DIAGNOZA TIMPURIE A ADENOMULUI DE HIPOFIZA

Abstract

Pituitary adenomas represent approximatetelyl0% of intracranial tumors. Like tumors of other endocrine glands, pituitary adenomas vary considerably in size, growth rate, radiological appearance, clinical presentations, endocrine function cellular composition, and morphology. Neurosurgeons frequently classify pituitary adenomas according to their size. Classification of pituitary adenomas by radiographic appearance is most useful [PUBLICATION ABSTRACT]

Rodica MARINESCU1

Viorica LEFTER2,

Magdalena MOROJANU3

Paul ICHIM3

1 Spitalul Clinic de UrgenÇa GalaÇi

2 BTF "LACU SÄRAT"

3 Spitalul Clinic de Urgenza Galati

Cuvinte cheie: diagnoza, adenom de hipofizä

Rezumat

Adenomul hipofizar reprezinta aproximativ 10% din tumorile intracraniene. Ca si alte tumori ale glandelor endocrine prezinta variatii mari in ceea ce priveste marimea, ritmul de crestere, aspectul radiologie, fórmele clinice si tipul morfologie.

Este o tumora benigna a carei extirpare totala depinde de buna colaborare intre neurochirurg, neurology, endoerinolog si neuroradiolog. In cadrul evaluarii preoperatorii au o deosebita importanta concluziile examenului radiologie, care va trebui sa ofere date cat mai precise privind marimea si extinderea tumorii.

Introducere

Adenoamele de hipofizä se dezvoltä ca o leziune intraparenchimalä la nivelul lobului anterior. Ele pot fi clasifícate în funche de dimensiuni, tip de hormón secretai sau ìn funere histoligia acestuia.

Inicial, acestea apar ca conglomerate microscopie de celule tumorale aranjate in foije uniforme, celule poligonale farà aderente celulare distinct. O tumorä mai mica de 10 mm în diametru este numitä microadenom si este de obicei localizat în saua turceaseä. Aceste adenoame microscopic se întâlnesc la 20% din examinärile postmortem de rutina. Un macroadenom este o tumorä mai mare de 10 mm diametru si depäseste de obicei saua turceaseä în sus cätre hipotalamus si chiasma, în jos spre sinusul sfenoid si lateral spre sinusurile cavernoase. Tinând cont de hormonii secretaci de tumori prolactinele si ACTH sunt secretate de obicei de microadenoamele localízate eel mai des laterala de hipofizä. Adenoamele cu secrete de GH si nonsecretorii sunt de obicei macroadenoamele. Adenoamele cu alte secreti ca TSH, FSH sau LH sunt foarte rare.

Clasiflcarca adenoamelor de hipofizä în functie de imaginea radiografica

Grad.1 Adenom intrahipofizar eu diametru mai mie de 1 cm, sa normal, modificali minime de configurale

Grad.2 Adenom intrasellar, diametru mai mare de 1 cm, sa largita farà eroziuni

Grad.3 Adenom difuz, sa marita cu eroziuni localízate

Grad.4 Adenom invaziv cu distrugeri osoase extinse.

Macroadenomul de hipofizä este identificat pe baza analizelor CT si RMN. Cu acestea douä metode protocolul de diagnostic cere imagini directe, in felii sutyiri, cu si farà substanjä de contrast. RMN-ul este de asemenea efectuat si în plan sagital.

Pe imaginea CT microadenomul apare ca un nodul usor hipodens de cativa mm în diametru în interiorul hipofizei. Microadenomul este mai usor de observât cu substanjä de contrast.

Imaginile RMN, sunt mult mai evidente în cazul microadenomului dupä injectare cu ïadolinium deoarece apare hipointens în zona hiperintensä a hipofizei

Radiologie, imaginile arata o sa extinsä cu eroziuni si dispersii catre sinusul sphenoid. CT-ul arata aceleasi modificari osoase în timp ce RMN-ul arata mai bine implicatile structurilor ìnvecinate. De asemenea angiografia si cisternografia poate aduce informagli suplimentare privind dimensiunile si interesärile altor fesuturi ìnvecinate.

Concluzii

* clasificarea adenoamelor de hipofizä dupä aspectul radiografie este foarte util neurochirurgilor

* abordarea transsfenoidalä reprezintä o ob^iune importantä în tratamentul adenoamelor hipofizare

* pentru succesul procedurii neurochirurgicale este necesarä o evaluare radiografica preoperatorie minujioasä.

Bibliografìe

1. Apuzzo Michael LJ-Brain surgery-complication avoidance and management - Wiliams & Wilkins, 1995;

2. Danaila L.-Tratamentul tumorilor cerebrale- Editura Academiei, Bucuresti, 1 993 ;

3. Kaye Andrew H. and Black Peter McL-Operative Neurosurgery- Harcourt Publisher Limited, 2000;

4. Sekhar Laligam. N and Janecka Ivo P.- Surgery of Cranial Base Tumors- Raven Press, 1993;

5. Scotti G. and Hermans R.-Neuroradiology and Head and Neck Imaging- NICER Institute, 2000;

6. Wilkins Robert H. and Rengachary Setti S.- Neurosurgery- Me. Graw-Hill Book Copmany, 1993.

THE EARLY DIAGNOSIS IN PITUITARY ADENOMA

Rodica MARINESCU1

Viorica LEFTER2,

Magdalena MOROJANU3

Paul ICHIM3

1 "The County Hospital Galati"

2 BFT "Lacu Sarat"

3 "The County Hospital Galati"

Keywords: diagnosis, pituitary adenoma

Abstract

Pituitary adenomas represent approximatetelyl0% of intracranial tumors. Like tumors of other endocrine glands, pituitary adenomas vary considerably in size, growth rate, radiological appearance, clinical presentations, endocrine function cellular composition, and morphology.

Neurosurgeons frequently classify pituitary adenomas according to their size. Classification of pituitary adenomas by radiographic appearance is most useful

Introduction

Pituitary adenomas develop as intraparenchymal lesions of the anterior lobe. They may be classified according to size, type of hormone secreted or to histological staining with specific dyes.

Initially, they consist of a microscopic conglomerate of tumor cells arranged in sheets of uniform, polygonal cells with indistinct cell boundaries. A tumor of less 10mm in diameter is called a microadenoma and is usually confined within the sella turcica. These microscopic adenomas can be found in approximately 20% of routine, postmortem examinations. A macroadenoma is a tumor of more than 10mm in diameter and ussualy extends beyond the confines of the sella turcica, upward the chiasm and hypothalamus, downward toward the sphenoid sinus and laterally toward the cavernous sinuses. With regard to the hormone secreted, prolactinomas and ACTH-secreting tumours are usually microadenomas, located most commonly in a lateral position within the pituitary gland. GH- secreting adenomas and nonsecreting tumours are usually macroadenomas. Other secreting tumours like TSH-, FSH-, or LH- secreting adenomas are very rare.

Clasifkation of pituitary adenomas according to radiographic appearance

Grade 1 Intrapituitary adenoma; diameter < 1cm; normal sella; minimal configurational changes

Grade 2 Intrasellar adenoma; diameter > 1cm; enlarged sella; no erosion

Grade 3 Diffuse adenoma; enlarged sella; localized sellar erosion

Grade 4 Invasive adenoma; extensive destruction of bony structures "ghost" sella

Neuroradiological diagnosis

Microadenoma pituitary , the diagnosis is based on CT and RM findings. With both modalities the diagnostic protocol requires diect coronal images, thin slices, without and with contrast. MR is also performed in the sagital plane.

The CT appearance of a microadenoma is that of iso- or slightly hypodense nodule of few mm in diameter within the pituitary gland. The microadenoma is better seen after contrast injection since the pituitary tissue enhances, due to the absence of blood-brain barrier while the adenoma remains hypodense.

Radiologically, plain films usually show an expanded sella with erosion and depression of the sellar floor toward the sphenoid sinus.

CT shows the same bony changes and the mass lesion, usually isodense, with marked enhancement.

MR better shows involvement of the surrounding structures with elevation of the chiasm, compression and invasion of the cavernous sinuses and encasement of the carotid siphon. The tumor is usually isointense on TI, with marked enhancement after gadolinium injection. Sometimes, haemorragic and cystic components are present.

Also with the angiography and cisternography the size of the tumor and its spread into neighboring can be conclusively assessed.

Conclusions

- classification of pituitary adenomas by radiographic appearance is more useful for the neurosurgeon;

- the transsphenoidal approach is procedure of choice in the operative treatment of most pituitary adenomas;

- for the success of a neurosurgical procedure is necessary a preoperative evaluation that includes a radiological study of sellar and parasellar anatomy.