Biomedical subjects

G Blake Johnson

Publications and source records attributed to G Blake Johnson.

3 recordsLinked to original sources

PubMed2006

Advanced ureteroscopy: wireless and sheathless.

BACKGROUND: The introduction of a new generation of flexible ureteroscopes significantly advanced the therapeutic and diagnostic efficacy of the instrument, allowing greater access to all aspects of the upper urinary tract and facilitating wireless ureteroscopy. PATIENTS AND METHODS: Four hundred sixty consecutive upper urinary-tract procedures were performed utilizing the 7.5F actively deflectable, flexible ureteroscope. A prospective database of these procedures was maintained. The indications, access technique, complications, success rate of stone treatment, and access to lower-pole calices were evaluated. The accumulated clinical data were compared with a published database of 1000 consecutive flexible ureteroscopies. RESULTS: A stent was in place or had recently been in place in 108 of the procedures (24%). Of the remaining 352 flexible ureteroscopic procedures, only 11% (52) required any form of ureteral dilation to facilitate ureteral access. Two hundred twenty seven procedures were performed in which no guidewire was required to place the flexible endoscope in the upper urinary tract (i.e., "wireless" ureteroscopy). CONCLUSION: Wireless no-touch flexible ureteroscopy with the new flexible instruments is a feasible and safe technique for diagnostic and therapeutic procedures in most patients, irrespective of the location of the pathology, including the distal ureter. These ureteroscopes, with their exaggerated deflection, are ushering in a new era of endoscopic treatment of the upper urinary tract. Greater instrument deflectability and control can lead to shorter procedures and fewer treatment failures.

Equipment Design↗

PubMed2005

Ureteroscopic management of upper urinary tract transitional cell carcinoma.

PURPOSE OF REVIEW: Traditionally, nephroureterectomy has been the treatment of choice for transitional cell carcinoma of the upper urinary tract. In an effort to preserve renal function, conservative therapy has evolved from complex open surgery to minimally invasive ureteroscopic therapy. Considering the relatively recent emergence of ureteroscopic therapy, a review of technical considerations and treatment outcome is timely. RECENT FINDINGS: There is emerging evidence that ureteroscopic treatment of low grade upper tract lesions provides an acceptable oncologic result while preserving functioning renal parenchyma. In patients with low grade upper tract urothelial lesions, progression is rarely reported. Ureteroscopy has for over a decade been the premier diagnostic tool, with the actively deflectable flexible instrument being employed to map the entire intrarenal collecting system. Improvements in instrumentation and refinement in technique have broadened the application of the ureteroscope in treating upper urinary tract urothelial tumors. SUMMARY: For low grade lesions, which make up more than 50% of all presentations, ureteroscopic management has proven efficacious. As with similar grade lesions in the bladder, these patients require careful, consistent, and often lifelong follow up as many will develop recurrent lesions throughout the urothelium. Here too, ureteroscopy has a central role in surveillance.

Carcinoma, Transitional Cell↗

PubMed2003

Benign retroperitoneal schwannoma presenting as a giant adrenal tumor.

We report a 51-year-old man with a primary adrenal tumor presenting as a giant juxta-adrenal benign schwannoma. The patient was initially admitted for persistent fevers and underwent a sepsis workup. Abdominal ultrasound initially revealed an incidental right suprarenal mass, which measured 10 x 10 x 11 cm, estimated by computed tomography. Following a successful laparotomy, histologic examination confirmed that this giant tumor was a benign retroperitoneal schwannoma. Postoperatively, the patient remains disease-free, undergoing rehabilitation.

Adrenal Gland Neoplasms↗