Rate of Free Flap Failure and Return to the Operating Room in Lower Limb Reconstruction: A Systematic Review.

Background: Soft tissue defects of the lower limbs pose significant challenges in reconstructive surgery, accounting for approximately 10% of all reconstructive free flaps performed. These reconstructions often encounter higher complication rates due to various factors such as inflammation, infection, impaired blood flow, and nerve injuries. Methods: A systematic review was conducted following PRISMA guidelines, reviewing literature from 2017 to 2024. Eligible studies included those on free flap reconstruction of lower limb defects in living human subjects, with more than three cases and reported rates of flap failure and return to the operating room. Systematic reviews and metanalysis were excluded. Results: A total of 17 studies comprising 5061 patients and 5133 free flap reconstructions were included. The most common defects were in the lower leg (52.19%) due to trauma (79.40%). The total flap necrosis rate was 7.78%, the partial necrosis rate was 9.15%, and the rate of return to the operating room for suspected vascular compromise was 13.79%. Discussion: Lower limb reconstruction presents challenges due to diverse etiologies and variable tissue requirements. Factors such as recipient vessel availability, flap selection, and multidisciplinary approaches influence outcomes. Muscle and fasciocutaneous flaps remain common choices, each with advantages and limitations. This systematic review underscores the importance of individualized treatment planning. Conclusions: Microsurgical reconstruction of lower limb defects demonstrates safety and reliability, with overall favorable outcomes. Flap selection should be tailored to specific patient needs and defect characteristics, emphasizing meticulous surgical techniques and multidisciplinary collaboration. This systematic review provides valuable insights into current standards and encourages adherence to best practices in lower limb reconstruction.

Surgical Management of Patients with Parotid Involvement from Non-Melanoma Skin Cancer of the Head and Neck.

We conducted a retrospective, longitudinal study on a single-center series of patients who underwent parotidectomy in the management of advanced head and neck non-melanoma skin cancer (hnNMSC). The aim of this study was to identify prognostic factors associated with worse outcomes. Forty-one men and nine women were included. The mean age at the time of surgery was 78.9 years. The 5-year overall survival, disease-specific survival, locoregional recurrence-free survival, and distant metastasis-free survival calculated with Kaplan-Meier curves were 39.9%, 56.3%, 58.6%, and 82.1%, respectively. A univariate analysis showed that the status of the margins, facial nerve direct involvement, lymph vascular invasion, and histological grading were associated with worse outcomes (p < 0.05). Positive margins were associated with worse disease-specific survival also in a multivariate analysis (p = 0.001, HR = 32.02, and CIs 4.338 to 351.3). Because the resection in free margins is the most important prognostic factor, early diagnosis or, in the case of advanced disease, extensive surgical resection with concomitant reconstruction is needed. Adjuvant therapy is indicated in selected cases.

The profunda artery perforators: Anatomical study and radiological findings using computed tomography angiography in patients undergoing PAP flap breast reconstruction.

BACKGROUND: The popularity of the profunda femoris artery perforator (PAP) flap is increasing; however, knowledge concerning the standardization of radiological findings and their clinical implications is limited. We evaluated the radiological architecture of posterior thigh perforators using Computed Tomography Angiography (CTA) to identify landmarks to facilitate flap dissection. METHODS: A retrospective study was conducted on 35 patients who underwent unilateral breast reconstruction with a PAP flap. The preoperative CTA scans were analyzed, and the perforator characteristics were evaluated. The perforators were mapped using a Cartesian coordinate system. Data were normalized by anatomical landmarks and overlapped. Perioperative and postoperative results were analyzed. Radiological and intraoperative were compared. RESULTS: Two CTA scans were excluded; 66 thighs were examined. The mean perforator number was 3.2. The mean diameter of chosen perforators was 2.7 mm (DS ± 0.6 mm) at the origin, 2.2 mm (DS ± 0.4 mm) at the adductor space midpoint, and 1.7 mm (DS ± 0.3 mm) at the deep fascia. The mean adipose tissue thickness was 3.35 cm (DS ± 0.94) at the deep fascia and 3.59 cm (DS ± 1.19) at the adductor space midpoint. Intraoperatively, the perforator was located 3.22 cm (DS ± 0.87) from the posterior border of the gracilis muscle and 8.98 cm (DS ± 1.44) from the inferior gluteal crease. A radiological area located 9.33 cm (DS ± 4.81) from the y-axis and 7.48 cm (DS ± 1.88) from the x-axis was identified. CONCLUSIONS: CTA using the volume-rendering technique is a valuable method to study in vivo the radiological anatomy of the posterior thigh perforators.

Superficial outside-flap shunt (SOS) is associated with a low incidence of postoperative DIEP flap venous congestion: A single-institution retrospective cross-sectional study.

INTRODUCTION: Venous congestion burdens up to 15% of deep inferior epigastric artery perforator (DIEP) flap breast reconstructions. For these cases, venous augmentation by superficial outside shunt (SOS) is associated with 100% success in secondary salvage surgeries. Intraoperative venous augmentation using other techniques yields a 0.3% rate of return to theater due to venous congestion, but there is no evidence assessing the effectiveness of the SOS technique applied preventively. Comparing this preventive approach to data prior to its implementation, we expect to find a reduced number of venous congested flaps with reduced flap losses and revision surgeries. PATIENTS AND METHODS: This retrospective cross-sectional study involved DIEP flap breast reconstructions performed between 2011 and 2020. The control group included patients receiving additional venous anastomosis as a secondary salvage procedure. The "preventive SOS group" included patients who received preventive SOS during the main surgery. Age, body mass index (BMI), pregnancies, perioperative treatments (neoadjuvant or adjuvant chemo or radiotherapy), follow-up complications (arterial ischemia, venous congestion, hematomas, partial/total flap loss), and revision surgeries (breast debridement, flap remodeling) were recorded and compared. RESULTS: Within 695 flaps performed, 397 flaps were included in the control group, and 298 flaps were included in the preventive SOS group. The groups were homogeneous for age (p = 0.418), BMI (p = 0.747), and flap weight (p = 0.064). Fifty-one flaps (12.8%) in the control group compared to zero (0.0%) in the preventive SOS group required return to theater (p < 0.001). CONCLUSIONS: We reported encouraging preliminary results for SOS to prevent DIEP flap venous congestion. These results must be validated prospectively.

Narrow inferior-central septum-based pedicle: A safe technique to improve aesthetic outcomes in breast reduction.

BACKGROUND: Inferior-central pedicle has some aesthetic drawbacks, including hypertrophic scar along the inframammary fold (IMF), squaring of the breast contours, and propensity to develop long-term 'bottoming-out.' This study aimed to verify if the narrow inferior-central (NIC) septum-based pedicle can allow the surgeon to improve aesthetic outcomes compared with the traditional inferior-central pedicle approach. METHODS: Forty breasts underwent NIC-based breast reduction (group A), and 37 underwent traditional inferior-central pedicles (group B). The NIC pedicle was drawn with a width of 3.5-4.5 cm. The recorded measurements were sternal notch to nipple distance (S-N) and nipple to IMF distance (N-IMF) at the time of preoperative markings and follow-up 1, 6, and 18 months after the procedure. RESULTS: The two groups were homogeneous regarding demographics, operative data, and preoperative S-N and N-IMF distances. Both groups showed no total or partial nipple-areola necrosis. At the 18-month follow-up, S-N (p < 0.00001) and N-IMF (p = 0.00039) distances were statistically different between the two groups, in favour of NIC group A. Changes in N-IMF distances between the 1- and 18-month visits were statistically different among groups (p < 0.0001), with a length variation of + 17.51% and + 28.46%, respectively. Patient satisfaction rate regarding "breast shape" (p = 0.021), "lower pole appearance" (p = 0.00017), and "scar" (p = 0.047) were higher in group A. CONCLUSION: NIC-based pedicle proved to be a safe procedure and allowed us to overcome limitations that typically characterise the inferior pedicle, i.e., 'bottoming-out' deformity, hypertrophic scar of the lower pole, and squaring of the breast contours. LEVEL OF EVIDENCE: II.

Survival in Patients with Primary Parotid Gland Carcinoma after Surgery-Results of a Single-Centre Study.

This study aims to analyse a single-centre cohort series of patients who underwent parotidectomy for primary malignant parotid tumours. A retrospective chart review of 64 consecutive patients treated from November 2010 to March 2022 was performed. Outcomes were analysed by Kaplan-Meier curves. Sixty-four patients with a primary parotid malignancy were included in the study, with one bilateral case in this cohort. Patients were classified as stage I-II in 39 cases and stage III-IV in 26 cases. The five-year overall survival (OS), disease-specific survival (DSS), local relapse-free survival (LRFS), and distant metastasis-free survival (DMFS) rates were 78.4%, 89%, 92.5%, and 87.1%, respectively. Univariate analysis showed that high-risk histology, stage IV disease, lymphovascular invasion, perineural invasion, node metastasis, skin involvement, facial nerve involvement, and positive or close margins were risk factors associated with poorer outcomes. At present, the best evidence suggests that radical surgery should be the standard approach, and adjuvant therapy, in terms of radiotherapy/chemoradiotherapy, is recommended in patients with risk factors.

Free-style technique versus computed tomographic angiography-guided perforator selection in deep inferior epigastric perforator flap harvest: A prospective clinical study.

BACKGROUND: Computed tomographic angiography (CTA) is the preferred diagnostic tool in preoperative deep inferior epigastric perforator (DIEP) flap assessment, though some surgeons prefer approaching perforator selection with intraoperative findings alone. METHODS: This prospective observational study conducted between 2015 and 2020 assessed our intraoperative decision-making "free-style" technique for DIEP flap harvest. Any patient with indication for immediate or delayed breast reconstruction using abdominally based flaps and who received preoperative CTA was enrolled. Only unilateral cases performed by the same surgeon were considered. Allergy to iodine-based contrast media, renal impairment and claustrophobia were other exclusion criteria. Primary endpoint consisted in comparing operative times and complication rates between free-style technique and CTA-guided approach. Secondary endpoints included evaluation of agreement rate between intraoperative findings and CTA, and identification of variables affecting operative time and complication rate. Demographics, surgical information, agreement versus non-agreement and complications were collected. RESULTS: Starting from 206 patients, 100 were enrolled. Fifty were assigned to Group A, receiving DIEP flap with free-style technique. The other 50 were assigned to Group B, receiving DIEP flap with CTA-guided perforators selection. Study groups' demographics were homogenous. Operative time was statistically lower (p = .036) in free-style group (252.4 ± 44.77 min vs. 265.6 ± 31.67 min). Complication rates were higher in CTA-guided group (10% vs. 2%) though this was not significant (p = .092). Overall agreement rate in dominant perforator selection between intraoperatively and CTA-based assessment was 81%. Multiple regression analysis showed no variable increased complication rate, though CTA-guided approach, BMI > 30 and harvesting more than one perforator were respectively associated with B-coefficient of 17.391 (2.430-32.351, 95% CI) [p = .023], 3.50 (0.640-6.379, 95% CI) [p = .017] and 18.887 (6.232-31.542, 95% CI) [p = .004], predicting increased operative time. CONCLUSIONS: The free-style technique proved to be a useful tool for guiding DIEP flap harvest with good sensibility in detecting the dominant perforator suggested by CTA without statistically increasing surgery duration and complications.

Perforator-based chimeric anterolateral thigh flap U-shaped insetting for total pharyngoesophageal reconstruction: Surgical technique and functional outcomes.

BACKGROUND: Pharyngoesophageal reconstruction with the tubed anterolateral thigh (ALT) flap is burdened by possible strictures and pharyngocutaneous fistulae (PCF). We present our experience with the U-shaped insetting of perforator-based chimeric ALT flap focusing on surgical technique, complications and functional outcomes. METHODS: We retrospectively included 10 patients with a total circumferential defect of the hypopharynx undergoing reconstruction with ALT flap. A perforator-based chimeric ALT flap with two independent skin paddles was harvested: the trapezoid paddle with the greater base cranially and the height oriented vertically was used for pharyngoesophageal reconstruction while the second paddle was exteriorized and used for flap monitoring and reducing tension on skin closure. Mean age was 56.4 years. Eight patients were affected by squamous cell carcinoma. Modified barium swallow radiogram and fiberoptic laryngoscopy were performed to assess strictures and PCFs. Swallowing and speech outcomes were evaluated through the Deglutition Handicap Index (DHI), M.D. Anderson Dysphagia Inventory (MDADI) and Voice Handicap Index (VHI) questionnaires. RESULTS: Mean flap dimension was 7.9 × 6 × 9.2 cm. Mean ischemia time was 58.2 min (range 42-80). No flap loss nor flap-related complications were reported. Two PCFs were observed. Fiberoptic laryngoscopy documented a complete integration of the flap with no strictures or stenosis. Mean follow-up was 13.6 months (range 1-45 months). Mean DHI score was 33.8, mean MDADI score was 62.5, mean VHI score was 32.2. CONCLUSIONS: The ALT flap U-shaped insetting is a reliable option for pharyngoesophageal reconstruction yielding a high success rate, low number of strictures and fistulae and good swallowing and voice outcomes.

Unilateral immediate deep inferior epigastric artery perforator flap breast reconstruction following skin sparing mastectomy: A comparative study on revision surgeries to improve breast symmetry.

BACKGROUND: The number of revision surgeries to improve breast asymmetry after deep inferior epigastric perforator (DIEP) flap breast reconstruction is still high worldwide with impact on both patients and healthcare systems. These procedures include fat grafting, contralateral breast symmetrization, scar revision, flap repositioning and remodeling. A previously published DIEP flap insetting algorithm has proven to be effective in selecting patient-tailored strategies to achieve excellent aesthetic outcomes. This study investigated whether this insetting algorithm was effective in reducing revision surgeries in patients undergoing SSM and immediate DIEP flap breast reconstruction to achieve the goal of a one-stage reconstruction. METHODS: This retrospective case-control study included 60 patients (group A) treated without the DIEP flap standardized insetting algorithm and 60 patients (group B) treated with the standardized insetting algorithm, which considers among its variables the type of breast to be reconstructed, abdominal tissue thickness, rotation due to harvesting side. Demographic data, operative data, complications and number of revision surgeries were recorded. RESULTS: One hundred and twenty primary and 106 revision surgeries were performed. Groups were homogenous for age (p = .32), body mass index (p = .77), flap weight (p = .7), operative time (p = .87) and early complications (p = .78). When excluding isolated nipple reconstruction from the revision surgeries, one-stage reconstruction was successfully performed in 26 patients in group A (43.3%) and 39 patients (65.0%) in group B, with a statistically significant difference between the groups (p = .003). CONCLUSIONS: The introduction of a standardized insetting algorithm for immediate unilateral DIEP flap breast reconstruction can be effective in reducing the number of revision surgeries for breast asymmetry, making a one-stage reconstruction an achievable and reliable target.

The profunda artery perforator flap for upper limb reconstruction: A case report and literature review on the flap applications in reconstruction.

The profunda femoris artery perforator (PAP) flap has been recently popularized as an alternative option for microsurgical reconstruction. The use of PAP flap has never been reported and described for reconstruction of the upper extremities, in particular the forearm. The purpose of this case report is to describe a case suggesting the PAP flap as a further reconstructive option in the upper limb. A 16-year-old girl who sustained a traumatic injury to her right dominant forearm resulting in subtotal circumferential tissue loss following a road traffic accident was referred to the authors' department 2 years post-trauma. The disabling fibrotic sequelae on her volar forearm (15 × 10 cm) resulted in a nonfunctional hand. She was unable to perform any active movement of her wrist or digits. Passive movements in the finger joints were preserved. Following debridement and reconstruction of nerves and tendons, soft tissues were resurfaced with a PAP flap. The transverse skin paddle, 12 × 7 cm, was placed distally with the adipofascial portion positioned proximally above the muscle bellies and anastomoses site. A small raw area (4 × 3 cm) was covered with an acellular dermal matrix (ADM). The postoperative course was uneventful. At 9 months postoperatively, the patient demonstrated active flexion and extension of the fingers with independent function. The patient reported satisfaction with the flap donor site and forearm resurfacing. The PAP flap can be a further option for areas requiring soft tissue coverage in patients refusing visible scars. This flap had both the advantage of reducing the morbidity and visibility of the donor site, as well as the ability to resurface a large recipient site with soft and pliable tissue, covering exposed nerves and tendons.

Breast reconstruction using the profunda artery perforator (PAP) flap: Technical refinements and evolution, outcomes, and patient satisfaction based on 116 consecutive flaps.

INTRODUCTION: When a deep inferior epigastric artery flap is not suitable, the profunda artery perforator (PAP) flap can be a good alternative for autologous breast reconstruction. Popularity of the PAP flap is expanding, but it is still only slowly being adopted worldwide. We report our experience with 116 consecutive PAP flaps showing refinements and evolution of the technique towards improvement in outcomes and patients' satisfaction. METHODS: We prospectively collected data from consecutive PAP flap breast reconstructions performed from 2016 to 2019. Patients' demographics, pre-, intra-, postoperative data, and revision procedures were analyzed. The BREAST-Q and a specific questionnaire investigating outcomes at the donor site were completed preoperatively and 12 months postoperatively. RESULTS: One-hundred and sixteen PAP flaps were performed in 86 patients, 64 unilateral and 22 bilateral breast reconstructions. Mean body mass index was 24.72 kg/m2 (range 18.9-29.2) and mean flap weight was 251.30 g (range 152-455 g). Complications included donor site hematoma (1.7%), seroma (2.6%), fat necrosis (1.7%), and wound dehiscence (2.6%). No arterial/venous thrombosis nor flap losses were recorded. Patients reported high satisfaction in all BREAST-Q domains, with mean postoperative scores being higher than preoperative ones, suggesting a positive effect in quality of life and satisfaction. Scores were significant in the satisfaction with breast domain (p = 0.0016). CONCLUSIONS: Breast reconstruction with PAP flap yields a high success, low complications, and excellent cosmetic outcomes in the breast and donor sites. It improves patients' satisfaction and quality of life; hence, it can be considered an excellent option for autologous breast reconstruction.

Septum-Based Mammaplasties: Surgical Techniques and Evaluation of Nipple-Areola Sensibility.

BACKGROUND: The aim of the study was to describe details of surgical techniques and objectively evaluate nipple-areola (NAC) sensibility and viability of septum-based mammaplasties compared to not septum-based reduction techniques. METHODS: Data regarding NAC sensibility for static and moving one- and two-point discrimination were prospectively collected from 63 active group hypertrophic-breasted patients undergoing septum-based reduction mammaplasty preoperatively, at 6 and 12 months postoperatively, and from a control group of 60 patients who underwent not septum-based techniques. Fixed and mixed effect models were used for statistical analysis. RESULTS: Comparison of complications showed no significant differences between groups (p = 0.07). After adjusting the results of the active group according to type of sensory testing, it emerged that the threshold decreases by 10% (p = 0.0003) at 6 months and even reaches 43% (p < 0.0001) at 12 months. The results have been modulated according to age, since the variation is less marked when age increased, by 0.6% at 6 months and 0.8% at 12 months (p = 0.019). The effects of the BMI can only be seen at 12 months, with an increase by 1.3% per year (p = 0.033). Among septum-based techniques, the inferior-central pedicle showed better sensibility outcomes even if not significantly (p = 0.06). Comparison of NAC sensibility outcomes showed that active group had thresholds that were 48% lower when compared to those of the control group at 12 months postoperatively (p < 0.001). CONCLUSION: Septum-based mammaplasty gives optimal results in terms of NAC viability with a significant improvement of sensibility postoperatively. Comparative outcomes on sensibility were also significantly better than not septum-based techniques. LEVEL OF EVIDENCE II: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Double free fillet foot flap: sole of foot and dorsalis pedis in severe bilateral lower extremity trauma, a 10-year follow-up case report.

This study reports a unique 10 years follow-up case of a patient who underwent a free fillet of sole flap for left leg stump coverage and free dorsalis pedis flap for soft tissue reconstruction of contralateral popliteal fossa following severe bilateral lower leg injury.

Complete DIEP flap survival following pedicle resection, 4 years after its transfer. Clinical evidence of autonomization.

We report a case of complete DIEP flap survival, following venous congestion due to the excision of a local recurrence with main pedicle, 4 years after its transfer for breast reconstruction.

Surgical strategies for cutaneous neoplasm of the scalp. State of art.

AIM: Scalp reconstruction has always been a challenging task, in particular after oncological demolition and this article gives an overview on the state of the art in scalp reconstruction strategies. MATERIAL OF STUDY: We elaborated a systematic algorithm for scalp reconstruction based on location and size defects, presence or absence of periosteum, bone involvement, the quality of surrounding scalp tissue, the presence or absence of hair, location of the hairline, patient comorbidities and different procedures commonly used in plastic surgery. RESULTS: Our algorithm allows plastic surgeons to perform scalp reconstruction after the most devastating of defects. DISCUSSION: Successful reconstruction of the scalp requires careful preoperative planning and detailed knowledge of scalp anatomy, hair physiology, variety of available local tissue and plastic surgery procedures as well as synthetic substitutes or products provided by tissue engineering. CONCLUSION: However, the challenge today is to do so with excellent cosmetic results.

Treatment of irradiated expanders: protective lipofilling allows immediate prosthetic breast reconstruction in the setting of postoperative radiotherapy.

BACKGROUND: Immediate two-stage prosthetic breast reconstruction in the setting of postmastectomy radiotherapy (PMRT) currently is hardly achieved with the fast-track expander exchange proposed by Cordeiro and colleagues or the delayed-immediate breast reconstruction proposed by Kronowitz and Robb. Each of these techniques has important drawbacks and complications. To overcome these problems, the authors in 2011 described lipofilling on irradiated expanders in patients undergoing unplanned PMRT (Cagliari University Hospital [CUH] protocol) for early breast cancers with specific risk factors. The authors report their experience after expanding the use of such a protocol for any immediate expander/implant reconstruction in a patient undergoing PMRT. METHODS: The timing for advanced breast cancer involves immediate reconstruction with a tissue expander, complete tissue expansion, radiotherapy (RT) after neoadjuvant chemotherapy starting 2-3 months after mastectomy, one or two fresh fat-grafting sessions at least 6 weeks after RT, and an expander-implant exchange with anterior capsulectomy at least 3 months after the completion of fat grafting. The timing for early breast cancers with specific risk factors involves immediate reconstruction with a tissue expander, complete tissue expansion during postoperative chemotherapy, RT 6 months after mastectomy, one or two fat-grafting sessions 6 weeks after RT, and an expander-implant exchange with anterior capsulectomy at least 3 months after the completion of fat grafting. From 2008 to 2012, 16 patients undergoing total mastectomy and immediate expander-implant breast reconstruction with subsequent PMRT were treated according to the CUH protocol. RESULTS: The results have been extremely encouraging, with rates of ulceration and implant exposure in the radiotreated area dropping to 0 %. These results were retrospectively compared with those for a control group of 16 patients who underwent immediate implantation of an expander. In this latter group, the extrusion rate of the implant in the end was 31.25 %, and this was statistically significant (p < 0.03). The shape and symmetry also were significantly better in the lipofilled patients. CONCLUSION: Protective lipofilling on irradiated expanders appears to be a valid technique for avoiding ulceration and implant exposure after PMRT while allowing a complete expansion. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Intraoperative parathyroid hormone assay during focused parathyroidectomy: the importance of 20 minutes measurement.

BACKGROUND: Parathyroid hormone (PTH) monitoring during the surgical procedure can confirm the removal of all hyperfunctioning parathyroid tissue, as the half-life of PTH is approximately 5 min. The commonly applied Irvin criterion is reported to correctly predict post-operative calcium levels in 96-98% of patients. However, the PTH baseline reference concentration is markedly influenced by surgical manipulations during preparation of the affected glands, interindividual variability of the PTH half-life and modifications in the physiological state of the patient during surgery. The aim of this study was to evaluate the possible impact of the measurement of intraoperative PTH 20 minutes after surgery. METHODS: Between 2003 and 2012, 188 patients underwent a focused parathyroidectomy associated to rapid intraoperative PTH assay monitoring. Blood samples were collected: 1) at pre-incision time, 2) at 10 min after gland excision and 3) at 20 min after excision, if a sufficient reduction of PTH value was not observed. On the bases of the Irvin criterion, an intra-operative PTH drop>50% from the highest either pre-incision or pre-excision level after parathyroid excision was considered a surgical success. RESULTS: A >50% decrease of PTH after gland excision compared to the highest pre-excision value occurred in 156/188 patients (83%) within 10 min and in further 12/188 after 20 minutes (6.4%). In the remaining 20 patients (10.6%) values of PTH remained substantially unchanged or decreased less than 50% and for this reason bilateral neck exploration was performed. An additional pathologic parathyroid was removed in 9 cases, a third in one. In the other 10 cases further neck exploration by a standard cervical approach was negative and in four of these persistent postoperative hypercalcemia was demonstrated. The overall operative success was 97.3%. Intraoperative PTH monitoring was accurate in predicting operative success or failure in 96.3% of patients. CONCLUSIONS: The 20 minutes PTH measurement appears very useful, avoiding unnecessary bilateral exploration and the related risk of complications with only a slight increase of the duration of surgery and of the costs. PTH values decreasing appeared to be influenced by surgical manipulations during minimally invasive parathyroidectomy.