Medical2: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/Medical2 - from package: vtk-examples

You may install the required package with command yum install {package}

Error in other languages:
Medical2: bevel nie gevind nie
Medical2: comandă negăsită
Medical2: comando não encontrado
Medical2: commande introuvable
Medical2: command not found
Medical2: käsku ei ole
Medical2: không tìm thấy lệnh
Medical2: komanda nerasta
Medical2: Kommando nicht gefunden.
Medical2: kommandot finns inte
Medical2: komut yok
Medical2: nie znaleziono polecenia
Medical2: níor aimsíodh an t-ordú
Medical2: no se encontró la orden
Medical2: no s'ha trobat l'ordre
Medical2: opdracht niet gevonden
Medical2: parancs nem található
Medical2: perintah tidak ditemukan
Medical2: príkaz nenájdený
Medical2: příkaz nenalezen
Medical2: команда не найдена
Medical2: командата не е открита
Medical2: 命令找不到
Medical2: コマンドが見つかりません