Haw Yen Chiu

Free anterolateral thigh flap for reconstruction of head and neck defects following cancer ablation

Thirty-seven consecutive free anterolateral thigh flaps in 36 patients were transferred for reconstruction of head and neck defects following cancer ablation between January of 1997 and June of 1998. The success rate was 97 percent (36 of 37), with one flap lost due to a twisted perforator. The anatomic variations and length of the vascular pedicle were investigated to obtain better knowledge of anatomy and to avoid several surgical pitfalls when it is used for head and neck reconstruction. The cutaneous perforators were always found and presented as musculocutaneous or septocutaneous perforators in this series of 37 anterolateral thigh flaps. They were classified into four types according to the perforator derivation and the direction in which it traversed the vastus lateralis muscle. In type I, vertical musculocutaneous perforators from the descending branch of the lateral circumflex femoral artery were found in 56.8 percent of cases (21 of 37), and they were 4.83 ± 2.04 cm in length. In type II, horizontal musculocutaneous perforators from the transverse branch of the lateral circumflex femoral artery were found in 27.0 percent of cases (10 of 37), and they were 6.77 ± 3.48 cm in length. In type III, vertical septocutaneous perforators from the descending branch of the lateral circumflex femoral artery were found in 10.8 percent of cases (4 of 37), and they were 3.60 ± 1.47 cm in length. In type IV, horizontal septocutaneous perforators from the transverse branch of the lateral circumflex femoral artery were found in 5.4 percent of cases (2 of 37). They were 7.75 ± 1.06 cm in length. The average length of vascular pedicle was 12.01 ± 1.50 cm, and the arterial diameter was around 2.0 to 2.5 mm; two accompanying veins varied from 1.8 to 3.0 mm and were suitable for anastomosis with the neck vessels. Reconstruction of one-layer defect, external skin or intraoral lining, was carried out in 18 cases, through-and-through defect in 17 cases, and composite mandibular defect in two cases. With increasing knowledge of anatomy and refinements of surgical technique, the anterolateral thigh flap can be harvested safely to reconstruct complicated defects of head and neck following cancer ablation with only minimal donor-site morbidity.

Distally based anterolateral thigh flap: an anatomic and clinical study.

The distally based anterolateral thigh flap has been used for coverage of soft-tissue defects of the knee and upper third of the leg. This flap is based on the septocutaneous or musculocutaneous perforators derived from the lateral circumflex femoral system. The purpose of this study was to examine the results of anatomical variations of the descending branch of the lateral circumflex femoral artery and the retrograde blood pressure of the descending branch of the lateral circumflex femoral artery so that the surgical technique for raising and transferring a distally based anterolateral thigh flap to the knee region could be improved. The authors have actually used this flap in three cases. In 11 thighs of six cadavers, the descending branch of the lateral circumflex femoral artery had a rather consistent connection with the lateral superior genicular artery or profunda femoral artery in the knee region. The pivot point, located at the distal portion of the vastus lateralis muscle, ranges from 3 to 10 cm above the knee. In their three cases, the maximal flap size was 7.0 × 16.0 cm and was harvested safely, without marginal necrosis. The mean pedicle length was 15.2 ± 0.7 cm (range, 14.5 to 16 cm). The average proximal and distal retrograde blood pressure of the descending branch of the lateral circumflex femoral artery was also studied in another 11 patients, and the anterolateral thigh flap being used for reconstruction of head and neck defects showed 58.3 and 77.7 percent of proximal antegrade blood pressure, respectively. The advantages of this flap include a long pedicle length, a sufficient tissue supply, possible combination with fascia lata for tendon reconstruction, and favorable donor-site selection, without sacrifice of major vessels or muscles.

Angiogenin expression in burn blister fluid: Implications for its role in burn wound neovascularization

Deep partial thickness burn (DPTB) wound fluids have a greater propensity for establishing neovascularization than did superficial partial thickness burn (SPTB) wound fluids in our previous study. To investigate the factors responsible for this activity, cytokine array and enzyme‐linked immunosorbent assay were used to perform an expression analysis of angiogenic factors in burn fluid. Although present in approximately equal amounts in both SPTB and DPTB blister fluids from burn patients, angiogenin does appear to be involved in the ability of DPTB blister fluid to promote neovascularization in vitro and in vivo. Angiogenin alone was sufficient to induce endothelial differentiation of circulating angiogenic cells (CAC) without vascular endothelial growth factor A involvement. In addition, angiogenin was positively associated with CAC differentiation in the burn blister fluid. Blocking the effect of angiogenin in burn blister fluids resulted in a significant reduction of endothelial cell proliferation, CAC differentiation, and new blood vessels formation in vivo. Moreover, immunohistochemistry revealed that high angiogenin expression colocalizes with high vascularity in human burn wounds at day 7, further supporting our hypothesis that angiogenin is involved in burn wound neovascularization.

Clinical application of computerized evaluation and re-education biofeedback prototype for sensorimotor control of the hand in stroke patients

BackgroundHemianaesthesia patients usually exhibit awkward and inefficient finger movements of the affected hands. Conventionally, most interventions emphasize the improvement of motor deficits, but rarely address sensory capability and sensorimotor control following stroke. Thus it is critical for stroke patients with sensory problems to incorporate appropriate strategies for dealing with sensory impairment, into traditional hand function rehabilitation programs. In this study, we used a custom-designed computerized evaluation and re-education biofeedback (CERB) prototype to analyze hand grasp performances, and monitor the training effects on hand coordination for stroke patients with sensory disturbance and without motor deficiency.MethodsThe CERB prototype was constructed to detect momentary pinch force modulation for 14 sub-acute and chronic stroke patients with sensory deficiency and 14 healthy controls. The other ten chronic stroke patients (ranges of stroke period: 6–60u2009months) were recruited to investigate the effects of 4-weeks computerized biofeedback treatments on the hand control ability. The biofeedback procedures provide visual and auditory cues to the participants when the interactive force of hand-to-object exceeded the target latitude in a pinch-up-holding task to trigger optimal motor strategy. Follow-up measurements were conducted one month after training. The hand sensibility, grip forces and results of hand functional tests were recorded and analyzed.ResultsThe affected hands of the 14 predominant sensory stroke patients exhibited statistically significant elevation in the magnitude of peak pinch force (pu2009=u20090.033) in pinching and lifting-up tasks, and poor results for hand function tests (pu2009=u20090.005) than sound hands did. In addition, the sound hands of patients were less efficient in force modulation (pu2009=u20090.009) than the hands of healthy subjects were. Training with the biofeedback system produced significant improvements in grip force modulation (pu2009=u20090.020) and better performances in the subtests of pin insertion (pu2009=u20090.019), and lifting of lightweight objects (pu2009=u20090.005).ConclusionsThe CERB prototype can provide momentary and interactive information for quantitative assessing and re-educating force modulation appropriately for stroke patients with sensory deficits. Furthermore, the patients could transfer the learned strategy to improve hand function.

Deep partial thickness burn blister fluid promotes neovascularization in the early stage of burn wound healing

The effect of burn blister fluid in neovascularization during burn wound healing is unknown. Burn blister fluid, containing a large amount of chemokines, is thought to play a role in the early stage of neovascularization. This process includes angiogenesis and vasculogenesis. Because of different healing time of burn wounds, we hypothesized that neovascularization in superficial partial thickness burn (SPTB) and deep partial thickness burn (DPTB) wounds were different. The neovasculogenic effects of two different burn blister fluids were also different. We found Day 7 DPTB wounds had a significant increase in blood vessels compared with SPTB wounds by immunohistochemistry. DPTB blister fluid significantly promoted neovascularization via increasing endothelial cell proliferation, and migration and differentiation of circulating angiogenic cells relative to SPTB blister fluids. In the animal study, DPTB blister fluids markedly promoted new blood vessel formation compared with those from SPTB blister fluids using in vivo Matrigel plug assay. These results suggest that DPTB wounds require more new vessel formation than SPTB. Furthermore, the measurement of angiogenic activities in burn blister fluids serves as a possible tool for assessing burn wound status.

Functional Sensibility Assessment. Part I: Develop a Reliable Apparatus to Assess Momentary Pinch Force Control

A precise magnitude and timing control of pinch performance is based on accurate feed‐forward and feedback control mechanisms. Ratio of peak pinch force and maximum load force during a functional performance is a sensitive parameter to reflect the ability to scale pinch force output according to actual loads. A pinch apparatus was constructed to detect momentary pinch force modulation of 20 subjects with normal hand sensation. The results indicated high intra‐class correlation coefficient and small coefficient of variation of the detected force ratio among three repeated tests, which represented that the stability test of the measured response confirmed the feasibility of this apparatus. The force ratio for a 480 g object with a steel surface ranged between 1.77 and 1.98. Normal subjects were able to scale and contribute pinch force precisely to a pinch‐holding‐up test. This study may provide clinicians a reliable apparatus and method to analyze the recovery of functional sensibility in patients with nerve injuries.

Prognostic factor of mortality and its clinical implications in patients with necrotizing fasciitis caused by Vibrio vulnificus

In Taiwan, the aquatic environment and endemic hepatitis contribute to the high susceptibility of Vibrio vulnificus infection. A multidisciplinary treatment protocol for necrotizing fasciitis caused by V. vulnificus was developed in our institute, namely, ceftriaxone or ceftazidime combined with doxycycline or minocycline followed by an emergency fasciotomy and intensive care unit admission. We retrospectively reviewed 100 cases to evaluate the effectiveness of our treatment protocol and identify independent predictors of mortality to improve clinical outcomes. Cases of culture-confirmed V. vulnificus infection between January 1996 and December 2011 were reviewed. Necrotizing fasciitis was surgically diagnosed if these criteria were met: necrotic fascia, “dishwater discharge”, and loss of resistance while doing finger dissection along the fascia plane. One hundred cases met these criteria and were included for analysis. Eighteen patients died (18xa0% mortality). Unknown injury events, presence of multiple skin lesions, leukocytesu2009<u200910,000 cells/mm3, plateletsu2009<u2009100,000/mm3, serum creatinine ≥1.3xa0mg/dL, serum albuminu2009<u20092.5xa0mg/dL, and delayed treatment beyond 3xa0days post-injury or symptom onset were associated with significantly higher mortality. Multivariate analysis showed that treatment delayed beyond 3xa0days is an independent factor indicating a poor prognosis (OR 10.75, 95xa0% CI 1.02–113.39, pu2009=u20090.048). Early diagnosis and prompt treatment within 3xa0days post-injury or symptom onset should be the goal for treating patients with necrotizing fasciitis caused by V. vulnificus. Additional investigations to rescue patients with a prolonged disease course of necrotizing fasciitis (≥3xa0days) may be important.

Glomus tumor twenty-year experience and literature review

AbstractGlomus tumors are rare, usually benign, vascular hamartomas consisting cells resembling the smooth muscle cells of the normal glomus body. They can be solitary or multiple, whereas solitary tumors are majorly located on the digits. Digital glomus tumors most commonly appear in subungual region and show a strong female predominance. There are several classical symptoms, clinical tests, and imaging tools, such as X-ray, magnetic resonance imaging, and ultrasonography, which can provide good accuracy for clinical diagnosis. However, misdiagnosis and delayed diagnosis are still commonly observed because primary physicians are unfamiliar with classical symptoms and clinical tests. Complete surgical excision often can result in complete relief of symptoms. Recurrence is largely caused by incomplete excision, but repeated image study is recommended to rule out new or malignant lesions. This series is a retrospective review of 50 cases with glomus tumors managed at our institute. We aim to review the key aspects of glomus tumor and provide a simple guideline for earlier diagnosis and treatment.

Correlation of digital sensibility and precision of pinch force modulation in patients with nerve repair

The outcome measures for patients following peripheral nerve repairs commonly include muscle strength and sensory assessments. However, no significant discussion exists on the impact of nerve injury on sensorimotor control. The objective of this longitudinal study was to explore the effects of nerve regeneration on the control of pinch force in executing functional tasks. Seven patients with digital or median nerve repairs were assessed by a custom‐designed pinch device and conventional sensory tools at monthly intervals following nerve repair. These tools measured sensibility, maximum pinch strength, and anticipated pinch force adjustments to movement‐induced load fluctuations in a pinch‐holding‐up activity (PHUA). Six force‐related and temporal parameters for sensory measurement were used to determine improvements in pinch performance over time following sensory recovery. The results revealed significant differences in the parameters of peak pinch force, baseline pinch force, force ratio, and the percentage of maximal pinch force output at different points in the course of nerve regeneration. A strong relationship was also found between kinetic data from the PHUA test and the traditional sensibility tests for the nerve repair patients in the present study.

Ultrasound for schwannoma in the upper extremity

the digital nerves. Clear silver Pacinian corpuscles are encountered and are visible during dissection of the subcutaneous fat as the digital nerve is approached. We have observed that the digital nerve lies directly deep to the plane of the Pacinian corpuscle. We have commonly seen them on the ulnar aspect of the hand, overlying the ring and little finger metacarpals although this may simply reflect the fact that Dupuytren’s disease more commonly affects these areas. The Pacinian corpuscle is clearly visible to the naked eye (Fig 1). Identification of a Pacinian corpuscle therefore alerts the operating surgeon to the proximity of a digital nerve, thus reducing the risk of injury to digital nerves, particularly when they are close to cords of Dupuytren’s tissue.