Primary outcome

To provide a comprehensive comparison regarding the use of high magnification in hypospadias vs. optical magnification.

Secondary outcome parameters

1- To introduce the new high magnification technique in the armamentarium of hypospadias surgery.

2- To build a prospective randomized controlled study to evaluate the outcome of high magnification in hypospadias surgery.

Study participants

Fifty-two patients enrolled in our study were divided into two groups:

Group A (26)

High magnification was used (VITOM Karl Storz Endoscopy GmbH, Tuttlingen, Germany or Surgical microscope, Carl Zeiss Microscopy GmbH), along with microsurgical instruments. Vicryl 8-0 suture was used for the urethroplasty.

Group B (26)

Patients were operated upon by conventional instruments (fine tip but not microsurgical instruments), sutures, and magnification (× 3.5). Vicryl 6-0 suture was used for the urethroplasty, with loupes assisted magnification‖.

Inclusion criteria:

1.

Patients with distal hypospadias (down to mid-penile shaft)

2.

Patients with mild to moderate chordee (up to 30°).

3.

Patient’s age is between 6 months and 2 years.

Exclusion criteria:

1.

Cases previously operated upon (recurrent, circumcised, or crippled).

2.

Cases with proximal hypospadias (proximal penile, peno-scrotal, or scrotal).

3.

Patients with severe chordee (more than 30°), if more than 30° by erection test patient is excluded from the study.

4.

Associated anomalies or syndromes.

Sample size

The proposed sample size for our study is 52 hypospadias cases divided into two groups.

The justification for the sample size:

Tests-means: difference between two independent means (two groups).

Analysis: a priori: compute required sample size

Input:

Tail(s)=One

Effect size d=0.7

α err prob=0.05

Power (1-β err prob)=0.8

Allocation ratio N2/N1=1

Output:

Non-centrality parameter δ=2.5238859

Critical t=1.6759050

Df=50

Sample size group 1=26

Sample size group 2=26

Study location

This study was conducted in the pediatric surgery department at Abou El-Reesh Specialized Pediatric Hospital, Kasr Alainy, Faculty of Medicine, Cairo University.

Study timing

From 1st of July 2020 to 1st of July 2021.

Operative details

All patients were positioned in the frog-leg supine position at the foot of the table. After induction with anesthesia but prior to draping, the surgeon’s position and adjusting the focus of the microscope/VITOM is done, and then swing it away from the field. All patients were subjected to general anesthesia augmented with a caudal block (with infiltration with 1:100,000 xylocaine and adrenaline solution) for extended post-operative pain relief. We obtained written informed consent to take medical photography as a routine in our practice. The penis is photographed in antero-posterior and lateral views after the drapes application. We used 2 swabs to retract the foreskin, remove the smegma, and povidone-iodine is applied. A vicryl 6-0 suture is passed on the dorsal surface of the glans in a vertical manner for retraction. In some cases, a tourniquet was applied from the start of the operation, in the second case tourniquet was applied just before the urethroplasty, and in other cases, no tourniquet was used at all. Using the tourniquet and its timing was attributed to the surgeon’s preference. The tourniquet time is monitored precisely and not used for more than 25 minutes.

According to the surgeon’s preference, the high magnification (VITOM or Microscope) could be used throughout the whole procedure, or it may be confined to the urethroplasty.

Surgical microscope

The microscope used is a double foot switch one for the focus and the other for controlling the zoom, with a second head for the assistant. Working distance of 200–415 mm, large visual field with widefield eyepieces (× 12.5 or × 10). The initial parts of the operation including diagramming of the repair, degloving, release of the chordee, and mobilization of tissues are done without high magnification in most of the patients and the high magnification (× 6–24 magnification) either VITOM or Microscope is used mainly during urethroplasty.

Video telescopic operating microscope (VITOM, Exoscope)

VITOM, (Karl Storz Endoscopy GmbH, Tutlingen, Germany) was used and it served To accurately identify and define delicate anatomic structures by providing images of superb quality, (× 8–30) magnification zoom, and good illumination. During the procedures, surgeons could view the high-definition (HD) VITOM images displayed on a 26-in. flat screen at a comfortable viewing distance and angle. The use of 3D glasses allowed better visualization of the anatomical and operative details and helped the non-scrubbed colleagues to better visualize the operation and to precisely observe the operative steps.

At the end of each operation, the surgeon and the assistant were asked about the image quality, comfort with the VITOM set-up, neck strain, and fatigue during the operation.

Also, the attending non-scrubbed colleagues were asked about the image quality and the potential teaching value of the VITOM magnification.

Post-operative care

Follow-up visits are scheduled at approximately 2 weeks thereafter. The dressing was removed after the first two postoperative days and the catheter was removed at 7th to 10th days postoperatively.

Complications were classified as early complications, e.g., urethrocutaneous fistula, postoperative bleeding, edema, dehiscence, infection, and retention, and late complications, e.g., meatal stenosis, urethral stricture, and recurrence.