Biomedical subjects

Zihai Ding

Publications and source records attributed to Zihai Ding.

4 recordsLinked to original sources

PubMed2006

[Applied anatomy study and clinical application of great saphenous veno-saphenous neurocutaneous vascular flap].

OBJECTIVE: To provide the anatomic basis for defect repair of the knee, leg, foot and ankle with great saphenous veno-saphenous neurocutaneous vascular island flaps. METHODS: The origin, diameter, branches, distribution and anastomoses of the saphenous artery and saphenous neurocutaneous vascular were observed on 20 sides of adult leg specimens and 4 fresh cadaver voluntary legs. Another 4 fresh cadaver voluntary legs were radiographed with a soft X-ray system after the intravenous injection of Vermilion and cross-sections under profound fascial, other hand, micro-anatomic examination was also performed in these 4 fresh cadaver legs. The soft tissue defects in lower extremity, upper extremity, heel or Hucou in hand were repaired with the proximal or distal pedicle flaps or free flaps in 18 patients (12 males and 6 females,aging from 7 to 53 years). The defect was caused by trauma, tumour, ulcer and scar. The locations were Hucou (1 case), upper leg (3 cases), lower extremity and heal (14 cases). Of then, 7 cases were complicated by bone exposure, 3 cases by tendon exposure and 1 case by steel espouse, the defect size were 4 cm x 4 cm to 7 cm x 13 cm. The flap sizes were 4 cm x 6 cm to 8 cm x 15 cm, which pedicle length was 8-11 cm with 2.5-4.0 cm fascia and 1-2 cm skin at width. RESULTS: Genus descending genicular artery began from 9.33 +/- 0.81 cm away from upper the condyles medialis, it branched saphenous artery accompanying saphenous nerve descendent. And saphenous artery reached the surface of the skin 7.21 +/- 0.82 cm away from lower the condyles medialis, and anastomosed with the branches of tibialis posterior artery, like "Y" or "T" pattern. The chain linking system of arteries were found accompanying along the great saphenous vein as saphenous nerve, and then a axis blood vessel was formed. The small artery of only 0.05-0.10 mm in diameter, distributed around the great saphenous vein within 5-8 mm and arranged parallelly along the vein like water wave in soft X-ray film. All proximal flaps, distal pedicle flaps and free flaps survived well. The appearance, sensation and function were satisfactory in 14 patients after a follow-up of 6-12 months. CONCLUSION: The great saphenous vein as well as saphenous neurocutaneous has a chain linking system vascular net. A flap with the vascular net can be transplanted by free, by reversed pedicle, or by direct pedicle to repair the wound of upper leg and foot. A superficial vein-superficial neurocutaneous vascular flap with abundance blood supply and without sacrificing a main artery is a favourite method in repair of soft tissue defects in foot and lower extremity.

Adolescent↗

PubMed2004

[Experimental study of posterior pedicle screw placement on atlas].

OBJECTIVE: To assess the possibility of placing the posterior pedicle screw on atlas. METHODS: Twenty human cadaver specimens were used to insert pedicle screws in atlas, through the posterior arch or the pedicle of C1 into the lateral mass. The screw entry point was on the posterior surface of C1 posterior arch and at the intersection of the vertical line through the center of C2 inferior articular process and the horizontal line at least 3 mm below the superior rim of the C1 lamina. The screw of 3.5 mm in diameter was placed in a direction of 10 degrees medial angle and 5 dgrees upward angle. After placement of C1 pedicle screw, the distance from C1 screw entry point to the medial-lateral midpoint of C1 pedicle, the maximum length of screw trajectory and the actual screw trajectory angles were measured. The direction of screw penetrating through the cortical of C1 pedicle or lateral mass and the injuries to the vertebral artery and spinal cord were observed. RESULTS: Forty pedicle screws were placed on atlas, the mean distance from C1 screw entry point to the medial-lateral midpoint of C1 pedicle was (2.20 +/- 0.42)mm, the maximum length of screw trajectory averaged (30.51 +/- 1.59)mm, and the actual screw trajectory angle measured (9.7 +/- 0.67)degrees in a medial direction and (4.6 +/- 0.59)degrees in a upward direction. Only 1 screw penetrated the upper cortical bone of the atlas pedicle because the upward angle was too large, and 8 screws were inserted so deep that the inferior cortical bone of the C1 lateral mass was penetrated. But no injuries to the vertebral artery and spinal cord were observed. CONCLUSION: C1 posterior pedicle screw fixation is quite accessible and safe, but the surgeons should pay attention to the angle and the depth of the screw placement.

Adult↗

PubMed2002

[Microanatomy study on sinus triangle region].

OBJECTIVES: To explore shape and position relationship of the structures with in sinus triangle region, and provide the anatomic foundation for extended presigmoid operative approach. METHODS: Ten cadaveric heads and 15 skull-base specimens fixed with 10% formalin, with aid of operative microscope, the shape and relations of structures with in the sinus triangle region were observed and microphotographed. Four cadaveric heads were sectioned in different plane using collodion embedding process. RESULTS: Jugular blub (JB) had high -placed jugular blub (HJB), normal jugular blub (NJB) and low-placed jugular blub (LJB). The incidence of HJB was 8% and 18% for the left and right sides (P < 0.01). The JB dome can extend upward the hypotympanic cavity and the posterior wall of the internal acoustic meatus. The incidence of NJB and LJB was 36% and 30%, and 6% and 2% respectively. The level distance between the posterior semicircular canal and petrosal posterior surface was (4.1 +/- 1.1) mm. The distance between the JB and vertical part of the facial nerve was (3.2 +/- 0.5) mm and (2.0 +/- 0.4) mm. The distance between the JB and posterior margin of the internal acoustic port was (7.5 +/- 1.7) mm and (4.0 +/- 1.0) mm. CONCLUSIONS: Knowing the shape and position relationship of structures in the sinus triangle region is favorable for preserving the important structures in extended presigmoid operative approach.

Autopsy↗

PubMed2002

[Microsurgical anatomy of craniocervical junction region].

OBJECTIVES: To study the shape and the structures in the craniocervical junction region (CCJR) and the safety of far lateral approach. METHODS: Ten cadaveric heads and 20 skull-base specimens were fixed with 10% formalin, and 4 of the 10 cadaveric heads were sectioned in different plane with the aid of operative microscope. The shape and relation of structures in the CCJR were observed. RESULTS: The third segment of the vertebral artery(VA) was 21.6(15.3 31.9) mm. An incomplete bony canal was found to be 15% and complete bony canal surrounding the VA to be 5% on the VA groove. The distance of the left and right VA was 14.3a(c)(9.8 15.2) mm on the entry into the dura. The length of the occipital condyle was 26.8(25.1 28.2) mm, with the thickness of its anterior, middle and posterior one-third part was 9.9(9.6 10.6) mm, 11.2(9.2 13.1) mm and 8.6 (8.3 9.0) mm respectively. The distance between the posterior pole of the occipital condyle and the intracranial orifice of the hypoglossal canal was 9.9(8.6 11.4) mm, and between the posterior pole and the extracranial orifice was 16.1(13.5 17.1) mm. The transverse process of the atlas was the most important bony landmark for the approach. CONCLUSIONS: Knowing the shape and relationship of the VA and occipital condyle in the CCJR is helpful in preserving the important structures in far lateral approach to target region.

Humans↗