The microscopic appearance of Magnesium Ammonium Phosphate (Struvite) is

Correct Answer: B

Rationale: Struvite (magnesium ammonium phosphate) crystals appear rectangular (coffin-lid shape) under microscopy classic infection stone marker (e.g., urease bacteria). Needle-shaped fits urate or cystine wrong chemistry. Amorphous lacks distinct form, unlike struvite's structure too vague. Hourglass isn't typical confuses with other forms. Rectangular morphology distinguishes struvite, key to identifying infection-driven stones, unlike sharp, shapeless, or misattributed shapes.

Correct Answer: C

Rationale: Columns of Bertin are cortical extensions between medullary pyramids structural dividers, not medullary. Pyramid apex is papillary urine exit. Medullary extensions are pyramids themselves wrong tissue. Conical areas are pyramids, not columns shape error. Cortical columns distinguish them, key to renal architecture, unlike medullary or conical misplacements.

Correct Answer: D

Rationale: Urge incontinence is treated medically first antimuscarinics or β3-agonists calm detrusor overactivity, addressing urgency. Stress incontinence (leak with pressure) often needs surgery pelvic support issue. Continuous suggests fistula surgical. Overflow (retention) may need catheterization obstruction-based. Urge's detrusor focus distinguishes it, key to initial medical management, unlike structural or retention types.

Correct Answer: A

Rationale: Detrusor overactivity (DO) is diagnosed by involuntary contractions during filling any size, reflecting bladder instability (e.g., urge incontinence). Amplitude threshold (e.g., >15 cm Hâ‚‚O) isn't required presence matters. Cough leakage is stress incontinence, not DO different mechanism. Voiding phase contractions are normal micturition, not overactivity. Filling-phase involuntariness distinguishes DO, key to its urodynamic definition, unlike size, stress, or voiding errors.

Correct Answer: A

Rationale: Post-PFUI continence is best addressed after restoring urethral continuity reconstruction (e.g., urethroplasty) precedes sphincter assessment. Contrast studies show anatomy, not function unpredictive. Bladder neck endoscopy evaluates structure, not continence limited. Partial injuries vary full distraction repairable. Continuity-first approach distinguishes it, key to stepwise PFUI management, unlike predictive or injury-type errors.