Matrix: September 2008

Osteoid osteoma is a benign lesion that accounts for approximately 10% of benign bone tumors. It occurs predominantly in children and young adults between 10 and 25, affecting males twice as often as females. The clinical presentation typically consists of pain, which is often worst at night, increased skin temperature, sweating, and tenderness in the affected region. Pain is completely relieved by salicylates in many cases.
Predilection sites are proximal femur, and diaphysis of long bones, which account for more than half of all cases, and less often foot and the posterior elements of the spine (1). Osteoid osteomas are usually detected on radiographs, typically showing a radiolucent nidus surrounded by sclerosis in the cortex of the bone. If an osteoid osteoma is suspected and radiographs are negative, skeletal scintigraphy is especially useful with a sensitivity of 100% (2). Radionuclide angiography and tissue-phase imaging often, but not always, show prominent tracer delivery and early localization. On skeletal-phase images a well-localized, focal tracer uptake is typically noted (3). Characteristic is a cloud of diffuse increase of radiotracer around the prominent focus, which is better seen on images obtained with pinhole magnification technique (4). In complicated cases computed tomography might be helpful to visualize the nidus. Scintigraphy also is contributory for treatment of patients with osteoid osteoma by ensuring complete removal of the lesion. This can be achieved either by imaging the specimen that should demonstrate a normal margin of bone around the lesion or intraoperatively with a mobile gamma camera, demonstrating that no residual activity suggestive of osteoid osteoma tissue is left (5).

D/D: Osteomyelitis

LARGE ADRENAL PSEUDOCYST
CASE REPORT WITH REVIEW OF LITERATURE

Authors: H.S.Das, P.Hatimota, P.Hazarika, C.D.Choudhury,
*S. K. Barua, **S.J.Baruah
Institution: Matrix, G.S.Road, Guwahati-5 and Guwahati Medical College & Hospital
Key Words: Adrenal cyst MRI
Conflict of interest: None

INTRODUCTION:

Cystic pathologies of the adrenal gland are rare with an incidence of 0.06% in 1400 autopsies. The cyst most commonly found in the adrenal gland are Endothelial cyst (45%), Pseudocyst (40%), Epithelial cyst ((9%) and Parasitic cyst (7%). Pseudocysts are consequences of haemorrhage and degeneration and are usually nonfunctional.
Pseudocysts consist of a hyalinized fibrous capsule containing nest of adrenal cortical cells and amorphous cystic contents composed of admixture of serum, blood and fibrin. Adrenal pseudo cyst vary greatly in size from microscopic to more than 50 cm with highest incidence in 5th and 6th decade with female preponderance.
Symptoms are usually associated with large cyst due to compression of surrounding viceras, pain & vague GI complaints. Imaging studies by CT scan & preferably by MRI Scan helps it to differentiate it from other adrenal pathologies. Surgical extirpation is indicated in presence of symptoms, endocrine abnormalities, complication, large size or suspicion of malignancy.
We report a case of symptomatic pseudo cyst of adrenal gland in an adult female without any hormonal abnormalities which was excised through thoraco-abdominal approach. Surgery was uneventful and patient is asymptomatic at 18 months of follow up.

CASE REPORT:

A 35 years old female presented with a one year history of non specific abdominal discomfort & occasional pain in left upper abdomen. Routine laboratory tests were within normal range. USG showed a well defined approx. 10 cm cystic mass in relation to upper pole of left kidney. MRI showed a large cystic mass separated from upper pole of the kidney with a low signal intensity in T1 weighted images and high signal intensity in T2 weighted images. A complete endocrine workup failed to detect any hormonal hypersecretion. A prospective diagnosis of left adrenal cyst was made and the lesion was excised through thoraco-abdominal approach via 11th rib.
The cyst measured approx. 10 cm in its largest dimension which on cutting open revealed chocolate colored fluid. The wall thickness varied from 0.1 to 0.2 cm. and pathological section revealed fibrous wall without any epithelial lining. The patient had an uneventful post operative recovery. She is completely symptom free at 18 months of follow up visits.

DISCUSSION:

Cysts of the adrenal gland are uncommon lesions and represent 80% of cystic adrenal masses. The etiology of pseudocyst is not well understood but is believed to arise from organization of prior haemorrhage or infectious process (1). Pseudocyst account for 40% of all cystic lesion of the adrenal gland and are consequences of haemorrhage and degeneration (2).
Most adrenal cyst are asymptomatic and less then 10 cm in diameter when discovered incidentally (3) or at autopsy (4). Symptoms appear when pseudo cyst enlarges sufficiently to cause pain and GI disturbances or become palpable (3) as in our patient. Large cyst has tendency to develop complications such as intractable haemorrhage and rupture which can manifest as a surgical emergency (5).

The haemorrhage within these lesions often give atypical imaging features on CT. Ultrasonography which could be confused with an adrenal tumor (6) . MRI is useful in differential diagnosis of adrenal cyst (7) and can differentiate it from pheochromocytoma (8).
MRI shows homogenously low intensity on T1 weighted images and high intensity on T2 weighted images in case of adrenal pseudo cyst (9, 10).
Pseudocyst may be isolated or associated with primary adrenal neoplasm such as Pheochromocytoma, adrenal adenoma, adrenocortical carcinoma and neuroblastoma (11). Pseudocyst could be confused with adrenal tumors both clinically and radiographically (12) . The more complex pseudocyst should be distinguished from cystic degeneration in adrenal malignancy and from cystic renal cell carcinoma in upper pole (2) .

Surgical excision is indicated in presence of symptoms (13), endocrine abnormality (even when subclinical), complications, large size (>5 cm) or suspicion of malignancy (14). Laparoscopic drainage (15, 16) or open surgical extirpation with preservation of adrenal tissue remains the treatment of choice. Large size, increased wall thickness or calcification are features of malignant changes which should be excised and followed up for cystic recurrence, late metastasis or adrenal endocrine dysfunction.
Other lesions that should be considered in the differential diagnosis of cystic adrenal masses are endothelial cyst, lymphangioma, epithelial cyst and parasitic (hydatid) cysts (17, 18).

REFERENCES:

1. M.A.Habra , Barry W Feig , Steven G Waguespack. , Adrenal Pseudocyst
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rupture of adrenal pseudocyst leading to massive haemorrhage in

retroperitoneum , Int. Braz. J Urol. 2004; 30 (1), Abstract from SciELo Brazil

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cyst- report of two cases and review of literature. Ann. Acad. Med. Singapore

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Pseudocyst. J Urol, 1994;154(1): 150-2

7. Ito N., Fujimoto H, Arai Y, Nishimura K et. al. Two cases of adrenal cyst- the

meaning of imaging in diagnosing adrenal cyst. Hinyokika Kiyo, 1989;35(7): 1161-6

8. Hidetaka Suga et. al. , 14C, Jan 2003; 42(1) Crossed ref. Medline

9. Yashushi Tanuma , Makoto Kimura , Shigeru Sakai. Adrenal Cyst- A review of the

Japanese Literature and report of a case. International Journal of Urology, 2001;

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presenting with epigastric distress and abdominal distension ,
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management , Int. Urol. Nephrol., 1998; 30(4): 369-76

13. N. Sezhian, D. Rimal , G Suresh . Adrenal Pseudocyst- Diagnostic Dilema
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14. Manuel Suarez, Sheldon Bastacky, Vascular adrenal cyst . Final Diag. Case- 182,

2005, Crossed ref. Medline

15. Koksoy Ferda N , Yucel Osman , Celik Atilla et. al. Laparoscopic management of giant

adrenal cyst : Case report , Surg. Lap. End. PCN Technique, 2001;11(6); 379-81

16. Prashad R., Kumar M., Pseudocyst of adrenal gland,
Med. J, Malayasia, 2002; 57(1): 125-7

17. Satou T.,Uesugi T , Nakai Y et. al. , Case of adrenal lymphangioma with atypical

lymphocytes in aspirate cytology. Diag. Cytopathol., 2003; 29: 87-90

18. Ackay MN , Akcay G, Balik AA , Boyuk A , Hydatid cyst of the adrenal gland : review

of nine patients. World J Surg, 2004;28: 97-99

Figures :
1- MRI , 2- Specimen , 3- Histopathology

* Registrar Deptt of Urology, GMCH
** Prof Deptt of Urology, GMCH

Address for Correspondence:
Dr Himadri Sikhor Das,
Matrix,1st Byelane Tarun Nagar
Near Rajiv Bhawan, G.S.Road,
Guwahati-5
Tel:+0361-2595078
Email: drhsdas@gmail.com

Matrix

Thursday, September 25, 2008

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Wednesday, September 24, 2008

Fwd: Paper Request

Saturday, September 20, 2008

osteoid osteoma