Long-term outcome of retroperitoneoscopic partial versus total adrenalectomy in patients with Cushing's syndrome

BACKGROUND

We analyze the long-term outcome of surgery for Cushing's syndrome (CS) and the influence of the extent of surgical resection on the duration of postoperative cortisone substitution.

METHODS

One-hundred forty-one patients (129 female, 12 males; mean age: 45.7 ± 12.8 years) operated between January 2000 to June 2020 were included in the analysis. Patients suffered from manifest (124) or subclinical (17) CS due to benign unilateral adrenal neoplasia. All tumors were removed by the posterior retroperitoneoscopic approach. 105 patients had total (TA) and 36 partial (PA) adrenalectomies. All patients were discharged with ongoing corticosteroid supplementation therapy.

RESULTS

Follow-up data could be obtained for 83 patients. Twenty-four (1 male, 23 females; mean age 42.3 years) underwent PA and 59 TA (6 males, 53 females; mean age 44.6 years). Mean follow-up time was 107 ± 68 months (range: 6-243 months). The median duration of postoperative corticosteroid therapy was 9.5 months after PA and 11 months after TA (p = 0.1). Significantly, more patients after total adrenalectomy required corticosteroid therapy for more than 24 months (25% vs. 4%; p = 0.03). Recurrent ipsilateral disease occurred in one case after partial adrenalectomy and was treated by completion adrenalectomy. A case of contralateral recurrence associated with subclinical Cushing's syndrome was observed after total adrenalectomy.

CONCLUSIONS

The risk of local recurrence after partial adrenalectomy in CS is low. Cortical-sparing surgery may shorten corticosteroid supplementation therapy after surgery.

Imaging-based feedback cooling of a levitated nanoparticle

Imaging-based detection of the motion of levitated nanoparticles complements a widely used interferometric detection method, providing a precise and robust way to estimate the position of the particle. Here, we demonstrate a camera-based feedback cooling scheme for a charged nanoparticle levitated in a linear Paul trap. The nanoparticle levitated in vacuum was imaged using a complementary metal-oxide semiconductor (CMOS) camera system. The images were processed in real-time with a microcontroller integrated with a CMOS image sensor. The phase-delayed position signal was fed back to one of the trap electrodes, resulting in cooling by velocity damping. Our study provides a simple and versatile approach applicable for the control of low-frequency mechanical oscillators.

Super-resolution imaging of a low frequency levitated oscillator

We describe the measurement of the secular motion of a levitated nanoparticle in a Paul trap with a CMOS camera. This simple method enables us to reach signal-to-noise ratios as good as 10⁶ with a displacement sensitivity better than 10^-16 m²/Hz. This method can be used to extract trap parameters as well as the properties of the levitated particles. We demonstrate continuous monitoring of the particle dynamics on time scales of the order of weeks. We show that by using the improvement given by super-resolution imaging, a significant reduction in the noise floor can be attained, with an increase in the bandwidth of the force sensitivity. This approach represents a competitive alternative to standard optical detection for a range of low frequency oscillators where low optical powers are required.

Imaging Correlations in Heterodyne Spectra for Quantum Displacement Sensing

The extraordinary sensitivity of the output field of an optical cavity to small quantum-scale displacements has led to breakthroughs such as the first detection of gravitational waves and of the motions of quantum ground-state cooled mechanical oscillators. While heterodyne detection of the output optical field of an optomechanical system exhibits asymmetries which provide a key signature that the mechanical oscillator has attained the quantum regime, important quantum correlations are lost. In turn, homodyning can detect quantum squeezing in an optical quadrature but loses the important sideband asymmetries. Here we introduce and experimentally demonstrate a new technique, subjecting the autocorrelators of the output current to filter functions, which restores the lost heterodyne correlations (whether classical or quantum), drastically augmenting the useful information accessible. The filtering even adjusts for moderate errors in the locking phase of the local oscillator. Hence we demonstrate the single-shot measurement of hundreds of different field quadratures allowing the rapid imaging of detailed features from a simple heterodyne trace. We also obtain a spectrum of hybrid homodyne-heterodyne character, with motional sidebands of combined amplitudes comparable to homodyne. Although investigated here in a thermal regime, the method's robustness and generality represents a promising new approach to sensing of quantum-scale displacements.

Dynamical Two-Mode Squeezing of Thermal Fluctuations in a Cavity Optomechanical System

We report the experimental observation of two-mode squeezing in the oscillation quadratures of a thermal micro-oscillator. This effect is obtained by parametric modulation of the optical spring in a cavity optomechanical system. In addition to stationary variance measurements, we describe the dynamic behavior in the regime of pulsed parametric excitation, showing an enhanced squeezing effect surpassing the stationary 3 dB limit. While the present experiment is in the classical regime, our technique can be exploited to produce entangled, macroscopic quantum optomechanical modes.

Squeezing a thermal mechanical oscillator by stabilized parametric effect on the optical spring

We report the confinement of an optomechanical micro-oscillator in a squeezed thermal state, obtained by parametric modulation of the optical spring. We propose and implement an experimental scheme based on parametric feedback control of the oscillator, which stabilizes the amplified quadrature while leaving the orthogonal one unaffected. This technique allows us to surpass the -3  dB limit in the noise reduction, associated with parametric resonance, with a best experimental result of -7.4  dB. While the present experiment is in the classical regime, in a moderately cooled system our technique may allow squeezing of a macroscopic mechanical oscillator below the zero-point motion.

Nonoperative management of penetrating kidney injuries: a prospective audit

PURPOSE

The role of nonoperative management for penetrating kidney injuries is unknown. Therefore, we review the management and outcome of penetrating kidney injuries at a center with a high incidence of penetrating trauma.

MATERIALS AND METHODS

Data from all patients presenting with hematuria and/or kidney injury discovered on imaging or at surgery admitted to the trauma center at Groote Schuur Hospital in Cape Town, South Africa during a 19-month period (January 2007 to July 2008) were prospectively collected and reviewed. These data were analyzed for demographics, injury mechanism, perioperative management, nephrectomy rate and nonoperative success. Patients presenting with hematuria and with an acute abdomen underwent a single shot excretory urogram. Those presenting with hematuria without an indication for laparotomy underwent computerized tomography with contrast material.

RESULTS

A total of 92 patients presented with hematuria following penetrating abdominal trauma. There were 75 (80.4%) proven renal injuries. Of the patients 84 were men and the median age was 26 years (range 14 to 51). There were 50 stab wounds and 42 gunshot renal injuries. Imaging modalities included computerized tomography in 60 cases and single shot excretory urography in 18. There were 9 patients brought directly to the operating room without further imaging. A total of 47 patients with 49 proven renal injuries were treated nonoperatively. In this group 4 patients presented with delayed hematuria, of whom 1 had a normal angiogram and 3 underwent successful angioembolization of arteriovenous fistula (2) and false aneurysm (1). All nonoperatively managed renal injuries were successfully treated without surgery. There were 18 nephrectomies performed for uncontrollable bleeding (11), hilar injuries (2) and shattered kidney (3). Post-nephrectomy complications included 1 infected renal bed hematoma requiring percutaneous drainage. Of the injuries found at laparotomy 12 were not explored, 2 were drained and 5 were treated with renorrhaphy.

CONCLUSIONS

Penetrating trauma is associated with a high nephrectomy rate (24.3%). However, a high nonoperative success rate (100%) is achievable with minimal morbidity (9%).

Overview of a paediatric renal transplant programme

INTRODUCTION

Renal transplantation is the therapy of choice for children with end-stage renal failure. There are many challenges associated with a paediatric programme in a developing country where organs are limited.

METHODS

A retrospective review was undertaken of 149 paediatric renal transplants performed between 1968 and 2006 with specific emphasis on transplants performed in the last 10 years. Survival of patients and grafts was analysed and specific problems related to drugs and infections were reviewed.

RESULTS

On review of the total programme, 60% of the transplants have been performed in the last 10 years, with satisfactory overall patient and graft survival for the first 8 years post transplant. At this point, transfer to adult units with non-compliance becomes a significant problem. Rejection is less of a problem than previously but infection is now a bigger issue--specifically tuberculosis (TB), cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections with related complications. A wide variety of drugs are available for tailoring immunosuppression to minimise side-effects.

CONCLUSION

It is possible to have a successful paediatric transplant programme in a developing country. However, to improve long-term outcomes certain issues need to be addressed, including reduction of nephrotoxic drugs and cardiovascular risk factors and providing successful adolescent to adult unit transition.

High-dose ketoconazole therapy in prostatic cancer. A pilot study

There may be contraindications to oestrogen therapy for prostatic carcinoma, and also patient objections to orchidectomy as a form of therapy. Ketoconazole, a systemic antifungal drug, was evaluated in a dosage of 200 mg 8-hourly given orally as an alternative method of lowering serum testosterone levels. Nineteen patients were studied; 1 was withdrawn because of nausea and vomiting. Only 6 patients (33,3%) had serum testosterone levels in the castrate range after 7 days. It seems that higher doses may be needed to keep testosterone levels consistently low.

Fluid collections associated with renal allografts

In a series of 50 consecutive renal allograft patients, 4 developed lymphoceles and 1 developed a seroma which later became infected. In no instance could the fluid collection be held responsible for deterioration in graft function. Two of the lymphoceles occurred with ureteric strictures and perirenal abscess was associated with acute rejection. The significance of a perirenal collection with deteriorating renal function is discussed.

Kaposi's sarcoma of the penis

The 11th case of Kaposi's sarcoma of the glans penis is reported. Aetiology and treatment are discussed and evidence adduced to support a conservative surgical approach by local excision, supplemented if necessary by low dosage irradiation and possibly methotrexate infusion.