80 Letters to the Editor

threatening renal dysfunction following subsequent occlusion of the IVC at the site of a suprarenal filter, we positioned a TGF infrare- nally via the right jugular vein just cranially to the DVT and just caudally to the inflow of the bilateral renal veins (Fig. 2). No sign of pulmonary thromboembolism or occlusion of the right IVC has occurred during follow-up treatment of her ovarian cancer.

Comments

It is well known that, in double IVC, the two cavae may be of nearly equal size, as in our patients, or one may be substantially smaller and several types of infrarenal collaterals exist in double IVCs [1]. In our patients there were no direct major infrarenal connections between the two cavae, leaving the right and left iliac veins to drain exclusively into their respective right and left IVCs.

The most common placement position for the IVC filter is in the infrarenal portion because of potential renal dysfunction following filter placement with or without occlusion. In recent years several investigators have reported on the safety and clinical utility of suprarenal placement, especially with TGF, because of the minimal risk of caval occlusion after placement [2]. On the basis of these reports, we positioned one TGF suprarenally in the patient with DVT in the left IVC and he showed no renal dysfunction during follow-up. Dual filter placement in both the right and left IVC for patients with this anomaly has been reported [3], however, to our knowledge, placement of a single suprarenal filter has only been reported in one patient [4].

For patients with DVT in the right IVC several options for filter placement could be considered, including suprarenal placement, single infrarenal placement in the right IVC, and dual infrarenal placement in both the right and left IVC, Considering the minimal risk of IVC occlusion at the site of the TGF, suprarenal or dual placement for both-sided IVC is indicated tbr complete filtration. However, we selected single infrarenal placement in the right IVC of our patient 2 because of the risk of renal dysfunction following filter occlusion, as the patient had antithrombin-Ill deficiency with a thrombogenic tendency. As a matter of fact, the DVT in her right IVC appeared while she was undergoing oral anticoagulation ther- apy. Placement of an additional filter in the left IVC should be performed when the right IVC is occluded, because recurrent pul- monary thromboembolism through the enlarged pelvic collaterals and ascending lumbar vein and/or hemiazygos vein has been re- ported [5].

In conclusion, suprarenal placement of the TGF is definitely indicated for patients with DVT in either side of a double IVC, except in patients with thrombogenic disease.

Koji Sugimoto, M.D.

Kazufumi Imanaka, M.D. Tetsuya Kawabe, M.D.

Department of Radiology Nishi-Kobe Medical Center

Kobe, Japan

Shozo Hirota, M.D.

Central Radiological Division Kohe University School of Medicine

Kobe, Japan

References 1. Trigaux JP, Vandroogenbroek S, De Wispelaere JF, Lacrosse M, Jamert

J (1998) Congenital anomalies of the inferior vena cava and left renal vein: Evaluation with spiral CT. J Vasc Interv Radiol 9:339-345

2. Greenfield LA, Proctor MC (1998) Suprarenat filter placement. J Vasc Surg 28:432-438

3. Rohler MJ, Cutler BS (I988) Placement of two Greenfield filters in a duplicated vena cava. Surgery 104:572-574

4. Reed RA, Teitelbaum GP, Taylor FC, Pentecost MJ, Roehm JOF (1991) Use of the Bird's Nest filter in oversized inferior venae cavae. J Vasc lnterv Radiol 2:447-450

5. Teitelbaum GP, McKay RH, Katz MD (1993) Bird's Nest filter place- ment within an enlarged hemiazygos vein for prevention of pulmonary embolism. Cardiovasc lntervent Radiol 16:119-121

Re: Endovascular Management of an Inferior Gluteal Artery Pseudoaneurysm Secondary to Tuberculous Cold Abscess

We report a case of an inferior gluteal artery pseudoaneurysm that developed in the bed of a tuberculous pre-sacral cold abscess. Endovascular transcatheter coil embolization of the pseudoaneu rysm was accomplished successfully thus obviating the need for difficult surgery. We did not find mention of arterial involvement leading to a pseudoaneurysm secondary to a tuberculous pre-sacral abscess in the English literature.

A 12-year-old boy presented with a 2-month history of fever and pain in the right lilac lbssa. Clinical examination revealed flexion deformity of the right hip and tenderness in the right iliac fossa. Laboratory investigations were unremarkable except for an ele- vated erythrocyte sedimentation rate (ESR) (65 mm/hr) and mild leukocytosis (WBC: 12,500/mm 3, polymorphs: 30%, lymphocytes: 62%).

Ultrasonography demonstrated a large presacral collection with a pulsatile focal lesion in its bed. Color Doppler showed arterial signals within the lesion, suggesting a pseudoaneurysm of an in- ternal iliac branch vessel. A plain radiograph of the pelvis revealed an ill-defined osteolytic lesion in the ala and body of the first sacral vertebra on the right side. Selective right internal lilac artery injec- tion demonstrated a large pseudoaneurysm arising from the inferior gluteal artery (Fig. 1). The feeding artery of the aneurysm was embolized using a single (3-cm-long and 3-mm-diameter) Hilal microcoil (Cook, Bloomington, IN, USA), after which there was complete obliteration of the pseudoaneurysm (Fig. 2). A follow-up CT scan of the pelvis showed multiple loculi of a presacral abscess with the thrombosed pseudoaneurysm in its bed. There were mul- tiple gluteal abscesses (Fig. 3). Ultrasound-guided aspiration of the abscesses was performed. The culture grew Mycobacterium tuber- culosis on Lowenstein-Jensen medium, confirming the tuberculous nature of the abscesses. The patient received four-drug antituber- culous chemotherapy (Isoniazid, Rifampicin, Pyrazinamide, and Ethambutol) for a period of 6 months. He has been asymptomatic for the last 8 months.

Isolated hypogastric artery (HA) aneurysms are distinctly rare, with a reported incidence of approximately 0.4% [ 1 ]. Atheroscer- osis is the most common etiology underlying these aneurysms. Posttraumatic, mycotic, iatrogenic, and congenital aneurysms of the HA have been infrequently reported in the literature [1-3].

Isolated HA aneurysms represent true pelvic aneurysms [2]. These aneurysms are frequently asymptomatic. They exhibit relent- less, progressively expansile growth and present late, secondary due either to rupture or compression on neighboring structures [1, 3]. Clinical manifestations reflect the compressive effect: urinary

L e t t e r s t o t h e E d i t o r 81

Fig. 1. Internal lilac artery injection reveals a large pseudoaneurysm of the inferior gluteal artery. The abscesses cause displacement of branches of the internal lilac artery.

Fig. 2. Internal iliac artery injection following coil embolization shows complete obliteration of the pseudoaneurysm.

Fig. 3. Contrast-enhanced CT scan of the pelvis demonstrates multiple tuberculous cold abscesses which show peripheral enhancement. The coil is seen within the neck of the pseudoaneurysm (arrow).

tract obstruction consequent to the mass effect on the adjacent ureter and urinary bladder is the most common mode of presenta- tion [2[. Direct ureteric compression or encasement by the perian- eurysmal fibrosis results in hydronephrosis and its attendant complications [2]. Recto-sigmoid compression leads to constipa- tion [2]. Compressive neuropathy involving sciatic, femoral, and obturator nerves secondary to HA aneurysms have been described in the literature [4, 5]. Isolated case reports of iliofemoral venous thrombosis due to HA aneurysm also exist [1].

Rupture of the aneurysm is a catastrophic complication with a

reported mortality of 50%-75% [6]. Natural history suggests a 33% rupture rate tk~r HA aneurysms [3]. The aneurysms erupt into either the retroperitoneum or adjacent structures such as the rectum, urinary bladder, or ureter [2, 7].

The deep location of HA aneurysms makes surgical exploration difficult. Injury to adjacent vital, visceral, and neurovascular struc- tures are potential complications of the surgery [1]. Extensive hemorrhage may occur during aneurysmectomy [2]. Mortality rates of 10% and 50%, respectively, for elective and emergency surgery

are remarkably high [ 1]. Our patient presented with a right-sided tuberculous presacral

abscess and a pseudoaneurysm was incidentally detected. Despite its large size, the aneurysm did not produce any compressive symptoms. Its deep anatomic location and relatively easier endo- vascular access prompted us to perform transcatheter coil emboli- zation. Following successful obliteration of this aneurysm, potential complications and the need fnr a surgical treatment were averted.

In conclusion, aneurysms developing in a bed of tuberculous

82 Letters to the Editor

abscess cavities are infrequent, and endovascular treatment pro- vides successful treatment.

Hemam Deshmukh, M.D. Srinirasa Prasad, M.D.

Tufail Pantankar, M.D.

Depar tment of Radiology King Edward Memorial Hospital

Bombay, India

References 1.. Perdue GD. Mittenthal MJ, Smith RB, Salam AA (1983) Aneurysms of

the internal iliac artery. Surgery 93:243-246

2. Krupski WC, Bass A, Rosenberg GD, DilEey RB, Stoney RJ (1989) The elusive isolated hypogastric artery aneurysm: Novet presentations. J Vase Surg t0:557-562

3. Richardson JW, Greenfield LJ (1988) Natural history and management of iliac aneury'sms, l Vase Surg 8:165-I7l

4. Soimakallio S, Oksala I (1982) Sciatic pain from an aneurysm of the internal lilac artery. Ann Chit Gynaecol 71:172-174

5. Waldman L Braun AI (1977) Femoral neuropathy secondary to iliac artery aneurysm. South Med J 70:1243-1244

6. Kasulke RJ, Clifford A, Nichols K, Silver D (1982) Isolated atheroscle- rotic aneurysms of the internal lilac arteries: Report of two cases and review of literature. Arch Surg t 17:73-77

7. Thiry AJ, Struyven J, Van DeCasseye M (1980) Spontaneous rupture of right lilac aneurysm into the ureter. Urology 16:101-103