RADIOGRAFI KONVENSIONAL

Radiografi konvensional meliputi radiografi abdomen polos, urografi ekskretori

intravena, pielografi retrograde, loopografi, uretrografi retrograde, dan sistografi.

FISIKA

Radiografi konvensional melibatkan emisi foton dari sumber sinar-X. Foton-foton

tersebut berjalan melewati udara dan menembus jaringan,untuk selanjutnya memberikan

energi ke jaringan tersebut. Sejumlah foton akan muncul dari pasien dengan sejumlah energi

yang dilemahkan dan menuju perekam gambar seperti kaset film, sehingga menghasilkan

gambar.

Risiko terpenting dari paparan radiasi dari pencitraan diagnostik adalah

berkembangnya kanker. Rata-rata orang yang tinggal di Amerika Serikat terpapar 1-3 mSv

radiasi per tahun. Batasan paparan okupasi yang direkomendasikan bagi tenaga medis adalah

50 mSv per tahun (NCRP, 1993). Paparan pada mata dan gonad menyebabkan dampak

biologis yang lebih bermakna dibandingkan paparan terhadap ekstremitas, sehingga batasan

paparan yang direkomendasikan beragam tergantung bagian tubuh yang terkena.

Bagaimanapun tidak ada dosis radiasi yang aman. Dosis radiasi sebesar 10 mSv saja bisa

menyebabkan berkembangnya keganasan pada 1 dari 1000 orang yyang terpapar (NRCNA,

2006).

Pengurangan paparan radiasi terhadap petugas medis bisa dicapai melalui 3 hal, yaitu

(1) membatasi waktu paparan, (2) memaksimalkan jarak dari sumber radiasi, dan (3)

menggunakan pelindung.

MEDIA KONTRAS

Media Kontras Intravaskular Teriodinasi

Iodine adalah elemen yang paling sering digunakan sebagai media kontras radiologis.

Dengan berat atom 127, iodine memiliki radioopasitas, sementara media yang lainnya tidak

dan hanya berperan sebagai pembawa elemen iodine, meningkatkan kelarutan dan

menurunkan toksisitas.

Empat tipe dasar media kontras intravaskular teriodinasi yang tersedia untuk penggunaan

klinis, yaitu monomer ionik, monomer nonionik, ionik dimer, dan dimer nonionik. Media ini

lebih jauh dikategorikan sebagai iso-, hiper-, atau hipo-osmolar.

Reaksi yang Tidak Diinginkan dari Media Kontras Intravaskular Teriodinasi

Reaksi Minor

Reaksi berupa mual, kulit kemerahan, gatal, bruntus-bruntus, nyeri kepala, dan

muntah setelah injeksi kontras. Reaksi ini biasanya ringan dan tidak membutuhkan tambahn

terapi. Bloker reseptor H1 seperti difenhidramin 1-2 mg/kg sampai 50 mg bisa membantu.

Reaksi Intermedia

Merupakan reaksi ringan yang memburuk disertai hipotensi atau bronkhospasme.

Biasanya bersifat sementara dan tidak membutuhkan terapi. Juka diperlukan, 4-10 mg

chlorphenamin secara oral, intravena, atau intramuskular; diazepam 5 mg untuk mengatasi

kecemasan; hydrocortisone 100-500 mg intramuskular atau intravena; atau beta-agonis

inhalator untuk bronkhospasme.

Reaksi Berat

Reaksi ini meliputi kejang, spasme laring, bronkhospasme, edema paru, aritmia

jantung, gagal napas, atau henti jantung. Jika diperlukan, resusitasi jantung-paru bisa dimulai

segera. Pemberian segera epinefrin adalah pilihan terapi untuk reaksi yang berat. Terapi

terkini menyarankan pemberian segera dari epinefrin 1:1000 sebanyak 0,01 mg/kg berat

badan sampai dosis maksimal 0,5 mg, diinjeksikan ke paha bagian lateral sebagai terapi lini

pertama.

Strategi Premedikasi

Tidak ada strategi premedikasi yang diketahui bisa mengeliminasi risiko munculnya

reaksi yang tidak diinginkan. Akan tetapi, kortikosteroid, antihistamin, H1 dan H2 antagonis,

dan epinefrin bisa disarankan.

Agen Kontras MRI

Agen kontras ekstraselular untuk MRI mengandung ion metal paramagnetik.

Tembaga, mangan, dan gadoliniium adalah ion paramagnetik yang potensial untuk digunakan

bersama MRI.

UROGRAFI INTRAVENA

Teknik

Kebanyakan pasien hanya membutuhkan cairan jernih selama 12 jam dan enema 1

jam sebelum prosedur sebagai persiapan usus. Pasien dengan konstipasi kronis membutuhkan

12-24 jam pemberian cairan jernih dan enema 2 jam sebelum prosedur. Sebelum penyuntikan

kontras, diambil foto KUB (kidney, ureters, bladder) untuk memastikan persiapan usus sudah

cukup, mengonfirmasi posisi yang tepat, dan untuk memperlihatkan adanya batu ginjal atau

batu kandung kemih.

Kontras diinjeksikan secara bolus intravena sebanyak 50-100 ml. Fase nefrogenik

difoto segera setelah injeksi. Foto setelah 5 menit dan tambahan foto setiap interval 5 menit

diambil. Kompresi abdomen bisa digunakan untuk mendapatkan gambar ureter yang lebih

jelas. Terkadang pengambilan foto secara oblique akan berguna untuk melihat perjalanan

ureter pada tulang pelvis dan bisa membedakan antara batu ureter atau kalsifikasi tulang

pelvis. Foto pasca-berkemih diambil untuk mengevaluasi adanya obstruksi pintu keluar,

pembesaran prostat, defek pengisian kandung kemih termasuk batu dan kanker saluran

kencing.

Indikasi

1. Memperlihatkan sistem kolekting ginjal dan ureter.

2. Mencari level obstruksi ureter.

3. Menunjukkan adanya opasifikasi intraoperatif dari sistem kolekting selama prosedur

ESWL atau akses perkutan menuju sistem kolekting.

4. Memperlihatkan fungsi ginjal dari pasien yang tidak stabil.

5. Memperlihatkan anatomi ginjal dan ureter pada keadaan tertentu (ptosis, setelah

transureterouretrostomi, setelah diversi saluran kencing).

RADIOGRAFI ABDOMEN POLOS

The plain abdominal radiograph is a conventional radiography study, which, in urology, is

intended to display the kidneys, ureters and bladder. Plain radiography is also useful in

evalua- tion of the trauma patient. Secondary findings on plain radiography such as pelvic

fractures may indicate serious associated urologic injuries.

Teknik

An abdominal plain radiograph is obtained with the patient in the supine position, using an

anterior to posterior exposure. The study typically includes that portion of the anatomy from

the level of the diaphragm to the inferior pubic symphysis. oblique films are obtained to

clarify the position of structures in relation to the urinary tract. If small bowel obstruction or

free peritoneal air is suspected, upright films will be obtained.

Indikasi

1. To be a preliminary film in anticipation of contrast administration

2. To assess the presence of residual contrast from a previous imaging procedure

3. To assess renal calculus disease before and after treatment

4. To assess the position of drains and stents

5. To be an adjunct to the investigation of blunt or penetrating trauma to the urinary tract

PIELOGRAFI RETROGRADE

Retrograde pyelograms are performed to opacify the ureters and intrarenal collecting system

by the retrograde injection of contrast media. Any contrast media that can be used for

excretory urogra- phy is also acceptable for retrograde pyelography. retrograde pyelography

has the unique ability to document the normalcy of the ureter distal to the level of obstruction

and to better define the extent of the ureteral abnormality.

Technique

Retrograde pyelography is usually performed with the patient in the dorsal lithotomy

position. An abdominal plain radiograph is obtained to ensure that the patient is in the appro-

priate position to evaluate the entire ureter and intrarenal collect- ing system. Cystoscopy is

performed and the ureteral orifice is identified. Contrast may be injected through either a

nonobstructing cath- eter or an obstructing catheter. Contrast can then be introduced directly

into the upper collecting system, and the ureters can be visualized by injection of contrast as

the catheter is withdrawn. Contrast is then injected to opacify the ureter and intrare- nal

collecting system. Contrast is injected slowly, usually requiring from 5 to 8 mL to completely

opacify the ureter and intrarenal collecting system in adults (Fig. 4–6).

Indications

1. Evaluation of congenital ureteral obstruction

2. Evaluation of acquired ureteral obstruction

3. Elucidation of filling defects and deformities of the ureters or intrarenal collecting systems

4. Opacification or distention of collecting system to assist percutaneous access

5. In conjunction with ureteroscopy or stent placement

6. Evaluation of hematuria

7. Surveillance of transitional cell carcinoma

8. In the evaluation of traumatic or iatrogenic injury to the ureter or collecting system

LOOPOGRAFI

Loopography is a diagnostic procedure performed in patients who have undergone urinary

diversion. may be used in reference to any bowel segment serving as a urinary conduit.

Teknik

The patient is positioned supine. An abdominal plain radiograph is obtained before the

introduction of contrast material (Fig. 4–8A). A commonly employed technique is to insert a

small-gauge catheter into the ostomy of the loop, advancing it just proximal to the abdominal

wall fascia. The balloon on such a catheter can then be inflated to 5 to 10 mL with sterile

water. By gently intro- ducing contrast through the catheter, the loop can be distended,

usually producing bilateral reflux into the upper tracts. Oblique films should be obtained in

order to evaluate the entire length of the loop (Fig. 4–8B). A drain film should be obtained

(Fig. 4–8C). This may demonstrate whether there is obstruction of the conduit.

Indications

1. Evaluation of infection, hematuria, renal insufficiency, or pain after urinary diversion

2. Surveillance of upper urinary tract for obstruction

3. Surveillance of upper urinary tract for urothelial neoplasia

4. Evaluation of the integrity of the intestinal segment or reservoir

URETROGRAFI RETROGRADE

A retrograde urethrogram is a study meant to evaluate the anterior and posterior urethra.

Retrograde urethrography may be particu- larly beneficial in demonstrating the total length of

a urethral stricture, which cannot be negotiated by cystoscopy. Retrograde urethrography also

demonstrates the anatomy of the urethra distal to a stricture, which may not be assessable by

voiding cystourethrography.

Teknik

A plain film radiograph is obtained before injection of contrast. The patient is usually

positioned slightly obliquely to allow evalu- ation of the full length of urethra. The penis is

placed on slight tension. A small catheter may be inserted into the fossa navicularis with the

balloon inflated to 2 mL with sterile water. Contrast is then introduced via catheter-tipped

syringe. Alternatively, a penile clamp (e.g., Brodney clamp) may be used to occlude the

urethra around the catheter (Fig. 4–9).

Indikasi

1. Evaluation of ureteral stricture disease

2. Assessment for foreign bodies

3. Evaluation of penile or urethral penetrating trauma

4. Evaluation of traumatic gross hematuria

SISTOGRAFI STATIS

Static cystography is employed primarily to evaluate the structural integrity of the bladder.

The shape and contour of the bladder may give information about neurogenic dysfunction or

bladder outlet obstruction. Filling defects such as tumors and stones may be appreciated.

Teknik

The patient is positioned supine. A plain radiograph is performed to evaluate for stones and

residual contrast and to confirm posi- tion and technique. The bladder is filled with 200 to

400 mL of contrast depending on bladder size and patient comfort. Adequate filling is

important to demonstrate intravesical pathology or bladder rupture. Oblique films should be

obtained because posterior diverticula or fistulae may be obscured by the full bladder. A

postdrainage film completes the study (Fig. 4–10).

Indikasi

1. Evaluation of intravesical pathology

2. Evaluation of bladder diverticula

3. Evaluation of inguinal hernia involving the bladder

4. Evaluation of colovesical or vesico-vaginal fistulae

5. Evaluation of bladder or anastomotic integrity after surgical procedure

6. Evaluation of blunt or penetrating trauma to the bladder

VOIDING CYSTOURETHROGRAM

A voiding cystourethrogram (VCUG) is performed to evaluate the anatomy and physiology

of the bladder and urethra. pediatric patients. VCUG has long been used to demonstrate vesi-

coureteral reflux.

Technique

The study may be performed with the patient supine or in a semiupright position using a table

capable of bringing the patient into the full upright position. A preliminary pelvic plain radio-

graph is obtained. In children a 5- to 8-Fr feeding tube is used to fill the bladder to the

appropriate volume. Patient comfort should be taken into account when determining the

appropriate volume. In the adult population a standard catheter may be placed and the bladder

filled to 200 to 400 mL. The catheter is removed and a film is obtained. During voiding, AP

and oblique films are obtained. The bladder neck and urethra may be evaluated by

fluoroscopy during voiding. Bilateral oblique views may demonstrate low- grade reflux,

which cannot be appreciated on the AP film. In addition, oblique films will demonstrate

bladder or urethral diver- ticula, which are not always visible in the straight AP projection.

Postvoiding films should be performed (Fig. 4–11).

Indications

1. Evaluation of structural and functional bladder outlet obstruction

2. Evaluation of reflux

3. Evaluation of the urethra in males and females