[Effects of bilobated superficial peroneal artery perforator flap in repairing two adjacent wounds of the fingers].

Objective: To investigate the therapeutic efficacy of bilobated superficial peroneal artery perforator flap in repairing two adjacent wounds of the fingers. Methods: A retrospective observational study was conducted. From January 2021 to January 2022, 15 patients with two adjacent wounds of the fingers who met the inclusion criteria were hospitalized in Suzhou Ruihua Orthopaedic Hospital, including 10 males and 5 females, aged 25 to 51 years. The area of single wound after debridement was from 2.5 cm×2.0 cm to 7.5 cm×2.5 cm. All the wounds were repaired by the bilobated superficial peroneal artery perforator flap from the lower leg. The single lobe area of bilobated flap was from 3.0 cm×2.0 cm to 8.0 cm×3.0 cm. The wounds in all the donor sites were sutured directly. During the operation, the number of resected flaps, the number and type of carried perforators were recorded, and the calibers of perforator and superficial peroneal artery and the length of vascular pedicle were measured. The survival of flap and the wound healing in the donor and recipient sites were recorded after operation. The recovery of donor and recipient sites were recorded during follow-up. At the last follow-up, the repair effect of flap was evaluated by the comprehensive evaluation scale, and the sensory function of flap was evaluated by the sensory function evaluation standard of British Medical Research Association. Results: During the operation, 15 bilobated flaps were successfully resected, carrying 36 superficial peroneal artery perforators, all of which were septocutaneous perforators with the caliber of 0.2-0.8 mm. The caliber of superficial peroneal artery was 0.4-1.1 mm and the length of vascular pedicle was 3-8 cm. After operation, all the flaps survived with no vascular crisis occurred, and the wounds in donor and recipient sites healed well. During the follow-up of 6 to 12 months, the color and texture of flaps were similar to those of normal tissue in the hand and the appearance of flap was good in 10 cases; the other 5 cases underwent the stage Ⅱ flap thinning and plastic surgery 6 months after operation due to the bloated appearance of flaps. There was only linear scar in the donor site of lower leg, with no obvious scar hyperplasia or pigmentation, and there was no obvious adverse effect on the sensation or motor function of the distal limbs in the donor area. At the last follow-up, the repair effect of flap of 15 patients was excellent in 11 cases and good in 4 cases, and the sensory function of the flap was evaluated as grade S2 in all cases. Conclusions: The bilobated superficial peroneal artery perforator flap has high proportion of septocutaneous perforator, and the blood supply is sufficient and reliable. Using this flap to repair two adjacent wounds of the fingers causes minimal damage to the donor area, only one group of blood vessels is needed to be anastomosed to repair two wounds, the difficulty of microoperation is reduced, and good flap repair effect and sensory function can be obtained.

[Curative effects of the superficial peroneal artery perforator flap carrying multiple perforators in repairing hand and foot wounds].

Objective: To investigate the curative effects of the superficial peroneal artery perforator flap carrying two and more homologous perforators in repairing hand and foot wounds. Methods: A retrospective observational study was conducted. From January to September 2021, 23 patients with hand and foot wounds combined with bone or tendon exposure who met the inclusion criteria were admitted to Suzhou Ruihua Orthopaedic Hospital, including 16 males and 7 females, aged 23 to 68 years. After expansion of the wound, the wound area was 3.0 cm×2.0 cm to 11.0 cm×4.0 cm. All the wounds were repaired with the superficial peroneal artery perforator flap carrying two and more homologous perforators. The area of the resected flap was 4.0 cm×2.0 cm to 12.0 cm×5.0 cm. All the wounds in donor areas were sutured directly. During the operation, the resection of the flap, the number and caliber of carried perforators, the caliber of superficial peroneal artery, the length of vascular pedicle, and the number of accompanying veins of the superficial peroneal artery were recorded. The survival of the flap, the occurrence of complications, and the wound healing in the donor area were observed after operation. The recovery of the donor and recipient areas was followed up. At the last follow-up, the comprehensive evaluation scale was used to evaluate the curative effect of flap repair, and the sensory grading scale was used to evaluate the sensory function of the recipient area. Results: Totally 24 flaps were successfully resected in surgical operations, carrying 56 superficial peroneal artery perforators in total, with the caliber of perforators of 0.20-0.70 mm. The calibers of all perforators carried by 7 flaps were smaller than 0.40 mm. Nineteen flaps carried 2 perforators each, 3 flaps carried 3 perforators each, 1 flap carried 4 perforators, and 1 flap carried 5 perforators. During the operation, the superficial peroneal artery was resected with a caliber of 0.40-1.50 mm, the vascular pedicle was 2-6 cm in length, and each superficial peroneal artery had two accompanying veins. After operation, all the flaps survived smoothly, no vascular crisis or distal necrosis occurred, and the wounds healed well in the donor area. During the follow-up of 6 to 10 months after operation, the color, texture, and elasticity of the recipient area were good. Among them, 6 recipient areas were thinned and reshaped because of bloating. There was only linear scar and no obvious scar hyperplasia or pigmentation in the donor area, without significant change in sensory or motor function. At the last follow-up, the curative effect evaluation of flap repair was excellent in 22 flaps and good in 2 flaps, and the sensory function evaluation of the recipient area was grade S3 in 1 area and grade S2 in 23 areas. Conclusions: The superficial peroneal artery perforator flap with two and more homologous perforators has sufficient and reliable blood supply and is effective in repairing hand and foot wounds. It provides an ideal solution for the clinical problem in which the original operation scheme is abandoned due to the existence of only multiple slender perforators of caliber smaller than 0.40 mm, and only a single perforator in the operative field that cannot satisfy the needs of the flap blood supply and recipient area.

[Morphological study on the transverse branch of lateral femoral circumflex artery based on digital subtraction angiography].

Objective: To summarize the morphological characteristics of the transverse branch of lateral femoral circumflex artery (LFCA) using digital subtraction angiography (DSA) and explore its clinical significance. Methods: A retrospective observational study was conducted. From October 2020 to May 2021, 62 patients with soft tissue injuries in the extremities were hospitalized in Suzhou Ruihua Orthopedic Hospital, including 40 males and 22 females, aged from 20 to 72 years. DSA was performed in the lateral femoral region of patients before the anterolateral thigh flap transplantation, and in combination with imaging scale to observe and measure the general condition of the blood vessels and the occurrence (with the occurrence rate being calculated), source artery, location of the origin point, direction of course, and the location of the perforating point of the cutaneous perforator of the transverse branch of LFCA, and in addition to classify the morphological characteristics of the transverse branch. Results: DSA detection showed that the femoral artery, the deep femoral artery, and the branches of LFCA were clearly distinguishable in 62 patients. Transverse branches of LFCA were observed in 59 patients, including 52 cases with a single transverse branch, and 7 cases with double transverse branches. The occurrence rate of transverse branches was 95.2% (59/62). A total of 66 transverse branches of LFCA were observed, of which 3 originated from the deep femoral artery, and 63 originated from the LFCA. The origin point of the transverse branch was 6.5-12.7 cm away from the anterior superior iliac spine. The transverse branch which was approximately perpendicular to the long axis of the body, originated outwards, ran between the ascending branch of LFCA and the oblique branch of LFCA, and branched along the way, with the trunk running under the greater trochanter. The perforating point of the cutaneous perforator of the transverse branch was 8.0-18.0 cm away from the anterior superior iliac spine. In the classification of morphological characteristics of the transverse branch of LFCA, the most common type was the one that originated from the same trunk with other branches of LFCA, accounting for 50.0% (31/62), followed by the one that originated from the singular trunk of LFCA (12 cases) or deep femoral artery (3 cases), accounting for 24.2% (15/62); the special type accounted for 21.0% (13/62), including 7 cases of double transverse branches and 6 cases of the transverse branch originated from the same trunk with multiple other branches of LFCA; those with small/absent transverse branch only accounted for 4.8% (3/62). Among the above-mentioned common trunk relationship of two branches, those with shared trunk of ascending and transverse branches were most frequently observed, accounting for 77.4% (24/31); those with shared trunks of the transverse and oblique branches (5 cases) and the transverse and descending branches (2 cases) accounted for 22.6% (7/31) altogether. Conclusions: A high incidence rate of the transverse branch of LFCA is observed through DSA. The transverse branch originates from the lateral femoral artery approximately perpendicular to the long axis of the body, mainly from the same trunk with another main branch of LFCA, especially the ascending branch. This positioning analysis can provide an important reference for the design and resection of anterolateral femoral flaps.

[Clinical effects of anterolateral thigh flap with blood supply source of medial femoral perforator in repairing the wounds on extremities].

Objective: To investigate clinical effects of anterolateral thigh flap with blood supply source of medial femoral perforator in repairing the wounds on extremities. Methods: A retrospective observational study was conducted. From October 2018 to June 2021, Suzhou Ruihua Orthopedic Hospital admitted 12 patients (11 males and 1 female, aged 24-64 years) who met the inclusion criteria, and did not have the lateral circumflex femoral artery during anterolateral thigh flap resection, or changed to medial femoral perforator as a source of blood supply due to small perforator to repair the wound with flap transplantation. The wounds were on the upper limbs in 7 cases and on the lower limbs in 5 cases. The wound area after debridement was 8.0 cm×5.0 cm-24.0 cm×6.5 cm, and the applied flap area was 9 cm×6 cm-25 cm×7 cm. During transplantation, the perforating branch or source artery of the flap was anastomosed end to end with the vascular pedicle of the recipient area. Subcutaneous beauty suture was performed on all the donor wounds. After operation, the survival of the flap and vascular crisis were observed; and the wound healing at the donor site was observed. During follow-up, the texture of the flap and complications at the donor site were observed. At the last follow-up, the effect of flap repair was evaluated by using the modified self-made comprehensive efficacy rating table. Results: After operation, all the flaps of patients survived without vascular crisis; the wounds in the donor site healed smoothly. During follow-up of 6 to 26 months, the flaps had good texture; only linear scars remained in the donor area without scar contracture, pain or other discomfort. At the last follow-up, the total score of flap repair effect of 12 patients was 75-95, with an average of 87, of which 5 cases were rated as excellent, 6 cases as good, and 1 case as fair, and the proportion of excellent and good patients was 11/12. Conclusions: The application of anterolateral thigh flap with blood supply from the medial femoral perforator to repair wounds on extremities is an alternative method for the vascular variations such as no descending branch, oblique branch, or small perforator of the lateral circumflex femoral artery during the resection of the anterolateral thigh flap. This operation has the advantages of simple operation, small trauma, and others, which effectively ensures the smooth operation.

[Anatomical characteristics and clinical application of anterolateral thigh perforator flap pedicled with oblique branch trunk of lateral circumflex femoral artery in the muscular septum].

Objective: To explore the anatomical characteristics of the anterolateral thigh perforator flap pedicled with oblique branch trunk of lateral circumflex femoral artery in the muscular septum and the clinical effect of this flap in repairing skin and soft tissue defects in the extremities. Methods: A retrospective observational study was conducted. From December 2020 to April 2021, 59 patients with skin and soft tissue defects in the extremities admitted to the Department of Hand Surgery of Suzhou Ruihua Orthopaedic Hospital met the inclusion criteria, including 46 males and 13 females, aged 20 to 81 years. The wound area after debridement ranged from 8 cm×5 cm to 38 cm×20 cm. According to the condition of the wound, the perforators in the anterolateral femoral region on the unaffected side were located by color Doppler ultrasound. The anterolateral thigh perforator flap with the oblique branch of lateral circumflex femoral artery as the source artery was designed, and the wound was repaired by unilateral flap or series combination of bilateral flaps (with the area of unilateral flap ranging from 7 cm×5 cm to 37 cm×11 cm). The wound of the donor site was sutured directly. The following items were recorded, including the number of perforators in the anterolateral femoral region marked before operation, the course characteristics of oblique branch trunk of lateral circumflex femoral artery and its perforators, and the number, origin, and type of perforators observed during operation, the flap repair mode and the flap harvest time. After operation, the survival condition of the flap, the wound healing time in the recipient site, and the suture healing in the donor area were observed, and the recovery of the donor and recipient areas was followed up. At the last follow-up, the sensation function evaluated by sensory rating scale of British Medical Research Association and two-point discrimination of the area transplanted with flap were recorded, and the improved comprehensive curative effect evaluation scale of flap was used to evaluate the repair effect of the flap. Results: A total of 156 perforators were marked in the anterolateral femoral region before operation, and 144 perforators were observed during the operation, of which 98 came from the oblique branch of the lateral circumflex femoral artery, and the first perforator of the oblique branch was the intermuscular septal perforator. Once formed, most oblique branch trunk of lateral circumflex femoral artery in the muscular septum could be divided into the deep branch and the superficial branch at the middle and upper 1/3 junction of the line between the anterior superior iliac spine and the lateral edge of the patella, the deep branch mainly ran in the muscle of vastus intermedius and vastus lateralis, and rarely developed the skin perforators, while the superficial branch mainly ran in the muscular septum between the rectus femoris and the vastus lateralis, and grew out the perforators to the proximal skin of the anterolateral femoral region. Fifty-six patients were repaired with unilateral flap and 3 patients with bilateral flap in series combination, with the harvesting time of the unilateral flap ranged from 9 to 99 min. Three patients developed arterial crisis within 48 hours after operation and survived after timely exploration; the flap of 1 patient developed necrosis 11 days after operation and was repaired by abdominal split-thickness skin graft; the other flaps survived smoothly. The wound healing time in the recipient area was 10 to 42 days after operation, and the sutures in the donor area healed well. During the follow-up of 6 to 10 months, 8 patients underwent thinning and plastic surgery 6 months after operation because of bloating in the flap transplantation area, while the other patients had a good shape of the flap transplantation area, with no deep tissue infection such as osteomyelitis, with soft texture, good elasticity, no pain, and good blood circulation; all the donor areas were left with linear scars, normal blood circulation in the distal extremities, no limitation of knee joint motion or quadriceps muscle strength. At the last follow-up, the sensation function was restored in the flap transplantation area of the affected limb, including 14 cases of S1 grade and 45 cases of S2 grade; there was only one point of two-point discrimination; the curative effect evaluation of flap repair included excellent in 24 cases, good in 35 cases, and general in 3 cases. Conclusions: The anterolateral thigh perforator flap pedicled with oblique branch trunk of lateral circumflex femoral artery in the muscular septum has the advantages of relatively concealed donor area, large cutting width, and simple operation during surgery. It protects the donor area to the greatest extent while repairing skin and soft tissue defects in the extremities, and is a useful supplement to the classic anterolateral thigh perforator flap.

Negative Goos-Hänchen shift on a concave dielectric interface.

We study the Goos-Hänchen shift (GHS) on a curved surface through numerical simulation by the boundary element method. A negative GHS is first discovered on a concave dielectric interface below the critical angle, accompanied by a large positive GHS on the convexity. The simulation shows that the GHS on a planar interface is the composition of the GHS from a concave and the corresponding convex interface. This work will enrich the study of the GHS for different curved surfaces, which will have potential applications in micro-optics and near-field optics.

Broadband integrated polarization beam splitter with surface plasmon.

A broadband integrated waveguide polarization beam splitter consisting of a metal nanoribbon and two dielectric waveguides is proposed and numerically investigated. This surface plasmon based device provides a unique approach for polarization sensitive manipulation of light in an integrated circuit and will be essential for future classical and quantum information processes.

Stimulated emission as a result of multiphoton interference.

By performing an experiment on stimulated emission by two photons in the parametric amplification process and comparing it to a three-photon interference scheme, we present evidence in support of the idea that the underlying physics of stimulated emission is simply the constructive interference due to photon indistinguishability. So the observed signal enhancement upon the input of photons can be interpreted as a result of multiphoton interference of the input photons and the otherwise spontaneously emitted photon from the amplifier.

An 8×8 Row-Column Summing Readout Electronics for Preclinical Positron Emission Tomography Scanners.

This work presents a row/column summing readout electronics for an 8×8 silicon photomultiplier array. The summation circuit greatly reduces the number of electronic channels, which is desirable for pursuing higher resolution positron emission tomography scanners. By using a degenerated common source topology in the summation circuit, more fan-in is possible and therefore a greater reduction in the number of electronic channels can be achieved. The timing signal is retrieved from a common anode, which allows the use of a single fast-sampling analog to digital converter (ADC) for the timing channel and slower, lower power ADCs for the 64 spatial channels. Preliminary results of one row summation of the 8×8 readout electronics exhibited FWHM energy resolution of 17.8% and 18.3% with and without multiplexing, respectively. The measured timing resolution is 2.9ns FWHM.

Four-photon interference with asymmetric beam splitters.

Two experiments of four-photon interference are performed with two pairs of photons from parametric downconversion with the help of asymmetric beam splitters. The first experiment is a generalization of the Hong-Ou-Mandel interference effect to two pairs of photons while the second one utilizes this effect to demonstrate a four-photon de Broglie wavelength of lambda/4 by projection measurement.

Demonstration of temporal distinguishability in a four-photon state and a six-photon state.

An experiment is performed to demonstrate the temporal distinguishability of a four-photon state and a six-photon state, both from parametric down-conversion. The experiment is based on a multiphoton interference scheme in a recently discovered projection measurement of a maximally entangled N-photon state. By measuring the visibility of the interference dip, we can distinguish the various scenarios in the temporal distribution of the pairs and, thus, quantitatively determine the degree of temporal distinguishability of a multiphoton state.

Analysis of Mycoplasma hyorhinis DNA in the presence of host cells without growing the mycoplasma axenically.

Mycoplasma hyorhinis coisolates with the mitochondria of the cells in which it is carried as an infection. Since both mitochondria and mycoplasmas synthesize DNA by using the prokaryotic DNA polymerase gamma, the use of aphidicolin, which inhibits eukaryotic DNA polymerase alpha, allows for selective synthesis of mycoplasmal and mitochondrial DNA. The restriction patterns of mitochondria and mycoplasmas can easily be differentiated from each other in mixtures of both DNAs. Thus, it is possible to study the molecular biology of this noncultivable mycoplasma in situ rather than after growth in artificial media, with its potential genetic consequences during adjustment to axenic growth.