Tesis

Kesesuaian Teknik Pengukuran Nilai Apparent Diffusion Coefficient (ADC) Edema Peritumoral dengan Hasil Pemeriksaan Histopatologi pada High Grade Glioma dan Metastasis Otak = Diagnostic Compatibility Study between Measurement Technique of Apparent Diffusion Coefficient (ADC) in Peritumoral Edema with Histopatologic Examination in High Grade Glioma and Brain Metastasis.

High grade glioma dan metastasis otak soliter sulit dibedakan dari gambaran morfologi MRI konvensional saja. Dua teknik pengukuran apparent diffusion coefficient (ADC) edema peritumoral yaitu teknik ADC minimal dan teknik gradien ADC dapat membedakan high grade glioma dan metastasis otak berdasarkan sifat high grade glioma yang infiltratif. Penelitian ini bertujuan menilai korelasi antara kedua teknik pengukuran tersebut dan menguji kesesuaian antara teknik pengukuran ADC edema peritumoral dengan hasil pemeriksaan histopatologi. Penelitian ini merupakan studi cross sectional dengan menggunakan data sekunder dari Rumah Sakit Cipto Mangunkusumo dan Rumah Sakit Dharmais Pusat Kanker Nasional. Sebanyak 35 subjek, 20 dengan high grade glioma dan 15 dengan metastasis, menjalani pemeriksaan MRI kepala dengan kontras. Analisis data dilakukan dalam dua tahap. Tahap pertama menilai korelasi antara teknik ADC minimal dan gradien ADC pada kelompok high grade glioma. Kemudian dipilih salah satu teknik pengukuran yang akan dipakai pada tahap kedua. Tahap kedua mengerjakan pengukuran ADC edema peritumoral pada kelompok metastasis memakai satu teknik yang dipilih dan selanjutnya menguji kesesuaian antara teknik tersebut dengan histopatologi. Koefisien korelasi antara nilai ADC minimal dan gradien ADC edema peritumoral pada high grade glioma adalah -0,163. Teknik ADC minimal digunakan di tahap kedua dan didapatkan rerata ADC minimal edema peritumoral high grade glioma (1,211 x 10 -3 mm 2 /s) secara signifikan lebih rendah daripada metastasis (1,348 x 10 mm 2 /s). Berdasarkan analisis kurva receiver operating characteristic (ROC), didapatkan nilai titik potong 1,250 x 10 vii -3 mm 2 /s. Menggunakan titik potong tersebut, dilakukan uji McNemar dengan hasil p= 0,727 dan nilai r (Kappa Cohen) 0,54. Penelitian ini memperoleh hasil adanya korelasi negatif sangat lemah antara nilai ADC minimal dan gradien ADC edema peritumoral. Terdapat kesesuaian yang cukup antara teknik ADC minimal edema peritumoral dengan histopatologi dalam mendiagnosis high grade glioma dan metastasis.
Kata kunci: apparent diffusion coefficient, high grade glioma, metastasis otak, edema peritumoral


High grade glioma and solitary brain metastasis are difficult to distinguish based on conventional MRI morphology alone. Two measurement techniques of apparent diffusion coefficient (ADC) in peritumoral edema, i.e. minimum ADC and ADC gradient, can distinguish high grade glioma from brain metastases based on infiltrative feature of high grade glioma. This study aimed to assess the correlation between the two measurement techniques and examine the compatibility between measurement technique of ADC in peritumoral edema and histopathologic examination. This research was a cross sectional study using secondary data from Cipto Mangunkusumo Hospital and Dharmais Hospital National Cancer Center. A total of 35 subjects, 20 with high grade glioma and 15 with metastasis, underwent brain MRI examination with contrast. Data analysis was done in two stages. The first stage assessed the correlation between minimum ADC and ADC gradient in high grade glioma group only. One of the two measurement techniques was selected and used in the second stage. The second stage performed measurement in the metastasis group only and then tested the compatibility between the chosen technique with histopathology examination. The correlation coefficient between minimum ADC and ADC gradient in the high grade glioma group was -0.163. Minimum ADC technique was used in the second stage. The mean minimum ADC value in peritumoral edema of high grade glioma (1.211 x 10 -3 mm 2 /s) was significantly lower than those in metastasis (1.348 x 10 mm 2 /s). According to receiver operating characteristic (ROC) curve analysis, a cut-off point of 1.250 x 10 -3 mm 2 /s was obtained and used furthermore to do McNemar test (p = 0.727; R = 0.54). This study obtained the result of a very weak negative correlation between minimum ADC and ADC gradient in peritumoral edema. There was sufficient compatibility between the minimum ADC technique with histopathology examination in diagnosing high grade glioma and brain metastasis.
Keywords: apparent diffusion coefficient, high grade glioma, brain metastasis, peritumoral edema