Histological examination showed recent and remote hemorrhage between the outer third of the media and the external elastic membrane, and minimal evidence of intimal hyperplasia (fig. 2). In several areas duplication of the internal elastic membrane was suggested. Multiple sections failed to demonstrate neoplastic cells. The patient was followed subsequently for a year without further episodes of hematuria, flank pain or hypertension.
CASE REPORT
A 38-year-old physician, NEMCH 91-71-66, was admitted to the hospital for evaluation of bilateral flank pain and hematuria. Eighteen months earlier painless, gross, terminal hematuria developed. Blood pressure at that time was 120/80 mm. Hg and physical examination was unremarkable. Urinalysis was normal except for microhematuria. Cystoscopy and excretory urography (IVP) were normal. The symptoms remitted and the hematuria disappeared. The patient remained asymptomatic until 2 weeks before hospitalization, when he was awakened from sleep by severe, colicky left flank pain radiating to the left testicle. An IVP demonstrated a decreased concentration of contrast material in the left kidney but no evidence of a stone or obstruction. When the patient was admitted to a local hospital he had fever and chills. Intravenous ampicillin was administered although initial urine and blood cultures were sterile. During that hospitalization sustained hypertension (160/110) developed and the patient was transferred to our hospital. Physical examination was unremarkable except for hypertension (160/100) and a left varicocele. All pulses were normal and no bruits were heard. An IVP was normal (fig. 1, A). Retrograde femoral aortography and selective left renal arteriography demonstrated neovascularity at the lower pole of the left kidney (fig. 1, B). Metastatic diagnostic study was negative and radical left nephrectomy was done. At operation Accepted for publication February 18, 1977. Read at annual meeting of New England Section, American Urological Association, Majorca, Spain, October 17-25, 1976. *Requests for reprints: New England Medical Center, 171 Harrison Ave., Boston, Massachusetts 02111. 716
RESULTS
Age and sex. Patients with primary dissecting aneurysms of the renal artery ranged in age from 24 to 80 years, with an average of 55 years (fig. 3). There were 23 men and 7 women, a ratio of about 3 to 1. The right renal artery was involved in 18 instances and the left in 6. In 6 patients bilateral simultaneous dissections occurred. Signs and symptoms. Of 20 patients whose history was available for review 14 (70 per cent) presented with flank pain. Twenty-five of 28 patients (89 per cent) were hypertensive, with diastolic pressure ranging from 100 to 160 mm. Hg. In 2 patients the blood pressure was not reported. Hematuria was noted in 9 of 19 patients (50 per cent). The results of urinalysis were not reported in 11 patients. Eight of the 30 patients (37 per cent) had elevated blood urea nitrogen. Renal vein renin determinations were reported in 4 patients and were elevated in 3. Diagnosis and treatment. Data from IVPs were available for 14 patients. In 10 (71 per cent) a decrease in the size of the affected kidney was demonstrated, in 2 (14 per cent) there was non-visualization of the affected kidney and in 2 (14 per cent) the study was normal. The renal artery dissecting aneurysm was an incidental finding at autopsy in 8 of the 30 cases, and 9 of the remaining 22 died of complications from hypertension or uremia. In 9 of the remaining 13 patients (70 per cent) the diagnosis was apparent at angiography. In 3 cases retrospective analysis demonstrated the lesion, although the diagnosis had been missed on initial interpretation of the films. In 1 patient the angiogram was suggestive of polyarteritis nodosa. In our patient the presence of neovascularity suggested neoplasia.
PRIMARY RENAL ARTERY DISSECTING ANEURYSM
717
Fm. 1. A, normal IVP. B, selective left renal arteriogram with epinephrine demonstrates neovascularity and puddling of dye
Fm. 2. Photomicrograph demonstrates hemorrhage between outer third of media and internal elastic membrane (large arrow) and evidence of intimal hyperplasia (small arrow).
Thus, in 13 of 22 patients (59 per cent) the correct diagnosis was not made. Of the 13 patients treated 9 underwent nephrectomy, 3 were treated with antihypertensive medications and 1 underwent resection of the diseased artery and replacement with a woven dacron graft. All but 1 patient were normotensive after treatment but followup was limited to about a year. Pathology. The dissecting hematoma originated in the proximal renal artery in 12 of 29 patients (41 per cent), in the distal renal artery in 6 (21 per cent) and in the branch vessels in 11 (38 per cent). In 20 of 21 patients in whom data were available the dissection occurred between the media and external elastic lamina. In the remaining patient the dissec-
tion occurred between the intima and internal elastic lamina. Renal infarction was present in 18 of 22 patients who could be evaluated. DISCUSSION
By definition a renal artery dissecting aneurysm is an intramural hemorrhage that splits the wall of the involved vessel somewhere between the intimal and external elastic membrane. Although the renal artery is involved occasionally in dissecting aneurysms only 29 prior cases have been published in which the dissecting aneurysm originated in the renal artery without aortic involvement.
718
RAO AND BLAIVAS
AGE 8 SEX DISTRIBUTION
8 7 6 #pts 5 4 3
::,:.:.:
····· ::~::
.,.,. .........
~ Male ~
Female
"'•'
:.·: \·.:
···=··· .... :.
. t, .•
:·.· . ·· ! ·• •.
:.~: ::
:,:·:·. ! ;~ .. :::-: .... . ,:,
2
.... ::~-:;:
I
10
20
30
40
50
60
70
80
90
AGE Fm.3
The etiology of this rare condition is unknown. Theoretically, the dissecting hemorrhage must originate either from the intimal surface after disruption or from rupture of the vasa vasorum. In 8 of the 22 patients in whom the intima was examined (36 per cent) there was either an internal tear or disruption of the internal elastic membrane but one can only speculate whether this was the primary event or secondary to the intramural hemorrhage. Kaufman and associates suggested that many cases of renal artery stenosis are secondary to dissections through a deficient or disrupted internal elastic lamina. 14 Myxoid degeneration of the media secondary to this dissection may then give the impression that medial fibroplasia is the underlying pathology, with the dissecting aneurysm a complication. Harrison and associates have suggested that medial thickening and disruption, and degeneration of the internal elastic membrane are part of the same pathological process. They noted that 6 of 66 patients with fibromuscular dysplasia (10 per cent) had renal artery dissecting aneurysms. 17 In our review only 3 of 27 patients (9 per cent) had changes suggestive offibromuscular dysplasia. Moreover, the male to female ratio of 3 to 1 in patients with dissecting renal artery aneurysms usually is reversed in fibromuscular dysplasia. It does not appear, then, that fibromuscular dysplasia is the underlying etiology in most instances of dissecting aneurysm of the renal artery. Several investigators have implicated rupture of the vasa vasorum as the precipitating event. 10, 17• 18 In 1 series 19 of 31 patients with multiple mural aneurysms had dilatation and focal communication of the vasa vasorum with the outer third of media. 19 Nalbandian and Chason demonstrated apparent communication of the vasa vasorum with the dissecting hematoma in a patient with dissection of the coronary artery18 and Khanna and associates made a similar observation in a patient with a dissecting aneurysm of an accessory renal artery. 15 The clinical triad of the abrupt onset of hypertension, flank pain and hematuria should always suggest the possibility of acute renovascular insufficiency. Urgent IVP is mandatory and will serve to exclude an obstructive uropathy. Pyelographic findings suggestive of a renovascular accident include non-visualization of the affected kidney, decrease in renal size, delayed caliceal appearance time of the contrast medium, infundibular narrowing and delayed hyperconcentration of contrast medium within the collecting system. However, as demonstrated by 2 cases in this review the IVP may appear normal. When pyelographic findings are suggestive or if there is a clinical index of suspicion of renovascular insufficiency aortog-
raphy with selective renal arteriography should be done. Angiographic findings characteristic of dissecting aneurysms of the renal artery include irregularity in the caliber of the renal artery, local narrowing and cuffing at branch orifices and reversibility of some of these changes in followup arteriograms. 11 Of 13 patients in whom the arteriogram was available for analysis 11 had 1 of these signs. In addition, our patient demonstrated neovascularity. The proper diagnosis was not realized in more than half of the patients in this series (59 per cent), despite a clinical setting that suggested renovascular insufficiency. Since the emergence of renal arteriography as a commonplace diagnostic tool we believe that the diagnosis of dissecting aneurysm of the renal artery will be more readily apparent in the future. In all 13 treated patients hypertension was controlled by either nephrectomy (8 of9 patients), antihypertensive therapy (3 of 3 patients) or spontaneous re-entry of the dissection into vessel lumen. Followup data in these patients were inadequate to allow a meaningful appraisal of the efficacy of treatment. Since 6 of 30 patients (20 per cent) had simultaneous bilateral involvement the fear of subsequent involvement of the contralateral kidney makes one wary of performing nephrectomy as the primary treatment. On the other hand, medical antihypertensive therapy alone may allow further extension of the hemorrhage and eventual loss of the kidney. Primary reconstructive vascular operations seem most appropriate but our review demonstrated that only 3 of the 38 lesions were amenable. At present, then, it seems most prudent to treat with antihypertensive therapy unless the lesion is amenable to reconstruction and reserve nephrectomy for uncontrollable hypertension. REFERENCES
1. Foord, A.G. and Lewis, R. D.: Primary dissecting aneurysms of
peripheral and pulmonary arteries. Arch. Path., 68: 553, 1959. 2. Leibow, I. M., Cline, T., Post, R. S. and Persky, L.: Isolated bilateral simultaneous dissection of the renal arteries. Amer. J. Med., 21: 151, 1956. 3. Gilfillan, R. S., Smart, W. R. and Bostick, W. L.: Dissecting aneurysm of the renal artery. Arch. Surg., 73: 737, 1956. 4. Watson,,A. J.: Dissecting aneurysm of arteries other than the aorta. J. Path. Bact., 72: 439, 1956. 5. Boyd, J. F. and Watson, A. J.: Dissecting aneurysms due to trauma. Scottish Med. J., 1: 326, 1956. 6. Henry, L. and Burke, W. D.: Isolated dissecting aneurysms of the renal artery. Angiology, 14: 269, 1963. 7. Tuqan, N. A.: Primary dissecting aneurysm of the renal artery. J. Path. Bact., 89: 369, 1965. 8. Neuman, H. W. and Sahin, A. F.: Unilateral dissecting aneu-
PRIMARY RENAL ARTERY DISSECTING ANEURYSM
rysm of the renal artery. Canad. J. Surg., 8: 291, 1965. 9. Rosenblum, W. I.: Isolated dissecting aneurysm of the renal J. Urol., 95: 135, 1966. 10. G. W.: Primary dissecting aneurysm of the renal artery. Report of a case and review of the literature. Amer. J. Clin. Path., 45: 472, 1966. lL Hare, W. S. and Kincaid-Smith, P.: Dissecting aneurysm of the renal Radiology, 97: 255, 1970. 12. Perry, lVL Hypertension and dissecting aneurysm of the renal Arch. Surg., 102: 216, 1971. 13. Cummings, B., Lecky, J. W. and Kaufman, J. J .. Renal artery aneurysms and hypertension. J. Urol., Hl9: 144, 1973. 14. Kaufman, J. J., Coulson, W. F., Lecky, J. W. and Popjak, G.: Primary dissecting aneurysm of renal artery: report of a case causing reversible renal hypertension. Ann. Surg., 177: 259, 1973.
15. Khanna, 0. P., Nedwich, A. and Gonick, P.: Accelerated hypertension due to intramural dissection of accessory renal artery. Urology, 1: 130, 1973. 16. Meyers, D.S., Grim, C. E. and Fordkeitzer, W.: Fibromuscular dysplasia of the renal artery with medial di.ssecti.on. Amer. Med., 56: 412, 1974. 17. Harrison, E.G., Jr., Hunt, J.C. andBernatz, P. E.: of fibromuscular dysplasia of the renal artery in n,iw·v,;;oe hypertension. Amer. J. Med., 43: 97, 1967. 18. Nalbandian, R. M. and Chason, J. L.: Intramural (intramedial) dissecting hematomas in normal or otherwise unremarkable coronary arteries. A "rare" cause of death. Amer. J Path., 43: 348, 1965. 19. Harrison, E. G., Jr. and McCormick, L. J.: Pathological classification of renal arterial disease in renovascular hypertension. Mayo. Clin. Proc., 56: 412, 1974.
