Dorsal Anastomosis Research Articles

Non-transecting dorsal mucosal anastomosis plus ventral oral graft for the treatment of urethral bulbar strictures: single surgeon experience.

To report our experience with the non-transecting dorsal mucosal anastomosis plus ventral oral graft urethroplasty (NTAVOG) for the repair of tight bulbar urethral strictures. Data of 68 men with tight bulbar strictures underwent NTAVOG urethroplasty between 2012 and 2019 were retrospectively revised. The urethra was opened ventrally; the dorsal scarred mucosa was excised preserving the spongiosum; the mobilized mucosal edges were anastomosed to recreate the dorsal urethral plate; the repaired urethral plate was augmented by the ventral oral graft and the spongiosum was closed over it. Successful urethral reconstruction was defined as normal voiding without the need for any postoperative procedure. Sexual function was investigated using a validated questionnaire. Median follow-up was 58months (IQR 38-63) and mean stricture length was 1cm (IQR 1-1.5). Of 68 cases, 56 (82.4%) were successful and 12 (17.6%) were failures requiring re-treatment. At multivariable analysis, no preoperative factor was significantly associated with recurrence. None of the preoperatively sexually active 53 patients reported postoperative erectile impairment and all were satisfied with their sexual life. The main limitation is the retrospective design. In cases of tight bulbar stricture, the NTAVOG urethroplasty provides adequate urethral augmentation by preserving the spongiosum and avoiding postoperative sexual complications. We presented a series of patients undergone non-transecting dorsal anastomosis plus ventral oral graft urethroplasty for tight bulbar stricture. This treatment seems to be safe and with limited postoperative complications thanks to the preservation of the corpus spongiosum.

Anatomical features of the canine C2-C3 spinal cord vascular environment

Interarcuate branch (IAB) is a vascular structure, particularly developed in C2-3 intervertebral space, forming a dorsal bridge that connects ventral venous plexi in the vertebral canal. While precisely described in the human, the precise anatomical features of IABs have not been reported in the veterinary literature. The purpose of this study is to describe the features and relations of IABs in the C2-3 vertebral canal. 10 dogs were enrolled; 5 dogs for necropsy and 5 dogs for histology. The ventral venous plexi in the cervical spine of 5 dogs were injected with latex and underwent vertebral canal dissection for visual assessment of the IAB. Two out of 5 dogs were injected with the addition of barium sulfate and underwent a CT scan. The C2-3 regions of 5 small-breed dogs were harvested for histological examinations. IABs arose from the ventral venous plexus at the level of the intervertebral vein; they originated from 2 separate branches located caudally and cranially to the intervertebral foramen, forming a ventrodorsal triangle surrounding the spinal nerve root. No dorsal anastomosis was observed on the CT scan nor at dissection but were observed histologically. A cervical fibrous sheath was observed all around the vertebral canal. IABs are voluminous venous structures at the C2-3 intervertebral space in dogs and found within a split of the cervical fibrous sheath, which is adherent to the interarcuate ligament and the ligamentum flavum. This anatomical description is paramount when planning an approach to the C2-3 intervertebral space.

New Reconstructive Surgery for Penile Paraffinoma to Prevent Necrosis of Ventral Penile Skin

To introduce a new repair technique, inverted V-shape, for penile paraffinoma without necrosis of the ventral skin anastomosed. From March 2006 to July 2012, 34 patients underwent penile paraffinoma repair using the T-style or a new operation procedure, the inverted V-shape anastomosis with a bilateral scrotal flap. The patients were subdivided into 2 groups. In group 1, each patient underwent the T-style anastomosis. In group 2, each patient underwent the inverted V-shape anastomosis. Two circumferential incisions were made, one at the skin just proximal to the corona of the penis and one at the penoscrotal junction. Complete removal of the involved skin and subcutaneous tissue, including paraffinoma, was performed. Both scrotal flaps were drawn to the mid-dorsal portion of the corona after scrotal flaps were incised appropriately and sutured with a T-style anastomosis between the coronal and scrotal flaps. The ventral skin was anastomosed end to end to avoid the T-style anastomosis, similar to a dorsal anastomosis. We created an inverted V incision 1 cm below from the anastomosis site. The scrotal flaps were sutured layer by layer. All 14 flaps survived completely without the necrosis of the ventral skin. The results were successful and without any major complications. Penile resurfacing without the T-style anastomosis at the ventral corona with bilateral scrotal flaps is a new technique for repair of penile paraffinoma. It is an effective and reliable method, especially for the saving corona and scrotal flap anastomosed to the ventral penile body.

Spatial relations of dorsal anastomoses and lesion border after middle cerebral artery occlusion.

Occlusion of the middle cerebral artery invariably results in infarction of tissue in stroke-prone spontaneously hypertensive rats (SHRSP). To determine if the lesion border extends beyond the territory of the occluded middle cerebral artery or if the lesion enlarges with time after the occlusion, spatial relations of the lesion and the primary anastomosing collateral branches were investigated. Measurements were made 1 day (n = 8) or 21 days (n = 8) after occlusion in 5-8-week-old SHRSP brains marked by triphenyltetrazolium chloride (TTC) or tissue atrophy. After 1 day of occlusion, the border between TTC-marked and -unmarked tissue was parallel to, and without spatial displacement from, the medial border of infarcted tissue measured 21 days after the occlusion. Thus, the TTC border accurately localizes the medial border of ischemic tissue that progresses to atrophy. The lesion border was 1.16 +/- 0.04 mm downstream from the anastomoses, and the mean distance was not significantly different in frontal, parietal, or rostral occipital regions or between the 2 groups of rats. Thus, a small but significant amount of tissue between the anastomoses and the lesion border was protected against infarction after middle cerebral artery occlusion in SHRSP. After 21 days of occlusion, the dorsal anastomoses were enlarged, bilaterally symmetric in position but not size, and without displacement from the anastomoses in 1-Day rats. Large-diameter anastomoses were further from the lesion than small-diameter anastomoses in both groups of rats, thus indicating that protection is greater near large anastomoses than near small ones.(ABSTRACT TRUNCATED AT 250 WORDS)

Tracheal patterns in larval Chironomidae (Diptera, Nematocera)

AbstractThe tracheal systems of 142 chironomid larvae (42 species) were examined. These tracheal patterns showed considerable variation, both between subfamilies, and within a particular subfamily. The dorsal trunks, lateral trunks, dorsal anastomoses, and subcuticular tracheation were the major tracheal components examined in this study. Orthocladiinae, Diamesinae and Tanypodinae larvae exhibit the most extensive tracheal systems differing mainly in the placement of anastomoses. In some Podonominae species the tracheal system extends only to abdominal segment 8, where the trunks merge to form an open spiracle. Other podonomines, though not examined, are apneustic. The Chironominae tracheal system appears to extend the entire length of the larva, but only certain portions of it are filled with air. In Tanytarisini air is present in the thoracic tracheae and the terminal abdominal tracheae. In some Chironomini, air is present only in the thoracic tracheae, while other members of this tribe exhibit the 'Tanytarsini' pattern. The phylogeny of the Chironomidae, and the effects of environmental factors on the tracheal system are discussed.

THE TRACHEAL SYSTEM OF THE LARVAE OF HYPODERMA (DIPTERA: OESTRIDAE) LINEATUM AND H. BOVIS

AbstractThe tracheal system of all three larval instars of Hypoderma is metapneustic. The arrangement generally resembles that in the Cyclorrhapha except for reduction of the dorsal anastomoses, lateral, longitudinal, and spiracular tracheae and the apparent absence of ventral cervical tracheae. The transverse connectives consist mainly of secondary and tertiary branches, but the dorsal anastomoses have only secondary branches, if any. The transverse connectives extend to the ventral and lateral somatic musculature and to the alimentary canal. The dorsal anastomoses supply mainly the heart and dorsal somatic musculature.