Magnetic resonance lymphangiography in severe primary lymphedema of the right hand

Abstract

Magnetic Resonance Lymphangiography (MRL) enables the assessment of lymphatic morphology without direct lymphatic vessel invasion. We present the case of a 19-year-old male with a two-year history of progressive swelling of the right hand. MRL demonstrated advanced lymphedema (stage 2b) characterized by markedly impaired lymphatic function, extensive fibrotic changes, and hypertrophy of adipose tissue. These findings are consistent with primary lymphedema (lymphedema praecox). Given the severity of the disease, surgical options such as lymphatic-venous anastomosis were deemed unlikely to be beneficial. This case underscores the diagnostic and staging utility of MRL in primary lymphedema and its value in guiding therapeutic decision-making. Primary lymphedema particularly presenting with a unilateral or localized form is considered rare overall, with most reported cases involving broader limb distribution.

Introduction

Lymphedema is a chronic, progressive, and debilitating disorder of the lymphatic circulatory system, characterized by the pathological accumulation of protein-rich interstitial fluid due to impaired drainage capacity. This failure of lymph transport initiates a cascade of inflammatory and fibrotic processes, culminating in the cardinal clinical features of persistent edema, tissue fibrosis, adipose deposition, and recurrent episodes of cellulitis. Etiologically, lymphedema is classified as primary, arising from intrinsic maldevelopment of lymphatic vessels, or secondary, resulting from acquired damage. Primary lymphedema, most frequently manifesting as lymphedema praecox, typically presents during adolescence or early adulthood without an identifiable inciting event, often leading to diagnostic uncertainty and delayed intervention. Accurate staging and therapeutic planning necessitate precise visualization of the lymphatic architecture and its functional dynamics, an area where conventional imaging modalities, such as lymphoscintigraphy, offer limited spatial resolution. In this context, Magnetic Resonance Lymphangiography (MRL) has emerged as a superior, non-invasive imaging technique, providing unparalleled high-resolution, three-dimensional anatomical mapping concurrent with dynamic functional assessment of lymphatic flow. This case report highlights the critical diagnostic utility of MRL in evaluating a complex presentation of severe, isolated primary lymphedema of the right hand, demonstrating its indispensable role in delineating pathological anatomy and guiding subsequent, targeted management strategies.

Case Presentation

A 19-year-old male presented with a two-year history of progressive right-hand swelling. The patient reported no history of trauma, infection, or prior surgeries. Clinical examination revealed non-pitting edema, skin thickening, and decreased range of motion in the right hand (Fig. 1). The secondary causes of lymphedema were excluded.

Fig. 1.

(A and B) showing swelling of right hand.

Past Investigation

Whole body Lymphoscintigraphy:

Agents: Tc-99m sulfur colloid.

Injection Site: Intradermal injection in 1st web space of both hands and feet

Dose: 5 Mbq per site

Timing of image: 15 minutes,30 minutes and 2 hours

Findings: Whole body non-visualization of main lymphatic channels till 2 hours in right hand (Fig. 2).

Fig. 2.

Lymphoscintigraphy images of whole body showing non-visualization of main lymphatic channels till 2 hours.

Doppler USG of both hand vessels: Normal.

CT scan of chest with contrast: Normal. No vascular obstruction or mass lesion.

ICT for filaria: Negative

MR Lymphangiography Findings:

• • Clinical Indication: Right hand swelling for two years.

• • Technique:

•   ○ Contrast Agent: Gadolinium.

•   ○ Injection Site(s): Interdigital web spaces – Intradermal.

•   ○ Injection Volume(s): 1 ml per interdigital space without dilution.

•   ○ No tourniquet was used.

•   ○ Needle size: 31G

•   ○ Local massage: done

•   ○ Timing between injection: very minimum, given consecutively.

• • MRI Scanner Details:

•   ○ Field strength: 3.0 Tesla

•   ○ Vendor: Siemens Healthineers, Germany

•   ○ Coils used: Flex body coil (18 channel)

•   ○ Sequence: 3D T1W FS sequence

Impression

MRL images of the right upper limb show non-visualization of the main lymphatic channels (Fig. 3). There is severe (stage 2b according to international society of lymphology staging [1]) lymphedema of the right hand (Fig. 3), with markedly impaired lymphatic function and minimal to absent lymphatic drainage. Significant fibrotic changes and adipose tissue hypertrophy are also noted in the right hand (Fig. 3). In contrast, the left hand demonstrates normal lymphatic flow (Fig. 4). The venous channels appear intact. No evidence of venous malformation or venous obstruction.

Fig. 3.

A, B, C & D - shows non-visualization of lymphatic channels from the injection site(s) to the regional lymph nodes. (A- After 5 minutes of IV, B- After 10 minutes of IV, C After 30 minutes of IV, D- After 50 minutes of IV).

Fig. 4.

A & B: MRL of left hand shows normal flow in lymphatic channels.

Given the adolescent onset and severity of the disease, primary lymphedema (lymphedema praecox) was the most likely diagnosis.

Differentials include:

Klippel–Trenaunay syndrome: No evidence of limb overgrowth or venous malformation.

Central venous obstruction: The visible venous channels are patent.

Post-infectious lymphatic damage: No evidence of filariasis. ICT for filaria was negative.

The diagnosis of isolated hand lymphedema is particularly challenging, as its presentation can mimic other common conditions such as venous insufficiency, chronic inflammatory arthritis, or soft tissue tumors. Furthermore, severe primary lymphedema, characterized by profound fibrosis and architectural distortion, necessitates advanced imaging for precise anatomical mapping to distinguish it from secondary causes and to guide potential surgical intervention, which relies on identifying specific, patent lymphatic channels.

Management: Due to extensive lymphatic dysfunction, advanced fibrosis and sclerosis of lymphatic vessels surgical interventions such as lymphatic venous anastomosis (LVA) was deemed unlikely to be effective.

Follow up: Only clinical evaluation was done. No change in clinical condition.

Discussion

Lymphedema represents the common outcome of various lymphostatic disorders, though the underlying pathogenesis remains complex. Both lymphatic vessels and nodes undergo structural alterations that correlate closely with impaired function. Hence, accurate localization of affected sites, together with functional assessment of lymph flow, is essential for diagnosis [2,3].

Magnetic Resonance Lymphangiography (MRL) has emerged as a powerful tool in this regard. By exploiting the absorption and transport of contrast agents, MRL provides high-resolution visualization of lymphatic vessels and nodes, delineating abnormalities ranging from small solitary channels to markedly dilated and tortuous trunks [4]. Its mapping capability is comparable to direct lymphangiography with iodized oil, but without the invasiveness. Beyond morphology, contrast-enhanced three-dimensional MRL also detects extralymphatic changes such as edema, fat deposition, and fibrosis, thereby allowing differentiation of lymphedema from other causes of swelling. Importantly, MRL enables real-time and quantitative evaluation of lymph transport, a feature not achievable with traditional techniques like lymphoscintigraphy or direct lymphangiography, which are limited by slow tracer kinetics [4]. Dynamic nodal enhancement patterns and time–signal intensity curve analysis allow assessment of delayed or reduced lymph transport in individual nodes, providing an integrated picture of lymphatic dysfunction.

MRL offers several advantages over conventional methods: superior spatial and temporal resolution, three-dimensional reconstruction, absence of ionizing radiation, and repeatability. It is therefore highly valuable in the diagnosis and differential diagnosis of primary and secondary lymphedema, malignant lymphedema, venous edema, lymphovenous edema, lipedema, and other lymphatic vascular diseases. Limitations include contraindications common to MRI and reduced sensitivity in detecting deep lymphatic structures such as the lumbar trunks, cisterna chyli, and thoracic duct, except in cases of extreme dilatation.

MRL has emerged as an important modality in the assessment of lymphatic disorders, allowing for detailed visualization of lymphatic channels and functional assessment. Unlike lymphoscintigraphy, MRL provides superior spatial resolution and helps in staging lymphedema [5,6].

This case presented with typical MRL findings of advanced primary lymphedema, including absent lymphatic drainage and fibrotic tissue changes [7,8]. The diagnosis should be made early to institute appropriate conservative measures like compression therapy, physiotherapy, and manual lymphatic drainage [9]. Surgical options were not viable given the extent of lymphatic dysfunction in this case, again pointing to timely and individualized management [8,9].

Overall, MRL provides a comprehensive, safe, and reproducible approach for evaluating lymphatic anatomy and function, and plays a pivotal role in both diagnosis and management planning in patients with lymphedema.

Hand lymphedema is notoriously difficult to diagnose, owing both to the complex anatomy of the hand and that early episodes of swelling can be subtle. Small lymphatics and compartments make clinical changes hard to detect, and early classic signs may be missing. It also mimics other conditions such as Rheumatoid arthritis, Cellulitis, or venous disorders hence is often mistakenly diagnosed. Moreover, involvement of the hand alone is uncommon in primary lymphedema (which reduces clinical suspicion).

Advanced imaging to ascertain diagnosis and rule out differential diagnoses for congenital severe primary lymphedema is recommended. Lymphoscintigraphy and Indocyanine green lymphography are techniques to visualize lymphatic flow, identify structural abnormalities, and classify type of disease. Imaging aids in surgical planning, assistance with severity and progression assessment for accurate management.

Conclusion

MRL is an invaluable imaging modality in the diagnosis and staging of primary lymphedema. The case further accentuates its importance in the assessment of lymphatic function, which guides clinical management and provides appropriate expectations for realistic management. Future research is still necessary to find the best possible treatment strategies in severe cases. MRL should be considered early in the patients with atypical or severe manifestations.

Data availability

All relevant data are presented within the manuscript and are available from the corresponding author upon reasonable request.

Declaration of generative AI and AI-assisted technologies in the writing process

During the preparation of this work, the authors used OpenAI’s ChatGPT in order to improve language and readability. After using this tool, the authors reviewed and edited the content as needed and take full responsibility for the content of the publication.

Patient consent

Written informed consent was obtained from the patient for the publication of this case report.