Proposition for new terminologies in PCNL: what does ‘ultra-mini-micro’ actually mean?

Ever smaller miniaturised techniques are being developed for percutaneous nephrolithotomy (PCNL), with access sheaths now as small as 4.8Fr being used in adults. With the ever expanding use of the terms “micro” “mini” or “ultra” techniques, the terminology can be somewhat confusing. We propose a simple classification system to standardise the terminology for PCNL, encapsulating technological and procedural advancements.     

Pyogenic Liver Abscess Following Pancreaticoduodenectomy: Risk Factors,Treatment, and Long-Term Outcome

Background

Pancreaticoduodenectomy (PD) remains a challenging operation with a 40 % postoperative complication rate. Pyogenic liver abscess (PLA) is an uncommon complication following PD with little information on its incidence or treatment. This study was done to examine the incidence, risk factors, treatment, and long-term outcome of PLA after PD.

Methods

We retrospectively reviewed 1,189 patients undergoing PD (N?=?839) or distal pancreatectomy (DP) (N?=?350) at a single institution over a 14-year period (January 1, 1994–January 1, 2008). Pancreatic databases (PD and DP) were queried for postoperative complications and cross-checked through a hospital-wide database using ICD-9 codes 572.0 (PLA) and 006.3 (amebic liver abscess) as primary or secondary diagnoses. No PLA occurred following DP. Twenty-two patients (2.6 %) developed PLA following PD. These 22 patients were matched (1:3) for age, gender, year of operation, and indication for surgery with 66 patients without PLA following PD.

Results

PLA occurred in 2.6 % (22/839) of patients following PD, with 13 patients (59.1 %) having a solitary abscess and 9 (40.9 %) multiple abscesses. Treatment involved antibiotics and percutaneous drainage (N?=?15, 68.2 %) or antibiotics alone (N?=?7, 31.8 %) with a mean hospital stay of 12 days. No patient required surgical drainage, two abscesses recurred, and all subsequently resolved. Three patients (14 %) died related to PLA. Postoperatively, patients with biliary fistula (13.6 vs. 0 %, p?=?0.014) or who required reoperation (18.2 vs. 1.5 %, p?=?0.013) had a significantly higher rate of PLA than matched controls. Long-term follow-up showed equivalent 1-year (79 vs.74 %), 2-year (50 vs. 57 %), and 3-year (38 vs. 33 %) survival rates and hepatic function between patients with PLA and matched controls.

Conclusions

Postoperative biliary fistula and need for reoperation are risk factors for PLA following PD. Antibiotics and selective percutaneous drainage was effective in 86 % of patients with no adverse effects on long-term hepatic function or survival.     

Optimum Projection Angle for Attaining Maximum Distance in a Rugby Place Kick

This study investigated the effect of projection angle on the distance attained in a rugby place kick. A male rugby player performed 49 maximum-effort kicks using projection angles of between 20 and 50°. The kicks were recorded by a video camera at 50 Hz and a 2 D biomechanical analysis was conducted to obtain measures of the projection velocity and projection angle of the ball. The player’s optimum projection angle was calculated by substituting a mathematical expression for the relationship between projection velocity and projection angle into the equations for the aerodynamic flight of a rugby ball. We found that the player’s calculated optimum projection angle (30.6°, 95% confidence limits ± 1.9°) was in close agreement with his preferred projection angle (mean value 30.8°, 95% confidence limits ± 2.1°). The player’s calculated optimum projection angle was also similar to projection angles previously reported for skilled rugby players. The optimum projection angle in a rugby place kick is considerably less than 45° because the projection velocity that a player can produce decreases substantially as projection angle is increased. Aerodynamic forces and the requirement to clear the crossbar have little effect on the optimum projection angle.

Key Points

• The optimum projection angle in a rugby place kick is about 30°.
• The optimum projection angle is considerably less than 45° because the projection velocity that a player can produce decreases substantially as projection angle is increased.
• Aerodynamic forces and the requirement to clear the crossbar have little effect on the optimum projection angle.

Key Words: Biomechanics, kinematics, projectile     

Can we improve the definition of high‐risk,hormone naïve,non‐metastatic prostate cancer?

• To identify criteria beyond Tumour‐Node‐Metastasis (TMN)‐, prostate‐specific antigen (PSA)‐ and Gleason score‐based standard classifications to enhance the stratification of non‐metastatic high‐risk prostate cancer.
• A detailed search of the literature was performed using PubMed.
• The authors reviewed the literature and used a modified Delphi approach to identify relevant approaches to enhance standard classifications.
• Specific criteria for high‐risk prostate cancer vary across guidelines and clinical trials, reflecting the differing perspectives concerning the definition of ‘risk’ between different specialities within the urology/radiation oncology community.
• In addition to the present classifications, evidence exists that the measure of cancer volume can provide additional prognostic value.
• More accurate imaging, especially multiparametric magnetic resonance imaging can also provide information concerning staging and cancer volume, and thus may assist in the identification of patients with high‐risk prostate cancer.
• A refined definition of non‐metastatic high‐risk prostate cancer is proposed.
• Within this high‐risk cohort, patients with multiple high‐risk criteria are especially at risk of prostate cancer‐specific mortality.

     

Impact of Chemoradiotherapy on CSF Leak Repair after Skull Base Surgery

Background Transnasal endoscopic resection (TER) has become the treatment of choice for many skull base tumors. A major limitation of TER is the management of large dural defects and the need for repair of cerebrospinal fluid (CSF) leaks, particularly among patients who are treated with chemotherapy (CTX) or radiotherapy (RT). The objective of this study is to determine the impact of CTX and RT on the success of CSF leak repair after TER. Methods We performed a retrospective chart review of a single-institution experience of TER from 1992 to 2011. Results We identified 28 patients who had endoscopic CSF leak repair after resection of malignant skull base tumors. Preoperative RT was utilized in 18 patients, and 9 had undergone CTX. All patients required CSF leak repair with rotational flaps after cribriform and/or dural resection. CSF leak repair failed in three patients (11%). A history of RT or CTX was not associated with failed CSF leak repair. Conclusion Adjuvant or neoadjuvant CTX or RT is not associated with failed CSF leak repair. Successful CSF leak repair can be performed in patients with malignant skull base tumors with an acceptable risk profile.