Original Article

DIAGNOSTIC ACCURACY OF MAGNETIC RESONANCE IMAGING FOR LOCALIZING TESTES IN CASES OF CRYPTORCHIDISM

ABDUS SAMI QAZI1, ESHA HABIB2 1 Department, PGMI / General 2Radiology Department, PGMI / Lahore General Hospital For correspondence: Dr. Abdus Sami Qazi, Radiology Department, PGMI / Lahore General Hospital, Lahore

ABSTRACT Aim: The aim of this study was to determine the diagnostic accuracy of MRI for localization of undescended testes in clinically detected cases of cryptorchidism taking surgical findings as gold standard. Material and Methods: The study was conducted in the Department of Diagnostic Radiology, Lahore General Hospital, Lahore. All patients who were included in the study were Boys within the age bracket of 0-16 years who attended out patient department (OPD) from January 2010 to December 2012 with undescended testes. Detailed relevant history and physical examination findings were recorded in all the cases. MRI of the pelvis and abdomen was performed using 1.5 Tesla MR System. Standard MR imaging techniques included axial, sagittal and coronal images on T-1, T-2 and Fat Suppression sequence. Later on laparotomy was performed to confirm MRI findings. Results: A total of 170 clinically diagnosed cases of undescended testis were registered during this period. The highest number of patients were aged between 6-11 years i.e. 79 (46.5%).Out of the 170 cases, testes of 143 patients (84.1%)were localized, of which 84 patients (49.4%)had undescended testes in the inguinal canal, 33 patients (19.4%) had undescended testes in the pre-scrotal area,12 patients (7.1%)had undescended testes in the abdomen, 10 patients (5.9%) had undescended testes localized in the scrotal sac, 4 patients(2.4%) had undescended testes in the pelvis, while testes of 27 patients (15.8%)were not localized on MRI. On comparison of results of MRI with surgery taken as gold standard, the sensitivity of MRI was 97.2%, specificity 92%, diagnostic accuracy 96.5%, positive predictive value 98.6% and negative predictive value was 85.2%.Conclusion: We recommend MRI as an accurate imaging modality for localization of the undescended testis because it has better resolution, multiplanar capability, and is also non invasive, non hazardous and safe. Moreover MRI is valuable for providing surgeons the exact location of testes.

Keywords: Cryptorchidism, Magnetic resonance imaging.

INTRODUCTION ultimately required, there is a defined role for diagnostic Cryptorchidism is the absence of one or both testes in imaging. Accurate diagnosis and appropriate treatment the scrotum and is generally synonymous with leads to the highest chance of proper testicular function undescended testes1. In approximately 4% of patients, in an endocrine capacity that is with regard to fertility; the undescended testis is nonpalpable because it is intra in addition, accurate diagnosis can facilitate early abdominal or intra canalicular or possibly atrophic or detection of malignant tumour5, 6. Preoperative absent2, 3. With undescended testis, the major localization of testis also aids in the planned surgical abnormalities include prune-belly syndrome, spina approach, reducing the extent of exploration and bifida and posterior urethral valves. Incidental and time. isolated findings include cases of duplex system, horseshoe kidney and solitary kidney. As urinary and MATERIAL AND METHODS genital systems originate in the intermediate mesoderm, The study was conducted in the department of renal agenesis may be associated with ipsilateral Diagnostic Radiology, Lahore General Hospital, urogenital anomalies4. Lahore. The study group comprised of all boys with Undescended testes that are non-palpable and non-palpable undescended testes between 0-16 years located high up are more likely to have associated age attending the OPD of Lahore General Hospital epididymal anomalies causing obstruction to the sperm (LGH), Lahore from January 2010 to December 2012 conducting pathway. The most problematic aspect of who were referred by the clinician for imaging and the undescended testes is the diagnosis and management of cases in which ultrasound or CT had failed to localize nonpalpable testes. Although surgical intervention is testes either in scrotal sac, in inguinal canal or along the

PAKISTAN POSTGRADUATE MEDICAL JOURNAL Vol. 23 No. 3 Jul. – Sept. 2012 69 ABDUS SAMI QAZI, ESHA HABIB normal route of migration. A careful and detailed were true positive, 23 patients were true negative; 02 history was obtained and the presence of undescended patients were false positive and 04 patient were false testis was documented. The basic demographic negative. information(age) was recorded and hospital ethical The sensitivity of MRI was 97.2%, specificity 92%, committee was appraised. As there were no radiation diagnostic accuracy 96.5%, positive predictive value hazards and all patients were selected on clinical 98.6% and negative predictive value was 85.2%. grounds so no ethical issue was involved. MRI of all cases at 1.5 Tesla MR System(Philips Gyro Scan NT, DISCUSSION Compact Plus, Holland) was performed. Standard MR Cryptorchidism is the term used when the testis is not imaging techniques included axial and coronal images present in the scrotal sac. Incidence of maldescended on T-1, T-2 and Fat Suppression sequences. MRI testis is up to 20%7.The age of presentation ranged findings were recorded as testes localized/ not localized, between 0 to 16 years. The maximum number of if localized whether in the sac, pre-scrotal area, inguinal patients in our study was in the age group of 6-11 years canal, pelvis or abdomen. MRI findings were compared i.e. 79 (46.5%), followed by age group 0-5 years (53 with surgical findings as reference standard because patients i.e. 31.2%) and age group 12-16 years (38 surgery was done in all cases to avoid neoplastic patients i.e. 22.3%) which is in agreement with transformation. The information was recorded on a literature findings which state that a lower prevalence of prepared proforma. Informed consent was obtained 1–2% is in age from 3 to 12 months of life while in two from the patients/parents. school surveys of pre-pubertal boys prevalence rates up to 7% were reported8,9 . In our study, out of 170 patients RESULTS of cryptorchidism, testes were localized in inguinal A total of 170 boys of undescended testis were studied canal in 84 patients (49.4%), This is in accordance with during this period of 3 years. In our study, out of 170 a previous study10 which revealed that in cases of cases, we found that the highest number of patients cryptorchidism testes were identified in intra- were aged between 6-11 years i.e. 79 (46.5%), 53 canalicular locations in 50.0% of patients. Our study patients (31.2%) were aged between 0-5 years and 38 also agrees with another study11 which reported the patients (22.3%) were aged between 12-16 years. Out of commonest location for cryptorchid testicles was within 170 patients, testes of 143 patients (84.1%) were inguinal canal 53.3%. Another study also proved most localized on MRI while testes of 27 patients (15.9%) common location of cryptorchid testis is in the inguinal were not localized on MRI. canal (72%), followed by prescrotal (20%) and Out of 170 patients, testes of 145 patients (85.3%) abdominal (8%)12. In our study, on comparison of were localized on surgery while 25 patients (14.7%) results of MRI with surgery taken as gold standard, out were not localized on surgery. of 170 patients, 141 patients were true positive, 23 Out of the 170 patients, testes of 143 patients patients were true negative; 02 patients were false (84.1%)were localized , of which 84 patients positive and 04 patients were false negative. The overall (49.4%)had undescended testes in the inguinal canal , sensitivity of MRI was 97.2%, positive predictive value 33 patients (19.4%) had undescended testes in the pre- 98.6% and negative predictive value 85.2% and scrotal area, 12 patients (7.1%)had undescended testes diagnostic accuracy 96.5%, which is supported by study in the abdomen, 10 patients (5.9%) had undescended of Kanemoto et al13.who used MRI for the diagnosis of testes localized in the scrotal sac, , 4 patients(2.4%) had non palpable testis and found that MRI can be expected undescended testes in the pelvis, while testes of 27 to have sensitivity of 86% and an accuracy of 85%.Our patients (15.8%)were not localized on MRI. study proved specificity 92% which lies close to study Out of the 170 patients, testes of 145 patients by Sarihan et al14 who found that MRI had specificity of (85.3%)were localized , of which 86 patients 100% in the detection of non palpable undescended (50.6%)had undescended testes in the inguinal canal , testis. Another study by Mona et al15also supports our 31 patients (18.2%) had undescended testes in the pre- results which revealed that MRI sensitivity is 100%, scrotal area, 13 patients (7.6%)had undescended testes specificity 83% & accuracy 95%. in the abdomen, 11 patients (6.5%) had undescended testes localized in the scrotal sac, 4 patients(2.4%) had CONCLUSION undescended testes in the pelvis, while testes of 25 Magnetic resonance imaging is a highly accurate, non patients (14.7%)were not localized on surgery. invasive technique and offers a new promising imaging On comparison of results of MRI with surgery modality for localization of the undescended testicles taken as gold standard, out of 170 patients,141 patients because it has better resolution, multiplanar capability,

70 Vol. 23 No. 3 Jul. – Sept. 2012 POSTGRADUATE MEDICAL JOURNAL DIAGNOSTIC ACCURACY OF MAGNETIC RESONANCE IMAGING FOR LOCALIZING TESTES IN CASES OF different sequences and is also non hazardous and safe. 7. Shah A, Shah A. Impalpable Testes-Is Imaging Also MRI with IV Gadolinium contrast injection is also Really helpful? Indian 2006;43:720-3. helpful in cases of atrophied testes which are not 8. Blom K. Undescended testis and time of detectable by any other modalitiy. MRI is valuable for spontaneous descent in 2516 schoolboys. Ugeskr guiding surgeons the exact location of testes thereby Laeger 1984; 146: 616–7. decreasing unnecessary large incisions in laparotomy 9. Simpson AS, Laugesen M, Silva PA, Stewart C, and preventing complications associated with Walton J. The prevalence of retained testis in undescended testes like infertility and neoplastic Dunedin. NZMedJ 1985; 98:758–60. transformation. 10. Kantarci M, Doganay S, Yalcin A, Aksoy Y, Yilmaz-Cankaya B, Salman B. Diagnostic REFERENCES Performance of Diffusion-Weighted MRI in the 1. Williams EV, Appanna T, Foster ME, et al. Detection of Nonpalpable Undescended Testes: Management of the impalpable testis: a six year Comparison With Conventional MRI and Surgical review together with a national experience. Findings. AJR AM J Roentgenol. 2010 oct; Postgrad Med J 2001; 77:320-322. 195(4):W268-73. 2. Fritzsche PJ, H, Kogan BA, et al. Undescended 11. Adel A Shehata! & Osama M. MRI Versus testis: value of MR imaging. Radiology 1987; 164- Ultrasound In Localization of Undescended 173. Testicles. Suez Canal Univ Med J 2003;6: 291-300. 3. Kogan SJ. Cryptorchidism. In: kelalis PP, King LR, 12. Dogra VS, Mojibian H, Haddad JL et al: Gelman AB, eds. Clinical pediatric , 2nd ed. Cryptorchidism eMedicine. Microsoft internet Philadelphia, PA: Saunders, 1985:864-887. explorer 2002; Vol 21,Page 2 of7. 4. Cascio S, Paran S, Puri P. Associated urologic 13. Kanemoto K, Hayashi Y, Kojima Y, Maruyama T, anomalies in children with unilateral renal agenesis. Ito M, Kohri K. Accuracy of ultrasonography and J Urol 1999;162:1081-3. magnetic resonance imaging in diagnosis of non- 5. Kucheria R, Sahai A, Sami TA, et al. Laproscopic palpable testis. International journal of urology management of cryptorchidism in adults. Eur Urol 2005;12:668-72. 2005; 48;453-457. 14. Sarihan H, Sari A, Abeş M, et al. Nonpalpable 6. Chew G, Hutson JM. Incidence of cryptorchidism undescended testis: value of magnetic resonance and ascending testes in trisomy 21: a 10 year imaging. Minerva Urol Nefrol 1998; 50:233–236. retrospective review. Pediatr Surg Int 2004; 20:744- 15. Mona NA, Ahmed BF. Ultrasound Versus MRI in 747. Localization of Undescended Testes. Radiology 1999.

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