Can the Requirement of a Diversion Procedure Be Predicted after an Uncomplicated Intracranial Hydatid Cyst Surgery?

Case Report Pediatr Neurosurg 2006;42:383–386 DOI: 10.1159/000095570 Received: September 6, 2005 Accepted after revision: January 14, 2006 Can the R...
Author: Malcolm Summers
1 downloads 1 Views 347KB Size
Case Report Pediatr Neurosurg 2006;42:383–386 DOI: 10.1159/000095570

Received: September 6, 2005 Accepted after revision: January 14, 2006

Can the Requirement of a Diversion Procedure Be Predicted after an Uncomplicated Intracranial Hydatid Cyst Surgery? Çag˘ atay Önal Rezzan Erguvan-Önal Cengiz Yakinci Ali Karayol Metin Atambay Nilgün Daldal ˙I nonü University School of Medicine Departments of Neurosurgery, Pathology, Pediatrics and Parasitology, Malatya, Turkey

Key Words Hydatid cyst  Echinococcus  Shunt  Brain  Pericyst

Abstract Intracranial hydatidosis is mainly a pediatric disease. Surgical evacuation of the mass in toto is the gold standard of therapy. No concise data related to the requirement of diversion procedures after uncomplicated hydatid cyst removal is encountered in the literature. The aim of this report is to focus on this idea and estimate the necessity of a diversion procedure beforehand. A 6-yearold girl both with intracranial and renal involvement of hydatidosis underwent surgery. Intact removal of the intracranial cyst harboring daughter vesicles was achieved. A persistent porencephalic cyst at the operative site required a shunt 6 months after surgery. Thick pericyst formation was blamed for this specific progress and the pathophysiology is discussed. Copyright © 2006 S. Karger AG, Basel

Introduction

Intracranial hydatid cysts consist nearly 1% of pediatric intracranial mass lesions in endemic areas [1–3]. A comprehensive knowledge of the disease with extensive

© 2006 S. Karger AG, Basel 1016–2291/06/0426–0383$23.50/0 Fax +41 61 306 12 34 E-Mail [email protected] www.karger.com

Accessible online at: www.karger.com/pne

radiological evaluation, especially with MRI, has a significant impact on the results of surgical treatment [4–6]. There are no instructive data on either the future need or the frequency of a diversion procedure after intact removal of intracranial hydatid cysts in the literature.

Case Report A 6-year-old girl was admitted to our neurosurgery unit with the initial symptoms of increased intracranial pressure. She was awake and complaining of headache. Neurological examination revealed bilateral papilledema. Cranial CT and MRI revealed a right parietooccipital mass with smooth borders involving daughter vesicles concordant with hydatid cyst (fig. 1–3A, B). The mass was evacuated in toto without rupture including the firm pericyst surrounding the mass (fig. 3C). The examination of the daughter vesicles revealed fertile scoleces while the hydatid fluid surrounding the vesicles within the solitary mass was infertile. Early follow-up was uneventful except for a radiologically verified postoperative porencephalic cyst. She was referred to the pediatric surgery unit due to renal hydatidosis where she was later operated on (fig. 4). Six months after the neurosurgical intervention, the patient was readmitted with recurrent symptoms of increased intracranial pressure. CT revealed dilated ventricles with persistent porencephalic cyst (fig. 5). A cystoperitoneal shunt was inserted which relieved the increased intracranial pressure (fig. 6). The course for 25 months after the second intervention was uneventful.

Çag˘ atay Önal, MD Department of Neurosurgery I˙ nonü University School of Medicine, PB 133 TR–44069 Malatya (Turkey) Tel. +90 532 4420 600, Fax +90 324 2371 596, E-Mail [email protected]

1

2 Fig. 1. T1 coronal MRI view with no contrast revealing the daugh-

ter cysts within the hydatid mass. The perifocal edema is supportive of the inflammatory response caused by the pericyst. Fig. 2. Sagittal T1 MRI with no contrast showing the spherical lesion involving the daughter vesicles. Fig. 3. A, B Axial images of the right parietooccipital lesion disclosing the detached germinative membrane in T2 noncontrast (A) and ventricular compression in T1 noncontrast sequences (B). C Surgical specimen showing the unruptured hydatid cyst and the stripped pericyst after total evacuation.

384

Pediatr Neurosurg 2006;42:383–386

3

Önal/Erguvan-Önal/Yakinci/Karayol/ Atambay/Daldal

6

4

Fig. 4. Noncontrast CT of the abdomen presenting the contours of the hydatid cyst in the right kidney. Fig. 5. Noncontrast CT of the patient 6 months after the hydatid cyst removal disclosing the enlarged ventricles and the porencephalic cyst at the operative site. Fig. 6. Postoperative noncontrast CT of the patient revealing persistent porencephalic cyst with relieved intraluminal tension.

5

Discussion

Progression of hydrocephalus after spontaneous or intraoperative rupture of a hydatid cyst into the ventricular system is reported [1]. In a series of 30 pediatric cases, only 1 case with intraoperative rupture into the ventricular system required a shunt with dismal prognosis [1]. The incidence of hydrocephalus after intact removal is unknown.

Requirement of a Diversion Procedure after Intracranial Hydatid Cyst Surgery

The pathogenesis of daughter vesicles is correlated with a mechanical, chemical or a bacterial damage, though the exact mechanism is still unknown [7]. There are three layers of a hydatid – an inner germinal layer, an ectocyst composed of an eosinophilic laminated cuticle or the socalled cuticular layer, and a variable outer pericyst. The intracystic pressure normally prevents the detachment of the germinative membrane from the cyst wall. A detached

Pediatr Neurosurg 2006;42:383–386

385

germinative membrane implies a cyst wall rupture with resultant low intracystic pressure or leakage of intracystic fluid without an anatomical break down [8–10]. The thick layer surrounding the hydatid cyst called ‘pericyst’ encountered during surgery can be evaluated as the response of the host to this pathological process [7]. The pericyst and the evolved gliotic reaction limiting the mass cavity restrict the elasticity of the neural tissue with a resultant permanent porencephalic cavity having high intraluminal pressure. Peter et al. [10] in their review reported that the degree of inflammatory response in the surrounding adventitia (pericyst) may be responsible for both the enhancement characteristics and surgical difficulties experienced in some patients. Ectocystic or the cuticular layer is transparent in the early phases of development with little inflammatory exudate between it and the surrounding brain [10]. Hydraulic dissection and intact birth of a hydatid is easiest at this stage due to the ignorable adhesions. With time, an inflammatory response may be triggered by the

cuticular layer resulting in a fibrovascular adventitia surrounding the cyst. This may explain the enhancement on radiological examinations and intraoperative difficulty of in toto removal in some of the cases. Peter et al. [10] declared that degeneration of ectocyst with age or minor trauma causing leakage of allergenic material may explain this progress and some of their histological specimens revealed some clues supporting this idea. Our surgical experience with the presented case confirms this theory. The firm pericyst closely attached to the surrounding neural tissue made hydraulic dissection nearly impossible during surgery. It can be concluded that those cases with thick pericyst formation and peripheral gliotic reaction either due to the cyst wall rupture or spontaneous leakage may trigger the formation of a porencephalic cyst with a mass effect. The intracranial cases with firm pericyst formation or with detached germinative membrane should closely be followed up for a possible requirement of a diversion procedure.

References 1 Onal C, Unal F, Barlas O, Izgi N, Hepgul K, Turantan MI, Canbolat A, Turker K, Bayindir C, Gokay HK, Kaya U: Long-term follow-up and results of thirty pediatric intracranial hydatid cysts: half a century of experience in the Department of Neurosurgery of the School of Medicine at the University of Istanbul (1952– 2001). Pediatr Neurosurg 2001;35:72–81. 2 Onal C, Barlas O, Orakdogen M, Hepgul K, Izgi N, Unal F: Three unusual cases of intracranial hydatid cyst in the pediatric age group. Pediatr Neurosurg 1997;26:208–213. 3 Onal C, Yakinci C, Erten F, Erguvan R, Cayli S, Gül A, Aydin E: Supratentorial hydatid cyst with cerebellar signs: a rare case of diaschisis. Childs Nerv Syst 2001;17:746–749.

386

4 Onal C, Erguvan R: Gigantic intracranial mass of hydatid cyst. Childs Nerv Syst 2002;18:199– 200. 5 Canbolat A, Onal C, Kaya U, Coban TE: Intracranial extradural hydatid cysts: report of three cases. Surg Neurol 1994;41:230–234. 6 Erguvan-Onal R, Onal C: Intracranial hydatid cyst: can we prevent misdiagnosis? Pediatr Infect Dis J 2005;24:285–286. 7 Aksungur EH, Oguz M, Bicakci K, Altay M: Cerebral hydatid lesion with daughter cysts: MR and CT findings. AJR 1994; 163: 1269– 1270.

Pediatr Neurosurg 2006;42:383–386

8 Gomori JM, Cohen D, Eyd A, Pomeranz S: Water-lily sign in CT of cerebral hydatid disease: A case report. Neuroradiology 1988; 30: 358. 9 Aydin NE, Ege E, Selcuk MA, Erguvan R: Echinococcal hydatid cyst at the right ventricle outlet with leakage to the pulmonary artery outflow causing follicular airway disease and sudden death. Am J Forensic Med Pathol 2001;22:165–168. 10 Peter JC, Domingo Z, Sinclair-Smith C, de Villiers JC: Hydatid infestation of the brain: difficulties with computed tomography diagnosis and surgical treatment. Pediatr Neurosurg 1994;20:78–83.

Önal/Erguvan-Önal/Yakinci/Karayol/ Atambay/Daldal

Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.

Suggest Documents