“Microsurgical breast reconstruction - A salvage option for failed implant-based breast reconstruction”

Abstract

Background

The objective of this study was to evaluate microsurgical breast reconstruction as a salvage option for patients with failed implant-based breast reconstruction.

Methods

We conducted a retrospective single-center study including all patients with failed unilateral implant-based breast reconstruction who elected to undergo conversion surgery to microsurgical breast reconstruction from January 2015 to December 2023. Patients were grouped according to the urgency for conversion surgery in the urgent (implant infection or extrusion) or elective (capsular contracture, patients’ desire) group. Both groups were compared.

Results

120 patients were included in the study. 101 patients (84 %) were grouped in the elective group and 19 patients (16 %) in the urgent group. Patient characteristics and intraoperative variables including the utilization of DIEP/MS-TRAM and TMG flap for microsurgical reconstruction were similar in group comparison. Patients in the urgent group had significantly more surgical interventions (3.3 vs. 2.0, p < 0.001) and suffered from significantly more major complications requiring re-operation (32 % vs. 11 %, p = 0.018) compared to the elective group. There was one flap loss in the urgent group (5 % vs. 0 %, p = 0.158).

Conclusion

Microsurgical breast reconstruction is a reliable and safe salvage option in patients with failure of implant-based breast reconstruction. Urgent conversion to microsurgical breast reconstruction due to implant-associated complications, such as infection or extrusion, requires more surgical interventions to achieve successful breast reconstruction and has a higher rate of major complications compared to elective conversion.

Highlights

• •Failure of implant-based breast reconstruction is an increasing challenge.
• •Microsurgical breast reconstruction is a safe salvage option.
• •It overcomes implant-associated complications and reconstructive failure.
• •Urgent conversion due to infection/extrusion requires more surgical interventions.
• •The DIEP/MS-TRAM and TMG flap are both reliable options.

1. Introduction

Since 2020, breast cancer has become the most common new cancer diagnosis around the globe [1]. Mastectomy is a key element of breast cancer surgery and is conducted in about 25 %–30 % of breast cancer patients. Nowadays, there is an appreciation for the psychological impact of the loss of the breast and breast reconstruction has become an integral part of comprehensive breast cancer care in Europe, the USA and high-income countries in Asia [[2], [3], [4], [5]]. The primary surgical options to reconstruct the breast include implants, microsurgical breast reconstruction, hybrid breast reconstruction combining both procedures as well as the valid option to forgo breast reconstruction and ‘going flat’ [6,7]. However, there is a substantial imbalance in clinical practice with implants accounting for 80 % of all breast reconstructions [8]. Implant-based breast reconstruction offers multiple advantages, such as the simplicity of the surgery, no need for a donor-site, fewer complications and re-operations in the short-term, but a higher failure rate and health care costs over time and lower health-related quality of life compared to microsurgical breast reconstruction [[9], [10], [11]].

While breast implants are intended to stay in place for 10–15 years, a considerable subset of patients experience reconstructive failure earlier due to implant-associated complications such as infection, extrusion, rupture or capsular contracture [12,13]. Those complications are often associated with unsightly breast deformity, low skin quality or pain. The implants initially support the breast contour and maximize the breast projection but subsequently thin the delicate skin. Moreover, breast implant-associated anaplastic large-cell lymphoma has become an additional concern.

Microsurgical breast reconstruction is a valuable option to reconstruct the breast with natural appearance and an ultimate reconstructive solution [[14], [15], [16]]. The individual surgical approach allows surgeons to customize the flap in size and shape in order to reconstruct the unique appearance of the breast and natural symmetry. In contrast to breast implants, the well perfused tissue vitalizes the delicate breast skin and replaces the volume and even the lack of skin.

However, adverse breast conditions, in particular implant infection, extrusion or skin necrosis, amplify the urgency and complexity of conversion surgery to microsurgical breast reconstruction. This is a very challenging situation for both the patient and the surgeon. Until now, few articles have been published on this sophisticated topic [[14], [15], [16], [17], [18], [19]].

In this study we compare urgent to elective conversion surgery to microsurgical breast reconstruction in patients with failed implant-based breast reconstruction. This article should support breast surgeons and microsurgeons in meeting the upcoming challenges in reconstructive breast surgery.

2. Patients and methods

2.1. Study design and data acquisition

We conducted a retrospective single-center study that included all patients who underwent conversion surgery from unilateral failed implant-based breast reconstruction to microsurgical breast reconstruction between January 2015 and December 2023. Patients with bilateral breast reconstructions were excluded due to mixed indications (urgent and elective) and variations in preoperative status (e.g., type of mastectomy or reconstruction). The study was conducted in accordance with the Declaration of Helsinki and was approved by the local ethics committee of Rhineland-Palatinate (2024–17877).

Patients were categorized based on the urgency of the conversion surgery into two groups: urgent (implant infection or extrusion) (Fig. 1) and elective (capsular contracture Baker III/IV, patient preference, animation deformity) (Fig. 2).

Fig. 1.

Female patient (52 years, BMI 34,2 kg/m²) diagnosed with invasive ductal breast cancer in the right breast. Following a modified mastectomy and immediate implant-based reconstruction of the right breast, the patient developed radiation dermatitis and implant extrusion in the context of adjuvant radiotherapy. Urgent implant removal and excision of the avital skin was performed followed by staged microsurgical breast reconstruction utilizing the DIEP flap. One year later, the patient received a nipple-areolar reconstruction with a skate flap and skin graft.

(a) preoperative view: Asymmetry of the breast size and shape. Deformed right breast with radiation dermatitis and implant extrusion in the lower quadrants. Natural ptosis of the left breast.

(b) 24 months follow-up: Natural symmetry and appealing contour of both reconstructed breasts. Visible skin substitute of all quadrants of the right breast.

Fig. 2.

Female patient (49 years old, BMI 22.3 kg/m²) diagnosed with unilateral breast cancer in the left breast.

The patient underwent neoadjuvant chemotherapy, nipple-sparing mastectomy and immediate implant-based breast reconstruction as well as adjuvant radiotherapy. The patient developed painful capsular contracture (Baker grade 4). One year after the initial surgery, the patient demanded conversion surgery to natural breast reconstruction. Elective implant removal, capsulectomy and microsurgical breast reconstruction was conducted utilizing the TMG flap to reconstruct the left breast.

(a) preoperative view: Severe deformity of the left breast and asymmetry compared to the natural right breast.

(b) 12 months follow-up: Appealing contour and natural ptosis of the left reconstructed breast. Pleasing symmetry in size and shape of both breasts.

Patients in the urgent group received surgery within 24 h of admission according to our in-house standard.

The electronic inpatient hospital system was screened for data acquisition. Patient characteristics such as age, body mass index (BMI) and comorbidities (diabetes mellitus, obesity, smoking) were extracted. Also, surgical details such as the indication for conversion surgery (urgent vs. elective), the type of mastectomy and implant size were extracted. The primary outcomes included the kind and number of surgeries until successful breast reconstruction (pre-reconstruction surgeries, microsurgical breast reconstruction, re-operations due to postoperative complications, refinement surgeries post-reconstruction), intraoperative details of microsurgical breast reconstruction, major complications of the reconstructed breast requiring re-operation in the postoperative interval and the flap loss rate.

Patients were followed for at least 12 months postoperatively, with regular clinical follow-up visits.

2.2. Statistical analysis

Normally distributed continuous variables were presented as mean ± standard deviation (SD) and categorical variables as frequencies. Categorical variables were compared using the Chi-Square or Fisher's exact test, while non-normally distributed continuous data were analyzed using the Mann-Whitney U test. A p-value of less than 0.05 was considered statistically significant. Data were analyzed using R version 4.1.2 (with the stats and epitools packages, R Core Team 2021).

3. Results

From January 2015 to December 2023, 120 patients underwent conversion surgery to microsurgical breast reconstruction due to unilateral implant failure. The majority of patients (84 %) chose elective implant removal and the minority of patients (16 %) required urgent implant removal.

Patient characteristics are shown in details in Table 1.

Table 1.

Patient characteristics.

Variable	Elective group	Urgent group	Overall	p-value
Patients, n (%)	101 (84 %)	19 (16 %)	120	NA
Age [years], mean ± sd	48 ± 11	51 ± 10	51 ± 10	0.180
BMI [kg/m2], mean ± sd	27.2 ± 5.1	24.8 ± 3.4	26 ± 4.2	0.085
Diabetes mellitus	1 (5 %)	3 (3 %)	4 (3 %)	0.503
Obesity (BMI ≥30 kg/m2)	6 (32 %)	8 (8 %)	14 (12 %)	0.003∗
Active smoker	5 (26 %)	19 (19 %)	24 (20 %)	0.453

n, number; sd, standard deviation.

The prevalence of breast cancer was similar in both groups (p = 1.0). The distribution of primary and recurrent breast cancer (p = 1.0), as well as the use of chemotherapy (p = 0.608) and radiotherapy (p = 0.241), was comparable between both groups. The type of mastectomy and the implant size (p = 0.211) did not differ significantly between both groups. Conversion surgery due to urgent complications was conducted on average 3.8 months following implant-based breast reconstruction and significantly earlier compared to the elective group (p < 0.001).

Breast cancer-related and reconstructive variables are shown in Table 2.

Table 2.

Breast cancer-related and reconstructive variables.

Variable	Elective group	Urgent group	Overall	p-value
Breast cancer, n (%)	85 (84 %)	16 (84 %)	101 (84 %)	1.000
Primary disease	75 (74 %)	14 (74 %)	89 (74 %)	1.000
Recurrent disease	10 (10 %)	2 (10 %)	12 (10 %)
Chemotherapy, n (%)	49 (49 %)	8 (42 %)	57 (48 %)	0.608
Radiotherapy, n (%)	49 (49 %)	12 (63 %)	61 (51 %)	0.241
Type of mastectomy, n (%)
Skin sparing	37 (37 %)	6 (32 %)	43 (36 %)	0.731
Nipple sparing	50 (49 %)	11 (58 %)	61 (51 %)	0.502
Modified radical	14 (14 %)	2 (10 %)	16 (13 %)	1.000
Implant size (cc), mean ± sd	324 ± 118	373 ± 108	331 ± 118	0.211
Implant duration (months), mean ± sd	45.8 ± 48.6	3.9 ± 5.7	39.2 ± 47.2	< 0.001∗

n, number; sd, standard deviation.

The indications for implant removal and conversion surgery are listed in detail in Table 3.

Table 3.

Indications for implant removal and conversion surgery.

	Indications for implant removal	n (%)
Elective group	Capsular contracture (Baker III/IV)	66 (65 %)
	Patients' desire	32 (32 %)
	Animation deformity	3 (3 %)
Urgent group	Implant infection	11 (58 %)
	Implant extrusion	8 (42 %)

The majority of patients in both groups received a single flap for microsurgical breast reconstruction (p = 1.000). In both groups, a few patients required double flaps (bipedicled deep inferior epigastric perforator [DIEP] flap or stacked transverse musculocutaneous gracilis [TMG] flaps) for microsurgical breast reconstruction. The utilization of the DIEP/muscle sparing-transverse rectus abdominis muscle [MS-TRAM] flap and TMG flap (p = 0.782), the mean flap weight (p = 0.912) and the operation time (p = 0.984) of the conversion surgery and were comparable in the urgent and elective group between both groups.

The intraoperative variables of microsurgical breast reconstruction are shown in Table 4.

Table 4.

Intraoperative variables of microsurgical breast reconstruction.

Variable	Elective group	Urgent group	Overall	p-value
Breast reconstruction, n (%)
Single flap	89 (88 %)	17 (89 %)	106 (88 %)	1.000
Double flap	12 (12 %)	2 (11 %)	14 (12 %)
Bipedicled DIEP flap	9	2	11
Stacked TMG flaps	3	0	3
Flap, n (%)
DIEP/MS-TRAM flap	55 (54 %)	11 (58 %)	66 (55 %)	0.782
TMG flap	46 (46 %)	8 (42 %)	54 (45 %)
Mean flap weight (g), mean ± sd	493 ± 287	457 ± 185	462 ± 202	0.912
Operation time (min), mean ± sd	358 ± 111	355 ± 99	357 ± 109	0.984

n, number; DIEP, deep inferior epigastric perforator; MS-TRAM, muscle-sparing – transverse rectus abdominis; TMG, transverse musculocutanous; g, grams; min, minutes; sd, standard deviation.

Postoperative outcomes and complications varied between the groups. Patients in the urgent group had a significantly higher rate of major complications necessitating re-operation of the reconstructed breast compared to the elective group (p = 0.018). Those complications included in the urgent and elective group infection (n = 2 (34 %) vs. n = 0 (0 %)), hematoma (n = 1 (17 %) vs. n = 4 (36 %)), seroma (n = 1 (17 %) vs. n = 2 (18 %), tissue necrosis (n = 1 (17 %) vs. n = 1 (9 %)) and vascular compromise (n = 1 (17 %) vs. n = 4 (36 %)). Vascular compromise led to one flap loss in the urgent group. In group comparison there was no statistical difference (p = 0.158). The urgent group required more often a multi-step approach involving negative pressure wound therapy (NPWT) previous to microsurgical breast reconstruction (p < 0.001). The number of surgical interventions (NPWT cycles) per patient previous to microsurgical breast reconstruction was lower in the elective group without statistical significance (1.0 + ± 0 vs. 1.5 ± 0.6, p = 0.306). The mean number of surgeries per patient was higher in the urgent group compared to the elective group (p < 0.001).

The postoperative outcomes and surgical interventions are shown in Table 5.

Table 5.

Postoperative outcomes and surgical interventions.

Variable	Elective group	Urgent group	Overall	p-value
Major complications breast, n (%)	11 (11 %)	6 (32 %)	17 (14 %)	0.018∗
Flap loss, n (%)	0 (0 %)	1 (5 %)	1 (1 %)	0.158
NPWT (patients), n (%)	2 (2 %)	14 (74 %)	16 (13 %)	<0.001∗
Refinements surgeries (patients), n (%)	54 (53 %)	8 (42 %)	62 (52 %)	0.363
Number of surgeries per patient, mean ± sd	2.0 ± 1.0	3.3 ± 1.6	2.2 ± 1.5	<0.001∗

n, number; NPWT, negative pressure wound therapy; sd, standard deviation.

4. Discussion

Breast reconstruction subsequent to prophylactic or therapeutic mastectomy has the potential to enhance health-related quality of life, and the demand for breast reconstruction continues to rise [20,21]. There is a substantial imbalance in clinical practice with implants accounting for 80 % of breast reconstructions with an ongoing increase [8,20]. The success of implant-based breast reconstruction is substantially based on the viability and quality of the mastectomy flaps covering the implants. Moreover, evident risk factors such as tobacco use, obesity and, in particular, radiotherapy challenge the quality and longevity of implant-based breast reconstruction [22,23].

In this study, 51 % of patients who underwent conversion surgery had received radiotherapy as part of their breast cancer treatment and the indications for post-mastectomy radiation therapy (PMRT) continue to be extended [23,24]. Radiotherapy harms the cellular structure of fibroblasts and induces collagen and elastic tissue proliferation. This chronic fibrosis impacts the skin and subcutaneous tissue quality and accelerates the loss of the natural breast contour [25]. Ricci et al. reported on 37.5 % capsular contracture (Baker grade III/IV) and 17.5 % reconstructive failure in a meta-analysis of adjuvant radiotherapy applied to tissue expanders or breast implants for breast reconstruction [26]. In a prospective multicenter study in the UK, Potter et al. outlined 9 % reconstructive failure within 3 months of their initial surgery due to serious complications such as implant infection, extrusion or skin necrosis [13]. However, there is a dark figure of breast cancer survivors who are subject to evident but more subtle complaints such as implant rupture, malposition, visibility (animation deformity, rippling), palpability, pain or breast implant illness [27].

In this light, a subset of patients with implant-based breast reconstruction elects to undergo conversion surgery to natural breast reconstruction. In a prospective study, Coriddi et al. surveyed patients who converted from failed implant-based breast reconstruction to microsurgical breast reconstruction [14]. The motivations for conversion surgery were in line with those in our patient collective, including capsular contracture (77 %), cosmetic dissatisfaction (11 %), implant exposure/infection (6 %) or other unclear reasons (6 %). Besides the apparent implant-associated complications on physical health, Mahoney et al. explored and disclosed the disastrous emotional implications of implant failure on the mental health of breast cancer survivors [28]. Coriddi et al. highlighted the substantial impact of conversion surgery on health-related quality of life and outlined a significant increase in patient's satisfaction with breast appearance, psychosocial well-being and physical well-being in the validated BREAST-Q surveys [14].

However, while the authors appreciate that the optimal surgical approach in primary breast reconstruction is elusive up to now [9], patients should be comprehensively counselled on the advantages and complications of implant-based breast reconstruction, particularly when radiotherapy is intended, to protect breast cancer survivors from the experience of reconstructive failure. In this context, in 2022, the International Oncoplastic Breast Consortium for mastectomy and whole breast reconstruction in the setting of post-mastectomy radiation therapy recommended the preference for autologous over implant-based breast reconstruction due to the lower risk of long-term complications [29]. While microsurgical breast reconstruction surpasses the disadvantages of the implant device, the complex procedure is unavoidable associated with the burden of a donor site and unpleasant surgical outcomes as well as reconstructive failure may occur [[30], [31], [32]]. Therefore, patients should be advised on the valid option to forego breast reconstruction. Skillfully performed, aesthetic flat closures can be considered a form of post-mastectomy reconstruction and in the subset of patients who do not desire breast reconstruction high patient satisfaction can be achieved [33].

Implant failure is a major challenge in reconstructive breast surgery and will be in the future, considering the extensive number of implant-based breast reconstructions in the past and its ongoing increase. The indications for conversion surgery to microsurgical breast reconstruction might be categorized in urgent procedures due to major complications, such as implant infection or extrusion, associated with implant loss as well as elective procedures intending a superior aesthetic outcome or patient comfort. Zhao et al. identified radiation therapy and large-volume implants (>500 cc) as risk factors for urgent salvage interventions in a multicenter-study, which included 115 patients who received a conversion to abdominal-based microsurgical breast reconstruction [16]. From a surgical view, conversion surgery to microsurgical breast reconstruction may be more complex due to adverse breast conditions, such as contracture, poor skin quality or even skin necrosis, particularly in urgent salvage reconstruction. Roostaeian et al. compared conversion surgery to primary microsurgical breast reconstruction and reported increased complexity of conversion surgery because of recipient vessel scarring, higher rates of previous radiation therapy and an increased rate of major complications (17.4 percent versus 8.1 percent; p = 0.035) [15]. In this context, plastic surgeons tailor customized concepts and apply staged surgery, alternative tissue sources, and complex microsurgery to meet the patients’ unique preconditions and provide optimal care. This study shows that urgent salvage microsurgical breast reconstruction due to implant infection or extrusion is safe, but associated with significantly more surgical interventions compared to elective conversion, until successful breast reconstruction. To manage the formerly listed complications in patients with urgent salvage reconstruction, we regularly applied negative pressure wound therapy (NPWT) with or without instillation previous to microsurgical breast reconstruction, in order to optimize tissue conditions. The advantages of negative pressure wound therapy in reconstructive and oncologic breast surgery include bacterial decontamination, increased tissue perfusion, and preservation of the skin envelope [34]. Aesthetic considerations are a key element when planning reconstructive interventions. In Europe, the transverse musculocutaneous gracilis (TMG) flap, containing the supple soft tissue and gracilis muscle from the medial thigh, has become a first choice for microsurgical breast reconstruction, similar to the deep inferior epigastric perforator (DIEP)/muscle-sparing – transverse rectus abdominis muscle (MS-TRAM) flap [35,36]. This study shows that the DIEP/MS-TRAM and TMG flap are both reliable for conversion surgery to natural breast reconstruction and have comparable success rates. The TMG flap is particularly valuable, but not exclusive, to breast cancer survivors with low or healthy BMI (<25 kg/m²) [37]. Its nuances and limitations have been published in detail [31,38]. Indeed, the limited soft tissue volume included in the TMG flap, averaging 220–380 g, is typically sufficient for implant substitution in the majority of European patients with failed implant-based breast reconstruction [17,31]. Breast implant sales in Europe show that small implants (100–295 cm³) compose 29.1 %, medium-size implants (300–550 cm³) 67.7 %, and large implants (555–800 cm³) 3.3 % [39]. This is in line with Weichman et al., who evaluated this concern in detail and showed that alternative flaps, such as the TMG flap, provide enough volume to reconstruct a body-appropriate breast size in low-weight or healthy constituted patients (18.5–25 kg/m²) [40,41]. However, in salvage reconstruction, tissue substitution is not limited to the volume but also includes the skin [15]. Mahrhofer et al. examined the skin color match to natural breast skin in secondary breast reconstruction and showed a superior skin color match of the DIEP flap compared to the TMG flap [42].

Failed implant-based breast reconstruction is often associated with unnatural breast dimensions, contour and position on the chest wall. The success of conversion surgery largely depends on the accurate preparation of the breast pocket. Unfortunately, few articles support plastic surgeons with peer-to-peer recommendations for this sophisticated procedure. Below, we summarize key factors for consideration to accomplish an appealing natural breast.

• 1.Marking the natural footprint: In an upright position, the natural footprint should be marked around the deformed breast in precise symmetry to the contralateral breast.
• 2.Scar management: The mastectomy scars in the submammary fold or on the central breast should be re-incised for conversion surgery to avoid additional scars.
• 3.Capsulectomy vs. capsulotomy: The implant capsule and any artificial material should be excised (“capsulectomy”) to reconstruct the natural footprint and release the contracted mastectomy skin. This allows the well perfused tissue to revitalize the mastectomy skin. In very delicate mastectomy skin, circular and vertical incisions through the implant capsule (“capsulotomy”) in short intervals (1 cm) allow the skin to extend substantially, avoiding skin necrosis.
• 4.Pocket preparation: If the implant was placed below the pectoral muscle, the new pocket should be prepared in the anatomic plane above the muscle. The pectoral muscle should be reattached to the thoracic wall. The epipectoral position allows the well-perfused flap tissue to revitalize the mastectomy skin. Pocket preparation should never exceed the medial and lower footprint markings to avoid symmastia and asymmetry or instability of the submammary fold. Care should be taken to release the painful soft tissue scars in the upper outer quadrant of the breast extending into the axilla, which usually appear subsequent to lymph node removal.
• 5.Skin viability: To evaluate skin viability, we strongly recommend the use of Indocyanine green fluorescence angiography (ICGFA) for objective tissue perfusion assessment. ICGFA detected insufficiently perfused skin prone to necrosis and it should be closely excised. In patients with very disproportionate, small breast implants, skin substitution of the lower pole aesthetic unit should be considered to compensate for the lack of breast skin.
• 6.Flap inset: The various options of flap inset of both the DIEP/MS-TRAM and TMG flap have been outlined in the literature [43,44]. To avoid a final lack of skin substitute, the flap skin might be spared by “burying” the flap until mastectomy skin perfusion is secure. To sustain soft tissue volume and smoothen the contour of the breast in the décolleté, the flap should be attached with sutures in both upper quadrants.

This study is limited by its retrospective nature. There could be false or incomplete documentation. However, the review of the medical records was conducted with accuracy. The identified effects might be subject to confounding factors that were not considered. The study analyses two unbalanced groups based on the unbalanced complications of implant-based breast reconstruction in our patient collective. However, the true rate of urgent complications may be higher since a subset of patients may have been treated with other surgical options (aesthetic flat closure, revision implant-based breast reconstruction). Our plastic surgery unit is a renowned referral center for microsurgical breast reconstruction. Our clinical experience with implant-based breast reconstruction might be biased by our expertise in microsurgical breast reconstruction. Nonetheless, this study contributes valuable insights to the limited literature by sharing our clinical experience and surgical pearls, aimed at enhancing the quality of care in microsurgical breast reconstruction.

5. Conclusion

Failure of implant-based breast reconstruction presents a major challenge in reconstructive breast surgery. Microsurgical breast reconstruction is a valuable and safe salvage option that might surpass implant-associated complications and reconstructive failure. While urgent conversion surgery due to major implant-associated complications such as infection or extrusion is safe, it requires more surgical interventions compared to elective conversion surgery. Both the DIEP/MS-TRAM and TMG flaps are reliable options for conversion to microsurgical breast reconstruction.

CRediT authorship contribution statement

Amir Khosrow Bigdeli: Writing – original draft, Conceptualization. Jia Wei Tee: Writing – original draft, Formal analysis, Conceptualization. Felix Hubertus Vollbach: Writing – review & editing, Data curation. Yannick Fabian Diehm: Writing – review & editing, Data curation. Florian Falkner: Writing – review & editing, Data curation. Felix Strübing: Writing – review & editing, Data curation. Maximilian Mahrhofer: Writing – review & editing, Formal analysis. Emre Gazyakan: Writing – review & editing, Formal analysis. Ulrich Kneser: Writing – review & editing, Conceptualization. Laura Cosima Siegwart: Writing – original draft, Supervision, Formal analysis, Conceptualization.

Informed consent

Informed consent was obtained for the personal details and presented images in this study.

Ethics approval

This retrospective study involving human participants was in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The study was approved by the local ethics committee of Rhineland-Palatinate (2024–17877).

Availability of data and material

The data analyzed during the current study are not publicly available due to patient confidentiality but are available from the corresponding author on reasonable request.

Funding

The authors have nothing to disclose. No funding was received for this article.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.