Ultimo aggiornamento: Maggio 18, 2026
Another simplicity consulting in my office which is came from the health checkup program, it was a kidney stone finding coincidently. The most common imaging modality offered in health checkups is ultrasonography – easy to perform, affordable, and radiation-free. But when goes deeper at the performance, ultrasonography is just a screening tool.
Limitations of ultrasonography in kidney stone detection.
- Operator-dependent – Accuracy depends heavily on the radiologist’s experience and skill.
- High false positive rate – Ultrasound detects small kidney stones with only about 45% accuracy, and it can be difficult to distinguish true stones from calcified vessels or calcification in renal tissue.
- Difficult in obese patients – Thick adipose tissue interferes with the sound wave algorithm, reducing image quality significantly.
When a patient comes to see me, I evaluate whether a definitive investigation is needed. The gold standard is CT scan, which reaches 95% accuracy and can detect stones as small as 1.25 mm. Modern CT protocols use extremely low radiation doses – far below any hazardous level.
Do we need to remove every single kidney stone? The answer is “not every stone needs treatment.” The narrowest part of the urinary system is the ureter, which can allow stones sized at 4 mm or smaller to pass on their own without significant pain. If the stone is smaller than 4 mm, watchful observation is appropriate – no costly procedure is needed upfront.
My suggestion is to drink more than 2.5 liters of still water per day. Adequate hydration produces enough urine output to flush small stones out naturally. That said, even stones smaller than 4 mm can occasionally cause pain, so it is always best to consult your trusted urologist rather than waiting for symptoms to develop.
If a kidney stone has been found in your health checkup and you would like a proper urological evaluation, Dr. Soarawee Weerasopone offers specialist consultations at Bangkok Hospital Headquarters. Prenota una consulenza.
Frequently Asked Questions about Kidney Stone Treatment
No. Small kidney stones, particularly those 4 mm or smaller, have a good chance of passing on their own through the urinary tract without requiring intervention. Watchful waiting with increased fluid intake is the standard approach for small asymptomatic stones. Treatment is considered when stones are large, cause significant pain, block urine flow, or are associated with infection.
Ultrasound is a useful screening tool but has limitations for kidney stone detection. Its accuracy for detecting small stones is only around 45%, and it can produce false positive results by misidentifying calcified blood vessels or parenchymal calcifications as stones. A CT scan without contrast is the gold standard investigation, offering up to 95% accuracy and the ability to detect stones as small as 1.25 mm.
No. Modern CT protocols for kidney stone evaluation use an ultra-low radiation dose – far below any harmful level. The radiation exposure is minimal and considered safe for most patients. The diagnostic benefit of accurately identifying and sizing a stone far outweighs the negligible radiation risk, especially when compared to the consequences of missing or mismanaging a kidney stone.
Yes, stones 4 mm or smaller have a reasonable chance of passing naturally with adequate hydration. Drinking more than 2.5 liters of still water per day increases urine output, which helps flush stones through the urinary tract. However, even small stones can occasionally cause obstruction or pain, so urological monitoring is advisable during the observation period.
Kidney stone treatment is recommended when the stone is larger than 4–6 mm and unlikely to pass spontaneously, causes significant or persistent pain (renal colic), is associated with urinary tract infection or fever, causes urinary obstruction, or when the patient has a solitary kidney. Treatment options include shockwave lithotripsy, ureteroscopy, and percutaneous nephrolithotomy depending on stone size and location.
Disclaimer: Questo contenuto è redatto e revisionato dal Dr. Soarawee Weerasopone, urologo certificato presso il Bangkok Hospital Headquarters. È inteso solo a scopo educativo e non costituisce consulenza medica. Consultare sempre un professionista sanitario qualificato prima di iniziare qualsiasi trattamento medico.
Scritto e revisionato dal punto di vista medico da: Dr. Soarawee Weerasopon (Dr. Pom) – Urologo specialista, Ospedale Bangkok Sede Centrale. Fellowship Internazionali: Baylor College of Medicine (USA) · Juntendo University (Giappone) · Chang Gung Memorial Hospital (Taiwan).
Il Dr. Soarawee Weerasopone (Dr. Pom) è un urologo certificato presso la sede centrale dell'Ospedale di Bangkok, specializzato in Salute maschile, Chirurgia robotica (sistema Da Vinci) e trattamento dei calcoli renali. Ha completato borse di studio internazionali presso il Baylor College of Medicine (USA), il Juntendo University Hospital (Giappone) e il Chang Gung Memorial Hospital (Taiwan). Tutti i contenuti medici di questo sito sono scritti e revisionati dal Dr. Soarawee sulla base della sua esperienza clinica e formazione internazionale.
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Avevo problemi di incontinenza urinaria (vescica attiva), la mia vita era un disastro; non riuscivo a dormire per 3 settimane, perché ogni notte quando mi sdraiavo mi veniva l'urgenza, ma appena andavo in bagno... un piccolo getto e niente. Questo accadeva dalle 8 alle 10 volte a notte, con ripercussioni sulla mia salute e sul mio benessere generale, e la mia qualità di vita è scesa a livelli altissimi. Ho trovato il DrSoarawee Weerasopone su Google. Ho parlato con il dottore, che ha ascoltato pazientemente i miei problemi e mi ha dato una risposta. Mi ha chiesto di venire a fare degli esami. 3 settimane dopo il mio sistema o i miei disturbi sono scomparsi.
Raccomando vivamente il dottor Soarawee... Se avete problemi di incontinenza urinaria, si siederà e vi ascolterà davvero, e ha una grande personalità.
Grazie mille, amico mio